Re: [PATCH v1 5/5] [media] stm32-dcmi: g_/s_selection crop support
From: Hans Verkuil
Date: Fri Aug 04 2017 - 08:27:00 EST
On 28/07/17 12:05, Hugues Fruchet wrote:
> Implements g_/s_selection crop support by using DCMI crop
> hardware feature.
> User can first get the maximum supported resolution of the sensor
> by calling g_selection(V4L2_SEL_TGT_CROP_BOUNDS).
> Then user call to s_selection(V4L2_SEL_TGT_CROP) will reset sensor
> to its maximum resolution and crop request is saved for later usage
> in s_fmt().
> Next call to s_fmt() will check if sensor can do frame size request
> with crop request. If sensor supports only discrete frame sizes,
> the frame size which is larger than user request is selected in
> order to be able to match the crop request. Then s_fmt() resolution
> user request is adjusted to match crop request resolution.
>
> Signed-off-by: Hugues Fruchet <hugues.fruchet@xxxxxx>
> ---
> drivers/media/platform/stm32/stm32-dcmi.c | 367 +++++++++++++++++++++++++++++-
> 1 file changed, 363 insertions(+), 4 deletions(-)
>
> diff --git a/drivers/media/platform/stm32/stm32-dcmi.c b/drivers/media/platform/stm32/stm32-dcmi.c
> index 2be56b6..f1fb0b3 100644
> --- a/drivers/media/platform/stm32/stm32-dcmi.c
> +++ b/drivers/media/platform/stm32/stm32-dcmi.c
> @@ -33,6 +33,7 @@
> #include <media/v4l2-fwnode.h>
> #include <media/v4l2-image-sizes.h>
> #include <media/v4l2-ioctl.h>
> +#include <media/v4l2-rect.h>
> #include <media/videobuf2-dma-contig.h>
>
> #define DRV_NAME "stm32-dcmi"
> @@ -107,6 +108,11 @@ struct dcmi_format {
> u8 bpp;
> };
>
> +struct dcmi_framesize {
> + u32 width;
> + u32 height;
> +};
> +
> struct dcmi_buf {
> struct vb2_v4l2_buffer vb;
> bool prepared;
> @@ -131,10 +137,16 @@ struct stm32_dcmi {
> struct v4l2_async_notifier notifier;
> struct dcmi_graph_entity entity;
> struct v4l2_format fmt;
> + struct v4l2_rect crop;
> + bool do_crop;
>
> const struct dcmi_format **sd_formats;
> unsigned int nb_of_sd_formats;
> const struct dcmi_format *sd_format;
> + struct dcmi_framesize *sd_framesizes;
> + unsigned int nb_of_sd_framesizes;
num_of_sd_framesizes is better.
> + struct dcmi_framesize sd_framesize;
> + struct v4l2_rect sd_bounds;
>
> /* Protect this data structure */
> struct mutex lock;
> @@ -325,6 +337,28 @@ static int dcmi_start_capture(struct stm32_dcmi *dcmi)
> return 0;
> }
>
> +static void dcmi_set_crop(struct stm32_dcmi *dcmi)
> +{
> + u32 size, start;
> +
> + /* Crop resolution */
> + size = ((dcmi->crop.height - 1) << 16) |
> + ((dcmi->crop.width << 1) - 1);
> + reg_write(dcmi->regs, DCMI_CWSIZE, size);
> +
> + /* Crop start point */
> + start = ((dcmi->crop.top) << 16) |
> + ((dcmi->crop.left << 1));
> + reg_write(dcmi->regs, DCMI_CWSTRT, start);
> +
> + dev_dbg(dcmi->dev, "Cropping to %ux%u@%u:%u\n",
> + dcmi->crop.width, dcmi->crop.height,
> + dcmi->crop.left, dcmi->crop.top);
> +
> + /* Enable crop */
> + reg_set(dcmi->regs, DCMI_CR, CR_CROP);
> +}
> +
> static irqreturn_t dcmi_irq_thread(int irq, void *arg)
> {
> struct stm32_dcmi *dcmi = arg;
> @@ -540,6 +574,10 @@ static int dcmi_start_streaming(struct vb2_queue *vq, unsigned int count)
>
> reg_write(dcmi->regs, DCMI_CR, val);
>
> + /* Set crop */
> + if (dcmi->do_crop)
> + dcmi_set_crop(dcmi);
> +
> /* Enable dcmi */
> reg_set(dcmi->regs, DCMI_CR, CR_ENABLE);
>
> @@ -697,10 +735,37 @@ static const struct dcmi_format *find_format_by_fourcc(struct stm32_dcmi *dcmi,
> return NULL;
> }
>
> +static void __find_outer_frame_size(struct stm32_dcmi *dcmi,
> + struct v4l2_pix_format *pix,
> + struct dcmi_framesize *framesize)
> +{
> + struct dcmi_framesize *match = NULL;
> + unsigned int i;
> + unsigned int min_err = UINT_MAX;
> +
> + for (i = 0; i < dcmi->nb_of_sd_framesizes; i++) {
> + struct dcmi_framesize *fsize = &dcmi->sd_framesizes[i];
> + int w_err = (fsize->width - pix->width);
> + int h_err = (fsize->height - pix->height);
> + int err = w_err + h_err;
> +
> + if ((w_err >= 0) && (h_err >= 0) && (err < min_err)) {
> + min_err = err;
> + match = fsize;
> + }
> + }
> + if (!match)
> + match = &dcmi->sd_framesizes[0];
> +
> + *framesize = *match;
> +}
> +
> static int dcmi_try_fmt(struct stm32_dcmi *dcmi, struct v4l2_format *f,
> - const struct dcmi_format **sd_format)
> + const struct dcmi_format **sd_format,
> + struct dcmi_framesize *sd_framesize)
> {
> const struct dcmi_format *sd_fmt;
> + struct dcmi_framesize sd_fsize;
> struct v4l2_pix_format *pix = &f->fmt.pix;
> struct v4l2_subdev_pad_config pad_cfg;
> struct v4l2_subdev_format format = {
> @@ -718,6 +783,17 @@ static int dcmi_try_fmt(struct stm32_dcmi *dcmi, struct v4l2_format *f,
> pix->width = clamp(pix->width, MIN_WIDTH, MAX_WIDTH);
> pix->height = clamp(pix->height, MIN_HEIGHT, MAX_HEIGHT);
>
> + if (dcmi->do_crop && dcmi->nb_of_sd_framesizes) {
> + struct dcmi_framesize outer_sd_fsize;
> + /*
> + * If crop is requested and sensor have discrete frame sizes,
> + * select the frame size that is just larger than request
> + */
> + __find_outer_frame_size(dcmi, pix, &outer_sd_fsize);
> + pix->width = outer_sd_fsize.width;
> + pix->height = outer_sd_fsize.height;
> + }
> +
> v4l2_fill_mbus_format(&format.format, pix, sd_fmt->mbus_code);
> ret = v4l2_subdev_call(dcmi->entity.subdev, pad, set_fmt,
> &pad_cfg, &format);
> @@ -727,6 +803,31 @@ static int dcmi_try_fmt(struct stm32_dcmi *dcmi, struct v4l2_format *f,
> /* Update pix regarding to what sensor can do */
> v4l2_fill_pix_format(pix, &format.format);
>
> + /* Save resolution that sensor can actually do */
> + sd_fsize.width = pix->width;
> + sd_fsize.height = pix->height;
> +
> + if (dcmi->do_crop) {
> + struct v4l2_rect c = dcmi->crop;
> + struct v4l2_rect max_rect;
> +
> + /*
> + * Adjust crop by making the intersection between
> + * format resolution request and crop request
> + */
> + max_rect.top = 0;
> + max_rect.left = 0;
> + max_rect.width = pix->width;
> + max_rect.height = pix->height;
> + v4l2_rect_map_inside(&c, &max_rect);
> + c.top = clamp_t(s32, c.top, 0, pix->height - c.height);
> + c.left = clamp_t(s32, c.left, 0, pix->width - c.width);
> + dcmi->crop = c;
> +
> + /* Adjust format resolution request to crop */
> + pix->width = dcmi->crop.width;
> + pix->height = dcmi->crop.height;
> + }
>
> pix->field = V4L2_FIELD_NONE;
> pix->bytesperline = pix->width * sd_fmt->bpp;
> @@ -734,6 +835,8 @@ static int dcmi_try_fmt(struct stm32_dcmi *dcmi, struct v4l2_format *f,
>
> if (sd_format)
> *sd_format = sd_fmt;
> + if (sd_framesize)
> + *sd_framesize = sd_fsize;
>
> return 0;
> }
> @@ -744,24 +847,41 @@ static int dcmi_set_fmt(struct stm32_dcmi *dcmi, struct v4l2_format *f)
> .which = V4L2_SUBDEV_FORMAT_ACTIVE,
> };
> const struct dcmi_format *sd_format;
> + struct dcmi_framesize sd_framesize;
> struct v4l2_mbus_framefmt *mf = &format.format;
> struct v4l2_pix_format *pix = &f->fmt.pix;
> int ret;
>
> - ret = dcmi_try_fmt(dcmi, f, &sd_format);
> + /*
> + * Try format, fmt.width/height could have been changed
> + * to match sensor capability or crop request
> + * sd_format & sd_framesize will contain what subdev
> + * can do for this request.
> + */
> + ret = dcmi_try_fmt(dcmi, f, &sd_format, &sd_framesize);
> if (ret)
> return ret;
>
> /* pix to mbus format */
> v4l2_fill_mbus_format(mf, pix,
> sd_format->mbus_code);
> + mf->width = sd_framesize.width;
> + mf->height = sd_framesize.height;
> +
> ret = v4l2_subdev_call(dcmi->entity.subdev, pad,
> set_fmt, NULL, &format);
> if (ret < 0)
> return ret;
>
> + dev_dbg(dcmi->dev, "Sensor format set to 0x%x %ux%u\n",
> + mf->code, mf->width, mf->height);
> + dev_dbg(dcmi->dev, "Buffer format set to %4.4s %ux%u\n",
> + (char *)&pix->pixelformat,
> + pix->width, pix->height);
> +
> dcmi->fmt = *f;
> dcmi->sd_format = sd_format;
> + dcmi->sd_framesize = sd_framesize;
>
> return 0;
> }
> @@ -782,7 +902,7 @@ static int dcmi_try_fmt_vid_cap(struct file *file, void *priv,
> {
> struct stm32_dcmi *dcmi = video_drvdata(file);
>
> - return dcmi_try_fmt(dcmi, f, NULL);
> + return dcmi_try_fmt(dcmi, f, NULL, NULL);
> }
>
> static int dcmi_enum_fmt_vid_cap(struct file *file, void *priv,
> @@ -797,6 +917,186 @@ static int dcmi_enum_fmt_vid_cap(struct file *file, void *priv,
> return 0;
> }
>
> +static int dcmi_get_sensor_format(struct stm32_dcmi *dcmi,
> + struct v4l2_pix_format *pix)
> +{
> + struct v4l2_subdev_format fmt = {
> + .which = V4L2_SUBDEV_FORMAT_ACTIVE,
> + };
> + int ret;
> +
> + ret = v4l2_subdev_call(dcmi->entity.subdev, pad, get_fmt, NULL, &fmt);
> + if (ret)
> + return ret;
> +
> + v4l2_fill_pix_format(pix, &fmt.format);
> +
> + return 0;
> +}
> +
> +static int dcmi_set_sensor_format(struct stm32_dcmi *dcmi,
> + struct v4l2_pix_format *pix)
> +{
> + const struct dcmi_format *sd_fmt;
> + struct v4l2_subdev_format format = {
> + .which = V4L2_SUBDEV_FORMAT_TRY,
> + };
> + struct v4l2_subdev_pad_config pad_cfg;
> + int ret;
> +
> + sd_fmt = find_format_by_fourcc(dcmi, pix->pixelformat);
> + if (!sd_fmt) {
> + sd_fmt = dcmi->sd_formats[dcmi->nb_of_sd_formats - 1];
> + pix->pixelformat = sd_fmt->fourcc;
> + }
> +
> + v4l2_fill_mbus_format(&format.format, pix, sd_fmt->mbus_code);
> + ret = v4l2_subdev_call(dcmi->entity.subdev, pad, set_fmt,
> + &pad_cfg, &format);
> + if (ret < 0)
> + return ret;
> +
> + return 0;
> +}
> +
> +static int dcmi_get_sensor_bounds(struct stm32_dcmi *dcmi,
> + struct v4l2_rect *r)
> +{
> + struct v4l2_subdev_selection bounds = {
> + .which = V4L2_SUBDEV_FORMAT_ACTIVE,
> + .target = V4L2_SEL_TGT_CROP_BOUNDS,
> + };
> + unsigned int max_width, max_height, max_pixsize;
> + struct v4l2_pix_format pix;
> + unsigned int i;
> + int ret;
> +
> + /*
> + * Get sensor bounds first
> + */
> + ret = v4l2_subdev_call(dcmi->entity.subdev, pad, get_selection,
> + NULL, &bounds);
> + if (!ret)
> + *r = bounds.r;
> + if (ret != -ENOIOCTLCMD)
> + return ret;
> +
> + /*
> + * If selection is not implemented,
> + * fallback by enumerating sensor frame sizes
> + * and take the largest one
> + */
> + max_width = 0;
> + max_height = 0;
> + max_pixsize = 0;
> + for (i = 0; i < dcmi->nb_of_sd_framesizes; i++) {
> + struct dcmi_framesize *fsize = &dcmi->sd_framesizes[i];
> + unsigned int pixsize = fsize->width * fsize->height;
> +
> + if (pixsize > max_pixsize) {
> + max_pixsize = pixsize;
> + max_width = fsize->width;
> + max_height = fsize->height;
> + }
> + }
> + if (max_pixsize > 0) {
> + r->top = 0;
> + r->left = 0;
> + r->width = max_width;
> + r->height = max_height;
> + return 0;
> + }
> +
> + /*
> + * If frame sizes enumeration is not implemented,
> + * fallback by getting current sensor frame size
> + */
> + ret = dcmi_get_sensor_format(dcmi, &pix);
> + if (ret)
> + return ret;
> +
> + r->top = 0;
> + r->left = 0;
> + r->width = pix.width;
> + r->height = pix.height;
> +
> + return 0;
> +}
> +
> +static int dcmi_g_selection(struct file *file, void *fh,
> + struct v4l2_selection *s)
> +{
> + struct stm32_dcmi *dcmi = video_drvdata(file);
> + struct v4l2_rect crop;
> +
> + if (s->type != V4L2_BUF_TYPE_VIDEO_CAPTURE)
> + return -EINVAL;
> +
> + if (dcmi->do_crop) {
> + crop = dcmi->crop;
> + } else {
> + crop.top = 0;
> + crop.left = 0;
> + crop.width = dcmi->fmt.fmt.pix.width;
> + crop.height = dcmi->fmt.fmt.pix.height;
> + }
Just move this down to the V4L2_SEL_TGT_CROP case:
if (dcmi->do_crop) {
s->r = dcmi->crop;
} else {
...
}
> +
> + switch (s->target) {
> + case V4L2_SEL_TGT_CROP_DEFAULT:
> + case V4L2_SEL_TGT_CROP_BOUNDS:
> + s->r = dcmi->sd_bounds;
> + return 0;
> + case V4L2_SEL_TGT_CROP:
> + s->r = crop;
> + break;
> + default:
> + return -EINVAL;
> + }
> +
> + return 0;
> +}
> +
> +static int dcmi_s_selection(struct file *file, void *priv,
> + struct v4l2_selection *s)
> +{
> + struct stm32_dcmi *dcmi = video_drvdata(file);
> + struct v4l2_rect r = s->r;
> + struct v4l2_rect max_rect;
> + struct v4l2_pix_format pix;
> +
> + if (s->type != V4L2_BUF_TYPE_VIDEO_CAPTURE ||
> + s->target != V4L2_SEL_TGT_CROP)
> + return -EINVAL;
> +
> + /* Reset sensor resolution to max resolution */
> + pix.pixelformat = dcmi->fmt.fmt.pix.pixelformat;
> + pix.width = dcmi->sd_bounds.width;
> + pix.height = dcmi->sd_bounds.height;
> + dcmi_set_sensor_format(dcmi, &pix);
> +
> + /*
> + * Make the intersection between
> + * sensor resolution
> + * and crop request
> + */
> + max_rect.top = 0;
> + max_rect.left = 0;
> + max_rect.width = pix.width;
> + max_rect.height = pix.height;
> + v4l2_rect_map_inside(&r, &max_rect);
> + r.top = clamp_t(s32, r.top, 0, pix.height - r.height);
> + r.left = clamp_t(s32, r.left, 0, pix.width - r.width);
> +
> + dcmi->crop = r;
> + s->r = r;
> + dcmi->do_crop = true;
Hmm, isn't do_crop only true if s->r != dcmi->sd_bounds?
I.e. if you call s_selection with 640x480, then that means to stop
cropping.
> +
> + dev_dbg(dcmi->dev, "s_selection: crop %ux%u@(%u,%u) from %ux%u\n",
> + r.width, r.height, r.left, r.top, pix.width, pix.height);
> +
> + return 0;
> +}
> +
> static int dcmi_querycap(struct file *file, void *priv,
> struct v4l2_capability *cap)
> {
> @@ -903,7 +1203,7 @@ static int dcmi_set_default_fmt(struct stm32_dcmi *dcmi)
> };
> int ret;
>
> - ret = dcmi_try_fmt(dcmi, &f, NULL);
> + ret = dcmi_try_fmt(dcmi, &f, NULL, NULL);
> if (ret)
> return ret;
> dcmi->sd_format = dcmi->sd_formats[0];
> @@ -938,6 +1238,8 @@ static int dcmi_open(struct file *file)
> if (ret < 0 && ret != -ENOIOCTLCMD)
> goto fh_rel;
>
> + dcmi->do_crop = false;
> +
Same as my comment in the previous patch: opening a video device should have no
effect on the internal state.
> ret = dcmi_set_default_fmt(dcmi);
> if (ret)
> goto power_off;
> @@ -983,6 +1285,8 @@ static int dcmi_release(struct file *file)
> .vidioc_g_fmt_vid_cap = dcmi_g_fmt_vid_cap,
> .vidioc_s_fmt_vid_cap = dcmi_s_fmt_vid_cap,
> .vidioc_enum_fmt_vid_cap = dcmi_enum_fmt_vid_cap,
> + .vidioc_g_selection = dcmi_g_selection,
> + .vidioc_s_selection = dcmi_s_selection,
>
> .vidioc_enum_input = dcmi_enum_input,
> .vidioc_g_input = dcmi_g_input,
> @@ -1082,6 +1386,49 @@ static int dcmi_formats_init(struct stm32_dcmi *dcmi)
> return 0;
> }
>
> +static int dcmi_framesizes_init(struct stm32_dcmi *dcmi)
> +{
> + unsigned int num_fsize = 0;
> + struct v4l2_subdev *subdev = dcmi->entity.subdev;
> + struct v4l2_subdev_frame_size_enum fse = {
> + .which = V4L2_SUBDEV_FORMAT_ACTIVE,
> + .code = dcmi->sd_format->mbus_code,
> + };
> + unsigned int ret;
> + unsigned int i;
> +
> + /* Allocate discrete framesizes array */
> + while (!v4l2_subdev_call(subdev, pad, enum_frame_size,
> + NULL, &fse))
> + fse.index++;
> +
> + num_fsize = fse.index;
> + if (!num_fsize)
> + return 0;
> +
> + dcmi->nb_of_sd_framesizes = num_fsize;
> + dcmi->sd_framesizes = devm_kcalloc(dcmi->dev, num_fsize,
> + sizeof(struct dcmi_framesize),
> + GFP_KERNEL);
> + if (!dcmi->sd_framesizes) {
> + dev_err(dcmi->dev, "Could not allocate memory\n");
> + return -ENOMEM;
> + }
> +
> + /* Fill array with sensor supported framesizes */
> + dev_dbg(dcmi->dev, "Sensor supports %u frame sizes:\n", num_fsize);
> + for (i = 0; i < dcmi->nb_of_sd_framesizes; i++) {
> + fse.index = i;
> + if (v4l2_subdev_call(subdev, pad, enum_frame_size, NULL, &fse))
> + return ret;
As the kbuild post said: ret is uninitialized here.
> + dcmi->sd_framesizes[fse.index].width = fse.max_width;
> + dcmi->sd_framesizes[fse.index].height = fse.max_height;
> + dev_dbg(dcmi->dev, "%ux%u\n", fse.max_width, fse.max_height);
> + }
> +
> + return 0;
> +}
> +
> static int dcmi_graph_notify_complete(struct v4l2_async_notifier *notifier)
> {
> struct stm32_dcmi *dcmi = notifier_to_dcmi(notifier);
> @@ -1094,6 +1441,18 @@ static int dcmi_graph_notify_complete(struct v4l2_async_notifier *notifier)
> return ret;
> }
>
> + ret = dcmi_framesizes_init(dcmi);
> + if (ret) {
> + dev_err(dcmi->dev, "Could not initialize framesizes\n");
> + return ret;
> + }
> +
> + ret = dcmi_get_sensor_bounds(dcmi, &dcmi->sd_bounds);
> + if (ret) {
> + dev_err(dcmi->dev, "Could not get sensor bounds\n");
> + return ret;
> + }
> +
> ret = dcmi_set_default_fmt(dcmi);
> if (ret) {
> dev_err(dcmi->dev, "Could not set default format\n");
>
OK, I'll have another look once v2 is posted. Always tricky code to review...
Regards,
Hans