Re: [PATCH v2 3/3] media: vimc: deb: Add support for {RGB,BGR,GBR}888 bus formats on source pad

[NÃcolas F. R. A. Prado]

Hi Helen,

thanks for the review.

Some comments below.

On Mon, Mar 30, 2020 at 04:43:53PM -0300, Helen Koike wrote:
> 
> Hello,
> 
> On 3/26/20 7:06 PM, Shuah Khan wrote:
> > On 3/26/20 3:47 PM, NÃcolas F. R. A. Prado wrote:
> >> Add support for RGB888_*, BGR888_* and GBR888_* media bus formats on
> >> the source pad of debayer subdevices.
> >>
> >> Co-developed-by: Vitor Massaru Iha <vitor@xxxxxxxxxxx>
> >> Signed-off-by: Vitor Massaru Iha <vitor@xxxxxxxxxxx>
> >> Signed-off-by: NÃcolas F. R. A. Prado <nfraprado@xxxxxxxxxxxxxx>
> >> ---
> >>
> >> Changes in v2:
> >> - Change commit message to reflect v2 changes
> >> - Rename variables
> >> - Fix array formatting
> >> - Add vimc_deb_is_src_code_valid function
> >> - Add other BGR888 and RGB888 formats to debayer source pad supported
> >> ÂÂ formats
> >>
> >> Â drivers/media/platform/vimc/vimc-debayer.c | 61 +++++++++++++++++-----
> >> Â 1 file changed, 49 insertions(+), 12 deletions(-)
> >>
> >> diff --git a/drivers/media/platform/vimc/vimc-debayer.c b/drivers/media/platform/vimc/vimc-debayer.c
> >> index baf6bf9f65b5..33a9bea770bc 100644
> >> --- a/drivers/media/platform/vimc/vimc-debayer.c
> >> +++ b/drivers/media/platform/vimc/vimc-debayer.c
> >> @@ -51,6 +51,19 @@ static const struct v4l2_mbus_framefmt sink_fmt_default = {
> >> ÂÂÂÂÂ .colorspace = V4L2_COLORSPACE_DEFAULT,
> >> Â };
> >> Â +static const u32 vimc_deb_src_mbus_codes[] = {
> >> +ÂÂÂ MEDIA_BUS_FMT_GBR888_1X24,
> >> +ÂÂÂ MEDIA_BUS_FMT_BGR888_1X24,
> >> +ÂÂÂ MEDIA_BUS_FMT_BGR888_3X8,
> >> +ÂÂÂ MEDIA_BUS_FMT_RGB888_1X24,
> >> +ÂÂÂ MEDIA_BUS_FMT_RGB888_2X12_BE,
> >> +ÂÂÂ MEDIA_BUS_FMT_RGB888_2X12_LE,
> >> +ÂÂÂ MEDIA_BUS_FMT_RGB888_3X8,
> >> +ÂÂÂ MEDIA_BUS_FMT_RGB888_1X7X4_SPWG,
> >> +ÂÂÂ MEDIA_BUS_FMT_RGB888_1X7X4_JEIDA,
> >> +ÂÂÂ MEDIA_BUS_FMT_RGB888_1X32_PADHI,
> >> +};
> >> +
> >> Â static const struct vimc_deb_pix_map vimc_deb_pix_map_list[] = {
> >> ÂÂÂÂÂ {
> >> ÂÂÂÂÂÂÂÂÂ .code = MEDIA_BUS_FMT_SBGGR8_1X8,
> >> @@ -125,6 +138,17 @@ static const struct vimc_deb_pix_map *vimc_deb_pix_map_by_code(u32 code)
> >> ÂÂÂÂÂ return NULL;
> >> Â }
> >> Â +static int vimc_deb_is_src_code_invalid(u32 code)
> >> +{
> >> +ÂÂÂ unsigned int i;
> >> +
> >> +ÂÂÂ for (i = 0; i < ARRAY_SIZE(vimc_deb_src_mbus_codes); i++)
> >> +ÂÂÂÂÂÂÂ if (vimc_deb_src_mbus_codes[i] == code)
> >> +ÂÂÂÂÂÂÂÂÂÂÂ return 0;
> >> +
> >> +ÂÂÂ return -EINVAL;
> >> +}
> 
> The naming is a bit confusing, since it checks if it is invalid, but returns a negative number if so.
> 
> How about renaming to vimc_deb_src_code_is_valid ?

I also don't like that the function is called 'is_invalid', but I gave it that
name because I think it actually is less confusing when calling.
For example, later in this patch I do:

ÂÂÂ } else if (vimc_deb_is_src_code_invalid(fse->code)) {
        return -EINVAL;

Which to me becomes very clear.

Since the error values evaluate to True, the other alternative that I
see is to call it 'is_valid', but return 0 when invalid and 1 when valid.
But then we no longer return the -EINVAL value, which I think makes the function
less clear.

What do you think?

Thank you,
NÃcolas

> 
> >> +
> >> Â static int vimc_deb_init_cfg(struct v4l2_subdev *sd,
> >> ÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂ struct v4l2_subdev_pad_config *cfg)
> >> Â {
> >> @@ -148,14 +172,11 @@ static int vimc_deb_enum_mbus_code(struct v4l2_subdev *sd,
> >> ÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂ struct v4l2_subdev_pad_config *cfg,
> >> ÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂ struct v4l2_subdev_mbus_code_enum *code)
> >> Â {
> >> -ÂÂÂ /* We only support one format for source pads */
> >> ÂÂÂÂÂ if (VIMC_IS_SRC(code->pad)) {
> >> -ÂÂÂÂÂÂÂ struct vimc_deb_device *vdeb = v4l2_get_subdevdata(sd);
> >> -
> >> -ÂÂÂÂÂÂÂ if (code->index)
> >> +ÂÂÂÂÂÂÂ if (code->index >= ARRAY_SIZE(vimc_deb_src_mbus_codes))
> >> ÂÂÂÂÂÂÂÂÂÂÂÂÂ return -EINVAL;
> >> Â -ÂÂÂÂÂÂÂ code->code = vdeb->src_code;
> >> +ÂÂÂÂÂÂÂ code->code = vimc_deb_src_mbus_codes[code->index];
> >> ÂÂÂÂÂ } else {
> >> ÂÂÂÂÂÂÂÂÂ if (code->index >= ARRAY_SIZE(vimc_deb_pix_map_list))
> >> ÂÂÂÂÂÂÂÂÂÂÂÂÂ return -EINVAL;
> >> @@ -170,8 +191,6 @@ static int vimc_deb_enum_frame_size(struct v4l2_subdev *sd,
> >> ÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂ struct v4l2_subdev_pad_config *cfg,
> >> ÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂ struct v4l2_subdev_frame_size_enum *fse)
> >> Â {
> >> -ÂÂÂ struct vimc_deb_device *vdeb = v4l2_get_subdevdata(sd);
> >> -
> >> ÂÂÂÂÂ if (fse->index)
> >> ÂÂÂÂÂÂÂÂÂ return -EINVAL;
> >> Â @@ -181,7 +200,7 @@ static int vimc_deb_enum_frame_size(struct v4l2_subdev *sd,
> >> Â ÂÂÂÂÂÂÂÂÂ if (!vpix)
> >> ÂÂÂÂÂÂÂÂÂÂÂÂÂ return -EINVAL;
> >> -ÂÂÂ } else if (fse->code != vdeb->src_code) {
> >> +ÂÂÂ } else if (vimc_deb_is_src_code_invalid(fse->code)) {
> >> ÂÂÂÂÂÂÂÂÂ return -EINVAL;
> >> ÂÂÂÂÂ }
> >> Â @@ -237,6 +256,7 @@ static int vimc_deb_set_fmt(struct v4l2_subdev *sd,
> >> Â {
> >> ÂÂÂÂÂ struct vimc_deb_device *vdeb = v4l2_get_subdevdata(sd);
> >> ÂÂÂÂÂ struct v4l2_mbus_framefmt *sink_fmt;
> >> +ÂÂÂ u32 *src_code;
> >> Â ÂÂÂÂÂ if (fmt->which == V4L2_SUBDEV_FORMAT_ACTIVE) {
> >> ÂÂÂÂÂÂÂÂÂ /* Do not change the format while stream is on */
> >> @@ -244,8 +264,10 @@ static int vimc_deb_set_fmt(struct v4l2_subdev *sd,
> >> ÂÂÂÂÂÂÂÂÂÂÂÂÂ return -EBUSY;
> >> Â ÂÂÂÂÂÂÂÂÂ sink_fmt = &vdeb->sink_fmt;
> >> +ÂÂÂÂÂÂÂ src_code = &vdeb->src_code;
> >> ÂÂÂÂÂ } else {
> >> ÂÂÂÂÂÂÂÂÂ sink_fmt = v4l2_subdev_get_try_format(sd, cfg, 0);
> >> +ÂÂÂÂÂÂÂ src_code = &v4l2_subdev_get_try_format(sd, cfg, 1)->code;
> >> ÂÂÂÂÂ }
> >> Â ÂÂÂÂÂ /*
> >> @@ -253,9 +275,14 @@ static int vimc_deb_set_fmt(struct v4l2_subdev *sd,
> >> ÂÂÂÂÂÂ * it is propagated from the sink
> >> ÂÂÂÂÂÂ */
> >> ÂÂÂÂÂ if (VIMC_IS_SRC(fmt->pad)) {
> >> +ÂÂÂÂÂÂÂ u32 code = fmt->format.code;
> >> +
> >> ÂÂÂÂÂÂÂÂÂ fmt->format = *sink_fmt;
> >> -ÂÂÂÂÂÂÂ /* TODO: Add support for other formats */
> >> -ÂÂÂÂÂÂÂ fmt->format.code = vdeb->src_code;
> >> +
> >> +ÂÂÂÂÂÂÂ if (!vimc_deb_is_src_code_invalid(code))
> >> +ÂÂÂÂÂÂÂÂÂÂÂ *src_code = code;
> >> +
> >> +ÂÂÂÂÂÂÂ fmt->format.code = *src_code;
> >> ÂÂÂÂÂ } else {
> >> ÂÂÂÂÂÂÂÂÂ /* Set the new format in the sink pad */
> >> ÂÂÂÂÂÂÂÂÂ vimc_deb_adjust_sink_fmt(&fmt->format);
> >> @@ -291,11 +318,21 @@ static void vimc_deb_set_rgb_mbus_fmt_rgb888_1x24(struct vimc_deb_device *vdeb,
> >> ÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂ unsigned int col,
> >> ÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂ unsigned int rgb[3])
> >
> > Change this to pass a pointer and size.
> 
> Hi Shuah,
> 
> Modifying vimc_deb_set_rgb_mbus_fmt_rgb888_1x24() is not part of this patch, or do you mean another part of the code?
> 
> Thanks for reviewing
> Helen
> 
> >
> >> Â {
> >> +ÂÂÂ const struct vimc_pix_map *vpix;
> >> ÂÂÂÂÂ unsigned int i, index;
> >> Â +ÂÂÂ vpix = vimc_pix_map_by_code(vdeb->src_code);
> >> ÂÂÂÂÂ index = VIMC_FRAME_INDEX(lin, col, vdeb->sink_fmt.width, 3);
> >> -ÂÂÂ for (i = 0; i < 3; i++)
> >> -ÂÂÂÂÂÂÂ vdeb->src_frame[index + i] = rgb[i];
> >> +ÂÂÂ for (i = 0; i < 3; i++) {
> >> +ÂÂÂÂÂÂÂ switch (vpix->pixelformat) {
> >> +ÂÂÂÂÂÂÂ case V4L2_PIX_FMT_RGB24:
> >> +ÂÂÂÂÂÂÂÂÂÂÂ vdeb->src_frame[index + i] = rgb[i];
> >> +ÂÂÂÂÂÂÂÂÂÂÂ break;
> >> +ÂÂÂÂÂÂÂ case V4L2_PIX_FMT_BGR24:
> >> +ÂÂÂÂÂÂÂÂÂÂÂ vdeb->src_frame[index + i] = rgb[2-i];
> >> +ÂÂÂÂÂÂÂÂÂÂÂ break;
> >> +ÂÂÂÂÂÂÂ }
> >> +ÂÂÂ }
> >> Â }
> >> Â Â static int vimc_deb_s_stream(struct v4l2_subdev *sd, int enable)
> >>
> >
> > thanks,
> > -- Shuah