[PATCH 5/5] usb: xhci: Fix suspend/resume when used with OTG core

[Roger Quadros <rogerq@ti.com>]

In the OTG case, the controller might not yet have been
added or is removed before the system suspends.

Assign xhci->main_hcd during probe to prevent NULL
pointer de-reference in xhci_suspend/resume().

Use the hcd->state flag to check if HCD is halted
and if that is so do nothing for xhci_suspend/resume().

Signed-off-by: Roger Quadros <rogerq@ti.com>
---
 drivers/usb/host/xhci-pci.c  | 1 +
 drivers/usb/host/xhci-plat.c | 1 +
 drivers/usb/host/xhci.c      | 7 ++++++-
 3 files changed, 8 insertions(+), 1 deletion(-)

diff --git a/drivers/usb/host/xhci-pci.c b/drivers/usb/host/xhci-pci.c
index 4ad2c14..5474e0b 100644
--- a/drivers/usb/host/xhci-pci.c
+++ b/drivers/usb/host/xhci-pci.c
@@ -222,6 +222,7 @@ static int xhci_pci_probe(struct pci_dev *dev, const struct pci_device_id *id)
 	/* USB 2.0 roothub is stored in the PCI device now. */
 	hcd = dev_get_drvdata(&dev->dev);
 	xhci = hcd_to_xhci(hcd);
+	xhci->main_hcd = hcd;
 	xhci->shared_hcd = usb_create_shared_hcd(driver, &dev->dev,
 				pci_name(dev), hcd);
 	if (!xhci->shared_hcd) {
diff --git a/drivers/usb/host/xhci-plat.c b/drivers/usb/host/xhci-plat.c
index 00f23f5..68d67f5 100644
--- a/drivers/usb/host/xhci-plat.c
+++ b/drivers/usb/host/xhci-plat.c
@@ -140,6 +140,7 @@ static int xhci_plat_probe(struct platform_device *pdev)
 
 	xhci = hcd_to_xhci(hcd);
 	xhci->clk = clk;
+	xhci->main_hcd = hcd;
 	xhci->shared_hcd = usb_create_shared_hcd(driver, &pdev->dev,
 			dev_name(&pdev->dev), hcd);
 	if (!xhci->shared_hcd) {
diff --git a/drivers/usb/host/xhci.c b/drivers/usb/host/xhci.c
index 8a7e319..22ec235 100644
--- a/drivers/usb/host/xhci.c
+++ b/drivers/usb/host/xhci.c
@@ -891,6 +891,9 @@ int xhci_suspend(struct xhci_hcd *xhci, bool do_wakeup)
 	struct usb_hcd		*hcd = xhci_to_hcd(xhci);
 	u32			command;
 
+	if (!hcd->state)
+		return 0;
+
 	if (hcd->state != HC_STATE_SUSPENDED ||
 			xhci->shared_hcd->state != HC_STATE_SUSPENDED)
 		return -EINVAL;
@@ -977,6 +980,9 @@ int xhci_resume(struct xhci_hcd *xhci, bool hibernated)
 	int			retval = 0;
 	bool			comp_timer_running = false;
 
+	if (!hcd->state)
+		return 0;
+
 	/* Wait a bit if either of the roothubs need to settle from the
 	 * transition into bus suspend.
 	 */
@@ -4827,7 +4833,6 @@ int xhci_gen_setup(struct usb_hcd *hcd, xhci_get_quirks_t get_quirks)
 
 	if (usb_hcd_is_primary_hcd(hcd)) {
 		xhci = hcd_to_xhci(hcd);
-		xhci->main_hcd = hcd;
 		/* Mark the first roothub as being USB 2.0.
 		 * The xHCI driver will register the USB 3.0 roothub.
 		 */
-- 
2.1.0