linux/drivers/usb/core/hcd-pci.c

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/*
* (C) Copyright David Brownell 2000-2002
*
* This program is free software; you can redistribute it and/or modify it
* under the terms of the GNU General Public License as published by the
* Free Software Foundation; either version 2 of the License, or (at your
* option) any later version.
*
* This program is distributed in the hope that it will be useful, but
* WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
* or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
* for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software Foundation,
* Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
*/
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/pci.h>
#include <linux/usb.h>
#include <linux/usb/hcd.h>
#include <asm/io.h>
#include <asm/irq.h>
#ifdef CONFIG_PPC_PMAC
#include <asm/machdep.h>
#include <asm/pmac_feature.h>
#include <asm/pci-bridge.h>
#include <asm/prom.h>
#endif
#include "usb.h"
/* PCI-based HCs are common, but plenty of non-PCI HCs are used too */
2010-02-12 11:21:11 +00:00
#ifdef CONFIG_PM_SLEEP
/* Coordinate handoffs between EHCI and companion controllers
* during system resume
*/
static DEFINE_MUTEX(companions_mutex);
#define CL_UHCI PCI_CLASS_SERIAL_USB_UHCI
#define CL_OHCI PCI_CLASS_SERIAL_USB_OHCI
#define CL_EHCI PCI_CLASS_SERIAL_USB_EHCI
enum companion_action {
SET_HS_COMPANION, CLEAR_HS_COMPANION, WAIT_FOR_COMPANIONS
};
static void companion_common(struct pci_dev *pdev, struct usb_hcd *hcd,
enum companion_action action)
{
struct pci_dev *companion;
struct usb_hcd *companion_hcd;
unsigned int slot = PCI_SLOT(pdev->devfn);
/* Iterate through other PCI functions in the same slot.
* If pdev is OHCI or UHCI then we are looking for EHCI, and
* vice versa.
*/
companion = NULL;
for_each_pci_dev(companion) {
2010-02-12 11:21:11 +00:00
if (companion->bus != pdev->bus ||
PCI_SLOT(companion->devfn) != slot)
continue;
companion_hcd = pci_get_drvdata(companion);
if (!companion_hcd)
continue;
/* For SET_HS_COMPANION, store a pointer to the EHCI bus in
* the OHCI/UHCI companion bus structure.
* For CLEAR_HS_COMPANION, clear the pointer to the EHCI bus
* in the OHCI/UHCI companion bus structure.
* For WAIT_FOR_COMPANIONS, wait until the OHCI/UHCI
* companion controllers have fully resumed.
*/
if ((pdev->class == CL_OHCI || pdev->class == CL_UHCI) &&
companion->class == CL_EHCI) {
/* action must be SET_HS_COMPANION */
dev_dbg(&companion->dev, "HS companion for %s\n",
dev_name(&pdev->dev));
hcd->self.hs_companion = &companion_hcd->self;
} else if (pdev->class == CL_EHCI &&
(companion->class == CL_OHCI ||
companion->class == CL_UHCI)) {
switch (action) {
case SET_HS_COMPANION:
dev_dbg(&pdev->dev, "HS companion for %s\n",
dev_name(&companion->dev));
companion_hcd->self.hs_companion = &hcd->self;
break;
case CLEAR_HS_COMPANION:
companion_hcd->self.hs_companion = NULL;
break;
case WAIT_FOR_COMPANIONS:
device_pm_wait_for_dev(&pdev->dev,
&companion->dev);
break;
}
}
}
}
static void set_hs_companion(struct pci_dev *pdev, struct usb_hcd *hcd)
{
mutex_lock(&companions_mutex);
dev_set_drvdata(&pdev->dev, hcd);
companion_common(pdev, hcd, SET_HS_COMPANION);
mutex_unlock(&companions_mutex);
}
static void clear_hs_companion(struct pci_dev *pdev, struct usb_hcd *hcd)
{
mutex_lock(&companions_mutex);
dev_set_drvdata(&pdev->dev, NULL);
/* If pdev is OHCI or UHCI, just clear its hs_companion pointer */
if (pdev->class == CL_OHCI || pdev->class == CL_UHCI)
hcd->self.hs_companion = NULL;
/* Otherwise search for companion buses and clear their pointers */
else
companion_common(pdev, hcd, CLEAR_HS_COMPANION);
mutex_unlock(&companions_mutex);
}
static void wait_for_companions(struct pci_dev *pdev, struct usb_hcd *hcd)
{
/* Only EHCI controllers need to wait.
* No locking is needed because a controller cannot be resumed
* while one of its companions is getting unbound.
*/
if (pdev->class == CL_EHCI)
companion_common(pdev, hcd, WAIT_FOR_COMPANIONS);
}
#else /* !CONFIG_PM_SLEEP */
static inline void set_hs_companion(struct pci_dev *d, struct usb_hcd *h) {}
static inline void clear_hs_companion(struct pci_dev *d, struct usb_hcd *h) {}
static inline void wait_for_companions(struct pci_dev *d, struct usb_hcd *h) {}
#endif /* !CONFIG_PM_SLEEP */
/*-------------------------------------------------------------------------*/
/* configure so an HC device and id are always provided */
/* always called with process context; sleeping is OK */
/**
* usb_hcd_pci_probe - initialize PCI-based HCDs
* @dev: USB Host Controller being probed
* @id: pci hotplug id connecting controller to HCD framework
* Context: !in_interrupt()
*
* Allocates basic PCI resources for this USB host controller, and
* then invokes the start() method for the HCD associated with it
* through the hotplug entry's driver_data.
*
* Store this function in the HCD's struct pci_driver as probe().
*/
int usb_hcd_pci_probe(struct pci_dev *dev, const struct pci_device_id *id)
{
struct hc_driver *driver;
struct usb_hcd *hcd;
int retval;
if (usb_disabled())
return -ENODEV;
if (!id)
return -EINVAL;
driver = (struct hc_driver *)id->driver_data;
if (!driver)
return -EINVAL;
if (pci_enable_device(dev) < 0)
return -ENODEV;
dev->current_state = PCI_D0;
if (!dev->irq) {
dev_err(&dev->dev,
"Found HC with no IRQ. Check BIOS/PCI %s setup!\n",
pci_name(dev));
retval = -ENODEV;
goto disable_pci;
}
hcd = usb_create_hcd(driver, &dev->dev, pci_name(dev));
if (!hcd) {
retval = -ENOMEM;
goto disable_pci;
}
if (driver->flags & HCD_MEMORY) {
/* EHCI, OHCI */
hcd->rsrc_start = pci_resource_start(dev, 0);
hcd->rsrc_len = pci_resource_len(dev, 0);
if (!request_mem_region(hcd->rsrc_start, hcd->rsrc_len,
driver->description)) {
dev_dbg(&dev->dev, "controller already in use\n");
retval = -EBUSY;
goto clear_companion;
}
hcd->regs = ioremap_nocache(hcd->rsrc_start, hcd->rsrc_len);
if (hcd->regs == NULL) {
dev_dbg(&dev->dev, "error mapping memory\n");
retval = -EFAULT;
goto release_mem_region;
}
} else {
/* UHCI */
int region;
for (region = 0; region < PCI_ROM_RESOURCE; region++) {
if (!(pci_resource_flags(dev, region) &
IORESOURCE_IO))
continue;
hcd->rsrc_start = pci_resource_start(dev, region);
hcd->rsrc_len = pci_resource_len(dev, region);
if (request_region(hcd->rsrc_start, hcd->rsrc_len,
driver->description))
break;
}
if (region == PCI_ROM_RESOURCE) {
dev_dbg(&dev->dev, "no i/o regions available\n");
retval = -EBUSY;
goto clear_companion;
}
}
pci_set_master(dev);
retval = usb_add_hcd(hcd, dev->irq, IRQF_DISABLED | IRQF_SHARED);
if (retval != 0)
goto unmap_registers;
2010-02-12 11:21:11 +00:00
set_hs_companion(dev, hcd);
if (pci_dev_run_wake(dev))
pm_runtime_put_noidle(&dev->dev);
return retval;
unmap_registers:
if (driver->flags & HCD_MEMORY) {
iounmap(hcd->regs);
release_mem_region:
release_mem_region(hcd->rsrc_start, hcd->rsrc_len);
} else
release_region(hcd->rsrc_start, hcd->rsrc_len);
clear_companion:
2010-02-12 11:21:11 +00:00
clear_hs_companion(dev, hcd);
usb_put_hcd(hcd);
disable_pci:
pci_disable_device(dev);
dev_err(&dev->dev, "init %s fail, %d\n", pci_name(dev), retval);
return retval;
}
EXPORT_SYMBOL_GPL(usb_hcd_pci_probe);
/* may be called without controller electrically present */
/* may be called with controller, bus, and devices active */
/**
* usb_hcd_pci_remove - shutdown processing for PCI-based HCDs
* @dev: USB Host Controller being removed
* Context: !in_interrupt()
*
* Reverses the effect of usb_hcd_pci_probe(), first invoking
* the HCD's stop() method. It is always called from a thread
* context, normally "rmmod", "apmd", or something similar.
*
* Store this function in the HCD's struct pci_driver as remove().
*/
void usb_hcd_pci_remove(struct pci_dev *dev)
{
struct usb_hcd *hcd;
hcd = pci_get_drvdata(dev);
if (!hcd)
return;
if (pci_dev_run_wake(dev))
pm_runtime_get_noresume(&dev->dev);
/* Fake an interrupt request in order to give the driver a chance
* to test whether the controller hardware has been removed (e.g.,
* cardbus physical eject).
*/
local_irq_disable();
usb_hcd_irq(0, hcd);
local_irq_enable();
usb_remove_hcd(hcd);
if (hcd->driver->flags & HCD_MEMORY) {
iounmap(hcd->regs);
release_mem_region(hcd->rsrc_start, hcd->rsrc_len);
} else {
release_region(hcd->rsrc_start, hcd->rsrc_len);
}
2010-02-12 11:21:11 +00:00
clear_hs_companion(dev, hcd);
usb_put_hcd(hcd);
pci_disable_device(dev);
}
EXPORT_SYMBOL_GPL(usb_hcd_pci_remove);
/**
* usb_hcd_pci_shutdown - shutdown host controller
* @dev: USB Host Controller being shutdown
*/
void usb_hcd_pci_shutdown(struct pci_dev *dev)
{
struct usb_hcd *hcd;
hcd = pci_get_drvdata(dev);
if (!hcd)
return;
if (test_bit(HCD_FLAG_HW_ACCESSIBLE, &hcd->flags) &&
OHCI: work around for nVidia shutdown problem This patch (as1417) fixes a problem affecting some (or all) nVidia chipsets. When the computer is shut down, the OHCI controllers continue to power the USB buses and evidently they drive a Reset signal out all their ports. This prevents attached devices from going to low power. Mouse LEDs stay on, for example, which is disconcerting for users and a drain on laptop batteries. The fix involves leaving each OHCI controller in the OPERATIONAL state during system shutdown rather than putting it in the RESET state. Although this nominally means the controller is running, in fact it's not doing very much since all the schedules are all disabled. However there is ongoing DMA to the Host Controller Communications Area, so the patch also disables the bus-master capability of all PCI USB controllers after the shutdown routine runs. The fix is applied only to nVidia-based PCI OHCI controllers, so it shouldn't cause problems on systems using other hardware. As an added safety measure, in case the kernel encounters one of these running controllers during boot, the patch changes quirk_usb_handoff_ohci() (which runs early on during PCI discovery) to reset the controller before anything bad can happen. Reported-by: Pali Rohár <pali.rohar@gmail.com> Signed-off-by: Alan Stern <stern@rowland.harvard.edu> CC: David Brownell <david-b@pacbell.net> Tested-by: Pali Rohár <pali.rohar@gmail.com> CC: stable <stable@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2010-09-10 20:37:05 +00:00
hcd->driver->shutdown) {
hcd->driver->shutdown(hcd);
OHCI: work around for nVidia shutdown problem This patch (as1417) fixes a problem affecting some (or all) nVidia chipsets. When the computer is shut down, the OHCI controllers continue to power the USB buses and evidently they drive a Reset signal out all their ports. This prevents attached devices from going to low power. Mouse LEDs stay on, for example, which is disconcerting for users and a drain on laptop batteries. The fix involves leaving each OHCI controller in the OPERATIONAL state during system shutdown rather than putting it in the RESET state. Although this nominally means the controller is running, in fact it's not doing very much since all the schedules are all disabled. However there is ongoing DMA to the Host Controller Communications Area, so the patch also disables the bus-master capability of all PCI USB controllers after the shutdown routine runs. The fix is applied only to nVidia-based PCI OHCI controllers, so it shouldn't cause problems on systems using other hardware. As an added safety measure, in case the kernel encounters one of these running controllers during boot, the patch changes quirk_usb_handoff_ohci() (which runs early on during PCI discovery) to reset the controller before anything bad can happen. Reported-by: Pali Rohár <pali.rohar@gmail.com> Signed-off-by: Alan Stern <stern@rowland.harvard.edu> CC: David Brownell <david-b@pacbell.net> Tested-by: Pali Rohár <pali.rohar@gmail.com> CC: stable <stable@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2010-09-10 20:37:05 +00:00
pci_disable_device(dev);
}
}
EXPORT_SYMBOL_GPL(usb_hcd_pci_shutdown);
#ifdef CONFIG_PM_OPS
#ifdef CONFIG_PPC_PMAC
static void powermac_set_asic(struct pci_dev *pci_dev, int enable)
{
/* Enanble or disable ASIC clocks for USB */
if (machine_is(powermac)) {
struct device_node *of_node;
of_node = pci_device_to_OF_node(pci_dev);
if (of_node)
pmac_call_feature(PMAC_FTR_USB_ENABLE,
of_node, 0, enable);
}
}
#else
static inline void powermac_set_asic(struct pci_dev *pci_dev, int enable)
{}
#endif /* CONFIG_PPC_PMAC */
static int check_root_hub_suspended(struct device *dev)
{
struct pci_dev *pci_dev = to_pci_dev(dev);
struct usb_hcd *hcd = pci_get_drvdata(pci_dev);
USB: move usbcore away from hcd->state The hcd->state variable is a disaster. It's not clearly owned by either usbcore or the host controller drivers, and they both change it from time to time, potentially stepping on each other's toes. It's not protected by any locks. And there's no mechanism to prevent it from going through an invalid transition. This patch (as1451) takes a first step toward fixing these problems. As it turns out, usbcore uses hcd->state for essentially only two things: checking whether the controller's root hub is running and checking whether the controller has died. Therefore the patch adds two new atomic bitflags to the hcd structure, to store these pieces of information. The new flags are used only by usbcore, and a private spinlock prevents invalid combinations (a dead controller's root hub cannot be running). The patch does not change the places where usbcore sets hcd->state, since HCDs may depend on them. Furthermore, there is one place in usb_hcd_irq() where usbcore still must use hcd->state: An HCD's interrupt handler can implicitly indicate that the controller died by setting hcd->state to HC_STATE_HALT. Nevertheless, the new code is a big improvement over the current code. The patch makes one other change. The hcd_bus_suspend() and hcd_bus_resume() routines now check first whether the host controller has died; if it has then they return immediately without calling the HCD's bus_suspend or bus_resume methods. This fixes the major problem reported in Bugzilla #29902: The system fails to suspend after a host controller dies during system resume. Signed-off-by: Alan Stern <stern@rowland.harvard.edu> Tested-by: Alex Terekhov <a.terekhov@gmail.com> CC: <stable@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2011-03-07 16:11:52 +00:00
if (HCD_RH_RUNNING(hcd)) {
dev_warn(dev, "Root hub is not suspended\n");
return -EBUSY;
}
return 0;
}
static int suspend_common(struct device *dev, bool do_wakeup)
{
struct pci_dev *pci_dev = to_pci_dev(dev);
struct usb_hcd *hcd = pci_get_drvdata(pci_dev);
int retval;
/* Root hub suspend should have stopped all downstream traffic,
* and all bus master traffic. And done so for both the interface
* and the stub usb_device (which we check here). But maybe it
* didn't; writing sysfs power/state files ignores such rules...
*/
retval = check_root_hub_suspended(dev);
if (retval)
return retval;
USB: move usbcore away from hcd->state The hcd->state variable is a disaster. It's not clearly owned by either usbcore or the host controller drivers, and they both change it from time to time, potentially stepping on each other's toes. It's not protected by any locks. And there's no mechanism to prevent it from going through an invalid transition. This patch (as1451) takes a first step toward fixing these problems. As it turns out, usbcore uses hcd->state for essentially only two things: checking whether the controller's root hub is running and checking whether the controller has died. Therefore the patch adds two new atomic bitflags to the hcd structure, to store these pieces of information. The new flags are used only by usbcore, and a private spinlock prevents invalid combinations (a dead controller's root hub cannot be running). The patch does not change the places where usbcore sets hcd->state, since HCDs may depend on them. Furthermore, there is one place in usb_hcd_irq() where usbcore still must use hcd->state: An HCD's interrupt handler can implicitly indicate that the controller died by setting hcd->state to HC_STATE_HALT. Nevertheless, the new code is a big improvement over the current code. The patch makes one other change. The hcd_bus_suspend() and hcd_bus_resume() routines now check first whether the host controller has died; if it has then they return immediately without calling the HCD's bus_suspend or bus_resume methods. This fixes the major problem reported in Bugzilla #29902: The system fails to suspend after a host controller dies during system resume. Signed-off-by: Alan Stern <stern@rowland.harvard.edu> Tested-by: Alex Terekhov <a.terekhov@gmail.com> CC: <stable@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2011-03-07 16:11:52 +00:00
if (hcd->driver->pci_suspend && !HCD_DEAD(hcd)) {
/* Optimization: Don't suspend if a root-hub wakeup is
* pending and it would cause the HCD to wake up anyway.
*/
if (do_wakeup && HCD_WAKEUP_PENDING(hcd))
return -EBUSY;
retval = hcd->driver->pci_suspend(hcd, do_wakeup);
suspend_report_result(hcd->driver->pci_suspend, retval);
/* Check again in case wakeup raced with pci_suspend */
if (retval == 0 && do_wakeup && HCD_WAKEUP_PENDING(hcd)) {
if (hcd->driver->pci_resume)
hcd->driver->pci_resume(hcd, false);
retval = -EBUSY;
}
if (retval)
return retval;
}
/* If MSI-X is enabled, the driver will have synchronized all vectors
* in pci_suspend(). If MSI or legacy PCI is enabled, that will be
* synchronized here.
*/
if (!hcd->msix_enabled)
synchronize_irq(pci_dev->irq);
/* Downstream ports from this root hub should already be quiesced, so
* there will be no DMA activity. Now we can shut down the upstream
* link (except maybe for PME# resume signaling). We'll enter a
* low power state during suspend_noirq, if the hardware allows.
*/
pci_disable_device(pci_dev);
return retval;
}
static int resume_common(struct device *dev, int event)
{
struct pci_dev *pci_dev = to_pci_dev(dev);
struct usb_hcd *hcd = pci_get_drvdata(pci_dev);
int retval;
USB: move usbcore away from hcd->state The hcd->state variable is a disaster. It's not clearly owned by either usbcore or the host controller drivers, and they both change it from time to time, potentially stepping on each other's toes. It's not protected by any locks. And there's no mechanism to prevent it from going through an invalid transition. This patch (as1451) takes a first step toward fixing these problems. As it turns out, usbcore uses hcd->state for essentially only two things: checking whether the controller's root hub is running and checking whether the controller has died. Therefore the patch adds two new atomic bitflags to the hcd structure, to store these pieces of information. The new flags are used only by usbcore, and a private spinlock prevents invalid combinations (a dead controller's root hub cannot be running). The patch does not change the places where usbcore sets hcd->state, since HCDs may depend on them. Furthermore, there is one place in usb_hcd_irq() where usbcore still must use hcd->state: An HCD's interrupt handler can implicitly indicate that the controller died by setting hcd->state to HC_STATE_HALT. Nevertheless, the new code is a big improvement over the current code. The patch makes one other change. The hcd_bus_suspend() and hcd_bus_resume() routines now check first whether the host controller has died; if it has then they return immediately without calling the HCD's bus_suspend or bus_resume methods. This fixes the major problem reported in Bugzilla #29902: The system fails to suspend after a host controller dies during system resume. Signed-off-by: Alan Stern <stern@rowland.harvard.edu> Tested-by: Alex Terekhov <a.terekhov@gmail.com> CC: <stable@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2011-03-07 16:11:52 +00:00
if (HCD_RH_RUNNING(hcd)) {
dev_dbg(dev, "can't resume, not suspended!\n");
return 0;
}
retval = pci_enable_device(pci_dev);
if (retval < 0) {
dev_err(dev, "can't re-enable after resume, %d!\n", retval);
return retval;
}
pci_set_master(pci_dev);
clear_bit(HCD_FLAG_SAW_IRQ, &hcd->flags);
USB: move usbcore away from hcd->state The hcd->state variable is a disaster. It's not clearly owned by either usbcore or the host controller drivers, and they both change it from time to time, potentially stepping on each other's toes. It's not protected by any locks. And there's no mechanism to prevent it from going through an invalid transition. This patch (as1451) takes a first step toward fixing these problems. As it turns out, usbcore uses hcd->state for essentially only two things: checking whether the controller's root hub is running and checking whether the controller has died. Therefore the patch adds two new atomic bitflags to the hcd structure, to store these pieces of information. The new flags are used only by usbcore, and a private spinlock prevents invalid combinations (a dead controller's root hub cannot be running). The patch does not change the places where usbcore sets hcd->state, since HCDs may depend on them. Furthermore, there is one place in usb_hcd_irq() where usbcore still must use hcd->state: An HCD's interrupt handler can implicitly indicate that the controller died by setting hcd->state to HC_STATE_HALT. Nevertheless, the new code is a big improvement over the current code. The patch makes one other change. The hcd_bus_suspend() and hcd_bus_resume() routines now check first whether the host controller has died; if it has then they return immediately without calling the HCD's bus_suspend or bus_resume methods. This fixes the major problem reported in Bugzilla #29902: The system fails to suspend after a host controller dies during system resume. Signed-off-by: Alan Stern <stern@rowland.harvard.edu> Tested-by: Alex Terekhov <a.terekhov@gmail.com> CC: <stable@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2011-03-07 16:11:52 +00:00
if (hcd->driver->pci_resume && !HCD_DEAD(hcd)) {
if (event != PM_EVENT_AUTO_RESUME)
wait_for_companions(pci_dev, hcd);
retval = hcd->driver->pci_resume(hcd,
event == PM_EVENT_RESTORE);
if (retval) {
dev_err(dev, "PCI post-resume error %d!\n", retval);
usb_hc_died(hcd);
}
}
return retval;
}
#ifdef CONFIG_PM_SLEEP
static int hcd_pci_suspend(struct device *dev)
{
return suspend_common(dev, device_may_wakeup(dev));
}
static int hcd_pci_suspend_noirq(struct device *dev)
{
struct pci_dev *pci_dev = to_pci_dev(dev);
struct usb_hcd *hcd = pci_get_drvdata(pci_dev);
int retval;
retval = check_root_hub_suspended(dev);
if (retval)
return retval;
pci_save_state(pci_dev);
USB: move usbcore away from hcd->state The hcd->state variable is a disaster. It's not clearly owned by either usbcore or the host controller drivers, and they both change it from time to time, potentially stepping on each other's toes. It's not protected by any locks. And there's no mechanism to prevent it from going through an invalid transition. This patch (as1451) takes a first step toward fixing these problems. As it turns out, usbcore uses hcd->state for essentially only two things: checking whether the controller's root hub is running and checking whether the controller has died. Therefore the patch adds two new atomic bitflags to the hcd structure, to store these pieces of information. The new flags are used only by usbcore, and a private spinlock prevents invalid combinations (a dead controller's root hub cannot be running). The patch does not change the places where usbcore sets hcd->state, since HCDs may depend on them. Furthermore, there is one place in usb_hcd_irq() where usbcore still must use hcd->state: An HCD's interrupt handler can implicitly indicate that the controller died by setting hcd->state to HC_STATE_HALT. Nevertheless, the new code is a big improvement over the current code. The patch makes one other change. The hcd_bus_suspend() and hcd_bus_resume() routines now check first whether the host controller has died; if it has then they return immediately without calling the HCD's bus_suspend or bus_resume methods. This fixes the major problem reported in Bugzilla #29902: The system fails to suspend after a host controller dies during system resume. Signed-off-by: Alan Stern <stern@rowland.harvard.edu> Tested-by: Alex Terekhov <a.terekhov@gmail.com> CC: <stable@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2011-03-07 16:11:52 +00:00
/* If the root hub is dead rather than suspended,
* disallow remote wakeup.
*/
USB: move usbcore away from hcd->state The hcd->state variable is a disaster. It's not clearly owned by either usbcore or the host controller drivers, and they both change it from time to time, potentially stepping on each other's toes. It's not protected by any locks. And there's no mechanism to prevent it from going through an invalid transition. This patch (as1451) takes a first step toward fixing these problems. As it turns out, usbcore uses hcd->state for essentially only two things: checking whether the controller's root hub is running and checking whether the controller has died. Therefore the patch adds two new atomic bitflags to the hcd structure, to store these pieces of information. The new flags are used only by usbcore, and a private spinlock prevents invalid combinations (a dead controller's root hub cannot be running). The patch does not change the places where usbcore sets hcd->state, since HCDs may depend on them. Furthermore, there is one place in usb_hcd_irq() where usbcore still must use hcd->state: An HCD's interrupt handler can implicitly indicate that the controller died by setting hcd->state to HC_STATE_HALT. Nevertheless, the new code is a big improvement over the current code. The patch makes one other change. The hcd_bus_suspend() and hcd_bus_resume() routines now check first whether the host controller has died; if it has then they return immediately without calling the HCD's bus_suspend or bus_resume methods. This fixes the major problem reported in Bugzilla #29902: The system fails to suspend after a host controller dies during system resume. Signed-off-by: Alan Stern <stern@rowland.harvard.edu> Tested-by: Alex Terekhov <a.terekhov@gmail.com> CC: <stable@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2011-03-07 16:11:52 +00:00
if (HCD_DEAD(hcd))
device_set_wakeup_enable(dev, 0);
dev_dbg(dev, "wakeup: %d\n", device_may_wakeup(dev));
/* Possibly enable remote wakeup,
* choose the appropriate low-power state, and go to that state.
*/
retval = pci_prepare_to_sleep(pci_dev);
if (retval == -EIO) { /* Low-power not supported */
dev_dbg(dev, "--> PCI D0 legacy\n");
retval = 0;
} else if (retval == 0) {
dev_dbg(dev, "--> PCI %s\n",
pci_power_name(pci_dev->current_state));
} else {
suspend_report_result(pci_prepare_to_sleep, retval);
return retval;
}
powermac_set_asic(pci_dev, 0);
return retval;
}
static int hcd_pci_resume_noirq(struct device *dev)
{
struct pci_dev *pci_dev = to_pci_dev(dev);
powermac_set_asic(pci_dev, 1);
/* Go back to D0 and disable remote wakeup */
pci_back_from_sleep(pci_dev);
return 0;
}
static int hcd_pci_resume(struct device *dev)
{
return resume_common(dev, PM_EVENT_RESUME);
}
static int hcd_pci_restore(struct device *dev)
{
return resume_common(dev, PM_EVENT_RESTORE);
}
#else
#define hcd_pci_suspend NULL
#define hcd_pci_suspend_noirq NULL
#define hcd_pci_resume_noirq NULL
#define hcd_pci_resume NULL
#define hcd_pci_restore NULL
#endif /* CONFIG_PM_SLEEP */
#ifdef CONFIG_PM_RUNTIME
static int hcd_pci_runtime_suspend(struct device *dev)
{
int retval;
retval = suspend_common(dev, true);
if (retval == 0)
powermac_set_asic(to_pci_dev(dev), 0);
dev_dbg(dev, "hcd_pci_runtime_suspend: %d\n", retval);
return retval;
}
static int hcd_pci_runtime_resume(struct device *dev)
{
int retval;
powermac_set_asic(to_pci_dev(dev), 1);
retval = resume_common(dev, PM_EVENT_AUTO_RESUME);
dev_dbg(dev, "hcd_pci_runtime_resume: %d\n", retval);
return retval;
}
#else
#define hcd_pci_runtime_suspend NULL
#define hcd_pci_runtime_resume NULL
#endif /* CONFIG_PM_RUNTIME */
const struct dev_pm_ops usb_hcd_pci_pm_ops = {
.suspend = hcd_pci_suspend,
.suspend_noirq = hcd_pci_suspend_noirq,
.resume_noirq = hcd_pci_resume_noirq,
.resume = hcd_pci_resume,
.freeze = check_root_hub_suspended,
.freeze_noirq = check_root_hub_suspended,
.thaw_noirq = NULL,
.thaw = NULL,
.poweroff = hcd_pci_suspend,
.poweroff_noirq = hcd_pci_suspend_noirq,
.restore_noirq = hcd_pci_resume_noirq,
.restore = hcd_pci_restore,
.runtime_suspend = hcd_pci_runtime_suspend,
.runtime_resume = hcd_pci_runtime_resume,
};
EXPORT_SYMBOL_GPL(usb_hcd_pci_pm_ops);
#endif /* CONFIG_PM_OPS */