xhci: quirk for extra long delay for S4

It has been reported that this chipset really cannot
sleep without this extraordinary delay.

This patch should be backported, in order to ensure this host functions
under stable kernels.  The last quirk for Fresco Logic hosts (commit
bba18e3 "xhci: Extend Fresco Logic MSI
quirk.") was backported to stable kernels as old as 2.6.36.

Signed-off-by: Oliver Neukum <[email protected]>
Signed-off-by: Sarah Sharp <[email protected]>
Cc: [email protected]

Author: Oliver Neukum

drivers/usb/host/xhci-pci.c

@@ -69,6 +69,14 @@ static void xhci_pci_quirks(struct device *dev, struct xhci_hcd *xhci)
 				"QUIRK: Fresco Logic xHC needs configure"
 				" endpoint cmd after reset endpoint");
 		}
+		if (pdev->device == PCI_DEVICE_ID_FRESCO_LOGIC_PDK &&
+				pdev->revision == 0x4) {
+			xhci->quirks |= XHCI_SLOW_SUSPEND;
+			xhci_dbg_trace(xhci, trace_xhci_dbg_quirks,
+				"QUIRK: Fresco Logic xHC revision %u"
+				"must be suspended extra slowly",
+				pdev->revision);
+		}
 		/* Fresco Logic confirms: all revisions of this chip do not
 		 * support MSI, even though some of them claim to in their PCI
 		 * capabilities.

drivers/usb/host/xhci.c

@@ -839,6 +839,7 @@ static void xhci_clear_command_ring(struct xhci_hcd *xhci)
 int xhci_suspend(struct xhci_hcd *xhci)
 {
 	int			rc = 0;
+	unsigned int		delay = XHCI_MAX_HALT_USEC;
 	struct usb_hcd		*hcd = xhci_to_hcd(xhci);
 	u32			command;
 
@@ -861,8 +862,12 @@ int xhci_suspend(struct xhci_hcd *xhci)
 	command = xhci_readl(xhci, &xhci->op_regs->command);
 	command &= ~CMD_RUN;
 	xhci_writel(xhci, command, &xhci->op_regs->command);
+
+	/* Some chips from Fresco Logic need an extraordinary delay */
+	delay *= (xhci->quirks & XHCI_SLOW_SUSPEND) ? 10 : 1;
+
 	if (xhci_handshake(xhci, &xhci->op_regs->status,
-		      STS_HALT, STS_HALT, XHCI_MAX_HALT_USEC)) {
+		      STS_HALT, STS_HALT, delay)) {
 		xhci_warn(xhci, "WARN: xHC CMD_RUN timeout\n");
 		spin_unlock_irq(&xhci->lock);
 		return -ETIMEDOUT;

drivers/usb/host/xhci.h

@@ -1548,6 +1548,7 @@ struct xhci_hcd {
 #define XHCI_COMP_MODE_QUIRK	(1 << 14)
 #define XHCI_AVOID_BEI		(1 << 15)
 #define XHCI_PLAT		(1 << 16)
+#define XHCI_SLOW_SUSPEND	(1 << 17)
 	unsigned int		num_active_eps;
 	unsigned int		limit_active_eps;
 	/* There are two roothubs to keep track of bus suspend info for */