usb/xhci: release xhci->lock during turning on/off usb port's acpi power resource...

When setting usb port's acpi power resource, there will be some xhci hub requests.
This will cause dead lock since xhci->lock has been held before setting acpi power
resource in the xhci_hub_control(). The usb_acpi_power_manageable() function might
fall into sleep so release xhci->lock before invoking it.

Signed-off-by: Lan Tianyu <tianyu.lan@intel.com>
Signed-off-by: Sarah Sharp <sarah.a.sharp@linux.intel.com>

diff --git a/drivers/usb/host/xhci-hub.c b/drivers/usb/host/xhci-hub.c
index aa90ad4..65d416c 100644 (file)
--- a/drivers/usb/host/xhci-hub.c
+++ b/drivers/usb/host/xhci-hub.c
@@ -809,11 +809,13 @@ int xhci_hub_control(struct usb_hcd *hcd, u16 typeReq, u16 wValue,
                        temp = xhci_readl(xhci, port_array[wIndex]);
                        xhci_dbg(xhci, "set port power, actual port %d status  = 0x%x\n", wIndex, temp);
 
+                       spin_unlock_irqrestore(&xhci->lock, flags);
                        temp = usb_acpi_power_manageable(hcd->self.root_hub,
                                        wIndex);
                        if (temp)
                                usb_acpi_set_power_state(hcd->self.root_hub,
                                                wIndex, true);
+                       spin_lock_irqsave(&xhci->lock, flags);
                        break;
                case USB_PORT_FEAT_RESET:
                        temp = (temp | PORT_RESET);
@@ -917,11 +919,13 @@ int xhci_hub_control(struct usb_hcd *hcd, u16 typeReq, u16 wValue,
                        xhci_writel(xhci, temp & ~PORT_POWER,
                                port_array[wIndex]);
 
+                       spin_unlock_irqrestore(&xhci->lock, flags);
                        temp = usb_acpi_power_manageable(hcd->self.root_hub,
                                        wIndex);
                        if (temp)
                                usb_acpi_set_power_state(hcd->self.root_hub,
                                                wIndex, false);
+                       spin_lock_irqsave(&xhci->lock, flags);
                        break;
                default:
                        goto error;