From: Oliver Neukum <oneu...@suse.de>
I have a device that times out if enumerated after being
switched on while connected. Increasing timeouts or retries
doesn't help. The device needs an additional reset.
Signed-off-by: Oliver Neukum <oli...@neukum.org>
---
drivers/usb/core/hub.c | 15 +++++++++++++++
1 file changed, 15 insertions(+)
diff --git a/drivers/usb/core/hub.c b/drivers/usb/core/hub.c
index 3489bf1..cf992de 100644
--- a/drivers/usb/core/hub.c
+++ b/drivers/usb/core/hub.c
@@ -4005,6 +4005,7 @@ hub_port_init (struct usb_hub *hub, struct usb_device
*udev, int port1,
enum usb_device_speed oldspeed = udev->speed;
const char *speed;
int devnum = udev->devnum;
+ bool second_reset = false;
/* root hub ports have a slightly longer reset period
* (from USB 2.0 spec, section 7.1.7.5)
@@ -4136,6 +4137,20 @@ hub_port_init (struct usb_hub *hub, struct usb_device
*udev, int port1,
USB_DT_DEVICE << 8, 0,
buf, GET_DESCRIPTOR_BUFSIZE,
initial_descriptor_timeout);
+
+ /*
+ * Some devices time out if they are powered on
+ * when already connected. They need a second
+ * reset.
+ */
+ if (r == -ETIMEDOUT && !second_reset) {
+ retval = hub_port_reset(hub, port1,
udev, delay, false);
+ second_reset = true;
+ if (retval < 0)
+ dev_err(&udev->dev,
+ "recovery from timeout
failed, error %d\n",
+ retval);
+ }
switch (buf->bMaxPacketSize0) {
case 8: case 16: case 32: case 64: case 255:
if (buf->bDescriptorType ==
--
1.8.4.5
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