2005-04-16 16:20:36 -06:00
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/*
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* bus.c - bus driver management
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*
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* Copyright (c) 2002-3 Patrick Mochel
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* Copyright (c) 2002-3 Open Source Development Labs
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2007-11-28 16:59:15 -07:00
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* Copyright (c) 2007 Greg Kroah-Hartman <gregkh@suse.de>
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* Copyright (c) 2007 Novell Inc.
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2005-04-16 16:20:36 -06:00
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*
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* This file is released under the GPLv2
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*
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*/
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#include <linux/device.h>
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#include <linux/module.h>
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#include <linux/errno.h>
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include cleanup: Update gfp.h and slab.h includes to prepare for breaking implicit slab.h inclusion from percpu.h
percpu.h is included by sched.h and module.h and thus ends up being
included when building most .c files. percpu.h includes slab.h which
in turn includes gfp.h making everything defined by the two files
universally available and complicating inclusion dependencies.
percpu.h -> slab.h dependency is about to be removed. Prepare for
this change by updating users of gfp and slab facilities include those
headers directly instead of assuming availability. As this conversion
needs to touch large number of source files, the following script is
used as the basis of conversion.
http://userweb.kernel.org/~tj/misc/slabh-sweep.py
The script does the followings.
* Scan files for gfp and slab usages and update includes such that
only the necessary includes are there. ie. if only gfp is used,
gfp.h, if slab is used, slab.h.
* When the script inserts a new include, it looks at the include
blocks and try to put the new include such that its order conforms
to its surrounding. It's put in the include block which contains
core kernel includes, in the same order that the rest are ordered -
alphabetical, Christmas tree, rev-Xmas-tree or at the end if there
doesn't seem to be any matching order.
* If the script can't find a place to put a new include (mostly
because the file doesn't have fitting include block), it prints out
an error message indicating which .h file needs to be added to the
file.
The conversion was done in the following steps.
1. The initial automatic conversion of all .c files updated slightly
over 4000 files, deleting around 700 includes and adding ~480 gfp.h
and ~3000 slab.h inclusions. The script emitted errors for ~400
files.
2. Each error was manually checked. Some didn't need the inclusion,
some needed manual addition while adding it to implementation .h or
embedding .c file was more appropriate for others. This step added
inclusions to around 150 files.
3. The script was run again and the output was compared to the edits
from #2 to make sure no file was left behind.
4. Several build tests were done and a couple of problems were fixed.
e.g. lib/decompress_*.c used malloc/free() wrappers around slab
APIs requiring slab.h to be added manually.
5. The script was run on all .h files but without automatically
editing them as sprinkling gfp.h and slab.h inclusions around .h
files could easily lead to inclusion dependency hell. Most gfp.h
inclusion directives were ignored as stuff from gfp.h was usually
wildly available and often used in preprocessor macros. Each
slab.h inclusion directive was examined and added manually as
necessary.
6. percpu.h was updated not to include slab.h.
7. Build test were done on the following configurations and failures
were fixed. CONFIG_GCOV_KERNEL was turned off for all tests (as my
distributed build env didn't work with gcov compiles) and a few
more options had to be turned off depending on archs to make things
build (like ipr on powerpc/64 which failed due to missing writeq).
* x86 and x86_64 UP and SMP allmodconfig and a custom test config.
* powerpc and powerpc64 SMP allmodconfig
* sparc and sparc64 SMP allmodconfig
* ia64 SMP allmodconfig
* s390 SMP allmodconfig
* alpha SMP allmodconfig
* um on x86_64 SMP allmodconfig
8. percpu.h modifications were reverted so that it could be applied as
a separate patch and serve as bisection point.
Given the fact that I had only a couple of failures from tests on step
6, I'm fairly confident about the coverage of this conversion patch.
If there is a breakage, it's likely to be something in one of the arch
headers which should be easily discoverable easily on most builds of
the specific arch.
Signed-off-by: Tejun Heo <tj@kernel.org>
Guess-its-ok-by: Christoph Lameter <cl@linux-foundation.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Lee Schermerhorn <Lee.Schermerhorn@hp.com>
2010-03-24 02:04:11 -06:00
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#include <linux/slab.h>
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2005-04-16 16:20:36 -06:00
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#include <linux/init.h>
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#include <linux/string.h>
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2011-12-14 15:29:38 -07:00
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#include <linux/mutex.h>
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2013-08-27 11:24:15 -06:00
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#include <linux/sysfs.h>
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2005-04-16 16:20:36 -06:00
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#include "base.h"
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#include "power/power.h"
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2011-12-14 15:29:38 -07:00
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/* /sys/devices/system */
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2012-04-16 19:14:10 -06:00
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static struct kset *system_kset;
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2011-12-14 15:29:38 -07:00
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2005-04-16 16:20:36 -06:00
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#define to_bus_attr(_attr) container_of(_attr, struct bus_attribute, attr)
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/*
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* sysfs bindings for drivers
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*/
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#define to_drv_attr(_attr) container_of(_attr, struct driver_attribute, attr)
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Driver core: udev triggered device-<>driver binding
We get two per-bus sysfs files:
ls-l /sys/subsystem/usb
drwxr-xr-x 2 root root 0 2007-02-16 16:42 devices
drwxr-xr-x 7 root root 0 2007-02-16 14:55 drivers
-rw-r--r-- 1 root root 4096 2007-02-16 16:42 drivers_autoprobe
--w------- 1 root root 4096 2007-02-16 16:42 drivers_probe
The flag "drivers_autoprobe" controls the behavior of the bus to bind
devices by default, or just initialize the device and leave it alone.
The command "drivers_probe" accepts a bus_id and the bus tries to bind a
driver to this device.
Systems who want to control the driver binding with udev, switch off the
bus initiated probing:
echo 0 > /sys/subsystem/usb/drivers_autoprobe
echo 0 > /sys/subsystem/pcmcia/drivers_autoprobe
...
and initiate the probing with udev rules like:
ACTION=="add", SUBSYSTEM=="usb", ATTR{subsystem/drivers_probe}="$kernel"
ACTION=="add", SUBSYSTEM=="pcmcia", ATTR{subsystem/drivers_probe}="$kernel"
...
Custom driver binding can happen in earlier rules by something like:
ACTION=="add", SUBSYSTEM=="usb", \
ATTRS{idVendor}=="1234", ATTRS{idProduct}=="5678" \
ATTR{subsystem/drivers/<custom-driver>/bind}="$kernel"
This is intended to solve the modprobe.conf mess with "install-rules", custom
bind/unbind-scripts and all the weird things people invented over the years.
It should also provide the functionality "libusual" was supposed to do.
With udev, one can just write a udev rule to drive all USB-disks at the
third port of USB-hub by the "ub" driver, and everything else by
usb-storage. One can also instruct udev to bind different wireless
drivers to identical cards - just selected by the pcmcia slot-number, and
whatever ...
To use the mentioned rules, it needs udev version 106, to be able to
write ATTR{}="$kernel" to sysfs files.
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2007-02-16 09:33:36 -07:00
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static int __must_check bus_rescan_devices_helper(struct device *dev,
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void *data);
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2007-09-13 03:53:13 -06:00
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static struct bus_type *bus_get(struct bus_type *bus)
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{
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2007-11-01 20:41:16 -06:00
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if (bus) {
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kset_get(&bus->p->subsys);
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return bus;
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}
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return NULL;
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2007-09-13 03:53:13 -06:00
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}
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2007-09-13 03:53:13 -06:00
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static void bus_put(struct bus_type *bus)
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{
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2007-11-01 20:41:16 -06:00
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if (bus)
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kset_put(&bus->p->subsys);
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2007-09-13 03:53:13 -06:00
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}
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2008-01-24 23:50:12 -07:00
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static ssize_t drv_attr_show(struct kobject *kobj, struct attribute *attr,
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char *buf)
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2005-04-16 16:20:36 -06:00
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{
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2008-01-24 23:50:12 -07:00
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struct driver_attribute *drv_attr = to_drv_attr(attr);
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2007-11-28 16:59:15 -07:00
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struct driver_private *drv_priv = to_driver(kobj);
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2005-04-29 00:23:47 -06:00
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ssize_t ret = -EIO;
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2005-04-16 16:20:36 -06:00
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if (drv_attr->show)
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2007-11-28 16:59:15 -07:00
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ret = drv_attr->show(drv_priv->driver, buf);
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2005-04-16 16:20:36 -06:00
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return ret;
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}
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2008-01-24 23:50:12 -07:00
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static ssize_t drv_attr_store(struct kobject *kobj, struct attribute *attr,
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const char *buf, size_t count)
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2005-04-16 16:20:36 -06:00
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{
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2008-01-24 23:50:12 -07:00
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struct driver_attribute *drv_attr = to_drv_attr(attr);
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2007-11-28 16:59:15 -07:00
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struct driver_private *drv_priv = to_driver(kobj);
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2005-04-29 00:23:47 -06:00
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ssize_t ret = -EIO;
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2005-04-16 16:20:36 -06:00
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if (drv_attr->store)
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2007-11-28 16:59:15 -07:00
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ret = drv_attr->store(drv_priv->driver, buf, count);
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2005-04-16 16:20:36 -06:00
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return ret;
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}
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|
2010-01-18 18:58:23 -07:00
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static const struct sysfs_ops driver_sysfs_ops = {
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2005-04-16 16:20:36 -06:00
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.show = drv_attr_show,
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.store = drv_attr_store,
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};
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2007-11-28 16:59:15 -07:00
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static void driver_release(struct kobject *kobj)
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2005-04-16 16:20:36 -06:00
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{
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2007-11-28 16:59:15 -07:00
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struct driver_private *drv_priv = to_driver(kobj);
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2008-03-04 17:41:05 -07:00
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pr_debug("driver: '%s': %s\n", kobject_name(kobj), __func__);
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2007-11-28 16:59:15 -07:00
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kfree(drv_priv);
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2005-04-16 16:20:36 -06:00
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}
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2007-10-11 10:47:49 -06:00
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static struct kobj_type driver_ktype = {
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2005-04-16 16:20:36 -06:00
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.sysfs_ops = &driver_sysfs_ops,
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.release = driver_release,
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};
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/*
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* sysfs bindings for buses
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*/
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2008-01-24 23:50:12 -07:00
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static ssize_t bus_attr_show(struct kobject *kobj, struct attribute *attr,
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char *buf)
|
2005-04-16 16:20:36 -06:00
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{
|
2008-01-24 23:50:12 -07:00
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struct bus_attribute *bus_attr = to_bus_attr(attr);
|
2010-11-15 15:13:18 -07:00
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struct subsys_private *subsys_priv = to_subsys_private(kobj);
|
2005-04-16 16:20:36 -06:00
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ssize_t ret = 0;
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if (bus_attr->show)
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2010-11-15 15:13:18 -07:00
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ret = bus_attr->show(subsys_priv->bus, buf);
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2005-04-16 16:20:36 -06:00
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return ret;
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}
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2008-01-24 23:50:12 -07:00
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static ssize_t bus_attr_store(struct kobject *kobj, struct attribute *attr,
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const char *buf, size_t count)
|
2005-04-16 16:20:36 -06:00
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{
|
2008-01-24 23:50:12 -07:00
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struct bus_attribute *bus_attr = to_bus_attr(attr);
|
2010-11-15 15:13:18 -07:00
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struct subsys_private *subsys_priv = to_subsys_private(kobj);
|
2005-04-16 16:20:36 -06:00
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ssize_t ret = 0;
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if (bus_attr->store)
|
2010-11-15 15:13:18 -07:00
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ret = bus_attr->store(subsys_priv->bus, buf, count);
|
2005-04-16 16:20:36 -06:00
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return ret;
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}
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|
2010-01-18 18:58:23 -07:00
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static const struct sysfs_ops bus_sysfs_ops = {
|
2005-04-16 16:20:36 -06:00
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.show = bus_attr_show,
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.store = bus_attr_store,
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};
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2008-01-24 23:50:12 -07:00
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int bus_create_file(struct bus_type *bus, struct bus_attribute *attr)
|
2005-04-16 16:20:36 -06:00
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{
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int error;
|
2007-09-13 03:53:13 -06:00
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if (bus_get(bus)) {
|
2007-11-01 20:41:16 -06:00
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error = sysfs_create_file(&bus->p->subsys.kobj, &attr->attr);
|
2007-09-13 03:53:13 -06:00
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bus_put(bus);
|
2005-04-16 16:20:36 -06:00
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} else
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error = -EINVAL;
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return error;
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|
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}
|
2008-01-24 23:50:12 -07:00
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EXPORT_SYMBOL_GPL(bus_create_file);
|
2005-04-16 16:20:36 -06:00
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2008-01-24 23:50:12 -07:00
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void bus_remove_file(struct bus_type *bus, struct bus_attribute *attr)
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2005-04-16 16:20:36 -06:00
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{
|
2007-09-13 03:53:13 -06:00
|
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if (bus_get(bus)) {
|
2007-11-01 20:41:16 -06:00
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sysfs_remove_file(&bus->p->subsys.kobj, &attr->attr);
|
2007-09-13 03:53:13 -06:00
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bus_put(bus);
|
2005-04-16 16:20:36 -06:00
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}
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}
|
2008-01-24 23:50:12 -07:00
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EXPORT_SYMBOL_GPL(bus_remove_file);
|
2005-04-16 16:20:36 -06:00
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|
2014-01-04 06:21:42 -07:00
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static void bus_release(struct kobject *kobj)
|
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|
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{
|
|
|
|
struct subsys_private *priv =
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container_of(kobj, typeof(*priv), subsys.kobj);
|
|
|
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struct bus_type *bus = priv->bus;
|
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kfree(priv);
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bus->p = NULL;
|
|
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}
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|
2007-05-26 03:21:36 -06:00
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static struct kobj_type bus_ktype = {
|
2005-04-16 16:20:36 -06:00
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.sysfs_ops = &bus_sysfs_ops,
|
2014-01-04 06:21:42 -07:00
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.release = bus_release,
|
2007-05-26 03:21:36 -06:00
|
|
|
};
|
|
|
|
|
|
|
|
static int bus_uevent_filter(struct kset *kset, struct kobject *kobj)
|
|
|
|
{
|
|
|
|
struct kobj_type *ktype = get_ktype(kobj);
|
|
|
|
|
|
|
|
if (ktype == &bus_ktype)
|
|
|
|
return 1;
|
|
|
|
return 0;
|
|
|
|
}
|
2005-04-16 16:20:36 -06:00
|
|
|
|
2009-12-31 06:52:51 -07:00
|
|
|
static const struct kset_uevent_ops bus_uevent_ops = {
|
2007-05-26 03:21:36 -06:00
|
|
|
.filter = bus_uevent_filter,
|
2005-04-16 16:20:36 -06:00
|
|
|
};
|
|
|
|
|
2007-10-29 22:22:26 -06:00
|
|
|
static struct kset *bus_kset;
|
2005-04-16 16:20:36 -06:00
|
|
|
|
2005-11-23 16:43:50 -07:00
|
|
|
/* Manually detach a device from its associated driver. */
|
2013-08-23 16:04:42 -06:00
|
|
|
static ssize_t unbind_store(struct device_driver *drv, const char *buf,
|
|
|
|
size_t count)
|
2005-06-22 17:09:05 -06:00
|
|
|
{
|
2007-09-13 03:53:13 -06:00
|
|
|
struct bus_type *bus = bus_get(drv->bus);
|
2005-06-22 17:09:05 -06:00
|
|
|
struct device *dev;
|
|
|
|
int err = -ENODEV;
|
|
|
|
|
2008-01-27 11:29:20 -07:00
|
|
|
dev = bus_find_device_by_name(bus, NULL, buf);
|
2005-11-23 16:43:50 -07:00
|
|
|
if (dev && dev->driver == drv) {
|
[PATCH] Hold the device's parent's lock during probe and remove
This patch (as604) makes the driver core hold a device's parent's lock
as well as the device's lock during calls to the probe and remove
methods in a driver. This facility is needed by USB device drivers,
owing to the peculiar way USB devices work:
A device provides multiple interfaces, and drivers are bound
to interfaces rather than to devices;
Nevertheless a reset, reset-configuration, suspend, or resume
affects the entire device and requires the caller to hold the
lock for the device, not just a lock for one of the interfaces.
Since a USB driver's probe method is always called with the interface
lock held, the locking order rules (always lock parent before child)
prevent these methods from acquiring the device lock. The solution
provided here is to call all probe and remove methods, for all devices
(not just USB), with the parent lock already acquired.
Although currently only the USB subsystem requires these changes, people
have mentioned in prior discussion that the overhead of acquiring an
extra semaphore in all the prove/remove sequences is not overly large.
Up to now, the USB core has been using its own set of private
semaphores. A followup patch will remove them, relying entirely on the
device semaphores provided by the driver core.
The code paths affected by this patch are:
device_add and device_del: The USB core already holds the parent
lock, so no actual change is needed.
driver_register and driver_unregister: The driver core will now
lock both the parent and the device before probing or removing.
driver_bind and driver_unbind (in sysfs): These routines will
now lock both the parent and the device before binding or
unbinding.
bus_rescan_devices: The helper routine will lock the parent
before probing a device.
I have not tested this patch for conflicts with other subsystems. As
far as I can see, the only possibility of conflict would lie in the
bus_rescan_devices pathway, and it seems pretty remote. Nevertheless,
it would be good for this to get a lot of testing in -mm.
Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2005-11-17 14:54:12 -07:00
|
|
|
if (dev->parent) /* Needed for USB */
|
2010-02-17 11:57:05 -07:00
|
|
|
device_lock(dev->parent);
|
2005-06-22 17:09:05 -06:00
|
|
|
device_release_driver(dev);
|
[PATCH] Hold the device's parent's lock during probe and remove
This patch (as604) makes the driver core hold a device's parent's lock
as well as the device's lock during calls to the probe and remove
methods in a driver. This facility is needed by USB device drivers,
owing to the peculiar way USB devices work:
A device provides multiple interfaces, and drivers are bound
to interfaces rather than to devices;
Nevertheless a reset, reset-configuration, suspend, or resume
affects the entire device and requires the caller to hold the
lock for the device, not just a lock for one of the interfaces.
Since a USB driver's probe method is always called with the interface
lock held, the locking order rules (always lock parent before child)
prevent these methods from acquiring the device lock. The solution
provided here is to call all probe and remove methods, for all devices
(not just USB), with the parent lock already acquired.
Although currently only the USB subsystem requires these changes, people
have mentioned in prior discussion that the overhead of acquiring an
extra semaphore in all the prove/remove sequences is not overly large.
Up to now, the USB core has been using its own set of private
semaphores. A followup patch will remove them, relying entirely on the
device semaphores provided by the driver core.
The code paths affected by this patch are:
device_add and device_del: The USB core already holds the parent
lock, so no actual change is needed.
driver_register and driver_unregister: The driver core will now
lock both the parent and the device before probing or removing.
driver_bind and driver_unbind (in sysfs): These routines will
now lock both the parent and the device before binding or
unbinding.
bus_rescan_devices: The helper routine will lock the parent
before probing a device.
I have not tested this patch for conflicts with other subsystems. As
far as I can see, the only possibility of conflict would lie in the
bus_rescan_devices pathway, and it seems pretty remote. Nevertheless,
it would be good for this to get a lot of testing in -mm.
Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2005-11-17 14:54:12 -07:00
|
|
|
if (dev->parent)
|
2010-02-17 11:57:05 -07:00
|
|
|
device_unlock(dev->parent);
|
2005-06-22 17:09:05 -06:00
|
|
|
err = count;
|
|
|
|
}
|
2005-11-23 16:43:50 -07:00
|
|
|
put_device(dev);
|
2007-09-13 03:53:13 -06:00
|
|
|
bus_put(bus);
|
2005-11-23 16:43:50 -07:00
|
|
|
return err;
|
2005-06-22 17:09:05 -06:00
|
|
|
}
|
2013-08-23 16:04:42 -06:00
|
|
|
static DRIVER_ATTR_WO(unbind);
|
2005-06-22 17:09:05 -06:00
|
|
|
|
2005-06-22 17:09:05 -06:00
|
|
|
/*
|
|
|
|
* Manually attach a device to a driver.
|
|
|
|
* Note: the driver must want to bind to the device,
|
|
|
|
* it is not possible to override the driver's id table.
|
|
|
|
*/
|
2013-08-23 16:04:42 -06:00
|
|
|
static ssize_t bind_store(struct device_driver *drv, const char *buf,
|
|
|
|
size_t count)
|
2005-06-22 17:09:05 -06:00
|
|
|
{
|
2007-09-13 03:53:13 -06:00
|
|
|
struct bus_type *bus = bus_get(drv->bus);
|
2005-06-22 17:09:05 -06:00
|
|
|
struct device *dev;
|
|
|
|
int err = -ENODEV;
|
|
|
|
|
2008-01-27 11:29:20 -07:00
|
|
|
dev = bus_find_device_by_name(bus, NULL, buf);
|
2009-01-21 08:27:47 -07:00
|
|
|
if (dev && dev->driver == NULL && driver_match_device(drv, dev)) {
|
[PATCH] Hold the device's parent's lock during probe and remove
This patch (as604) makes the driver core hold a device's parent's lock
as well as the device's lock during calls to the probe and remove
methods in a driver. This facility is needed by USB device drivers,
owing to the peculiar way USB devices work:
A device provides multiple interfaces, and drivers are bound
to interfaces rather than to devices;
Nevertheless a reset, reset-configuration, suspend, or resume
affects the entire device and requires the caller to hold the
lock for the device, not just a lock for one of the interfaces.
Since a USB driver's probe method is always called with the interface
lock held, the locking order rules (always lock parent before child)
prevent these methods from acquiring the device lock. The solution
provided here is to call all probe and remove methods, for all devices
(not just USB), with the parent lock already acquired.
Although currently only the USB subsystem requires these changes, people
have mentioned in prior discussion that the overhead of acquiring an
extra semaphore in all the prove/remove sequences is not overly large.
Up to now, the USB core has been using its own set of private
semaphores. A followup patch will remove them, relying entirely on the
device semaphores provided by the driver core.
The code paths affected by this patch are:
device_add and device_del: The USB core already holds the parent
lock, so no actual change is needed.
driver_register and driver_unregister: The driver core will now
lock both the parent and the device before probing or removing.
driver_bind and driver_unbind (in sysfs): These routines will
now lock both the parent and the device before binding or
unbinding.
bus_rescan_devices: The helper routine will lock the parent
before probing a device.
I have not tested this patch for conflicts with other subsystems. As
far as I can see, the only possibility of conflict would lie in the
bus_rescan_devices pathway, and it seems pretty remote. Nevertheless,
it would be good for this to get a lot of testing in -mm.
Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2005-11-17 14:54:12 -07:00
|
|
|
if (dev->parent) /* Needed for USB */
|
2010-02-17 11:57:05 -07:00
|
|
|
device_lock(dev->parent);
|
|
|
|
device_lock(dev);
|
2005-06-22 17:09:05 -06:00
|
|
|
err = driver_probe_device(drv, dev);
|
2010-02-17 11:57:05 -07:00
|
|
|
device_unlock(dev);
|
[PATCH] Hold the device's parent's lock during probe and remove
This patch (as604) makes the driver core hold a device's parent's lock
as well as the device's lock during calls to the probe and remove
methods in a driver. This facility is needed by USB device drivers,
owing to the peculiar way USB devices work:
A device provides multiple interfaces, and drivers are bound
to interfaces rather than to devices;
Nevertheless a reset, reset-configuration, suspend, or resume
affects the entire device and requires the caller to hold the
lock for the device, not just a lock for one of the interfaces.
Since a USB driver's probe method is always called with the interface
lock held, the locking order rules (always lock parent before child)
prevent these methods from acquiring the device lock. The solution
provided here is to call all probe and remove methods, for all devices
(not just USB), with the parent lock already acquired.
Although currently only the USB subsystem requires these changes, people
have mentioned in prior discussion that the overhead of acquiring an
extra semaphore in all the prove/remove sequences is not overly large.
Up to now, the USB core has been using its own set of private
semaphores. A followup patch will remove them, relying entirely on the
device semaphores provided by the driver core.
The code paths affected by this patch are:
device_add and device_del: The USB core already holds the parent
lock, so no actual change is needed.
driver_register and driver_unregister: The driver core will now
lock both the parent and the device before probing or removing.
driver_bind and driver_unbind (in sysfs): These routines will
now lock both the parent and the device before binding or
unbinding.
bus_rescan_devices: The helper routine will lock the parent
before probing a device.
I have not tested this patch for conflicts with other subsystems. As
far as I can see, the only possibility of conflict would lie in the
bus_rescan_devices pathway, and it seems pretty remote. Nevertheless,
it would be good for this to get a lot of testing in -mm.
Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2005-11-17 14:54:12 -07:00
|
|
|
if (dev->parent)
|
2010-02-17 11:57:05 -07:00
|
|
|
device_unlock(dev->parent);
|
2006-03-22 14:26:25 -07:00
|
|
|
|
2008-01-24 23:50:12 -07:00
|
|
|
if (err > 0) {
|
|
|
|
/* success */
|
2006-03-22 14:26:25 -07:00
|
|
|
err = count;
|
2008-01-24 23:50:12 -07:00
|
|
|
} else if (err == 0) {
|
|
|
|
/* driver didn't accept device */
|
2006-03-22 14:26:25 -07:00
|
|
|
err = -ENODEV;
|
2008-01-24 23:50:12 -07:00
|
|
|
}
|
2005-06-22 17:09:05 -06:00
|
|
|
}
|
2005-11-23 16:43:50 -07:00
|
|
|
put_device(dev);
|
2007-09-13 03:53:13 -06:00
|
|
|
bus_put(bus);
|
2005-11-23 16:43:50 -07:00
|
|
|
return err;
|
2005-06-22 17:09:05 -06:00
|
|
|
}
|
2013-08-23 16:04:42 -06:00
|
|
|
static DRIVER_ATTR_WO(bind);
|
2005-06-22 17:09:05 -06:00
|
|
|
|
Driver core: udev triggered device-<>driver binding
We get two per-bus sysfs files:
ls-l /sys/subsystem/usb
drwxr-xr-x 2 root root 0 2007-02-16 16:42 devices
drwxr-xr-x 7 root root 0 2007-02-16 14:55 drivers
-rw-r--r-- 1 root root 4096 2007-02-16 16:42 drivers_autoprobe
--w------- 1 root root 4096 2007-02-16 16:42 drivers_probe
The flag "drivers_autoprobe" controls the behavior of the bus to bind
devices by default, or just initialize the device and leave it alone.
The command "drivers_probe" accepts a bus_id and the bus tries to bind a
driver to this device.
Systems who want to control the driver binding with udev, switch off the
bus initiated probing:
echo 0 > /sys/subsystem/usb/drivers_autoprobe
echo 0 > /sys/subsystem/pcmcia/drivers_autoprobe
...
and initiate the probing with udev rules like:
ACTION=="add", SUBSYSTEM=="usb", ATTR{subsystem/drivers_probe}="$kernel"
ACTION=="add", SUBSYSTEM=="pcmcia", ATTR{subsystem/drivers_probe}="$kernel"
...
Custom driver binding can happen in earlier rules by something like:
ACTION=="add", SUBSYSTEM=="usb", \
ATTRS{idVendor}=="1234", ATTRS{idProduct}=="5678" \
ATTR{subsystem/drivers/<custom-driver>/bind}="$kernel"
This is intended to solve the modprobe.conf mess with "install-rules", custom
bind/unbind-scripts and all the weird things people invented over the years.
It should also provide the functionality "libusual" was supposed to do.
With udev, one can just write a udev rule to drive all USB-disks at the
third port of USB-hub by the "ub" driver, and everything else by
usb-storage. One can also instruct udev to bind different wireless
drivers to identical cards - just selected by the pcmcia slot-number, and
whatever ...
To use the mentioned rules, it needs udev version 106, to be able to
write ATTR{}="$kernel" to sysfs files.
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2007-02-16 09:33:36 -07:00
|
|
|
static ssize_t show_drivers_autoprobe(struct bus_type *bus, char *buf)
|
|
|
|
{
|
2007-11-01 20:41:16 -06:00
|
|
|
return sprintf(buf, "%d\n", bus->p->drivers_autoprobe);
|
Driver core: udev triggered device-<>driver binding
We get two per-bus sysfs files:
ls-l /sys/subsystem/usb
drwxr-xr-x 2 root root 0 2007-02-16 16:42 devices
drwxr-xr-x 7 root root 0 2007-02-16 14:55 drivers
-rw-r--r-- 1 root root 4096 2007-02-16 16:42 drivers_autoprobe
--w------- 1 root root 4096 2007-02-16 16:42 drivers_probe
The flag "drivers_autoprobe" controls the behavior of the bus to bind
devices by default, or just initialize the device and leave it alone.
The command "drivers_probe" accepts a bus_id and the bus tries to bind a
driver to this device.
Systems who want to control the driver binding with udev, switch off the
bus initiated probing:
echo 0 > /sys/subsystem/usb/drivers_autoprobe
echo 0 > /sys/subsystem/pcmcia/drivers_autoprobe
...
and initiate the probing with udev rules like:
ACTION=="add", SUBSYSTEM=="usb", ATTR{subsystem/drivers_probe}="$kernel"
ACTION=="add", SUBSYSTEM=="pcmcia", ATTR{subsystem/drivers_probe}="$kernel"
...
Custom driver binding can happen in earlier rules by something like:
ACTION=="add", SUBSYSTEM=="usb", \
ATTRS{idVendor}=="1234", ATTRS{idProduct}=="5678" \
ATTR{subsystem/drivers/<custom-driver>/bind}="$kernel"
This is intended to solve the modprobe.conf mess with "install-rules", custom
bind/unbind-scripts and all the weird things people invented over the years.
It should also provide the functionality "libusual" was supposed to do.
With udev, one can just write a udev rule to drive all USB-disks at the
third port of USB-hub by the "ub" driver, and everything else by
usb-storage. One can also instruct udev to bind different wireless
drivers to identical cards - just selected by the pcmcia slot-number, and
whatever ...
To use the mentioned rules, it needs udev version 106, to be able to
write ATTR{}="$kernel" to sysfs files.
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2007-02-16 09:33:36 -07:00
|
|
|
}
|
|
|
|
|
|
|
|
static ssize_t store_drivers_autoprobe(struct bus_type *bus,
|
|
|
|
const char *buf, size_t count)
|
|
|
|
{
|
|
|
|
if (buf[0] == '0')
|
2007-11-01 20:41:16 -06:00
|
|
|
bus->p->drivers_autoprobe = 0;
|
Driver core: udev triggered device-<>driver binding
We get two per-bus sysfs files:
ls-l /sys/subsystem/usb
drwxr-xr-x 2 root root 0 2007-02-16 16:42 devices
drwxr-xr-x 7 root root 0 2007-02-16 14:55 drivers
-rw-r--r-- 1 root root 4096 2007-02-16 16:42 drivers_autoprobe
--w------- 1 root root 4096 2007-02-16 16:42 drivers_probe
The flag "drivers_autoprobe" controls the behavior of the bus to bind
devices by default, or just initialize the device and leave it alone.
The command "drivers_probe" accepts a bus_id and the bus tries to bind a
driver to this device.
Systems who want to control the driver binding with udev, switch off the
bus initiated probing:
echo 0 > /sys/subsystem/usb/drivers_autoprobe
echo 0 > /sys/subsystem/pcmcia/drivers_autoprobe
...
and initiate the probing with udev rules like:
ACTION=="add", SUBSYSTEM=="usb", ATTR{subsystem/drivers_probe}="$kernel"
ACTION=="add", SUBSYSTEM=="pcmcia", ATTR{subsystem/drivers_probe}="$kernel"
...
Custom driver binding can happen in earlier rules by something like:
ACTION=="add", SUBSYSTEM=="usb", \
ATTRS{idVendor}=="1234", ATTRS{idProduct}=="5678" \
ATTR{subsystem/drivers/<custom-driver>/bind}="$kernel"
This is intended to solve the modprobe.conf mess with "install-rules", custom
bind/unbind-scripts and all the weird things people invented over the years.
It should also provide the functionality "libusual" was supposed to do.
With udev, one can just write a udev rule to drive all USB-disks at the
third port of USB-hub by the "ub" driver, and everything else by
usb-storage. One can also instruct udev to bind different wireless
drivers to identical cards - just selected by the pcmcia slot-number, and
whatever ...
To use the mentioned rules, it needs udev version 106, to be able to
write ATTR{}="$kernel" to sysfs files.
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2007-02-16 09:33:36 -07:00
|
|
|
else
|
2007-11-01 20:41:16 -06:00
|
|
|
bus->p->drivers_autoprobe = 1;
|
Driver core: udev triggered device-<>driver binding
We get two per-bus sysfs files:
ls-l /sys/subsystem/usb
drwxr-xr-x 2 root root 0 2007-02-16 16:42 devices
drwxr-xr-x 7 root root 0 2007-02-16 14:55 drivers
-rw-r--r-- 1 root root 4096 2007-02-16 16:42 drivers_autoprobe
--w------- 1 root root 4096 2007-02-16 16:42 drivers_probe
The flag "drivers_autoprobe" controls the behavior of the bus to bind
devices by default, or just initialize the device and leave it alone.
The command "drivers_probe" accepts a bus_id and the bus tries to bind a
driver to this device.
Systems who want to control the driver binding with udev, switch off the
bus initiated probing:
echo 0 > /sys/subsystem/usb/drivers_autoprobe
echo 0 > /sys/subsystem/pcmcia/drivers_autoprobe
...
and initiate the probing with udev rules like:
ACTION=="add", SUBSYSTEM=="usb", ATTR{subsystem/drivers_probe}="$kernel"
ACTION=="add", SUBSYSTEM=="pcmcia", ATTR{subsystem/drivers_probe}="$kernel"
...
Custom driver binding can happen in earlier rules by something like:
ACTION=="add", SUBSYSTEM=="usb", \
ATTRS{idVendor}=="1234", ATTRS{idProduct}=="5678" \
ATTR{subsystem/drivers/<custom-driver>/bind}="$kernel"
This is intended to solve the modprobe.conf mess with "install-rules", custom
bind/unbind-scripts and all the weird things people invented over the years.
It should also provide the functionality "libusual" was supposed to do.
With udev, one can just write a udev rule to drive all USB-disks at the
third port of USB-hub by the "ub" driver, and everything else by
usb-storage. One can also instruct udev to bind different wireless
drivers to identical cards - just selected by the pcmcia slot-number, and
whatever ...
To use the mentioned rules, it needs udev version 106, to be able to
write ATTR{}="$kernel" to sysfs files.
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2007-02-16 09:33:36 -07:00
|
|
|
return count;
|
|
|
|
}
|
|
|
|
|
|
|
|
static ssize_t store_drivers_probe(struct bus_type *bus,
|
|
|
|
const char *buf, size_t count)
|
|
|
|
{
|
|
|
|
struct device *dev;
|
2014-10-31 11:13:07 -06:00
|
|
|
int err = -EINVAL;
|
Driver core: udev triggered device-<>driver binding
We get two per-bus sysfs files:
ls-l /sys/subsystem/usb
drwxr-xr-x 2 root root 0 2007-02-16 16:42 devices
drwxr-xr-x 7 root root 0 2007-02-16 14:55 drivers
-rw-r--r-- 1 root root 4096 2007-02-16 16:42 drivers_autoprobe
--w------- 1 root root 4096 2007-02-16 16:42 drivers_probe
The flag "drivers_autoprobe" controls the behavior of the bus to bind
devices by default, or just initialize the device and leave it alone.
The command "drivers_probe" accepts a bus_id and the bus tries to bind a
driver to this device.
Systems who want to control the driver binding with udev, switch off the
bus initiated probing:
echo 0 > /sys/subsystem/usb/drivers_autoprobe
echo 0 > /sys/subsystem/pcmcia/drivers_autoprobe
...
and initiate the probing with udev rules like:
ACTION=="add", SUBSYSTEM=="usb", ATTR{subsystem/drivers_probe}="$kernel"
ACTION=="add", SUBSYSTEM=="pcmcia", ATTR{subsystem/drivers_probe}="$kernel"
...
Custom driver binding can happen in earlier rules by something like:
ACTION=="add", SUBSYSTEM=="usb", \
ATTRS{idVendor}=="1234", ATTRS{idProduct}=="5678" \
ATTR{subsystem/drivers/<custom-driver>/bind}="$kernel"
This is intended to solve the modprobe.conf mess with "install-rules", custom
bind/unbind-scripts and all the weird things people invented over the years.
It should also provide the functionality "libusual" was supposed to do.
With udev, one can just write a udev rule to drive all USB-disks at the
third port of USB-hub by the "ub" driver, and everything else by
usb-storage. One can also instruct udev to bind different wireless
drivers to identical cards - just selected by the pcmcia slot-number, and
whatever ...
To use the mentioned rules, it needs udev version 106, to be able to
write ATTR{}="$kernel" to sysfs files.
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2007-02-16 09:33:36 -07:00
|
|
|
|
2008-01-27 11:29:20 -07:00
|
|
|
dev = bus_find_device_by_name(bus, NULL, buf);
|
Driver core: udev triggered device-<>driver binding
We get two per-bus sysfs files:
ls-l /sys/subsystem/usb
drwxr-xr-x 2 root root 0 2007-02-16 16:42 devices
drwxr-xr-x 7 root root 0 2007-02-16 14:55 drivers
-rw-r--r-- 1 root root 4096 2007-02-16 16:42 drivers_autoprobe
--w------- 1 root root 4096 2007-02-16 16:42 drivers_probe
The flag "drivers_autoprobe" controls the behavior of the bus to bind
devices by default, or just initialize the device and leave it alone.
The command "drivers_probe" accepts a bus_id and the bus tries to bind a
driver to this device.
Systems who want to control the driver binding with udev, switch off the
bus initiated probing:
echo 0 > /sys/subsystem/usb/drivers_autoprobe
echo 0 > /sys/subsystem/pcmcia/drivers_autoprobe
...
and initiate the probing with udev rules like:
ACTION=="add", SUBSYSTEM=="usb", ATTR{subsystem/drivers_probe}="$kernel"
ACTION=="add", SUBSYSTEM=="pcmcia", ATTR{subsystem/drivers_probe}="$kernel"
...
Custom driver binding can happen in earlier rules by something like:
ACTION=="add", SUBSYSTEM=="usb", \
ATTRS{idVendor}=="1234", ATTRS{idProduct}=="5678" \
ATTR{subsystem/drivers/<custom-driver>/bind}="$kernel"
This is intended to solve the modprobe.conf mess with "install-rules", custom
bind/unbind-scripts and all the weird things people invented over the years.
It should also provide the functionality "libusual" was supposed to do.
With udev, one can just write a udev rule to drive all USB-disks at the
third port of USB-hub by the "ub" driver, and everything else by
usb-storage. One can also instruct udev to bind different wireless
drivers to identical cards - just selected by the pcmcia slot-number, and
whatever ...
To use the mentioned rules, it needs udev version 106, to be able to
write ATTR{}="$kernel" to sysfs files.
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2007-02-16 09:33:36 -07:00
|
|
|
if (!dev)
|
|
|
|
return -ENODEV;
|
2014-10-31 11:13:07 -06:00
|
|
|
if (bus_rescan_devices_helper(dev, NULL) == 0)
|
|
|
|
err = count;
|
|
|
|
put_device(dev);
|
|
|
|
return err;
|
Driver core: udev triggered device-<>driver binding
We get two per-bus sysfs files:
ls-l /sys/subsystem/usb
drwxr-xr-x 2 root root 0 2007-02-16 16:42 devices
drwxr-xr-x 7 root root 0 2007-02-16 14:55 drivers
-rw-r--r-- 1 root root 4096 2007-02-16 16:42 drivers_autoprobe
--w------- 1 root root 4096 2007-02-16 16:42 drivers_probe
The flag "drivers_autoprobe" controls the behavior of the bus to bind
devices by default, or just initialize the device and leave it alone.
The command "drivers_probe" accepts a bus_id and the bus tries to bind a
driver to this device.
Systems who want to control the driver binding with udev, switch off the
bus initiated probing:
echo 0 > /sys/subsystem/usb/drivers_autoprobe
echo 0 > /sys/subsystem/pcmcia/drivers_autoprobe
...
and initiate the probing with udev rules like:
ACTION=="add", SUBSYSTEM=="usb", ATTR{subsystem/drivers_probe}="$kernel"
ACTION=="add", SUBSYSTEM=="pcmcia", ATTR{subsystem/drivers_probe}="$kernel"
...
Custom driver binding can happen in earlier rules by something like:
ACTION=="add", SUBSYSTEM=="usb", \
ATTRS{idVendor}=="1234", ATTRS{idProduct}=="5678" \
ATTR{subsystem/drivers/<custom-driver>/bind}="$kernel"
This is intended to solve the modprobe.conf mess with "install-rules", custom
bind/unbind-scripts and all the weird things people invented over the years.
It should also provide the functionality "libusual" was supposed to do.
With udev, one can just write a udev rule to drive all USB-disks at the
third port of USB-hub by the "ub" driver, and everything else by
usb-storage. One can also instruct udev to bind different wireless
drivers to identical cards - just selected by the pcmcia slot-number, and
whatever ...
To use the mentioned rules, it needs udev version 106, to be able to
write ATTR{}="$kernel" to sysfs files.
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2007-02-16 09:33:36 -07:00
|
|
|
}
|
2005-06-22 17:09:05 -06:00
|
|
|
|
2008-01-24 23:50:12 -07:00
|
|
|
static struct device *next_device(struct klist_iter *i)
|
2005-03-21 12:49:14 -07:00
|
|
|
{
|
2008-01-24 23:50:12 -07:00
|
|
|
struct klist_node *n = klist_next(i);
|
2008-12-16 13:26:21 -07:00
|
|
|
struct device *dev = NULL;
|
|
|
|
struct device_private *dev_prv;
|
|
|
|
|
|
|
|
if (n) {
|
|
|
|
dev_prv = to_device_private_bus(n);
|
|
|
|
dev = dev_prv->device;
|
|
|
|
}
|
|
|
|
return dev;
|
2005-03-21 12:49:14 -07:00
|
|
|
}
|
|
|
|
|
2005-04-16 16:20:36 -06:00
|
|
|
/**
|
2008-01-24 23:50:12 -07:00
|
|
|
* bus_for_each_dev - device iterator.
|
|
|
|
* @bus: bus type.
|
|
|
|
* @start: device to start iterating from.
|
|
|
|
* @data: data for the callback.
|
|
|
|
* @fn: function to be called for each device.
|
2005-04-16 16:20:36 -06:00
|
|
|
*
|
2008-01-24 23:50:12 -07:00
|
|
|
* Iterate over @bus's list of devices, and call @fn for each,
|
|
|
|
* passing it @data. If @start is not NULL, we use that device to
|
|
|
|
* begin iterating from.
|
2005-04-16 16:20:36 -06:00
|
|
|
*
|
2008-01-24 23:50:12 -07:00
|
|
|
* We check the return of @fn each time. If it returns anything
|
|
|
|
* other than 0, we break out and return that value.
|
2005-04-16 16:20:36 -06:00
|
|
|
*
|
2008-01-24 23:50:12 -07:00
|
|
|
* NOTE: The device that returns a non-zero value is not retained
|
|
|
|
* in any way, nor is its refcount incremented. If the caller needs
|
2009-05-14 15:15:22 -06:00
|
|
|
* to retain this data, it should do so, and increment the reference
|
2008-01-24 23:50:12 -07:00
|
|
|
* count in the supplied callback.
|
2005-04-16 16:20:36 -06:00
|
|
|
*/
|
2008-01-24 23:50:12 -07:00
|
|
|
int bus_for_each_dev(struct bus_type *bus, struct device *start,
|
|
|
|
void *data, int (*fn)(struct device *, void *))
|
2005-04-16 16:20:36 -06:00
|
|
|
{
|
2005-03-21 12:49:14 -07:00
|
|
|
struct klist_iter i;
|
2008-01-24 23:50:12 -07:00
|
|
|
struct device *dev;
|
2005-03-21 12:49:14 -07:00
|
|
|
int error = 0;
|
2005-04-16 16:20:36 -06:00
|
|
|
|
2013-01-29 16:44:27 -07:00
|
|
|
if (!bus || !bus->p)
|
2005-03-21 12:49:14 -07:00
|
|
|
return -EINVAL;
|
|
|
|
|
2012-04-19 20:17:30 -06:00
|
|
|
klist_iter_init_node(&bus->p->klist_devices, &i,
|
|
|
|
(start ? &start->p->knode_bus : NULL));
|
|
|
|
while ((dev = next_device(&i)) && !error)
|
|
|
|
error = fn(dev, data);
|
|
|
|
klist_iter_exit(&i);
|
2005-03-21 12:49:14 -07:00
|
|
|
return error;
|
2005-04-16 16:20:36 -06:00
|
|
|
}
|
2008-01-24 23:50:12 -07:00
|
|
|
EXPORT_SYMBOL_GPL(bus_for_each_dev);
|
2005-04-16 16:20:36 -06:00
|
|
|
|
2005-06-22 08:59:51 -06:00
|
|
|
/**
|
|
|
|
* bus_find_device - device iterator for locating a particular device.
|
|
|
|
* @bus: bus type
|
|
|
|
* @start: Device to begin with
|
|
|
|
* @data: Data to pass to match function
|
|
|
|
* @match: Callback function to check device
|
|
|
|
*
|
|
|
|
* This is similar to the bus_for_each_dev() function above, but it
|
|
|
|
* returns a reference to a device that is 'found' for later use, as
|
|
|
|
* determined by the @match callback.
|
|
|
|
*
|
|
|
|
* The callback should return 0 if the device doesn't match and non-zero
|
|
|
|
* if it does. If the callback returns non-zero, this function will
|
|
|
|
* return to the caller and not iterate over any more devices.
|
|
|
|
*/
|
2008-01-24 23:50:12 -07:00
|
|
|
struct device *bus_find_device(struct bus_type *bus,
|
|
|
|
struct device *start, void *data,
|
|
|
|
int (*match)(struct device *dev, void *data))
|
2005-06-22 08:59:51 -06:00
|
|
|
{
|
|
|
|
struct klist_iter i;
|
|
|
|
struct device *dev;
|
|
|
|
|
2013-01-29 16:44:27 -07:00
|
|
|
if (!bus || !bus->p)
|
2005-06-22 08:59:51 -06:00
|
|
|
return NULL;
|
|
|
|
|
2012-04-19 20:17:30 -06:00
|
|
|
klist_iter_init_node(&bus->p->klist_devices, &i,
|
|
|
|
(start ? &start->p->knode_bus : NULL));
|
2005-06-22 08:59:51 -06:00
|
|
|
while ((dev = next_device(&i)))
|
|
|
|
if (match(dev, data) && get_device(dev))
|
|
|
|
break;
|
|
|
|
klist_iter_exit(&i);
|
|
|
|
return dev;
|
|
|
|
}
|
2008-01-24 23:50:12 -07:00
|
|
|
EXPORT_SYMBOL_GPL(bus_find_device);
|
2005-03-21 13:00:18 -07:00
|
|
|
|
2008-01-27 11:29:20 -07:00
|
|
|
static int match_name(struct device *dev, void *data)
|
|
|
|
{
|
|
|
|
const char *name = data;
|
|
|
|
|
2008-10-29 18:36:48 -06:00
|
|
|
return sysfs_streq(name, dev_name(dev));
|
2008-01-27 11:29:20 -07:00
|
|
|
}
|
|
|
|
|
|
|
|
/**
|
|
|
|
* bus_find_device_by_name - device iterator for locating a particular device of a specific name
|
|
|
|
* @bus: bus type
|
|
|
|
* @start: Device to begin with
|
|
|
|
* @name: name of the device to match
|
|
|
|
*
|
|
|
|
* This is similar to the bus_find_device() function above, but it handles
|
|
|
|
* searching by a name automatically, no need to write another strcmp matching
|
|
|
|
* function.
|
|
|
|
*/
|
|
|
|
struct device *bus_find_device_by_name(struct bus_type *bus,
|
|
|
|
struct device *start, const char *name)
|
|
|
|
{
|
|
|
|
return bus_find_device(bus, start, (void *)name, match_name);
|
|
|
|
}
|
|
|
|
EXPORT_SYMBOL_GPL(bus_find_device_by_name);
|
|
|
|
|
2011-12-14 15:29:38 -07:00
|
|
|
/**
|
|
|
|
* subsys_find_device_by_id - find a device with a specific enumeration number
|
|
|
|
* @subsys: subsystem
|
|
|
|
* @id: index 'id' in struct device
|
|
|
|
* @hint: device to check first
|
|
|
|
*
|
|
|
|
* Check the hint's next object and if it is a match return it directly,
|
|
|
|
* otherwise, fall back to a full list search. Either way a reference for
|
|
|
|
* the returned object is taken.
|
|
|
|
*/
|
|
|
|
struct device *subsys_find_device_by_id(struct bus_type *subsys, unsigned int id,
|
|
|
|
struct device *hint)
|
|
|
|
{
|
|
|
|
struct klist_iter i;
|
|
|
|
struct device *dev;
|
|
|
|
|
|
|
|
if (!subsys)
|
|
|
|
return NULL;
|
|
|
|
|
|
|
|
if (hint) {
|
2012-04-19 20:17:30 -06:00
|
|
|
klist_iter_init_node(&subsys->p->klist_devices, &i, &hint->p->knode_bus);
|
2011-12-14 15:29:38 -07:00
|
|
|
dev = next_device(&i);
|
|
|
|
if (dev && dev->id == id && get_device(dev)) {
|
|
|
|
klist_iter_exit(&i);
|
|
|
|
return dev;
|
|
|
|
}
|
|
|
|
klist_iter_exit(&i);
|
|
|
|
}
|
|
|
|
|
|
|
|
klist_iter_init_node(&subsys->p->klist_devices, &i, NULL);
|
|
|
|
while ((dev = next_device(&i))) {
|
|
|
|
if (dev->id == id && get_device(dev)) {
|
|
|
|
klist_iter_exit(&i);
|
|
|
|
return dev;
|
|
|
|
}
|
|
|
|
}
|
|
|
|
klist_iter_exit(&i);
|
|
|
|
return NULL;
|
|
|
|
}
|
|
|
|
EXPORT_SYMBOL_GPL(subsys_find_device_by_id);
|
|
|
|
|
2008-01-24 23:50:12 -07:00
|
|
|
static struct device_driver *next_driver(struct klist_iter *i)
|
2005-03-21 13:00:18 -07:00
|
|
|
{
|
2008-01-24 23:50:12 -07:00
|
|
|
struct klist_node *n = klist_next(i);
|
2007-11-28 16:59:15 -07:00
|
|
|
struct driver_private *drv_priv;
|
|
|
|
|
|
|
|
if (n) {
|
|
|
|
drv_priv = container_of(n, struct driver_private, knode_bus);
|
|
|
|
return drv_priv->driver;
|
|
|
|
}
|
|
|
|
return NULL;
|
2005-03-21 13:00:18 -07:00
|
|
|
}
|
|
|
|
|
2005-04-16 16:20:36 -06:00
|
|
|
/**
|
2008-01-24 23:50:12 -07:00
|
|
|
* bus_for_each_drv - driver iterator
|
|
|
|
* @bus: bus we're dealing with.
|
|
|
|
* @start: driver to start iterating on.
|
|
|
|
* @data: data to pass to the callback.
|
|
|
|
* @fn: function to call for each driver.
|
2005-04-16 16:20:36 -06:00
|
|
|
*
|
2008-01-24 23:50:12 -07:00
|
|
|
* This is nearly identical to the device iterator above.
|
|
|
|
* We iterate over each driver that belongs to @bus, and call
|
|
|
|
* @fn for each. If @fn returns anything but 0, we break out
|
|
|
|
* and return it. If @start is not NULL, we use it as the head
|
|
|
|
* of the list.
|
2005-04-16 16:20:36 -06:00
|
|
|
*
|
2008-01-24 23:50:12 -07:00
|
|
|
* NOTE: we don't return the driver that returns a non-zero
|
|
|
|
* value, nor do we leave the reference count incremented for that
|
|
|
|
* driver. If the caller needs to know that info, it must set it
|
|
|
|
* in the callback. It must also be sure to increment the refcount
|
|
|
|
* so it doesn't disappear before returning to the caller.
|
2005-04-16 16:20:36 -06:00
|
|
|
*/
|
2008-01-24 23:50:12 -07:00
|
|
|
int bus_for_each_drv(struct bus_type *bus, struct device_driver *start,
|
|
|
|
void *data, int (*fn)(struct device_driver *, void *))
|
2005-04-16 16:20:36 -06:00
|
|
|
{
|
2005-03-21 13:00:18 -07:00
|
|
|
struct klist_iter i;
|
2008-01-24 23:50:12 -07:00
|
|
|
struct device_driver *drv;
|
2005-03-21 13:00:18 -07:00
|
|
|
int error = 0;
|
2005-04-16 16:20:36 -06:00
|
|
|
|
2005-03-21 13:00:18 -07:00
|
|
|
if (!bus)
|
|
|
|
return -EINVAL;
|
|
|
|
|
2012-04-19 20:17:30 -06:00
|
|
|
klist_iter_init_node(&bus->p->klist_drivers, &i,
|
|
|
|
start ? &start->p->knode_bus : NULL);
|
|
|
|
while ((drv = next_driver(&i)) && !error)
|
|
|
|
error = fn(drv, data);
|
|
|
|
klist_iter_exit(&i);
|
2005-03-21 13:00:18 -07:00
|
|
|
return error;
|
2005-04-16 16:20:36 -06:00
|
|
|
}
|
2008-01-24 23:50:12 -07:00
|
|
|
EXPORT_SYMBOL_GPL(bus_for_each_drv);
|
2005-04-16 16:20:36 -06:00
|
|
|
|
2007-02-13 23:39:26 -07:00
|
|
|
static int device_add_attrs(struct bus_type *bus, struct device *dev)
|
2005-04-16 16:20:36 -06:00
|
|
|
{
|
|
|
|
int error = 0;
|
|
|
|
int i;
|
|
|
|
|
2007-02-13 23:39:26 -07:00
|
|
|
if (!bus->dev_attrs)
|
|
|
|
return 0;
|
|
|
|
|
2013-08-22 11:25:34 -06:00
|
|
|
for (i = 0; bus->dev_attrs[i].attr.name; i++) {
|
2008-01-24 23:50:12 -07:00
|
|
|
error = device_create_file(dev, &bus->dev_attrs[i]);
|
2007-02-13 23:39:26 -07:00
|
|
|
if (error) {
|
|
|
|
while (--i >= 0)
|
|
|
|
device_remove_file(dev, &bus->dev_attrs[i]);
|
|
|
|
break;
|
2005-04-16 16:20:36 -06:00
|
|
|
}
|
|
|
|
}
|
|
|
|
return error;
|
|
|
|
}
|
|
|
|
|
2008-01-24 23:50:12 -07:00
|
|
|
static void device_remove_attrs(struct bus_type *bus, struct device *dev)
|
2005-04-16 16:20:36 -06:00
|
|
|
{
|
|
|
|
int i;
|
|
|
|
|
|
|
|
if (bus->dev_attrs) {
|
2013-08-22 11:25:34 -06:00
|
|
|
for (i = 0; bus->dev_attrs[i].attr.name; i++)
|
2008-01-24 23:50:12 -07:00
|
|
|
device_remove_file(dev, &bus->dev_attrs[i]);
|
2005-04-16 16:20:36 -06:00
|
|
|
}
|
|
|
|
}
|
|
|
|
|
|
|
|
/**
|
2008-01-24 23:50:12 -07:00
|
|
|
* bus_add_device - add device to bus
|
|
|
|
* @dev: device being added
|
2005-04-16 16:20:36 -06:00
|
|
|
*
|
2009-07-30 13:27:18 -06:00
|
|
|
* - Add device's bus attributes.
|
|
|
|
* - Create links to device's bus.
|
2008-01-24 23:50:12 -07:00
|
|
|
* - Add the device to its bus's list of devices.
|
2005-04-16 16:20:36 -06:00
|
|
|
*/
|
2008-01-24 23:50:12 -07:00
|
|
|
int bus_add_device(struct device *dev)
|
2005-04-16 16:20:36 -06:00
|
|
|
{
|
2008-01-24 23:50:12 -07:00
|
|
|
struct bus_type *bus = bus_get(dev->bus);
|
2005-04-16 16:20:36 -06:00
|
|
|
int error = 0;
|
|
|
|
|
|
|
|
if (bus) {
|
2008-10-29 18:36:48 -06:00
|
|
|
pr_debug("bus: '%s': add device %s\n", bus->name, dev_name(dev));
|
2005-06-22 17:09:05 -06:00
|
|
|
error = device_add_attrs(bus, dev);
|
2006-08-14 23:43:20 -06:00
|
|
|
if (error)
|
2006-09-22 03:37:08 -06:00
|
|
|
goto out_put;
|
2013-08-08 16:22:55 -06:00
|
|
|
error = device_add_groups(dev, bus->dev_groups);
|
|
|
|
if (error)
|
2015-01-27 19:02:44 -07:00
|
|
|
goto out_id;
|
2007-11-01 20:41:16 -06:00
|
|
|
error = sysfs_create_link(&bus->p->devices_kset->kobj,
|
2008-10-29 18:36:48 -06:00
|
|
|
&dev->kobj, dev_name(dev));
|
2006-08-14 23:43:20 -06:00
|
|
|
if (error)
|
2015-01-27 19:02:44 -07:00
|
|
|
goto out_groups;
|
2006-08-14 23:43:20 -06:00
|
|
|
error = sysfs_create_link(&dev->kobj,
|
2007-11-01 20:41:16 -06:00
|
|
|
&dev->bus->p->subsys.kobj, "subsystem");
|
2006-08-14 23:43:20 -06:00
|
|
|
if (error)
|
2006-09-22 03:37:08 -06:00
|
|
|
goto out_subsys;
|
2009-07-30 13:27:18 -06:00
|
|
|
klist_add_tail(&dev->p->knode_bus, &bus->p->klist_devices);
|
2005-04-16 16:20:36 -06:00
|
|
|
}
|
2006-09-22 03:37:08 -06:00
|
|
|
return 0;
|
|
|
|
|
|
|
|
out_subsys:
|
2008-10-29 18:36:48 -06:00
|
|
|
sysfs_remove_link(&bus->p->devices_kset->kobj, dev_name(dev));
|
2013-08-08 16:22:55 -06:00
|
|
|
out_groups:
|
|
|
|
device_remove_groups(dev, bus->dev_groups);
|
2006-09-22 03:37:08 -06:00
|
|
|
out_id:
|
|
|
|
device_remove_attrs(bus, dev);
|
|
|
|
out_put:
|
2007-09-13 03:53:13 -06:00
|
|
|
bus_put(dev->bus);
|
2005-04-16 16:20:36 -06:00
|
|
|
return error;
|
|
|
|
}
|
|
|
|
|
2006-04-04 12:42:26 -06:00
|
|
|
/**
|
2009-07-30 13:27:18 -06:00
|
|
|
* bus_probe_device - probe drivers for a new device
|
|
|
|
* @dev: device to probe
|
2006-04-04 12:42:26 -06:00
|
|
|
*
|
2009-07-30 13:27:18 -06:00
|
|
|
* - Automatically probe for a driver if the bus allows it.
|
2006-04-04 12:42:26 -06:00
|
|
|
*/
|
2009-07-30 13:27:18 -06:00
|
|
|
void bus_probe_device(struct device *dev)
|
2006-04-04 12:42:26 -06:00
|
|
|
{
|
2006-08-14 23:43:20 -06:00
|
|
|
struct bus_type *bus = dev->bus;
|
2011-12-14 15:29:38 -07:00
|
|
|
struct subsys_interface *sif;
|
2009-07-30 13:27:18 -06:00
|
|
|
int ret;
|
2006-04-04 12:42:26 -06:00
|
|
|
|
2011-12-14 15:29:38 -07:00
|
|
|
if (!bus)
|
|
|
|
return;
|
|
|
|
|
|
|
|
if (bus->p->drivers_autoprobe) {
|
2009-07-30 13:27:18 -06:00
|
|
|
ret = device_attach(dev);
|
2007-02-05 17:15:26 -07:00
|
|
|
WARN_ON(ret < 0);
|
2006-04-04 12:42:26 -06:00
|
|
|
}
|
2011-12-14 15:29:38 -07:00
|
|
|
|
|
|
|
mutex_lock(&bus->p->mutex);
|
|
|
|
list_for_each_entry(sif, &bus->p->interfaces, node)
|
|
|
|
if (sif->add_dev)
|
|
|
|
sif->add_dev(dev, sif);
|
|
|
|
mutex_unlock(&bus->p->mutex);
|
2006-04-04 12:42:26 -06:00
|
|
|
}
|
|
|
|
|
2005-04-16 16:20:36 -06:00
|
|
|
/**
|
2008-01-24 23:50:12 -07:00
|
|
|
* bus_remove_device - remove device from bus
|
|
|
|
* @dev: device to be removed
|
2005-04-16 16:20:36 -06:00
|
|
|
*
|
2011-12-14 15:29:38 -07:00
|
|
|
* - Remove device from all interfaces.
|
|
|
|
* - Remove symlink from bus' directory.
|
2008-01-24 23:50:12 -07:00
|
|
|
* - Delete device from bus's list.
|
|
|
|
* - Detach from its driver.
|
|
|
|
* - Drop reference taken in bus_add_device().
|
2005-04-16 16:20:36 -06:00
|
|
|
*/
|
2008-01-24 23:50:12 -07:00
|
|
|
void bus_remove_device(struct device *dev)
|
2005-04-16 16:20:36 -06:00
|
|
|
{
|
2011-12-14 15:29:38 -07:00
|
|
|
struct bus_type *bus = dev->bus;
|
|
|
|
struct subsys_interface *sif;
|
|
|
|
|
|
|
|
if (!bus)
|
|
|
|
return;
|
|
|
|
|
|
|
|
mutex_lock(&bus->p->mutex);
|
|
|
|
list_for_each_entry(sif, &bus->p->interfaces, node)
|
|
|
|
if (sif->remove_dev)
|
|
|
|
sif->remove_dev(dev, sif);
|
|
|
|
mutex_unlock(&bus->p->mutex);
|
|
|
|
|
|
|
|
sysfs_remove_link(&dev->kobj, "subsystem");
|
|
|
|
sysfs_remove_link(&dev->bus->p->devices_kset->kobj,
|
|
|
|
dev_name(dev));
|
|
|
|
device_remove_attrs(dev->bus, dev);
|
2013-08-08 16:22:55 -06:00
|
|
|
device_remove_groups(dev, dev->bus->dev_groups);
|
2011-12-14 15:29:38 -07:00
|
|
|
if (klist_node_attached(&dev->p->knode_bus))
|
|
|
|
klist_del(&dev->p->knode_bus);
|
|
|
|
|
|
|
|
pr_debug("bus: '%s': remove device %s\n",
|
|
|
|
dev->bus->name, dev_name(dev));
|
|
|
|
device_release_driver(dev);
|
|
|
|
bus_put(dev->bus);
|
2005-04-16 16:20:36 -06:00
|
|
|
}
|
|
|
|
|
2006-08-14 23:43:20 -06:00
|
|
|
static int __must_check add_bind_files(struct device_driver *drv)
|
2005-12-13 16:17:34 -07:00
|
|
|
{
|
2006-08-14 23:43:20 -06:00
|
|
|
int ret;
|
|
|
|
|
|
|
|
ret = driver_create_file(drv, &driver_attr_unbind);
|
|
|
|
if (ret == 0) {
|
|
|
|
ret = driver_create_file(drv, &driver_attr_bind);
|
|
|
|
if (ret)
|
|
|
|
driver_remove_file(drv, &driver_attr_unbind);
|
|
|
|
}
|
|
|
|
return ret;
|
2005-12-13 16:17:34 -07:00
|
|
|
}
|
|
|
|
|
|
|
|
static void remove_bind_files(struct device_driver *drv)
|
|
|
|
{
|
|
|
|
driver_remove_file(drv, &driver_attr_bind);
|
|
|
|
driver_remove_file(drv, &driver_attr_unbind);
|
|
|
|
}
|
Driver core: udev triggered device-<>driver binding
We get two per-bus sysfs files:
ls-l /sys/subsystem/usb
drwxr-xr-x 2 root root 0 2007-02-16 16:42 devices
drwxr-xr-x 7 root root 0 2007-02-16 14:55 drivers
-rw-r--r-- 1 root root 4096 2007-02-16 16:42 drivers_autoprobe
--w------- 1 root root 4096 2007-02-16 16:42 drivers_probe
The flag "drivers_autoprobe" controls the behavior of the bus to bind
devices by default, or just initialize the device and leave it alone.
The command "drivers_probe" accepts a bus_id and the bus tries to bind a
driver to this device.
Systems who want to control the driver binding with udev, switch off the
bus initiated probing:
echo 0 > /sys/subsystem/usb/drivers_autoprobe
echo 0 > /sys/subsystem/pcmcia/drivers_autoprobe
...
and initiate the probing with udev rules like:
ACTION=="add", SUBSYSTEM=="usb", ATTR{subsystem/drivers_probe}="$kernel"
ACTION=="add", SUBSYSTEM=="pcmcia", ATTR{subsystem/drivers_probe}="$kernel"
...
Custom driver binding can happen in earlier rules by something like:
ACTION=="add", SUBSYSTEM=="usb", \
ATTRS{idVendor}=="1234", ATTRS{idProduct}=="5678" \
ATTR{subsystem/drivers/<custom-driver>/bind}="$kernel"
This is intended to solve the modprobe.conf mess with "install-rules", custom
bind/unbind-scripts and all the weird things people invented over the years.
It should also provide the functionality "libusual" was supposed to do.
With udev, one can just write a udev rule to drive all USB-disks at the
third port of USB-hub by the "ub" driver, and everything else by
usb-storage. One can also instruct udev to bind different wireless
drivers to identical cards - just selected by the pcmcia slot-number, and
whatever ...
To use the mentioned rules, it needs udev version 106, to be able to
write ATTR{}="$kernel" to sysfs files.
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2007-02-16 09:33:36 -07:00
|
|
|
|
2007-07-29 18:28:56 -06:00
|
|
|
static BUS_ATTR(drivers_probe, S_IWUSR, NULL, store_drivers_probe);
|
|
|
|
static BUS_ATTR(drivers_autoprobe, S_IWUSR | S_IRUGO,
|
|
|
|
show_drivers_autoprobe, store_drivers_autoprobe);
|
|
|
|
|
Driver core: udev triggered device-<>driver binding
We get two per-bus sysfs files:
ls-l /sys/subsystem/usb
drwxr-xr-x 2 root root 0 2007-02-16 16:42 devices
drwxr-xr-x 7 root root 0 2007-02-16 14:55 drivers
-rw-r--r-- 1 root root 4096 2007-02-16 16:42 drivers_autoprobe
--w------- 1 root root 4096 2007-02-16 16:42 drivers_probe
The flag "drivers_autoprobe" controls the behavior of the bus to bind
devices by default, or just initialize the device and leave it alone.
The command "drivers_probe" accepts a bus_id and the bus tries to bind a
driver to this device.
Systems who want to control the driver binding with udev, switch off the
bus initiated probing:
echo 0 > /sys/subsystem/usb/drivers_autoprobe
echo 0 > /sys/subsystem/pcmcia/drivers_autoprobe
...
and initiate the probing with udev rules like:
ACTION=="add", SUBSYSTEM=="usb", ATTR{subsystem/drivers_probe}="$kernel"
ACTION=="add", SUBSYSTEM=="pcmcia", ATTR{subsystem/drivers_probe}="$kernel"
...
Custom driver binding can happen in earlier rules by something like:
ACTION=="add", SUBSYSTEM=="usb", \
ATTRS{idVendor}=="1234", ATTRS{idProduct}=="5678" \
ATTR{subsystem/drivers/<custom-driver>/bind}="$kernel"
This is intended to solve the modprobe.conf mess with "install-rules", custom
bind/unbind-scripts and all the weird things people invented over the years.
It should also provide the functionality "libusual" was supposed to do.
With udev, one can just write a udev rule to drive all USB-disks at the
third port of USB-hub by the "ub" driver, and everything else by
usb-storage. One can also instruct udev to bind different wireless
drivers to identical cards - just selected by the pcmcia slot-number, and
whatever ...
To use the mentioned rules, it needs udev version 106, to be able to
write ATTR{}="$kernel" to sysfs files.
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2007-02-16 09:33:36 -07:00
|
|
|
static int add_probe_files(struct bus_type *bus)
|
|
|
|
{
|
|
|
|
int retval;
|
|
|
|
|
2007-07-29 18:28:56 -06:00
|
|
|
retval = bus_create_file(bus, &bus_attr_drivers_probe);
|
Driver core: udev triggered device-<>driver binding
We get two per-bus sysfs files:
ls-l /sys/subsystem/usb
drwxr-xr-x 2 root root 0 2007-02-16 16:42 devices
drwxr-xr-x 7 root root 0 2007-02-16 14:55 drivers
-rw-r--r-- 1 root root 4096 2007-02-16 16:42 drivers_autoprobe
--w------- 1 root root 4096 2007-02-16 16:42 drivers_probe
The flag "drivers_autoprobe" controls the behavior of the bus to bind
devices by default, or just initialize the device and leave it alone.
The command "drivers_probe" accepts a bus_id and the bus tries to bind a
driver to this device.
Systems who want to control the driver binding with udev, switch off the
bus initiated probing:
echo 0 > /sys/subsystem/usb/drivers_autoprobe
echo 0 > /sys/subsystem/pcmcia/drivers_autoprobe
...
and initiate the probing with udev rules like:
ACTION=="add", SUBSYSTEM=="usb", ATTR{subsystem/drivers_probe}="$kernel"
ACTION=="add", SUBSYSTEM=="pcmcia", ATTR{subsystem/drivers_probe}="$kernel"
...
Custom driver binding can happen in earlier rules by something like:
ACTION=="add", SUBSYSTEM=="usb", \
ATTRS{idVendor}=="1234", ATTRS{idProduct}=="5678" \
ATTR{subsystem/drivers/<custom-driver>/bind}="$kernel"
This is intended to solve the modprobe.conf mess with "install-rules", custom
bind/unbind-scripts and all the weird things people invented over the years.
It should also provide the functionality "libusual" was supposed to do.
With udev, one can just write a udev rule to drive all USB-disks at the
third port of USB-hub by the "ub" driver, and everything else by
usb-storage. One can also instruct udev to bind different wireless
drivers to identical cards - just selected by the pcmcia slot-number, and
whatever ...
To use the mentioned rules, it needs udev version 106, to be able to
write ATTR{}="$kernel" to sysfs files.
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2007-02-16 09:33:36 -07:00
|
|
|
if (retval)
|
|
|
|
goto out;
|
|
|
|
|
2007-07-29 18:28:56 -06:00
|
|
|
retval = bus_create_file(bus, &bus_attr_drivers_autoprobe);
|
Driver core: udev triggered device-<>driver binding
We get two per-bus sysfs files:
ls-l /sys/subsystem/usb
drwxr-xr-x 2 root root 0 2007-02-16 16:42 devices
drwxr-xr-x 7 root root 0 2007-02-16 14:55 drivers
-rw-r--r-- 1 root root 4096 2007-02-16 16:42 drivers_autoprobe
--w------- 1 root root 4096 2007-02-16 16:42 drivers_probe
The flag "drivers_autoprobe" controls the behavior of the bus to bind
devices by default, or just initialize the device and leave it alone.
The command "drivers_probe" accepts a bus_id and the bus tries to bind a
driver to this device.
Systems who want to control the driver binding with udev, switch off the
bus initiated probing:
echo 0 > /sys/subsystem/usb/drivers_autoprobe
echo 0 > /sys/subsystem/pcmcia/drivers_autoprobe
...
and initiate the probing with udev rules like:
ACTION=="add", SUBSYSTEM=="usb", ATTR{subsystem/drivers_probe}="$kernel"
ACTION=="add", SUBSYSTEM=="pcmcia", ATTR{subsystem/drivers_probe}="$kernel"
...
Custom driver binding can happen in earlier rules by something like:
ACTION=="add", SUBSYSTEM=="usb", \
ATTRS{idVendor}=="1234", ATTRS{idProduct}=="5678" \
ATTR{subsystem/drivers/<custom-driver>/bind}="$kernel"
This is intended to solve the modprobe.conf mess with "install-rules", custom
bind/unbind-scripts and all the weird things people invented over the years.
It should also provide the functionality "libusual" was supposed to do.
With udev, one can just write a udev rule to drive all USB-disks at the
third port of USB-hub by the "ub" driver, and everything else by
usb-storage. One can also instruct udev to bind different wireless
drivers to identical cards - just selected by the pcmcia slot-number, and
whatever ...
To use the mentioned rules, it needs udev version 106, to be able to
write ATTR{}="$kernel" to sysfs files.
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2007-02-16 09:33:36 -07:00
|
|
|
if (retval)
|
2007-07-29 18:28:56 -06:00
|
|
|
bus_remove_file(bus, &bus_attr_drivers_probe);
|
Driver core: udev triggered device-<>driver binding
We get two per-bus sysfs files:
ls-l /sys/subsystem/usb
drwxr-xr-x 2 root root 0 2007-02-16 16:42 devices
drwxr-xr-x 7 root root 0 2007-02-16 14:55 drivers
-rw-r--r-- 1 root root 4096 2007-02-16 16:42 drivers_autoprobe
--w------- 1 root root 4096 2007-02-16 16:42 drivers_probe
The flag "drivers_autoprobe" controls the behavior of the bus to bind
devices by default, or just initialize the device and leave it alone.
The command "drivers_probe" accepts a bus_id and the bus tries to bind a
driver to this device.
Systems who want to control the driver binding with udev, switch off the
bus initiated probing:
echo 0 > /sys/subsystem/usb/drivers_autoprobe
echo 0 > /sys/subsystem/pcmcia/drivers_autoprobe
...
and initiate the probing with udev rules like:
ACTION=="add", SUBSYSTEM=="usb", ATTR{subsystem/drivers_probe}="$kernel"
ACTION=="add", SUBSYSTEM=="pcmcia", ATTR{subsystem/drivers_probe}="$kernel"
...
Custom driver binding can happen in earlier rules by something like:
ACTION=="add", SUBSYSTEM=="usb", \
ATTRS{idVendor}=="1234", ATTRS{idProduct}=="5678" \
ATTR{subsystem/drivers/<custom-driver>/bind}="$kernel"
This is intended to solve the modprobe.conf mess with "install-rules", custom
bind/unbind-scripts and all the weird things people invented over the years.
It should also provide the functionality "libusual" was supposed to do.
With udev, one can just write a udev rule to drive all USB-disks at the
third port of USB-hub by the "ub" driver, and everything else by
usb-storage. One can also instruct udev to bind different wireless
drivers to identical cards - just selected by the pcmcia slot-number, and
whatever ...
To use the mentioned rules, it needs udev version 106, to be able to
write ATTR{}="$kernel" to sysfs files.
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2007-02-16 09:33:36 -07:00
|
|
|
out:
|
|
|
|
return retval;
|
|
|
|
}
|
|
|
|
|
|
|
|
static void remove_probe_files(struct bus_type *bus)
|
|
|
|
{
|
2007-07-29 18:28:56 -06:00
|
|
|
bus_remove_file(bus, &bus_attr_drivers_autoprobe);
|
|
|
|
bus_remove_file(bus, &bus_attr_drivers_probe);
|
Driver core: udev triggered device-<>driver binding
We get two per-bus sysfs files:
ls-l /sys/subsystem/usb
drwxr-xr-x 2 root root 0 2007-02-16 16:42 devices
drwxr-xr-x 7 root root 0 2007-02-16 14:55 drivers
-rw-r--r-- 1 root root 4096 2007-02-16 16:42 drivers_autoprobe
--w------- 1 root root 4096 2007-02-16 16:42 drivers_probe
The flag "drivers_autoprobe" controls the behavior of the bus to bind
devices by default, or just initialize the device and leave it alone.
The command "drivers_probe" accepts a bus_id and the bus tries to bind a
driver to this device.
Systems who want to control the driver binding with udev, switch off the
bus initiated probing:
echo 0 > /sys/subsystem/usb/drivers_autoprobe
echo 0 > /sys/subsystem/pcmcia/drivers_autoprobe
...
and initiate the probing with udev rules like:
ACTION=="add", SUBSYSTEM=="usb", ATTR{subsystem/drivers_probe}="$kernel"
ACTION=="add", SUBSYSTEM=="pcmcia", ATTR{subsystem/drivers_probe}="$kernel"
...
Custom driver binding can happen in earlier rules by something like:
ACTION=="add", SUBSYSTEM=="usb", \
ATTRS{idVendor}=="1234", ATTRS{idProduct}=="5678" \
ATTR{subsystem/drivers/<custom-driver>/bind}="$kernel"
This is intended to solve the modprobe.conf mess with "install-rules", custom
bind/unbind-scripts and all the weird things people invented over the years.
It should also provide the functionality "libusual" was supposed to do.
With udev, one can just write a udev rule to drive all USB-disks at the
third port of USB-hub by the "ub" driver, and everything else by
usb-storage. One can also instruct udev to bind different wireless
drivers to identical cards - just selected by the pcmcia slot-number, and
whatever ...
To use the mentioned rules, it needs udev version 106, to be able to
write ATTR{}="$kernel" to sysfs files.
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2007-02-16 09:33:36 -07:00
|
|
|
}
|
2005-04-16 16:20:36 -06:00
|
|
|
|
2013-08-23 16:04:42 -06:00
|
|
|
static ssize_t uevent_store(struct device_driver *drv, const char *buf,
|
|
|
|
size_t count)
|
2007-08-12 12:43:55 -06:00
|
|
|
{
|
|
|
|
enum kobject_action action;
|
|
|
|
|
|
|
|
if (kobject_action_type(buf, count, &action) == 0)
|
2007-11-28 16:59:15 -07:00
|
|
|
kobject_uevent(&drv->p->kobj, action);
|
2007-08-12 12:43:55 -06:00
|
|
|
return count;
|
|
|
|
}
|
2013-08-23 16:04:42 -06:00
|
|
|
static DRIVER_ATTR_WO(uevent);
|
2007-08-12 12:43:55 -06:00
|
|
|
|
2005-04-16 16:20:36 -06:00
|
|
|
/**
|
2008-01-24 23:50:12 -07:00
|
|
|
* bus_add_driver - Add a driver to the bus.
|
|
|
|
* @drv: driver.
|
2005-04-16 16:20:36 -06:00
|
|
|
*/
|
2006-08-14 23:43:20 -06:00
|
|
|
int bus_add_driver(struct device_driver *drv)
|
2005-04-16 16:20:36 -06:00
|
|
|
{
|
2007-11-28 16:59:15 -07:00
|
|
|
struct bus_type *bus;
|
|
|
|
struct driver_private *priv;
|
2005-04-16 16:20:36 -06:00
|
|
|
int error = 0;
|
|
|
|
|
2007-11-28 16:59:15 -07:00
|
|
|
bus = bus_get(drv->bus);
|
2006-10-04 05:48:03 -06:00
|
|
|
if (!bus)
|
2007-04-20 12:29:52 -06:00
|
|
|
return -EINVAL;
|
2006-10-04 05:48:03 -06:00
|
|
|
|
2007-11-29 00:49:41 -07:00
|
|
|
pr_debug("bus: '%s': add driver %s\n", bus->name, drv->name);
|
2007-11-28 16:59:15 -07:00
|
|
|
|
|
|
|
priv = kzalloc(sizeof(*priv), GFP_KERNEL);
|
2008-02-18 09:04:25 -07:00
|
|
|
if (!priv) {
|
|
|
|
error = -ENOMEM;
|
|
|
|
goto out_put_bus;
|
|
|
|
}
|
2007-11-28 16:59:15 -07:00
|
|
|
klist_init(&priv->klist_devices, NULL, NULL);
|
|
|
|
priv->driver = drv;
|
|
|
|
drv->p = priv;
|
2007-12-17 12:54:39 -07:00
|
|
|
priv->kobj.kset = bus->p->drivers_kset;
|
|
|
|
error = kobject_init_and_add(&priv->kobj, &driver_ktype, NULL,
|
|
|
|
"%s", drv->name);
|
2007-07-09 12:39:18 -06:00
|
|
|
if (error)
|
2008-02-18 09:04:25 -07:00
|
|
|
goto out_unregister;
|
2006-10-04 05:48:03 -06:00
|
|
|
|
2012-11-19 08:35:17 -07:00
|
|
|
klist_add_tail(&priv->knode_bus, &bus->p->klist_drivers);
|
2007-11-01 20:41:16 -06:00
|
|
|
if (drv->bus->p->drivers_autoprobe) {
|
Driver core: udev triggered device-<>driver binding
We get two per-bus sysfs files:
ls-l /sys/subsystem/usb
drwxr-xr-x 2 root root 0 2007-02-16 16:42 devices
drwxr-xr-x 7 root root 0 2007-02-16 14:55 drivers
-rw-r--r-- 1 root root 4096 2007-02-16 16:42 drivers_autoprobe
--w------- 1 root root 4096 2007-02-16 16:42 drivers_probe
The flag "drivers_autoprobe" controls the behavior of the bus to bind
devices by default, or just initialize the device and leave it alone.
The command "drivers_probe" accepts a bus_id and the bus tries to bind a
driver to this device.
Systems who want to control the driver binding with udev, switch off the
bus initiated probing:
echo 0 > /sys/subsystem/usb/drivers_autoprobe
echo 0 > /sys/subsystem/pcmcia/drivers_autoprobe
...
and initiate the probing with udev rules like:
ACTION=="add", SUBSYSTEM=="usb", ATTR{subsystem/drivers_probe}="$kernel"
ACTION=="add", SUBSYSTEM=="pcmcia", ATTR{subsystem/drivers_probe}="$kernel"
...
Custom driver binding can happen in earlier rules by something like:
ACTION=="add", SUBSYSTEM=="usb", \
ATTRS{idVendor}=="1234", ATTRS{idProduct}=="5678" \
ATTR{subsystem/drivers/<custom-driver>/bind}="$kernel"
This is intended to solve the modprobe.conf mess with "install-rules", custom
bind/unbind-scripts and all the weird things people invented over the years.
It should also provide the functionality "libusual" was supposed to do.
With udev, one can just write a udev rule to drive all USB-disks at the
third port of USB-hub by the "ub" driver, and everything else by
usb-storage. One can also instruct udev to bind different wireless
drivers to identical cards - just selected by the pcmcia slot-number, and
whatever ...
To use the mentioned rules, it needs udev version 106, to be able to
write ATTR{}="$kernel" to sysfs files.
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2007-02-16 09:33:36 -07:00
|
|
|
error = driver_attach(drv);
|
|
|
|
if (error)
|
|
|
|
goto out_unregister;
|
|
|
|
}
|
2006-10-04 05:48:03 -06:00
|
|
|
module_add_driver(drv->owner, drv);
|
|
|
|
|
2007-08-12 12:43:55 -06:00
|
|
|
error = driver_create_file(drv, &driver_attr_uevent);
|
|
|
|
if (error) {
|
|
|
|
printk(KERN_ERR "%s: uevent attr (%s) failed\n",
|
2008-03-04 17:41:05 -07:00
|
|
|
__func__, drv->name);
|
2007-08-12 12:43:55 -06:00
|
|
|
}
|
2013-09-27 22:47:21 -06:00
|
|
|
error = driver_add_groups(drv, bus->drv_groups);
|
2006-10-04 05:48:03 -06:00
|
|
|
if (error) {
|
|
|
|
/* How the hell do we get out of this pickle? Give up */
|
2013-08-08 16:22:56 -06:00
|
|
|
printk(KERN_ERR "%s: driver_create_groups(%s) failed\n",
|
|
|
|
__func__, drv->name);
|
2013-09-27 22:47:21 -06:00
|
|
|
}
|
2009-10-12 21:17:41 -06:00
|
|
|
|
|
|
|
if (!drv->suppress_bind_attrs) {
|
|
|
|
error = add_bind_files(drv);
|
|
|
|
if (error) {
|
|
|
|
/* Ditto */
|
|
|
|
printk(KERN_ERR "%s: add_bind_files(%s) failed\n",
|
|
|
|
__func__, drv->name);
|
|
|
|
}
|
2005-04-16 16:20:36 -06:00
|
|
|
}
|
2006-10-04 05:48:03 -06:00
|
|
|
|
2009-05-28 15:24:07 -06:00
|
|
|
return 0;
|
2009-10-12 21:17:41 -06:00
|
|
|
|
2006-08-14 23:43:20 -06:00
|
|
|
out_unregister:
|
2009-12-14 11:28:12 -07:00
|
|
|
kobject_put(&priv->kobj);
|
2009-05-28 15:24:07 -06:00
|
|
|
kfree(drv->p);
|
|
|
|
drv->p = NULL;
|
2006-08-14 23:43:20 -06:00
|
|
|
out_put_bus:
|
2007-09-13 03:53:13 -06:00
|
|
|
bus_put(bus);
|
2006-08-14 23:43:20 -06:00
|
|
|
return error;
|
2005-04-16 16:20:36 -06:00
|
|
|
}
|
|
|
|
|
|
|
|
/**
|
2008-01-24 23:50:12 -07:00
|
|
|
* bus_remove_driver - delete driver from bus's knowledge.
|
|
|
|
* @drv: driver.
|
2005-04-16 16:20:36 -06:00
|
|
|
*
|
2008-01-24 23:50:12 -07:00
|
|
|
* Detach the driver from the devices it controls, and remove
|
|
|
|
* it from its bus's list of drivers. Finally, we drop the reference
|
|
|
|
* to the bus we took in bus_add_driver().
|
2005-04-16 16:20:36 -06:00
|
|
|
*/
|
2008-01-24 23:50:12 -07:00
|
|
|
void bus_remove_driver(struct device_driver *drv)
|
2005-04-16 16:20:36 -06:00
|
|
|
{
|
2006-10-04 05:48:03 -06:00
|
|
|
if (!drv->bus)
|
|
|
|
return;
|
|
|
|
|
2009-10-12 21:17:41 -06:00
|
|
|
if (!drv->suppress_bind_attrs)
|
|
|
|
remove_bind_files(drv);
|
2013-08-08 16:22:56 -06:00
|
|
|
driver_remove_groups(drv, drv->bus->drv_groups);
|
2007-08-12 12:43:55 -06:00
|
|
|
driver_remove_file(drv, &driver_attr_uevent);
|
2007-11-28 16:59:15 -07:00
|
|
|
klist_remove(&drv->p->knode_bus);
|
2007-11-29 00:49:41 -07:00
|
|
|
pr_debug("bus: '%s': remove driver %s\n", drv->bus->name, drv->name);
|
2006-10-04 05:48:03 -06:00
|
|
|
driver_detach(drv);
|
|
|
|
module_remove_driver(drv);
|
2007-12-20 09:13:05 -07:00
|
|
|
kobject_put(&drv->p->kobj);
|
2007-09-13 03:53:13 -06:00
|
|
|
bus_put(drv->bus);
|
2005-04-16 16:20:36 -06:00
|
|
|
}
|
|
|
|
|
|
|
|
/* Helper for bus_rescan_devices's iter */
|
2006-08-14 23:43:20 -06:00
|
|
|
static int __must_check bus_rescan_devices_helper(struct device *dev,
|
2008-01-24 23:50:12 -07:00
|
|
|
void *data)
|
2005-04-16 16:20:36 -06:00
|
|
|
{
|
2006-08-14 23:43:20 -06:00
|
|
|
int ret = 0;
|
|
|
|
|
[PATCH] Hold the device's parent's lock during probe and remove
This patch (as604) makes the driver core hold a device's parent's lock
as well as the device's lock during calls to the probe and remove
methods in a driver. This facility is needed by USB device drivers,
owing to the peculiar way USB devices work:
A device provides multiple interfaces, and drivers are bound
to interfaces rather than to devices;
Nevertheless a reset, reset-configuration, suspend, or resume
affects the entire device and requires the caller to hold the
lock for the device, not just a lock for one of the interfaces.
Since a USB driver's probe method is always called with the interface
lock held, the locking order rules (always lock parent before child)
prevent these methods from acquiring the device lock. The solution
provided here is to call all probe and remove methods, for all devices
(not just USB), with the parent lock already acquired.
Although currently only the USB subsystem requires these changes, people
have mentioned in prior discussion that the overhead of acquiring an
extra semaphore in all the prove/remove sequences is not overly large.
Up to now, the USB core has been using its own set of private
semaphores. A followup patch will remove them, relying entirely on the
device semaphores provided by the driver core.
The code paths affected by this patch are:
device_add and device_del: The USB core already holds the parent
lock, so no actual change is needed.
driver_register and driver_unregister: The driver core will now
lock both the parent and the device before probing or removing.
driver_bind and driver_unbind (in sysfs): These routines will
now lock both the parent and the device before binding or
unbinding.
bus_rescan_devices: The helper routine will lock the parent
before probing a device.
I have not tested this patch for conflicts with other subsystems. As
far as I can see, the only possibility of conflict would lie in the
bus_rescan_devices pathway, and it seems pretty remote. Nevertheless,
it would be good for this to get a lot of testing in -mm.
Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2005-11-17 14:54:12 -07:00
|
|
|
if (!dev->driver) {
|
|
|
|
if (dev->parent) /* Needed for USB */
|
2010-02-17 11:57:05 -07:00
|
|
|
device_lock(dev->parent);
|
2006-08-14 23:43:20 -06:00
|
|
|
ret = device_attach(dev);
|
[PATCH] Hold the device's parent's lock during probe and remove
This patch (as604) makes the driver core hold a device's parent's lock
as well as the device's lock during calls to the probe and remove
methods in a driver. This facility is needed by USB device drivers,
owing to the peculiar way USB devices work:
A device provides multiple interfaces, and drivers are bound
to interfaces rather than to devices;
Nevertheless a reset, reset-configuration, suspend, or resume
affects the entire device and requires the caller to hold the
lock for the device, not just a lock for one of the interfaces.
Since a USB driver's probe method is always called with the interface
lock held, the locking order rules (always lock parent before child)
prevent these methods from acquiring the device lock. The solution
provided here is to call all probe and remove methods, for all devices
(not just USB), with the parent lock already acquired.
Although currently only the USB subsystem requires these changes, people
have mentioned in prior discussion that the overhead of acquiring an
extra semaphore in all the prove/remove sequences is not overly large.
Up to now, the USB core has been using its own set of private
semaphores. A followup patch will remove them, relying entirely on the
device semaphores provided by the driver core.
The code paths affected by this patch are:
device_add and device_del: The USB core already holds the parent
lock, so no actual change is needed.
driver_register and driver_unregister: The driver core will now
lock both the parent and the device before probing or removing.
driver_bind and driver_unbind (in sysfs): These routines will
now lock both the parent and the device before binding or
unbinding.
bus_rescan_devices: The helper routine will lock the parent
before probing a device.
I have not tested this patch for conflicts with other subsystems. As
far as I can see, the only possibility of conflict would lie in the
bus_rescan_devices pathway, and it seems pretty remote. Nevertheless,
it would be good for this to get a lot of testing in -mm.
Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2005-11-17 14:54:12 -07:00
|
|
|
if (dev->parent)
|
2010-02-17 11:57:05 -07:00
|
|
|
device_unlock(dev->parent);
|
[PATCH] Hold the device's parent's lock during probe and remove
This patch (as604) makes the driver core hold a device's parent's lock
as well as the device's lock during calls to the probe and remove
methods in a driver. This facility is needed by USB device drivers,
owing to the peculiar way USB devices work:
A device provides multiple interfaces, and drivers are bound
to interfaces rather than to devices;
Nevertheless a reset, reset-configuration, suspend, or resume
affects the entire device and requires the caller to hold the
lock for the device, not just a lock for one of the interfaces.
Since a USB driver's probe method is always called with the interface
lock held, the locking order rules (always lock parent before child)
prevent these methods from acquiring the device lock. The solution
provided here is to call all probe and remove methods, for all devices
(not just USB), with the parent lock already acquired.
Although currently only the USB subsystem requires these changes, people
have mentioned in prior discussion that the overhead of acquiring an
extra semaphore in all the prove/remove sequences is not overly large.
Up to now, the USB core has been using its own set of private
semaphores. A followup patch will remove them, relying entirely on the
device semaphores provided by the driver core.
The code paths affected by this patch are:
device_add and device_del: The USB core already holds the parent
lock, so no actual change is needed.
driver_register and driver_unregister: The driver core will now
lock both the parent and the device before probing or removing.
driver_bind and driver_unbind (in sysfs): These routines will
now lock both the parent and the device before binding or
unbinding.
bus_rescan_devices: The helper routine will lock the parent
before probing a device.
I have not tested this patch for conflicts with other subsystems. As
far as I can see, the only possibility of conflict would lie in the
bus_rescan_devices pathway, and it seems pretty remote. Nevertheless,
it would be good for this to get a lot of testing in -mm.
Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2005-11-17 14:54:12 -07:00
|
|
|
}
|
2006-08-14 23:43:20 -06:00
|
|
|
return ret < 0 ? ret : 0;
|
2005-04-16 16:20:36 -06:00
|
|
|
}
|
|
|
|
|
|
|
|
/**
|
2005-06-22 17:09:05 -06:00
|
|
|
* bus_rescan_devices - rescan devices on the bus for possible drivers
|
|
|
|
* @bus: the bus to scan.
|
2005-04-16 16:20:36 -06:00
|
|
|
*
|
2005-06-22 17:09:05 -06:00
|
|
|
* This function will look for devices on the bus with no driver
|
|
|
|
* attached and rescan it against existing drivers to see if it matches
|
|
|
|
* any by calling device_attach() for the unbound devices.
|
2005-04-16 16:20:36 -06:00
|
|
|
*/
|
2008-01-24 23:50:12 -07:00
|
|
|
int bus_rescan_devices(struct bus_type *bus)
|
2005-04-16 16:20:36 -06:00
|
|
|
{
|
2006-08-14 23:43:20 -06:00
|
|
|
return bus_for_each_dev(bus, NULL, NULL, bus_rescan_devices_helper);
|
2005-04-16 16:20:36 -06:00
|
|
|
}
|
2008-01-24 23:50:12 -07:00
|
|
|
EXPORT_SYMBOL_GPL(bus_rescan_devices);
|
2005-04-16 16:20:36 -06:00
|
|
|
|
2006-03-14 09:18:18 -07:00
|
|
|
/**
|
|
|
|
* device_reprobe - remove driver for a device and probe for a new driver
|
|
|
|
* @dev: the device to reprobe
|
|
|
|
*
|
|
|
|
* This function detaches the attached driver (if any) for the given
|
|
|
|
* device and restarts the driver probing process. It is intended
|
|
|
|
* to use if probing criteria changed during a devices lifetime and
|
|
|
|
* driver attachment should change accordingly.
|
|
|
|
*/
|
2006-08-14 23:43:20 -06:00
|
|
|
int device_reprobe(struct device *dev)
|
2006-03-14 09:18:18 -07:00
|
|
|
{
|
|
|
|
if (dev->driver) {
|
|
|
|
if (dev->parent) /* Needed for USB */
|
2010-02-17 11:57:05 -07:00
|
|
|
device_lock(dev->parent);
|
2006-03-14 09:18:18 -07:00
|
|
|
device_release_driver(dev);
|
|
|
|
if (dev->parent)
|
2010-02-17 11:57:05 -07:00
|
|
|
device_unlock(dev->parent);
|
2006-03-14 09:18:18 -07:00
|
|
|
}
|
2006-08-14 23:43:20 -06:00
|
|
|
return bus_rescan_devices_helper(dev, NULL);
|
2006-03-14 09:18:18 -07:00
|
|
|
}
|
|
|
|
EXPORT_SYMBOL_GPL(device_reprobe);
|
2005-04-16 16:20:36 -06:00
|
|
|
|
|
|
|
/**
|
2008-01-24 23:50:12 -07:00
|
|
|
* find_bus - locate bus by name.
|
|
|
|
* @name: name of bus.
|
2005-04-16 16:20:36 -06:00
|
|
|
*
|
2008-01-24 23:50:12 -07:00
|
|
|
* Call kset_find_obj() to iterate over list of buses to
|
|
|
|
* find a bus by name. Return bus if found.
|
2005-04-16 16:20:36 -06:00
|
|
|
*
|
2008-01-24 23:50:12 -07:00
|
|
|
* Note that kset_find_obj increments bus' reference count.
|
2005-04-16 16:20:36 -06:00
|
|
|
*/
|
2006-06-26 14:26:56 -06:00
|
|
|
#if 0
|
2008-01-24 23:50:12 -07:00
|
|
|
struct bus_type *find_bus(char *name)
|
2005-04-16 16:20:36 -06:00
|
|
|
{
|
2008-01-24 23:50:12 -07:00
|
|
|
struct kobject *k = kset_find_obj(bus_kset, name);
|
2005-04-16 16:20:36 -06:00
|
|
|
return k ? to_bus(k) : NULL;
|
|
|
|
}
|
2006-06-26 14:26:56 -06:00
|
|
|
#endif /* 0 */
|
2005-04-16 16:20:36 -06:00
|
|
|
|
2013-08-08 16:22:57 -06:00
|
|
|
static int bus_add_groups(struct bus_type *bus,
|
|
|
|
const struct attribute_group **groups)
|
|
|
|
{
|
2013-08-21 14:47:50 -06:00
|
|
|
return sysfs_create_groups(&bus->p->subsys.kobj, groups);
|
2013-08-08 16:22:57 -06:00
|
|
|
}
|
|
|
|
|
|
|
|
static void bus_remove_groups(struct bus_type *bus,
|
|
|
|
const struct attribute_group **groups)
|
|
|
|
{
|
2013-08-21 14:47:50 -06:00
|
|
|
sysfs_remove_groups(&bus->p->subsys.kobj, groups);
|
2013-08-08 16:22:57 -06:00
|
|
|
}
|
|
|
|
|
2005-09-06 17:56:51 -06:00
|
|
|
static void klist_devices_get(struct klist_node *n)
|
|
|
|
{
|
2008-12-16 13:26:21 -07:00
|
|
|
struct device_private *dev_prv = to_device_private_bus(n);
|
|
|
|
struct device *dev = dev_prv->device;
|
2005-09-06 17:56:51 -06:00
|
|
|
|
|
|
|
get_device(dev);
|
|
|
|
}
|
|
|
|
|
|
|
|
static void klist_devices_put(struct klist_node *n)
|
|
|
|
{
|
2008-12-16 13:26:21 -07:00
|
|
|
struct device_private *dev_prv = to_device_private_bus(n);
|
|
|
|
struct device *dev = dev_prv->device;
|
2005-09-06 17:56:51 -06:00
|
|
|
|
|
|
|
put_device(dev);
|
|
|
|
}
|
|
|
|
|
2007-08-12 12:43:55 -06:00
|
|
|
static ssize_t bus_uevent_store(struct bus_type *bus,
|
|
|
|
const char *buf, size_t count)
|
|
|
|
{
|
|
|
|
enum kobject_action action;
|
|
|
|
|
|
|
|
if (kobject_action_type(buf, count, &action) == 0)
|
2007-11-01 20:41:16 -06:00
|
|
|
kobject_uevent(&bus->p->subsys.kobj, action);
|
2007-08-12 12:43:55 -06:00
|
|
|
return count;
|
|
|
|
}
|
|
|
|
static BUS_ATTR(uevent, S_IWUSR, NULL, bus_uevent_store);
|
|
|
|
|
2005-04-16 16:20:36 -06:00
|
|
|
/**
|
2013-03-12 10:21:19 -06:00
|
|
|
* bus_register - register a driver-core subsystem
|
2012-01-21 12:02:28 -07:00
|
|
|
* @bus: bus to register
|
2005-04-16 16:20:36 -06:00
|
|
|
*
|
2012-01-21 12:02:28 -07:00
|
|
|
* Once we have that, we register the bus with the kobject
|
2008-01-24 23:50:12 -07:00
|
|
|
* infrastructure, then register the children subsystems it has:
|
2011-12-14 15:29:38 -07:00
|
|
|
* the devices and drivers that belong to the subsystem.
|
2005-04-16 16:20:36 -06:00
|
|
|
*/
|
2013-03-12 10:21:19 -06:00
|
|
|
int bus_register(struct bus_type *bus)
|
2005-04-16 16:20:36 -06:00
|
|
|
{
|
|
|
|
int retval;
|
2010-11-15 15:13:18 -07:00
|
|
|
struct subsys_private *priv;
|
2013-03-12 10:21:19 -06:00
|
|
|
struct lock_class_key *key = &bus->lock_key;
|
2007-11-01 20:41:16 -06:00
|
|
|
|
2010-11-15 15:13:18 -07:00
|
|
|
priv = kzalloc(sizeof(struct subsys_private), GFP_KERNEL);
|
2007-11-01 20:41:16 -06:00
|
|
|
if (!priv)
|
|
|
|
return -ENOMEM;
|
|
|
|
|
|
|
|
priv->bus = bus;
|
|
|
|
bus->p = priv;
|
2005-04-16 16:20:36 -06:00
|
|
|
|
2007-11-01 20:41:16 -06:00
|
|
|
BLOCKING_INIT_NOTIFIER_HEAD(&priv->bus_notifier);
|
Driver core: add notification of bus events
I finally did as you suggested and added the notifier to the struct
bus_type itself. There are still problems to be expected is something
attaches to a bus type where the code can hook in different struct
device sub-classes (which is imho a big bogosity but I won't even try to
argue that case now) but it will solve nicely a number of issues I've
had so far.
That also means that clients interested in registering for such
notifications have to do it before devices are added and after bus types
are registered. Fortunately, most bus types that matter for the various
usage scenarios I have in mind are registerd at postcore_initcall time,
which means I have a really nice spot at arch_initcall time to add my
notifiers.
There are 4 notifications provided. Device being added (before hooked to
the bus) and removed (failure of previous case or after being unhooked
from the bus), along with driver being bound to a device and about to be
unbound.
The usage I have for these are:
- The 2 first ones are used to maintain a struct device_ext that is
hooked to struct device.firmware_data. This structure contains for now a
pointer to the Open Firmware node related to the device (if any), the
NUMA node ID (for quick access to it) and the DMA operations pointers &
iommu table instance for DMA to/from this device. For bus types I own
(like IBM VIO or EBUS), I just maintain that structure directly from the
bus code when creating the devices. But for bus types managed by generic
code like PCI or platform (actually, of_platform which is a variation of
platform linked to Open Firmware device-tree), I need this notifier.
- The other two ones have a completely different usage scenario. I have
cases where multiple devices and their drivers depend on each other. For
example, the IBM EMAC network driver needs to attach to a MAL DMA engine
which is a separate device, and a PHY interface which is also a separate
device. They are all of_platform_device's (well, about to be with my
upcoming patches) but there is no say in what precise order the core
will "probe" them and instanciate the various modules. The solution I
found for that is to have the drivers for emac to use multithread_probe,
and wait for a driver to be bound to the target MAL and PHY control
devices (the device-tree contains reference to the MAL and PHY interface
nodes, which I can then match to of_platform_devices). Right now, I've
been polling, but with that notifier, I can more cleanly wait (with a
timeout of course).
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2006-10-24 21:44:59 -06:00
|
|
|
|
2007-11-01 20:41:16 -06:00
|
|
|
retval = kobject_set_name(&priv->subsys.kobj, "%s", bus->name);
|
2005-04-16 16:20:36 -06:00
|
|
|
if (retval)
|
|
|
|
goto out;
|
|
|
|
|
2007-11-01 20:41:16 -06:00
|
|
|
priv->subsys.kobj.kset = bus_kset;
|
|
|
|
priv->subsys.kobj.ktype = &bus_ktype;
|
|
|
|
priv->drivers_autoprobe = 1;
|
2007-09-12 16:06:57 -06:00
|
|
|
|
2007-11-01 20:41:16 -06:00
|
|
|
retval = kset_register(&priv->subsys);
|
2005-04-16 16:20:36 -06:00
|
|
|
if (retval)
|
|
|
|
goto out;
|
|
|
|
|
2007-08-12 12:43:55 -06:00
|
|
|
retval = bus_create_file(bus, &bus_attr_uevent);
|
|
|
|
if (retval)
|
|
|
|
goto bus_uevent_fail;
|
|
|
|
|
2007-11-01 20:41:16 -06:00
|
|
|
priv->devices_kset = kset_create_and_add("devices", NULL,
|
|
|
|
&priv->subsys.kobj);
|
|
|
|
if (!priv->devices_kset) {
|
2007-11-01 14:31:26 -06:00
|
|
|
retval = -ENOMEM;
|
2005-04-16 16:20:36 -06:00
|
|
|
goto bus_devices_fail;
|
2007-11-01 14:31:26 -06:00
|
|
|
}
|
2005-04-16 16:20:36 -06:00
|
|
|
|
2007-11-01 20:41:16 -06:00
|
|
|
priv->drivers_kset = kset_create_and_add("drivers", NULL,
|
|
|
|
&priv->subsys.kobj);
|
|
|
|
if (!priv->drivers_kset) {
|
2007-11-01 14:31:26 -06:00
|
|
|
retval = -ENOMEM;
|
2005-04-16 16:20:36 -06:00
|
|
|
goto bus_drivers_fail;
|
2007-11-01 14:31:26 -06:00
|
|
|
}
|
2005-03-21 12:49:14 -07:00
|
|
|
|
2011-12-14 15:29:38 -07:00
|
|
|
INIT_LIST_HEAD(&priv->interfaces);
|
|
|
|
__mutex_init(&priv->mutex, "subsys mutex", key);
|
2007-11-01 20:41:16 -06:00
|
|
|
klist_init(&priv->klist_devices, klist_devices_get, klist_devices_put);
|
|
|
|
klist_init(&priv->klist_drivers, NULL, NULL);
|
Driver core: udev triggered device-<>driver binding
We get two per-bus sysfs files:
ls-l /sys/subsystem/usb
drwxr-xr-x 2 root root 0 2007-02-16 16:42 devices
drwxr-xr-x 7 root root 0 2007-02-16 14:55 drivers
-rw-r--r-- 1 root root 4096 2007-02-16 16:42 drivers_autoprobe
--w------- 1 root root 4096 2007-02-16 16:42 drivers_probe
The flag "drivers_autoprobe" controls the behavior of the bus to bind
devices by default, or just initialize the device and leave it alone.
The command "drivers_probe" accepts a bus_id and the bus tries to bind a
driver to this device.
Systems who want to control the driver binding with udev, switch off the
bus initiated probing:
echo 0 > /sys/subsystem/usb/drivers_autoprobe
echo 0 > /sys/subsystem/pcmcia/drivers_autoprobe
...
and initiate the probing with udev rules like:
ACTION=="add", SUBSYSTEM=="usb", ATTR{subsystem/drivers_probe}="$kernel"
ACTION=="add", SUBSYSTEM=="pcmcia", ATTR{subsystem/drivers_probe}="$kernel"
...
Custom driver binding can happen in earlier rules by something like:
ACTION=="add", SUBSYSTEM=="usb", \
ATTRS{idVendor}=="1234", ATTRS{idProduct}=="5678" \
ATTR{subsystem/drivers/<custom-driver>/bind}="$kernel"
This is intended to solve the modprobe.conf mess with "install-rules", custom
bind/unbind-scripts and all the weird things people invented over the years.
It should also provide the functionality "libusual" was supposed to do.
With udev, one can just write a udev rule to drive all USB-disks at the
third port of USB-hub by the "ub" driver, and everything else by
usb-storage. One can also instruct udev to bind different wireless
drivers to identical cards - just selected by the pcmcia slot-number, and
whatever ...
To use the mentioned rules, it needs udev version 106, to be able to
write ATTR{}="$kernel" to sysfs files.
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2007-02-16 09:33:36 -07:00
|
|
|
|
|
|
|
retval = add_probe_files(bus);
|
|
|
|
if (retval)
|
|
|
|
goto bus_probe_files_fail;
|
|
|
|
|
2013-08-08 16:22:57 -06:00
|
|
|
retval = bus_add_groups(bus, bus->bus_groups);
|
|
|
|
if (retval)
|
|
|
|
goto bus_groups_fail;
|
2005-04-16 16:20:36 -06:00
|
|
|
|
2007-11-29 00:49:41 -07:00
|
|
|
pr_debug("bus: '%s': registered\n", bus->name);
|
2005-04-16 16:20:36 -06:00
|
|
|
return 0;
|
|
|
|
|
2013-08-08 16:22:57 -06:00
|
|
|
bus_groups_fail:
|
Driver core: udev triggered device-<>driver binding
We get two per-bus sysfs files:
ls-l /sys/subsystem/usb
drwxr-xr-x 2 root root 0 2007-02-16 16:42 devices
drwxr-xr-x 7 root root 0 2007-02-16 14:55 drivers
-rw-r--r-- 1 root root 4096 2007-02-16 16:42 drivers_autoprobe
--w------- 1 root root 4096 2007-02-16 16:42 drivers_probe
The flag "drivers_autoprobe" controls the behavior of the bus to bind
devices by default, or just initialize the device and leave it alone.
The command "drivers_probe" accepts a bus_id and the bus tries to bind a
driver to this device.
Systems who want to control the driver binding with udev, switch off the
bus initiated probing:
echo 0 > /sys/subsystem/usb/drivers_autoprobe
echo 0 > /sys/subsystem/pcmcia/drivers_autoprobe
...
and initiate the probing with udev rules like:
ACTION=="add", SUBSYSTEM=="usb", ATTR{subsystem/drivers_probe}="$kernel"
ACTION=="add", SUBSYSTEM=="pcmcia", ATTR{subsystem/drivers_probe}="$kernel"
...
Custom driver binding can happen in earlier rules by something like:
ACTION=="add", SUBSYSTEM=="usb", \
ATTRS{idVendor}=="1234", ATTRS{idProduct}=="5678" \
ATTR{subsystem/drivers/<custom-driver>/bind}="$kernel"
This is intended to solve the modprobe.conf mess with "install-rules", custom
bind/unbind-scripts and all the weird things people invented over the years.
It should also provide the functionality "libusual" was supposed to do.
With udev, one can just write a udev rule to drive all USB-disks at the
third port of USB-hub by the "ub" driver, and everything else by
usb-storage. One can also instruct udev to bind different wireless
drivers to identical cards - just selected by the pcmcia slot-number, and
whatever ...
To use the mentioned rules, it needs udev version 106, to be able to
write ATTR{}="$kernel" to sysfs files.
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2007-02-16 09:33:36 -07:00
|
|
|
remove_probe_files(bus);
|
|
|
|
bus_probe_files_fail:
|
2007-11-01 20:41:16 -06:00
|
|
|
kset_unregister(bus->p->drivers_kset);
|
2005-04-16 16:20:36 -06:00
|
|
|
bus_drivers_fail:
|
2007-11-01 20:41:16 -06:00
|
|
|
kset_unregister(bus->p->devices_kset);
|
2005-04-16 16:20:36 -06:00
|
|
|
bus_devices_fail:
|
2007-08-12 12:43:55 -06:00
|
|
|
bus_remove_file(bus, &bus_attr_uevent);
|
|
|
|
bus_uevent_fail:
|
2007-11-01 20:41:16 -06:00
|
|
|
kset_unregister(&bus->p->subsys);
|
2005-04-16 16:20:36 -06:00
|
|
|
out:
|
2010-07-15 03:43:54 -06:00
|
|
|
kfree(bus->p);
|
2009-02-14 06:23:22 -07:00
|
|
|
bus->p = NULL;
|
2005-04-16 16:20:36 -06:00
|
|
|
return retval;
|
|
|
|
}
|
2013-03-12 10:21:19 -06:00
|
|
|
EXPORT_SYMBOL_GPL(bus_register);
|
2005-04-16 16:20:36 -06:00
|
|
|
|
|
|
|
/**
|
2008-01-24 23:50:12 -07:00
|
|
|
* bus_unregister - remove a bus from the system
|
|
|
|
* @bus: bus.
|
2005-04-16 16:20:36 -06:00
|
|
|
*
|
2008-01-24 23:50:12 -07:00
|
|
|
* Unregister the child subsystems and the bus itself.
|
|
|
|
* Finally, we call bus_put() to release the refcount
|
2005-04-16 16:20:36 -06:00
|
|
|
*/
|
2008-01-24 23:50:12 -07:00
|
|
|
void bus_unregister(struct bus_type *bus)
|
2005-04-16 16:20:36 -06:00
|
|
|
{
|
2007-11-29 00:49:41 -07:00
|
|
|
pr_debug("bus: '%s': unregistering\n", bus->name);
|
2011-12-14 15:29:38 -07:00
|
|
|
if (bus->dev_root)
|
|
|
|
device_unregister(bus->dev_root);
|
2013-08-08 16:22:57 -06:00
|
|
|
bus_remove_groups(bus, bus->bus_groups);
|
Driver core: udev triggered device-<>driver binding
We get two per-bus sysfs files:
ls-l /sys/subsystem/usb
drwxr-xr-x 2 root root 0 2007-02-16 16:42 devices
drwxr-xr-x 7 root root 0 2007-02-16 14:55 drivers
-rw-r--r-- 1 root root 4096 2007-02-16 16:42 drivers_autoprobe
--w------- 1 root root 4096 2007-02-16 16:42 drivers_probe
The flag "drivers_autoprobe" controls the behavior of the bus to bind
devices by default, or just initialize the device and leave it alone.
The command "drivers_probe" accepts a bus_id and the bus tries to bind a
driver to this device.
Systems who want to control the driver binding with udev, switch off the
bus initiated probing:
echo 0 > /sys/subsystem/usb/drivers_autoprobe
echo 0 > /sys/subsystem/pcmcia/drivers_autoprobe
...
and initiate the probing with udev rules like:
ACTION=="add", SUBSYSTEM=="usb", ATTR{subsystem/drivers_probe}="$kernel"
ACTION=="add", SUBSYSTEM=="pcmcia", ATTR{subsystem/drivers_probe}="$kernel"
...
Custom driver binding can happen in earlier rules by something like:
ACTION=="add", SUBSYSTEM=="usb", \
ATTRS{idVendor}=="1234", ATTRS{idProduct}=="5678" \
ATTR{subsystem/drivers/<custom-driver>/bind}="$kernel"
This is intended to solve the modprobe.conf mess with "install-rules", custom
bind/unbind-scripts and all the weird things people invented over the years.
It should also provide the functionality "libusual" was supposed to do.
With udev, one can just write a udev rule to drive all USB-disks at the
third port of USB-hub by the "ub" driver, and everything else by
usb-storage. One can also instruct udev to bind different wireless
drivers to identical cards - just selected by the pcmcia slot-number, and
whatever ...
To use the mentioned rules, it needs udev version 106, to be able to
write ATTR{}="$kernel" to sysfs files.
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2007-02-16 09:33:36 -07:00
|
|
|
remove_probe_files(bus);
|
2007-11-01 20:41:16 -06:00
|
|
|
kset_unregister(bus->p->drivers_kset);
|
|
|
|
kset_unregister(bus->p->devices_kset);
|
2007-08-12 12:43:55 -06:00
|
|
|
bus_remove_file(bus, &bus_attr_uevent);
|
2007-11-01 20:41:16 -06:00
|
|
|
kset_unregister(&bus->p->subsys);
|
2005-04-16 16:20:36 -06:00
|
|
|
}
|
2008-01-24 23:50:12 -07:00
|
|
|
EXPORT_SYMBOL_GPL(bus_unregister);
|
2005-04-16 16:20:36 -06:00
|
|
|
|
Driver core: add notification of bus events
I finally did as you suggested and added the notifier to the struct
bus_type itself. There are still problems to be expected is something
attaches to a bus type where the code can hook in different struct
device sub-classes (which is imho a big bogosity but I won't even try to
argue that case now) but it will solve nicely a number of issues I've
had so far.
That also means that clients interested in registering for such
notifications have to do it before devices are added and after bus types
are registered. Fortunately, most bus types that matter for the various
usage scenarios I have in mind are registerd at postcore_initcall time,
which means I have a really nice spot at arch_initcall time to add my
notifiers.
There are 4 notifications provided. Device being added (before hooked to
the bus) and removed (failure of previous case or after being unhooked
from the bus), along with driver being bound to a device and about to be
unbound.
The usage I have for these are:
- The 2 first ones are used to maintain a struct device_ext that is
hooked to struct device.firmware_data. This structure contains for now a
pointer to the Open Firmware node related to the device (if any), the
NUMA node ID (for quick access to it) and the DMA operations pointers &
iommu table instance for DMA to/from this device. For bus types I own
(like IBM VIO or EBUS), I just maintain that structure directly from the
bus code when creating the devices. But for bus types managed by generic
code like PCI or platform (actually, of_platform which is a variation of
platform linked to Open Firmware device-tree), I need this notifier.
- The other two ones have a completely different usage scenario. I have
cases where multiple devices and their drivers depend on each other. For
example, the IBM EMAC network driver needs to attach to a MAL DMA engine
which is a separate device, and a PHY interface which is also a separate
device. They are all of_platform_device's (well, about to be with my
upcoming patches) but there is no say in what precise order the core
will "probe" them and instanciate the various modules. The solution I
found for that is to have the drivers for emac to use multithread_probe,
and wait for a driver to be bound to the target MAL and PHY control
devices (the device-tree contains reference to the MAL and PHY interface
nodes, which I can then match to of_platform_devices). Right now, I've
been polling, but with that notifier, I can more cleanly wait (with a
timeout of course).
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2006-10-24 21:44:59 -06:00
|
|
|
int bus_register_notifier(struct bus_type *bus, struct notifier_block *nb)
|
|
|
|
{
|
2007-11-01 20:41:16 -06:00
|
|
|
return blocking_notifier_chain_register(&bus->p->bus_notifier, nb);
|
Driver core: add notification of bus events
I finally did as you suggested and added the notifier to the struct
bus_type itself. There are still problems to be expected is something
attaches to a bus type where the code can hook in different struct
device sub-classes (which is imho a big bogosity but I won't even try to
argue that case now) but it will solve nicely a number of issues I've
had so far.
That also means that clients interested in registering for such
notifications have to do it before devices are added and after bus types
are registered. Fortunately, most bus types that matter for the various
usage scenarios I have in mind are registerd at postcore_initcall time,
which means I have a really nice spot at arch_initcall time to add my
notifiers.
There are 4 notifications provided. Device being added (before hooked to
the bus) and removed (failure of previous case or after being unhooked
from the bus), along with driver being bound to a device and about to be
unbound.
The usage I have for these are:
- The 2 first ones are used to maintain a struct device_ext that is
hooked to struct device.firmware_data. This structure contains for now a
pointer to the Open Firmware node related to the device (if any), the
NUMA node ID (for quick access to it) and the DMA operations pointers &
iommu table instance for DMA to/from this device. For bus types I own
(like IBM VIO or EBUS), I just maintain that structure directly from the
bus code when creating the devices. But for bus types managed by generic
code like PCI or platform (actually, of_platform which is a variation of
platform linked to Open Firmware device-tree), I need this notifier.
- The other two ones have a completely different usage scenario. I have
cases where multiple devices and their drivers depend on each other. For
example, the IBM EMAC network driver needs to attach to a MAL DMA engine
which is a separate device, and a PHY interface which is also a separate
device. They are all of_platform_device's (well, about to be with my
upcoming patches) but there is no say in what precise order the core
will "probe" them and instanciate the various modules. The solution I
found for that is to have the drivers for emac to use multithread_probe,
and wait for a driver to be bound to the target MAL and PHY control
devices (the device-tree contains reference to the MAL and PHY interface
nodes, which I can then match to of_platform_devices). Right now, I've
been polling, but with that notifier, I can more cleanly wait (with a
timeout of course).
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2006-10-24 21:44:59 -06:00
|
|
|
}
|
|
|
|
EXPORT_SYMBOL_GPL(bus_register_notifier);
|
|
|
|
|
|
|
|
int bus_unregister_notifier(struct bus_type *bus, struct notifier_block *nb)
|
|
|
|
{
|
2007-11-01 20:41:16 -06:00
|
|
|
return blocking_notifier_chain_unregister(&bus->p->bus_notifier, nb);
|
Driver core: add notification of bus events
I finally did as you suggested and added the notifier to the struct
bus_type itself. There are still problems to be expected is something
attaches to a bus type where the code can hook in different struct
device sub-classes (which is imho a big bogosity but I won't even try to
argue that case now) but it will solve nicely a number of issues I've
had so far.
That also means that clients interested in registering for such
notifications have to do it before devices are added and after bus types
are registered. Fortunately, most bus types that matter for the various
usage scenarios I have in mind are registerd at postcore_initcall time,
which means I have a really nice spot at arch_initcall time to add my
notifiers.
There are 4 notifications provided. Device being added (before hooked to
the bus) and removed (failure of previous case or after being unhooked
from the bus), along with driver being bound to a device and about to be
unbound.
The usage I have for these are:
- The 2 first ones are used to maintain a struct device_ext that is
hooked to struct device.firmware_data. This structure contains for now a
pointer to the Open Firmware node related to the device (if any), the
NUMA node ID (for quick access to it) and the DMA operations pointers &
iommu table instance for DMA to/from this device. For bus types I own
(like IBM VIO or EBUS), I just maintain that structure directly from the
bus code when creating the devices. But for bus types managed by generic
code like PCI or platform (actually, of_platform which is a variation of
platform linked to Open Firmware device-tree), I need this notifier.
- The other two ones have a completely different usage scenario. I have
cases where multiple devices and their drivers depend on each other. For
example, the IBM EMAC network driver needs to attach to a MAL DMA engine
which is a separate device, and a PHY interface which is also a separate
device. They are all of_platform_device's (well, about to be with my
upcoming patches) but there is no say in what precise order the core
will "probe" them and instanciate the various modules. The solution I
found for that is to have the drivers for emac to use multithread_probe,
and wait for a driver to be bound to the target MAL and PHY control
devices (the device-tree contains reference to the MAL and PHY interface
nodes, which I can then match to of_platform_devices). Right now, I've
been polling, but with that notifier, I can more cleanly wait (with a
timeout of course).
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2006-10-24 21:44:59 -06:00
|
|
|
}
|
|
|
|
EXPORT_SYMBOL_GPL(bus_unregister_notifier);
|
|
|
|
|
2007-11-01 20:41:16 -06:00
|
|
|
struct kset *bus_get_kset(struct bus_type *bus)
|
|
|
|
{
|
2007-11-01 20:41:16 -06:00
|
|
|
return &bus->p->subsys;
|
2007-11-01 20:41:16 -06:00
|
|
|
}
|
|
|
|
EXPORT_SYMBOL_GPL(bus_get_kset);
|
|
|
|
|
2007-11-01 20:41:16 -06:00
|
|
|
struct klist *bus_get_device_klist(struct bus_type *bus)
|
|
|
|
{
|
2007-11-01 20:41:16 -06:00
|
|
|
return &bus->p->klist_devices;
|
2007-11-01 20:41:16 -06:00
|
|
|
}
|
|
|
|
EXPORT_SYMBOL_GPL(bus_get_device_klist);
|
|
|
|
|
2008-08-26 10:00:57 -06:00
|
|
|
/*
|
2010-11-21 06:15:01 -07:00
|
|
|
* Yes, this forcibly breaks the klist abstraction temporarily. It
|
2008-08-26 10:00:57 -06:00
|
|
|
* just wants to sort the klist, not change reference counts and
|
|
|
|
* take/drop locks rapidly in the process. It does all this while
|
|
|
|
* holding the lock for the list, so objects can't otherwise be
|
|
|
|
* added/removed while we're swizzling.
|
|
|
|
*/
|
|
|
|
static void device_insertion_sort_klist(struct device *a, struct list_head *list,
|
|
|
|
int (*compare)(const struct device *a,
|
|
|
|
const struct device *b))
|
|
|
|
{
|
|
|
|
struct list_head *pos;
|
|
|
|
struct klist_node *n;
|
2008-12-16 13:26:21 -07:00
|
|
|
struct device_private *dev_prv;
|
2008-08-26 10:00:57 -06:00
|
|
|
struct device *b;
|
|
|
|
|
|
|
|
list_for_each(pos, list) {
|
|
|
|
n = container_of(pos, struct klist_node, n_node);
|
2008-12-16 13:26:21 -07:00
|
|
|
dev_prv = to_device_private_bus(n);
|
|
|
|
b = dev_prv->device;
|
2008-08-26 10:00:57 -06:00
|
|
|
if (compare(a, b) <= 0) {
|
2008-12-16 13:26:21 -07:00
|
|
|
list_move_tail(&a->p->knode_bus.n_node,
|
|
|
|
&b->p->knode_bus.n_node);
|
2008-08-26 10:00:57 -06:00
|
|
|
return;
|
|
|
|
}
|
|
|
|
}
|
2008-12-16 13:26:21 -07:00
|
|
|
list_move_tail(&a->p->knode_bus.n_node, list);
|
2008-08-26 10:00:57 -06:00
|
|
|
}
|
|
|
|
|
|
|
|
void bus_sort_breadthfirst(struct bus_type *bus,
|
|
|
|
int (*compare)(const struct device *a,
|
|
|
|
const struct device *b))
|
|
|
|
{
|
|
|
|
LIST_HEAD(sorted_devices);
|
|
|
|
struct list_head *pos, *tmp;
|
|
|
|
struct klist_node *n;
|
2008-12-16 13:26:21 -07:00
|
|
|
struct device_private *dev_prv;
|
2008-08-26 10:00:57 -06:00
|
|
|
struct device *dev;
|
|
|
|
struct klist *device_klist;
|
|
|
|
|
|
|
|
device_klist = bus_get_device_klist(bus);
|
|
|
|
|
|
|
|
spin_lock(&device_klist->k_lock);
|
|
|
|
list_for_each_safe(pos, tmp, &device_klist->k_list) {
|
|
|
|
n = container_of(pos, struct klist_node, n_node);
|
2008-12-16 13:26:21 -07:00
|
|
|
dev_prv = to_device_private_bus(n);
|
|
|
|
dev = dev_prv->device;
|
2008-08-26 10:00:57 -06:00
|
|
|
device_insertion_sort_klist(dev, &sorted_devices, compare);
|
|
|
|
}
|
|
|
|
list_splice(&sorted_devices, &device_klist->k_list);
|
|
|
|
spin_unlock(&device_klist->k_lock);
|
|
|
|
}
|
|
|
|
EXPORT_SYMBOL_GPL(bus_sort_breadthfirst);
|
|
|
|
|
2011-12-14 15:29:38 -07:00
|
|
|
/**
|
|
|
|
* subsys_dev_iter_init - initialize subsys device iterator
|
|
|
|
* @iter: subsys iterator to initialize
|
|
|
|
* @subsys: the subsys we wanna iterate over
|
|
|
|
* @start: the device to start iterating from, if any
|
|
|
|
* @type: device_type of the devices to iterate over, NULL for all
|
|
|
|
*
|
|
|
|
* Initialize subsys iterator @iter such that it iterates over devices
|
|
|
|
* of @subsys. If @start is set, the list iteration will start there,
|
|
|
|
* otherwise if it is NULL, the iteration starts at the beginning of
|
|
|
|
* the list.
|
|
|
|
*/
|
2012-04-19 20:17:30 -06:00
|
|
|
void subsys_dev_iter_init(struct subsys_dev_iter *iter, struct bus_type *subsys,
|
|
|
|
struct device *start, const struct device_type *type)
|
2011-12-14 15:29:38 -07:00
|
|
|
{
|
|
|
|
struct klist_node *start_knode = NULL;
|
|
|
|
|
|
|
|
if (start)
|
|
|
|
start_knode = &start->p->knode_bus;
|
2012-04-19 20:17:30 -06:00
|
|
|
klist_iter_init_node(&subsys->p->klist_devices, &iter->ki, start_knode);
|
|
|
|
iter->type = type;
|
2011-12-14 15:29:38 -07:00
|
|
|
}
|
|
|
|
EXPORT_SYMBOL_GPL(subsys_dev_iter_init);
|
|
|
|
|
|
|
|
/**
|
|
|
|
* subsys_dev_iter_next - iterate to the next device
|
|
|
|
* @iter: subsys iterator to proceed
|
|
|
|
*
|
|
|
|
* Proceed @iter to the next device and return it. Returns NULL if
|
|
|
|
* iteration is complete.
|
|
|
|
*
|
|
|
|
* The returned device is referenced and won't be released till
|
|
|
|
* iterator is proceed to the next device or exited. The caller is
|
|
|
|
* free to do whatever it wants to do with the device including
|
|
|
|
* calling back into subsys code.
|
|
|
|
*/
|
|
|
|
struct device *subsys_dev_iter_next(struct subsys_dev_iter *iter)
|
|
|
|
{
|
|
|
|
struct klist_node *knode;
|
|
|
|
struct device *dev;
|
|
|
|
|
|
|
|
for (;;) {
|
|
|
|
knode = klist_next(&iter->ki);
|
|
|
|
if (!knode)
|
|
|
|
return NULL;
|
|
|
|
dev = container_of(knode, struct device_private, knode_bus)->device;
|
|
|
|
if (!iter->type || iter->type == dev->type)
|
|
|
|
return dev;
|
|
|
|
}
|
|
|
|
}
|
|
|
|
EXPORT_SYMBOL_GPL(subsys_dev_iter_next);
|
|
|
|
|
|
|
|
/**
|
|
|
|
* subsys_dev_iter_exit - finish iteration
|
|
|
|
* @iter: subsys iterator to finish
|
|
|
|
*
|
|
|
|
* Finish an iteration. Always call this function after iteration is
|
|
|
|
* complete whether the iteration ran till the end or not.
|
|
|
|
*/
|
|
|
|
void subsys_dev_iter_exit(struct subsys_dev_iter *iter)
|
|
|
|
{
|
|
|
|
klist_iter_exit(&iter->ki);
|
|
|
|
}
|
|
|
|
EXPORT_SYMBOL_GPL(subsys_dev_iter_exit);
|
|
|
|
|
|
|
|
int subsys_interface_register(struct subsys_interface *sif)
|
|
|
|
{
|
|
|
|
struct bus_type *subsys;
|
|
|
|
struct subsys_dev_iter iter;
|
|
|
|
struct device *dev;
|
|
|
|
|
|
|
|
if (!sif || !sif->subsys)
|
|
|
|
return -ENODEV;
|
|
|
|
|
|
|
|
subsys = bus_get(sif->subsys);
|
|
|
|
if (!subsys)
|
|
|
|
return -EINVAL;
|
|
|
|
|
|
|
|
mutex_lock(&subsys->p->mutex);
|
|
|
|
list_add_tail(&sif->node, &subsys->p->interfaces);
|
|
|
|
if (sif->add_dev) {
|
|
|
|
subsys_dev_iter_init(&iter, subsys, NULL, NULL);
|
|
|
|
while ((dev = subsys_dev_iter_next(&iter)))
|
|
|
|
sif->add_dev(dev, sif);
|
|
|
|
subsys_dev_iter_exit(&iter);
|
|
|
|
}
|
|
|
|
mutex_unlock(&subsys->p->mutex);
|
|
|
|
|
|
|
|
return 0;
|
|
|
|
}
|
|
|
|
EXPORT_SYMBOL_GPL(subsys_interface_register);
|
|
|
|
|
|
|
|
void subsys_interface_unregister(struct subsys_interface *sif)
|
|
|
|
{
|
2012-01-13 19:06:03 -07:00
|
|
|
struct bus_type *subsys;
|
2011-12-14 15:29:38 -07:00
|
|
|
struct subsys_dev_iter iter;
|
|
|
|
struct device *dev;
|
|
|
|
|
2012-01-13 19:06:03 -07:00
|
|
|
if (!sif || !sif->subsys)
|
2011-12-14 15:29:38 -07:00
|
|
|
return;
|
|
|
|
|
2012-01-13 19:06:03 -07:00
|
|
|
subsys = sif->subsys;
|
|
|
|
|
2011-12-14 15:29:38 -07:00
|
|
|
mutex_lock(&subsys->p->mutex);
|
|
|
|
list_del_init(&sif->node);
|
|
|
|
if (sif->remove_dev) {
|
|
|
|
subsys_dev_iter_init(&iter, subsys, NULL, NULL);
|
|
|
|
while ((dev = subsys_dev_iter_next(&iter)))
|
|
|
|
sif->remove_dev(dev, sif);
|
|
|
|
subsys_dev_iter_exit(&iter);
|
|
|
|
}
|
|
|
|
mutex_unlock(&subsys->p->mutex);
|
|
|
|
|
|
|
|
bus_put(subsys);
|
|
|
|
}
|
|
|
|
EXPORT_SYMBOL_GPL(subsys_interface_unregister);
|
|
|
|
|
|
|
|
static void system_root_device_release(struct device *dev)
|
|
|
|
{
|
|
|
|
kfree(dev);
|
|
|
|
}
|
2013-03-12 12:30:05 -06:00
|
|
|
|
|
|
|
static int subsys_register(struct bus_type *subsys,
|
|
|
|
const struct attribute_group **groups,
|
|
|
|
struct kobject *parent_of_root)
|
2011-12-14 15:29:38 -07:00
|
|
|
{
|
|
|
|
struct device *dev;
|
|
|
|
int err;
|
|
|
|
|
|
|
|
err = bus_register(subsys);
|
|
|
|
if (err < 0)
|
|
|
|
return err;
|
|
|
|
|
|
|
|
dev = kzalloc(sizeof(struct device), GFP_KERNEL);
|
|
|
|
if (!dev) {
|
|
|
|
err = -ENOMEM;
|
|
|
|
goto err_dev;
|
|
|
|
}
|
|
|
|
|
|
|
|
err = dev_set_name(dev, "%s", subsys->name);
|
|
|
|
if (err < 0)
|
|
|
|
goto err_name;
|
|
|
|
|
2013-03-12 12:30:05 -06:00
|
|
|
dev->kobj.parent = parent_of_root;
|
2011-12-14 15:29:38 -07:00
|
|
|
dev->groups = groups;
|
|
|
|
dev->release = system_root_device_release;
|
|
|
|
|
|
|
|
err = device_register(dev);
|
|
|
|
if (err < 0)
|
|
|
|
goto err_dev_reg;
|
|
|
|
|
|
|
|
subsys->dev_root = dev;
|
|
|
|
return 0;
|
|
|
|
|
|
|
|
err_dev_reg:
|
|
|
|
put_device(dev);
|
|
|
|
dev = NULL;
|
|
|
|
err_name:
|
|
|
|
kfree(dev);
|
|
|
|
err_dev:
|
|
|
|
bus_unregister(subsys);
|
|
|
|
return err;
|
|
|
|
}
|
2013-03-12 12:30:05 -06:00
|
|
|
|
|
|
|
/**
|
|
|
|
* subsys_system_register - register a subsystem at /sys/devices/system/
|
|
|
|
* @subsys: system subsystem
|
|
|
|
* @groups: default attributes for the root device
|
|
|
|
*
|
|
|
|
* All 'system' subsystems have a /sys/devices/system/<name> root device
|
|
|
|
* with the name of the subsystem. The root device can carry subsystem-
|
|
|
|
* wide attributes. All registered devices are below this single root
|
|
|
|
* device and are named after the subsystem with a simple enumeration
|
2014-02-18 06:54:36 -07:00
|
|
|
* number appended. The registered devices are not explicitly named;
|
2013-03-12 12:30:05 -06:00
|
|
|
* only 'id' in the device needs to be set.
|
|
|
|
*
|
|
|
|
* Do not use this interface for anything new, it exists for compatibility
|
|
|
|
* with bad ideas only. New subsystems should use plain subsystems; and
|
|
|
|
* add the subsystem-wide attributes should be added to the subsystem
|
|
|
|
* directory itself and not some create fake root-device placed in
|
|
|
|
* /sys/devices/system/<name>.
|
|
|
|
*/
|
|
|
|
int subsys_system_register(struct bus_type *subsys,
|
|
|
|
const struct attribute_group **groups)
|
|
|
|
{
|
|
|
|
return subsys_register(subsys, groups, &system_kset->kobj);
|
|
|
|
}
|
2011-12-14 15:29:38 -07:00
|
|
|
EXPORT_SYMBOL_GPL(subsys_system_register);
|
|
|
|
|
2013-03-12 12:30:05 -06:00
|
|
|
/**
|
|
|
|
* subsys_virtual_register - register a subsystem at /sys/devices/virtual/
|
|
|
|
* @subsys: virtual subsystem
|
|
|
|
* @groups: default attributes for the root device
|
|
|
|
*
|
|
|
|
* All 'virtual' subsystems have a /sys/devices/system/<name> root device
|
|
|
|
* with the name of the subystem. The root device can carry subsystem-wide
|
|
|
|
* attributes. All registered devices are below this single root device.
|
|
|
|
* There's no restriction on device naming. This is for kernel software
|
|
|
|
* constructs which need sysfs interface.
|
|
|
|
*/
|
|
|
|
int subsys_virtual_register(struct bus_type *subsys,
|
|
|
|
const struct attribute_group **groups)
|
|
|
|
{
|
|
|
|
struct kobject *virtual_dir;
|
|
|
|
|
|
|
|
virtual_dir = virtual_device_parent(NULL);
|
|
|
|
if (!virtual_dir)
|
|
|
|
return -ENOMEM;
|
|
|
|
|
|
|
|
return subsys_register(subsys, groups, virtual_dir);
|
|
|
|
}
|
2013-05-10 10:14:04 -06:00
|
|
|
EXPORT_SYMBOL_GPL(subsys_virtual_register);
|
2013-03-12 12:30:05 -06:00
|
|
|
|
2005-04-16 16:20:36 -06:00
|
|
|
int __init buses_init(void)
|
|
|
|
{
|
2007-10-29 22:22:26 -06:00
|
|
|
bus_kset = kset_create_and_add("bus", &bus_uevent_ops, NULL);
|
|
|
|
if (!bus_kset)
|
|
|
|
return -ENOMEM;
|
2011-12-14 15:29:38 -07:00
|
|
|
|
|
|
|
system_kset = kset_create_and_add("system", NULL, &devices_kset->kobj);
|
|
|
|
if (!system_kset)
|
|
|
|
return -ENOMEM;
|
|
|
|
|
2007-10-29 22:22:26 -06:00
|
|
|
return 0;
|
2005-04-16 16:20:36 -06:00
|
|
|
}
|