USB: OHCI: fix problem with global suspend on ATI controllers

Some OHCI controllers from ATI/AMD seem to have difficulty with "global" USB suspend, that is, suspending an entire USB bus without setting the suspend feature for each port connected to a device. When we try to resume the child devices, the controller gives timeout errors on the unsuspended ports, requiring resets, and can even cause ohci-hcd to hang; see http://marc.info/?l=linux-usb&m=139514332820398&w=2 and the following messages. This patch fixes the problem by adding a new quirk flag to ohci-hcd. The flag causes the ohci_rh_suspend() routine to suspend each unsuspended, enabled port before suspending the root hub. This effectively converts the "global" suspend to an ordinary root-hub suspend. There is no need to unsuspend these ports when the root hub is resumed, because the child devices will be resumed anyway in the course of a normal system resume ("global" suspend is never used for runtime PM). This patch should be applied to all stable kernels which include commit 0aa2832 (USB: use "global suspend" for system sleep on USB-2 buses) or a backported version thereof. Signed-off-by: Alan Stern <[email protected]> Reported-by: Peter Münster <[email protected]> Tested-by: Peter Münster <[email protected]> CC: <[email protected]> Signed-off-by: Greg Kroah-Hartman <[email protected]>
SKAPUSTIANSKYI · May 3, 2014 · c1db30a · c1db30a
1 parent 4dd7aa0
commit c1db30a
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diff --git a/drivers/usb/host/ohci-hub.c b/drivers/usb/host/ohci-hub.c
@@ -90,6 +90,24 @@ __acquires(ohci->lock)
 	dl_done_list (ohci);
 	finish_unlinks (ohci, ohci_frame_no(ohci));
 
+	/*
+	 * Some controllers don't handle "global" suspend properly if
+	 * there are unsuspended ports.  For these controllers, put all
+	 * the enabled ports into suspend before suspending the root hub.
+	 */
+	if (ohci->flags & OHCI_QUIRK_GLOBAL_SUSPEND) {
+		__hc32 __iomem	*portstat = ohci->regs->roothub.portstatus;
+		int		i;
+		unsigned	temp;
+
+		for (i = 0; i < ohci->num_ports; (++i, ++portstat)) {
+			temp = ohci_readl(ohci, portstat);
+			if ((temp & (RH_PS_PES | RH_PS_PSS)) ==
+					RH_PS_PES)
+				ohci_writel(ohci, RH_PS_PSS, portstat);
+		}
+	}
+
 	/* maybe resume can wake root hub */
 	if (ohci_to_hcd(ohci)->self.root_hub->do_remote_wakeup || autostop) {
 		ohci->hc_control |= OHCI_CTRL_RWE;

diff --git a/drivers/usb/host/ohci-pci.c b/drivers/usb/host/ohci-pci.c
@@ -160,6 +160,7 @@ static int ohci_quirk_amd700(struct usb_hcd *hcd)
 		ohci_dbg(ohci, "enabled AMD prefetch quirk\n");
 	}
 
+	ohci->flags |= OHCI_QUIRK_GLOBAL_SUSPEND;
 	return 0;
 }
 

diff --git a/drivers/usb/host/ohci.h b/drivers/usb/host/ohci.h
@@ -405,6 +405,8 @@ struct ohci_hcd {
 #define	OHCI_QUIRK_HUB_POWER	0x100			/* distrust firmware power/oc setup */
 #define	OHCI_QUIRK_AMD_PLL	0x200			/* AMD PLL quirk*/
 #define	OHCI_QUIRK_AMD_PREFETCH	0x400			/* pre-fetch for ISO transfer */
+#define	OHCI_QUIRK_GLOBAL_SUSPEND	0x800		/* must suspend ports */
+
 	// there are also chip quirks/bugs in init logic
 
 	struct work_struct	nec_work;	/* Worker for NEC quirk */
-Original file line number
+Diff line change
@@ Expand Up / @@ -160,6 +160,7 @@ static int ohci_quirk_amd700(struct usb_hcd *hcd) @@
     		ohci_dbg(ohci, "enabled AMD prefetch quirk\n");
     	}
+    	ohci->flags |= OHCI_QUIRK_GLOBAL_SUSPEND;
     	return 0;
     }
@@ Expand Down @@