linux/drivers/usb/core/hcd-pci.c
Alan Stern 6ec4beb5c7 USB: new flag for resume-from-hibernation
This patch (as1237) changes the way the PCI host controller drivers
avoid retaining bogus hardware states during resume-from-hibernation.
Previously we had reset the hardware as part of preparing to reinstate
the memory image.  But we can do better now with the new PM framework,
since we know exactly which resume operations are from hibernation.

The pci_resume method is changed to accept a flag indicating whether
the system is resuming from hibernation.  When this flag is set, the
drivers will reset the hardware to get rid of any existing state.

Similarly, the pci_suspend method is changed to remove the
pm_message_t argument.  It's no longer needed, since no special action
has to be taken when preparing to reinstate the memory image.

Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Acked-by: Rafael J. Wysocki <rjw@sisk.pl>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2009-06-15 21:44:44 -07:00

382 lines
9.5 KiB
C

/*
* (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 <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"
#include "hcd.h"
/* PCI-based HCs are common, but plenty of non-PCI HCs are used too */
/*-------------------------------------------------------------------------*/
/* 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 err1;
}
hcd = usb_create_hcd(driver, &dev->dev, pci_name(dev));
if (!hcd) {
retval = -ENOMEM;
goto err1;
}
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 err2;
}
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 err3;
}
} 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 err1;
}
}
pci_set_master(dev);
retval = usb_add_hcd(hcd, dev->irq, IRQF_DISABLED | IRQF_SHARED);
if (retval != 0)
goto err4;
return retval;
err4:
if (driver->flags & HCD_MEMORY) {
iounmap(hcd->regs);
err3:
release_mem_region(hcd->rsrc_start, hcd->rsrc_len);
} else
release_region(hcd->rsrc_start, hcd->rsrc_len);
err2:
usb_put_hcd(hcd);
err1:
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;
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);
}
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 (hcd->driver->shutdown)
hcd->driver->shutdown(hcd);
}
EXPORT_SYMBOL_GPL(usb_hcd_pci_shutdown);
#ifdef CONFIG_PM_SLEEP
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);
if (!(hcd->state == HC_STATE_SUSPENDED ||
hcd->state == HC_STATE_HALT)) {
dev_warn(dev, "Root hub is not suspended\n");
return -EBUSY;
}
return 0;
}
static int hcd_pci_suspend(struct device *dev)
{
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;
/* We might already be suspended (runtime PM -- not yet written) */
if (pci_dev->current_state != PCI_D0)
return retval;
if (hcd->driver->pci_suspend) {
retval = hcd->driver->pci_suspend(hcd);
suspend_report_result(hcd->driver->pci_suspend, retval);
if (retval)
return retval;
}
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 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);
/* If the root hub is HALTed rather than SUSPENDed,
* disallow remote wakeup.
*/
if (hcd->state == HC_STATE_HALT)
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;
}
#ifdef CONFIG_PPC_PMAC
/* 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, 0);
}
#endif
return retval;
}
static int hcd_pci_resume_noirq(struct device *dev)
{
struct pci_dev *pci_dev = to_pci_dev(dev);
#ifdef CONFIG_PPC_PMAC
/* Reenable 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, 1);
}
#endif
/* Go back to D0 and disable remote wakeup */
pci_back_from_sleep(pci_dev);
return 0;
}
static int resume_common(struct device *dev, bool hibernated)
{
struct pci_dev *pci_dev = to_pci_dev(dev);
struct usb_hcd *hcd = pci_get_drvdata(pci_dev);
int retval;
if (hcd->state != HC_STATE_SUSPENDED) {
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);
if (hcd->driver->pci_resume) {
retval = hcd->driver->pci_resume(hcd, hibernated);
if (retval) {
dev_err(dev, "PCI post-resume error %d!\n", retval);
usb_hc_died(hcd);
}
}
return retval;
}
static int hcd_pci_resume(struct device *dev)
{
return resume_common(dev, false);
}
static int hcd_pci_restore(struct device *dev)
{
return resume_common(dev, true);
}
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,
};
EXPORT_SYMBOL_GPL(usb_hcd_pci_pm_ops);
#endif /* CONFIG_PM_SLEEP */