![Linus Torvalds](/assets/img/avatar_default.png)
- ACPICA update to upstream revision 20150818 including method tracing extensions to allow more in-depth AML debugging in the kernel and a number of assorted fixes and cleanups (Bob Moore, Lv Zheng, Markus Elfring). - ACPI sysfs code updates and a documentation update related to AML method tracing (Lv Zheng). - ACPI EC driver fix related to serialized evaluations of _Qxx methods and ACPI tools updates allowing the EC userspace tool to be built from the kernel source (Lv Zheng). - ACPI processor driver updates preparing it for future introduction of CPPC support and ACPI PCC mailbox driver updates (Ashwin Chaugule). - ACPI interrupts enumeration fix for a regression related to the handling of IRQ attribute conflicts between MADT and the ACPI namespace (Jiang Liu). - Fixes related to ACPI device PM (Mika Westerberg, Srinidhi Kasagar). - ACPI device registration code reorganization to separate the sysfs-related code and bus type operations from the rest (Rafael J Wysocki). - Assorted cleanups in the ACPI core (Jarkko Nikula, Mathias Krause, Andy Shevchenko, Rafael J Wysocki, Nicolas Iooss). - ACPI cpufreq driver and ia64 cpufreq driver fixes and cleanups (Pan Xinhui, Rafael J Wysocki). - cpufreq core cleanups on top of the previous changes allowing it to preseve its sysfs directories over system suspend/resume (Viresh Kumar, Rafael J Wysocki, Sebastian Andrzej Siewior). - cpufreq fixes and cleanups related to governors (Viresh Kumar). - cpufreq updates (core and the cpufreq-dt driver) related to the turbo/boost mode support (Viresh Kumar, Bartlomiej Zolnierkiewicz). - New DT bindings for Operating Performance Points (OPP), support for them in the OPP framework and in the cpufreq-dt driver plus related OPP framework fixes and cleanups (Viresh Kumar). - cpufreq powernv driver updates (Shilpasri G Bhat). - New cpufreq driver for Mediatek MT8173 (Pi-Cheng Chen). - Assorted cpufreq driver (speedstep-lib, sfi, integrator) cleanups and fixes (Abhilash Jindal, Andrzej Hajda, Cristian Ardelean). - intel_pstate driver updates including Skylake-S support, support for enabling HW P-states per CPU and an additional vendor bypass list entry (Kristen Carlson Accardi, Chen Yu, Ethan Zhao). - cpuidle core fixes related to the handling of coupled idle states (Xunlei Pang). - intel_idle driver updates including Skylake Client support and support for freeze-mode-specific idle states (Len Brown). - Driver core updates related to power management (Andy Shevchenko, Rafael J Wysocki). - Generic power domains framework fixes and cleanups (Jon Hunter, Geert Uytterhoeven, Rajendra Nayak, Ulf Hansson). - Device PM QoS framework update to allow the latency tolerance setting to be exposed to user space via sysfs (Mika Westerberg). - devfreq support for PPMUv2 in Exynos5433 and a fix for an incorrect exynos-ppmu DT binding (Chanwoo Choi, Javier Martinez Canillas). - System sleep support updates (Alan Stern, Len Brown, SungEun Kim). - rockchip-io AVS support updates (Heiko Stuebner). - PM core clocks support fixup (Colin Ian King). - Power capping RAPL driver update including support for Skylake H/S and Broadwell-H (Radivoje Jovanovic, Seiichi Ikarashi). - Generic device properties framework fixes related to the handling of static (driver-provided) property sets (Andy Shevchenko). - turbostat and cpupower updates (Len Brown, Shilpasri G Bhat, Shreyas B Prabhu). / -----BEGIN PGP SIGNATURE----- Version: GnuPG v2.0.22 (GNU/Linux) iQIcBAABCAAGBQJV5hhGAAoJEILEb/54YlRxs+EQAK51iFk48+IbpHYaZZ50Yo4m ZZc2zBcbwRcBlU9vKERrhG+jieSl8J/JJNxT8vBjKqyvNw038mCjewQh02ol0HuC R7nlDiVJkmZ50sLO4xwE/1UBZr/XqbddwCUnYzvFMkMTA0ePzFtf8BrJ1FXpT8S/ fkwSXQty6hvJDwxkfrbMSaA730wMju9lahx8D6MlmUAedWYZOJDMQKB4WKa/St5X 9uckBPHUBB2KiKlXxdbFPwKLNxHvLROq5SpDLc6cM/7XZB+QfNFy85CUjCUtYo1O 1W8k0qnztvZ6UEv27qz5dejGyAGOarMWGGNsmL9evoeGeHRpQL+dom7HcTnbAfUZ walyhYSm/zKkdy7Vl3xWUUQkMG48+PviMI6K0YhHXb3Rm5wlR/yBNZTwNIty9SX/ fKCHEa8QynWwLxgm53c3xRkiitJxMsHNK03moLD9zQMjshTyTNvpNbZoahyKQzk6 H+9M1DBRHhkkREDWSwGutukxfEMtWe2vcZcyERrFiY7l5k1j58DwDBMPqjPhRv6q P/1NlCzr0XYf83Y86J18LbDuPGDhTjjIEn6CqbtI2mmWqTg3+rF7zvS2ux+FzMnA gisv8l6GT9JiWhxKFqqL/rrVpwtyHebWLYE/RpNUW6fEzLziRNj1qyYO9dqI/GGi I3rfxlXoc/5xJWCgNB8f =fTgI -----END PGP SIGNATURE----- Merge tag 'pm+acpi-4.3-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm Pull power management and ACPI updates from Rafael Wysocki: "From the number of commits perspective, the biggest items are ACPICA and cpufreq changes with the latter taking the lead (over 50 commits). On the cpufreq front, there are many cleanups and minor fixes in the core and governors, driver updates etc. We also have a new cpufreq driver for Mediatek MT8173 chips. ACPICA mostly updates its debug infrastructure and adds a number of fixes and cleanups for a good measure. The Operating Performance Points (OPP) framework is updated with new DT bindings and support for them among other things. We have a few updates of the generic power domains framework and a reorganization of the ACPI device enumeration code and bus type operations. And a lot of fixes and cleanups all over. Included is one branch from the MFD tree as it contains some PM-related driver core and ACPI PM changes a few other commits are based on. Specifics: - ACPICA update to upstream revision 20150818 including method tracing extensions to allow more in-depth AML debugging in the kernel and a number of assorted fixes and cleanups (Bob Moore, Lv Zheng, Markus Elfring). - ACPI sysfs code updates and a documentation update related to AML method tracing (Lv Zheng). - ACPI EC driver fix related to serialized evaluations of _Qxx methods and ACPI tools updates allowing the EC userspace tool to be built from the kernel source (Lv Zheng). - ACPI processor driver updates preparing it for future introduction of CPPC support and ACPI PCC mailbox driver updates (Ashwin Chaugule). - ACPI interrupts enumeration fix for a regression related to the handling of IRQ attribute conflicts between MADT and the ACPI namespace (Jiang Liu). - Fixes related to ACPI device PM (Mika Westerberg, Srinidhi Kasagar). - ACPI device registration code reorganization to separate the sysfs-related code and bus type operations from the rest (Rafael J Wysocki). - Assorted cleanups in the ACPI core (Jarkko Nikula, Mathias Krause, Andy Shevchenko, Rafael J Wysocki, Nicolas Iooss). - ACPI cpufreq driver and ia64 cpufreq driver fixes and cleanups (Pan Xinhui, Rafael J Wysocki). - cpufreq core cleanups on top of the previous changes allowing it to preseve its sysfs directories over system suspend/resume (Viresh Kumar, Rafael J Wysocki, Sebastian Andrzej Siewior). - cpufreq fixes and cleanups related to governors (Viresh Kumar). - cpufreq updates (core and the cpufreq-dt driver) related to the turbo/boost mode support (Viresh Kumar, Bartlomiej Zolnierkiewicz). - New DT bindings for Operating Performance Points (OPP), support for them in the OPP framework and in the cpufreq-dt driver plus related OPP framework fixes and cleanups (Viresh Kumar). - cpufreq powernv driver updates (Shilpasri G Bhat). - New cpufreq driver for Mediatek MT8173 (Pi-Cheng Chen). - Assorted cpufreq driver (speedstep-lib, sfi, integrator) cleanups and fixes (Abhilash Jindal, Andrzej Hajda, Cristian Ardelean). - intel_pstate driver updates including Skylake-S support, support for enabling HW P-states per CPU and an additional vendor bypass list entry (Kristen Carlson Accardi, Chen Yu, Ethan Zhao). - cpuidle core fixes related to the handling of coupled idle states (Xunlei Pang). - intel_idle driver updates including Skylake Client support and support for freeze-mode-specific idle states (Len Brown). - Driver core updates related to power management (Andy Shevchenko, Rafael J Wysocki). - Generic power domains framework fixes and cleanups (Jon Hunter, Geert Uytterhoeven, Rajendra Nayak, Ulf Hansson). - Device PM QoS framework update to allow the latency tolerance setting to be exposed to user space via sysfs (Mika Westerberg). - devfreq support for PPMUv2 in Exynos5433 and a fix for an incorrect exynos-ppmu DT binding (Chanwoo Choi, Javier Martinez Canillas). - System sleep support updates (Alan Stern, Len Brown, SungEun Kim). - rockchip-io AVS support updates (Heiko Stuebner). - PM core clocks support fixup (Colin Ian King). - Power capping RAPL driver update including support for Skylake H/S and Broadwell-H (Radivoje Jovanovic, Seiichi Ikarashi). - Generic device properties framework fixes related to the handling of static (driver-provided) property sets (Andy Shevchenko). - turbostat and cpupower updates (Len Brown, Shilpasri G Bhat, Shreyas B Prabhu)" * tag 'pm+acpi-4.3-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm: (180 commits) cpufreq: speedstep-lib: Use monotonic clock cpufreq: powernv: Increase the verbosity of OCC console messages cpufreq: sfi: use kmemdup rather than duplicating its implementation cpufreq: drop !cpufreq_driver check from cpufreq_parse_governor() cpufreq: rename cpufreq_real_policy as cpufreq_user_policy cpufreq: remove redundant 'policy' field from user_policy cpufreq: remove redundant 'governor' field from user_policy cpufreq: update user_policy.* on success cpufreq: use memcpy() to copy policy cpufreq: remove redundant CPUFREQ_INCOMPATIBLE notifier event cpufreq: mediatek: Add MT8173 cpufreq driver dt-bindings: mediatek: Add MT8173 CPU DVFS clock bindings PM / Domains: Fix typo in description of genpd_dev_pm_detach() PM / Domains: Remove unusable governor dummies PM / Domains: Make pm_genpd_init() available to modules PM / domains: Align column headers and data in pm_genpd_summary output powercap / RAPL: disable the 2nd power limit properly tools: cpupower: Fix error when running cpupower monitor PM / OPP: Drop unlikely before IS_ERR(_OR_NULL) PM / OPP: Fix static checker warning (broken 64bit big endian systems) ...
759 lines
20 KiB
C
759 lines
20 KiB
C
/*
|
|
* drivers/base/dd.c - The core device/driver interactions.
|
|
*
|
|
* This file contains the (sometimes tricky) code that controls the
|
|
* interactions between devices and drivers, which primarily includes
|
|
* driver binding and unbinding.
|
|
*
|
|
* All of this code used to exist in drivers/base/bus.c, but was
|
|
* relocated to here in the name of compartmentalization (since it wasn't
|
|
* strictly code just for the 'struct bus_type'.
|
|
*
|
|
* Copyright (c) 2002-5 Patrick Mochel
|
|
* Copyright (c) 2002-3 Open Source Development Labs
|
|
* Copyright (c) 2007-2009 Greg Kroah-Hartman <gregkh@suse.de>
|
|
* Copyright (c) 2007-2009 Novell Inc.
|
|
*
|
|
* This file is released under the GPLv2
|
|
*/
|
|
|
|
#include <linux/device.h>
|
|
#include <linux/delay.h>
|
|
#include <linux/module.h>
|
|
#include <linux/kthread.h>
|
|
#include <linux/wait.h>
|
|
#include <linux/async.h>
|
|
#include <linux/pm_runtime.h>
|
|
#include <linux/pinctrl/devinfo.h>
|
|
|
|
#include "base.h"
|
|
#include "power/power.h"
|
|
|
|
/*
|
|
* Deferred Probe infrastructure.
|
|
*
|
|
* Sometimes driver probe order matters, but the kernel doesn't always have
|
|
* dependency information which means some drivers will get probed before a
|
|
* resource it depends on is available. For example, an SDHCI driver may
|
|
* first need a GPIO line from an i2c GPIO controller before it can be
|
|
* initialized. If a required resource is not available yet, a driver can
|
|
* request probing to be deferred by returning -EPROBE_DEFER from its probe hook
|
|
*
|
|
* Deferred probe maintains two lists of devices, a pending list and an active
|
|
* list. A driver returning -EPROBE_DEFER causes the device to be added to the
|
|
* pending list. A successful driver probe will trigger moving all devices
|
|
* from the pending to the active list so that the workqueue will eventually
|
|
* retry them.
|
|
*
|
|
* The deferred_probe_mutex must be held any time the deferred_probe_*_list
|
|
* of the (struct device*)->p->deferred_probe pointers are manipulated
|
|
*/
|
|
static DEFINE_MUTEX(deferred_probe_mutex);
|
|
static LIST_HEAD(deferred_probe_pending_list);
|
|
static LIST_HEAD(deferred_probe_active_list);
|
|
static struct workqueue_struct *deferred_wq;
|
|
static atomic_t deferred_trigger_count = ATOMIC_INIT(0);
|
|
|
|
/*
|
|
* deferred_probe_work_func() - Retry probing devices in the active list.
|
|
*/
|
|
static void deferred_probe_work_func(struct work_struct *work)
|
|
{
|
|
struct device *dev;
|
|
struct device_private *private;
|
|
/*
|
|
* This block processes every device in the deferred 'active' list.
|
|
* Each device is removed from the active list and passed to
|
|
* bus_probe_device() to re-attempt the probe. The loop continues
|
|
* until every device in the active list is removed and retried.
|
|
*
|
|
* Note: Once the device is removed from the list and the mutex is
|
|
* released, it is possible for the device get freed by another thread
|
|
* and cause a illegal pointer dereference. This code uses
|
|
* get/put_device() to ensure the device structure cannot disappear
|
|
* from under our feet.
|
|
*/
|
|
mutex_lock(&deferred_probe_mutex);
|
|
while (!list_empty(&deferred_probe_active_list)) {
|
|
private = list_first_entry(&deferred_probe_active_list,
|
|
typeof(*dev->p), deferred_probe);
|
|
dev = private->device;
|
|
list_del_init(&private->deferred_probe);
|
|
|
|
get_device(dev);
|
|
|
|
/*
|
|
* Drop the mutex while probing each device; the probe path may
|
|
* manipulate the deferred list
|
|
*/
|
|
mutex_unlock(&deferred_probe_mutex);
|
|
|
|
/*
|
|
* Force the device to the end of the dpm_list since
|
|
* the PM code assumes that the order we add things to
|
|
* the list is a good order for suspend but deferred
|
|
* probe makes that very unsafe.
|
|
*/
|
|
device_pm_lock();
|
|
device_pm_move_last(dev);
|
|
device_pm_unlock();
|
|
|
|
dev_dbg(dev, "Retrying from deferred list\n");
|
|
bus_probe_device(dev);
|
|
|
|
mutex_lock(&deferred_probe_mutex);
|
|
|
|
put_device(dev);
|
|
}
|
|
mutex_unlock(&deferred_probe_mutex);
|
|
}
|
|
static DECLARE_WORK(deferred_probe_work, deferred_probe_work_func);
|
|
|
|
static void driver_deferred_probe_add(struct device *dev)
|
|
{
|
|
mutex_lock(&deferred_probe_mutex);
|
|
if (list_empty(&dev->p->deferred_probe)) {
|
|
dev_dbg(dev, "Added to deferred list\n");
|
|
list_add_tail(&dev->p->deferred_probe, &deferred_probe_pending_list);
|
|
}
|
|
mutex_unlock(&deferred_probe_mutex);
|
|
}
|
|
|
|
void driver_deferred_probe_del(struct device *dev)
|
|
{
|
|
mutex_lock(&deferred_probe_mutex);
|
|
if (!list_empty(&dev->p->deferred_probe)) {
|
|
dev_dbg(dev, "Removed from deferred list\n");
|
|
list_del_init(&dev->p->deferred_probe);
|
|
}
|
|
mutex_unlock(&deferred_probe_mutex);
|
|
}
|
|
|
|
static bool driver_deferred_probe_enable = false;
|
|
/**
|
|
* driver_deferred_probe_trigger() - Kick off re-probing deferred devices
|
|
*
|
|
* This functions moves all devices from the pending list to the active
|
|
* list and schedules the deferred probe workqueue to process them. It
|
|
* should be called anytime a driver is successfully bound to a device.
|
|
*
|
|
* Note, there is a race condition in multi-threaded probe. In the case where
|
|
* more than one device is probing at the same time, it is possible for one
|
|
* probe to complete successfully while another is about to defer. If the second
|
|
* depends on the first, then it will get put on the pending list after the
|
|
* trigger event has already occurred and will be stuck there.
|
|
*
|
|
* The atomic 'deferred_trigger_count' is used to determine if a successful
|
|
* trigger has occurred in the midst of probing a driver. If the trigger count
|
|
* changes in the midst of a probe, then deferred processing should be triggered
|
|
* again.
|
|
*/
|
|
static void driver_deferred_probe_trigger(void)
|
|
{
|
|
if (!driver_deferred_probe_enable)
|
|
return;
|
|
|
|
/*
|
|
* A successful probe means that all the devices in the pending list
|
|
* should be triggered to be reprobed. Move all the deferred devices
|
|
* into the active list so they can be retried by the workqueue
|
|
*/
|
|
mutex_lock(&deferred_probe_mutex);
|
|
atomic_inc(&deferred_trigger_count);
|
|
list_splice_tail_init(&deferred_probe_pending_list,
|
|
&deferred_probe_active_list);
|
|
mutex_unlock(&deferred_probe_mutex);
|
|
|
|
/*
|
|
* Kick the re-probe thread. It may already be scheduled, but it is
|
|
* safe to kick it again.
|
|
*/
|
|
queue_work(deferred_wq, &deferred_probe_work);
|
|
}
|
|
|
|
/**
|
|
* deferred_probe_initcall() - Enable probing of deferred devices
|
|
*
|
|
* We don't want to get in the way when the bulk of drivers are getting probed.
|
|
* Instead, this initcall makes sure that deferred probing is delayed until
|
|
* late_initcall time.
|
|
*/
|
|
static int deferred_probe_initcall(void)
|
|
{
|
|
deferred_wq = create_singlethread_workqueue("deferwq");
|
|
if (WARN_ON(!deferred_wq))
|
|
return -ENOMEM;
|
|
|
|
driver_deferred_probe_enable = true;
|
|
driver_deferred_probe_trigger();
|
|
/* Sort as many dependencies as possible before exiting initcalls */
|
|
flush_workqueue(deferred_wq);
|
|
return 0;
|
|
}
|
|
late_initcall(deferred_probe_initcall);
|
|
|
|
static void driver_bound(struct device *dev)
|
|
{
|
|
if (klist_node_attached(&dev->p->knode_driver)) {
|
|
printk(KERN_WARNING "%s: device %s already bound\n",
|
|
__func__, kobject_name(&dev->kobj));
|
|
return;
|
|
}
|
|
|
|
pr_debug("driver: '%s': %s: bound to device '%s'\n", dev->driver->name,
|
|
__func__, dev_name(dev));
|
|
|
|
klist_add_tail(&dev->p->knode_driver, &dev->driver->p->klist_devices);
|
|
|
|
/*
|
|
* Make sure the device is no longer in one of the deferred lists and
|
|
* kick off retrying all pending devices
|
|
*/
|
|
driver_deferred_probe_del(dev);
|
|
driver_deferred_probe_trigger();
|
|
|
|
if (dev->bus)
|
|
blocking_notifier_call_chain(&dev->bus->p->bus_notifier,
|
|
BUS_NOTIFY_BOUND_DRIVER, dev);
|
|
}
|
|
|
|
static int driver_sysfs_add(struct device *dev)
|
|
{
|
|
int ret;
|
|
|
|
if (dev->bus)
|
|
blocking_notifier_call_chain(&dev->bus->p->bus_notifier,
|
|
BUS_NOTIFY_BIND_DRIVER, dev);
|
|
|
|
ret = sysfs_create_link(&dev->driver->p->kobj, &dev->kobj,
|
|
kobject_name(&dev->kobj));
|
|
if (ret == 0) {
|
|
ret = sysfs_create_link(&dev->kobj, &dev->driver->p->kobj,
|
|
"driver");
|
|
if (ret)
|
|
sysfs_remove_link(&dev->driver->p->kobj,
|
|
kobject_name(&dev->kobj));
|
|
}
|
|
return ret;
|
|
}
|
|
|
|
static void driver_sysfs_remove(struct device *dev)
|
|
{
|
|
struct device_driver *drv = dev->driver;
|
|
|
|
if (drv) {
|
|
sysfs_remove_link(&drv->p->kobj, kobject_name(&dev->kobj));
|
|
sysfs_remove_link(&dev->kobj, "driver");
|
|
}
|
|
}
|
|
|
|
/**
|
|
* device_bind_driver - bind a driver to one device.
|
|
* @dev: device.
|
|
*
|
|
* Allow manual attachment of a driver to a device.
|
|
* Caller must have already set @dev->driver.
|
|
*
|
|
* Note that this does not modify the bus reference count
|
|
* nor take the bus's rwsem. Please verify those are accounted
|
|
* for before calling this. (It is ok to call with no other effort
|
|
* from a driver's probe() method.)
|
|
*
|
|
* This function must be called with the device lock held.
|
|
*/
|
|
int device_bind_driver(struct device *dev)
|
|
{
|
|
int ret;
|
|
|
|
ret = driver_sysfs_add(dev);
|
|
if (!ret)
|
|
driver_bound(dev);
|
|
return ret;
|
|
}
|
|
EXPORT_SYMBOL_GPL(device_bind_driver);
|
|
|
|
static atomic_t probe_count = ATOMIC_INIT(0);
|
|
static DECLARE_WAIT_QUEUE_HEAD(probe_waitqueue);
|
|
|
|
static int really_probe(struct device *dev, struct device_driver *drv)
|
|
{
|
|
int ret = 0;
|
|
int local_trigger_count = atomic_read(&deferred_trigger_count);
|
|
|
|
atomic_inc(&probe_count);
|
|
pr_debug("bus: '%s': %s: probing driver %s with device %s\n",
|
|
drv->bus->name, __func__, drv->name, dev_name(dev));
|
|
WARN_ON(!list_empty(&dev->devres_head));
|
|
|
|
dev->driver = drv;
|
|
|
|
/* If using pinctrl, bind pins now before probing */
|
|
ret = pinctrl_bind_pins(dev);
|
|
if (ret)
|
|
goto probe_failed;
|
|
|
|
if (driver_sysfs_add(dev)) {
|
|
printk(KERN_ERR "%s: driver_sysfs_add(%s) failed\n",
|
|
__func__, dev_name(dev));
|
|
goto probe_failed;
|
|
}
|
|
|
|
if (dev->pm_domain && dev->pm_domain->activate) {
|
|
ret = dev->pm_domain->activate(dev);
|
|
if (ret)
|
|
goto probe_failed;
|
|
}
|
|
|
|
/*
|
|
* Ensure devices are listed in devices_kset in correct order
|
|
* It's important to move Dev to the end of devices_kset before
|
|
* calling .probe, because it could be recursive and parent Dev
|
|
* should always go first
|
|
*/
|
|
devices_kset_move_last(dev);
|
|
|
|
if (dev->bus->probe) {
|
|
ret = dev->bus->probe(dev);
|
|
if (ret)
|
|
goto probe_failed;
|
|
} else if (drv->probe) {
|
|
ret = drv->probe(dev);
|
|
if (ret)
|
|
goto probe_failed;
|
|
}
|
|
|
|
if (dev->pm_domain && dev->pm_domain->sync)
|
|
dev->pm_domain->sync(dev);
|
|
|
|
driver_bound(dev);
|
|
ret = 1;
|
|
pr_debug("bus: '%s': %s: bound device %s to driver %s\n",
|
|
drv->bus->name, __func__, dev_name(dev), drv->name);
|
|
goto done;
|
|
|
|
probe_failed:
|
|
devres_release_all(dev);
|
|
driver_sysfs_remove(dev);
|
|
dev->driver = NULL;
|
|
dev_set_drvdata(dev, NULL);
|
|
if (dev->pm_domain && dev->pm_domain->dismiss)
|
|
dev->pm_domain->dismiss(dev);
|
|
|
|
switch (ret) {
|
|
case -EPROBE_DEFER:
|
|
/* Driver requested deferred probing */
|
|
dev_dbg(dev, "Driver %s requests probe deferral\n", drv->name);
|
|
driver_deferred_probe_add(dev);
|
|
/* Did a trigger occur while probing? Need to re-trigger if yes */
|
|
if (local_trigger_count != atomic_read(&deferred_trigger_count))
|
|
driver_deferred_probe_trigger();
|
|
break;
|
|
case -ENODEV:
|
|
case -ENXIO:
|
|
pr_debug("%s: probe of %s rejects match %d\n",
|
|
drv->name, dev_name(dev), ret);
|
|
break;
|
|
default:
|
|
/* driver matched but the probe failed */
|
|
printk(KERN_WARNING
|
|
"%s: probe of %s failed with error %d\n",
|
|
drv->name, dev_name(dev), ret);
|
|
}
|
|
/*
|
|
* Ignore errors returned by ->probe so that the next driver can try
|
|
* its luck.
|
|
*/
|
|
ret = 0;
|
|
done:
|
|
atomic_dec(&probe_count);
|
|
wake_up(&probe_waitqueue);
|
|
return ret;
|
|
}
|
|
|
|
/**
|
|
* driver_probe_done
|
|
* Determine if the probe sequence is finished or not.
|
|
*
|
|
* Should somehow figure out how to use a semaphore, not an atomic variable...
|
|
*/
|
|
int driver_probe_done(void)
|
|
{
|
|
pr_debug("%s: probe_count = %d\n", __func__,
|
|
atomic_read(&probe_count));
|
|
if (atomic_read(&probe_count))
|
|
return -EBUSY;
|
|
return 0;
|
|
}
|
|
|
|
/**
|
|
* wait_for_device_probe
|
|
* Wait for device probing to be completed.
|
|
*/
|
|
void wait_for_device_probe(void)
|
|
{
|
|
/* wait for the known devices to complete their probing */
|
|
wait_event(probe_waitqueue, atomic_read(&probe_count) == 0);
|
|
async_synchronize_full();
|
|
}
|
|
EXPORT_SYMBOL_GPL(wait_for_device_probe);
|
|
|
|
/**
|
|
* driver_probe_device - attempt to bind device & driver together
|
|
* @drv: driver to bind a device to
|
|
* @dev: device to try to bind to the driver
|
|
*
|
|
* This function returns -ENODEV if the device is not registered,
|
|
* 1 if the device is bound successfully and 0 otherwise.
|
|
*
|
|
* This function must be called with @dev lock held. When called for a
|
|
* USB interface, @dev->parent lock must be held as well.
|
|
*
|
|
* If the device has a parent, runtime-resume the parent before driver probing.
|
|
*/
|
|
int driver_probe_device(struct device_driver *drv, struct device *dev)
|
|
{
|
|
int ret = 0;
|
|
|
|
if (!device_is_registered(dev))
|
|
return -ENODEV;
|
|
|
|
pr_debug("bus: '%s': %s: matched device %s with driver %s\n",
|
|
drv->bus->name, __func__, dev_name(dev), drv->name);
|
|
|
|
if (dev->parent)
|
|
pm_runtime_get_sync(dev->parent);
|
|
|
|
pm_runtime_barrier(dev);
|
|
ret = really_probe(dev, drv);
|
|
pm_request_idle(dev);
|
|
|
|
if (dev->parent)
|
|
pm_runtime_put(dev->parent);
|
|
|
|
return ret;
|
|
}
|
|
|
|
bool driver_allows_async_probing(struct device_driver *drv)
|
|
{
|
|
switch (drv->probe_type) {
|
|
case PROBE_PREFER_ASYNCHRONOUS:
|
|
return true;
|
|
|
|
case PROBE_FORCE_SYNCHRONOUS:
|
|
return false;
|
|
|
|
default:
|
|
if (module_requested_async_probing(drv->owner))
|
|
return true;
|
|
|
|
return false;
|
|
}
|
|
}
|
|
|
|
struct device_attach_data {
|
|
struct device *dev;
|
|
|
|
/*
|
|
* Indicates whether we are are considering asynchronous probing or
|
|
* not. Only initial binding after device or driver registration
|
|
* (including deferral processing) may be done asynchronously, the
|
|
* rest is always synchronous, as we expect it is being done by
|
|
* request from userspace.
|
|
*/
|
|
bool check_async;
|
|
|
|
/*
|
|
* Indicates if we are binding synchronous or asynchronous drivers.
|
|
* When asynchronous probing is enabled we'll execute 2 passes
|
|
* over drivers: first pass doing synchronous probing and second
|
|
* doing asynchronous probing (if synchronous did not succeed -
|
|
* most likely because there was no driver requiring synchronous
|
|
* probing - and we found asynchronous driver during first pass).
|
|
* The 2 passes are done because we can't shoot asynchronous
|
|
* probe for given device and driver from bus_for_each_drv() since
|
|
* driver pointer is not guaranteed to stay valid once
|
|
* bus_for_each_drv() iterates to the next driver on the bus.
|
|
*/
|
|
bool want_async;
|
|
|
|
/*
|
|
* We'll set have_async to 'true' if, while scanning for matching
|
|
* driver, we'll encounter one that requests asynchronous probing.
|
|
*/
|
|
bool have_async;
|
|
};
|
|
|
|
static int __device_attach_driver(struct device_driver *drv, void *_data)
|
|
{
|
|
struct device_attach_data *data = _data;
|
|
struct device *dev = data->dev;
|
|
bool async_allowed;
|
|
|
|
/*
|
|
* Check if device has already been claimed. This may
|
|
* happen with driver loading, device discovery/registration,
|
|
* and deferred probe processing happens all at once with
|
|
* multiple threads.
|
|
*/
|
|
if (dev->driver)
|
|
return -EBUSY;
|
|
|
|
if (!driver_match_device(drv, dev))
|
|
return 0;
|
|
|
|
async_allowed = driver_allows_async_probing(drv);
|
|
|
|
if (async_allowed)
|
|
data->have_async = true;
|
|
|
|
if (data->check_async && async_allowed != data->want_async)
|
|
return 0;
|
|
|
|
return driver_probe_device(drv, dev);
|
|
}
|
|
|
|
static void __device_attach_async_helper(void *_dev, async_cookie_t cookie)
|
|
{
|
|
struct device *dev = _dev;
|
|
struct device_attach_data data = {
|
|
.dev = dev,
|
|
.check_async = true,
|
|
.want_async = true,
|
|
};
|
|
|
|
device_lock(dev);
|
|
|
|
if (dev->parent)
|
|
pm_runtime_get_sync(dev->parent);
|
|
|
|
bus_for_each_drv(dev->bus, NULL, &data, __device_attach_driver);
|
|
dev_dbg(dev, "async probe completed\n");
|
|
|
|
pm_request_idle(dev);
|
|
|
|
if (dev->parent)
|
|
pm_runtime_put(dev->parent);
|
|
|
|
device_unlock(dev);
|
|
|
|
put_device(dev);
|
|
}
|
|
|
|
static int __device_attach(struct device *dev, bool allow_async)
|
|
{
|
|
int ret = 0;
|
|
|
|
device_lock(dev);
|
|
if (dev->driver) {
|
|
if (klist_node_attached(&dev->p->knode_driver)) {
|
|
ret = 1;
|
|
goto out_unlock;
|
|
}
|
|
ret = device_bind_driver(dev);
|
|
if (ret == 0)
|
|
ret = 1;
|
|
else {
|
|
dev->driver = NULL;
|
|
ret = 0;
|
|
}
|
|
} else {
|
|
struct device_attach_data data = {
|
|
.dev = dev,
|
|
.check_async = allow_async,
|
|
.want_async = false,
|
|
};
|
|
|
|
if (dev->parent)
|
|
pm_runtime_get_sync(dev->parent);
|
|
|
|
ret = bus_for_each_drv(dev->bus, NULL, &data,
|
|
__device_attach_driver);
|
|
if (!ret && allow_async && data.have_async) {
|
|
/*
|
|
* If we could not find appropriate driver
|
|
* synchronously and we are allowed to do
|
|
* async probes and there are drivers that
|
|
* want to probe asynchronously, we'll
|
|
* try them.
|
|
*/
|
|
dev_dbg(dev, "scheduling asynchronous probe\n");
|
|
get_device(dev);
|
|
async_schedule(__device_attach_async_helper, dev);
|
|
} else {
|
|
pm_request_idle(dev);
|
|
}
|
|
|
|
if (dev->parent)
|
|
pm_runtime_put(dev->parent);
|
|
}
|
|
out_unlock:
|
|
device_unlock(dev);
|
|
return ret;
|
|
}
|
|
|
|
/**
|
|
* device_attach - try to attach device to a driver.
|
|
* @dev: device.
|
|
*
|
|
* Walk the list of drivers that the bus has and call
|
|
* driver_probe_device() for each pair. If a compatible
|
|
* pair is found, break out and return.
|
|
*
|
|
* Returns 1 if the device was bound to a driver;
|
|
* 0 if no matching driver was found;
|
|
* -ENODEV if the device is not registered.
|
|
*
|
|
* When called for a USB interface, @dev->parent lock must be held.
|
|
*/
|
|
int device_attach(struct device *dev)
|
|
{
|
|
return __device_attach(dev, false);
|
|
}
|
|
EXPORT_SYMBOL_GPL(device_attach);
|
|
|
|
void device_initial_probe(struct device *dev)
|
|
{
|
|
__device_attach(dev, true);
|
|
}
|
|
|
|
static int __driver_attach(struct device *dev, void *data)
|
|
{
|
|
struct device_driver *drv = data;
|
|
|
|
/*
|
|
* Lock device and try to bind to it. We drop the error
|
|
* here and always return 0, because we need to keep trying
|
|
* to bind to devices and some drivers will return an error
|
|
* simply if it didn't support the device.
|
|
*
|
|
* driver_probe_device() will spit a warning if there
|
|
* is an error.
|
|
*/
|
|
|
|
if (!driver_match_device(drv, dev))
|
|
return 0;
|
|
|
|
if (dev->parent) /* Needed for USB */
|
|
device_lock(dev->parent);
|
|
device_lock(dev);
|
|
if (!dev->driver)
|
|
driver_probe_device(drv, dev);
|
|
device_unlock(dev);
|
|
if (dev->parent)
|
|
device_unlock(dev->parent);
|
|
|
|
return 0;
|
|
}
|
|
|
|
/**
|
|
* driver_attach - try to bind driver to devices.
|
|
* @drv: driver.
|
|
*
|
|
* Walk the list of devices that the bus has on it and try to
|
|
* match the driver with each one. If driver_probe_device()
|
|
* returns 0 and the @dev->driver is set, we've found a
|
|
* compatible pair.
|
|
*/
|
|
int driver_attach(struct device_driver *drv)
|
|
{
|
|
return bus_for_each_dev(drv->bus, NULL, drv, __driver_attach);
|
|
}
|
|
EXPORT_SYMBOL_GPL(driver_attach);
|
|
|
|
/*
|
|
* __device_release_driver() must be called with @dev lock held.
|
|
* When called for a USB interface, @dev->parent lock must be held as well.
|
|
*/
|
|
static void __device_release_driver(struct device *dev)
|
|
{
|
|
struct device_driver *drv;
|
|
|
|
drv = dev->driver;
|
|
if (drv) {
|
|
if (driver_allows_async_probing(drv))
|
|
async_synchronize_full();
|
|
|
|
pm_runtime_get_sync(dev);
|
|
|
|
driver_sysfs_remove(dev);
|
|
|
|
if (dev->bus)
|
|
blocking_notifier_call_chain(&dev->bus->p->bus_notifier,
|
|
BUS_NOTIFY_UNBIND_DRIVER,
|
|
dev);
|
|
|
|
pm_runtime_put_sync(dev);
|
|
|
|
if (dev->bus && dev->bus->remove)
|
|
dev->bus->remove(dev);
|
|
else if (drv->remove)
|
|
drv->remove(dev);
|
|
devres_release_all(dev);
|
|
dev->driver = NULL;
|
|
dev_set_drvdata(dev, NULL);
|
|
if (dev->pm_domain && dev->pm_domain->dismiss)
|
|
dev->pm_domain->dismiss(dev);
|
|
|
|
klist_remove(&dev->p->knode_driver);
|
|
if (dev->bus)
|
|
blocking_notifier_call_chain(&dev->bus->p->bus_notifier,
|
|
BUS_NOTIFY_UNBOUND_DRIVER,
|
|
dev);
|
|
|
|
}
|
|
}
|
|
|
|
/**
|
|
* device_release_driver - manually detach device from driver.
|
|
* @dev: device.
|
|
*
|
|
* Manually detach device from driver.
|
|
* When called for a USB interface, @dev->parent lock must be held.
|
|
*/
|
|
void device_release_driver(struct device *dev)
|
|
{
|
|
/*
|
|
* If anyone calls device_release_driver() recursively from
|
|
* within their ->remove callback for the same device, they
|
|
* will deadlock right here.
|
|
*/
|
|
device_lock(dev);
|
|
__device_release_driver(dev);
|
|
device_unlock(dev);
|
|
}
|
|
EXPORT_SYMBOL_GPL(device_release_driver);
|
|
|
|
/**
|
|
* driver_detach - detach driver from all devices it controls.
|
|
* @drv: driver.
|
|
*/
|
|
void driver_detach(struct device_driver *drv)
|
|
{
|
|
struct device_private *dev_prv;
|
|
struct device *dev;
|
|
|
|
for (;;) {
|
|
spin_lock(&drv->p->klist_devices.k_lock);
|
|
if (list_empty(&drv->p->klist_devices.k_list)) {
|
|
spin_unlock(&drv->p->klist_devices.k_lock);
|
|
break;
|
|
}
|
|
dev_prv = list_entry(drv->p->klist_devices.k_list.prev,
|
|
struct device_private,
|
|
knode_driver.n_node);
|
|
dev = dev_prv->device;
|
|
get_device(dev);
|
|
spin_unlock(&drv->p->klist_devices.k_lock);
|
|
|
|
if (dev->parent) /* Needed for USB */
|
|
device_lock(dev->parent);
|
|
device_lock(dev);
|
|
if (dev->driver == drv)
|
|
__device_release_driver(dev);
|
|
device_unlock(dev);
|
|
if (dev->parent)
|
|
device_unlock(dev->parent);
|
|
put_device(dev);
|
|
}
|
|
}
|