On 08/04/2017 02:00 PM, Hans Verkuil wrote:
> On 28/07/17 12:05, Hugues Fruchet wrote:
>> Ensure that we start with default pixel format and resolution
>> when opening a new instance.
>
> Why? The format is persistent in V4L2 and (re)opening the video device
> shouldn't change the format.
>
> Suppose you use v4l2-ctl to set up a format. E.g. v4l2-ctl -v
> width=320,height-240.
> Now run v4l2-ctl -V to get the format and with this code it would suddenly be
> back to the default!
>
> You set up the default format in the dcmi_graph_notify_complete, but after
> that
> it is only changed if userspace explicitly requests it.
>
> Regards,
>
> Hans
>
Thanks Hans, I didn't catch this before, thanks for explanation.
>>
>> Signed-off-by: Hugues Fruchet <hugues.fruc...@st.com>
>> ---
>> drivers/media/platform/stm32/stm32-dcmi.c | 49
>> ++++++++++++++++++-------------
>> 1 file changed, 28 insertions(+), 21 deletions(-)
>>
>> diff --git a/drivers/media/platform/stm32/stm32-dcmi.c
>> b/drivers/media/platform/stm32/stm32-dcmi.c
>> index 4733d1f..2be56b6 100644
>> --- a/drivers/media/platform/stm32/stm32-dcmi.c
>> +++ b/drivers/media/platform/stm32/stm32-dcmi.c
>> @@ -890,6 +890,28 @@ static int dcmi_enum_frameintervals(struct file *file,
>> void *fh,
>> return 0;
>> }
>>
>> +static int dcmi_set_default_fmt(struct stm32_dcmi *dcmi)
>> +{
>> + struct v4l2_format f = {
>> + .type = V4L2_BUF_TYPE_VIDEO_CAPTURE,
>> + .fmt.pix = {
>> + .width = CIF_WIDTH,
>> + .height = CIF_HEIGHT,
>> + .field = V4L2_FIELD_NONE,
>> + .pixelformat = dcmi->sd_formats[0]->fourcc,
>> + },
>> + };
>> + int ret;
>> +
>> + ret = dcmi_try_fmt(dcmi, &f, NULL);
>> + if (ret)
>> + return ret;
>> + dcmi->sd_format = dcmi->sd_formats[0];
>> + dcmi->fmt = f;
>> +
>> + return 0;
>> +}
>> +
>> static const struct of_device_id stm32_dcmi_of_match[] = {
>> { .compatible = "st,stm32-dcmi"},
>> { /* end node */ },
>> @@ -916,7 +938,13 @@ static int dcmi_open(struct file *file)
>> if (ret < 0 && ret != -ENOIOCTLCMD)
>> goto fh_rel;
>>
>> + ret = dcmi_set_default_fmt(dcmi);
>> + if (ret)
>> + goto power_off;
>> +
>> ret = dcmi_set_fmt(dcmi, &dcmi->fmt);
>> +
>> +power_off:
>> if (ret)
>> v4l2_subdev_call(sd, core, s_power, 0);
>> fh_rel:
>> @@ -991,27 +1019,6 @@ static int dcmi_release(struct file *file)
>> .read = vb2_fop_read,
>> };
>>
>> -static int dcmi_set_default_fmt(struct stm32_dcmi *dcmi)
>> -{
>> - struct v4l2_format f = {
>> - .type = V4L2_BUF_TYPE_VIDEO_CAPTURE,
>> - .fmt.pix = {
>> - .width = CIF_WIDTH,
>> - .height = CIF_HEIGHT,
>> - .field = V4L2_FIELD_NONE,
>> - .pixelformat = dcmi->sd_formats[0]->fourcc,
>> - },
>> - };
>> - int ret;
>> -
>> - ret = dcmi_try_fmt(dcmi, &f, NULL);
>> - if (ret)
>> - return ret;
>> - dcmi->sd_format = dcmi->sd_formats[0];
>> - dcmi->fmt = f;
>> - return 0;
>> -}
>> -
>> static const struct dcmi_format dcmi_formats[] = {
>> {
>> .fourcc = V4L2_PIX_FMT_RGB565,
>>
>
