[PATCH] OHCI PM updates

This simplifies the OHCI root hub suspend logic:

 - Uses new usbcore root hub calls to make autosuspend work again:
	* Uses a newish usbcore root hub wakeup mechanism,
	  making requests to khubd not keventd.
	* Uses an even newer sibling suspend hook.

 - Expect someone always made usbcore call ohci_hub_suspend() before bus
   glue fires; and that ohci_hub_resume() is only called after that bus
   glue ran.  Previously, only CONFIG_USB_SUSPEND promised those things.
   (Includes updates to PCI and OMAP bus glue.)

 - Handle a not-noticed-before special case during resume from one of
   the swsusp snapshots when using "usb-handoff":  the controller isn't
   left in RESET state.  (A bug to fix in the usb-handoff code...)

Also cleans up a minor debug printk glitch, and switches an mdelay over
to an msleep (how did that stick around for so long?).
Signed-off-by: David Brownell <dbrownell@users.sourceforge.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

 drivers/usb/host/ohci-dbg.c  |    4 ----
 drivers/usb/host/ohci-hcd.c  |    2 +-
 drivers/usb/host/ohci-hub.c  |   42 ++++++++++++------------------------------
 drivers/usb/host/ohci-mem.c  |    1 -
 drivers/usb/host/ohci-omap.c |   36 ++++++++++++------------------------
 drivers/usb/host/ohci-pci.c  |   40 ++++++++--------------------------------
 drivers/usb/host/ohci.h      |    1 -
 7 files changed, 33 insertions(+), 93 deletions(-)

drivers/usb/host/ohci-dbg.c

@@ -193,10 +193,6 @@ ohci_dump_status (struct ohci_hcd *controller, char **next, unsigned *size)
 
 	maybe_print_eds (controller, "donehead",
 			ohci_readl (controller, &regs->donehead), next, size);
-
-	/* broken fminterval means traffic won't flow! */ 
-	ohci_dbg (controller, "fminterval %08x\n", 
-			ohci_readl (controller, &regs->fminterval));
 }
 
 #define dbg_port_sw(hc,num,value,next,size) \

drivers/usb/host/ohci-hcd.c

@@ -723,7 +723,7 @@ static irqreturn_t ohci_irq (struct usb_hcd *hcd, struct pt_regs *ptregs)
 		ohci_vdbg (ohci, "resume detect\n");
 		ohci_writel (ohci, OHCI_INTR_RD, &regs->intrstatus);
 		if (hcd->state != HC_STATE_QUIESCING)
-			schedule_work(&ohci->rh_resume);
+			usb_hcd_resume_root_hub(hcd);
 	}
 
 	if (ints & OHCI_INTR_WDH) {

drivers/usb/host/ohci-hub.c

@@ -73,7 +73,6 @@ static int ohci_hub_suspend (struct usb_hcd *hcd)
 	ohci_dbg (ohci, "suspend root hub\n");
 
 	/* First stop any processing */
-	hcd->state = HC_STATE_QUIESCING;
 	if (ohci->hc_control & OHCI_SCHED_ENABLES) {
 		int		limit;
 
@@ -108,7 +107,9 @@ static int ohci_hub_suspend (struct usb_hcd *hcd)
 	else
 		ohci->hc_control &= ~OHCI_CTRL_RWE;
 
-	/* Suspend hub */
+	/* Suspend hub ... this is the "global (to this bus) suspend" mode,
+	 * which doesn't imply ports will first be individually suspended.
+	 */
 	ohci->hc_control &= ~OHCI_CTRL_HCFS;
 	ohci->hc_control |= OHCI_USB_SUSPEND;
 	ohci_writel (ohci, ohci->hc_control, &ohci->regs->control);
@@ -118,8 +119,9 @@ static int ohci_hub_suspend (struct usb_hcd *hcd)
 	ohci->next_statechange = jiffies + msecs_to_jiffies (5);
 
 done:
+	/* external suspend vs self autosuspend ... same effect */
 	if (status == 0)
-		hcd->state = HC_STATE_SUSPENDED;
+		usb_hcd_suspend_root_hub(hcd);
 	spin_unlock_irqrestore (&ohci->lock, flags);
 	return status;
 }
@@ -146,7 +148,7 @@ static int ohci_hub_resume (struct usb_hcd *hcd)
 	ohci->hc_control = ohci_readl (ohci, &ohci->regs->control);
 
 	if (ohci->hc_control & (OHCI_CTRL_IR | OHCI_SCHED_ENABLES)) {
-		/* this can happen after suspend-to-disk */
+		/* this can happen after resuming a swsusp snapshot */
 		if (hcd->state == HC_STATE_RESUMING) {
 			ohci_dbg (ohci, "BIOS/SMM active, control %03x\n",
 					ohci->hc_control);
@@ -169,11 +171,12 @@ static int ohci_hub_resume (struct usb_hcd *hcd)
 		ohci_info (ohci, "wakeup\n");
 		break;
 	case OHCI_USB_OPER:
-		ohci_dbg (ohci, "already resumed\n");
-		status = 0;
+		/* this can happen after resuming a swsusp snapshot */
+		ohci_dbg (ohci, "snapshot resume? reinit\n");
+		status = -EBUSY;
 		break;
 	default:		/* RESET, we lost power */
-		ohci_dbg (ohci, "root hub hardware reset\n");
+		ohci_dbg (ohci, "lost power\n");
 		status = -EBUSY;
 	}
 	spin_unlock_irq (&ohci->lock);
@@ -198,8 +201,7 @@ static int ohci_hub_resume (struct usb_hcd *hcd)
 	}
 
 	/* Some controllers (lucent erratum) need extra-long delays */
-	hcd->state = HC_STATE_RESUMING;
-	mdelay (20 /* usb 11.5.1.10 */ + 15);
+	msleep (20 /* usb 11.5.1.10 */ + 12 /* 32 msec counter */ + 1);
 
 	temp = ohci_readl (ohci, &ohci->regs->control);
 	temp &= OHCI_CTRL_HCFS;
@@ -273,27 +275,9 @@ static int ohci_hub_resume (struct usb_hcd *hcd)
 		(void) ohci_readl (ohci, &ohci->regs->control);
 	}
 
-	hcd->state = HC_STATE_RUNNING;
 	return 0;
 }
 
-static void ohci_rh_resume (void *_hcd)
-{
-	struct usb_hcd	*hcd = _hcd;
-
-	usb_lock_device (hcd->self.root_hub);
-	(void) ohci_hub_resume (hcd);
-	usb_unlock_device (hcd->self.root_hub);
-}
-
-#else
-
-static void ohci_rh_resume (void *_hcd)
-{
-	struct ohci_hcd	*ohci = hcd_to_ohci (_hcd);
-	ohci_dbg(ohci, "rh_resume ??\n");
-}
-
 #endif	/* CONFIG_PM */
 
 /*-------------------------------------------------------------------------*/
@@ -367,7 +351,6 @@ ohci_hub_status_data (struct usb_hcd *hcd, char *buf)
 #ifdef CONFIG_PM
 	/* save power by suspending idle root hubs;
 	 * INTR_RD wakes us when there's work
-	 * NOTE: if we can do this, we don't need a root hub timer!
 	 */
 	if (can_suspend
 			&& !changed
@@ -380,7 +363,6 @@ ohci_hub_status_data (struct usb_hcd *hcd, char *buf)
 			) {
 		ohci_vdbg (ohci, "autosuspend\n");
 		(void) ohci_hub_suspend (hcd);
-		hcd->state = HC_STATE_RUNNING;
 		usb_unlock_device (hcd->self.root_hub);
 	}
 #endif
@@ -554,7 +536,7 @@ static int ohci_hub_control (
 			temp = RH_PS_POCI;
 			if ((ohci->hc_control & OHCI_CTRL_HCFS)
 					!= OHCI_USB_OPER)
-				schedule_work (&ohci->rh_resume);
+				usb_hcd_resume_root_hub(hcd);
 			break;
 		case USB_PORT_FEAT_C_SUSPEND:
 			temp = RH_PS_PSSC;

drivers/usb/host/ohci-mem.c

@@ -28,7 +28,6 @@ static void ohci_hcd_init (struct ohci_hcd *ohci)
 	ohci->next_statechange = jiffies;
 	spin_lock_init (&ohci->lock);
 	INIT_LIST_HEAD (&ohci->pending);
-	INIT_WORK (&ohci->rh_resume, ohci_rh_resume, ohci_to_hcd(ohci));
 	ohci->reboot_notifier.notifier_call = ohci_reboot;
 }
 

drivers/usb/host/ohci-omap.c

@@ -458,41 +458,29 @@ static int ohci_hcd_omap_drv_remove(struct device *dev)
 static int ohci_omap_suspend(struct device *dev, pm_message_t message)
 {
 	struct ohci_hcd	*ohci = hcd_to_ohci(dev_get_drvdata(dev));
-	int		status = -EINVAL;
-
-	down(&ohci_to_hcd(ohci)->self.root_hub->serialize);
-	status = ohci_hub_suspend(ohci_to_hcd(ohci));
-	if (status == 0) {
-		omap_ohci_clock_power(0);
-		ohci_to_hcd(ohci)->self.root_hub->state =
-			USB_STATE_SUSPENDED;
-		ohci_to_hcd(ohci)->state = HC_STATE_SUSPENDED;
-		dev->power.power_state = PMSG_SUSPEND;
-	}
-	up(&ohci_to_hcd(ohci)->self.root_hub->serialize);
-	return status;
+
+	if (time_before(jiffies, ohci->next_statechange))
+		msleep(5);
+	ohci->next_statechange = jiffies;
+
+	omap_ohci_clock_power(0);
+	ohci_to_hcd(ohci)->state = HC_STATE_SUSPENDED;
+	dev->power.power_state = PMSG_SUSPEND;
+	return 0;
 }
 
 static int ohci_omap_resume(struct device *dev)
 {
 	struct ohci_hcd	*ohci = hcd_to_ohci(dev_get_drvdata(dev));
-	int		status = 0;
 
 	if (time_before(jiffies, ohci->next_statechange))
 		msleep(5);
 	ohci->next_statechange = jiffies;
+
 	omap_ohci_clock_power(1);
-#ifdef	CONFIG_USB_SUSPEND
-	/* get extra cleanup even if remote wakeup isn't in use */
-	status = usb_resume_device(ohci_to_hcd(ohci)->self.root_hub);
-#else
-	down(&ohci_to_hcd(ohci)->self.root_hub->serialize);
-	status = ohci_hub_resume(ohci_to_hcd(ohci));
-	up(&ohci_to_hcd(ohci)->self.root_hub->serialize);
-#endif
-	if (status == 0)
-		dev->power.power_state = PMSG_ON;
-	return status;
+	dev->power.power_state = PMSG_ON;
+	usb_hcd_resume_root_hub(dev_get_drvdata(dev));
+	return 0;
 }
 
 #endif

drivers/usb/host/ohci-pci.c

@@ -112,23 +112,13 @@ ohci_pci_start (struct usb_hcd *hcd)
 
 static int ohci_pci_suspend (struct usb_hcd *hcd, pm_message_t message)
 {
-	struct ohci_hcd		*ohci = hcd_to_ohci (hcd);
-
-	/* suspend root hub, hoping it keeps power during suspend */
-	if (time_before (jiffies, ohci->next_statechange))
-		msleep (100);
-
-#ifdef	CONFIG_USB_SUSPEND
-	(void) usb_suspend_device (hcd->self.root_hub);
-#else
-	usb_lock_device (hcd->self.root_hub);
-	(void) ohci_hub_suspend (hcd);
-	usb_unlock_device (hcd->self.root_hub);
-#endif
+	/* root hub was already suspended */
 
-	/* let things settle down a bit */
-	msleep (100);
-	
+	/* FIXME these PMAC things get called in the wrong places.  ASIC
+	 * clocks should be turned off AFTER entering D3, and on BEFORE
+	 * trying to enter D0.  Evidently the PCI layer doesn't currently
+	 * provide the right sort of platform hooks for this ...
+	 */
 #ifdef CONFIG_PPC_PMAC
 	if (_machine == _MACH_Pmac) {
 	   	struct device_node	*of_node;
@@ -145,9 +135,6 @@ static int ohci_pci_suspend (struct usb_hcd *hcd, pm_message_t message)
 
 static int ohci_pci_resume (struct usb_hcd *hcd)
 {
-	struct ohci_hcd		*ohci = hcd_to_ohci (hcd);
-	int			retval = 0;
-
 #ifdef CONFIG_PPC_PMAC
 	if (_machine == _MACH_Pmac) {
 		struct device_node *of_node;
@@ -159,19 +146,8 @@ static int ohci_pci_resume (struct usb_hcd *hcd)
 	}
 #endif /* CONFIG_PPC_PMAC */
 
-	/* resume root hub */
-	if (time_before (jiffies, ohci->next_statechange))
-		msleep (100);
-#ifdef	CONFIG_USB_SUSPEND
-	/* get extra cleanup even if remote wakeup isn't in use */
-	retval = usb_resume_device (hcd->self.root_hub);
-#else
-	usb_lock_device (hcd->self.root_hub);
-	retval = ohci_hub_resume (hcd);
-	usb_unlock_device (hcd->self.root_hub);
-#endif
-
-	return retval;
+	usb_hcd_resume_root_hub(hcd);
+	return 0;
 }
 
 #endif	/* CONFIG_PM */

drivers/usb/host/ohci.h

@@ -389,7 +389,6 @@ struct ohci_hcd {
 	unsigned long		next_statechange;	/* suspend/resume */
 	u32			fminterval;		/* saved register */
 
-	struct work_struct	rh_resume;
 	struct notifier_block	reboot_notifier;
 
 	unsigned long		flags;		/* for HC bugs */