diff mbox series

[v4,07/11] media: atmel: atmel-isc: change format propagation to subdev into only verification

Message ID 20220121131416.603972-8-eugen.hristev@microchip.com (mailing list archive)
State New, archived
Headers show
Series media: atmel: atmel-isc: implement media controller | expand

Commit Message

Eugen Hristev Jan. 21, 2022, 1:14 p.m. UTC
As a top MC video driver, the atmel-isc should not propagate the format to the
subdevice.
It should rather check at start_streaming() time if the subdev is properly
configured with a compatible format.
Removed the whole format finding logic, and reworked the format verification
at start_streaming time, such that the ISC will return an error if the subdevice
is not properly configured. To achieve this, media_pipeline_start
is called and a link_validate callback is created to check the formats.
With this being done, the module parameter 'sensor_preferred' makes no sense
anymore. The ISC should not decide which format the sensor is using. The
ISC should only cope with the situation and inform userspace if the streaming
is possible in the current configuration.
The redesign of the format propagation has also risen the question of the
enumfmt callback. If enumfmt is called with an mbus_code, the enumfmt handler
should only return the formats that are supported for this mbus_code.
To make it more easy to understand the formats, changed the report order
to report first the native formats, and after that the formats that the ISC
can convert to.

Signed-off-by: Eugen Hristev <eugen.hristev@microchip.com>
---
Changes in v4:
- moved validation code into link_validate and used media_pipeline_start
- merged this patch with the enum_fmt patch which was previously in v3 of
the series

Changes in v3:
- clamp to maximum resolution once the frame size from the subdev is found

 drivers/media/platform/atmel/atmel-isc-base.c | 335 ++++++++++--------
 .../media/platform/atmel/atmel-isc-scaler.c   |   5 +
 drivers/media/platform/atmel/atmel-isc.h      |   3 +
 3 files changed, 191 insertions(+), 152 deletions(-)

Comments

Jacopo Mondi Feb. 10, 2022, 6:43 p.m. UTC | #1
Hi Eugen

On Fri, Jan 21, 2022 at 03:14:12PM +0200, Eugen Hristev wrote:
> As a top MC video driver, the atmel-isc should not propagate the format to the
> subdevice.
> It should rather check at start_streaming() time if the subdev is properly
> configured with a compatible format.
> Removed the whole format finding logic, and reworked the format verification
> at start_streaming time, such that the ISC will return an error if the subdevice
> is not properly configured. To achieve this, media_pipeline_start
> is called and a link_validate callback is created to check the formats.
> With this being done, the module parameter 'sensor_preferred' makes no sense
> anymore. The ISC should not decide which format the sensor is using. The
> ISC should only cope with the situation and inform userspace if the streaming
> is possible in the current configuration.

This sounds right!

> The redesign of the format propagation has also risen the question of the
> enumfmt callback. If enumfmt is called with an mbus_code, the enumfmt handler
> should only return the formats that are supported for this mbus_code.
> To make it more easy to understand the formats, changed the report order
> to report first the native formats, and after that the formats that the ISC
> can convert to.
>
> Signed-off-by: Eugen Hristev <eugen.hristev@microchip.com>
> ---
> Changes in v4:
> - moved validation code into link_validate and used media_pipeline_start
> - merged this patch with the enum_fmt patch which was previously in v3 of
> the series
>
> Changes in v3:
> - clamp to maximum resolution once the frame size from the subdev is found
>
>  drivers/media/platform/atmel/atmel-isc-base.c | 335 ++++++++++--------
>  .../media/platform/atmel/atmel-isc-scaler.c   |   5 +
>  drivers/media/platform/atmel/atmel-isc.h      |   3 +
>  3 files changed, 191 insertions(+), 152 deletions(-)
>
> diff --git a/drivers/media/platform/atmel/atmel-isc-base.c b/drivers/media/platform/atmel/atmel-isc-base.c
> index f7a88399bd54..31c79313aadc 100644
> --- a/drivers/media/platform/atmel/atmel-isc-base.c
> +++ b/drivers/media/platform/atmel/atmel-isc-base.c
> @@ -36,11 +36,6 @@ static unsigned int debug;
>  module_param(debug, int, 0644);
>  MODULE_PARM_DESC(debug, "debug level (0-2)");
>
> -static unsigned int sensor_preferred = 1;
> -module_param(sensor_preferred, uint, 0644);
> -MODULE_PARM_DESC(sensor_preferred,
> -		 "Sensor is preferred to output the specified format (1-on 0-off), default 1");
> -
>  #define ISC_IS_FORMAT_RAW(mbus_code) \
>  	(((mbus_code) & 0xf000) == 0x3000)
>
> @@ -337,6 +332,10 @@ static int isc_start_streaming(struct vb2_queue *vq, unsigned int count)
>  	unsigned long flags;
>  	int ret;
>
> +	ret = media_pipeline_start(&isc->video_dev.entity, &isc->mpipe);
> +	if (ret)
> +		goto err_pipeline_start;
> +
>  	/* Enable stream on the sub device */
>  	ret = v4l2_subdev_call(isc->current_subdev->sd, video, s_stream, 1);
>  	if (ret && ret != -ENOIOCTLCMD) {
> @@ -384,6 +383,9 @@ static int isc_start_streaming(struct vb2_queue *vq, unsigned int count)
>  	v4l2_subdev_call(isc->current_subdev->sd, video, s_stream, 0);
>
>  err_start_stream:
> +	media_pipeline_stop(&isc->video_dev.entity);
> +
> +err_pipeline_start:
>  	spin_lock_irqsave(&isc->dma_queue_lock, flags);
>  	list_for_each_entry(buf, &isc->dma_queue, list)
>  		vb2_buffer_done(&buf->vb.vb2_buf, VB2_BUF_STATE_QUEUED);
> @@ -420,6 +422,9 @@ static void isc_stop_streaming(struct vb2_queue *vq)
>  	if (ret && ret != -ENOIOCTLCMD)
>  		v4l2_err(&isc->v4l2_dev, "stream off failed in subdev\n");
>
> +	/* Stop media pipeline */
> +	media_pipeline_stop(&isc->video_dev.entity);
> +
>  	/* Release all active buffers */
>  	spin_lock_irqsave(&isc->dma_queue_lock, flags);
>  	if (unlikely(isc->cur_frm)) {
> @@ -496,21 +501,56 @@ static int isc_enum_fmt_vid_cap(struct file *file, void *priv,
>  	u32 index = f->index;
>  	u32 i, supported_index;
>
> -	if (index < isc->controller_formats_size) {
> -		f->pixelformat = isc->controller_formats[index].fourcc;
> -		return 0;
> +	supported_index = 0;
> +
> +	for (i = 0; i < isc->formats_list_size; i++) {
> +		if (!isc->formats_list[i].sd_support)
> +			continue;

Sorry to ask again about sd_support, but if the ISC formats
enumeration is not constrained to a specific mbus_code, shouldn't all
the formats be enumerated regardless if they're supported from the
sensor or not ?

> +		/*
> +		 * If specific mbus_code is requested, provide only
> +		 * supported formats with this mbus code
> +		 */
> +		if (f->mbus_code && f->mbus_code !=
> +		    isc->formats_list[i].mbus_code)

nit: for clarity
		if (f->mbus_code &&
                    f->mbus_code != isc->formats_list[i].mbus_code)

> +			continue;
> +		if (supported_index == index) {
> +			f->pixelformat = isc->formats_list[i].fourcc;
> +			return 0;
> +		}
> +		supported_index++;
>  	}
>
> -	index -= isc->controller_formats_size;
> +	/*
> +	 * If the sensor does not support this mbus_code whatsoever,
> +	 * there is no reason to advertise any of our output formats
> +	 */
> +	if (supported_index == 0)
> +		return -EINVAL;
>
> +	/*
> +	 * If the sensor uses a format that is not raw, then we cannot
> +	 * convert it to any of the formats that we usually can with a
> +	 * RAW sensor. Thus, do not advertise them.
> +	 */
> +	if (isc->config.sd_format &&
> +	    !ISC_IS_FORMAT_RAW(isc->config.sd_format->mbus_code))
> +		return -EINVAL;
> +
> +	/*
> +	 * Iterate again through the formats that we can convert to.
> +	 * However, to avoid duplicates, skip the formats that
> +	 * the sensor already supports directly
> +	 */
> +	index -= supported_index;
>  	supported_index = 0;
>
> -	for (i = 0; i < isc->formats_list_size; i++) {
> -		if (!ISC_IS_FORMAT_RAW(isc->formats_list[i].mbus_code) ||
> -		    !isc->formats_list[i].sd_support)
> +	for (i = 0; i < isc->controller_formats_size; i++) {
> +		/* if this format is already supported by sensor, skip it */
> +		if (find_format_by_fourcc(isc, isc->controller_formats[i].fourcc))
>  			continue;
>  		if (supported_index == index) {
> -			f->pixelformat = isc->formats_list[i].fourcc;
> +			f->pixelformat =
> +				isc->controller_formats[i].fourcc;

I trust this last part to work correctly, as it's not 100% clear to me :)

>  			return 0;
>  		}
>  		supported_index++;
> @@ -581,20 +621,30 @@ static int isc_try_validate_formats(struct isc_device *isc)
>  		break;
>  	default:
>  	/* any other different formats are not supported */
> +		v4l2_err(&isc->v4l2_dev, "Requested unsupported format.\n");
>  		ret = -EINVAL;
>  	}
>  	v4l2_dbg(1, debug, &isc->v4l2_dev,
>  		 "Format validation, requested rgb=%u, yuv=%u, grey=%u, bayer=%u\n",
>  		 rgb, yuv, grey, bayer);
>
> -	/* we cannot output RAW if we do not receive RAW */
> -	if ((bayer) && !ISC_IS_FORMAT_RAW(isc->try_config.sd_format->mbus_code))
> +	if ((bayer) &&

just 'bayer' ?

> +	    !ISC_IS_FORMAT_RAW(isc->try_config.sd_format->mbus_code)) {
> +		v4l2_err(&isc->v4l2_dev, "Cannot output RAW if we do not receive RAW.\n");
>  		return -EINVAL;
> +	}
>
> -	/* we cannot output GREY if we do not receive RAW/GREY */
>  	if (grey && !ISC_IS_FORMAT_RAW(isc->try_config.sd_format->mbus_code) &&
> -	    !ISC_IS_FORMAT_GREY(isc->try_config.sd_format->mbus_code))
> +	    !ISC_IS_FORMAT_GREY(isc->try_config.sd_format->mbus_code)) {
> +		v4l2_err(&isc->v4l2_dev, "Cannot output GREY if we do not receive RAW/GREY.\n");
> +		return -EINVAL;
> +	}
> +
> +	if ((rgb || bayer || yuv) &&
> +	    ISC_IS_FORMAT_GREY(isc->try_config.sd_format->mbus_code)) {
> +		v4l2_err(&isc->v4l2_dev, "Cannot convert GREY to another format.\n");
>  		return -EINVAL;
> +	}
>
>  	return ret;
>  }
> @@ -822,7 +872,7 @@ static void isc_try_fse(struct isc_device *isc,
>  	 * If we do not know yet which format the subdev is using, we cannot
>  	 * do anything.
>  	 */
> -	if (!isc->try_config.sd_format)
> +	if (!isc->config.sd_format)
>  		return;
>
>  	fse.code = isc->try_config.sd_format->mbus_code;
> @@ -843,180 +893,141 @@ static void isc_try_fse(struct isc_device *isc,
>  	}
>  }
>
> -static int isc_try_fmt(struct isc_device *isc, struct v4l2_format *f,
> -			u32 *code)
> +static int isc_try_fmt(struct isc_device *isc, struct v4l2_format *f)
>  {
> -	int i;
> -	struct isc_format *sd_fmt = NULL, *direct_fmt = NULL;
>  	struct v4l2_pix_format *pixfmt = &f->fmt.pix;
> -	struct v4l2_subdev_pad_config pad_cfg = {};
> -	struct v4l2_subdev_state pad_state = {
> -		.pads = &pad_cfg
> -		};
> -	struct v4l2_subdev_format format = {
> -		.which = V4L2_SUBDEV_FORMAT_TRY,
> -	};
> -	u32 mbus_code;
> -	int ret;
> -	bool rlp_dma_direct_dump = false;
> +	unsigned int i;
>
>  	if (f->type != V4L2_BUF_TYPE_VIDEO_CAPTURE)
>  		return -EINVAL;
>
> -	/* Step 1: find a RAW format that is supported */
> -	for (i = 0; i < isc->num_user_formats; i++) {
> -		if (ISC_IS_FORMAT_RAW(isc->user_formats[i]->mbus_code)) {
> -			sd_fmt = isc->user_formats[i];
> +	isc->try_config.fourcc = isc->user_formats[0]->fourcc;
> +
> +	/* find if the format requested is supported */
> +	for (i = 0; i < isc->controller_formats_size; i++)
> +		if (isc->controller_formats[i].fourcc == pixfmt->pixelformat) {
> +			isc->try_config.fourcc = pixfmt->pixelformat;
>  			break;
>  		}
> -	}
> -	/* Step 2: We can continue with this RAW format, or we can look
> -	 * for better: maybe sensor supports directly what we need.
> -	 */
> -	direct_fmt = find_format_by_fourcc(isc, pixfmt->pixelformat);
> -
> -	/* Step 3: We have both. We decide given the module parameter which
> -	 * one to use.
> -	 */
> -	if (direct_fmt && sd_fmt && sensor_preferred)
> -		sd_fmt = direct_fmt;
> -
> -	/* Step 4: we do not have RAW but we have a direct format. Use it. */
> -	if (direct_fmt && !sd_fmt)
> -		sd_fmt = direct_fmt;
> -
> -	/* Step 5: if we are using a direct format, we need to package
> -	 * everything as 8 bit data and just dump it
> -	 */
> -	if (sd_fmt == direct_fmt)
> -		rlp_dma_direct_dump = true;
> -
> -	/* Step 6: We have no format. This can happen if the userspace
> -	 * requests some weird/invalid format.
> -	 * In this case, default to whatever we have
> -	 */
> -	if (!sd_fmt && !direct_fmt) {
> -		sd_fmt = isc->user_formats[isc->num_user_formats - 1];
> -		v4l2_dbg(1, debug, &isc->v4l2_dev,
> -			 "Sensor not supporting %.4s, using %.4s\n",
> -			 (char *)&pixfmt->pixelformat, (char *)&sd_fmt->fourcc);
> -	}
> -
> -	if (!sd_fmt) {
> -		ret = -EINVAL;
> -		goto isc_try_fmt_err;
> -	}
> -
> -	/* Step 7: Print out what we decided for debugging */
> -	v4l2_dbg(1, debug, &isc->v4l2_dev,
> -		 "Preferring to have sensor using format %.4s\n",
> -		 (char *)&sd_fmt->fourcc);
> -
> -	/* Step 8: at this moment we decided which format the subdev will use */
> -	isc->try_config.sd_format = sd_fmt;
> -
> -	/* Limit to Atmel ISC hardware capabilities */
> -	if (pixfmt->width > isc->max_width)
> -		pixfmt->width = isc->max_width;
> -	if (pixfmt->height > isc->max_height)
> -		pixfmt->height = isc->max_height;
> -
> -	/*
> -	 * The mbus format is the one the subdev outputs.
> -	 * The pixels will be transferred in this format Sensor -> ISC
> -	 */
> -	mbus_code = sd_fmt->mbus_code;
> -
> -	/*
> -	 * Validate formats. If the required format is not OK, default to raw.
> -	 */
> -
> -	isc->try_config.fourcc = pixfmt->pixelformat;
> -
> -	if (isc_try_validate_formats(isc)) {
> -		pixfmt->pixelformat = isc->try_config.fourcc = sd_fmt->fourcc;
> -		/* Re-try to validate the new format */
> -		ret = isc_try_validate_formats(isc);
> -		if (ret)
> -			goto isc_try_fmt_err;
> -	}
> -
> -	ret = isc_try_configure_rlp_dma(isc, rlp_dma_direct_dump);
> -	if (ret)
> -		goto isc_try_fmt_err;
> -
> -	ret = isc_try_configure_pipeline(isc);
> -	if (ret)
> -		goto isc_try_fmt_err;
>
> -	/* Obtain frame sizes if possible to have crop requirements ready */
> -	isc_try_fse(isc, &pad_state);
> -
> -	v4l2_fill_mbus_format(&format.format, pixfmt, mbus_code);
> -	ret = v4l2_subdev_call(isc->current_subdev->sd, pad, set_fmt,
> -			       &pad_state, &format);
> -	if (ret < 0)
> -		goto isc_try_fmt_subdev_err;
> +	/* If we did not find the requested format, we will fallback here */
> +	pixfmt->pixelformat = isc->try_config.fourcc;
> +	pixfmt->colorspace = V4L2_COLORSPACE_SRGB;
> +	pixfmt->field = V4L2_FIELD_NONE;
>
> -	v4l2_fill_pix_format(pixfmt, &format.format);
> +	isc_try_configure_rlp_dma(isc, false);
>
>  	/* Limit to Atmel ISC hardware capabilities */
> -	if (pixfmt->width > isc->max_width)
> -		pixfmt->width = isc->max_width;
> -	if (pixfmt->height > isc->max_height)
> -		pixfmt->height = isc->max_height;
> +	v4l_bound_align_image(&pixfmt->width, 16, isc->max_width, 0,
> +			      &pixfmt->height, 16, isc->max_height, 0, 0);
>
>  	pixfmt->field = V4L2_FIELD_NONE;
>  	pixfmt->bytesperline = (pixfmt->width * isc->try_config.bpp_v4l2) >> 3;
>  	pixfmt->sizeimage = ((pixfmt->width * isc->try_config.bpp) >> 3) *
>  			     pixfmt->height;

Seems pixfmt->field is set twice.

Could you move the assignment of all pixfmt to a single block ?

>
> -	if (code)
> -		*code = mbus_code;
> +	isc->try_fmt = *f;
>
>  	return 0;
> +}
>
> -isc_try_fmt_err:
> -	v4l2_err(&isc->v4l2_dev, "Could not find any possible format for a working pipeline\n");
> -isc_try_fmt_subdev_err:
> -	memset(&isc->try_config, 0, sizeof(isc->try_config));
> +static int isc_set_fmt(struct isc_device *isc, struct v4l2_format *f)
> +{
> +	isc_try_fmt(isc, f);
>
> -	return ret;
> +	/* make the try configuration active */
> +	isc->config = isc->try_config;
> +	isc->fmt = isc->try_fmt;
> +
> +	v4l2_dbg(1, debug, &isc->v4l2_dev, "ISC set_fmt to %.4s @%dx%d\n",
> +		 (char *)&f->fmt.pix.pixelformat,
> +		 f->fmt.pix.width, f->fmt.pix.height);
> +
> +	return 0;
>  }
>
> -static int isc_set_fmt(struct isc_device *isc, struct v4l2_format *f)
> +static int isc_validate(struct isc_device *isc)
>  {
> +	int ret;
> +	int i;
> +	struct isc_format *sd_fmt = NULL;
> +	struct v4l2_pix_format *pixfmt = &isc->fmt.fmt.pix;
>  	struct v4l2_subdev_format format = {
>  		.which = V4L2_SUBDEV_FORMAT_ACTIVE,
> +		.pad = isc->remote_pad,
> +	};
> +	struct v4l2_subdev_pad_config pad_cfg = {};
> +	struct v4l2_subdev_state pad_state = {
> +		.pads = &pad_cfg,
>  	};
> -	u32 mbus_code = 0;
> -	int ret;
>
> -	ret = isc_try_fmt(isc, f, &mbus_code);
> +	/* Get current format from subdev */
> +	ret = v4l2_subdev_call(isc->current_subdev->sd, pad, get_fmt, NULL,
> +			       &format);
>  	if (ret)
>  		return ret;
>
> -	v4l2_fill_mbus_format(&format.format, &f->fmt.pix, mbus_code);
> -	ret = v4l2_subdev_call(isc->current_subdev->sd, pad,
> -			       set_fmt, NULL, &format);
> -	if (ret < 0)
> -		return ret;
> +	/* Identify the subdev's format configuration */
> +	for (i = 0; i < isc->num_user_formats; i++)
> +		if (isc->user_formats[i]->mbus_code == format.format.code) {
> +			sd_fmt = isc->user_formats[i];
> +			break;
> +		}
> +
> +	/* Check if the format is not supported */
> +	if (!sd_fmt) {
> +		v4l2_err(&isc->v4l2_dev,
> +			 "Current subdevice is streaming a media bus code that is not supported 0x%x\n",
> +			 format.format.code);
> +		return -EPIPE;
> +	}
> +
> +	/* At this moment we know which format the subdev will use */
> +	isc->try_config.sd_format = sd_fmt;
> +
> +	/* If the sensor is not RAW, we can only do a direct dump */
> +	if (!ISC_IS_FORMAT_RAW(isc->try_config.sd_format->mbus_code))
> +		isc_try_configure_rlp_dma(isc, true);
>
>  	/* Limit to Atmel ISC hardware capabilities */
> -	if (f->fmt.pix.width > isc->max_width)
> -		f->fmt.pix.width = isc->max_width;
> -	if (f->fmt.pix.height > isc->max_height)
> -		f->fmt.pix.height = isc->max_height;
> +	v4l_bound_align_image(&format.format.width, 16, isc->max_width, 0,
> +			      &format.format.height, 16, isc->max_height, 0, 0);
> +
> +	/* Check if the frame size is the same. Otherwise we may overflow */
> +	if (pixfmt->height != format.format.height ||
> +	    pixfmt->width != format.format.width) {
> +		v4l2_err(&isc->v4l2_dev,
> +			 "ISC not configured with the proper frame size: %dx%d\n",
> +			 format.format.width, format.format.height);
> +		return -EPIPE;
> +	}
>
> -	isc->fmt = *f;
> +	v4l2_dbg(1, debug, &isc->v4l2_dev,
> +		 "Identified subdev using format %.4s with %dx%d %d bpp\n",
> +		 (char *)&sd_fmt->fourcc, pixfmt->width, pixfmt->height,
> +		 isc->try_config.bpp);
>
> +	/* Reset and restart AWB if the subdevice changed the format */
>  	if (isc->try_config.sd_format && isc->config.sd_format &&
>  	    isc->try_config.sd_format != isc->config.sd_format) {
>  		isc->ctrls.hist_stat = HIST_INIT;
>  		isc_reset_awb_ctrls(isc);
>  		isc_update_v4l2_ctrls(isc);
>  	}
> -	/* make the try configuration active */
> +
> +	/* Validate formats */
> +	ret = isc_try_validate_formats(isc);
> +	if (ret)
> +		return ret;
> +
> +	/* Obtain frame sizes if possible to have crop requirements ready */
> +	isc_try_fse(isc, &pad_state);
> +
> +	/* Configure ISC pipeline for the config */
> +	ret = isc_try_configure_pipeline(isc);
> +	if (ret)
> +		return ret;
> +
>  	isc->config = isc->try_config;
>
>  	v4l2_dbg(1, debug, &isc->v4l2_dev, "New ISC configuration in place\n");
> @@ -1040,7 +1051,7 @@ static int isc_try_fmt_vid_cap(struct file *file, void *priv,
>  {
>  	struct isc_device *isc = video_drvdata(file);
>
> -	return isc_try_fmt(isc, f, NULL);
> +	return isc_try_fmt(isc, f);
>  }
>
>  static int isc_enum_input(struct file *file, void *priv,
> @@ -1841,7 +1852,7 @@ static int isc_set_default_fmt(struct isc_device *isc)
>  	};
>  	int ret;
>
> -	ret = isc_try_fmt(isc, &f, NULL);
> +	ret = isc_try_fmt(isc, &f);
>  	if (ret)
>  		return ret;
>
> @@ -2015,6 +2026,24 @@ int isc_pipeline_init(struct isc_device *isc)
>  }
>  EXPORT_SYMBOL_GPL(isc_pipeline_init);
>
> +int isc_link_validate(struct media_link *link)
> +{
> +	struct video_device *vdev =
> +		media_entity_to_video_device(link->sink->entity);
> +	struct isc_device *isc = video_get_drvdata(vdev);
> +	int ret;
> +
> +	ret = v4l2_subdev_link_validate(link);
> +	if (ret)
> +		return ret;

Doesn't v4l2_subdev_link_validate() call
v4l2_subdev_link_validate_default() if you don't define a .link_validate()
pad operation ? v4l2_subdev_link_validate_default() compares format
and sizes of both ends to the links and want them to be identical,
something that defeat the purpose of your custom isc_validate() ?

Thanks
  j

> +
> +	return isc_validate(isc);
> +}
> +
> +static const struct media_entity_operations isc_entity_operations = {
> +	.link_validate = isc_link_validate,
> +};
> +
};
>  int isc_mc_init(struct isc_device *isc, u32 ver)
>  {
>  	const struct of_device_id *match;
> @@ -2022,6 +2051,8 @@ int isc_mc_init(struct isc_device *isc, u32 ver)
>
>  	isc->video_dev.entity.function = MEDIA_ENT_F_IO_V4L;
>  	isc->video_dev.entity.flags = MEDIA_ENT_FL_DEFAULT;
> +	isc->video_dev.entity.ops = &isc_entity_operations;
> +
>  	isc->pads[ISC_PAD_SINK].flags = MEDIA_PAD_FL_SINK;
>
>  	ret = media_entity_pads_init(&isc->video_dev.entity, ISC_PADS_NUM,
> diff --git a/drivers/media/platform/atmel/atmel-isc-scaler.c b/drivers/media/platform/atmel/atmel-isc-scaler.c
> index ec95c9665883..93375a61aea6 100644
> --- a/drivers/media/platform/atmel/atmel-isc-scaler.c
> +++ b/drivers/media/platform/atmel/atmel-isc-scaler.c
> @@ -155,6 +155,10 @@ static const struct v4l2_subdev_pad_ops isc_scaler_pad_ops = {
>  	.init_cfg = isc_scaler_init_cfg,
>  };
>
> +static const struct media_entity_operations isc_scaler_entity_ops = {
> +	.link_validate = v4l2_subdev_link_validate,
> +};
> +
>  static const struct v4l2_subdev_ops xisc_scaler_subdev_ops = {
>  	.pad = &isc_scaler_pad_ops,
>  };
> @@ -172,6 +176,7 @@ int isc_scaler_init(struct isc_device *isc)
>
>  	isc->scaler_sd.flags |= V4L2_SUBDEV_FL_HAS_DEVNODE;
>  	isc->scaler_sd.entity.function = MEDIA_ENT_F_PROC_VIDEO_SCALER;
> +	isc->scaler_sd.entity.ops = &isc_scaler_entity_ops;
>  	isc->scaler_pads[ISC_SCALER_PAD_SINK].flags = MEDIA_PAD_FL_SINK;
>  	isc->scaler_pads[ISC_SCALER_PAD_SOURCE].flags = MEDIA_PAD_FL_SOURCE;
>
> diff --git a/drivers/media/platform/atmel/atmel-isc.h b/drivers/media/platform/atmel/atmel-isc.h
> index 04ea5e340808..e36cf9d3942a 100644
> --- a/drivers/media/platform/atmel/atmel-isc.h
> +++ b/drivers/media/platform/atmel/atmel-isc.h
> @@ -270,6 +270,7 @@ enum isc_scaler_pads {
>   * @formats_list_size:	size of formats_list array
>   * @pads:		media controller pads for isc video entity
>   * @mdev:		media device that is registered by the isc
> + * @mpipe:		media device pipeline used by the isc
>   * @remote_pad:		remote pad on the connected subdevice
>   * @scaler_sd:		subdevice for the scaler that isc registers
>   * @scaler_pads:	media controller pads for the scaler subdevice
> @@ -295,6 +296,7 @@ struct isc_device {
>  	struct completion	comp;
>
>  	struct v4l2_format	fmt;
> +	struct v4l2_format	try_fmt;
>  	struct isc_format	**user_formats;
>  	unsigned int		num_user_formats;
>
> @@ -366,6 +368,7 @@ struct isc_device {
>  	struct {
>  		struct media_pad		pads[ISC_PADS_NUM];
>  		struct media_device		mdev;
> +		struct media_pipeline		mpipe;
>
>  		u32				remote_pad;
>  	};
> --
> 2.25.1
>
Eugen Hristev Feb. 11, 2022, 10:38 a.m. UTC | #2
On 2/10/22 8:43 PM, Jacopo Mondi wrote:
> Hi Eugen
> 
> On Fri, Jan 21, 2022 at 03:14:12PM +0200, Eugen Hristev wrote:
>> As a top MC video driver, the atmel-isc should not propagate the format to the
>> subdevice.
>> It should rather check at start_streaming() time if the subdev is properly
>> configured with a compatible format.
>> Removed the whole format finding logic, and reworked the format verification
>> at start_streaming time, such that the ISC will return an error if the subdevice
>> is not properly configured. To achieve this, media_pipeline_start
>> is called and a link_validate callback is created to check the formats.
>> With this being done, the module parameter 'sensor_preferred' makes no sense
>> anymore. The ISC should not decide which format the sensor is using. The
>> ISC should only cope with the situation and inform userspace if the streaming
>> is possible in the current configuration.
> 
> This sounds right!
> 
>> The redesign of the format propagation has also risen the question of the
>> enumfmt callback. If enumfmt is called with an mbus_code, the enumfmt handler
>> should only return the formats that are supported for this mbus_code.
>> To make it more easy to understand the formats, changed the report order
>> to report first the native formats, and after that the formats that the ISC
>> can convert to.
>>
>> Signed-off-by: Eugen Hristev <eugen.hristev@microchip.com>
>> ---
>> Changes in v4:
>> - moved validation code into link_validate and used media_pipeline_start
>> - merged this patch with the enum_fmt patch which was previously in v3 of
>> the series
>>
>> Changes in v3:
>> - clamp to maximum resolution once the frame size from the subdev is found
>>
>>   drivers/media/platform/atmel/atmel-isc-base.c | 335 ++++++++++--------
>>   .../media/platform/atmel/atmel-isc-scaler.c   |   5 +
>>   drivers/media/platform/atmel/atmel-isc.h      |   3 +
>>   3 files changed, 191 insertions(+), 152 deletions(-)
>>
>> diff --git a/drivers/media/platform/atmel/atmel-isc-base.c b/drivers/media/platform/atmel/atmel-isc-base.c
>> index f7a88399bd54..31c79313aadc 100644
>> --- a/drivers/media/platform/atmel/atmel-isc-base.c
>> +++ b/drivers/media/platform/atmel/atmel-isc-base.c
>> @@ -36,11 +36,6 @@ static unsigned int debug;
>>   module_param(debug, int, 0644);
>>   MODULE_PARM_DESC(debug, "debug level (0-2)");
>>
>> -static unsigned int sensor_preferred = 1;
>> -module_param(sensor_preferred, uint, 0644);
>> -MODULE_PARM_DESC(sensor_preferred,
>> -              "Sensor is preferred to output the specified format (1-on 0-off), default 1");
>> -
>>   #define ISC_IS_FORMAT_RAW(mbus_code) \
>>        (((mbus_code) & 0xf000) == 0x3000)
>>
>> @@ -337,6 +332,10 @@ static int isc_start_streaming(struct vb2_queue *vq, unsigned int count)
>>        unsigned long flags;
>>        int ret;
>>
>> +     ret = media_pipeline_start(&isc->video_dev.entity, &isc->mpipe);
>> +     if (ret)
>> +             goto err_pipeline_start;
>> +
>>        /* Enable stream on the sub device */
>>        ret = v4l2_subdev_call(isc->current_subdev->sd, video, s_stream, 1);
>>        if (ret && ret != -ENOIOCTLCMD) {
>> @@ -384,6 +383,9 @@ static int isc_start_streaming(struct vb2_queue *vq, unsigned int count)
>>        v4l2_subdev_call(isc->current_subdev->sd, video, s_stream, 0);
>>
>>   err_start_stream:
>> +     media_pipeline_stop(&isc->video_dev.entity);
>> +
>> +err_pipeline_start:
>>        spin_lock_irqsave(&isc->dma_queue_lock, flags);
>>        list_for_each_entry(buf, &isc->dma_queue, list)
>>                vb2_buffer_done(&buf->vb.vb2_buf, VB2_BUF_STATE_QUEUED);
>> @@ -420,6 +422,9 @@ static void isc_stop_streaming(struct vb2_queue *vq)
>>        if (ret && ret != -ENOIOCTLCMD)
>>                v4l2_err(&isc->v4l2_dev, "stream off failed in subdev\n");
>>
>> +     /* Stop media pipeline */
>> +     media_pipeline_stop(&isc->video_dev.entity);
>> +
>>        /* Release all active buffers */
>>        spin_lock_irqsave(&isc->dma_queue_lock, flags);
>>        if (unlikely(isc->cur_frm)) {
>> @@ -496,21 +501,56 @@ static int isc_enum_fmt_vid_cap(struct file *file, void *priv,
>>        u32 index = f->index;
>>        u32 i, supported_index;
>>
>> -     if (index < isc->controller_formats_size) {
>> -             f->pixelformat = isc->controller_formats[index].fourcc;
>> -             return 0;
>> +     supported_index = 0;
>> +
>> +     for (i = 0; i < isc->formats_list_size; i++) {
>> +             if (!isc->formats_list[i].sd_support)
>> +                     continue;
> 
> Sorry to ask again about sd_support, but if the ISC formats
> enumeration is not constrained to a specific mbus_code, shouldn't all
> the formats be enumerated regardless if they're supported from the
> sensor or not ?

Yes. this slipped a little. I have to rework a bit the format reporting 
to user space.

> 
>> +             /*
>> +              * If specific mbus_code is requested, provide only
>> +              * supported formats with this mbus code
>> +              */
>> +             if (f->mbus_code && f->mbus_code !=
>> +                 isc->formats_list[i].mbus_code)
> 
> nit: for clarity
>                  if (f->mbus_code &&
>                      f->mbus_code != isc->formats_list[i].mbus_code)
> 
>> +                     continue;
>> +             if (supported_index == index) {
>> +                     f->pixelformat = isc->formats_list[i].fourcc;
>> +                     return 0;
>> +             }
>> +             supported_index++;
>>        }
>>
>> -     index -= isc->controller_formats_size;
>> +     /*
>> +      * If the sensor does not support this mbus_code whatsoever,
>> +      * there is no reason to advertise any of our output formats
>> +      */
>> +     if (supported_index == 0)
>> +             return -EINVAL;
>>
>> +     /*
>> +      * If the sensor uses a format that is not raw, then we cannot
>> +      * convert it to any of the formats that we usually can with a
>> +      * RAW sensor. Thus, do not advertise them.
>> +      */
>> +     if (isc->config.sd_format &&
>> +         !ISC_IS_FORMAT_RAW(isc->config.sd_format->mbus_code))
>> +             return -EINVAL;
>> +
>> +     /*
>> +      * Iterate again through the formats that we can convert to.
>> +      * However, to avoid duplicates, skip the formats that
>> +      * the sensor already supports directly
>> +      */
>> +     index -= supported_index;
>>        supported_index = 0;
>>
>> -     for (i = 0; i < isc->formats_list_size; i++) {
>> -             if (!ISC_IS_FORMAT_RAW(isc->formats_list[i].mbus_code) ||
>> -                 !isc->formats_list[i].sd_support)
>> +     for (i = 0; i < isc->controller_formats_size; i++) {
>> +             /* if this format is already supported by sensor, skip it */
>> +             if (find_format_by_fourcc(isc, isc->controller_formats[i].fourcc))
>>                        continue;
>>                if (supported_index == index) {
>> -                     f->pixelformat = isc->formats_list[i].fourcc;
>> +                     f->pixelformat =
>> +                             isc->controller_formats[i].fourcc;
> 
> I trust this last part to work correctly, as it's not 100% clear to me :)
> 

I think I will remove this and just report all the formats to userspace. 
Let libcamera handle this ;)

>>                        return 0;
>>                }
>>                supported_index++;
>> @@ -581,20 +621,30 @@ static int isc_try_validate_formats(struct isc_device *isc)
>>                break;
>>        default:
>>        /* any other different formats are not supported */
>> +             v4l2_err(&isc->v4l2_dev, "Requested unsupported format.\n");
>>                ret = -EINVAL;
>>        }
>>        v4l2_dbg(1, debug, &isc->v4l2_dev,
>>                 "Format validation, requested rgb=%u, yuv=%u, grey=%u, bayer=%u\n",
>>                 rgb, yuv, grey, bayer);
>>
>> -     /* we cannot output RAW if we do not receive RAW */
>> -     if ((bayer) && !ISC_IS_FORMAT_RAW(isc->try_config.sd_format->mbus_code))
>> +     if ((bayer) &&
> 
> just 'bayer' ?

not sure what you mean ?
Have to check if we can output raw bayer , and we can only do that if we 
receive raw bayer from the sensor.

> 
>> +         !ISC_IS_FORMAT_RAW(isc->try_config.sd_format->mbus_code)) {
>> +             v4l2_err(&isc->v4l2_dev, "Cannot output RAW if we do not receive RAW.\n");
>>                return -EINVAL;
>> +     }
>>
>> -     /* we cannot output GREY if we do not receive RAW/GREY */
>>        if (grey && !ISC_IS_FORMAT_RAW(isc->try_config.sd_format->mbus_code) &&
>> -         !ISC_IS_FORMAT_GREY(isc->try_config.sd_format->mbus_code))
>> +         !ISC_IS_FORMAT_GREY(isc->try_config.sd_format->mbus_code)) {
>> +             v4l2_err(&isc->v4l2_dev, "Cannot output GREY if we do not receive RAW/GREY.\n");
>> +             return -EINVAL;
>> +     }
>> +
>> +     if ((rgb || bayer || yuv) &&
>> +         ISC_IS_FORMAT_GREY(isc->try_config.sd_format->mbus_code)) {
>> +             v4l2_err(&isc->v4l2_dev, "Cannot convert GREY to another format.\n");
>>                return -EINVAL;
>> +     }
>>
>>        return ret;
>>   }
>> @@ -822,7 +872,7 @@ static void isc_try_fse(struct isc_device *isc,
>>         * If we do not know yet which format the subdev is using, we cannot
>>         * do anything.
>>         */
>> -     if (!isc->try_config.sd_format)
>> +     if (!isc->config.sd_format)
>>                return;
>>
>>        fse.code = isc->try_config.sd_format->mbus_code;
>> @@ -843,180 +893,141 @@ static void isc_try_fse(struct isc_device *isc,
>>        }
>>   }
>>
>> -static int isc_try_fmt(struct isc_device *isc, struct v4l2_format *f,
>> -                     u32 *code)
>> +static int isc_try_fmt(struct isc_device *isc, struct v4l2_format *f)
>>   {
>> -     int i;
>> -     struct isc_format *sd_fmt = NULL, *direct_fmt = NULL;
>>        struct v4l2_pix_format *pixfmt = &f->fmt.pix;
>> -     struct v4l2_subdev_pad_config pad_cfg = {};
>> -     struct v4l2_subdev_state pad_state = {
>> -             .pads = &pad_cfg
>> -             };
>> -     struct v4l2_subdev_format format = {
>> -             .which = V4L2_SUBDEV_FORMAT_TRY,
>> -     };
>> -     u32 mbus_code;
>> -     int ret;
>> -     bool rlp_dma_direct_dump = false;
>> +     unsigned int i;
>>
>>        if (f->type != V4L2_BUF_TYPE_VIDEO_CAPTURE)
>>                return -EINVAL;
>>
>> -     /* Step 1: find a RAW format that is supported */
>> -     for (i = 0; i < isc->num_user_formats; i++) {
>> -             if (ISC_IS_FORMAT_RAW(isc->user_formats[i]->mbus_code)) {
>> -                     sd_fmt = isc->user_formats[i];
>> +     isc->try_config.fourcc = isc->user_formats[0]->fourcc;
>> +
>> +     /* find if the format requested is supported */
>> +     for (i = 0; i < isc->controller_formats_size; i++)
>> +             if (isc->controller_formats[i].fourcc == pixfmt->pixelformat) {
>> +                     isc->try_config.fourcc = pixfmt->pixelformat;
>>                        break;
>>                }
>> -     }
>> -     /* Step 2: We can continue with this RAW format, or we can look
>> -      * for better: maybe sensor supports directly what we need.
>> -      */
>> -     direct_fmt = find_format_by_fourcc(isc, pixfmt->pixelformat);
>> -
>> -     /* Step 3: We have both. We decide given the module parameter which
>> -      * one to use.
>> -      */
>> -     if (direct_fmt && sd_fmt && sensor_preferred)
>> -             sd_fmt = direct_fmt;
>> -
>> -     /* Step 4: we do not have RAW but we have a direct format. Use it. */
>> -     if (direct_fmt && !sd_fmt)
>> -             sd_fmt = direct_fmt;
>> -
>> -     /* Step 5: if we are using a direct format, we need to package
>> -      * everything as 8 bit data and just dump it
>> -      */
>> -     if (sd_fmt == direct_fmt)
>> -             rlp_dma_direct_dump = true;
>> -
>> -     /* Step 6: We have no format. This can happen if the userspace
>> -      * requests some weird/invalid format.
>> -      * In this case, default to whatever we have
>> -      */
>> -     if (!sd_fmt && !direct_fmt) {
>> -             sd_fmt = isc->user_formats[isc->num_user_formats - 1];
>> -             v4l2_dbg(1, debug, &isc->v4l2_dev,
>> -                      "Sensor not supporting %.4s, using %.4s\n",
>> -                      (char *)&pixfmt->pixelformat, (char *)&sd_fmt->fourcc);
>> -     }
>> -
>> -     if (!sd_fmt) {
>> -             ret = -EINVAL;
>> -             goto isc_try_fmt_err;
>> -     }
>> -
>> -     /* Step 7: Print out what we decided for debugging */
>> -     v4l2_dbg(1, debug, &isc->v4l2_dev,
>> -              "Preferring to have sensor using format %.4s\n",
>> -              (char *)&sd_fmt->fourcc);
>> -
>> -     /* Step 8: at this moment we decided which format the subdev will use */
>> -     isc->try_config.sd_format = sd_fmt;
>> -
>> -     /* Limit to Atmel ISC hardware capabilities */
>> -     if (pixfmt->width > isc->max_width)
>> -             pixfmt->width = isc->max_width;
>> -     if (pixfmt->height > isc->max_height)
>> -             pixfmt->height = isc->max_height;
>> -
>> -     /*
>> -      * The mbus format is the one the subdev outputs.
>> -      * The pixels will be transferred in this format Sensor -> ISC
>> -      */
>> -     mbus_code = sd_fmt->mbus_code;
>> -
>> -     /*
>> -      * Validate formats. If the required format is not OK, default to raw.
>> -      */
>> -
>> -     isc->try_config.fourcc = pixfmt->pixelformat;
>> -
>> -     if (isc_try_validate_formats(isc)) {
>> -             pixfmt->pixelformat = isc->try_config.fourcc = sd_fmt->fourcc;
>> -             /* Re-try to validate the new format */
>> -             ret = isc_try_validate_formats(isc);
>> -             if (ret)
>> -                     goto isc_try_fmt_err;
>> -     }
>> -
>> -     ret = isc_try_configure_rlp_dma(isc, rlp_dma_direct_dump);
>> -     if (ret)
>> -             goto isc_try_fmt_err;
>> -
>> -     ret = isc_try_configure_pipeline(isc);
>> -     if (ret)
>> -             goto isc_try_fmt_err;
>>
>> -     /* Obtain frame sizes if possible to have crop requirements ready */
>> -     isc_try_fse(isc, &pad_state);
>> -
>> -     v4l2_fill_mbus_format(&format.format, pixfmt, mbus_code);
>> -     ret = v4l2_subdev_call(isc->current_subdev->sd, pad, set_fmt,
>> -                            &pad_state, &format);
>> -     if (ret < 0)
>> -             goto isc_try_fmt_subdev_err;
>> +     /* If we did not find the requested format, we will fallback here */
>> +     pixfmt->pixelformat = isc->try_config.fourcc;
>> +     pixfmt->colorspace = V4L2_COLORSPACE_SRGB;
>> +     pixfmt->field = V4L2_FIELD_NONE;
>>
>> -     v4l2_fill_pix_format(pixfmt, &format.format);
>> +     isc_try_configure_rlp_dma(isc, false);
>>
>>        /* Limit to Atmel ISC hardware capabilities */
>> -     if (pixfmt->width > isc->max_width)
>> -             pixfmt->width = isc->max_width;
>> -     if (pixfmt->height > isc->max_height)
>> -             pixfmt->height = isc->max_height;
>> +     v4l_bound_align_image(&pixfmt->width, 16, isc->max_width, 0,
>> +                           &pixfmt->height, 16, isc->max_height, 0, 0);
>>
>>        pixfmt->field = V4L2_FIELD_NONE;
>>        pixfmt->bytesperline = (pixfmt->width * isc->try_config.bpp_v4l2) >> 3;
>>        pixfmt->sizeimage = ((pixfmt->width * isc->try_config.bpp) >> 3) *
>>                             pixfmt->height;
> 
> Seems pixfmt->field is set twice.
> 
> Could you move the assignment of all pixfmt to a single block ?

okay
> 
>>
>> -     if (code)
>> -             *code = mbus_code;
>> +     isc->try_fmt = *f;
>>
>>        return 0;
>> +}
>>
>> -isc_try_fmt_err:
>> -     v4l2_err(&isc->v4l2_dev, "Could not find any possible format for a working pipeline\n");
>> -isc_try_fmt_subdev_err:
>> -     memset(&isc->try_config, 0, sizeof(isc->try_config));
>> +static int isc_set_fmt(struct isc_device *isc, struct v4l2_format *f)
>> +{
>> +     isc_try_fmt(isc, f);
>>
>> -     return ret;
>> +     /* make the try configuration active */
>> +     isc->config = isc->try_config;
>> +     isc->fmt = isc->try_fmt;
>> +
>> +     v4l2_dbg(1, debug, &isc->v4l2_dev, "ISC set_fmt to %.4s @%dx%d\n",
>> +              (char *)&f->fmt.pix.pixelformat,
>> +              f->fmt.pix.width, f->fmt.pix.height);
>> +
>> +     return 0;
>>   }
>>
>> -static int isc_set_fmt(struct isc_device *isc, struct v4l2_format *f)
>> +static int isc_validate(struct isc_device *isc)
>>   {
>> +     int ret;
>> +     int i;
>> +     struct isc_format *sd_fmt = NULL;
>> +     struct v4l2_pix_format *pixfmt = &isc->fmt.fmt.pix;
>>        struct v4l2_subdev_format format = {
>>                .which = V4L2_SUBDEV_FORMAT_ACTIVE,
>> +             .pad = isc->remote_pad,
>> +     };
>> +     struct v4l2_subdev_pad_config pad_cfg = {};
>> +     struct v4l2_subdev_state pad_state = {
>> +             .pads = &pad_cfg,
>>        };
>> -     u32 mbus_code = 0;
>> -     int ret;
>>
>> -     ret = isc_try_fmt(isc, f, &mbus_code);
>> +     /* Get current format from subdev */
>> +     ret = v4l2_subdev_call(isc->current_subdev->sd, pad, get_fmt, NULL,
>> +                            &format);
>>        if (ret)
>>                return ret;
>>
>> -     v4l2_fill_mbus_format(&format.format, &f->fmt.pix, mbus_code);
>> -     ret = v4l2_subdev_call(isc->current_subdev->sd, pad,
>> -                            set_fmt, NULL, &format);
>> -     if (ret < 0)
>> -             return ret;
>> +     /* Identify the subdev's format configuration */
>> +     for (i = 0; i < isc->num_user_formats; i++)
>> +             if (isc->user_formats[i]->mbus_code == format.format.code) {
>> +                     sd_fmt = isc->user_formats[i];
>> +                     break;
>> +             }
>> +
>> +     /* Check if the format is not supported */
>> +     if (!sd_fmt) {
>> +             v4l2_err(&isc->v4l2_dev,
>> +                      "Current subdevice is streaming a media bus code that is not supported 0x%x\n",
>> +                      format.format.code);
>> +             return -EPIPE;
>> +     }
>> +
>> +     /* At this moment we know which format the subdev will use */
>> +     isc->try_config.sd_format = sd_fmt;
>> +
>> +     /* If the sensor is not RAW, we can only do a direct dump */
>> +     if (!ISC_IS_FORMAT_RAW(isc->try_config.sd_format->mbus_code))
>> +             isc_try_configure_rlp_dma(isc, true);
>>
>>        /* Limit to Atmel ISC hardware capabilities */
>> -     if (f->fmt.pix.width > isc->max_width)
>> -             f->fmt.pix.width = isc->max_width;
>> -     if (f->fmt.pix.height > isc->max_height)
>> -             f->fmt.pix.height = isc->max_height;
>> +     v4l_bound_align_image(&format.format.width, 16, isc->max_width, 0,
>> +                           &format.format.height, 16, isc->max_height, 0, 0);
>> +
>> +     /* Check if the frame size is the same. Otherwise we may overflow */
>> +     if (pixfmt->height != format.format.height ||
>> +         pixfmt->width != format.format.width) {
>> +             v4l2_err(&isc->v4l2_dev,
>> +                      "ISC not configured with the proper frame size: %dx%d\n",
>> +                      format.format.width, format.format.height);
>> +             return -EPIPE;
>> +     }
>>
>> -     isc->fmt = *f;
>> +     v4l2_dbg(1, debug, &isc->v4l2_dev,
>> +              "Identified subdev using format %.4s with %dx%d %d bpp\n",
>> +              (char *)&sd_fmt->fourcc, pixfmt->width, pixfmt->height,
>> +              isc->try_config.bpp);
>>
>> +     /* Reset and restart AWB if the subdevice changed the format */
>>        if (isc->try_config.sd_format && isc->config.sd_format &&
>>            isc->try_config.sd_format != isc->config.sd_format) {
>>                isc->ctrls.hist_stat = HIST_INIT;
>>                isc_reset_awb_ctrls(isc);
>>                isc_update_v4l2_ctrls(isc);
>>        }
>> -     /* make the try configuration active */
>> +
>> +     /* Validate formats */
>> +     ret = isc_try_validate_formats(isc);
>> +     if (ret)
>> +             return ret;
>> +
>> +     /* Obtain frame sizes if possible to have crop requirements ready */
>> +     isc_try_fse(isc, &pad_state);
>> +
>> +     /* Configure ISC pipeline for the config */
>> +     ret = isc_try_configure_pipeline(isc);
>> +     if (ret)
>> +             return ret;
>> +
>>        isc->config = isc->try_config;
>>
>>        v4l2_dbg(1, debug, &isc->v4l2_dev, "New ISC configuration in place\n");
>> @@ -1040,7 +1051,7 @@ static int isc_try_fmt_vid_cap(struct file *file, void *priv,
>>   {
>>        struct isc_device *isc = video_drvdata(file);
>>
>> -     return isc_try_fmt(isc, f, NULL);
>> +     return isc_try_fmt(isc, f);
>>   }
>>
>>   static int isc_enum_input(struct file *file, void *priv,
>> @@ -1841,7 +1852,7 @@ static int isc_set_default_fmt(struct isc_device *isc)
>>        };
>>        int ret;
>>
>> -     ret = isc_try_fmt(isc, &f, NULL);
>> +     ret = isc_try_fmt(isc, &f);
>>        if (ret)
>>                return ret;
>>
>> @@ -2015,6 +2026,24 @@ int isc_pipeline_init(struct isc_device *isc)
>>   }
>>   EXPORT_SYMBOL_GPL(isc_pipeline_init);
>>
>> +int isc_link_validate(struct media_link *link)
>> +{
>> +     struct video_device *vdev =
>> +             media_entity_to_video_device(link->sink->entity);
>> +     struct isc_device *isc = video_get_drvdata(vdev);
>> +     int ret;
>> +
>> +     ret = v4l2_subdev_link_validate(link);
>> +     if (ret)
>> +             return ret;
> 
> Doesn't v4l2_subdev_link_validate() call
> v4l2_subdev_link_validate_default() if you don't define a .link_validate()
> pad operation ? v4l2_subdev_link_validate_default() compares format
> and sizes of both ends to the links and want them to be identical,
> something that defeat the purpose of your custom isc_validate() ?

I think so. However if I replace the validate call with my custom one, I 
thought that the old default should be called as well.

Meaning, that maybe my custom validation does certain isc-related 
checks, while the v4l2_subdev_link_validate does exactly what you said.
So, by defining a custom link_validate, do I lose the checks that are 
done by the v4l2_subdev_link_validate ?
That's what I wanted to avoid. Chip in my checks, but keep the v4l2 
standard validation in place.

Does that make sense ?

> Thanks
>    j
> 
>> +
>> +     return isc_validate(isc);
>> +}
>> +
>> +static const struct media_entity_operations isc_entity_operations = {
>> +     .link_validate = isc_link_validate,
>> +};
>> +
> };
>>   int isc_mc_init(struct isc_device *isc, u32 ver)
>>   {
>>        const struct of_device_id *match;
>> @@ -2022,6 +2051,8 @@ int isc_mc_init(struct isc_device *isc, u32 ver)
>>
>>        isc->video_dev.entity.function = MEDIA_ENT_F_IO_V4L;
>>        isc->video_dev.entity.flags = MEDIA_ENT_FL_DEFAULT;
>> +     isc->video_dev.entity.ops = &isc_entity_operations;
>> +
>>        isc->pads[ISC_PAD_SINK].flags = MEDIA_PAD_FL_SINK;
>>
>>        ret = media_entity_pads_init(&isc->video_dev.entity, ISC_PADS_NUM,
>> diff --git a/drivers/media/platform/atmel/atmel-isc-scaler.c b/drivers/media/platform/atmel/atmel-isc-scaler.c
>> index ec95c9665883..93375a61aea6 100644
>> --- a/drivers/media/platform/atmel/atmel-isc-scaler.c
>> +++ b/drivers/media/platform/atmel/atmel-isc-scaler.c
>> @@ -155,6 +155,10 @@ static const struct v4l2_subdev_pad_ops isc_scaler_pad_ops = {
>>        .init_cfg = isc_scaler_init_cfg,
>>   };
>>
>> +static const struct media_entity_operations isc_scaler_entity_ops = {
>> +     .link_validate = v4l2_subdev_link_validate,
>> +};
>> +
>>   static const struct v4l2_subdev_ops xisc_scaler_subdev_ops = {
>>        .pad = &isc_scaler_pad_ops,
>>   };
>> @@ -172,6 +176,7 @@ int isc_scaler_init(struct isc_device *isc)
>>
>>        isc->scaler_sd.flags |= V4L2_SUBDEV_FL_HAS_DEVNODE;
>>        isc->scaler_sd.entity.function = MEDIA_ENT_F_PROC_VIDEO_SCALER;
>> +     isc->scaler_sd.entity.ops = &isc_scaler_entity_ops;
>>        isc->scaler_pads[ISC_SCALER_PAD_SINK].flags = MEDIA_PAD_FL_SINK;
>>        isc->scaler_pads[ISC_SCALER_PAD_SOURCE].flags = MEDIA_PAD_FL_SOURCE;
>>
>> diff --git a/drivers/media/platform/atmel/atmel-isc.h b/drivers/media/platform/atmel/atmel-isc.h
>> index 04ea5e340808..e36cf9d3942a 100644
>> --- a/drivers/media/platform/atmel/atmel-isc.h
>> +++ b/drivers/media/platform/atmel/atmel-isc.h
>> @@ -270,6 +270,7 @@ enum isc_scaler_pads {
>>    * @formats_list_size:       size of formats_list array
>>    * @pads:            media controller pads for isc video entity
>>    * @mdev:            media device that is registered by the isc
>> + * @mpipe:           media device pipeline used by the isc
>>    * @remote_pad:              remote pad on the connected subdevice
>>    * @scaler_sd:               subdevice for the scaler that isc registers
>>    * @scaler_pads:     media controller pads for the scaler subdevice
>> @@ -295,6 +296,7 @@ struct isc_device {
>>        struct completion       comp;
>>
>>        struct v4l2_format      fmt;
>> +     struct v4l2_format      try_fmt;
>>        struct isc_format       **user_formats;
>>        unsigned int            num_user_formats;
>>
>> @@ -366,6 +368,7 @@ struct isc_device {
>>        struct {
>>                struct media_pad                pads[ISC_PADS_NUM];
>>                struct media_device             mdev;
>> +             struct media_pipeline           mpipe;
>>
>>                u32                             remote_pad;
>>        };
>> --
>> 2.25.1
>>
Jacopo Mondi Feb. 11, 2022, 11:59 a.m. UTC | #3
Hi Eugen,

On Fri, Feb 11, 2022 at 10:38:56AM +0000, Eugen.Hristev@microchip.com wrote:
> On 2/10/22 8:43 PM, Jacopo Mondi wrote:
> > Hi Eugen
> >
> > On Fri, Jan 21, 2022 at 03:14:12PM +0200, Eugen Hristev wrote:
> >> As a top MC video driver, the atmel-isc should not propagate the format to the
> >> subdevice.
> >> It should rather check at start_streaming() time if the subdev is properly
> >> configured with a compatible format.
> >> Removed the whole format finding logic, and reworked the format verification
> >> at start_streaming time, such that the ISC will return an error if the subdevice
> >> is not properly configured. To achieve this, media_pipeline_start
> >> is called and a link_validate callback is created to check the formats.
> >> With this being done, the module parameter 'sensor_preferred' makes no sense
> >> anymore. The ISC should not decide which format the sensor is using. The
> >> ISC should only cope with the situation and inform userspace if the streaming
> >> is possible in the current configuration.
> >
> > This sounds right!
> >
> >> The redesign of the format propagation has also risen the question of the
> >> enumfmt callback. If enumfmt is called with an mbus_code, the enumfmt handler
> >> should only return the formats that are supported for this mbus_code.
> >> To make it more easy to understand the formats, changed the report order
> >> to report first the native formats, and after that the formats that the ISC
> >> can convert to.
> >>
> >> Signed-off-by: Eugen Hristev <eugen.hristev@microchip.com>
> >> ---
> >> Changes in v4:
> >> - moved validation code into link_validate and used media_pipeline_start
> >> - merged this patch with the enum_fmt patch which was previously in v3 of
> >> the series
> >>
> >> Changes in v3:
> >> - clamp to maximum resolution once the frame size from the subdev is found
> >>
> >>   drivers/media/platform/atmel/atmel-isc-base.c | 335 ++++++++++--------
> >>   .../media/platform/atmel/atmel-isc-scaler.c   |   5 +
> >>   drivers/media/platform/atmel/atmel-isc.h      |   3 +
> >>   3 files changed, 191 insertions(+), 152 deletions(-)
> >>
> >> diff --git a/drivers/media/platform/atmel/atmel-isc-base.c b/drivers/media/platform/atmel/atmel-isc-base.c
> >> index f7a88399bd54..31c79313aadc 100644
> >> --- a/drivers/media/platform/atmel/atmel-isc-base.c
> >> +++ b/drivers/media/platform/atmel/atmel-isc-base.c
> >> @@ -36,11 +36,6 @@ static unsigned int debug;
> >>   module_param(debug, int, 0644);
> >>   MODULE_PARM_DESC(debug, "debug level (0-2)");
> >>
> >> -static unsigned int sensor_preferred = 1;
> >> -module_param(sensor_preferred, uint, 0644);
> >> -MODULE_PARM_DESC(sensor_preferred,
> >> -              "Sensor is preferred to output the specified format (1-on 0-off), default 1");
> >> -
> >>   #define ISC_IS_FORMAT_RAW(mbus_code) \
> >>        (((mbus_code) & 0xf000) == 0x3000)
> >>
> >> @@ -337,6 +332,10 @@ static int isc_start_streaming(struct vb2_queue *vq, unsigned int count)
> >>        unsigned long flags;
> >>        int ret;
> >>
> >> +     ret = media_pipeline_start(&isc->video_dev.entity, &isc->mpipe);
> >> +     if (ret)
> >> +             goto err_pipeline_start;
> >> +
> >>        /* Enable stream on the sub device */
> >>        ret = v4l2_subdev_call(isc->current_subdev->sd, video, s_stream, 1);
> >>        if (ret && ret != -ENOIOCTLCMD) {
> >> @@ -384,6 +383,9 @@ static int isc_start_streaming(struct vb2_queue *vq, unsigned int count)
> >>        v4l2_subdev_call(isc->current_subdev->sd, video, s_stream, 0);
> >>
> >>   err_start_stream:
> >> +     media_pipeline_stop(&isc->video_dev.entity);
> >> +
> >> +err_pipeline_start:
> >>        spin_lock_irqsave(&isc->dma_queue_lock, flags);
> >>        list_for_each_entry(buf, &isc->dma_queue, list)
> >>                vb2_buffer_done(&buf->vb.vb2_buf, VB2_BUF_STATE_QUEUED);
> >> @@ -420,6 +422,9 @@ static void isc_stop_streaming(struct vb2_queue *vq)
> >>        if (ret && ret != -ENOIOCTLCMD)
> >>                v4l2_err(&isc->v4l2_dev, "stream off failed in subdev\n");
> >>
> >> +     /* Stop media pipeline */
> >> +     media_pipeline_stop(&isc->video_dev.entity);
> >> +
> >>        /* Release all active buffers */
> >>        spin_lock_irqsave(&isc->dma_queue_lock, flags);
> >>        if (unlikely(isc->cur_frm)) {
> >> @@ -496,21 +501,56 @@ static int isc_enum_fmt_vid_cap(struct file *file, void *priv,
> >>        u32 index = f->index;
> >>        u32 i, supported_index;
> >>
> >> -     if (index < isc->controller_formats_size) {
> >> -             f->pixelformat = isc->controller_formats[index].fourcc;
> >> -             return 0;
> >> +     supported_index = 0;
> >> +
> >> +     for (i = 0; i < isc->formats_list_size; i++) {
> >> +             if (!isc->formats_list[i].sd_support)
> >> +                     continue;
> >
> > Sorry to ask again about sd_support, but if the ISC formats
> > enumeration is not constrained to a specific mbus_code, shouldn't all
> > the formats be enumerated regardless if they're supported from the
> > sensor or not ?
>
> Yes. this slipped a little. I have to rework a bit the format reporting
> to user space.
>
> >
> >> +             /*
> >> +              * If specific mbus_code is requested, provide only
> >> +              * supported formats with this mbus code
> >> +              */
> >> +             if (f->mbus_code && f->mbus_code !=
> >> +                 isc->formats_list[i].mbus_code)
> >
> > nit: for clarity
> >                  if (f->mbus_code &&
> >                      f->mbus_code != isc->formats_list[i].mbus_code)
> >
> >> +                     continue;
> >> +             if (supported_index == index) {
> >> +                     f->pixelformat = isc->formats_list[i].fourcc;
> >> +                     return 0;
> >> +             }
> >> +             supported_index++;
> >>        }
> >>
> >> -     index -= isc->controller_formats_size;
> >> +     /*
> >> +      * If the sensor does not support this mbus_code whatsoever,
> >> +      * there is no reason to advertise any of our output formats
> >> +      */
> >> +     if (supported_index == 0)
> >> +             return -EINVAL;
> >>
> >> +     /*
> >> +      * If the sensor uses a format that is not raw, then we cannot
> >> +      * convert it to any of the formats that we usually can with a
> >> +      * RAW sensor. Thus, do not advertise them.
> >> +      */
> >> +     if (isc->config.sd_format &&
> >> +         !ISC_IS_FORMAT_RAW(isc->config.sd_format->mbus_code))
> >> +             return -EINVAL;
> >> +
> >> +     /*
> >> +      * Iterate again through the formats that we can convert to.
> >> +      * However, to avoid duplicates, skip the formats that
> >> +      * the sensor already supports directly
> >> +      */
> >> +     index -= supported_index;
> >>        supported_index = 0;
> >>
> >> -     for (i = 0; i < isc->formats_list_size; i++) {
> >> -             if (!ISC_IS_FORMAT_RAW(isc->formats_list[i].mbus_code) ||
> >> -                 !isc->formats_list[i].sd_support)
> >> +     for (i = 0; i < isc->controller_formats_size; i++) {
> >> +             /* if this format is already supported by sensor, skip it */
> >> +             if (find_format_by_fourcc(isc, isc->controller_formats[i].fourcc))
> >>                        continue;
> >>                if (supported_index == index) {
> >> -                     f->pixelformat = isc->formats_list[i].fourcc;
> >> +                     f->pixelformat =
> >> +                             isc->controller_formats[i].fourcc;
> >
> > I trust this last part to work correctly, as it's not 100% clear to me :)
> >
>
> I think I will remove this and just report all the formats to userspace.
> Let libcamera handle this ;)
>

I think so, the driver will be greatly simplified with this change.

> >>                        return 0;
> >>                }
> >>                supported_index++;
> >> @@ -581,20 +621,30 @@ static int isc_try_validate_formats(struct isc_device *isc)
> >>                break;
> >>        default:
> >>        /* any other different formats are not supported */
> >> +             v4l2_err(&isc->v4l2_dev, "Requested unsupported format.\n");
> >>                ret = -EINVAL;
> >>        }
> >>        v4l2_dbg(1, debug, &isc->v4l2_dev,
> >>                 "Format validation, requested rgb=%u, yuv=%u, grey=%u, bayer=%u\n",
> >>                 rgb, yuv, grey, bayer);
> >>
> >> -     /* we cannot output RAW if we do not receive RAW */
> >> -     if ((bayer) && !ISC_IS_FORMAT_RAW(isc->try_config.sd_format->mbus_code))
> >> +     if ((bayer) &&
> >
> > just 'bayer' ?
>
> not sure what you mean ?
> Have to check if we can output raw bayer , and we can only do that if we
> receive raw bayer from the sensor.
>

I just meant that you could remove () from (bayer) ?

Sorry for not being clear :)

> >
> >> +         !ISC_IS_FORMAT_RAW(isc->try_config.sd_format->mbus_code)) {
> >> +             v4l2_err(&isc->v4l2_dev, "Cannot output RAW if we do not receive RAW.\n");
> >>                return -EINVAL;
> >> +     }
> >>
> >> -     /* we cannot output GREY if we do not receive RAW/GREY */
> >>        if (grey && !ISC_IS_FORMAT_RAW(isc->try_config.sd_format->mbus_code) &&
> >> -         !ISC_IS_FORMAT_GREY(isc->try_config.sd_format->mbus_code))
> >> +         !ISC_IS_FORMAT_GREY(isc->try_config.sd_format->mbus_code)) {
> >> +             v4l2_err(&isc->v4l2_dev, "Cannot output GREY if we do not receive RAW/GREY.\n");
> >> +             return -EINVAL;
> >> +     }
> >> +
> >> +     if ((rgb || bayer || yuv) &&
> >> +         ISC_IS_FORMAT_GREY(isc->try_config.sd_format->mbus_code)) {
> >> +             v4l2_err(&isc->v4l2_dev, "Cannot convert GREY to another format.\n");
> >>                return -EINVAL;
> >> +     }
> >>
> >>        return ret;
> >>   }
> >> @@ -822,7 +872,7 @@ static void isc_try_fse(struct isc_device *isc,
> >>         * If we do not know yet which format the subdev is using, we cannot
> >>         * do anything.
> >>         */
> >> -     if (!isc->try_config.sd_format)
> >> +     if (!isc->config.sd_format)
> >>                return;
> >>
> >>        fse.code = isc->try_config.sd_format->mbus_code;
> >> @@ -843,180 +893,141 @@ static void isc_try_fse(struct isc_device *isc,
> >>        }
> >>   }
> >>
> >> -static int isc_try_fmt(struct isc_device *isc, struct v4l2_format *f,
> >> -                     u32 *code)
> >> +static int isc_try_fmt(struct isc_device *isc, struct v4l2_format *f)
> >>   {
> >> -     int i;
> >> -     struct isc_format *sd_fmt = NULL, *direct_fmt = NULL;
> >>        struct v4l2_pix_format *pixfmt = &f->fmt.pix;
> >> -     struct v4l2_subdev_pad_config pad_cfg = {};
> >> -     struct v4l2_subdev_state pad_state = {
> >> -             .pads = &pad_cfg
> >> -             };
> >> -     struct v4l2_subdev_format format = {
> >> -             .which = V4L2_SUBDEV_FORMAT_TRY,
> >> -     };
> >> -     u32 mbus_code;
> >> -     int ret;
> >> -     bool rlp_dma_direct_dump = false;
> >> +     unsigned int i;
> >>
> >>        if (f->type != V4L2_BUF_TYPE_VIDEO_CAPTURE)
> >>                return -EINVAL;
> >>
> >> -     /* Step 1: find a RAW format that is supported */
> >> -     for (i = 0; i < isc->num_user_formats; i++) {
> >> -             if (ISC_IS_FORMAT_RAW(isc->user_formats[i]->mbus_code)) {
> >> -                     sd_fmt = isc->user_formats[i];
> >> +     isc->try_config.fourcc = isc->user_formats[0]->fourcc;
> >> +
> >> +     /* find if the format requested is supported */
> >> +     for (i = 0; i < isc->controller_formats_size; i++)
> >> +             if (isc->controller_formats[i].fourcc == pixfmt->pixelformat) {
> >> +                     isc->try_config.fourcc = pixfmt->pixelformat;
> >>                        break;
> >>                }
> >> -     }
> >> -     /* Step 2: We can continue with this RAW format, or we can look
> >> -      * for better: maybe sensor supports directly what we need.
> >> -      */
> >> -     direct_fmt = find_format_by_fourcc(isc, pixfmt->pixelformat);
> >> -
> >> -     /* Step 3: We have both. We decide given the module parameter which
> >> -      * one to use.
> >> -      */
> >> -     if (direct_fmt && sd_fmt && sensor_preferred)
> >> -             sd_fmt = direct_fmt;
> >> -
> >> -     /* Step 4: we do not have RAW but we have a direct format. Use it. */
> >> -     if (direct_fmt && !sd_fmt)
> >> -             sd_fmt = direct_fmt;
> >> -
> >> -     /* Step 5: if we are using a direct format, we need to package
> >> -      * everything as 8 bit data and just dump it
> >> -      */
> >> -     if (sd_fmt == direct_fmt)
> >> -             rlp_dma_direct_dump = true;
> >> -
> >> -     /* Step 6: We have no format. This can happen if the userspace
> >> -      * requests some weird/invalid format.
> >> -      * In this case, default to whatever we have
> >> -      */
> >> -     if (!sd_fmt && !direct_fmt) {
> >> -             sd_fmt = isc->user_formats[isc->num_user_formats - 1];
> >> -             v4l2_dbg(1, debug, &isc->v4l2_dev,
> >> -                      "Sensor not supporting %.4s, using %.4s\n",
> >> -                      (char *)&pixfmt->pixelformat, (char *)&sd_fmt->fourcc);
> >> -     }
> >> -
> >> -     if (!sd_fmt) {
> >> -             ret = -EINVAL;
> >> -             goto isc_try_fmt_err;
> >> -     }
> >> -
> >> -     /* Step 7: Print out what we decided for debugging */
> >> -     v4l2_dbg(1, debug, &isc->v4l2_dev,
> >> -              "Preferring to have sensor using format %.4s\n",
> >> -              (char *)&sd_fmt->fourcc);
> >> -
> >> -     /* Step 8: at this moment we decided which format the subdev will use */
> >> -     isc->try_config.sd_format = sd_fmt;
> >> -
> >> -     /* Limit to Atmel ISC hardware capabilities */
> >> -     if (pixfmt->width > isc->max_width)
> >> -             pixfmt->width = isc->max_width;
> >> -     if (pixfmt->height > isc->max_height)
> >> -             pixfmt->height = isc->max_height;
> >> -
> >> -     /*
> >> -      * The mbus format is the one the subdev outputs.
> >> -      * The pixels will be transferred in this format Sensor -> ISC
> >> -      */
> >> -     mbus_code = sd_fmt->mbus_code;
> >> -
> >> -     /*
> >> -      * Validate formats. If the required format is not OK, default to raw.
> >> -      */
> >> -
> >> -     isc->try_config.fourcc = pixfmt->pixelformat;
> >> -
> >> -     if (isc_try_validate_formats(isc)) {
> >> -             pixfmt->pixelformat = isc->try_config.fourcc = sd_fmt->fourcc;
> >> -             /* Re-try to validate the new format */
> >> -             ret = isc_try_validate_formats(isc);
> >> -             if (ret)
> >> -                     goto isc_try_fmt_err;
> >> -     }
> >> -
> >> -     ret = isc_try_configure_rlp_dma(isc, rlp_dma_direct_dump);
> >> -     if (ret)
> >> -             goto isc_try_fmt_err;
> >> -
> >> -     ret = isc_try_configure_pipeline(isc);
> >> -     if (ret)
> >> -             goto isc_try_fmt_err;
> >>
> >> -     /* Obtain frame sizes if possible to have crop requirements ready */
> >> -     isc_try_fse(isc, &pad_state);
> >> -
> >> -     v4l2_fill_mbus_format(&format.format, pixfmt, mbus_code);
> >> -     ret = v4l2_subdev_call(isc->current_subdev->sd, pad, set_fmt,
> >> -                            &pad_state, &format);
> >> -     if (ret < 0)
> >> -             goto isc_try_fmt_subdev_err;
> >> +     /* If we did not find the requested format, we will fallback here */
> >> +     pixfmt->pixelformat = isc->try_config.fourcc;
> >> +     pixfmt->colorspace = V4L2_COLORSPACE_SRGB;
> >> +     pixfmt->field = V4L2_FIELD_NONE;
> >>
> >> -     v4l2_fill_pix_format(pixfmt, &format.format);
> >> +     isc_try_configure_rlp_dma(isc, false);
> >>
> >>        /* Limit to Atmel ISC hardware capabilities */
> >> -     if (pixfmt->width > isc->max_width)
> >> -             pixfmt->width = isc->max_width;
> >> -     if (pixfmt->height > isc->max_height)
> >> -             pixfmt->height = isc->max_height;
> >> +     v4l_bound_align_image(&pixfmt->width, 16, isc->max_width, 0,
> >> +                           &pixfmt->height, 16, isc->max_height, 0, 0);
> >>
> >>        pixfmt->field = V4L2_FIELD_NONE;
> >>        pixfmt->bytesperline = (pixfmt->width * isc->try_config.bpp_v4l2) >> 3;
> >>        pixfmt->sizeimage = ((pixfmt->width * isc->try_config.bpp) >> 3) *
> >>                             pixfmt->height;
> >
> > Seems pixfmt->field is set twice.
> >
> > Could you move the assignment of all pixfmt to a single block ?
>
> okay
> >
> >>
> >> -     if (code)
> >> -             *code = mbus_code;
> >> +     isc->try_fmt = *f;
> >>
> >>        return 0;
> >> +}
> >>
> >> -isc_try_fmt_err:
> >> -     v4l2_err(&isc->v4l2_dev, "Could not find any possible format for a working pipeline\n");
> >> -isc_try_fmt_subdev_err:
> >> -     memset(&isc->try_config, 0, sizeof(isc->try_config));
> >> +static int isc_set_fmt(struct isc_device *isc, struct v4l2_format *f)
> >> +{
> >> +     isc_try_fmt(isc, f);
> >>
> >> -     return ret;
> >> +     /* make the try configuration active */
> >> +     isc->config = isc->try_config;
> >> +     isc->fmt = isc->try_fmt;
> >> +
> >> +     v4l2_dbg(1, debug, &isc->v4l2_dev, "ISC set_fmt to %.4s @%dx%d\n",
> >> +              (char *)&f->fmt.pix.pixelformat,
> >> +              f->fmt.pix.width, f->fmt.pix.height);
> >> +
> >> +     return 0;
> >>   }
> >>
> >> -static int isc_set_fmt(struct isc_device *isc, struct v4l2_format *f)
> >> +static int isc_validate(struct isc_device *isc)
> >>   {
> >> +     int ret;
> >> +     int i;
> >> +     struct isc_format *sd_fmt = NULL;
> >> +     struct v4l2_pix_format *pixfmt = &isc->fmt.fmt.pix;
> >>        struct v4l2_subdev_format format = {
> >>                .which = V4L2_SUBDEV_FORMAT_ACTIVE,
> >> +             .pad = isc->remote_pad,
> >> +     };
> >> +     struct v4l2_subdev_pad_config pad_cfg = {};
> >> +     struct v4l2_subdev_state pad_state = {
> >> +             .pads = &pad_cfg,
> >>        };
> >> -     u32 mbus_code = 0;
> >> -     int ret;
> >>
> >> -     ret = isc_try_fmt(isc, f, &mbus_code);
> >> +     /* Get current format from subdev */
> >> +     ret = v4l2_subdev_call(isc->current_subdev->sd, pad, get_fmt, NULL,
> >> +                            &format);
> >>        if (ret)
> >>                return ret;
> >>
> >> -     v4l2_fill_mbus_format(&format.format, &f->fmt.pix, mbus_code);
> >> -     ret = v4l2_subdev_call(isc->current_subdev->sd, pad,
> >> -                            set_fmt, NULL, &format);
> >> -     if (ret < 0)
> >> -             return ret;
> >> +     /* Identify the subdev's format configuration */
> >> +     for (i = 0; i < isc->num_user_formats; i++)
> >> +             if (isc->user_formats[i]->mbus_code == format.format.code) {
> >> +                     sd_fmt = isc->user_formats[i];
> >> +                     break;
> >> +             }
> >> +
> >> +     /* Check if the format is not supported */
> >> +     if (!sd_fmt) {
> >> +             v4l2_err(&isc->v4l2_dev,
> >> +                      "Current subdevice is streaming a media bus code that is not supported 0x%x\n",
> >> +                      format.format.code);
> >> +             return -EPIPE;
> >> +     }
> >> +
> >> +     /* At this moment we know which format the subdev will use */
> >> +     isc->try_config.sd_format = sd_fmt;
> >> +
> >> +     /* If the sensor is not RAW, we can only do a direct dump */
> >> +     if (!ISC_IS_FORMAT_RAW(isc->try_config.sd_format->mbus_code))
> >> +             isc_try_configure_rlp_dma(isc, true);
> >>
> >>        /* Limit to Atmel ISC hardware capabilities */
> >> -     if (f->fmt.pix.width > isc->max_width)
> >> -             f->fmt.pix.width = isc->max_width;
> >> -     if (f->fmt.pix.height > isc->max_height)
> >> -             f->fmt.pix.height = isc->max_height;
> >> +     v4l_bound_align_image(&format.format.width, 16, isc->max_width, 0,
> >> +                           &format.format.height, 16, isc->max_height, 0, 0);
> >> +
> >> +     /* Check if the frame size is the same. Otherwise we may overflow */
> >> +     if (pixfmt->height != format.format.height ||
> >> +         pixfmt->width != format.format.width) {
> >> +             v4l2_err(&isc->v4l2_dev,
> >> +                      "ISC not configured with the proper frame size: %dx%d\n",
> >> +                      format.format.width, format.format.height);
> >> +             return -EPIPE;
> >> +     }
> >>
> >> -     isc->fmt = *f;
> >> +     v4l2_dbg(1, debug, &isc->v4l2_dev,
> >> +              "Identified subdev using format %.4s with %dx%d %d bpp\n",
> >> +              (char *)&sd_fmt->fourcc, pixfmt->width, pixfmt->height,
> >> +              isc->try_config.bpp);
> >>
> >> +     /* Reset and restart AWB if the subdevice changed the format */
> >>        if (isc->try_config.sd_format && isc->config.sd_format &&
> >>            isc->try_config.sd_format != isc->config.sd_format) {
> >>                isc->ctrls.hist_stat = HIST_INIT;
> >>                isc_reset_awb_ctrls(isc);
> >>                isc_update_v4l2_ctrls(isc);
> >>        }
> >> -     /* make the try configuration active */
> >> +
> >> +     /* Validate formats */
> >> +     ret = isc_try_validate_formats(isc);
> >> +     if (ret)
> >> +             return ret;
> >> +
> >> +     /* Obtain frame sizes if possible to have crop requirements ready */
> >> +     isc_try_fse(isc, &pad_state);
> >> +
> >> +     /* Configure ISC pipeline for the config */
> >> +     ret = isc_try_configure_pipeline(isc);
> >> +     if (ret)
> >> +             return ret;
> >> +
> >>        isc->config = isc->try_config;
> >>
> >>        v4l2_dbg(1, debug, &isc->v4l2_dev, "New ISC configuration in place\n");
> >> @@ -1040,7 +1051,7 @@ static int isc_try_fmt_vid_cap(struct file *file, void *priv,
> >>   {
> >>        struct isc_device *isc = video_drvdata(file);
> >>
> >> -     return isc_try_fmt(isc, f, NULL);
> >> +     return isc_try_fmt(isc, f);
> >>   }
> >>
> >>   static int isc_enum_input(struct file *file, void *priv,
> >> @@ -1841,7 +1852,7 @@ static int isc_set_default_fmt(struct isc_device *isc)
> >>        };
> >>        int ret;
> >>
> >> -     ret = isc_try_fmt(isc, &f, NULL);
> >> +     ret = isc_try_fmt(isc, &f);
> >>        if (ret)
> >>                return ret;
> >>
> >> @@ -2015,6 +2026,24 @@ int isc_pipeline_init(struct isc_device *isc)
> >>   }
> >>   EXPORT_SYMBOL_GPL(isc_pipeline_init);
> >>
> >> +int isc_link_validate(struct media_link *link)
> >> +{
> >> +     struct video_device *vdev =
> >> +             media_entity_to_video_device(link->sink->entity);
> >> +     struct isc_device *isc = video_get_drvdata(vdev);
> >> +     int ret;
> >> +
> >> +     ret = v4l2_subdev_link_validate(link);
> >> +     if (ret)
> >> +             return ret;
> >
> > Doesn't v4l2_subdev_link_validate() call
> > v4l2_subdev_link_validate_default() if you don't define a .link_validate()
> > pad operation ? v4l2_subdev_link_validate_default() compares format
> > and sizes of both ends to the links and want them to be identical,
> > something that defeat the purpose of your custom isc_validate() ?
>
> I think so. However if I replace the validate call with my custom one, I
> thought that the old default should be called as well.
>

I was actually suggesting to remove the call to
v4l2_subdev_link_validate() completely as I thought you were
performing the same checks in your custom validate. If you're not
please ignore this comment, and even if you are my comment is wrong,
as I should have suggested you to remove the duplicated code and let
the framework do that :)


> Meaning, that maybe my custom validation does certain isc-related
> checks, while the v4l2_subdev_link_validate does exactly what you said.
> So, by defining a custom link_validate, do I lose the checks that are
> done by the v4l2_subdev_link_validate ?
> That's what I wanted to avoid. Chip in my checks, but keep the v4l2
> standard validation in place.
>
> Does that make sense ?

Absolutely, sorry for bothering and if the pipeline validation works
please go ahead with what you have!

Thanks
  j

>
> > Thanks
> >    j
> >
> >> +
> >> +     return isc_validate(isc);
> >> +}
> >> +
> >> +static const struct media_entity_operations isc_entity_operations = {
> >> +     .link_validate = isc_link_validate,
> >> +};
> >> +
> > };
> >>   int isc_mc_init(struct isc_device *isc, u32 ver)
> >>   {
> >>        const struct of_device_id *match;
> >> @@ -2022,6 +2051,8 @@ int isc_mc_init(struct isc_device *isc, u32 ver)
> >>
> >>        isc->video_dev.entity.function = MEDIA_ENT_F_IO_V4L;
> >>        isc->video_dev.entity.flags = MEDIA_ENT_FL_DEFAULT;
> >> +     isc->video_dev.entity.ops = &isc_entity_operations;
> >> +
> >>        isc->pads[ISC_PAD_SINK].flags = MEDIA_PAD_FL_SINK;
> >>
> >>        ret = media_entity_pads_init(&isc->video_dev.entity, ISC_PADS_NUM,
> >> diff --git a/drivers/media/platform/atmel/atmel-isc-scaler.c b/drivers/media/platform/atmel/atmel-isc-scaler.c
> >> index ec95c9665883..93375a61aea6 100644
> >> --- a/drivers/media/platform/atmel/atmel-isc-scaler.c
> >> +++ b/drivers/media/platform/atmel/atmel-isc-scaler.c
> >> @@ -155,6 +155,10 @@ static const struct v4l2_subdev_pad_ops isc_scaler_pad_ops = {
> >>        .init_cfg = isc_scaler_init_cfg,
> >>   };
> >>
> >> +static const struct media_entity_operations isc_scaler_entity_ops = {
> >> +     .link_validate = v4l2_subdev_link_validate,
> >> +};
> >> +
> >>   static const struct v4l2_subdev_ops xisc_scaler_subdev_ops = {
> >>        .pad = &isc_scaler_pad_ops,
> >>   };
> >> @@ -172,6 +176,7 @@ int isc_scaler_init(struct isc_device *isc)
> >>
> >>        isc->scaler_sd.flags |= V4L2_SUBDEV_FL_HAS_DEVNODE;
> >>        isc->scaler_sd.entity.function = MEDIA_ENT_F_PROC_VIDEO_SCALER;
> >> +     isc->scaler_sd.entity.ops = &isc_scaler_entity_ops;
> >>        isc->scaler_pads[ISC_SCALER_PAD_SINK].flags = MEDIA_PAD_FL_SINK;
> >>        isc->scaler_pads[ISC_SCALER_PAD_SOURCE].flags = MEDIA_PAD_FL_SOURCE;
> >>
> >> diff --git a/drivers/media/platform/atmel/atmel-isc.h b/drivers/media/platform/atmel/atmel-isc.h
> >> index 04ea5e340808..e36cf9d3942a 100644
> >> --- a/drivers/media/platform/atmel/atmel-isc.h
> >> +++ b/drivers/media/platform/atmel/atmel-isc.h
> >> @@ -270,6 +270,7 @@ enum isc_scaler_pads {
> >>    * @formats_list_size:       size of formats_list array
> >>    * @pads:            media controller pads for isc video entity
> >>    * @mdev:            media device that is registered by the isc
> >> + * @mpipe:           media device pipeline used by the isc
> >>    * @remote_pad:              remote pad on the connected subdevice
> >>    * @scaler_sd:               subdevice for the scaler that isc registers
> >>    * @scaler_pads:     media controller pads for the scaler subdevice
> >> @@ -295,6 +296,7 @@ struct isc_device {
> >>        struct completion       comp;
> >>
> >>        struct v4l2_format      fmt;
> >> +     struct v4l2_format      try_fmt;
> >>        struct isc_format       **user_formats;
> >>        unsigned int            num_user_formats;
> >>
> >> @@ -366,6 +368,7 @@ struct isc_device {
> >>        struct {
> >>                struct media_pad                pads[ISC_PADS_NUM];
> >>                struct media_device             mdev;
> >> +             struct media_pipeline           mpipe;
> >>
> >>                u32                             remote_pad;
> >>        };
> >> --
> >> 2.25.1
> >>
>
diff mbox series

Patch

diff --git a/drivers/media/platform/atmel/atmel-isc-base.c b/drivers/media/platform/atmel/atmel-isc-base.c
index f7a88399bd54..31c79313aadc 100644
--- a/drivers/media/platform/atmel/atmel-isc-base.c
+++ b/drivers/media/platform/atmel/atmel-isc-base.c
@@ -36,11 +36,6 @@  static unsigned int debug;
 module_param(debug, int, 0644);
 MODULE_PARM_DESC(debug, "debug level (0-2)");
 
-static unsigned int sensor_preferred = 1;
-module_param(sensor_preferred, uint, 0644);
-MODULE_PARM_DESC(sensor_preferred,
-		 "Sensor is preferred to output the specified format (1-on 0-off), default 1");
-
 #define ISC_IS_FORMAT_RAW(mbus_code) \
 	(((mbus_code) & 0xf000) == 0x3000)
 
@@ -337,6 +332,10 @@  static int isc_start_streaming(struct vb2_queue *vq, unsigned int count)
 	unsigned long flags;
 	int ret;
 
+	ret = media_pipeline_start(&isc->video_dev.entity, &isc->mpipe);
+	if (ret)
+		goto err_pipeline_start;
+
 	/* Enable stream on the sub device */
 	ret = v4l2_subdev_call(isc->current_subdev->sd, video, s_stream, 1);
 	if (ret && ret != -ENOIOCTLCMD) {
@@ -384,6 +383,9 @@  static int isc_start_streaming(struct vb2_queue *vq, unsigned int count)
 	v4l2_subdev_call(isc->current_subdev->sd, video, s_stream, 0);
 
 err_start_stream:
+	media_pipeline_stop(&isc->video_dev.entity);
+
+err_pipeline_start:
 	spin_lock_irqsave(&isc->dma_queue_lock, flags);
 	list_for_each_entry(buf, &isc->dma_queue, list)
 		vb2_buffer_done(&buf->vb.vb2_buf, VB2_BUF_STATE_QUEUED);
@@ -420,6 +422,9 @@  static void isc_stop_streaming(struct vb2_queue *vq)
 	if (ret && ret != -ENOIOCTLCMD)
 		v4l2_err(&isc->v4l2_dev, "stream off failed in subdev\n");
 
+	/* Stop media pipeline */
+	media_pipeline_stop(&isc->video_dev.entity);
+
 	/* Release all active buffers */
 	spin_lock_irqsave(&isc->dma_queue_lock, flags);
 	if (unlikely(isc->cur_frm)) {
@@ -496,21 +501,56 @@  static int isc_enum_fmt_vid_cap(struct file *file, void *priv,
 	u32 index = f->index;
 	u32 i, supported_index;
 
-	if (index < isc->controller_formats_size) {
-		f->pixelformat = isc->controller_formats[index].fourcc;
-		return 0;
+	supported_index = 0;
+
+	for (i = 0; i < isc->formats_list_size; i++) {
+		if (!isc->formats_list[i].sd_support)
+			continue;
+		/*
+		 * If specific mbus_code is requested, provide only
+		 * supported formats with this mbus code
+		 */
+		if (f->mbus_code && f->mbus_code !=
+		    isc->formats_list[i].mbus_code)
+			continue;
+		if (supported_index == index) {
+			f->pixelformat = isc->formats_list[i].fourcc;
+			return 0;
+		}
+		supported_index++;
 	}
 
-	index -= isc->controller_formats_size;
+	/*
+	 * If the sensor does not support this mbus_code whatsoever,
+	 * there is no reason to advertise any of our output formats
+	 */
+	if (supported_index == 0)
+		return -EINVAL;
 
+	/*
+	 * If the sensor uses a format that is not raw, then we cannot
+	 * convert it to any of the formats that we usually can with a
+	 * RAW sensor. Thus, do not advertise them.
+	 */
+	if (isc->config.sd_format &&
+	    !ISC_IS_FORMAT_RAW(isc->config.sd_format->mbus_code))
+		return -EINVAL;
+
+	/*
+	 * Iterate again through the formats that we can convert to.
+	 * However, to avoid duplicates, skip the formats that
+	 * the sensor already supports directly
+	 */
+	index -= supported_index;
 	supported_index = 0;
 
-	for (i = 0; i < isc->formats_list_size; i++) {
-		if (!ISC_IS_FORMAT_RAW(isc->formats_list[i].mbus_code) ||
-		    !isc->formats_list[i].sd_support)
+	for (i = 0; i < isc->controller_formats_size; i++) {
+		/* if this format is already supported by sensor, skip it */
+		if (find_format_by_fourcc(isc, isc->controller_formats[i].fourcc))
 			continue;
 		if (supported_index == index) {
-			f->pixelformat = isc->formats_list[i].fourcc;
+			f->pixelformat =
+				isc->controller_formats[i].fourcc;
 			return 0;
 		}
 		supported_index++;
@@ -581,20 +621,30 @@  static int isc_try_validate_formats(struct isc_device *isc)
 		break;
 	default:
 	/* any other different formats are not supported */
+		v4l2_err(&isc->v4l2_dev, "Requested unsupported format.\n");
 		ret = -EINVAL;
 	}
 	v4l2_dbg(1, debug, &isc->v4l2_dev,
 		 "Format validation, requested rgb=%u, yuv=%u, grey=%u, bayer=%u\n",
 		 rgb, yuv, grey, bayer);
 
-	/* we cannot output RAW if we do not receive RAW */
-	if ((bayer) && !ISC_IS_FORMAT_RAW(isc->try_config.sd_format->mbus_code))
+	if ((bayer) &&
+	    !ISC_IS_FORMAT_RAW(isc->try_config.sd_format->mbus_code)) {
+		v4l2_err(&isc->v4l2_dev, "Cannot output RAW if we do not receive RAW.\n");
 		return -EINVAL;
+	}
 
-	/* we cannot output GREY if we do not receive RAW/GREY */
 	if (grey && !ISC_IS_FORMAT_RAW(isc->try_config.sd_format->mbus_code) &&
-	    !ISC_IS_FORMAT_GREY(isc->try_config.sd_format->mbus_code))
+	    !ISC_IS_FORMAT_GREY(isc->try_config.sd_format->mbus_code)) {
+		v4l2_err(&isc->v4l2_dev, "Cannot output GREY if we do not receive RAW/GREY.\n");
+		return -EINVAL;
+	}
+
+	if ((rgb || bayer || yuv) &&
+	    ISC_IS_FORMAT_GREY(isc->try_config.sd_format->mbus_code)) {
+		v4l2_err(&isc->v4l2_dev, "Cannot convert GREY to another format.\n");
 		return -EINVAL;
+	}
 
 	return ret;
 }
@@ -822,7 +872,7 @@  static void isc_try_fse(struct isc_device *isc,
 	 * If we do not know yet which format the subdev is using, we cannot
 	 * do anything.
 	 */
-	if (!isc->try_config.sd_format)
+	if (!isc->config.sd_format)
 		return;
 
 	fse.code = isc->try_config.sd_format->mbus_code;
@@ -843,180 +893,141 @@  static void isc_try_fse(struct isc_device *isc,
 	}
 }
 
-static int isc_try_fmt(struct isc_device *isc, struct v4l2_format *f,
-			u32 *code)
+static int isc_try_fmt(struct isc_device *isc, struct v4l2_format *f)
 {
-	int i;
-	struct isc_format *sd_fmt = NULL, *direct_fmt = NULL;
 	struct v4l2_pix_format *pixfmt = &f->fmt.pix;
-	struct v4l2_subdev_pad_config pad_cfg = {};
-	struct v4l2_subdev_state pad_state = {
-		.pads = &pad_cfg
-		};
-	struct v4l2_subdev_format format = {
-		.which = V4L2_SUBDEV_FORMAT_TRY,
-	};
-	u32 mbus_code;
-	int ret;
-	bool rlp_dma_direct_dump = false;
+	unsigned int i;
 
 	if (f->type != V4L2_BUF_TYPE_VIDEO_CAPTURE)
 		return -EINVAL;
 
-	/* Step 1: find a RAW format that is supported */
-	for (i = 0; i < isc->num_user_formats; i++) {
-		if (ISC_IS_FORMAT_RAW(isc->user_formats[i]->mbus_code)) {
-			sd_fmt = isc->user_formats[i];
+	isc->try_config.fourcc = isc->user_formats[0]->fourcc;
+
+	/* find if the format requested is supported */
+	for (i = 0; i < isc->controller_formats_size; i++)
+		if (isc->controller_formats[i].fourcc == pixfmt->pixelformat) {
+			isc->try_config.fourcc = pixfmt->pixelformat;
 			break;
 		}
-	}
-	/* Step 2: We can continue with this RAW format, or we can look
-	 * for better: maybe sensor supports directly what we need.
-	 */
-	direct_fmt = find_format_by_fourcc(isc, pixfmt->pixelformat);
-
-	/* Step 3: We have both. We decide given the module parameter which
-	 * one to use.
-	 */
-	if (direct_fmt && sd_fmt && sensor_preferred)
-		sd_fmt = direct_fmt;
-
-	/* Step 4: we do not have RAW but we have a direct format. Use it. */
-	if (direct_fmt && !sd_fmt)
-		sd_fmt = direct_fmt;
-
-	/* Step 5: if we are using a direct format, we need to package
-	 * everything as 8 bit data and just dump it
-	 */
-	if (sd_fmt == direct_fmt)
-		rlp_dma_direct_dump = true;
-
-	/* Step 6: We have no format. This can happen if the userspace
-	 * requests some weird/invalid format.
-	 * In this case, default to whatever we have
-	 */
-	if (!sd_fmt && !direct_fmt) {
-		sd_fmt = isc->user_formats[isc->num_user_formats - 1];
-		v4l2_dbg(1, debug, &isc->v4l2_dev,
-			 "Sensor not supporting %.4s, using %.4s\n",
-			 (char *)&pixfmt->pixelformat, (char *)&sd_fmt->fourcc);
-	}
-
-	if (!sd_fmt) {
-		ret = -EINVAL;
-		goto isc_try_fmt_err;
-	}
-
-	/* Step 7: Print out what we decided for debugging */
-	v4l2_dbg(1, debug, &isc->v4l2_dev,
-		 "Preferring to have sensor using format %.4s\n",
-		 (char *)&sd_fmt->fourcc);
-
-	/* Step 8: at this moment we decided which format the subdev will use */
-	isc->try_config.sd_format = sd_fmt;
-
-	/* Limit to Atmel ISC hardware capabilities */
-	if (pixfmt->width > isc->max_width)
-		pixfmt->width = isc->max_width;
-	if (pixfmt->height > isc->max_height)
-		pixfmt->height = isc->max_height;
-
-	/*
-	 * The mbus format is the one the subdev outputs.
-	 * The pixels will be transferred in this format Sensor -> ISC
-	 */
-	mbus_code = sd_fmt->mbus_code;
-
-	/*
-	 * Validate formats. If the required format is not OK, default to raw.
-	 */
-
-	isc->try_config.fourcc = pixfmt->pixelformat;
-
-	if (isc_try_validate_formats(isc)) {
-		pixfmt->pixelformat = isc->try_config.fourcc = sd_fmt->fourcc;
-		/* Re-try to validate the new format */
-		ret = isc_try_validate_formats(isc);
-		if (ret)
-			goto isc_try_fmt_err;
-	}
-
-	ret = isc_try_configure_rlp_dma(isc, rlp_dma_direct_dump);
-	if (ret)
-		goto isc_try_fmt_err;
-
-	ret = isc_try_configure_pipeline(isc);
-	if (ret)
-		goto isc_try_fmt_err;
 
-	/* Obtain frame sizes if possible to have crop requirements ready */
-	isc_try_fse(isc, &pad_state);
-
-	v4l2_fill_mbus_format(&format.format, pixfmt, mbus_code);
-	ret = v4l2_subdev_call(isc->current_subdev->sd, pad, set_fmt,
-			       &pad_state, &format);
-	if (ret < 0)
-		goto isc_try_fmt_subdev_err;
+	/* If we did not find the requested format, we will fallback here */
+	pixfmt->pixelformat = isc->try_config.fourcc;
+	pixfmt->colorspace = V4L2_COLORSPACE_SRGB;
+	pixfmt->field = V4L2_FIELD_NONE;
 
-	v4l2_fill_pix_format(pixfmt, &format.format);
+	isc_try_configure_rlp_dma(isc, false);
 
 	/* Limit to Atmel ISC hardware capabilities */
-	if (pixfmt->width > isc->max_width)
-		pixfmt->width = isc->max_width;
-	if (pixfmt->height > isc->max_height)
-		pixfmt->height = isc->max_height;
+	v4l_bound_align_image(&pixfmt->width, 16, isc->max_width, 0,
+			      &pixfmt->height, 16, isc->max_height, 0, 0);
 
 	pixfmt->field = V4L2_FIELD_NONE;
 	pixfmt->bytesperline = (pixfmt->width * isc->try_config.bpp_v4l2) >> 3;
 	pixfmt->sizeimage = ((pixfmt->width * isc->try_config.bpp) >> 3) *
 			     pixfmt->height;
 
-	if (code)
-		*code = mbus_code;
+	isc->try_fmt = *f;
 
 	return 0;
+}
 
-isc_try_fmt_err:
-	v4l2_err(&isc->v4l2_dev, "Could not find any possible format for a working pipeline\n");
-isc_try_fmt_subdev_err:
-	memset(&isc->try_config, 0, sizeof(isc->try_config));
+static int isc_set_fmt(struct isc_device *isc, struct v4l2_format *f)
+{
+	isc_try_fmt(isc, f);
 
-	return ret;
+	/* make the try configuration active */
+	isc->config = isc->try_config;
+	isc->fmt = isc->try_fmt;
+
+	v4l2_dbg(1, debug, &isc->v4l2_dev, "ISC set_fmt to %.4s @%dx%d\n",
+		 (char *)&f->fmt.pix.pixelformat,
+		 f->fmt.pix.width, f->fmt.pix.height);
+
+	return 0;
 }
 
-static int isc_set_fmt(struct isc_device *isc, struct v4l2_format *f)
+static int isc_validate(struct isc_device *isc)
 {
+	int ret;
+	int i;
+	struct isc_format *sd_fmt = NULL;
+	struct v4l2_pix_format *pixfmt = &isc->fmt.fmt.pix;
 	struct v4l2_subdev_format format = {
 		.which = V4L2_SUBDEV_FORMAT_ACTIVE,
+		.pad = isc->remote_pad,
+	};
+	struct v4l2_subdev_pad_config pad_cfg = {};
+	struct v4l2_subdev_state pad_state = {
+		.pads = &pad_cfg,
 	};
-	u32 mbus_code = 0;
-	int ret;
 
-	ret = isc_try_fmt(isc, f, &mbus_code);
+	/* Get current format from subdev */
+	ret = v4l2_subdev_call(isc->current_subdev->sd, pad, get_fmt, NULL,
+			       &format);
 	if (ret)
 		return ret;
 
-	v4l2_fill_mbus_format(&format.format, &f->fmt.pix, mbus_code);
-	ret = v4l2_subdev_call(isc->current_subdev->sd, pad,
-			       set_fmt, NULL, &format);
-	if (ret < 0)
-		return ret;
+	/* Identify the subdev's format configuration */
+	for (i = 0; i < isc->num_user_formats; i++)
+		if (isc->user_formats[i]->mbus_code == format.format.code) {
+			sd_fmt = isc->user_formats[i];
+			break;
+		}
+
+	/* Check if the format is not supported */
+	if (!sd_fmt) {
+		v4l2_err(&isc->v4l2_dev,
+			 "Current subdevice is streaming a media bus code that is not supported 0x%x\n",
+			 format.format.code);
+		return -EPIPE;
+	}
+
+	/* At this moment we know which format the subdev will use */
+	isc->try_config.sd_format = sd_fmt;
+
+	/* If the sensor is not RAW, we can only do a direct dump */
+	if (!ISC_IS_FORMAT_RAW(isc->try_config.sd_format->mbus_code))
+		isc_try_configure_rlp_dma(isc, true);
 
 	/* Limit to Atmel ISC hardware capabilities */
-	if (f->fmt.pix.width > isc->max_width)
-		f->fmt.pix.width = isc->max_width;
-	if (f->fmt.pix.height > isc->max_height)
-		f->fmt.pix.height = isc->max_height;
+	v4l_bound_align_image(&format.format.width, 16, isc->max_width, 0,
+			      &format.format.height, 16, isc->max_height, 0, 0);
+
+	/* Check if the frame size is the same. Otherwise we may overflow */
+	if (pixfmt->height != format.format.height ||
+	    pixfmt->width != format.format.width) {
+		v4l2_err(&isc->v4l2_dev,
+			 "ISC not configured with the proper frame size: %dx%d\n",
+			 format.format.width, format.format.height);
+		return -EPIPE;
+	}
 
-	isc->fmt = *f;
+	v4l2_dbg(1, debug, &isc->v4l2_dev,
+		 "Identified subdev using format %.4s with %dx%d %d bpp\n",
+		 (char *)&sd_fmt->fourcc, pixfmt->width, pixfmt->height,
+		 isc->try_config.bpp);
 
+	/* Reset and restart AWB if the subdevice changed the format */
 	if (isc->try_config.sd_format && isc->config.sd_format &&
 	    isc->try_config.sd_format != isc->config.sd_format) {
 		isc->ctrls.hist_stat = HIST_INIT;
 		isc_reset_awb_ctrls(isc);
 		isc_update_v4l2_ctrls(isc);
 	}
-	/* make the try configuration active */
+
+	/* Validate formats */
+	ret = isc_try_validate_formats(isc);
+	if (ret)
+		return ret;
+
+	/* Obtain frame sizes if possible to have crop requirements ready */
+	isc_try_fse(isc, &pad_state);
+
+	/* Configure ISC pipeline for the config */
+	ret = isc_try_configure_pipeline(isc);
+	if (ret)
+		return ret;
+
 	isc->config = isc->try_config;
 
 	v4l2_dbg(1, debug, &isc->v4l2_dev, "New ISC configuration in place\n");
@@ -1040,7 +1051,7 @@  static int isc_try_fmt_vid_cap(struct file *file, void *priv,
 {
 	struct isc_device *isc = video_drvdata(file);
 
-	return isc_try_fmt(isc, f, NULL);
+	return isc_try_fmt(isc, f);
 }
 
 static int isc_enum_input(struct file *file, void *priv,
@@ -1841,7 +1852,7 @@  static int isc_set_default_fmt(struct isc_device *isc)
 	};
 	int ret;
 
-	ret = isc_try_fmt(isc, &f, NULL);
+	ret = isc_try_fmt(isc, &f);
 	if (ret)
 		return ret;
 
@@ -2015,6 +2026,24 @@  int isc_pipeline_init(struct isc_device *isc)
 }
 EXPORT_SYMBOL_GPL(isc_pipeline_init);
 
+int isc_link_validate(struct media_link *link)
+{
+	struct video_device *vdev =
+		media_entity_to_video_device(link->sink->entity);
+	struct isc_device *isc = video_get_drvdata(vdev);
+	int ret;
+
+	ret = v4l2_subdev_link_validate(link);
+	if (ret)
+		return ret;
+
+	return isc_validate(isc);
+}
+
+static const struct media_entity_operations isc_entity_operations = {
+	.link_validate = isc_link_validate,
+};
+
 int isc_mc_init(struct isc_device *isc, u32 ver)
 {
 	const struct of_device_id *match;
@@ -2022,6 +2051,8 @@  int isc_mc_init(struct isc_device *isc, u32 ver)
 
 	isc->video_dev.entity.function = MEDIA_ENT_F_IO_V4L;
 	isc->video_dev.entity.flags = MEDIA_ENT_FL_DEFAULT;
+	isc->video_dev.entity.ops = &isc_entity_operations;
+
 	isc->pads[ISC_PAD_SINK].flags = MEDIA_PAD_FL_SINK;
 
 	ret = media_entity_pads_init(&isc->video_dev.entity, ISC_PADS_NUM,
diff --git a/drivers/media/platform/atmel/atmel-isc-scaler.c b/drivers/media/platform/atmel/atmel-isc-scaler.c
index ec95c9665883..93375a61aea6 100644
--- a/drivers/media/platform/atmel/atmel-isc-scaler.c
+++ b/drivers/media/platform/atmel/atmel-isc-scaler.c
@@ -155,6 +155,10 @@  static const struct v4l2_subdev_pad_ops isc_scaler_pad_ops = {
 	.init_cfg = isc_scaler_init_cfg,
 };
 
+static const struct media_entity_operations isc_scaler_entity_ops = {
+	.link_validate = v4l2_subdev_link_validate,
+};
+
 static const struct v4l2_subdev_ops xisc_scaler_subdev_ops = {
 	.pad = &isc_scaler_pad_ops,
 };
@@ -172,6 +176,7 @@  int isc_scaler_init(struct isc_device *isc)
 
 	isc->scaler_sd.flags |= V4L2_SUBDEV_FL_HAS_DEVNODE;
 	isc->scaler_sd.entity.function = MEDIA_ENT_F_PROC_VIDEO_SCALER;
+	isc->scaler_sd.entity.ops = &isc_scaler_entity_ops;
 	isc->scaler_pads[ISC_SCALER_PAD_SINK].flags = MEDIA_PAD_FL_SINK;
 	isc->scaler_pads[ISC_SCALER_PAD_SOURCE].flags = MEDIA_PAD_FL_SOURCE;
 
diff --git a/drivers/media/platform/atmel/atmel-isc.h b/drivers/media/platform/atmel/atmel-isc.h
index 04ea5e340808..e36cf9d3942a 100644
--- a/drivers/media/platform/atmel/atmel-isc.h
+++ b/drivers/media/platform/atmel/atmel-isc.h
@@ -270,6 +270,7 @@  enum isc_scaler_pads {
  * @formats_list_size:	size of formats_list array
  * @pads:		media controller pads for isc video entity
  * @mdev:		media device that is registered by the isc
+ * @mpipe:		media device pipeline used by the isc
  * @remote_pad:		remote pad on the connected subdevice
  * @scaler_sd:		subdevice for the scaler that isc registers
  * @scaler_pads:	media controller pads for the scaler subdevice
@@ -295,6 +296,7 @@  struct isc_device {
 	struct completion	comp;
 
 	struct v4l2_format	fmt;
+	struct v4l2_format	try_fmt;
 	struct isc_format	**user_formats;
 	unsigned int		num_user_formats;
 
@@ -366,6 +368,7 @@  struct isc_device {
 	struct {
 		struct media_pad		pads[ISC_PADS_NUM];
 		struct media_device		mdev;
+		struct media_pipeline		mpipe;
 
 		u32				remote_pad;
 	};