Re: [PATCH v4] media: vimc: Implement get/set selection in sink

[Guilherme Alcarde Gallo]

Hi Hans,

Thanks for testing the compilation.

I didn't know that -Wunused-but-set-variable flag was not being
employed in the default kernel compilation.

I just sent a v5 fixing this warning.
This variable was unnecessary since vimc_sca_adjust_sink_crop function
already creates an internal v4l2_rect to be adjusted to the crop
region.

On Sat, Nov 9, 2019 at 8:50 AM Hans Verkuil <hverkuil-cisco@xxxxxxxxx> wrote:
>
> On 11/8/19 3:45 AM, Guilherme Alcarde Gallo wrote:
> > Add support for the sink pad of scaler subdevice to respond
> > VIDIOC_G_SELECTION and VIDIOC_S_SELECTION ioctls with the following
> > targets: V4L2_SEL_TGT_COMPOSE_BOUNDS and V4L2_SEL_TGT_CROP.
> >
> > * Add new const struct crop_rect_default to initialize subdev scaler
> >   properly.
> > * Make changes in sink pad format reflect to the crop rectangle. E.g.
> >   changing the frame format to a smaller size one can make the former
> >   crop rectangle selects a non existing frame area. To solve this
> >   situation the crop rectangle is clamped to the frame boundaries.
> > * Clamp crop rectangle respecting the sink bounds during set_selection
> >   ioctl.
> >
> > Signed-off-by: Guilherme Alcarde Gallo <gagallo7@xxxxxxxxx>
> > Co-developed-by: Danilo Figueiredo Rocha <drocha.figueiredo@xxxxxxxxx>
> > Signed-off-by: Danilo Figueiredo Rocha <drocha.figueiredo@xxxxxxxxx>
> > Acked-by: Helen Koike <helen.koike@xxxxxxxxxxxxx>
> >
> > ---
> > Changes in V4:
> > * Revert an unnecessary change in headers include order.
> > * Sort the declaration order for local variables in function by the size
> >   descending.
> >
> > Changes in V3:
> > * Sort the headers in alphabetical order.
> > * Change all functions prefix to 'vimc_sca_'.
> > * Remove useless case.
> > * Change commit message subject.
> >
> > Changes in V2:
> > * Use v4l2_rect_map_inside to clamp the crop rectangle.
> > * Do the crop rectangle clamping after changing sink format.
> > * Implement try ioctls for selection with CROP* targets.
> > * Treat tiny rectangles with area smaller than minimal dimensions of
> >   vimc frames.
> > * Allow user to get selection when the streaming is on.
> > * Reuse bound rectangle generation in a static function.
> > * Disable get_selection for Source pads as we did before with
> >   set_selection.
> > ---
> > ---
> >  drivers/media/platform/vimc/vimc-scaler.c | 168 ++++++++++++++++++++--
> >  1 file changed, 153 insertions(+), 15 deletions(-)
> >
> > diff --git a/drivers/media/platform/vimc/vimc-scaler.c b/drivers/media/platform/vimc/vimc-scaler.c
> > index 2f88a7d9d67b..36425cffc0ad 100644
> > --- a/drivers/media/platform/vimc/vimc-scaler.c
> > +++ b/drivers/media/platform/vimc/vimc-scaler.c
> > @@ -8,6 +8,7 @@
> >  #include <linux/moduleparam.h>
> >  #include <linux/vmalloc.h>
> >  #include <linux/v4l2-mediabus.h>
> > +#include <media/v4l2-rect.h>
> >  #include <media/v4l2-subdev.h>
> >
> >  #include "vimc-common.h"
> > @@ -18,6 +19,9 @@ MODULE_PARM_DESC(sca_mult, " the image size multiplier");
> >
> >  #define MAX_ZOOM     8
> >
> > +#define VIMC_SCA_FMT_WIDTH_DEFAULT  640
> > +#define VIMC_SCA_FMT_HEIGHT_DEFAULT 480
> > +
> >  struct vimc_sca_device {
> >       struct vimc_ent_device ved;
> >       struct v4l2_subdev sd;
> > @@ -25,6 +29,7 @@ struct vimc_sca_device {
> >        * with the width and hight multiplied by mult
> >        */
> >       struct v4l2_mbus_framefmt sink_fmt;
> > +     struct v4l2_rect crop_rect;
> >       /* Values calculated when the stream starts */
> >       u8 *src_frame;
> >       unsigned int src_line_size;
> > @@ -33,22 +38,64 @@ struct vimc_sca_device {
> >  };
> >
> >  static const struct v4l2_mbus_framefmt sink_fmt_default = {
> > -     .width = 640,
> > -     .height = 480,
> > +     .width = VIMC_SCA_FMT_WIDTH_DEFAULT,
> > +     .height = VIMC_SCA_FMT_HEIGHT_DEFAULT,
> >       .code = MEDIA_BUS_FMT_RGB888_1X24,
> >       .field = V4L2_FIELD_NONE,
> >       .colorspace = V4L2_COLORSPACE_DEFAULT,
> >  };
> >
> > +static const struct v4l2_rect crop_rect_default = {
> > +     .width = VIMC_SCA_FMT_WIDTH_DEFAULT,
> > +     .height = VIMC_SCA_FMT_HEIGHT_DEFAULT,
> > +     .top = 0,
> > +     .left = 0,
> > +};
> > +
> > +static const struct v4l2_rect crop_rect_min = {
> > +     .width = VIMC_FRAME_MIN_WIDTH,
> > +     .height = VIMC_FRAME_MIN_HEIGHT,
> > +     .top = 0,
> > +     .left = 0,
> > +};
> > +
> > +static struct v4l2_rect
> > +vimc_sca_get_crop_bound_sink(const struct v4l2_mbus_framefmt *sink_fmt)
> > +{
> > +     /* Get the crop bounds to clamp the crop rectangle correctly */
> > +     struct v4l2_rect r = {
> > +             .left = 0,
> > +             .top = 0,
> > +             .width = sink_fmt->width,
> > +             .height = sink_fmt->height,
> > +     };
> > +     return r;
> > +}
> > +
> > +static void vimc_sca_adjust_sink_crop(struct v4l2_rect *r,
> > +                                   const struct v4l2_mbus_framefmt *sink_fmt)
> > +{
> > +     const struct v4l2_rect sink_rect =
> > +             vimc_sca_get_crop_bound_sink(sink_fmt);
> > +
> > +     /* Disallow rectangles smaller than the minimal one. */
> > +     v4l2_rect_set_min_size(r, &crop_rect_min);
> > +     v4l2_rect_map_inside(r, &sink_rect);
> > +}
> > +
> >  static int vimc_sca_init_cfg(struct v4l2_subdev *sd,
> >                            struct v4l2_subdev_pad_config *cfg)
> >  {
> >       struct v4l2_mbus_framefmt *mf;
> > +     struct v4l2_rect *r;
> >       unsigned int i;
> >
> >       mf = v4l2_subdev_get_try_format(sd, cfg, 0);
> >       *mf = sink_fmt_default;
> >
> > +     r = v4l2_subdev_get_try_crop(sd, cfg, 0);
> > +     *r = crop_rect_default;
> > +
> >       for (i = 1; i < sd->entity.num_pads; i++) {
> >               mf = v4l2_subdev_get_try_format(sd, cfg, i);
> >               *mf = sink_fmt_default;
> > @@ -107,16 +154,21 @@ static int vimc_sca_get_fmt(struct v4l2_subdev *sd,
> >                           struct v4l2_subdev_format *format)
> >  {
> >       struct vimc_sca_device *vsca = v4l2_get_subdevdata(sd);
> > +     struct v4l2_rect *crop_rect;
> >
> >       /* Get the current sink format */
> > -     format->format = (format->which == V4L2_SUBDEV_FORMAT_TRY) ?
> > -                      *v4l2_subdev_get_try_format(sd, cfg, 0) :
> > -                      vsca->sink_fmt;
> > +     if (format->which == V4L2_SUBDEV_FORMAT_TRY) {
> > +             format->format = *v4l2_subdev_get_try_format(sd, cfg, 0);
> > +             crop_rect = v4l2_subdev_get_try_crop(sd, cfg, 0);
> > +     } else {
> > +             format->format = vsca->sink_fmt;
> > +             crop_rect = &vsca->crop_rect;
> > +     }
> >
> >       /* Scale the frame size for the source pad */
> >       if (VIMC_IS_SRC(format->pad)) {
> > -             format->format.width = vsca->sink_fmt.width * sca_mult;
> > -             format->format.height = vsca->sink_fmt.height * sca_mult;
> > +             format->format.width = crop_rect->width * sca_mult;
> > +             format->format.height = crop_rect->height * sca_mult;
> >       }
> >
> >       return 0;
> > @@ -148,6 +200,7 @@ static int vimc_sca_set_fmt(struct v4l2_subdev *sd,
> >  {
> >       struct vimc_sca_device *vsca = v4l2_get_subdevdata(sd);
> >       struct v4l2_mbus_framefmt *sink_fmt;
> > +     struct v4l2_rect *crop_rect;
> >
> >       if (fmt->which == V4L2_SUBDEV_FORMAT_ACTIVE) {
> >               /* Do not change the format while stream is on */
> > @@ -155,8 +208,10 @@ static int vimc_sca_set_fmt(struct v4l2_subdev *sd,
> >                       return -EBUSY;
> >
> >               sink_fmt = &vsca->sink_fmt;
> > +             crop_rect = &vsca->crop_rect;
> >       } else {
> >               sink_fmt = v4l2_subdev_get_try_format(sd, cfg, 0);
> > +             crop_rect = v4l2_subdev_get_try_crop(sd, cfg, 0);
> >       }
> >
> >       /*
> > @@ -165,8 +220,8 @@ static int vimc_sca_set_fmt(struct v4l2_subdev *sd,
> >        */
> >       if (VIMC_IS_SRC(fmt->pad)) {
> >               fmt->format = *sink_fmt;
> > -             fmt->format.width = sink_fmt->width * sca_mult;
> > -             fmt->format.height = sink_fmt->height * sca_mult;
> > +             fmt->format.width = crop_rect->width * sca_mult;
> > +             fmt->format.height = crop_rect->height * sca_mult;
> >       } else {
> >               /* Set the new format in the sink pad */
> >               vimc_sca_adjust_sink_fmt(&fmt->format);
> > @@ -184,6 +239,80 @@ static int vimc_sca_set_fmt(struct v4l2_subdev *sd,
> >                       fmt->format.xfer_func, fmt->format.ycbcr_enc);
> >
> >               *sink_fmt = fmt->format;
> > +
> > +             /* Do the crop, but respect the current bounds */
> > +             vimc_sca_adjust_sink_crop(crop_rect, sink_fmt);
> > +     }
> > +
> > +     return 0;
> > +}
> > +
> > +static int vimc_sca_get_selection(struct v4l2_subdev *sd,
> > +                               struct v4l2_subdev_pad_config *cfg,
> > +                               struct v4l2_subdev_selection *sel)
> > +{
> > +     struct vimc_sca_device *vsca = v4l2_get_subdevdata(sd);
> > +     struct v4l2_mbus_framefmt *sink_fmt;
> > +     struct v4l2_rect *crop_rect;
> > +
> > +     if (VIMC_IS_SRC(sel->pad))
> > +             return -EINVAL;
> > +
> > +     if (sel->which == V4L2_SUBDEV_FORMAT_ACTIVE) {
> > +             sink_fmt = &vsca->sink_fmt;
> > +             crop_rect = &vsca->crop_rect;
> > +     } else {
> > +             sink_fmt = v4l2_subdev_get_try_format(sd, cfg, 0);
> > +             crop_rect = v4l2_subdev_get_try_crop(sd, cfg, 0);
> > +     }
> > +
> > +     switch (sel->target) {
> > +     case V4L2_SEL_TGT_CROP:
> > +             sel->r = *crop_rect;
> > +             break;
> > +     case V4L2_SEL_TGT_CROP_BOUNDS:
> > +             sel->r = vimc_sca_get_crop_bound_sink(sink_fmt);
> > +             break;
> > +     default:
> > +             return -EINVAL;
> > +     }
> > +
> > +     return 0;
> > +}
> > +
> > +static int vimc_sca_set_selection(struct v4l2_subdev *sd,
> > +                               struct v4l2_subdev_pad_config *cfg,
> > +                               struct v4l2_subdev_selection *sel)
> > +{
> > +     struct vimc_sca_device *vsca = v4l2_get_subdevdata(sd);
> > +     struct v4l2_mbus_framefmt *sink_fmt;
> > +     struct v4l2_rect *crop_rect;
> > +     struct v4l2_rect sink_rect;
> > +
> > +     if (VIMC_IS_SRC(sel->pad))
> > +             return -EINVAL;
> > +
> > +     if (sel->which == V4L2_SUBDEV_FORMAT_ACTIVE) {
> > +             /* Do not change the format while stream is on */
> > +             if (vsca->src_frame)
> > +                     return -EBUSY;
> > +
> > +             crop_rect = &vsca->crop_rect;
> > +             sink_fmt = &vsca->sink_fmt;
> > +     } else {
> > +             crop_rect = v4l2_subdev_get_try_crop(sd, cfg, 0);
> > +             sink_fmt = v4l2_subdev_get_try_format(sd, cfg, 0);
> > +     }
> > +
> > +     switch (sel->target) {
> > +     case V4L2_SEL_TGT_CROP:
> > +             /* Do the crop, but respect the current bounds */
> > +             sink_rect = vimc_sca_get_crop_bound_sink(sink_fmt);
> > +             vimc_sca_adjust_sink_crop(&sel->r, sink_fmt);
> > +             *crop_rect = sel->r;
>
> drivers/media/platform/vimc/vimc-scaler.c: In function âvimc_sca_set_selectionâ:
> drivers/media/platform/vimc/vimc-scaler.c:290:19: warning: variable âsink_rectâ set but not used [-Wunused-but-set-variable]
>   290 |  struct v4l2_rect sink_rect;
>       |                   ^~~~~~~~~
>
> Something is wrong here.
>
> Regards,
>
>         Hans
>
> > +             break;
> > +     default:
> > +             return -EINVAL;
> >       }
> >
> >       return 0;
> > @@ -195,6 +324,8 @@ static const struct v4l2_subdev_pad_ops vimc_sca_pad_ops = {
> >       .enum_frame_size        = vimc_sca_enum_frame_size,
> >       .get_fmt                = vimc_sca_get_fmt,
> >       .set_fmt                = vimc_sca_set_fmt,
> > +     .get_selection          = vimc_sca_get_selection,
> > +     .set_selection          = vimc_sca_set_selection,
> >  };
> >
> >  static int vimc_sca_s_stream(struct v4l2_subdev *sd, int enable)
> > @@ -213,11 +344,11 @@ static int vimc_sca_s_stream(struct v4l2_subdev *sd, int enable)
> >               vsca->bpp = vpix->bpp;
> >
> >               /* Calculate the width in bytes of the src frame */
> > -             vsca->src_line_size = vsca->sink_fmt.width *
> > +             vsca->src_line_size = vsca->crop_rect.width *
> >                                     sca_mult * vsca->bpp;
> >
> >               /* Calculate the frame size of the source pad */
> > -             frame_size = vsca->src_line_size * vsca->sink_fmt.height *
> > +             frame_size = vsca->src_line_size * vsca->crop_rect.height *
> >                            sca_mult;
> >
> >               /* Allocate the frame buffer. Use vmalloc to be able to
> > @@ -259,9 +390,10 @@ static void vimc_sca_fill_pix(u8 *const ptr,
> >  }
> >
> >  static void vimc_sca_scale_pix(const struct vimc_sca_device *const vsca,
> > -                            const unsigned int lin, const unsigned int col,
> > +                            unsigned int lin, unsigned int col,
> >                              const u8 *const sink_frame)
> >  {
> > +     const struct v4l2_rect crop_rect = vsca->crop_rect;
> >       unsigned int i, j, index;
> >       const u8 *pixel;
> >
> > @@ -278,8 +410,10 @@ static void vimc_sca_scale_pix(const struct vimc_sca_device *const vsca,
> >       /* point to the place we are going to put the first pixel
> >        * in the scaled src frame
> >        */
> > +     lin -= crop_rect.top;
> > +     col -= crop_rect.left;
> >       index = VIMC_FRAME_INDEX(lin * sca_mult, col * sca_mult,
> > -                              vsca->sink_fmt.width * sca_mult, vsca->bpp);
> > +                              crop_rect.width * sca_mult, vsca->bpp);
> >
> >       dev_dbg(vsca->ved.dev, "sca: %s: scale_pix src pos %dx%d, index %d\n",
> >               vsca->sd.name, lin * sca_mult, col * sca_mult, index);
> > @@ -307,12 +441,13 @@ static void vimc_sca_scale_pix(const struct vimc_sca_device *const vsca,
> >  static void vimc_sca_fill_src_frame(const struct vimc_sca_device *const vsca,
> >                                   const u8 *const sink_frame)
> >  {
> > +     const struct v4l2_rect r = vsca->crop_rect;
> >       unsigned int i, j;
> >
> >       /* Scale each pixel from the original sink frame */
> >       /* TODO: implement scale down, only scale up is supported for now */
> > -     for (i = 0; i < vsca->sink_fmt.height; i++)
> > -             for (j = 0; j < vsca->sink_fmt.width; j++)
> > +     for (i = r.top; i < r.top + r.height; i++)
> > +             for (j = r.left; j < r.left + r.width; j++)
> >                       vimc_sca_scale_pix(vsca, i, j, sink_frame);
> >  }
> >
> > @@ -384,5 +519,8 @@ struct vimc_ent_device *vimc_sca_add(struct vimc_device *vimc,
> >       /* Initialize the frame format */
> >       vsca->sink_fmt = sink_fmt_default;
> >
> > +     /* Initialize the crop selection */
> > +     vsca->crop_rect = crop_rect_default;
> > +
> >       return &vsca->ved;
> >  }
> >
>