V4L/DVB (11661): v4l2-ioctl: Check buffer types using g_fmt instead of try_fmt

For a number of different ioctls, the v4l2-ioctl code checks that the
passed buffer type is supported by the driver.  It did this by checking
that the driver defined a method for the try_fmt handler for that buffer
type.  However, try_fmt is optional and a driver might not provide it even
though it does support that type.  So use g_fmt instead, since that isn't
optional.

This should fix a problem with VBI capture with saa7146.

Signed-off-by: Trent Piepho <xyzzy@speakeasy.org>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>

drivers/media/video/v4l2-ioctl.c

@@ -544,39 +544,39 @@ static int check_fmt(const struct v4l2_ioctl_ops *ops, enum v4l2_buf_type type)
 
 	switch (type) {
 	case V4L2_BUF_TYPE_VIDEO_CAPTURE:
-		if (ops->vidioc_try_fmt_vid_cap)
+		if (ops->vidioc_g_fmt_vid_cap)
 			return 0;
 		break;
 	case V4L2_BUF_TYPE_VIDEO_OVERLAY:
-		if (ops->vidioc_try_fmt_vid_overlay)
+		if (ops->vidioc_g_fmt_vid_overlay)
 			return 0;
 		break;
 	case V4L2_BUF_TYPE_VIDEO_OUTPUT:
-		if (ops->vidioc_try_fmt_vid_out)
+		if (ops->vidioc_g_fmt_vid_out)
 			return 0;
 		break;
 	case V4L2_BUF_TYPE_VIDEO_OUTPUT_OVERLAY:
-		if (ops->vidioc_try_fmt_vid_out_overlay)
+		if (ops->vidioc_g_fmt_vid_out_overlay)
 			return 0;
 		break;
 	case V4L2_BUF_TYPE_VBI_CAPTURE:
-		if (ops->vidioc_try_fmt_vbi_cap)
+		if (ops->vidioc_g_fmt_vbi_cap)
 			return 0;
 		break;
 	case V4L2_BUF_TYPE_VBI_OUTPUT:
-		if (ops->vidioc_try_fmt_vbi_out)
+		if (ops->vidioc_g_fmt_vbi_out)
 			return 0;
 		break;
 	case V4L2_BUF_TYPE_SLICED_VBI_CAPTURE:
-		if (ops->vidioc_try_fmt_sliced_vbi_cap)
+		if (ops->vidioc_g_fmt_sliced_vbi_cap)
 			return 0;
 		break;
 	case V4L2_BUF_TYPE_SLICED_VBI_OUTPUT:
-		if (ops->vidioc_try_fmt_sliced_vbi_out)
+		if (ops->vidioc_g_fmt_sliced_vbi_out)
 			return 0;
 		break;
 	case V4L2_BUF_TYPE_PRIVATE:
-		if (ops->vidioc_try_fmt_type_private)
+		if (ops->vidioc_g_fmt_type_private)
 			return 0;
 		break;
 	}