linux/drivers/usb/core/hcd-pci.c
David Brownell 5f827ea3c3 [PATCH] usbcore PCI glue updates for PM
This updates the PCI glue to address the new and simplified usbcore suspend
semantics, where CONFIG_USB_SUSPEND becomes irrelevant to HCDs because
hcd->hub_suspend() will always be called.

  - Removes now-unneeded recursion support

  - Go back to ignoring faults reported by the wakeup calls; we expect them
    to fail sometimes, and that's just fine.

The PCI HCDs will need simple changes to catch up to this, like being able
to ignore the setting of CONFIG_USB_SUSPEND.

Signed-off-by: David Brownell <dbrownell@users.sourceforge.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

 drivers/usb/core/hcd-pci.c |  106 +++++++++++++++++++++------------------------
 drivers/usb/core/hcd.h     |    6 +-
 2 files changed, 53 insertions(+), 59 deletions(-)
2005-10-28 16:47:40 -07:00

386 lines
11 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/config.h>
#ifdef CONFIG_USB_DEBUG
#define DEBUG
#else
#undef DEBUG
#endif
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/pci.h>
#include <asm/io.h>
#include <asm/irq.h>
#include <linux/usb.h>
#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 || !(driver = (struct hc_driver *) id->driver_data))
return -EINVAL;
if (pci_enable_device (dev) < 0)
return -ENODEV;
dev->current_state = PCI_D0;
dev->dev.power.power_state = PMSG_ON;
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, SA_SHIRQ);
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 (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 (usb_hcd_pci_remove);
#ifdef CONFIG_PM
/**
* usb_hcd_pci_suspend - power management suspend of a PCI-based HCD
* @dev: USB Host Controller being suspended
* @message: semantics in flux
*
* Store this function in the HCD's struct pci_driver as suspend().
*/
int usb_hcd_pci_suspend (struct pci_dev *dev, pm_message_t message)
{
struct usb_hcd *hcd;
int retval = 0;
int has_pci_pm;
hcd = pci_get_drvdata(dev);
/* 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...
*
* We must ignore the FREEZE vs SUSPEND distinction here, because
* otherwise the swsusp will save (and restore) garbage state.
*/
if (hcd->self.root_hub->dev.power.power_state.event == PM_EVENT_ON)
return -EBUSY;
if (hcd->driver->suspend) {
retval = hcd->driver->suspend(hcd, message);
if (retval) {
dev_dbg (&dev->dev, "PCI pre-suspend fail, %d\n",
retval);
goto done;
}
}
/* FIXME until the generic PM interfaces change a lot more, this
* can't use PCI D1 and D2 states. For example, the confusion
* between messages and states will need to vanish, and messages
* will need to provide a target system state again.
*
* It'll be important to learn characteristics of the target state,
* especially on embedded hardware where the HCD will often be in
* charge of an external VBUS power supply and one or more clocks.
* Some target system states will leave them active; others won't.
* (With PCI, that's often handled by platform BIOS code.)
*/
/* even when the PCI layer rejects some of the PCI calls
* below, HCs can try global suspend and reduce DMA traffic.
* PM-sensitive HCDs may already have done this.
*/
has_pci_pm = pci_find_capability(dev, PCI_CAP_ID_PM);
/* 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) and enter some PCI
* low power state, if the hardware allows.
*/
if (hcd->state == HC_STATE_SUSPENDED) {
/* no DMA or IRQs except when HC is active */
if (dev->current_state == PCI_D0) {
pci_save_state (dev);
pci_disable_device (dev);
}
if (!has_pci_pm) {
dev_dbg (hcd->self.controller, "--> PCI D0/legacy\n");
goto done;
}
/* NOTE: dev->current_state becomes nonzero only here, and
* only for devices that support PCI PM. Also, exiting
* PCI_D3 (but not PCI_D1 or PCI_D2) is allowed to reset
* some device state (e.g. as part of clock reinit).
*/
retval = pci_set_power_state (dev, PCI_D3hot);
if (retval == 0) {
dev_dbg (hcd->self.controller, "--> PCI D3\n");
/* Ignore these return values. We rely on pci code to
* reject requests the hardware can't implement, rather
* than coding the same thing.
*/
(void) pci_enable_wake (dev, PCI_D3hot, hcd->remote_wakeup);
(void) pci_enable_wake (dev, PCI_D3cold, hcd->remote_wakeup);
} else {
dev_dbg (&dev->dev, "PCI D3 suspend fail, %d\n",
retval);
(void) usb_hcd_pci_resume (dev);
}
} else {
dev_dbg (hcd->self.controller, "hcd state %d; not suspended\n",
hcd->state);
WARN_ON(1);
retval = -EINVAL;
}
done:
if (retval == 0)
dev->dev.power.power_state = PMSG_SUSPEND;
return retval;
}
EXPORT_SYMBOL (usb_hcd_pci_suspend);
/**
* usb_hcd_pci_resume - power management resume of a PCI-based HCD
* @dev: USB Host Controller being resumed
*
* Store this function in the HCD's struct pci_driver as resume().
*/
int usb_hcd_pci_resume (struct pci_dev *dev)
{
struct usb_hcd *hcd;
int retval;
hcd = pci_get_drvdata(dev);
if (hcd->state != HC_STATE_SUSPENDED) {
dev_dbg (hcd->self.controller,
"can't resume, not suspended!\n");
return 0;
}
/* NOTE: chip docs cover clean "real suspend" cases (what Linux
* calls "standby", "suspend to RAM", and so on). There are also
* dirty cases when swsusp fakes a suspend in "shutdown" mode.
*/
if (dev->current_state != PCI_D0) {
#ifdef DEBUG
int pci_pm;
u16 pmcr;
pci_pm = pci_find_capability(dev, PCI_CAP_ID_PM);
pci_read_config_word(dev, pci_pm + PCI_PM_CTRL, &pmcr);
pmcr &= PCI_PM_CTRL_STATE_MASK;
if (pmcr) {
/* Clean case: power to USB and to HC registers was
* maintained; remote wakeup is easy.
*/
dev_dbg(hcd->self.controller, "resume from PCI D%d\n",
pmcr);
} else {
/* Clean: HC lost Vcc power, D0 uninitialized
* + Vaux may have preserved port and transceiver
* state ... for remote wakeup from D3cold
* + or not; HCD must reinit + re-enumerate
*
* Dirty: D0 semi-initialized cases with swsusp
* + after BIOS init
* + after Linux init (HCD statically linked)
*/
dev_dbg(hcd->self.controller,
"PCI D0, from previous PCI D%d\n",
dev->current_state);
}
#endif
/* yes, ignore these results too... */
(void) pci_enable_wake (dev, dev->current_state, 0);
(void) pci_enable_wake (dev, PCI_D3cold, 0);
} else {
/* Same basic cases: clean (powered/not), dirty */
dev_dbg(hcd->self.controller, "PCI legacy resume\n");
}
/* NOTE: the PCI API itself is asymmetric here. We don't need to
* pci_set_power_state(PCI_D0) since that's part of re-enabling;
* but that won't re-enable bus mastering. Yet pci_disable_device()
* explicitly disables bus mastering...
*/
retval = pci_enable_device (dev);
if (retval < 0) {
dev_err (hcd->self.controller,
"can't re-enable after resume, %d!\n", retval);
return retval;
}
pci_set_master (dev);
pci_restore_state (dev);
dev->dev.power.power_state = PMSG_ON;
hcd->saw_irq = 0;
if (hcd->driver->resume) {
retval = hcd->driver->resume(hcd);
if (retval) {
dev_err (hcd->self.controller,
"PCI post-resume error %d!\n", retval);
usb_hc_died (hcd);
}
}
return retval;
}
EXPORT_SYMBOL (usb_hcd_pci_resume);
#endif /* CONFIG_PM */