diff options
| -rw-r--r-- | drivers/media/usb/uvc/uvc_driver.c | 32 |
1 files changed, 32 insertions, 0 deletions
diff --git a/drivers/media/usb/uvc/uvc_driver.c b/drivers/media/usb/uvc/uvc_driver.c index e55cf02baad6..9a791d8ef200 100644 --- a/drivers/media/usb/uvc/uvc_driver.c +++ b/drivers/media/usb/uvc/uvc_driver.c @@ -1716,6 +1716,31 @@ static int uvc_scan_chain_forward(struct uvc_video_chain *chain, return -EINVAL; } + /* + * Some devices reference an output terminal as the + * source of extension units. This is incorrect, as + * output terminals only have an input pin, and thus + * can't be connected to any entity in the forward + * direction. The resulting topology would cause issues + * when registering the media controller graph. To + * avoid this problem, connect the extension unit to + * the source of the output terminal instead. + */ + if (UVC_ENTITY_IS_OTERM(entity)) { + struct uvc_entity *source; + + source = uvc_entity_by_id(chain->dev, + entity->baSourceID[0]); + if (!source) { + uvc_dbg(chain->dev, DESCR, + "Can't connect extension unit %u in chain\n", + forward->id); + break; + } + + forward->baSourceID[0] = source->id; + } + list_add_tail(&forward->chain, &chain->entities); if (!found) uvc_dbg_cont(PROBE, " (->"); @@ -1735,6 +1760,13 @@ static int uvc_scan_chain_forward(struct uvc_video_chain *chain, return -EINVAL; } + if (UVC_ENTITY_IS_OTERM(entity)) { + uvc_dbg(chain->dev, DESCR, + "Unsupported connection between output terminals %u and %u\n", + entity->id, forward->id); + break; + } + list_add_tail(&forward->chain, &chain->entities); if (!found) uvc_dbg_cont(PROBE, " (->"); |