![Alan Stern](/assets/img/avatar_default.png)
This patch (as877) adds a "last_busy" field to struct usb_device, for use by the autosuspend framework. Now if an autosuspend call comes at a time when the device isn't busy but hasn't yet been idle for long enough, the timer can be set to exactly the desired value. And we will be ready to handle things like HID drivers, which can't maintain a useful usage count and must rely on the time-of-last-use to decide when to autosuspend. The patch also makes some related minor improvements: Move the calls to the autosuspend condition-checking routine into usb_suspend_both(), which is the only place where it really matters. If the autosuspend timer is already running, don't stop and restart it. Replace immediate returns with gotos so that the optional debugging ouput won't be bypassed. If autoresume is disabled but the device is already awake, don't return an error for an autoresume call. Don't try to autoresume a device if it isn't suspended. (Yes, this undercuts the previous change -- so sue me.) Don't duplicate existing code in the autosuspend work routine. Fix the kerneldoc in usb_autopm_put_interface(): If an autoresume call fails, the usage counter is left unchanged. Signed-off-by: Alan Stern <stern@rowland.harvard.edu> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
1757 lines
49 KiB
C
1757 lines
49 KiB
C
/*
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* (C) Copyright Linus Torvalds 1999
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* (C) Copyright Johannes Erdfelt 1999-2001
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* (C) Copyright Andreas Gal 1999
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* (C) Copyright Gregory P. Smith 1999
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* (C) Copyright Deti Fliegl 1999
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* (C) Copyright Randy Dunlap 2000
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* (C) Copyright David Brownell 2000-2002
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*
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* This program is free software; you can redistribute it and/or modify it
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* under the terms of the GNU General Public License as published by the
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* Free Software Foundation; either version 2 of the License, or (at your
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* option) any later version.
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*
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* This program is distributed in the hope that it will be useful, but
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* WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
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* or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
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* for more details.
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*
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* You should have received a copy of the GNU General Public License
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* along with this program; if not, write to the Free Software Foundation,
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* Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
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*/
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#include <linux/module.h>
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#include <linux/version.h>
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#include <linux/kernel.h>
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#include <linux/slab.h>
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#include <linux/completion.h>
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#include <linux/utsname.h>
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#include <linux/mm.h>
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#include <asm/io.h>
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#include <asm/scatterlist.h>
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#include <linux/device.h>
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#include <linux/dma-mapping.h>
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#include <linux/mutex.h>
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#include <asm/irq.h>
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#include <asm/byteorder.h>
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#include <linux/platform_device.h>
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#include <linux/workqueue.h>
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#include <linux/usb.h>
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#include "usb.h"
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#include "hcd.h"
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#include "hub.h"
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/*-------------------------------------------------------------------------*/
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/*
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* USB Host Controller Driver framework
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*
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* Plugs into usbcore (usb_bus) and lets HCDs share code, minimizing
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* HCD-specific behaviors/bugs.
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*
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* This does error checks, tracks devices and urbs, and delegates to a
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* "hc_driver" only for code (and data) that really needs to know about
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* hardware differences. That includes root hub registers, i/o queues,
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* and so on ... but as little else as possible.
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*
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* Shared code includes most of the "root hub" code (these are emulated,
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* though each HC's hardware works differently) and PCI glue, plus request
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* tracking overhead. The HCD code should only block on spinlocks or on
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* hardware handshaking; blocking on software events (such as other kernel
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* threads releasing resources, or completing actions) is all generic.
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*
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* Happens the USB 2.0 spec says this would be invisible inside the "USBD",
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* and includes mostly a "HCDI" (HCD Interface) along with some APIs used
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* only by the hub driver ... and that neither should be seen or used by
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* usb client device drivers.
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*
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* Contributors of ideas or unattributed patches include: David Brownell,
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* Roman Weissgaerber, Rory Bolt, Greg Kroah-Hartman, ...
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*
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* HISTORY:
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* 2002-02-21 Pull in most of the usb_bus support from usb.c; some
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* associated cleanup. "usb_hcd" still != "usb_bus".
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* 2001-12-12 Initial patch version for Linux 2.5.1 kernel.
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*/
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/*-------------------------------------------------------------------------*/
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/* host controllers we manage */
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LIST_HEAD (usb_bus_list);
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EXPORT_SYMBOL_GPL (usb_bus_list);
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/* used when allocating bus numbers */
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#define USB_MAXBUS 64
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struct usb_busmap {
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unsigned long busmap [USB_MAXBUS / (8*sizeof (unsigned long))];
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};
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static struct usb_busmap busmap;
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/* used when updating list of hcds */
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DEFINE_MUTEX(usb_bus_list_lock); /* exported only for usbfs */
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EXPORT_SYMBOL_GPL (usb_bus_list_lock);
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/* used for controlling access to virtual root hubs */
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static DEFINE_SPINLOCK(hcd_root_hub_lock);
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/* used when updating hcd data */
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static DEFINE_SPINLOCK(hcd_data_lock);
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/* wait queue for synchronous unlinks */
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DECLARE_WAIT_QUEUE_HEAD(usb_kill_urb_queue);
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/*-------------------------------------------------------------------------*/
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/*
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* Sharable chunks of root hub code.
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*/
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/*-------------------------------------------------------------------------*/
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#define KERNEL_REL ((LINUX_VERSION_CODE >> 16) & 0x0ff)
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#define KERNEL_VER ((LINUX_VERSION_CODE >> 8) & 0x0ff)
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/* usb 2.0 root hub device descriptor */
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static const u8 usb2_rh_dev_descriptor [18] = {
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0x12, /* __u8 bLength; */
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0x01, /* __u8 bDescriptorType; Device */
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0x00, 0x02, /* __le16 bcdUSB; v2.0 */
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0x09, /* __u8 bDeviceClass; HUB_CLASSCODE */
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0x00, /* __u8 bDeviceSubClass; */
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0x01, /* __u8 bDeviceProtocol; [ usb 2.0 single TT ]*/
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0x40, /* __u8 bMaxPacketSize0; 64 Bytes */
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0x00, 0x00, /* __le16 idVendor; */
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0x00, 0x00, /* __le16 idProduct; */
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KERNEL_VER, KERNEL_REL, /* __le16 bcdDevice */
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0x03, /* __u8 iManufacturer; */
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0x02, /* __u8 iProduct; */
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0x01, /* __u8 iSerialNumber; */
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0x01 /* __u8 bNumConfigurations; */
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};
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/* no usb 2.0 root hub "device qualifier" descriptor: one speed only */
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/* usb 1.1 root hub device descriptor */
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static const u8 usb11_rh_dev_descriptor [18] = {
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0x12, /* __u8 bLength; */
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0x01, /* __u8 bDescriptorType; Device */
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0x10, 0x01, /* __le16 bcdUSB; v1.1 */
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0x09, /* __u8 bDeviceClass; HUB_CLASSCODE */
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0x00, /* __u8 bDeviceSubClass; */
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0x00, /* __u8 bDeviceProtocol; [ low/full speeds only ] */
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0x40, /* __u8 bMaxPacketSize0; 64 Bytes */
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0x00, 0x00, /* __le16 idVendor; */
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0x00, 0x00, /* __le16 idProduct; */
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KERNEL_VER, KERNEL_REL, /* __le16 bcdDevice */
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0x03, /* __u8 iManufacturer; */
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0x02, /* __u8 iProduct; */
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0x01, /* __u8 iSerialNumber; */
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0x01 /* __u8 bNumConfigurations; */
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};
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/*-------------------------------------------------------------------------*/
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/* Configuration descriptors for our root hubs */
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static const u8 fs_rh_config_descriptor [] = {
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/* one configuration */
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0x09, /* __u8 bLength; */
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0x02, /* __u8 bDescriptorType; Configuration */
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0x19, 0x00, /* __le16 wTotalLength; */
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0x01, /* __u8 bNumInterfaces; (1) */
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0x01, /* __u8 bConfigurationValue; */
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0x00, /* __u8 iConfiguration; */
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0xc0, /* __u8 bmAttributes;
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Bit 7: must be set,
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6: Self-powered,
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5: Remote wakeup,
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4..0: resvd */
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0x00, /* __u8 MaxPower; */
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/* USB 1.1:
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* USB 2.0, single TT organization (mandatory):
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* one interface, protocol 0
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*
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* USB 2.0, multiple TT organization (optional):
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* two interfaces, protocols 1 (like single TT)
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* and 2 (multiple TT mode) ... config is
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* sometimes settable
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* NOT IMPLEMENTED
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*/
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/* one interface */
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0x09, /* __u8 if_bLength; */
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0x04, /* __u8 if_bDescriptorType; Interface */
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0x00, /* __u8 if_bInterfaceNumber; */
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0x00, /* __u8 if_bAlternateSetting; */
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0x01, /* __u8 if_bNumEndpoints; */
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0x09, /* __u8 if_bInterfaceClass; HUB_CLASSCODE */
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0x00, /* __u8 if_bInterfaceSubClass; */
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0x00, /* __u8 if_bInterfaceProtocol; [usb1.1 or single tt] */
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0x00, /* __u8 if_iInterface; */
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/* one endpoint (status change endpoint) */
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0x07, /* __u8 ep_bLength; */
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0x05, /* __u8 ep_bDescriptorType; Endpoint */
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0x81, /* __u8 ep_bEndpointAddress; IN Endpoint 1 */
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0x03, /* __u8 ep_bmAttributes; Interrupt */
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0x02, 0x00, /* __le16 ep_wMaxPacketSize; 1 + (MAX_ROOT_PORTS / 8) */
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0xff /* __u8 ep_bInterval; (255ms -- usb 2.0 spec) */
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};
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static const u8 hs_rh_config_descriptor [] = {
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/* one configuration */
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0x09, /* __u8 bLength; */
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0x02, /* __u8 bDescriptorType; Configuration */
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0x19, 0x00, /* __le16 wTotalLength; */
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0x01, /* __u8 bNumInterfaces; (1) */
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0x01, /* __u8 bConfigurationValue; */
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0x00, /* __u8 iConfiguration; */
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0xc0, /* __u8 bmAttributes;
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Bit 7: must be set,
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6: Self-powered,
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5: Remote wakeup,
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4..0: resvd */
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0x00, /* __u8 MaxPower; */
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/* USB 1.1:
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* USB 2.0, single TT organization (mandatory):
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* one interface, protocol 0
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*
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* USB 2.0, multiple TT organization (optional):
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* two interfaces, protocols 1 (like single TT)
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* and 2 (multiple TT mode) ... config is
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* sometimes settable
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* NOT IMPLEMENTED
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*/
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/* one interface */
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0x09, /* __u8 if_bLength; */
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0x04, /* __u8 if_bDescriptorType; Interface */
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0x00, /* __u8 if_bInterfaceNumber; */
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0x00, /* __u8 if_bAlternateSetting; */
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0x01, /* __u8 if_bNumEndpoints; */
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0x09, /* __u8 if_bInterfaceClass; HUB_CLASSCODE */
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0x00, /* __u8 if_bInterfaceSubClass; */
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0x00, /* __u8 if_bInterfaceProtocol; [usb1.1 or single tt] */
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0x00, /* __u8 if_iInterface; */
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/* one endpoint (status change endpoint) */
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0x07, /* __u8 ep_bLength; */
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0x05, /* __u8 ep_bDescriptorType; Endpoint */
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0x81, /* __u8 ep_bEndpointAddress; IN Endpoint 1 */
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0x03, /* __u8 ep_bmAttributes; Interrupt */
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/* __le16 ep_wMaxPacketSize; 1 + (MAX_ROOT_PORTS / 8)
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* see hub.c:hub_configure() for details. */
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(USB_MAXCHILDREN + 1 + 7) / 8, 0x00,
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0x0c /* __u8 ep_bInterval; (256ms -- usb 2.0 spec) */
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};
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/*-------------------------------------------------------------------------*/
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/*
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* helper routine for returning string descriptors in UTF-16LE
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* input can actually be ISO-8859-1; ASCII is its 7-bit subset
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*/
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static int ascii2utf (char *s, u8 *utf, int utfmax)
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{
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int retval;
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for (retval = 0; *s && utfmax > 1; utfmax -= 2, retval += 2) {
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*utf++ = *s++;
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*utf++ = 0;
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}
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if (utfmax > 0) {
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*utf = *s;
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++retval;
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}
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return retval;
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}
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/*
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* rh_string - provides manufacturer, product and serial strings for root hub
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* @id: the string ID number (1: serial number, 2: product, 3: vendor)
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* @hcd: the host controller for this root hub
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* @type: string describing our driver
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* @data: return packet in UTF-16 LE
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* @len: length of the return packet
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*
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* Produces either a manufacturer, product or serial number string for the
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* virtual root hub device.
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*/
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static int rh_string (
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int id,
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struct usb_hcd *hcd,
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u8 *data,
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int len
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) {
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char buf [100];
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// language ids
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if (id == 0) {
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buf[0] = 4; buf[1] = 3; /* 4 bytes string data */
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buf[2] = 0x09; buf[3] = 0x04; /* MSFT-speak for "en-us" */
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len = min (len, 4);
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memcpy (data, buf, len);
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return len;
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// serial number
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} else if (id == 1) {
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strlcpy (buf, hcd->self.bus_name, sizeof buf);
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// product description
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} else if (id == 2) {
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strlcpy (buf, hcd->product_desc, sizeof buf);
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// id 3 == vendor description
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} else if (id == 3) {
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snprintf (buf, sizeof buf, "%s %s %s", init_utsname()->sysname,
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init_utsname()->release, hcd->driver->description);
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// unsupported IDs --> "protocol stall"
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} else
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return -EPIPE;
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switch (len) { /* All cases fall through */
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default:
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len = 2 + ascii2utf (buf, data + 2, len - 2);
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case 2:
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data [1] = 3; /* type == string */
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case 1:
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data [0] = 2 * (strlen (buf) + 1);
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case 0:
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; /* Compiler wants a statement here */
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}
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return len;
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}
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/* Root hub control transfers execute synchronously */
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static int rh_call_control (struct usb_hcd *hcd, struct urb *urb)
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{
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struct usb_ctrlrequest *cmd;
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u16 typeReq, wValue, wIndex, wLength;
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u8 *ubuf = urb->transfer_buffer;
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u8 tbuf [sizeof (struct usb_hub_descriptor)]
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__attribute__((aligned(4)));
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const u8 *bufp = tbuf;
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int len = 0;
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int patch_wakeup = 0;
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unsigned long flags;
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int status = 0;
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int n;
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cmd = (struct usb_ctrlrequest *) urb->setup_packet;
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typeReq = (cmd->bRequestType << 8) | cmd->bRequest;
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wValue = le16_to_cpu (cmd->wValue);
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wIndex = le16_to_cpu (cmd->wIndex);
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wLength = le16_to_cpu (cmd->wLength);
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if (wLength > urb->transfer_buffer_length)
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goto error;
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urb->actual_length = 0;
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switch (typeReq) {
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/* DEVICE REQUESTS */
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/* The root hub's remote wakeup enable bit is implemented using
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* driver model wakeup flags. If this system supports wakeup
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* through USB, userspace may change the default "allow wakeup"
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* policy through sysfs or these calls.
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*
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* Most root hubs support wakeup from downstream devices, for
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* runtime power management (disabling USB clocks and reducing
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* VBUS power usage). However, not all of them do so; silicon,
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* board, and BIOS bugs here are not uncommon, so these can't
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* be treated quite like external hubs.
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*
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* Likewise, not all root hubs will pass wakeup events upstream,
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* to wake up the whole system. So don't assume root hub and
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* controller capabilities are identical.
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*/
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case DeviceRequest | USB_REQ_GET_STATUS:
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tbuf [0] = (device_may_wakeup(&hcd->self.root_hub->dev)
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<< USB_DEVICE_REMOTE_WAKEUP)
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| (1 << USB_DEVICE_SELF_POWERED);
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tbuf [1] = 0;
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len = 2;
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break;
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case DeviceOutRequest | USB_REQ_CLEAR_FEATURE:
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if (wValue == USB_DEVICE_REMOTE_WAKEUP)
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device_set_wakeup_enable(&hcd->self.root_hub->dev, 0);
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else
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goto error;
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break;
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case DeviceOutRequest | USB_REQ_SET_FEATURE:
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if (device_can_wakeup(&hcd->self.root_hub->dev)
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&& wValue == USB_DEVICE_REMOTE_WAKEUP)
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device_set_wakeup_enable(&hcd->self.root_hub->dev, 1);
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else
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goto error;
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break;
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case DeviceRequest | USB_REQ_GET_CONFIGURATION:
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tbuf [0] = 1;
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len = 1;
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/* FALLTHROUGH */
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case DeviceOutRequest | USB_REQ_SET_CONFIGURATION:
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break;
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case DeviceRequest | USB_REQ_GET_DESCRIPTOR:
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switch (wValue & 0xff00) {
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case USB_DT_DEVICE << 8:
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if (hcd->driver->flags & HCD_USB2)
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bufp = usb2_rh_dev_descriptor;
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else if (hcd->driver->flags & HCD_USB11)
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bufp = usb11_rh_dev_descriptor;
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else
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goto error;
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len = 18;
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break;
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case USB_DT_CONFIG << 8:
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if (hcd->driver->flags & HCD_USB2) {
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bufp = hs_rh_config_descriptor;
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len = sizeof hs_rh_config_descriptor;
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} else {
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bufp = fs_rh_config_descriptor;
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len = sizeof fs_rh_config_descriptor;
|
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}
|
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if (device_can_wakeup(&hcd->self.root_hub->dev))
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patch_wakeup = 1;
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break;
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case USB_DT_STRING << 8:
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n = rh_string (wValue & 0xff, hcd, ubuf, wLength);
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if (n < 0)
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goto error;
|
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urb->actual_length = n;
|
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break;
|
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default:
|
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goto error;
|
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}
|
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break;
|
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case DeviceRequest | USB_REQ_GET_INTERFACE:
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tbuf [0] = 0;
|
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len = 1;
|
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/* FALLTHROUGH */
|
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case DeviceOutRequest | USB_REQ_SET_INTERFACE:
|
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break;
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case DeviceOutRequest | USB_REQ_SET_ADDRESS:
|
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// wValue == urb->dev->devaddr
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dev_dbg (hcd->self.controller, "root hub device address %d\n",
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wValue);
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break;
|
|
|
|
/* INTERFACE REQUESTS (no defined feature/status flags) */
|
|
|
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/* ENDPOINT REQUESTS */
|
|
|
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case EndpointRequest | USB_REQ_GET_STATUS:
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// ENDPOINT_HALT flag
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tbuf [0] = 0;
|
|
tbuf [1] = 0;
|
|
len = 2;
|
|
/* FALLTHROUGH */
|
|
case EndpointOutRequest | USB_REQ_CLEAR_FEATURE:
|
|
case EndpointOutRequest | USB_REQ_SET_FEATURE:
|
|
dev_dbg (hcd->self.controller, "no endpoint features yet\n");
|
|
break;
|
|
|
|
/* CLASS REQUESTS (and errors) */
|
|
|
|
default:
|
|
/* non-generic request */
|
|
switch (typeReq) {
|
|
case GetHubStatus:
|
|
case GetPortStatus:
|
|
len = 4;
|
|
break;
|
|
case GetHubDescriptor:
|
|
len = sizeof (struct usb_hub_descriptor);
|
|
break;
|
|
}
|
|
status = hcd->driver->hub_control (hcd,
|
|
typeReq, wValue, wIndex,
|
|
tbuf, wLength);
|
|
break;
|
|
error:
|
|
/* "protocol stall" on error */
|
|
status = -EPIPE;
|
|
}
|
|
|
|
if (status) {
|
|
len = 0;
|
|
if (status != -EPIPE) {
|
|
dev_dbg (hcd->self.controller,
|
|
"CTRL: TypeReq=0x%x val=0x%x "
|
|
"idx=0x%x len=%d ==> %d\n",
|
|
typeReq, wValue, wIndex,
|
|
wLength, status);
|
|
}
|
|
}
|
|
if (len) {
|
|
if (urb->transfer_buffer_length < len)
|
|
len = urb->transfer_buffer_length;
|
|
urb->actual_length = len;
|
|
// always USB_DIR_IN, toward host
|
|
memcpy (ubuf, bufp, len);
|
|
|
|
/* report whether RH hardware supports remote wakeup */
|
|
if (patch_wakeup &&
|
|
len > offsetof (struct usb_config_descriptor,
|
|
bmAttributes))
|
|
((struct usb_config_descriptor *)ubuf)->bmAttributes
|
|
|= USB_CONFIG_ATT_WAKEUP;
|
|
}
|
|
|
|
/* any errors get returned through the urb completion */
|
|
local_irq_save (flags);
|
|
spin_lock (&urb->lock);
|
|
if (urb->status == -EINPROGRESS)
|
|
urb->status = status;
|
|
spin_unlock (&urb->lock);
|
|
usb_hcd_giveback_urb (hcd, urb);
|
|
local_irq_restore (flags);
|
|
return 0;
|
|
}
|
|
|
|
/*-------------------------------------------------------------------------*/
|
|
|
|
/*
|
|
* Root Hub interrupt transfers are polled using a timer if the
|
|
* driver requests it; otherwise the driver is responsible for
|
|
* calling usb_hcd_poll_rh_status() when an event occurs.
|
|
*
|
|
* Completions are called in_interrupt(), but they may or may not
|
|
* be in_irq().
|
|
*/
|
|
void usb_hcd_poll_rh_status(struct usb_hcd *hcd)
|
|
{
|
|
struct urb *urb;
|
|
int length;
|
|
unsigned long flags;
|
|
char buffer[4]; /* Any root hubs with > 31 ports? */
|
|
|
|
if (unlikely(!hcd->rh_registered))
|
|
return;
|
|
if (!hcd->uses_new_polling && !hcd->status_urb)
|
|
return;
|
|
|
|
length = hcd->driver->hub_status_data(hcd, buffer);
|
|
if (length > 0) {
|
|
|
|
/* try to complete the status urb */
|
|
local_irq_save (flags);
|
|
spin_lock(&hcd_root_hub_lock);
|
|
urb = hcd->status_urb;
|
|
if (urb) {
|
|
spin_lock(&urb->lock);
|
|
if (urb->status == -EINPROGRESS) {
|
|
hcd->poll_pending = 0;
|
|
hcd->status_urb = NULL;
|
|
urb->status = 0;
|
|
urb->hcpriv = NULL;
|
|
urb->actual_length = length;
|
|
memcpy(urb->transfer_buffer, buffer, length);
|
|
} else /* urb has been unlinked */
|
|
length = 0;
|
|
spin_unlock(&urb->lock);
|
|
} else
|
|
length = 0;
|
|
spin_unlock(&hcd_root_hub_lock);
|
|
|
|
/* local irqs are always blocked in completions */
|
|
if (length > 0)
|
|
usb_hcd_giveback_urb (hcd, urb);
|
|
else
|
|
hcd->poll_pending = 1;
|
|
local_irq_restore (flags);
|
|
}
|
|
|
|
/* The USB 2.0 spec says 256 ms. This is close enough and won't
|
|
* exceed that limit if HZ is 100. */
|
|
if (hcd->uses_new_polling ? hcd->poll_rh :
|
|
(length == 0 && hcd->status_urb != NULL))
|
|
mod_timer (&hcd->rh_timer, jiffies + msecs_to_jiffies(250));
|
|
}
|
|
EXPORT_SYMBOL_GPL(usb_hcd_poll_rh_status);
|
|
|
|
/* timer callback */
|
|
static void rh_timer_func (unsigned long _hcd)
|
|
{
|
|
usb_hcd_poll_rh_status((struct usb_hcd *) _hcd);
|
|
}
|
|
|
|
/*-------------------------------------------------------------------------*/
|
|
|
|
static int rh_queue_status (struct usb_hcd *hcd, struct urb *urb)
|
|
{
|
|
int retval;
|
|
unsigned long flags;
|
|
int len = 1 + (urb->dev->maxchild / 8);
|
|
|
|
spin_lock_irqsave (&hcd_root_hub_lock, flags);
|
|
if (urb->status != -EINPROGRESS) /* already unlinked */
|
|
retval = urb->status;
|
|
else if (hcd->status_urb || urb->transfer_buffer_length < len) {
|
|
dev_dbg (hcd->self.controller, "not queuing rh status urb\n");
|
|
retval = -EINVAL;
|
|
} else {
|
|
hcd->status_urb = urb;
|
|
urb->hcpriv = hcd; /* indicate it's queued */
|
|
|
|
if (!hcd->uses_new_polling)
|
|
mod_timer (&hcd->rh_timer, jiffies +
|
|
msecs_to_jiffies(250));
|
|
|
|
/* If a status change has already occurred, report it ASAP */
|
|
else if (hcd->poll_pending)
|
|
mod_timer (&hcd->rh_timer, jiffies);
|
|
retval = 0;
|
|
}
|
|
spin_unlock_irqrestore (&hcd_root_hub_lock, flags);
|
|
return retval;
|
|
}
|
|
|
|
static int rh_urb_enqueue (struct usb_hcd *hcd, struct urb *urb)
|
|
{
|
|
if (usb_pipeint (urb->pipe))
|
|
return rh_queue_status (hcd, urb);
|
|
if (usb_pipecontrol (urb->pipe))
|
|
return rh_call_control (hcd, urb);
|
|
return -EINVAL;
|
|
}
|
|
|
|
/*-------------------------------------------------------------------------*/
|
|
|
|
/* Unlinks of root-hub control URBs are legal, but they don't do anything
|
|
* since these URBs always execute synchronously.
|
|
*/
|
|
static int usb_rh_urb_dequeue (struct usb_hcd *hcd, struct urb *urb)
|
|
{
|
|
unsigned long flags;
|
|
|
|
if (usb_pipeendpoint(urb->pipe) == 0) { /* Control URB */
|
|
; /* Do nothing */
|
|
|
|
} else { /* Status URB */
|
|
if (!hcd->uses_new_polling)
|
|
del_timer (&hcd->rh_timer);
|
|
local_irq_save (flags);
|
|
spin_lock (&hcd_root_hub_lock);
|
|
if (urb == hcd->status_urb) {
|
|
hcd->status_urb = NULL;
|
|
urb->hcpriv = NULL;
|
|
} else
|
|
urb = NULL; /* wasn't fully queued */
|
|
spin_unlock (&hcd_root_hub_lock);
|
|
if (urb)
|
|
usb_hcd_giveback_urb (hcd, urb);
|
|
local_irq_restore (flags);
|
|
}
|
|
|
|
return 0;
|
|
}
|
|
|
|
/*-------------------------------------------------------------------------*/
|
|
|
|
static struct class *usb_host_class;
|
|
|
|
int usb_host_init(void)
|
|
{
|
|
int retval = 0;
|
|
|
|
usb_host_class = class_create(THIS_MODULE, "usb_host");
|
|
if (IS_ERR(usb_host_class))
|
|
retval = PTR_ERR(usb_host_class);
|
|
return retval;
|
|
}
|
|
|
|
void usb_host_cleanup(void)
|
|
{
|
|
class_destroy(usb_host_class);
|
|
}
|
|
|
|
/**
|
|
* usb_bus_init - shared initialization code
|
|
* @bus: the bus structure being initialized
|
|
*
|
|
* This code is used to initialize a usb_bus structure, memory for which is
|
|
* separately managed.
|
|
*/
|
|
static void usb_bus_init (struct usb_bus *bus)
|
|
{
|
|
memset (&bus->devmap, 0, sizeof(struct usb_devmap));
|
|
|
|
bus->devnum_next = 1;
|
|
|
|
bus->root_hub = NULL;
|
|
bus->busnum = -1;
|
|
bus->bandwidth_allocated = 0;
|
|
bus->bandwidth_int_reqs = 0;
|
|
bus->bandwidth_isoc_reqs = 0;
|
|
|
|
INIT_LIST_HEAD (&bus->bus_list);
|
|
}
|
|
|
|
/*-------------------------------------------------------------------------*/
|
|
|
|
/**
|
|
* usb_register_bus - registers the USB host controller with the usb core
|
|
* @bus: pointer to the bus to register
|
|
* Context: !in_interrupt()
|
|
*
|
|
* Assigns a bus number, and links the controller into usbcore data
|
|
* structures so that it can be seen by scanning the bus list.
|
|
*/
|
|
static int usb_register_bus(struct usb_bus *bus)
|
|
{
|
|
int busnum;
|
|
|
|
mutex_lock(&usb_bus_list_lock);
|
|
busnum = find_next_zero_bit (busmap.busmap, USB_MAXBUS, 1);
|
|
if (busnum < USB_MAXBUS) {
|
|
set_bit (busnum, busmap.busmap);
|
|
bus->busnum = busnum;
|
|
} else {
|
|
printk (KERN_ERR "%s: too many buses\n", usbcore_name);
|
|
mutex_unlock(&usb_bus_list_lock);
|
|
return -E2BIG;
|
|
}
|
|
|
|
bus->class_dev = class_device_create(usb_host_class, NULL, MKDEV(0,0),
|
|
bus->controller, "usb_host%d", busnum);
|
|
if (IS_ERR(bus->class_dev)) {
|
|
clear_bit(busnum, busmap.busmap);
|
|
mutex_unlock(&usb_bus_list_lock);
|
|
return PTR_ERR(bus->class_dev);
|
|
}
|
|
|
|
class_set_devdata(bus->class_dev, bus);
|
|
|
|
/* Add it to the local list of buses */
|
|
list_add (&bus->bus_list, &usb_bus_list);
|
|
mutex_unlock(&usb_bus_list_lock);
|
|
|
|
usb_notify_add_bus(bus);
|
|
|
|
dev_info (bus->controller, "new USB bus registered, assigned bus number %d\n", bus->busnum);
|
|
return 0;
|
|
}
|
|
|
|
/**
|
|
* usb_deregister_bus - deregisters the USB host controller
|
|
* @bus: pointer to the bus to deregister
|
|
* Context: !in_interrupt()
|
|
*
|
|
* Recycles the bus number, and unlinks the controller from usbcore data
|
|
* structures so that it won't be seen by scanning the bus list.
|
|
*/
|
|
static void usb_deregister_bus (struct usb_bus *bus)
|
|
{
|
|
dev_info (bus->controller, "USB bus %d deregistered\n", bus->busnum);
|
|
|
|
/*
|
|
* NOTE: make sure that all the devices are removed by the
|
|
* controller code, as well as having it call this when cleaning
|
|
* itself up
|
|
*/
|
|
mutex_lock(&usb_bus_list_lock);
|
|
list_del (&bus->bus_list);
|
|
mutex_unlock(&usb_bus_list_lock);
|
|
|
|
usb_notify_remove_bus(bus);
|
|
|
|
clear_bit (bus->busnum, busmap.busmap);
|
|
|
|
class_device_unregister(bus->class_dev);
|
|
}
|
|
|
|
/**
|
|
* register_root_hub - called by usb_add_hcd() to register a root hub
|
|
* @hcd: host controller for this root hub
|
|
*
|
|
* This function registers the root hub with the USB subsystem. It sets up
|
|
* the device properly in the device tree and then calls usb_new_device()
|
|
* to register the usb device. It also assigns the root hub's USB address
|
|
* (always 1).
|
|
*/
|
|
static int register_root_hub(struct usb_hcd *hcd)
|
|
{
|
|
struct device *parent_dev = hcd->self.controller;
|
|
struct usb_device *usb_dev = hcd->self.root_hub;
|
|
const int devnum = 1;
|
|
int retval;
|
|
|
|
usb_dev->devnum = devnum;
|
|
usb_dev->bus->devnum_next = devnum + 1;
|
|
memset (&usb_dev->bus->devmap.devicemap, 0,
|
|
sizeof usb_dev->bus->devmap.devicemap);
|
|
set_bit (devnum, usb_dev->bus->devmap.devicemap);
|
|
usb_set_device_state(usb_dev, USB_STATE_ADDRESS);
|
|
|
|
mutex_lock(&usb_bus_list_lock);
|
|
|
|
usb_dev->ep0.desc.wMaxPacketSize = __constant_cpu_to_le16(64);
|
|
retval = usb_get_device_descriptor(usb_dev, USB_DT_DEVICE_SIZE);
|
|
if (retval != sizeof usb_dev->descriptor) {
|
|
mutex_unlock(&usb_bus_list_lock);
|
|
dev_dbg (parent_dev, "can't read %s device descriptor %d\n",
|
|
usb_dev->dev.bus_id, retval);
|
|
return (retval < 0) ? retval : -EMSGSIZE;
|
|
}
|
|
|
|
retval = usb_new_device (usb_dev);
|
|
if (retval) {
|
|
dev_err (parent_dev, "can't register root hub for %s, %d\n",
|
|
usb_dev->dev.bus_id, retval);
|
|
}
|
|
mutex_unlock(&usb_bus_list_lock);
|
|
|
|
if (retval == 0) {
|
|
spin_lock_irq (&hcd_root_hub_lock);
|
|
hcd->rh_registered = 1;
|
|
spin_unlock_irq (&hcd_root_hub_lock);
|
|
|
|
/* Did the HC die before the root hub was registered? */
|
|
if (hcd->state == HC_STATE_HALT)
|
|
usb_hc_died (hcd); /* This time clean up */
|
|
}
|
|
|
|
return retval;
|
|
}
|
|
|
|
void usb_enable_root_hub_irq (struct usb_bus *bus)
|
|
{
|
|
struct usb_hcd *hcd;
|
|
|
|
hcd = container_of (bus, struct usb_hcd, self);
|
|
if (hcd->driver->hub_irq_enable && hcd->state != HC_STATE_HALT)
|
|
hcd->driver->hub_irq_enable (hcd);
|
|
}
|
|
|
|
|
|
/*-------------------------------------------------------------------------*/
|
|
|
|
/**
|
|
* usb_calc_bus_time - approximate periodic transaction time in nanoseconds
|
|
* @speed: from dev->speed; USB_SPEED_{LOW,FULL,HIGH}
|
|
* @is_input: true iff the transaction sends data to the host
|
|
* @isoc: true for isochronous transactions, false for interrupt ones
|
|
* @bytecount: how many bytes in the transaction.
|
|
*
|
|
* Returns approximate bus time in nanoseconds for a periodic transaction.
|
|
* See USB 2.0 spec section 5.11.3; only periodic transfers need to be
|
|
* scheduled in software, this function is only used for such scheduling.
|
|
*/
|
|
long usb_calc_bus_time (int speed, int is_input, int isoc, int bytecount)
|
|
{
|
|
unsigned long tmp;
|
|
|
|
switch (speed) {
|
|
case USB_SPEED_LOW: /* INTR only */
|
|
if (is_input) {
|
|
tmp = (67667L * (31L + 10L * BitTime (bytecount))) / 1000L;
|
|
return (64060L + (2 * BW_HUB_LS_SETUP) + BW_HOST_DELAY + tmp);
|
|
} else {
|
|
tmp = (66700L * (31L + 10L * BitTime (bytecount))) / 1000L;
|
|
return (64107L + (2 * BW_HUB_LS_SETUP) + BW_HOST_DELAY + tmp);
|
|
}
|
|
case USB_SPEED_FULL: /* ISOC or INTR */
|
|
if (isoc) {
|
|
tmp = (8354L * (31L + 10L * BitTime (bytecount))) / 1000L;
|
|
return (((is_input) ? 7268L : 6265L) + BW_HOST_DELAY + tmp);
|
|
} else {
|
|
tmp = (8354L * (31L + 10L * BitTime (bytecount))) / 1000L;
|
|
return (9107L + BW_HOST_DELAY + tmp);
|
|
}
|
|
case USB_SPEED_HIGH: /* ISOC or INTR */
|
|
// FIXME adjust for input vs output
|
|
if (isoc)
|
|
tmp = HS_NSECS_ISO (bytecount);
|
|
else
|
|
tmp = HS_NSECS (bytecount);
|
|
return tmp;
|
|
default:
|
|
pr_debug ("%s: bogus device speed!\n", usbcore_name);
|
|
return -1;
|
|
}
|
|
}
|
|
EXPORT_SYMBOL (usb_calc_bus_time);
|
|
|
|
|
|
/*-------------------------------------------------------------------------*/
|
|
|
|
/*
|
|
* Generic HC operations.
|
|
*/
|
|
|
|
/*-------------------------------------------------------------------------*/
|
|
|
|
static void urb_unlink (struct urb *urb)
|
|
{
|
|
unsigned long flags;
|
|
|
|
/* clear all state linking urb to this dev (and hcd) */
|
|
|
|
spin_lock_irqsave (&hcd_data_lock, flags);
|
|
list_del_init (&urb->urb_list);
|
|
spin_unlock_irqrestore (&hcd_data_lock, flags);
|
|
}
|
|
|
|
|
|
/* may be called in any context with a valid urb->dev usecount
|
|
* caller surrenders "ownership" of urb
|
|
* expects usb_submit_urb() to have sanity checked and conditioned all
|
|
* inputs in the urb
|
|
*/
|
|
int usb_hcd_submit_urb (struct urb *urb, gfp_t mem_flags)
|
|
{
|
|
int status;
|
|
struct usb_hcd *hcd = bus_to_hcd(urb->dev->bus);
|
|
struct usb_host_endpoint *ep;
|
|
unsigned long flags;
|
|
|
|
if (!hcd)
|
|
return -ENODEV;
|
|
|
|
usbmon_urb_submit(&hcd->self, urb);
|
|
|
|
/*
|
|
* Atomically queue the urb, first to our records, then to the HCD.
|
|
* Access to urb->status is controlled by urb->lock ... changes on
|
|
* i/o completion (normal or fault) or unlinking.
|
|
*/
|
|
|
|
// FIXME: verify that quiescing hc works right (RH cleans up)
|
|
|
|
spin_lock_irqsave (&hcd_data_lock, flags);
|
|
ep = (usb_pipein(urb->pipe) ? urb->dev->ep_in : urb->dev->ep_out)
|
|
[usb_pipeendpoint(urb->pipe)];
|
|
if (unlikely (!ep))
|
|
status = -ENOENT;
|
|
else if (unlikely (urb->reject))
|
|
status = -EPERM;
|
|
else switch (hcd->state) {
|
|
case HC_STATE_RUNNING:
|
|
case HC_STATE_RESUMING:
|
|
doit:
|
|
list_add_tail (&urb->urb_list, &ep->urb_list);
|
|
status = 0;
|
|
break;
|
|
case HC_STATE_SUSPENDED:
|
|
/* HC upstream links (register access, wakeup signaling) can work
|
|
* even when the downstream links (and DMA etc) are quiesced; let
|
|
* usbcore talk to the root hub.
|
|
*/
|
|
if (hcd->self.controller->power.power_state.event == PM_EVENT_ON
|
|
&& urb->dev->parent == NULL)
|
|
goto doit;
|
|
/* FALL THROUGH */
|
|
default:
|
|
status = -ESHUTDOWN;
|
|
break;
|
|
}
|
|
spin_unlock_irqrestore (&hcd_data_lock, flags);
|
|
if (status) {
|
|
INIT_LIST_HEAD (&urb->urb_list);
|
|
usbmon_urb_submit_error(&hcd->self, urb, status);
|
|
return status;
|
|
}
|
|
|
|
/* increment urb's reference count as part of giving it to the HCD
|
|
* (which now controls it). HCD guarantees that it either returns
|
|
* an error or calls giveback(), but not both.
|
|
*/
|
|
urb = usb_get_urb (urb);
|
|
atomic_inc (&urb->use_count);
|
|
|
|
if (urb->dev == hcd->self.root_hub) {
|
|
/* NOTE: requirement on hub callers (usbfs and the hub
|
|
* driver, for now) that URBs' urb->transfer_buffer be
|
|
* valid and usb_buffer_{sync,unmap}() not be needed, since
|
|
* they could clobber root hub response data.
|
|
*/
|
|
status = rh_urb_enqueue (hcd, urb);
|
|
goto done;
|
|
}
|
|
|
|
/* lower level hcd code should use *_dma exclusively,
|
|
* unless it uses pio or talks to another transport.
|
|
*/
|
|
if (hcd->self.uses_dma) {
|
|
if (usb_pipecontrol (urb->pipe)
|
|
&& !(urb->transfer_flags & URB_NO_SETUP_DMA_MAP))
|
|
urb->setup_dma = dma_map_single (
|
|
hcd->self.controller,
|
|
urb->setup_packet,
|
|
sizeof (struct usb_ctrlrequest),
|
|
DMA_TO_DEVICE);
|
|
if (urb->transfer_buffer_length != 0
|
|
&& !(urb->transfer_flags & URB_NO_TRANSFER_DMA_MAP))
|
|
urb->transfer_dma = dma_map_single (
|
|
hcd->self.controller,
|
|
urb->transfer_buffer,
|
|
urb->transfer_buffer_length,
|
|
usb_pipein (urb->pipe)
|
|
? DMA_FROM_DEVICE
|
|
: DMA_TO_DEVICE);
|
|
}
|
|
|
|
status = hcd->driver->urb_enqueue (hcd, ep, urb, mem_flags);
|
|
done:
|
|
if (unlikely (status)) {
|
|
urb_unlink (urb);
|
|
atomic_dec (&urb->use_count);
|
|
if (urb->reject)
|
|
wake_up (&usb_kill_urb_queue);
|
|
usb_put_urb (urb);
|
|
usbmon_urb_submit_error(&hcd->self, urb, status);
|
|
}
|
|
return status;
|
|
}
|
|
|
|
/*-------------------------------------------------------------------------*/
|
|
|
|
/* called in any context */
|
|
int usb_hcd_get_frame_number (struct usb_device *udev)
|
|
{
|
|
struct usb_hcd *hcd = bus_to_hcd(udev->bus);
|
|
|
|
if (!HC_IS_RUNNING (hcd->state))
|
|
return -ESHUTDOWN;
|
|
return hcd->driver->get_frame_number (hcd);
|
|
}
|
|
|
|
/*-------------------------------------------------------------------------*/
|
|
|
|
/* this makes the hcd giveback() the urb more quickly, by kicking it
|
|
* off hardware queues (which may take a while) and returning it as
|
|
* soon as practical. we've already set up the urb's return status,
|
|
* but we can't know if the callback completed already.
|
|
*/
|
|
static int
|
|
unlink1 (struct usb_hcd *hcd, struct urb *urb)
|
|
{
|
|
int value;
|
|
|
|
if (urb->dev == hcd->self.root_hub)
|
|
value = usb_rh_urb_dequeue (hcd, urb);
|
|
else {
|
|
|
|
/* The only reason an HCD might fail this call is if
|
|
* it has not yet fully queued the urb to begin with.
|
|
* Such failures should be harmless. */
|
|
value = hcd->driver->urb_dequeue (hcd, urb);
|
|
}
|
|
|
|
if (value != 0)
|
|
dev_dbg (hcd->self.controller, "dequeue %p --> %d\n",
|
|
urb, value);
|
|
return value;
|
|
}
|
|
|
|
/*
|
|
* called in any context
|
|
*
|
|
* caller guarantees urb won't be recycled till both unlink()
|
|
* and the urb's completion function return
|
|
*/
|
|
int usb_hcd_unlink_urb (struct urb *urb, int status)
|
|
{
|
|
struct usb_host_endpoint *ep;
|
|
struct usb_hcd *hcd = NULL;
|
|
struct device *sys = NULL;
|
|
unsigned long flags;
|
|
struct list_head *tmp;
|
|
int retval;
|
|
|
|
if (!urb)
|
|
return -EINVAL;
|
|
if (!urb->dev || !urb->dev->bus)
|
|
return -ENODEV;
|
|
ep = (usb_pipein(urb->pipe) ? urb->dev->ep_in : urb->dev->ep_out)
|
|
[usb_pipeendpoint(urb->pipe)];
|
|
if (!ep)
|
|
return -ENODEV;
|
|
|
|
/*
|
|
* we contend for urb->status with the hcd core,
|
|
* which changes it while returning the urb.
|
|
*
|
|
* Caller guaranteed that the urb pointer hasn't been freed, and
|
|
* that it was submitted. But as a rule it can't know whether or
|
|
* not it's already been unlinked ... so we respect the reversed
|
|
* lock sequence needed for the usb_hcd_giveback_urb() code paths
|
|
* (urb lock, then hcd_data_lock) in case some other CPU is now
|
|
* unlinking it.
|
|
*/
|
|
spin_lock_irqsave (&urb->lock, flags);
|
|
spin_lock (&hcd_data_lock);
|
|
|
|
sys = &urb->dev->dev;
|
|
hcd = bus_to_hcd(urb->dev->bus);
|
|
if (hcd == NULL) {
|
|
retval = -ENODEV;
|
|
goto done;
|
|
}
|
|
|
|
/* insist the urb is still queued */
|
|
list_for_each(tmp, &ep->urb_list) {
|
|
if (tmp == &urb->urb_list)
|
|
break;
|
|
}
|
|
if (tmp != &urb->urb_list) {
|
|
retval = -EIDRM;
|
|
goto done;
|
|
}
|
|
|
|
/* Any status except -EINPROGRESS means something already started to
|
|
* unlink this URB from the hardware. So there's no more work to do.
|
|
*/
|
|
if (urb->status != -EINPROGRESS) {
|
|
retval = -EBUSY;
|
|
goto done;
|
|
}
|
|
|
|
/* IRQ setup can easily be broken so that USB controllers
|
|
* never get completion IRQs ... maybe even the ones we need to
|
|
* finish unlinking the initial failed usb_set_address()
|
|
* or device descriptor fetch.
|
|
*/
|
|
if (!test_bit(HCD_FLAG_SAW_IRQ, &hcd->flags)
|
|
&& hcd->self.root_hub != urb->dev) {
|
|
dev_warn (hcd->self.controller, "Unlink after no-IRQ? "
|
|
"Controller is probably using the wrong IRQ."
|
|
"\n");
|
|
set_bit(HCD_FLAG_SAW_IRQ, &hcd->flags);
|
|
}
|
|
|
|
urb->status = status;
|
|
|
|
spin_unlock (&hcd_data_lock);
|
|
spin_unlock_irqrestore (&urb->lock, flags);
|
|
|
|
retval = unlink1 (hcd, urb);
|
|
if (retval == 0)
|
|
retval = -EINPROGRESS;
|
|
return retval;
|
|
|
|
done:
|
|
spin_unlock (&hcd_data_lock);
|
|
spin_unlock_irqrestore (&urb->lock, flags);
|
|
if (retval != -EIDRM && sys && sys->driver)
|
|
dev_dbg (sys, "hcd_unlink_urb %p fail %d\n", urb, retval);
|
|
return retval;
|
|
}
|
|
|
|
/*-------------------------------------------------------------------------*/
|
|
|
|
/* disables the endpoint: cancels any pending urbs, then synchronizes with
|
|
* the hcd to make sure all endpoint state is gone from hardware, and then
|
|
* waits until the endpoint's queue is completely drained. use for
|
|
* set_configuration, set_interface, driver removal, physical disconnect.
|
|
*
|
|
* example: a qh stored in ep->hcpriv, holding state related to endpoint
|
|
* type, maxpacket size, toggle, halt status, and scheduling.
|
|
*/
|
|
void usb_hcd_endpoint_disable (struct usb_device *udev,
|
|
struct usb_host_endpoint *ep)
|
|
{
|
|
struct usb_hcd *hcd;
|
|
struct urb *urb;
|
|
|
|
hcd = bus_to_hcd(udev->bus);
|
|
|
|
WARN_ON (!HC_IS_RUNNING (hcd->state) && hcd->state != HC_STATE_HALT &&
|
|
udev->state != USB_STATE_NOTATTACHED);
|
|
|
|
local_irq_disable ();
|
|
|
|
/* ep is already gone from udev->ep_{in,out}[]; no more submits */
|
|
rescan:
|
|
spin_lock (&hcd_data_lock);
|
|
list_for_each_entry (urb, &ep->urb_list, urb_list) {
|
|
int tmp;
|
|
|
|
/* the urb may already have been unlinked */
|
|
if (urb->status != -EINPROGRESS)
|
|
continue;
|
|
usb_get_urb (urb);
|
|
spin_unlock (&hcd_data_lock);
|
|
|
|
spin_lock (&urb->lock);
|
|
tmp = urb->status;
|
|
if (tmp == -EINPROGRESS)
|
|
urb->status = -ESHUTDOWN;
|
|
spin_unlock (&urb->lock);
|
|
|
|
/* kick hcd unless it's already returning this */
|
|
if (tmp == -EINPROGRESS) {
|
|
tmp = urb->pipe;
|
|
unlink1 (hcd, urb);
|
|
dev_dbg (hcd->self.controller,
|
|
"shutdown urb %p pipe %08x ep%d%s%s\n",
|
|
urb, tmp, usb_pipeendpoint (tmp),
|
|
(tmp & USB_DIR_IN) ? "in" : "out",
|
|
({ char *s; \
|
|
switch (usb_pipetype (tmp)) { \
|
|
case PIPE_CONTROL: s = ""; break; \
|
|
case PIPE_BULK: s = "-bulk"; break; \
|
|
case PIPE_INTERRUPT: s = "-intr"; break; \
|
|
default: s = "-iso"; break; \
|
|
}; s;}));
|
|
}
|
|
usb_put_urb (urb);
|
|
|
|
/* list contents may have changed */
|
|
goto rescan;
|
|
}
|
|
spin_unlock (&hcd_data_lock);
|
|
local_irq_enable ();
|
|
|
|
/* synchronize with the hardware, so old configuration state
|
|
* clears out immediately (and will be freed).
|
|
*/
|
|
might_sleep ();
|
|
if (hcd->driver->endpoint_disable)
|
|
hcd->driver->endpoint_disable (hcd, ep);
|
|
|
|
/* Wait until the endpoint queue is completely empty. Most HCDs
|
|
* will have done this already in their endpoint_disable method,
|
|
* but some might not. And there could be root-hub control URBs
|
|
* still pending since they aren't affected by the HCDs'
|
|
* endpoint_disable methods.
|
|
*/
|
|
while (!list_empty (&ep->urb_list)) {
|
|
spin_lock_irq (&hcd_data_lock);
|
|
|
|
/* The list may have changed while we acquired the spinlock */
|
|
urb = NULL;
|
|
if (!list_empty (&ep->urb_list)) {
|
|
urb = list_entry (ep->urb_list.prev, struct urb,
|
|
urb_list);
|
|
usb_get_urb (urb);
|
|
}
|
|
spin_unlock_irq (&hcd_data_lock);
|
|
|
|
if (urb) {
|
|
usb_kill_urb (urb);
|
|
usb_put_urb (urb);
|
|
}
|
|
}
|
|
}
|
|
|
|
/*-------------------------------------------------------------------------*/
|
|
|
|
#ifdef CONFIG_PM
|
|
|
|
int hcd_bus_suspend (struct usb_bus *bus)
|
|
{
|
|
struct usb_hcd *hcd;
|
|
int status;
|
|
|
|
hcd = container_of (bus, struct usb_hcd, self);
|
|
if (!hcd->driver->bus_suspend)
|
|
return -ENOENT;
|
|
hcd->state = HC_STATE_QUIESCING;
|
|
status = hcd->driver->bus_suspend (hcd);
|
|
if (status == 0)
|
|
hcd->state = HC_STATE_SUSPENDED;
|
|
else
|
|
dev_dbg(&bus->root_hub->dev, "%s fail, err %d\n",
|
|
"suspend", status);
|
|
return status;
|
|
}
|
|
|
|
int hcd_bus_resume (struct usb_bus *bus)
|
|
{
|
|
struct usb_hcd *hcd;
|
|
int status;
|
|
|
|
hcd = container_of (bus, struct usb_hcd, self);
|
|
if (!hcd->driver->bus_resume)
|
|
return -ENOENT;
|
|
if (hcd->state == HC_STATE_RUNNING)
|
|
return 0;
|
|
hcd->state = HC_STATE_RESUMING;
|
|
status = hcd->driver->bus_resume (hcd);
|
|
if (status == 0)
|
|
hcd->state = HC_STATE_RUNNING;
|
|
else {
|
|
dev_dbg(&bus->root_hub->dev, "%s fail, err %d\n",
|
|
"resume", status);
|
|
usb_hc_died(hcd);
|
|
}
|
|
return status;
|
|
}
|
|
|
|
/* Workqueue routine for root-hub remote wakeup */
|
|
static void hcd_resume_work(struct work_struct *work)
|
|
{
|
|
struct usb_hcd *hcd = container_of(work, struct usb_hcd, wakeup_work);
|
|
struct usb_device *udev = hcd->self.root_hub;
|
|
|
|
usb_lock_device(udev);
|
|
usb_mark_last_busy(udev);
|
|
usb_external_resume_device(udev);
|
|
usb_unlock_device(udev);
|
|
}
|
|
|
|
/**
|
|
* usb_hcd_resume_root_hub - called by HCD to resume its root hub
|
|
* @hcd: host controller for this root hub
|
|
*
|
|
* The USB host controller calls this function when its root hub is
|
|
* suspended (with the remote wakeup feature enabled) and a remote
|
|
* wakeup request is received. The routine submits a workqueue request
|
|
* to resume the root hub (that is, manage its downstream ports again).
|
|
*/
|
|
void usb_hcd_resume_root_hub (struct usb_hcd *hcd)
|
|
{
|
|
unsigned long flags;
|
|
|
|
spin_lock_irqsave (&hcd_root_hub_lock, flags);
|
|
if (hcd->rh_registered)
|
|
queue_work(ksuspend_usb_wq, &hcd->wakeup_work);
|
|
spin_unlock_irqrestore (&hcd_root_hub_lock, flags);
|
|
}
|
|
EXPORT_SYMBOL_GPL(usb_hcd_resume_root_hub);
|
|
|
|
#endif
|
|
|
|
/*-------------------------------------------------------------------------*/
|
|
|
|
#ifdef CONFIG_USB_OTG
|
|
|
|
/**
|
|
* usb_bus_start_enum - start immediate enumeration (for OTG)
|
|
* @bus: the bus (must use hcd framework)
|
|
* @port_num: 1-based number of port; usually bus->otg_port
|
|
* Context: in_interrupt()
|
|
*
|
|
* Starts enumeration, with an immediate reset followed later by
|
|
* khubd identifying and possibly configuring the device.
|
|
* This is needed by OTG controller drivers, where it helps meet
|
|
* HNP protocol timing requirements for starting a port reset.
|
|
*/
|
|
int usb_bus_start_enum(struct usb_bus *bus, unsigned port_num)
|
|
{
|
|
struct usb_hcd *hcd;
|
|
int status = -EOPNOTSUPP;
|
|
|
|
/* NOTE: since HNP can't start by grabbing the bus's address0_sem,
|
|
* boards with root hubs hooked up to internal devices (instead of
|
|
* just the OTG port) may need more attention to resetting...
|
|
*/
|
|
hcd = container_of (bus, struct usb_hcd, self);
|
|
if (port_num && hcd->driver->start_port_reset)
|
|
status = hcd->driver->start_port_reset(hcd, port_num);
|
|
|
|
/* run khubd shortly after (first) root port reset finishes;
|
|
* it may issue others, until at least 50 msecs have passed.
|
|
*/
|
|
if (status == 0)
|
|
mod_timer(&hcd->rh_timer, jiffies + msecs_to_jiffies(10));
|
|
return status;
|
|
}
|
|
EXPORT_SYMBOL (usb_bus_start_enum);
|
|
|
|
#endif
|
|
|
|
/*-------------------------------------------------------------------------*/
|
|
|
|
/**
|
|
* usb_hcd_giveback_urb - return URB from HCD to device driver
|
|
* @hcd: host controller returning the URB
|
|
* @urb: urb being returned to the USB device driver.
|
|
* Context: in_interrupt()
|
|
*
|
|
* This hands the URB from HCD to its USB device driver, using its
|
|
* completion function. The HCD has freed all per-urb resources
|
|
* (and is done using urb->hcpriv). It also released all HCD locks;
|
|
* the device driver won't cause problems if it frees, modifies,
|
|
* or resubmits this URB.
|
|
*/
|
|
void usb_hcd_giveback_urb (struct usb_hcd *hcd, struct urb *urb)
|
|
{
|
|
int at_root_hub;
|
|
|
|
at_root_hub = (urb->dev == hcd->self.root_hub);
|
|
urb_unlink (urb);
|
|
|
|
/* lower level hcd code should use *_dma exclusively if the
|
|
* host controller does DMA */
|
|
if (hcd->self.uses_dma && !at_root_hub) {
|
|
if (usb_pipecontrol (urb->pipe)
|
|
&& !(urb->transfer_flags & URB_NO_SETUP_DMA_MAP))
|
|
dma_unmap_single (hcd->self.controller, urb->setup_dma,
|
|
sizeof (struct usb_ctrlrequest),
|
|
DMA_TO_DEVICE);
|
|
if (urb->transfer_buffer_length != 0
|
|
&& !(urb->transfer_flags & URB_NO_TRANSFER_DMA_MAP))
|
|
dma_unmap_single (hcd->self.controller,
|
|
urb->transfer_dma,
|
|
urb->transfer_buffer_length,
|
|
usb_pipein (urb->pipe)
|
|
? DMA_FROM_DEVICE
|
|
: DMA_TO_DEVICE);
|
|
}
|
|
|
|
usbmon_urb_complete (&hcd->self, urb);
|
|
/* pass ownership to the completion handler */
|
|
urb->complete (urb);
|
|
atomic_dec (&urb->use_count);
|
|
if (unlikely (urb->reject))
|
|
wake_up (&usb_kill_urb_queue);
|
|
usb_put_urb (urb);
|
|
}
|
|
EXPORT_SYMBOL (usb_hcd_giveback_urb);
|
|
|
|
/*-------------------------------------------------------------------------*/
|
|
|
|
/**
|
|
* usb_hcd_irq - hook IRQs to HCD framework (bus glue)
|
|
* @irq: the IRQ being raised
|
|
* @__hcd: pointer to the HCD whose IRQ is being signaled
|
|
* @r: saved hardware registers
|
|
*
|
|
* If the controller isn't HALTed, calls the driver's irq handler.
|
|
* Checks whether the controller is now dead.
|
|
*/
|
|
irqreturn_t usb_hcd_irq (int irq, void *__hcd)
|
|
{
|
|
struct usb_hcd *hcd = __hcd;
|
|
int start = hcd->state;
|
|
|
|
if (unlikely(start == HC_STATE_HALT ||
|
|
!test_bit(HCD_FLAG_HW_ACCESSIBLE, &hcd->flags)))
|
|
return IRQ_NONE;
|
|
if (hcd->driver->irq (hcd) == IRQ_NONE)
|
|
return IRQ_NONE;
|
|
|
|
set_bit(HCD_FLAG_SAW_IRQ, &hcd->flags);
|
|
|
|
if (unlikely(hcd->state == HC_STATE_HALT))
|
|
usb_hc_died (hcd);
|
|
return IRQ_HANDLED;
|
|
}
|
|
|
|
/*-------------------------------------------------------------------------*/
|
|
|
|
/**
|
|
* usb_hc_died - report abnormal shutdown of a host controller (bus glue)
|
|
* @hcd: pointer to the HCD representing the controller
|
|
*
|
|
* This is called by bus glue to report a USB host controller that died
|
|
* while operations may still have been pending. It's called automatically
|
|
* by the PCI glue, so only glue for non-PCI busses should need to call it.
|
|
*/
|
|
void usb_hc_died (struct usb_hcd *hcd)
|
|
{
|
|
unsigned long flags;
|
|
|
|
dev_err (hcd->self.controller, "HC died; cleaning up\n");
|
|
|
|
spin_lock_irqsave (&hcd_root_hub_lock, flags);
|
|
if (hcd->rh_registered) {
|
|
hcd->poll_rh = 0;
|
|
|
|
/* make khubd clean up old urbs and devices */
|
|
usb_set_device_state (hcd->self.root_hub,
|
|
USB_STATE_NOTATTACHED);
|
|
usb_kick_khubd (hcd->self.root_hub);
|
|
}
|
|
spin_unlock_irqrestore (&hcd_root_hub_lock, flags);
|
|
}
|
|
EXPORT_SYMBOL_GPL (usb_hc_died);
|
|
|
|
/*-------------------------------------------------------------------------*/
|
|
|
|
/**
|
|
* usb_create_hcd - create and initialize an HCD structure
|
|
* @driver: HC driver that will use this hcd
|
|
* @dev: device for this HC, stored in hcd->self.controller
|
|
* @bus_name: value to store in hcd->self.bus_name
|
|
* Context: !in_interrupt()
|
|
*
|
|
* Allocate a struct usb_hcd, with extra space at the end for the
|
|
* HC driver's private data. Initialize the generic members of the
|
|
* hcd structure.
|
|
*
|
|
* If memory is unavailable, returns NULL.
|
|
*/
|
|
struct usb_hcd *usb_create_hcd (const struct hc_driver *driver,
|
|
struct device *dev, char *bus_name)
|
|
{
|
|
struct usb_hcd *hcd;
|
|
|
|
hcd = kzalloc(sizeof(*hcd) + driver->hcd_priv_size, GFP_KERNEL);
|
|
if (!hcd) {
|
|
dev_dbg (dev, "hcd alloc failed\n");
|
|
return NULL;
|
|
}
|
|
dev_set_drvdata(dev, hcd);
|
|
kref_init(&hcd->kref);
|
|
|
|
usb_bus_init(&hcd->self);
|
|
hcd->self.controller = dev;
|
|
hcd->self.bus_name = bus_name;
|
|
hcd->self.uses_dma = (dev->dma_mask != NULL);
|
|
|
|
init_timer(&hcd->rh_timer);
|
|
hcd->rh_timer.function = rh_timer_func;
|
|
hcd->rh_timer.data = (unsigned long) hcd;
|
|
#ifdef CONFIG_PM
|
|
INIT_WORK(&hcd->wakeup_work, hcd_resume_work);
|
|
#endif
|
|
|
|
hcd->driver = driver;
|
|
hcd->product_desc = (driver->product_desc) ? driver->product_desc :
|
|
"USB Host Controller";
|
|
|
|
return hcd;
|
|
}
|
|
EXPORT_SYMBOL (usb_create_hcd);
|
|
|
|
static void hcd_release (struct kref *kref)
|
|
{
|
|
struct usb_hcd *hcd = container_of (kref, struct usb_hcd, kref);
|
|
|
|
kfree(hcd);
|
|
}
|
|
|
|
struct usb_hcd *usb_get_hcd (struct usb_hcd *hcd)
|
|
{
|
|
if (hcd)
|
|
kref_get (&hcd->kref);
|
|
return hcd;
|
|
}
|
|
EXPORT_SYMBOL (usb_get_hcd);
|
|
|
|
void usb_put_hcd (struct usb_hcd *hcd)
|
|
{
|
|
if (hcd)
|
|
kref_put (&hcd->kref, hcd_release);
|
|
}
|
|
EXPORT_SYMBOL (usb_put_hcd);
|
|
|
|
/**
|
|
* usb_add_hcd - finish generic HCD structure initialization and register
|
|
* @hcd: the usb_hcd structure to initialize
|
|
* @irqnum: Interrupt line to allocate
|
|
* @irqflags: Interrupt type flags
|
|
*
|
|
* Finish the remaining parts of generic HCD initialization: allocate the
|
|
* buffers of consistent memory, register the bus, request the IRQ line,
|
|
* and call the driver's reset() and start() routines.
|
|
*/
|
|
int usb_add_hcd(struct usb_hcd *hcd,
|
|
unsigned int irqnum, unsigned long irqflags)
|
|
{
|
|
int retval;
|
|
struct usb_device *rhdev;
|
|
|
|
dev_info(hcd->self.controller, "%s\n", hcd->product_desc);
|
|
|
|
set_bit(HCD_FLAG_HW_ACCESSIBLE, &hcd->flags);
|
|
|
|
/* HC is in reset state, but accessible. Now do the one-time init,
|
|
* bottom up so that hcds can customize the root hubs before khubd
|
|
* starts talking to them. (Note, bus id is assigned early too.)
|
|
*/
|
|
if ((retval = hcd_buffer_create(hcd)) != 0) {
|
|
dev_dbg(hcd->self.controller, "pool alloc failed\n");
|
|
return retval;
|
|
}
|
|
|
|
if ((retval = usb_register_bus(&hcd->self)) < 0)
|
|
goto err_register_bus;
|
|
|
|
if ((rhdev = usb_alloc_dev(NULL, &hcd->self, 0)) == NULL) {
|
|
dev_err(hcd->self.controller, "unable to allocate root hub\n");
|
|
retval = -ENOMEM;
|
|
goto err_allocate_root_hub;
|
|
}
|
|
rhdev->speed = (hcd->driver->flags & HCD_USB2) ? USB_SPEED_HIGH :
|
|
USB_SPEED_FULL;
|
|
hcd->self.root_hub = rhdev;
|
|
|
|
/* wakeup flag init defaults to "everything works" for root hubs,
|
|
* but drivers can override it in reset() if needed, along with
|
|
* recording the overall controller's system wakeup capability.
|
|
*/
|
|
device_init_wakeup(&rhdev->dev, 1);
|
|
|
|
/* "reset" is misnamed; its role is now one-time init. the controller
|
|
* should already have been reset (and boot firmware kicked off etc).
|
|
*/
|
|
if (hcd->driver->reset && (retval = hcd->driver->reset(hcd)) < 0) {
|
|
dev_err(hcd->self.controller, "can't setup\n");
|
|
goto err_hcd_driver_setup;
|
|
}
|
|
|
|
/* NOTE: root hub and controller capabilities may not be the same */
|
|
if (device_can_wakeup(hcd->self.controller)
|
|
&& device_can_wakeup(&hcd->self.root_hub->dev))
|
|
dev_dbg(hcd->self.controller, "supports USB remote wakeup\n");
|
|
|
|
/* enable irqs just before we start the controller */
|
|
if (hcd->driver->irq) {
|
|
snprintf(hcd->irq_descr, sizeof(hcd->irq_descr), "%s:usb%d",
|
|
hcd->driver->description, hcd->self.busnum);
|
|
if ((retval = request_irq(irqnum, &usb_hcd_irq, irqflags,
|
|
hcd->irq_descr, hcd)) != 0) {
|
|
dev_err(hcd->self.controller,
|
|
"request interrupt %d failed\n", irqnum);
|
|
goto err_request_irq;
|
|
}
|
|
hcd->irq = irqnum;
|
|
dev_info(hcd->self.controller, "irq %d, %s 0x%08llx\n", irqnum,
|
|
(hcd->driver->flags & HCD_MEMORY) ?
|
|
"io mem" : "io base",
|
|
(unsigned long long)hcd->rsrc_start);
|
|
} else {
|
|
hcd->irq = -1;
|
|
if (hcd->rsrc_start)
|
|
dev_info(hcd->self.controller, "%s 0x%08llx\n",
|
|
(hcd->driver->flags & HCD_MEMORY) ?
|
|
"io mem" : "io base",
|
|
(unsigned long long)hcd->rsrc_start);
|
|
}
|
|
|
|
if ((retval = hcd->driver->start(hcd)) < 0) {
|
|
dev_err(hcd->self.controller, "startup error %d\n", retval);
|
|
goto err_hcd_driver_start;
|
|
}
|
|
|
|
/* starting here, usbcore will pay attention to this root hub */
|
|
rhdev->bus_mA = min(500u, hcd->power_budget);
|
|
if ((retval = register_root_hub(hcd)) != 0)
|
|
goto err_register_root_hub;
|
|
|
|
if (hcd->uses_new_polling && hcd->poll_rh)
|
|
usb_hcd_poll_rh_status(hcd);
|
|
return retval;
|
|
|
|
err_register_root_hub:
|
|
hcd->driver->stop(hcd);
|
|
err_hcd_driver_start:
|
|
if (hcd->irq >= 0)
|
|
free_irq(irqnum, hcd);
|
|
err_request_irq:
|
|
err_hcd_driver_setup:
|
|
hcd->self.root_hub = NULL;
|
|
usb_put_dev(rhdev);
|
|
err_allocate_root_hub:
|
|
usb_deregister_bus(&hcd->self);
|
|
err_register_bus:
|
|
hcd_buffer_destroy(hcd);
|
|
return retval;
|
|
}
|
|
EXPORT_SYMBOL (usb_add_hcd);
|
|
|
|
/**
|
|
* usb_remove_hcd - shutdown processing for generic HCDs
|
|
* @hcd: the usb_hcd structure to remove
|
|
* Context: !in_interrupt()
|
|
*
|
|
* Disconnects the root hub, then reverses the effects of usb_add_hcd(),
|
|
* invoking the HCD's stop() method.
|
|
*/
|
|
void usb_remove_hcd(struct usb_hcd *hcd)
|
|
{
|
|
dev_info(hcd->self.controller, "remove, state %x\n", hcd->state);
|
|
|
|
if (HC_IS_RUNNING (hcd->state))
|
|
hcd->state = HC_STATE_QUIESCING;
|
|
|
|
dev_dbg(hcd->self.controller, "roothub graceful disconnect\n");
|
|
spin_lock_irq (&hcd_root_hub_lock);
|
|
hcd->rh_registered = 0;
|
|
spin_unlock_irq (&hcd_root_hub_lock);
|
|
|
|
#ifdef CONFIG_PM
|
|
flush_workqueue(ksuspend_usb_wq);
|
|
#endif
|
|
|
|
mutex_lock(&usb_bus_list_lock);
|
|
usb_disconnect(&hcd->self.root_hub);
|
|
mutex_unlock(&usb_bus_list_lock);
|
|
|
|
hcd->driver->stop(hcd);
|
|
hcd->state = HC_STATE_HALT;
|
|
|
|
hcd->poll_rh = 0;
|
|
del_timer_sync(&hcd->rh_timer);
|
|
|
|
if (hcd->irq >= 0)
|
|
free_irq(hcd->irq, hcd);
|
|
usb_deregister_bus(&hcd->self);
|
|
hcd_buffer_destroy(hcd);
|
|
}
|
|
EXPORT_SYMBOL (usb_remove_hcd);
|
|
|
|
void
|
|
usb_hcd_platform_shutdown(struct platform_device* dev)
|
|
{
|
|
struct usb_hcd *hcd = platform_get_drvdata(dev);
|
|
|
|
if (hcd->driver->shutdown)
|
|
hcd->driver->shutdown(hcd);
|
|
}
|
|
EXPORT_SYMBOL (usb_hcd_platform_shutdown);
|
|
|
|
/*-------------------------------------------------------------------------*/
|
|
|
|
#if defined(CONFIG_USB_MON)
|
|
|
|
struct usb_mon_operations *mon_ops;
|
|
|
|
/*
|
|
* The registration is unlocked.
|
|
* We do it this way because we do not want to lock in hot paths.
|
|
*
|
|
* Notice that the code is minimally error-proof. Because usbmon needs
|
|
* symbols from usbcore, usbcore gets referenced and cannot be unloaded first.
|
|
*/
|
|
|
|
int usb_mon_register (struct usb_mon_operations *ops)
|
|
{
|
|
|
|
if (mon_ops)
|
|
return -EBUSY;
|
|
|
|
mon_ops = ops;
|
|
mb();
|
|
return 0;
|
|
}
|
|
EXPORT_SYMBOL_GPL (usb_mon_register);
|
|
|
|
void usb_mon_deregister (void)
|
|
{
|
|
|
|
if (mon_ops == NULL) {
|
|
printk(KERN_ERR "USB: monitor was not registered\n");
|
|
return;
|
|
}
|
|
mon_ops = NULL;
|
|
mb();
|
|
}
|
|
EXPORT_SYMBOL_GPL (usb_mon_deregister);
|
|
|
|
#endif /* CONFIG_USB_MON */
|