[media] v4l2-ioctl: add priority handling support

Drivers that use v4l2_fh can now use the core framework support of g/s_priority.

Signed-off-by: Hans Verkuil <hverkuil@xs4all.nl>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
diff --git a/drivers/media/video/v4l2-ioctl.c b/drivers/media/video/v4l2-ioctl.c
index db6ec38..3e6b6fa 100644
--- a/drivers/media/video/v4l2-ioctl.c
+++ b/drivers/media/video/v4l2-ioctl.c
@@ -24,6 +24,7 @@
 #include <media/v4l2-ctrls.h>
 #include <media/v4l2-fh.h>
 #include <media/v4l2-event.h>
+#include <media/v4l2-device.h>
 #include <media/v4l2-chip-ident.h>
 
 #define dbgarg(cmd, fmt, arg...) \
@@ -538,6 +539,7 @@
 	struct video_device *vfd = video_devdata(file);
 	const struct v4l2_ioctl_ops *ops = vfd->ioctl_ops;
 	void *fh = file->private_data;
+	struct v4l2_fh *vfh = NULL;
 	struct v4l2_format f_copy;
 	long ret = -EINVAL;
 
@@ -553,6 +555,43 @@
 		printk(KERN_CONT "\n");
 	}
 
+	if (test_bit(V4L2_FL_USES_V4L2_FH, &vfd->flags))
+		vfh = file->private_data;
+
+	if (vfh && !ops->vidioc_s_priority) {
+		switch (cmd) {
+		case VIDIOC_S_CTRL:
+		case VIDIOC_S_STD:
+		case VIDIOC_S_INPUT:
+		case VIDIOC_S_OUTPUT:
+		case VIDIOC_S_TUNER:
+		case VIDIOC_S_FREQUENCY:
+		case VIDIOC_S_FMT:
+		case VIDIOC_S_CROP:
+		case VIDIOC_S_AUDIO:
+		case VIDIOC_S_AUDOUT:
+		case VIDIOC_S_EXT_CTRLS:
+		case VIDIOC_S_FBUF:
+		case VIDIOC_S_PRIORITY:
+		case VIDIOC_S_DV_PRESET:
+		case VIDIOC_S_DV_TIMINGS:
+		case VIDIOC_S_JPEGCOMP:
+		case VIDIOC_S_MODULATOR:
+		case VIDIOC_S_PARM:
+		case VIDIOC_S_HW_FREQ_SEEK:
+		case VIDIOC_ENCODER_CMD:
+		case VIDIOC_OVERLAY:
+		case VIDIOC_REQBUFS:
+		case VIDIOC_STREAMON:
+		case VIDIOC_STREAMOFF:
+			ret = v4l2_prio_check(vfd->prio, vfh->prio);
+			if (ret)
+				goto exit_prio;
+			ret = -EINVAL;
+			break;
+		}
+	}
+
 	switch (cmd) {
 
 	/* --- capabilities ------------------------------------------ */
@@ -579,9 +618,12 @@
 	{
 		enum v4l2_priority *p = arg;
 
-		if (!ops->vidioc_g_priority)
-			break;
-		ret = ops->vidioc_g_priority(file, fh, p);
+		if (ops->vidioc_g_priority) {
+			ret = ops->vidioc_g_priority(file, fh, p);
+		} else if (vfh) {
+			*p = v4l2_prio_max(&vfd->v4l2_dev->prio);
+			ret = 0;
+		}
 		if (!ret)
 			dbgarg(cmd, "priority is %d\n", *p);
 		break;
@@ -590,10 +632,13 @@
 	{
 		enum v4l2_priority *p = arg;
 
-		if (!ops->vidioc_s_priority)
-			break;
+		if (!ops->vidioc_s_priority && vfh == NULL)
+				break;
 		dbgarg(cmd, "setting priority to %d\n", *p);
-		ret = ops->vidioc_s_priority(file, fh, *p);
+		if (ops->vidioc_s_priority)
+			ret = ops->vidioc_s_priority(file, fh, *p);
+		else
+			ret = v4l2_prio_change(&vfd->v4l2_dev->prio, &vfh->prio, *p);
 		break;
 	}
 
@@ -2138,13 +2183,18 @@
 	}
 	default:
 	{
+		bool valid_prio = true;
+
 		if (!ops->vidioc_default)
 			break;
-		ret = ops->vidioc_default(file, fh, cmd, arg);
+		if (vfh && !ops->vidioc_s_priority)
+			valid_prio = v4l2_prio_check(vfd->prio, vfh->prio) >= 0;
+		ret = ops->vidioc_default(file, fh, valid_prio, cmd, arg);
 		break;
 	}
 	} /* switch */
 
+exit_prio:
 	if (vfd->debug & V4L2_DEBUG_IOCTL_ARG) {
 		if (ret < 0) {
 			v4l_print_ioctl(vfd->name, cmd);