[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(-)
diff --git a/drivers/usb/core/hcd-pci.c b/drivers/usb/core/hcd-pci.c
index 6385d1a..84d9e69 100644
--- a/drivers/usb/core/hcd-pci.c
+++ b/drivers/usb/core/hcd-pci.c
@@ -30,6 +30,8 @@
#include <asm/io.h>
#include <asm/irq.h>
#include <linux/usb.h>
+
+#include "usb.h"
#include "hcd.h"
@@ -197,6 +199,26 @@
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
@@ -215,31 +237,13 @@
*/
has_pci_pm = pci_find_capability(dev, PCI_CAP_ID_PM);
- switch (hcd->state) {
-
- /* entry if root hub wasn't yet suspended ... from sysfs,
- * without autosuspend, or if USB_SUSPEND isn't configured.
+ /* 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.
*/
- case HC_STATE_RUNNING:
- hcd->state = HC_STATE_QUIESCING;
- retval = hcd->driver->suspend (hcd, message);
- if (retval) {
- dev_dbg (hcd->self.controller,
- "suspend fail, retval %d\n",
- retval);
- break;
- }
- hcd->state = HC_STATE_SUSPENDED;
- /* FALLTHROUGH */
+ if (hcd->state == HC_STATE_SUSPENDED) {
- /* entry with CONFIG_USB_SUSPEND, or hcds that autosuspend: the
- * controller and/or root hub will already have been suspended,
- * but it won't be ready for a PCI resume call.
- *
- * FIXME only CONFIG_USB_SUSPEND guarantees hub_suspend() will
- * have been called, otherwise root hub timers still run ...
- */
- case HC_STATE_SUSPENDED:
/* no DMA or IRQs except when HC is active */
if (dev->current_state == PCI_D0) {
pci_save_state (dev);
@@ -248,7 +252,7 @@
if (!has_pci_pm) {
dev_dbg (hcd->self.controller, "--> PCI D0/legacy\n");
- break;
+ goto done;
}
/* NOTE: dev->current_state becomes nonzero only here, and
@@ -259,28 +263,29 @@
retval = pci_set_power_state (dev, PCI_D3hot);
if (retval == 0) {
dev_dbg (hcd->self.controller, "--> PCI D3\n");
- retval = pci_enable_wake (dev, PCI_D3hot, hcd->remote_wakeup);
- if (retval)
- break;
- retval = pci_enable_wake (dev, PCI_D3cold, hcd->remote_wakeup);
- } else if (retval < 0) {
+
+ /* 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);
- break;
}
- break;
- default:
+
+ } else {
dev_dbg (hcd->self.controller, "hcd state %d; not suspended\n",
hcd->state);
WARN_ON(1);
retval = -EINVAL;
- break;
}
- /* update power_state **ONLY** to make sysfs happier */
+done:
if (retval == 0)
- dev->dev.power.power_state = message;
+ dev->dev.power.power_state = PMSG_SUSPEND;
return retval;
}
EXPORT_SYMBOL (usb_hcd_pci_suspend);
@@ -336,20 +341,9 @@
dev->current_state);
}
#endif
- retval = pci_enable_wake (dev, dev->current_state, 0);
- if (retval) {
- dev_err(hcd->self.controller,
- "can't enable_wake to %d, %d!\n",
- dev->current_state, retval);
- return retval;
- }
- retval = pci_enable_wake (dev, PCI_D3cold, 0);
- if (retval) {
- dev_err(hcd->self.controller,
- "can't enable_wake to %d, %d!\n",
- PCI_D3cold, retval);
- return retval;
- }
+ /* 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");
@@ -371,17 +365,17 @@
dev->dev.power.power_state = PMSG_ON;
- hcd->state = HC_STATE_RESUMING;
hcd->saw_irq = 0;
- retval = hcd->driver->resume (hcd);
- if (!HC_IS_RUNNING (hcd->state)) {
- dev_dbg (hcd->self.controller,
- "resume fail, retval %d\n", retval);
- usb_hc_died (hcd);
+ 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);
+ }
}
- retval = pci_enable_device(dev);
return retval;
}
EXPORT_SYMBOL (usb_hcd_pci_resume);
diff --git a/drivers/usb/core/hcd.h b/drivers/usb/core/hcd.h
index eb21f13..74757fc 100644
--- a/drivers/usb/core/hcd.h
+++ b/drivers/usb/core/hcd.h
@@ -182,12 +182,12 @@
int (*start) (struct usb_hcd *hcd);
/* NOTE: these suspend/resume calls relate to the HC as
- * a whole, not just the root hub; they're for bus glue.
+ * a whole, not just the root hub; they're for PCI bus glue.
*/
- /* called after all devices were suspended */
+ /* called after suspending the hub, before entering D3 etc */
int (*suspend) (struct usb_hcd *hcd, pm_message_t message);
- /* called before any devices get resumed */
+ /* called after entering D0 (etc), before resuming the hub */
int (*resume) (struct usb_hcd *hcd);
/* cleanly make HCD stop writing memory and doing I/O */