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media: uvcvideo: Recover stalled ElGato devices

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Elgato Cam Link 4k can be in a stalled state if the resolution of
the external source has changed while the firmware initializes.
Once in this state, the device is useless until it receives a
USB reset. It has even been observed that the stalled state will
continue even after unplugging the device.

lsusb -v

Bus 002 Device 002: ID 0fd9:0066 Elgato Systems GmbH Cam Link 4K
Device Descriptor:
  bLength                18
  bDescriptorType         1
  bcdUSB               3.00
  bDeviceClass          239 Miscellaneous Device
  bDeviceSubClass         2
  bDeviceProtocol         1 Interface Association
  bMaxPacketSize0         9
  idVendor           0x0fd9 Elgato Systems GmbH
  idProduct          0x0066
  bcdDevice            0.00
  iManufacturer           1 Elgato
  iProduct                2 Cam Link 4K
  iSerial                 4 0005AC52FE000
  bNumConfigurations      1

Reviewed-by: Sergey Senozhatsky <senozhatsky@chromium.org>
Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: Ricardo Ribalda <ribalda@chromium.org>
Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
This commit is contained in:
Ricardo Ribalda 2022-12-06 00:15:04 +01:00 committed by Laurent Pinchart
parent adfd3910c2
commit 16045708a3
1 changed files with 20 additions and 4 deletions
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24
drivers/media/usb/uvc/uvc_video.c
View File

@ -129,12 +129,13 @@ int uvc_query_ctrl(struct uvc_device *dev, u8 query, u8 unit,
return -EPIPE;
}
static const struct usb_device_id elgato_cam_link_4k = {
USB_DEVICE(0x0fd9, 0x0066)
};
static void uvc_fixup_video_ctrl(struct uvc_streaming *stream,
struct uvc_streaming_control *ctrl)
{
static const struct usb_device_id elgato_cam_link_4k = {
USB_DEVICE(0x0fd9, 0x0066)
};
struct uvc_format *format = NULL;
struct uvc_frame *frame = NULL;
unsigned int i;
@ -297,7 +298,7 @@ static int uvc_get_video_ctrl(struct uvc_streaming *stream,
dev_err(&stream->intf->dev,
"Failed to query (%u) UVC %s control : %d (exp. %u).\n",
query, probe ? "probe" : "commit", ret, size);
ret = -EIO;
ret = (ret == -EPROTO) ? -EPROTO : -EIO;
goto out;
}
@ -2121,6 +2122,21 @@ int uvc_video_init(struct uvc_streaming *stream)
* request on the probe control, as required by the UVC specification.
*/
ret = uvc_get_video_ctrl(stream, probe, 1, UVC_GET_CUR);
/*
* Elgato Cam Link 4k can be in a stalled state if the resolution of
* the external source has changed while the firmware initializes.
* Once in this state, the device is useless until it receives a
* USB reset. It has even been observed that the stalled state will
* continue even after unplugging the device.
*/
if (ret == -EPROTO &&
usb_match_one_id(stream->dev->intf, &elgato_cam_link_4k)) {
dev_err(&stream->intf->dev, "Elgato Cam Link 4K firmware crash detected\n");
dev_err(&stream->intf->dev, "Resetting the device, unplug and replug to recover\n");
usb_reset_device(stream->dev->udev);
}
if (ret < 0)
return ret;