[PATCHv2 2/2] v4l2-ioctl: improve cropcap handling

Hans Verkuil
2016-03-21T08:48:11Z

If cropcap is implemented, then call it first to fill in the pixel
aspect ratio. Don't return if cropcap returns ENOTTY or ENOIOCTLCMD,
in that case just assume a 1:1 pixel aspect ratio.

After cropcap was called, then overwrite bounds and defrect with the
g_selection result because the g_selection() result always has priority
over anything that vidioc_cropcap returns.

Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com>
---
drivers/media/v4l2-core/v4l2-ioctl.c | 35 +++++++++++++++++++++++++++--------
1 file changed, 27 insertions(+), 8 deletions(-)

diff --git a/drivers/media/v4l2-core/v4l2-ioctl.c b/drivers/media/v4l2-core/v4l2-ioctl.c
index 3cf8d3a..61eb810 100644
--- a/drivers/media/v4l2-core/v4l2-ioctl.c
+++ b/drivers/media/v4l2-core/v4l2-ioctl.c
@@ -2161,7 +2161,7 @@ static int v4l_cropcap(const struct v4l2_ioctl_ops *ops,
{
struct v4l2_cropcap *p = arg;
struct v4l2_selection s = { .type = p->type };
- int ret;
+ int ret = -ENOTTY;

if (ops->vidioc_g_selection == NULL) {
/*
@@ -2173,6 +2173,32 @@ static int v4l_cropcap(const struct v4l2_ioctl_ops *ops,
return -ENOTTY;
}

+ /*
+ * Let cropcap fill in the pixelaspect if cropcap is available.
+ * There is still no other way of obtaining this information.
+ */
+ if (ops->vidioc_cropcap) {
+ ret = ops->vidioc_cropcap(file, fh, p);
+
+ /*
+ * If cropcap reports that it isn't implemented,
+ * then just keep going.
+ */
+ if (ret && ret != -ENOTTY && ret != -ENOIOCTLCMD)
+ return ret;
+ }
+
+ if (ret) {
+ /*
+ * cropcap wasn't implemented, so assume a 1:1 pixel
+ * aspect ratio, otherwise keep what cropcap gave us.
+ */
+ p->pixelaspect.numerator = 1;
+ p->pixelaspect.denominator = 1;
+ }
+
+ /* Use g_selection() to fill in the bounds and defrect rectangles */
+
/* obtaining bounds */
if (V4L2_TYPE_IS_OUTPUT(p->type))
s.target = V4L2_SEL_TGT_COMPOSE_BOUNDS;
@@ -2195,13 +2221,6 @@ static int v4l_cropcap(const struct v4l2_ioctl_ops *ops,
return ret;
p->defrect = s.r;

- /* setting trivial pixelaspect */
- p->pixelaspect.numerator = 1;
- p->pixelaspect.denominator = 1;
-
- if (ops->vidioc_cropcap)
- return ops->vidioc_cropcap(file, fh, p);
-
return 0;
}

--
2.7.0