With this and some other patches (OHCI, EHCI, and hub for starters), I'm
seeing swsusp partially behaving with usb loaded.
This one makes the usbcore pci suspend/resume logic treat "legacy"
devices the same as "pci pm" devices ... and vice versa. It's that
second part which will be interesting to some folk: legacy devices
never fail a suspend request, so now ones with pci-pm won't either.
As a side effect, that means it works around osdl bugid 2886 (where
the pm core code is using PCI-incompatible power states).
- Dave
Handle "legacy" (non-PM) devices better
- basically just suspend hub and act as if the hardware were pm-aware
- update dev->current_state, per API spec
- accept all suspend states (no power reductions though)
Implement the PCI API better
- use D3hot suspend if D1/D2 was requested but the hardware can't do that,
to be just as forgiving as "legacy" devices (also doubles as a USB-specific
workaround for OSDL bugid 2886).
- handle "suspend deeper" (D1->D2, D2->D3hot, etc)
Minor fixes:
- when debugging, dump the PCI PM states by name ("D3hot" etc)
- there are no states beyond D3cold
Signed-off-by: David Brownell <[EMAIL PROTECTED]>
--- xu26/drivers/usb/core/hcd-pci.c 2004-09-09 18:46:18.000000000 -0700
+++ gadget-2.6/drivers/usb/core/hcd-pci.c 2004-09-10 18:02:18.000000000 -0700
@@ -266,6 +266,18 @@
#ifdef CONFIG_PM
+static char *pci_state(u32 state)
+{
+ switch (state) {
+ case 0: return "D0";
+ case 1: return "D1";
+ case 2: return "D2";
+ case 3: return "D3hot";
+ case 4: return "D3cold";
+ }
+ return NULL;
+}
+
/**
* usb_hcd_pci_suspend - power management suspend of a PCI-based HCD
* @dev: USB Host Controller being suspended
@@ -286,16 +298,34 @@
* PM-sensitive HCDs may already have done this.
*/
has_pci_pm = pci_find_capability(dev, PCI_CAP_ID_PM);
- if (has_pci_pm)
- dev_dbg(hcd->self.controller, "suspend D%d --> D%d\n",
- dev->current_state, state);
+ if (state > 4)
+ state = 4;
switch (hcd->state) {
case USB_STATE_HALT:
dev_dbg (hcd->self.controller, "halted; hcd not suspended\n");
break;
case HCD_STATE_SUSPENDED:
- dev_dbg (hcd->self.controller, "hcd already suspended\n");
+ dev_dbg (hcd->self.controller, "PCI %s --> %s\n",
+ pci_state(dev->current_state),
+ pci_state(state));
+ if (state > 3)
+ state = 3;
+
+ if (state == dev->current_state)
+ break;
+ else if (state < dev->current_state)
+ retval = -EIO;
+ else if (has_pci_pm)
+ retval = pci_set_power_state (dev, state);
+ else
+ dev->current_state = state;
+
+ if (retval == 0)
+ dev->dev.power.power_state = state;
+ else
+ dev_dbg (hcd->self.controller,
+ "re-suspend fail, %d\n", retval);
break;
default:
retval = hcd->driver->suspend (hcd, state);
@@ -306,22 +336,48 @@
else {
hcd->state = HCD_STATE_SUSPENDED;
pci_save_state (dev, hcd->pci_state);
-#ifdef CONFIG_USB_SUSPEND
- pci_enable_wake (dev, state, hcd->remote_wakeup);
- pci_enable_wake (dev, 4, hcd->remote_wakeup);
-#endif
+
/* no DMA or IRQs except in D0 */
pci_disable_device (dev);
free_irq (hcd->irq, hcd);
- if (has_pci_pm)
+ if (has_pci_pm) {
retval = pci_set_power_state (dev, state);
- dev->dev.power.power_state = state;
+
+ /* POLICY: mask D1/D2/D3hot differences;
+ * we know D3hot will always work.
+ */
+ if (retval < 0 && state < 3) {
+ retval = pci_set_power_state (dev, 3);
+ if (retval == 0)
+ state = 3;
+ }
+ if (retval == 0) {
+ dev->dev.power.power_state = state;
+#ifdef CONFIG_USB_SUSPEND
+ pci_enable_wake (dev, state,
+ hcd->remote_wakeup);
+ pci_enable_wake (dev, 4,
+ hcd->remote_wakeup);
+#endif
+ }
+ } else {
+ if (state > 3)
+ state = 3;
+ dev->current_state = state;
+ dev->dev.power.power_state = state;
+ }
if (retval < 0) {
dev_dbg (&dev->dev,
- "PCI suspend fail, %d\n",
+ "PCI %s suspend fail, %d\n",
+ pci_state(state),
retval);
(void) usb_hcd_pci_resume (dev);
+ } else {
+ dev_dbg(hcd->self.controller,
+ "suspended to PCI %s%s\n",
+ pci_state(state),
+ has_pci_pm ? " (PM)" : "");
}
}
}
@@ -343,9 +399,10 @@
hcd = pci_get_drvdata(dev);
has_pci_pm = pci_find_capability(dev, PCI_CAP_ID_PM);
- if (has_pci_pm)
- dev_dbg(hcd->self.controller, "resume from state D%d\n",
- dev->current_state);
+
+ /* D3cold resume isn't usually reported this way... */
+ dev_dbg(hcd->self.controller, "resume from PCI %s\n",
+ pci_state(dev->current_state));
if (hcd->state != HCD_STATE_SUSPENDED) {
dev_dbg (hcd->self.controller,
@@ -356,6 +413,8 @@
if (has_pci_pm)
pci_set_power_state (dev, 0);
+ else
+ dev->current_state = 0;
dev->dev.power.power_state = 0;
retval = request_irq (dev->irq, usb_hcd_irq, SA_SHIRQ,
hcd->description, hcd);
