diff options
| author | Avichal Rakesh <arakesh@google.com> | 2023-11-08 16:41:01 -0800 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2023-11-23 12:32:44 +0000 |
| commit | 991544dc579b636e69defa3eec486fd6f6191e59 (patch) | |
| tree | b326981f130ba8fc726afe171718f993a7d124af /drivers/usb/gadget/function/uvc_v4l2.c | |
| parent | 5a1ccf0c72cf917ff3ccc131d1bb8d19338ffe52 (diff) | |
usb: gadget: uvc: prevent use of disabled endpoint
Currently the set_alt callback immediately disables the endpoint and queues
the v4l2 streamoff event. However, as the streamoff event is processed
asynchronously, it is possible that the video_pump thread attempts to queue
requests to an already disabled endpoint.
This change moves disabling usb endpoint to the end of streamoff event
callback. As the endpoint's state can no longer be used, video_pump is
now guarded by uvc->state as well. To be consistent with the actual
streaming state, uvc->state is now toggled between CONNECTED and STREAMING
from the v4l2 event callback only.
Link: https://lore.kernel.org/20230615171558.GK741@pendragon.ideasonboard.com/
Link: https://lore.kernel.org/20230531085544.253363-1-dan.scally@ideasonboard.com/
Reviewed-by: Daniel Scally <dan.scally@ideasonboard.com>
Reviewed-by: Michael Grzeschik <m.grzeschik@pengutronix.de>
Tested-by: Michael Grzeschik <m.grzeschik@pengutronix.de>
Signed-off-by: Avichal Rakesh <arakesh@google.com>
Link: https://lore.kernel.org/r/20231109004104.3467968-1-arakesh@google.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'drivers/usb/gadget/function/uvc_v4l2.c')
| -rw-r--r-- | drivers/usb/gadget/function/uvc_v4l2.c | 20 |
1 files changed, 17 insertions, 3 deletions
diff --git a/drivers/usb/gadget/function/uvc_v4l2.c b/drivers/usb/gadget/function/uvc_v4l2.c index 3f0a9795c0d4..7cb8d027ff0c 100644 --- a/drivers/usb/gadget/function/uvc_v4l2.c +++ b/drivers/usb/gadget/function/uvc_v4l2.c @@ -451,7 +451,7 @@ uvc_v4l2_streamon(struct file *file, void *fh, enum v4l2_buf_type type) * Complete the alternate setting selection setup phase now that * userspace is ready to provide video frames. */ - uvc_function_setup_continue(uvc); + uvc_function_setup_continue(uvc, 0); uvc->state = UVC_STATE_STREAMING; return 0; @@ -463,11 +463,18 @@ uvc_v4l2_streamoff(struct file *file, void *fh, enum v4l2_buf_type type) struct video_device *vdev = video_devdata(file); struct uvc_device *uvc = video_get_drvdata(vdev); struct uvc_video *video = &uvc->video; + int ret = 0; if (type != video->queue.queue.type) return -EINVAL; - return uvcg_video_enable(video, 0); + uvc->state = UVC_STATE_CONNECTED; + ret = uvcg_video_enable(video, 0); + if (ret < 0) + return ret; + + uvc_function_setup_continue(uvc, 1); + return 0; } static int @@ -500,6 +507,14 @@ uvc_v4l2_subscribe_event(struct v4l2_fh *fh, static void uvc_v4l2_disable(struct uvc_device *uvc) { uvc_function_disconnect(uvc); + /* + * Drop uvc->state to CONNECTED if it was streaming before. + * This ensures that the usb_requests are no longer queued + * to the controller. + */ + if (uvc->state == UVC_STATE_STREAMING) + uvc->state = UVC_STATE_CONNECTED; + uvcg_video_enable(&uvc->video, 0); uvcg_free_buffers(&uvc->video.queue); uvc->func_connected = false; @@ -647,4 +662,3 @@ const struct v4l2_file_operations uvc_v4l2_fops = { .get_unmapped_area = uvcg_v4l2_get_unmapped_area, #endif }; - |