[media] v4l2-ioctl: add ctrl_handler to v4l2_fh

This is required to implement control events and is also needed to allow
for per-filehandle control handlers.
Signed-off-by: Hans Verkuil <hverkuil@xs4all.nl>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>

drivers/media/video/v4l2-fh.c

@@ -32,6 +32,8 @@
 int v4l2_fh_init(struct v4l2_fh *fh, struct video_device *vdev)
 {
 	fh->vdev = vdev;
+	/* Inherit from video_device. May be overridden by the driver. */
+	fh->ctrl_handler = vdev->ctrl_handler;
 	INIT_LIST_HEAD(&fh->list);
 	set_bit(V4L2_FL_USES_V4L2_FH, &fh->vdev->flags);
 	fh->prio = V4L2_PRIORITY_UNSET;

drivers/media/video/v4l2-ioctl.c

@@ -1420,7 +1420,9 @@ static long __video_do_ioctl(struct file *file,
 	{
 		struct v4l2_queryctrl *p = arg;
 
-		if (vfd->ctrl_handler)
+		if (vfh && vfh->ctrl_handler)
+			ret = v4l2_queryctrl(vfh->ctrl_handler, p);
+		else if (vfd->ctrl_handler)
 			ret = v4l2_queryctrl(vfd->ctrl_handler, p);
 		else if (ops->vidioc_queryctrl)
 			ret = ops->vidioc_queryctrl(file, fh, p);
@@ -1440,7 +1442,9 @@ static long __video_do_ioctl(struct file *file,
 	{
 		struct v4l2_control *p = arg;
 
-		if (vfd->ctrl_handler)
+		if (vfh && vfh->ctrl_handler)
+			ret = v4l2_g_ctrl(vfh->ctrl_handler, p);
+		else if (vfd->ctrl_handler)
 			ret = v4l2_g_ctrl(vfd->ctrl_handler, p);
 		else if (ops->vidioc_g_ctrl)
 			ret = ops->vidioc_g_ctrl(file, fh, p);
@@ -1472,12 +1476,16 @@ static long __video_do_ioctl(struct file *file,
 		struct v4l2_ext_controls ctrls;
 		struct v4l2_ext_control ctrl;
 
-		if (!vfd->ctrl_handler &&
+		if (!(vfh && vfh->ctrl_handler) && !vfd->ctrl_handler &&
 			!ops->vidioc_s_ctrl && !ops->vidioc_s_ext_ctrls)
 			break;
 
 		dbgarg(cmd, "id=0x%x, value=%d\n", p->id, p->value);
 
+		if (vfh && vfh->ctrl_handler) {
+			ret = v4l2_s_ctrl(vfh->ctrl_handler, p);
+			break;
+		}
 		if (vfd->ctrl_handler) {
 			ret = v4l2_s_ctrl(vfd->ctrl_handler, p);
 			break;
@@ -1503,7 +1511,9 @@ static long __video_do_ioctl(struct file *file,
 		struct v4l2_ext_controls *p = arg;
 
 		p->error_idx = p->count;
-		if (vfd->ctrl_handler)
+		if (vfh && vfh->ctrl_handler)
+			ret = v4l2_g_ext_ctrls(vfh->ctrl_handler, p);
+		else if (vfd->ctrl_handler)
 			ret = v4l2_g_ext_ctrls(vfd->ctrl_handler, p);
 		else if (ops->vidioc_g_ext_ctrls && check_ext_ctrls(p, 0))
 			ret = ops->vidioc_g_ext_ctrls(file, fh, p);
@@ -1517,10 +1527,13 @@ static long __video_do_ioctl(struct file *file,
 		struct v4l2_ext_controls *p = arg;
 
 		p->error_idx = p->count;
-		if (!vfd->ctrl_handler && !ops->vidioc_s_ext_ctrls)
+		if (!(vfh && vfh->ctrl_handler) && !vfd->ctrl_handler &&
+				!ops->vidioc_s_ext_ctrls)
 			break;
 		v4l_print_ext_ctrls(cmd, vfd, p, 1);
-		if (vfd->ctrl_handler)
+		if (vfh && vfh->ctrl_handler)
+			ret = v4l2_s_ext_ctrls(vfh->ctrl_handler, p);
+		else if (vfd->ctrl_handler)
 			ret = v4l2_s_ext_ctrls(vfd->ctrl_handler, p);
 		else if (check_ext_ctrls(p, 0))
 			ret = ops->vidioc_s_ext_ctrls(file, fh, p);
@@ -1531,10 +1544,13 @@ static long __video_do_ioctl(struct file *file,
 		struct v4l2_ext_controls *p = arg;
 
 		p->error_idx = p->count;
-		if (!vfd->ctrl_handler && !ops->vidioc_try_ext_ctrls)
+		if (!(vfh && vfh->ctrl_handler) && !vfd->ctrl_handler &&
+				!ops->vidioc_try_ext_ctrls)
 			break;
 		v4l_print_ext_ctrls(cmd, vfd, p, 1);
-		if (vfd->ctrl_handler)
+		if (vfh && vfh->ctrl_handler)
+			ret = v4l2_try_ext_ctrls(vfh->ctrl_handler, p);
+		else if (vfd->ctrl_handler)
 			ret = v4l2_try_ext_ctrls(vfd->ctrl_handler, p);
 		else if (check_ext_ctrls(p, 0))
 			ret = ops->vidioc_try_ext_ctrls(file, fh, p);
@@ -1544,7 +1560,9 @@ static long __video_do_ioctl(struct file *file,
 	{
 		struct v4l2_querymenu *p = arg;
 
-		if (vfd->ctrl_handler)
+		if (vfh && vfh->ctrl_handler)
+			ret = v4l2_querymenu(vfh->ctrl_handler, p);
+		else if (vfd->ctrl_handler)
 			ret = v4l2_querymenu(vfd->ctrl_handler, p);
 		else if (ops->vidioc_querymenu)
 			ret = ops->vidioc_querymenu(file, fh, p);

include/media/v4l2-fh.h

@@ -30,11 +30,13 @@
 
 struct video_device;
 struct v4l2_events;
+struct v4l2_ctrl_handler;
 
 struct v4l2_fh {
 	struct list_head	list;
 	struct video_device	*vdev;
 	struct v4l2_events      *events; /* events, pending and subscribed */
+	struct v4l2_ctrl_handler *ctrl_handler;
 	enum v4l2_priority	prio;
 };