On Fri Jul 25 13:12:48 2025 +0000, Ricardo Ribalda wrote:
> Since commit c93d73c9c2cf ("media: uvcvideo: Use vb2 ioctl and fop
> helpers"), the IOCTLs are serialized. Due to this there is no more need
> to protect ctrl, cur_format or cur_frame from concurrent access.
>
> Drop stream->mutex after thanking it for years of good service.
>
> Use this opportunity to do fix some CodeStyle.
>
> Signed-off-by: Ricardo Ribalda <[email protected]>
> Reviewed-by: Laurent Pinchart <[email protected]>
> Signed-off-by: Laurent Pinchart <[email protected]>
> Signed-off-by: Hans de Goede <[email protected]>
> Signed-off-by: Hans Verkuil <[email protected]>
Patch committed.
Thanks,
Hans Verkuil
drivers/media/usb/uvc/uvc_driver.c | 4 ----
drivers/media/usb/uvc/uvc_metadata.c | 10 +++------
drivers/media/usb/uvc/uvc_v4l2.c | 41 +++++++-----------------------------
drivers/media/usb/uvc/uvcvideo.h | 6 ------
4 files changed, 11 insertions(+), 50 deletions(-)
---
diff --git a/drivers/media/usb/uvc/uvc_driver.c
b/drivers/media/usb/uvc/uvc_driver.c
index 775bede0d93d..3039e6a533b8 100644
--- a/drivers/media/usb/uvc/uvc_driver.c
+++ b/drivers/media/usb/uvc/uvc_driver.c
@@ -183,8 +183,6 @@ static void uvc_stream_delete(struct uvc_streaming *stream)
if (stream->async_wq)
destroy_workqueue(stream->async_wq);
- mutex_destroy(&stream->mutex);
-
usb_put_intf(stream->intf);
kfree(stream->formats);
@@ -201,8 +199,6 @@ static struct uvc_streaming *uvc_stream_new(struct
uvc_device *dev,
if (stream == NULL)
return NULL;
- mutex_init(&stream->mutex);
-
stream->dev = dev;
stream->intf = usb_get_intf(intf);
stream->intfnum = intf->cur_altsetting->desc.bInterfaceNumber;
diff --git a/drivers/media/usb/uvc/uvc_metadata.c
b/drivers/media/usb/uvc/uvc_metadata.c
index b35111d08759..ed859ef4463d 100644
--- a/drivers/media/usb/uvc/uvc_metadata.c
+++ b/drivers/media/usb/uvc/uvc_metadata.c
@@ -99,16 +99,12 @@ static int uvc_meta_v4l2_set_format(struct file *file, void
*priv,
* Metadata buffers would still be perfectly parseable, but it's more
* consistent and cleaner to disallow that.
*/
- mutex_lock(&stream->mutex);
-
if (vb2_is_busy(&stream->meta.queue.queue))
- ret = -EBUSY;
- else
- stream->meta.format = fmt->dataformat;
+ return -EBUSY;
- mutex_unlock(&stream->mutex);
+ stream->meta.format = fmt->dataformat;
- return ret;
+ return 0;
}
static int uvc_meta_v4l2_enum_formats(struct file *file, void *priv,
diff --git a/drivers/media/usb/uvc/uvc_v4l2.c b/drivers/media/usb/uvc/uvc_v4l2.c
index f6e065f36ce0..e974aed93962 100644
--- a/drivers/media/usb/uvc/uvc_v4l2.c
+++ b/drivers/media/usb/uvc/uvc_v4l2.c
@@ -329,14 +329,12 @@ static int uvc_v4l2_try_format(struct uvc_streaming
*stream,
* developers test their webcams with the Linux driver as well as with
* the Windows driver).
*/
- mutex_lock(&stream->mutex);
if (stream->dev->quirks & UVC_QUIRK_PROBE_EXTRAFIELDS)
probe->dwMaxVideoFrameSize =
stream->ctrl.dwMaxVideoFrameSize;
/* Probe the device. */
ret = uvc_probe_video(stream, probe);
- mutex_unlock(&stream->mutex);
if (ret < 0)
return ret;
@@ -395,19 +393,15 @@ static int uvc_ioctl_g_fmt(struct file *file, void *priv,
struct uvc_streaming *stream = handle->stream;
const struct uvc_format *format;
const struct uvc_frame *frame;
- int ret = 0;
if (fmt->type != stream->type)
return -EINVAL;
- mutex_lock(&stream->mutex);
format = stream->cur_format;
frame = stream->cur_frame;
- if (format == NULL || frame == NULL) {
- ret = -EINVAL;
- goto done;
- }
+ if (!format || !frame)
+ return -EINVAL;
fmt->fmt.pix.pixelformat = format->fcc;
fmt->fmt.pix.width = frame->wWidth;
@@ -419,9 +413,7 @@ static int uvc_ioctl_g_fmt(struct file *file, void *priv,
fmt->fmt.pix.xfer_func = format->xfer_func;
fmt->fmt.pix.ycbcr_enc = format->ycbcr_enc;
-done:
- mutex_unlock(&stream->mutex);
- return ret;
+ return 0;
}
static int uvc_ioctl_s_fmt(struct file *file, void *priv,
@@ -441,19 +433,14 @@ static int uvc_ioctl_s_fmt(struct file *file, void *priv,
if (ret < 0)
return ret;
- mutex_lock(&stream->mutex);
- if (vb2_is_busy(&stream->queue.queue)) {
- ret = -EBUSY;
- goto done;
- }
+ if (vb2_is_busy(&stream->queue.queue))
+ return -EBUSY;
stream->ctrl = probe;
stream->cur_format = format;
stream->cur_frame = frame;
-done:
- mutex_unlock(&stream->mutex);
- return ret;
+ return 0;
}
static int uvc_ioctl_g_parm(struct file *file, void *priv,
@@ -466,10 +453,7 @@ static int uvc_ioctl_g_parm(struct file *file, void *priv,
if (parm->type != stream->type)
return -EINVAL;
- mutex_lock(&stream->mutex);
numerator = stream->ctrl.dwFrameInterval;
- mutex_unlock(&stream->mutex);
-
denominator = 10000000;
v4l2_simplify_fraction(&numerator, &denominator, 8, 333);
@@ -519,12 +503,8 @@ static int uvc_ioctl_s_parm(struct file *file, void *priv,
uvc_dbg(stream->dev, FORMAT, "Setting frame interval to %u/%u (%u)\n",
timeperframe.numerator, timeperframe.denominator, interval);
- mutex_lock(&stream->mutex);
-
- if (uvc_queue_streaming(&stream->queue)) {
- mutex_unlock(&stream->mutex);
+ if (uvc_queue_streaming(&stream->queue))
return -EBUSY;
- }
format = stream->cur_format;
frame = stream->cur_frame;
@@ -556,14 +536,11 @@ static int uvc_ioctl_s_parm(struct file *file, void *priv,
/* Probe the device with the new settings. */
ret = uvc_probe_video(stream, &probe);
- if (ret < 0) {
- mutex_unlock(&stream->mutex);
+ if (ret < 0)
return ret;
- }
stream->ctrl = probe;
stream->cur_frame = frame;
- mutex_unlock(&stream->mutex);
/* Return the actual frame period. */
timeperframe.numerator = probe.dwFrameInterval;
@@ -940,10 +917,8 @@ static int uvc_ioctl_g_selection(struct file *file, void
*priv,
sel->r.left = 0;
sel->r.top = 0;
- mutex_lock(&stream->mutex);
sel->r.width = stream->cur_frame->wWidth;
sel->r.height = stream->cur_frame->wHeight;
- mutex_unlock(&stream->mutex);
return 0;
}
diff --git a/drivers/media/usb/uvc/uvcvideo.h b/drivers/media/usb/uvc/uvcvideo.h
index 70dc80e2b213..678aa7a5e6b0 100644
--- a/drivers/media/usb/uvc/uvcvideo.h
+++ b/drivers/media/usb/uvc/uvcvideo.h
@@ -469,12 +469,6 @@ struct uvc_streaming {
const struct uvc_format *cur_format;
const struct uvc_frame *cur_frame;
- /*
- * Protect access to ctrl, cur_format, cur_frame and hardware video
- * probe control.
- */
- struct mutex mutex;
-
/* Buffers queue. */
unsigned int frozen : 1;
struct uvc_video_queue queue;
