From: Guenter Roeck linux@roeck-us.net
[ Upstream commit 4867bb590ae445bcfaa711a86b603c97e94574b3 ]
On a Webcam from Quanta, we see the following error.
usb 3-5: New USB device found, idVendor=0408, idProduct=30d2, bcdDevice= 0.03 usb 3-5: New USB device strings: Mfr=3, Product=1, SerialNumber=2 usb 3-5: Product: USB2.0 HD UVC WebCam usb 3-5: Manufacturer: Quanta usb 3-5: SerialNumber: 0x0001 ... uvcvideo: Found UVC 1.10 device USB2.0 HD UVC WebCam (0408:30d2) uvcvideo: Failed to initialize entity for entity 5 uvcvideo: Failed to register entities (-22).
The Webcam reports an entity of type UVC_VC_EXTENSION_UNIT. It reports a string index of '7' associated with that entity. The attempt to read that string from the camera fails with error -32 (-EPIPE). usb_string() returns that error, but it is ignored. As result, the entity name is empty. This later causes v4l2_device_register_subdev() to return -EINVAL, and no entities are registered as result.
While this appears to be a firmware problem with the camera, the kernel should still handle the situation gracefully. To do that, check the return value from usb_string(). If it reports an error, assign the entity's default name.
Signed-off-by: Guenter Roeck linux@roeck-us.net Reviewed-by: Laurent Pinchart laurent.pinchart@ideasonboard.com Signed-off-by: Laurent Pinchart laurent.pinchart@ideasonboard.com Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/media/usb/uvc/uvc_driver.c | 48 ++++++++++++------------------ 1 file changed, 19 insertions(+), 29 deletions(-)
diff --git a/drivers/media/usb/uvc/uvc_driver.c b/drivers/media/usb/uvc/uvc_driver.c index 7e02b158a8c9d..de32985f235fc 100644 --- a/drivers/media/usb/uvc/uvc_driver.c +++ b/drivers/media/usb/uvc/uvc_driver.c @@ -1131,10 +1131,8 @@ static int uvc_parse_vendor_control(struct uvc_device *dev, + n; memcpy(unit->extension.bmControls, &buffer[23+p], 2*n);
- if (buffer[24+p+2*n] != 0) - usb_string(udev, buffer[24+p+2*n], unit->name, - sizeof(unit->name)); - else + if (buffer[24+p+2*n] == 0 || + usb_string(udev, buffer[24+p+2*n], unit->name, sizeof(unit->name)) < 0) sprintf(unit->name, "Extension %u", buffer[3]);
list_add_tail(&unit->list, &dev->entities); @@ -1258,15 +1256,15 @@ static int uvc_parse_standard_control(struct uvc_device *dev, memcpy(term->media.bmTransportModes, &buffer[10+n], p); }
- if (buffer[7] != 0) - usb_string(udev, buffer[7], term->name, - sizeof(term->name)); - else if (UVC_ENTITY_TYPE(term) == UVC_ITT_CAMERA) - sprintf(term->name, "Camera %u", buffer[3]); - else if (UVC_ENTITY_TYPE(term) == UVC_ITT_MEDIA_TRANSPORT_INPUT) - sprintf(term->name, "Media %u", buffer[3]); - else - sprintf(term->name, "Input %u", buffer[3]); + if (buffer[7] == 0 || + usb_string(udev, buffer[7], term->name, sizeof(term->name)) < 0) { + if (UVC_ENTITY_TYPE(term) == UVC_ITT_CAMERA) + sprintf(term->name, "Camera %u", buffer[3]); + if (UVC_ENTITY_TYPE(term) == UVC_ITT_MEDIA_TRANSPORT_INPUT) + sprintf(term->name, "Media %u", buffer[3]); + else + sprintf(term->name, "Input %u", buffer[3]); + }
list_add_tail(&term->list, &dev->entities); break; @@ -1298,10 +1296,8 @@ static int uvc_parse_standard_control(struct uvc_device *dev,
memcpy(term->baSourceID, &buffer[7], 1);
- if (buffer[8] != 0) - usb_string(udev, buffer[8], term->name, - sizeof(term->name)); - else + if (buffer[8] == 0 || + usb_string(udev, buffer[8], term->name, sizeof(term->name)) < 0) sprintf(term->name, "Output %u", buffer[3]);
list_add_tail(&term->list, &dev->entities); @@ -1323,10 +1319,8 @@ static int uvc_parse_standard_control(struct uvc_device *dev,
memcpy(unit->baSourceID, &buffer[5], p);
- if (buffer[5+p] != 0) - usb_string(udev, buffer[5+p], unit->name, - sizeof(unit->name)); - else + if (buffer[5+p] == 0 || + usb_string(udev, buffer[5+p], unit->name, sizeof(unit->name)) < 0) sprintf(unit->name, "Selector %u", buffer[3]);
list_add_tail(&unit->list, &dev->entities); @@ -1356,10 +1350,8 @@ static int uvc_parse_standard_control(struct uvc_device *dev, if (dev->uvc_version >= 0x0110) unit->processing.bmVideoStandards = buffer[9+n];
- if (buffer[8+n] != 0) - usb_string(udev, buffer[8+n], unit->name, - sizeof(unit->name)); - else + if (buffer[8+n] == 0 || + usb_string(udev, buffer[8+n], unit->name, sizeof(unit->name)) < 0) sprintf(unit->name, "Processing %u", buffer[3]);
list_add_tail(&unit->list, &dev->entities); @@ -1387,10 +1379,8 @@ static int uvc_parse_standard_control(struct uvc_device *dev, unit->extension.bmControls = (u8 *)unit + sizeof(*unit); memcpy(unit->extension.bmControls, &buffer[23+p], n);
- if (buffer[23+p+n] != 0) - usb_string(udev, buffer[23+p+n], unit->name, - sizeof(unit->name)); - else + if (buffer[23+p+n] == 0 || + usb_string(udev, buffer[23+p+n], unit->name, sizeof(unit->name)) < 0) sprintf(unit->name, "Extension %u", buffer[3]);
list_add_tail(&unit->list, &dev->entities);