From 23d9f3ef23f0dc4bb20ccd5540b9a91ff08da08f Mon Sep 17 00:00:00 2001 From: Laurent Pinchart Date: Sun, 21 Nov 2010 07:58:54 -0300 Subject: [PATCH] [media] uvcvideo: Lock controls mutex when querying menus uvc_find_control() must be called with the controls mutex locked. Fix uvc_query_v4l2_menu() accordingly. Signed-off-by: Laurent Pinchart Signed-off-by: Mauro Carvalho Chehab --- drivers/media/video/uvc/uvc_ctrl.c | 48 +++++++++++++++++++++++++++++- drivers/media/video/uvc/uvc_v4l2.c | 36 +--------------------- drivers/media/video/uvc/uvcvideo.h | 4 +-- 3 files changed, 50 insertions(+), 38 deletions(-) diff --git a/drivers/media/video/uvc/uvc_ctrl.c b/drivers/media/video/uvc/uvc_ctrl.c index f169f7736677..59f8a9ad3796 100644 --- a/drivers/media/video/uvc/uvc_ctrl.c +++ b/drivers/media/video/uvc/uvc_ctrl.c @@ -785,7 +785,7 @@ static void __uvc_find_control(struct uvc_entity *entity, __u32 v4l2_id, } } -struct uvc_control *uvc_find_control(struct uvc_video_chain *chain, +static struct uvc_control *uvc_find_control(struct uvc_video_chain *chain, __u32 v4l2_id, struct uvc_control_mapping **mapping) { struct uvc_control *ctrl = NULL; @@ -944,6 +944,52 @@ done: return ret; } +/* + * Mapping V4L2 controls to UVC controls can be straighforward if done well. + * Most of the UVC controls exist in V4L2, and can be mapped directly. Some + * must be grouped (for instance the Red Balance, Blue Balance and Do White + * Balance V4L2 controls use the White Balance Component UVC control) or + * otherwise translated. The approach we take here is to use a translation + * table for the controls that can be mapped directly, and handle the others + * manually. + */ +int uvc_query_v4l2_menu(struct uvc_video_chain *chain, + struct v4l2_querymenu *query_menu) +{ + struct uvc_menu_info *menu_info; + struct uvc_control_mapping *mapping; + struct uvc_control *ctrl; + u32 index = query_menu->index; + u32 id = query_menu->id; + int ret; + + memset(query_menu, 0, sizeof(*query_menu)); + query_menu->id = id; + query_menu->index = index; + + ret = mutex_lock_interruptible(&chain->ctrl_mutex); + if (ret < 0) + return -ERESTARTSYS; + + ctrl = uvc_find_control(chain, query_menu->id, &mapping); + if (ctrl == NULL || mapping->v4l2_type != V4L2_CTRL_TYPE_MENU) { + ret = -EINVAL; + goto done; + } + + if (query_menu->index >= mapping->menu_count) { + ret = -EINVAL; + goto done; + } + + menu_info = &mapping->menu_info[query_menu->index]; + strlcpy(query_menu->name, menu_info->name, sizeof query_menu->name); + +done: + mutex_unlock(&chain->ctrl_mutex); + return ret; +} + /* -------------------------------------------------------------------------- * Control transactions diff --git a/drivers/media/video/uvc/uvc_v4l2.c b/drivers/media/video/uvc/uvc_v4l2.c index 6d15de9b5204..0f865e97cf48 100644 --- a/drivers/media/video/uvc/uvc_v4l2.c +++ b/drivers/media/video/uvc/uvc_v4l2.c @@ -100,40 +100,6 @@ done: * V4L2 interface */ -/* - * Mapping V4L2 controls to UVC controls can be straighforward if done well. - * Most of the UVC controls exist in V4L2, and can be mapped directly. Some - * must be grouped (for instance the Red Balance, Blue Balance and Do White - * Balance V4L2 controls use the White Balance Component UVC control) or - * otherwise translated. The approach we take here is to use a translation - * table for the controls that can be mapped directly, and handle the others - * manually. - */ -static int uvc_v4l2_query_menu(struct uvc_video_chain *chain, - struct v4l2_querymenu *query_menu) -{ - struct uvc_menu_info *menu_info; - struct uvc_control_mapping *mapping; - struct uvc_control *ctrl; - u32 index = query_menu->index; - u32 id = query_menu->id; - - ctrl = uvc_find_control(chain, query_menu->id, &mapping); - if (ctrl == NULL || mapping->v4l2_type != V4L2_CTRL_TYPE_MENU) - return -EINVAL; - - if (query_menu->index >= mapping->menu_count) - return -EINVAL; - - memset(query_menu, 0, sizeof(*query_menu)); - query_menu->id = id; - query_menu->index = index; - - menu_info = &mapping->menu_info[query_menu->index]; - strlcpy(query_menu->name, menu_info->name, sizeof query_menu->name); - return 0; -} - /* * Find the frame interval closest to the requested frame interval for the * given frame format and size. This should be done by the device as part of @@ -624,7 +590,7 @@ static long uvc_v4l2_do_ioctl(struct file *file, unsigned int cmd, void *arg) } case VIDIOC_QUERYMENU: - return uvc_v4l2_query_menu(chain, arg); + return uvc_query_v4l2_menu(chain, arg); case VIDIOC_G_EXT_CTRLS: { diff --git a/drivers/media/video/uvc/uvcvideo.h b/drivers/media/video/uvc/uvcvideo.h index d97cf6d6a4f9..45209245244b 100644 --- a/drivers/media/video/uvc/uvcvideo.h +++ b/drivers/media/video/uvc/uvcvideo.h @@ -606,10 +606,10 @@ extern int uvc_status_suspend(struct uvc_device *dev); extern int uvc_status_resume(struct uvc_device *dev); /* Controls */ -extern struct uvc_control *uvc_find_control(struct uvc_video_chain *chain, - __u32 v4l2_id, struct uvc_control_mapping **mapping); extern int uvc_query_v4l2_ctrl(struct uvc_video_chain *chain, struct v4l2_queryctrl *v4l2_ctrl); +extern int uvc_query_v4l2_menu(struct uvc_video_chain *chain, + struct v4l2_querymenu *query_menu); extern int uvc_ctrl_add_mapping(struct uvc_video_chain *chain, const struct uvc_control_mapping *mapping); -- 2.34.1