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

[Helen Koike <helen.koike@collabora.com>]

On 11/10/19 4:35 PM, Guilherme Alcarde Gallo wrote:
> 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.

It is used if you compile with make W=1

For reference: https://lists.linuxfoundation.org/pipermail/ksummit-discuss/2019-September/006969.html

Regards,
Helen

> 
> 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@xs4all.nl> 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@gmail.com>
>>> Co-developed-by: Danilo Figueiredo Rocha <drocha.figueiredo@gmail.com>
>>> Signed-off-by: Danilo Figueiredo Rocha <drocha.figueiredo@gmail.com>
>>> Acked-by: Helen Koike <helen.koike@collabora.com>
>>>
>>> ---
>>> 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 ‘vimc_sca_set_selection’:
>> drivers/media/platform/vimc/vimc-scaler.c:290:19: warning: variable ‘sink_rect’ 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;
>>>  }
>>>
>>