diff options
| author | Laurent Pinchart <laurent.pinchart@ideasonboard.com> | 2012-05-11 14:55:59 +0200 |
|---|---|---|
| committer | Mauro Carvalho Chehab <mchehab@redhat.com> | 2012-05-20 15:41:18 +0200 |
| commit | 6b363f9f97af10767e72a04c2a5cabfc32133cc4 (patch) | |
| tree | 32d455374f612d6f7b9416678c199733b11117cf /drivers/media/video/uvc | |
| parent | [media] au0828: Add USB ID used by many dongles (diff) | |
| download | linux-6b363f9f97af10767e72a04c2a5cabfc32133cc4.tar.xz linux-6b363f9f97af10767e72a04c2a5cabfc32133cc4.zip | |
[media] uvcvideo: Fix V4L2 button controls that share the same UVC control
The Logitech pan/tilt reset UVC control contains two V4L2 button
controls to reset pan and tilt. As the UVC control is not marked as
auto-update, the button bits are set but never reset. A pan reset that
follows a tilt reset would thus reset both pan and tilt.
Fix this by not caching the control value of write-only controls. All
standard UVC controls are either readable or auto-update, so this will
not cause any regression and will not result in extra USB requests.
Reported-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Acked-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
Diffstat (limited to 'drivers/media/video/uvc')
| -rw-r--r-- | drivers/media/video/uvc/uvc_ctrl.c | 7 |
1 files changed, 5 insertions, 2 deletions
diff --git a/drivers/media/video/uvc/uvc_ctrl.c b/drivers/media/video/uvc/uvc_ctrl.c index f3bd66c500b6..af26bbe6f76e 100644 --- a/drivers/media/video/uvc/uvc_ctrl.c +++ b/drivers/media/video/uvc/uvc_ctrl.c @@ -1351,9 +1351,12 @@ static int uvc_ctrl_commit_entity(struct uvc_device *dev, /* Reset the loaded flag for auto-update controls that were * marked as loaded in uvc_ctrl_get/uvc_ctrl_set to prevent - * uvc_ctrl_get from using the cached value. + * uvc_ctrl_get from using the cached value, and for write-only + * controls to prevent uvc_ctrl_set from setting bits not + * explicitly set by the user. */ - if (ctrl->info.flags & UVC_CTRL_FLAG_AUTO_UPDATE) + if (ctrl->info.flags & UVC_CTRL_FLAG_AUTO_UPDATE || + !(ctrl->info.flags & UVC_CTRL_FLAG_GET_CUR)) ctrl->loaded = 0; if (!ctrl->dirty) |