xhci: Avoid dead ports when CONFIG_USB_XHCI_HCD=n
If the user chooses to say "no" to CONFIG_USB_XHCI_HCD on a system
with an Intel Panther Point chipset, the PCI quirks code or the EHCI
driver will switch the ports over to the xHCI host, but the xHCI driver
will never load. The ports will be powered off and seem "dead" to the
user.
Fix this by only switching the ports over if CONFIG_USB_XHCI_HCD is
either compiled in, or compiled as a module.
This patch should be backported to the 3.0 stable kernel, since it
contains the commit 69e848c2090aebba5698a1620604c7dccb448684 "Intel
xhci: Support EHCI/xHCI port switching."
Signed-off-by: Sarah Sharp <sarah.a.sharp@linux.intel.com>
Reported-by: Eric Anholt <eric.anholt@intel.com>
Reported-by: David Bein <d.bein@f5.com>
Cc: stable@vger.kernel.org
diff --git a/drivers/usb/host/pci-quirks.c b/drivers/usb/host/pci-quirks.c
index 0757b19..d0cf708 100644
--- a/drivers/usb/host/pci-quirks.c
+++ b/drivers/usb/host/pci-quirks.c
@@ -757,6 +757,7 @@
{
u32 ports_available;
+#if defined(CONFIG_USB_XHCI_HCD) || defined(CONFIG_USB_XHCI_HCD_MODULE)
ports_available = 0xffffffff;
/* Write USB3_PSSEN, the USB 3.0 Port SuperSpeed Enable
* Register, to turn on SuperSpeed terminations for all
@@ -782,6 +783,20 @@
&ports_available);
dev_dbg(&xhci_pdev->dev, "USB 2.0 ports that are now switched over "
"to xHCI: 0x%x\n", ports_available);
+#else
+ /* Don't switchover the ports if the user hasn't compiled the xHCI
+ * driver. Otherwise they will see "dead" USB ports that don't power
+ * the devices.
+ */
+ if (!IS_ENABLED(CONFIG_USB_XHCI_HCD)) {
+ dev_warn(&xhci_pdev->dev,
+ "CONFIG_USB_XHCI_HCD is turned off, "
+ "defaulting to EHCI.\n");
+ dev_warn(&xhci_pdev->dev,
+ "USB 3.0 devices will work at USB 2.0 speeds.\n");
+ }
+#endif /* CONFIG_USB_XHCI_HCD || CONFIG_USB_XHCI_HCD_MODULE */
+
}
EXPORT_SYMBOL_GPL(usb_enable_xhci_ports);
