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-rw-r--r--drivers/usb/gadget/function/f_uvc.c39
-rw-r--r--drivers/usb/gadget/function/uvc.h3
-rw-r--r--drivers/usb/gadget/function/uvc_v4l2.c5
3 files changed, 43 insertions, 4 deletions
diff --git a/drivers/usb/gadget/function/f_uvc.c b/drivers/usb/gadget/function/f_uvc.c
index a96476507d2f..842187a09cc0 100644
--- a/drivers/usb/gadget/function/f_uvc.c
+++ b/drivers/usb/gadget/function/f_uvc.c
@@ -413,6 +413,12 @@ uvc_function_disconnect(struct uvc_device *uvc)
{
int ret;
+ guard(mutex)(&uvc->lock);
+ if (uvc->func_unbound) {
+ dev_dbg(&uvc->vdev.dev, "skipping function deactivate (unbound)\n");
+ return;
+ }
+
if ((ret = usb_function_deactivate(&uvc->func)) < 0)
uvcg_info(&uvc->func, "UVC disconnect failed with %d\n", ret);
}
@@ -431,6 +437,15 @@ static ssize_t function_name_show(struct device *dev,
static DEVICE_ATTR_RO(function_name);
+static void uvc_vdev_release(struct video_device *vdev)
+{
+ struct uvc_device *uvc = video_get_drvdata(vdev);
+
+ /* Signal uvc_function_unbind() that the video device has been released */
+ if (uvc->vdev_release_done)
+ complete(uvc->vdev_release_done);
+}
+
static int
uvc_register_video(struct uvc_device *uvc)
{
@@ -443,7 +458,7 @@ uvc_register_video(struct uvc_device *uvc)
uvc->vdev.v4l2_dev->dev = &cdev->gadget->dev;
uvc->vdev.fops = &uvc_v4l2_fops;
uvc->vdev.ioctl_ops = &uvc_v4l2_ioctl_ops;
- uvc->vdev.release = video_device_release_empty;
+ uvc->vdev.release = uvc_vdev_release;
uvc->vdev.vfl_dir = VFL_DIR_TX;
uvc->vdev.lock = &uvc->video.mutex;
uvc->vdev.device_caps = V4L2_CAP_VIDEO_OUTPUT | V4L2_CAP_STREAMING;
@@ -659,6 +674,8 @@ uvc_function_bind(struct usb_configuration *c, struct usb_function *f)
int ret = -EINVAL;
uvcg_info(f, "%s()\n", __func__);
+ scoped_guard(mutex, &uvc->lock)
+ uvc->func_unbound = false;
opts = fi_to_f_uvc_opts(f->fi);
/* Sanity check the streaming endpoint module parameters. */
@@ -988,12 +1005,19 @@ static void uvc_free(struct usb_function *f)
static void uvc_function_unbind(struct usb_configuration *c,
struct usb_function *f)
{
+ DECLARE_COMPLETION_ONSTACK(vdev_release_done);
struct usb_composite_dev *cdev = c->cdev;
struct uvc_device *uvc = to_uvc(f);
struct uvc_video *video = &uvc->video;
long wait_ret = 1;
+ bool connected;
uvcg_info(f, "%s()\n", __func__);
+ scoped_guard(mutex, &uvc->lock) {
+ uvc->func_unbound = true;
+ uvc->vdev_release_done = &vdev_release_done;
+ connected = uvc->func_connected;
+ }
kthread_cancel_work_sync(&video->hw_submit);
@@ -1006,7 +1030,7 @@ static void uvc_function_unbind(struct usb_configuration *c,
* though the video device removal uevent. Allow some time for the
* application to close out before things get deleted.
*/
- if (uvc->func_connected) {
+ if (connected) {
uvcg_dbg(f, "waiting for clean disconnect\n");
wait_ret = wait_event_interruptible_timeout(uvc->func_connected_queue,
uvc->func_connected == false, msecs_to_jiffies(500));
@@ -1017,7 +1041,10 @@ static void uvc_function_unbind(struct usb_configuration *c,
video_unregister_device(&uvc->vdev);
v4l2_device_unregister(&uvc->v4l2_dev);
- if (uvc->func_connected) {
+ scoped_guard(mutex, &uvc->lock)
+ connected = uvc->func_connected;
+
+ if (connected) {
/*
* Wait for the release to occur to ensure there are no longer any
* pending operations that may cause panics when resources are cleaned
@@ -1029,6 +1056,10 @@ static void uvc_function_unbind(struct usb_configuration *c,
uvcg_dbg(f, "done waiting for release with ret: %ld\n", wait_ret);
}
+ /* Wait for the video device to be released */
+ wait_for_completion(&vdev_release_done);
+ uvc->vdev_release_done = NULL;
+
usb_ep_free_request(cdev->gadget->ep0, uvc->control_req);
kfree(uvc->control_buf);
@@ -1047,6 +1078,8 @@ static struct usb_function *uvc_alloc(struct usb_function_instance *fi)
return ERR_PTR(-ENOMEM);
mutex_init(&uvc->video.mutex);
+ mutex_init(&uvc->lock);
+ uvc->func_unbound = true;
uvc->state = UVC_STATE_DISCONNECTED;
init_waitqueue_head(&uvc->func_connected_queue);
opts = fi_to_f_uvc_opts(fi);
diff --git a/drivers/usb/gadget/function/uvc.h b/drivers/usb/gadget/function/uvc.h
index 676419a04976..7abfdd5e1eef 100644
--- a/drivers/usb/gadget/function/uvc.h
+++ b/drivers/usb/gadget/function/uvc.h
@@ -155,6 +155,9 @@ struct uvc_device {
enum uvc_state state;
struct usb_function func;
struct uvc_video video;
+ struct completion *vdev_release_done;
+ struct mutex lock; /* protects func_unbound and func_connected */
+ bool func_unbound;
bool func_connected;
wait_queue_head_t func_connected_queue;
diff --git a/drivers/usb/gadget/function/uvc_v4l2.c b/drivers/usb/gadget/function/uvc_v4l2.c
index fd4b998ccd16..23bafb07133f 100644
--- a/drivers/usb/gadget/function/uvc_v4l2.c
+++ b/drivers/usb/gadget/function/uvc_v4l2.c
@@ -574,6 +574,8 @@ uvc_v4l2_subscribe_event(struct v4l2_fh *fh,
if (sub->type < UVC_EVENT_FIRST || sub->type > UVC_EVENT_LAST)
return -EINVAL;
+ guard(mutex)(&uvc->lock);
+
if (sub->type == UVC_EVENT_SETUP && uvc->func_connected)
return -EBUSY;
@@ -595,7 +597,8 @@ static void uvc_v4l2_disable(struct uvc_device *uvc)
uvc_function_disconnect(uvc);
uvcg_video_disable(&uvc->video);
uvcg_free_buffers(&uvc->video.queue);
- uvc->func_connected = false;
+ scoped_guard(mutex, &uvc->lock)
+ uvc->func_connected = false;
wake_up_interruptible(&uvc->func_connected_queue);
}