On 14/02/18 16:50, Mauro Carvalho Chehab wrote:
> Em Mon, 22 Jan 2018 13:31:17 +0100
> Hans Verkuil <hverk...@xs4all.nl> escreveu:
>
>> From: Hans Verkuil <hans.verk...@cisco.com>
>>
>> Create helpers to handle VIDIOC_G/S_PARM by querying the
>> g/s_frame_interval v4l2_subdev ops.
>>
>> Signed-off-by: Hans Verkuil <hans.verk...@cisco.com>
>> ---
>> drivers/media/v4l2-core/v4l2-common.c | 48
>> +++++++++++++++++++++++++++++++++++
>> include/media/v4l2-common.h | 26 +++++++++++++++++++
>> 2 files changed, 74 insertions(+)
>>
>> diff --git a/drivers/media/v4l2-core/v4l2-common.c
>> b/drivers/media/v4l2-core/v4l2-common.c
>> index 8650ad92b64d..96c1b31de9e3 100644
>> --- a/drivers/media/v4l2-core/v4l2-common.c
>> +++ b/drivers/media/v4l2-core/v4l2-common.c
>> @@ -392,3 +392,51 @@ void v4l2_get_timestamp(struct timeval *tv)
>> tv->tv_usec = ts.tv_nsec / NSEC_PER_USEC;
>> }
>> EXPORT_SYMBOL_GPL(v4l2_get_timestamp);
>> +
>> +int v4l2_g_parm_cap(struct video_device *vdev,
>> + struct v4l2_subdev *sd, struct v4l2_streamparm *a)
>> +{
>> + struct v4l2_subdev_frame_interval ival = { 0 };
>> + int ret;
>> +
>> + if (a->type != V4L2_BUF_TYPE_VIDEO_CAPTURE &&
>> + a->type != V4L2_BUF_TYPE_VIDEO_CAPTURE_MPLANE)
>> + return -EINVAL;
>> +
>> + if (vdev->device_caps & V4L2_CAP_READWRITE)
>> + a->parm.capture.readbuffers = 2;
>
> Hmm... why don't you also initialize readbuffers otherwise?
It's specifically for read(). If read() is not supported, then this
is meaningless and should just stay 0. v4l2-compliance checks for this.
The 'readbuffers' field is completely outdated and once this is in
the next step is to see if we can come up with something better. I hate
G/S_PARM.
Regards,
Hans
>
>> + if (v4l2_subdev_has_op(sd, video, g_frame_interval))
>> + a->parm.capture.capability = V4L2_CAP_TIMEPERFRAME;
>> + ret = v4l2_subdev_call(sd, video, g_frame_interval, &ival);
>> + if (!ret)
>> + a->parm.capture.timeperframe = ival.interval;
>> + return ret;
>> +}
>> +EXPORT_SYMBOL_GPL(v4l2_g_parm_cap);
>> +
>> +int v4l2_s_parm_cap(struct video_device *vdev,
>> + struct v4l2_subdev *sd, struct v4l2_streamparm *a)
>> +{
>> + struct v4l2_subdev_frame_interval ival = {
>> + .interval = a->parm.capture.timeperframe
>> + };
>> + int ret;
>> +
>> + if (a->type != V4L2_BUF_TYPE_VIDEO_CAPTURE &&
>> + a->type != V4L2_BUF_TYPE_VIDEO_CAPTURE_MPLANE)
>> + return -EINVAL;
>> +
>> + memset(&a->parm, 0, sizeof(a->parm));
>> + if (vdev->device_caps & V4L2_CAP_READWRITE)
>> + a->parm.capture.readbuffers = 2;
>> + else
>> + a->parm.capture.readbuffers = 0;
>> +
>> + if (v4l2_subdev_has_op(sd, video, g_frame_interval))
>> + a->parm.capture.capability = V4L2_CAP_TIMEPERFRAME;
>> + ret = v4l2_subdev_call(sd, video, s_frame_interval, &ival);
>> + if (!ret)
>> + a->parm.capture.timeperframe = ival.interval;
>> + return ret;
>> +}
>> +EXPORT_SYMBOL_GPL(v4l2_s_parm_cap);
>> diff --git a/include/media/v4l2-common.h b/include/media/v4l2-common.h
>> index e0d95a7c5d48..f3aa1d728c0b 100644
>> --- a/include/media/v4l2-common.h
>> +++ b/include/media/v4l2-common.h
>> @@ -341,4 +341,30 @@ v4l2_find_nearest_format(const struct
>> v4l2_frmsize_discrete *sizes,
>> */
>> void v4l2_get_timestamp(struct timeval *tv);
>>
>> +/**
>> + * v4l2_g_parm_cap - helper routine for vidioc_g_parm to fill this in by
>> + * calling the g_frame_interval op of the given subdev. It only works
>> + * for V4L2_BUF_TYPE_VIDEO_CAPTURE(_MPLANE), hence the _cap in the
>> + * function name.
>> + *
>> + * @vdev: the struct video_device pointer. Used to determine the device
>> caps.
>> + * @sd: the sub-device pointer.
>> + * @a: the VIDIOC_G_PARM argument.
>> + */
>> +int v4l2_g_parm_cap(struct video_device *vdev,
>> + struct v4l2_subdev *sd, struct v4l2_streamparm *a);
>> +
>> +/**
>> + * v4l2_s_parm_cap - helper routine for vidioc_s_parm to fill this in by
>> + * calling the s_frame_interval op of the given subdev. It only works
>> + * for V4L2_BUF_TYPE_VIDEO_CAPTURE(_MPLANE), hence the _cap in the
>> + * function name.
>> + *
>> + * @vdev: the struct video_device pointer. Used to determine the device
>> caps.
>> + * @sd: the sub-device pointer.
>> + * @a: the VIDIOC_S_PARM argument.
>> + */
>> +int v4l2_s_parm_cap(struct video_device *vdev,
>> + struct v4l2_subdev *sd, struct v4l2_streamparm *a);
>> +
>> #endif /* V4L2_COMMON_H_ */
>
>
>
> Thanks,
> Mauro
>
