path: root/drivers/usb/core/hub.c
diff options
authorElric Fu <elricfu1@gmail.com>2012-03-26 21:16:02 +0800
committerSarah Sharp <sarah.a.sharp@linux.intel.com>2012-04-11 08:28:58 -0700
commitd8aec3dbdfd02627e198e7956ab4aaeba2a349fa (patch)
treede495a5bbd9f0399f3673ee9b00d69543a72630c /drivers/usb/core/hub.c
parentc7713e736526d8c9f6f87716fb90562a8ffaff2c (diff)
USB: fix bug of device descriptor got from superspeed device
When the Seagate Goflex USB3.0 device is attached to VIA xHCI host, sometimes the device will downgrade mode to high speed. By the USB analyzer, I found the device finished the link training process and worked at superspeed mode. But the device descriptor got from the device shows the device works at 2.1. It is very strange and seems like the device controller of Seagate Goflex has a little confusion. The first 8 bytes of device descriptor should be: 12 01 00 03 00 00 00 09 But the first 8 bytes of wrong device descriptor are: 12 01 10 02 00 00 00 40 The wrong device descriptor caused the initialization of mass storage failed. After a while, the device would be recognized as a high speed device and works fine. This patch will warm reset the device to fix the issue after finding the bcdUSB field of device descriptor isn't 0x0300 but the speed mode of device is superspeed. This patch should be backported to kernels as old as 3.2, or ones that contain the commit 75d7cf72ab9fa01dc70877aa5c68e8ef477229dc "usbcore: refine warm reset logic". Signed-off-by: Elric Fu <elricfu1@gmail.com> Acked-by: Andiry Xu <Andiry.Xu@amd.com> Acked-by: Sergei Shtylyov <sshtylyov@mvista.com> Signed-off-by: Sarah Sharp <sarah.a.sharp@linux.intel.com> Cc: stable@vger.kernel.org
Diffstat (limited to 'drivers/usb/core/hub.c')
1 files changed, 16 insertions, 0 deletions
diff --git a/drivers/usb/core/hub.c b/drivers/usb/core/hub.c
index 28664eb7f55..a2aa9d652c6 100644
--- a/drivers/usb/core/hub.c
+++ b/drivers/usb/core/hub.c
@@ -3163,6 +3163,22 @@ hub_port_init (struct usb_hub *hub, struct usb_device *udev, int port1,
if (retval)
goto fail;
+ /*
+ * Some superspeed devices have finished the link training process
+ * and attached to a superspeed hub port, but the device descriptor
+ * got from those devices show they aren't superspeed devices. Warm
+ * reset the port attached by the devices can fix them.
+ */
+ if ((udev->speed == USB_SPEED_SUPER) &&
+ (le16_to_cpu(udev->descriptor.bcdUSB) < 0x0300)) {
+ dev_err(&udev->dev, "got a wrong device descriptor, "
+ "warm reset device\n");
+ hub_port_reset(hub, port1, udev,
+ retval = -EINVAL;
+ goto fail;
+ }
if (udev->descriptor.bMaxPacketSize0 == 0xff ||
udev->speed == USB_SPEED_SUPER)
i = 512;