Hi Ricardo, On Tue, Dec 06, 2022 at 12:15:04AM +0100, Ricardo Ribalda wrote: > 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@xxxxxxxxxxxx> > Reviewed-by: Laurent Pinchart <laurent.pinchart@xxxxxxxxxxxxxxxx> > Signed-off-by: Ricardo Ribalda <ribalda@xxxxxxxxxxxx> > --- > Recover stalled ElGato devices > > Just a resend of this hw fix. Taken in my tree, thanks. > To: Laurent Pinchart <laurent.pinchart@xxxxxxxxxxxxxxxx> > To: Mauro Carvalho Chehab <mchehab@xxxxxxxxxx> > Cc: linux-media@xxxxxxxxxxxxxxx > Cc: linux-kernel@xxxxxxxxxxxxxxx > Cc: Sergey Senozhatsky <senozhatsky@xxxxxxxxxxxx> > Cc: Yunke Cao <yunkec@xxxxxxxxxxxx> > --- > Changes in v4: > - Add Reviewed-by: Laurent > - Update error messages (Thanks Laurent!) > - Swap checks on if (Thanks Laurent) > - Link to v3: https://lore.kernel.org/r/20220920-resend-elgato-v3-0-57668054127f@xxxxxxxxxxxx > > Changes in v3: > - Add Reviewed-by: Sergey > - Improve identation (Thanks Sergey!) > - Link to v2: https://lore.kernel.org/r/20220920-resend-elgato-v2-0-06b48b3b486a@xxxxxxxxxxxx > > Changes in v2: > - Remove info from lsusb > - Link to v1: https://lore.kernel.org/r/20220920-resend-elgato-v1-0-8672a2380e3d@xxxxxxxxxxxx > --- > drivers/media/usb/uvc/uvc_video.c | 24 ++++++++++++++++++++---- > 1 file changed, 20 insertions(+), 4 deletions(-) > > diff --git a/drivers/media/usb/uvc/uvc_video.c b/drivers/media/usb/uvc/uvc_video.c > index 170a008f4006..ba7c159cb2a6 100644 > --- a/drivers/media/usb/uvc/uvc_video.c > +++ b/drivers/media/usb/uvc/uvc_video.c > @@ -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; > > > --- > base-commit: 521a547ced6477c54b4b0cc206000406c221b4d6 > change-id: 20220920-resend-elgato-a845482bdd02 -- Regards, Laurent Pinchart
