V4L/DVB: uvcvideo: Support menu controls in the control mapping API

The UVCIOC_CTRL_MAP ioctl doesn't support menu entries for menu
controls. As the uvc_xu_control_mapping structure has no reserved
fields, this can't be fixed while keeping ABI compatibility.

Modify the UVCIOC_CTRL_MAP ioctl to add menu entries support, and define
UVCIOC_CTRL_MAP_OLD that supports the old ABI without any ability to add
menu controls.

Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>

1 files changed, 69 insertions, 23 deletions

diff --git a/drivers/media/video/uvc/uvc_v4l2.c b/drivers/media/video/uvc/uvc_v4l2.c
index 7c9ab293349..485a89912ce 100644
--- a/drivers/media/video/uvc/uvc_v4l2.c
+++ b/drivers/media/video/uvc/uvc_v4l2.c
@@ -29,6 +29,71 @@
 #include "uvcvideo.h"
 
 /* ------------------------------------------------------------------------
+ * UVC ioctls
+ */
+static int uvc_ioctl_ctrl_map(struct uvc_xu_control_mapping *xmap, int old)
+{
+	struct uvc_control_mapping *map;
+	unsigned int size;
+	int ret;
+
+	map = kzalloc(sizeof *map, GFP_KERNEL);
+	if (map == NULL)
+		return -ENOMEM;
+
+	map->id = xmap->id;
+	memcpy(map->name, xmap->name, sizeof map->name);
+	memcpy(map->entity, xmap->entity, sizeof map->entity);
+	map->selector = xmap->selector;
+	map->size = xmap->size;
+	map->offset = xmap->offset;
+	map->v4l2_type = xmap->v4l2_type;
+	map->data_type = xmap->data_type;
+
+	switch (xmap->v4l2_type) {
+	case V4L2_CTRL_TYPE_INTEGER:
+	case V4L2_CTRL_TYPE_BOOLEAN:
+	case V4L2_CTRL_TYPE_BUTTON:
+		break;
+
+	case V4L2_CTRL_TYPE_MENU:
+		if (old) {
+			ret = -EINVAL;
+			goto done;
+		}
+
+		size = xmap->menu_count * sizeof(*map->menu_info);
+		map->menu_info = kmalloc(size, GFP_KERNEL);
+		if (map->menu_info == NULL) {
+			ret = -ENOMEM;
+			goto done;
+		}
+
+		if (copy_from_user(map->menu_info, xmap->menu_info, size)) {
+			ret = -EFAULT;
+			goto done;
+		}
+
+		map->menu_count = xmap->menu_count;
+		break;
+
+	default:
+		ret = -EINVAL;
+		goto done;
+	}
+
+	ret = uvc_ctrl_add_mapping(map);
+
+done:
+	if (ret < 0) {
+		kfree(map->menu_info);
+		kfree(map);
+	}
+
+	return ret;
+}
+
+/* ------------------------------------------------------------------------
  * V4L2 interface
  */
 
@@ -974,7 +1039,8 @@ static long uvc_v4l2_do_ioctl(struct file *file, unsigned int cmd, void *arg)
 		info->flags = xinfo->flags;
 
 		info->flags |= UVC_CONTROL_GET_MIN | UVC_CONTROL_GET_MAX |
-				UVC_CONTROL_GET_RES | UVC_CONTROL_GET_DEF;
+			       UVC_CONTROL_GET_RES | UVC_CONTROL_GET_DEF |
+			       UVC_CONTROL_EXTENSION;
 
 		ret = uvc_ctrl_add_info(info);
 		if (ret < 0)
@@ -982,32 +1048,12 @@ static long uvc_v4l2_do_ioctl(struct file *file, unsigned int cmd, void *arg)
 		break;
 	}
 
+	case UVCIOC_CTRL_MAP_OLD:
 	case UVCIOC_CTRL_MAP:
-	{
-		struct uvc_xu_control_mapping *xmap = arg;
-		struct uvc_control_mapping *map;
-
 		if (!capable(CAP_SYS_ADMIN))
 			return -EPERM;
 
-		map = kzalloc(sizeof *map, GFP_KERNEL);
-		if (map == NULL)
-			return -ENOMEM;
-
-		map->id = xmap->id;
-		memcpy(map->name, xmap->name, sizeof map->name);
-		memcpy(map->entity, xmap->entity, sizeof map->entity);
-		map->selector = xmap->selector;
-		map->size = xmap->size;
-		map->offset = xmap->offset;
-		map->v4l2_type = xmap->v4l2_type;
-		map->data_type = xmap->data_type;
-
-		ret = uvc_ctrl_add_mapping(map);
-		if (ret < 0)
-			kfree(map);
-		break;
-	}
+		return uvc_ioctl_ctrl_map(arg, cmd == UVCIOC_CTRL_MAP_OLD);
 
 	case UVCIOC_CTRL_GET:
 		return uvc_xu_ctrl_query(chain, arg, 0);