drivers/media/platform/vimc/vimc-scaler.c - linux-mtk - Git at Google

 /*
  * vimc-scaler.c Virtual Media Controller Driver
  *
  * Copyright (C) 2015-2017 Helen Koike <helen.fornazier@gmail.com>
  *
  * This program is free software; you can redistribute it and/or modify
  * it under the terms of the GNU General Public License as published by
  * the Free Software Foundation; either version 2 of the License, or
  * (at your option) any later version.
  *
  * This program is distributed in the hope that it will be useful,
  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  * GNU General Public License for more details.
  *
  */

 #include <linux/component.h>
 #include <linux/module.h>
 #include <linux/mod_devicetable.h>
 #include <linux/platform_device.h>
 #include <linux/vmalloc.h>
 #include <linux/v4l2-mediabus.h>
 #include <media/v4l2-subdev.h>

 #include "vimc-common.h"

 #define VIMC_SCA_DRV_NAME "vimc-scaler"

 static unsigned int sca_mult = 3;
 module_param(sca_mult, uint, 0000);
 MODULE_PARM_DESC(sca_mult, " the image size multiplier");

 #define IS_SINK(pad)	(!pad)
 #define IS_SRC(pad)	(pad)
 #define MAX_ZOOM	8

 struct vimc_sca_device {
 	struct vimc_ent_device ved;
 	struct v4l2_subdev sd;
 	struct device *dev;
 	/* NOTE: the source fmt is the same as the sink
 	 * with the width and hight multiplied by mult
 	 */
 	struct v4l2_mbus_framefmt sink_fmt;
 	/* Values calculated when the stream starts */
 	u8 *src_frame;
 	unsigned int src_line_size;
 	unsigned int bpp;
 };

 static const struct v4l2_mbus_framefmt sink_fmt_default = {
 	.width = 640,
 	.height = 480,
 	.code = MEDIA_BUS_FMT_RGB888_1X24,
 	.field = V4L2_FIELD_NONE,
 	.colorspace = V4L2_COLORSPACE_DEFAULT,
 };

 static int vimc_sca_init_cfg(struct v4l2_subdev *sd,
 			     struct v4l2_subdev_pad_config *cfg)
 {
 	struct v4l2_mbus_framefmt *mf;
 	unsigned int i;

 	mf = v4l2_subdev_get_try_format(sd, cfg, 0);
 	*mf = sink_fmt_default;

 	for (i = 1; i < sd->entity.num_pads; i++) {
 		mf = v4l2_subdev_get_try_format(sd, cfg, i);
 		*mf = sink_fmt_default;
 		mf->width = mf->width * sca_mult;
 		mf->height = mf->height * sca_mult;
 	}

 	return 0;
 }

 static int vimc_sca_enum_mbus_code(struct v4l2_subdev *sd,
 				   struct v4l2_subdev_pad_config *cfg,
 				   struct v4l2_subdev_mbus_code_enum *code)
 {
 	const struct vimc_pix_map *vpix = vimc_pix_map_by_index(code->index);

 	/* We don't support bayer format */
 	if (!vpix || vpix->bayer)
 		return -EINVAL;

 	code->code = vpix->code;

 	return 0;
 }

 static int vimc_sca_enum_frame_size(struct v4l2_subdev *sd,
 				    struct v4l2_subdev_pad_config *cfg,
 				    struct v4l2_subdev_frame_size_enum *fse)
 {
 	const struct vimc_pix_map *vpix;

 	if (fse->index)
 		return -EINVAL;

 	/* Only accept code in the pix map table in non bayer format */
 	vpix = vimc_pix_map_by_code(fse->code);
 	if (!vpix || vpix->bayer)
 		return -EINVAL;

 	fse->min_width = VIMC_FRAME_MIN_WIDTH;
 	fse->min_height = VIMC_FRAME_MIN_HEIGHT;

 	if (IS_SINK(fse->pad)) {
 		fse->max_width = VIMC_FRAME_MAX_WIDTH;
 		fse->max_height = VIMC_FRAME_MAX_HEIGHT;
 	} else {
 		fse->max_width = VIMC_FRAME_MAX_WIDTH * MAX_ZOOM;
 		fse->max_height = VIMC_FRAME_MAX_HEIGHT * MAX_ZOOM;
 	}

 	return 0;
 }

 static int vimc_sca_get_fmt(struct v4l2_subdev *sd,
 			    struct v4l2_subdev_pad_config *cfg,
 			    struct v4l2_subdev_format *format)
 {
 	struct vimc_sca_device *vsca = v4l2_get_subdevdata(sd);

 	/* Get the current sink format */
 	format->format = (format->which == V4L2_SUBDEV_FORMAT_TRY) ?
 			 *v4l2_subdev_get_try_format(sd, cfg, 0) :
 			 vsca->sink_fmt;

 	/* Scale the frame size for the source pad */
 	if (IS_SRC(format->pad)) {
 		format->format.width = vsca->sink_fmt.width * sca_mult;
 		format->format.height = vsca->sink_fmt.height * sca_mult;
 	}

 	return 0;
 }

 static void vimc_sca_adjust_sink_fmt(struct v4l2_mbus_framefmt *fmt)
 {
 	const struct vimc_pix_map *vpix;

 	/* Only accept code in the pix map table in non bayer format */
 	vpix = vimc_pix_map_by_code(fmt->code);
 	if (!vpix || vpix->bayer)
 		fmt->code = sink_fmt_default.code;

 	fmt->width = clamp_t(u32, fmt->width, VIMC_FRAME_MIN_WIDTH,
 			     VIMC_FRAME_MAX_WIDTH) & ~1;
 	fmt->height = clamp_t(u32, fmt->height, VIMC_FRAME_MIN_HEIGHT,
 			      VIMC_FRAME_MAX_HEIGHT) & ~1;

 	if (fmt->field == V4L2_FIELD_ANY)
 		fmt->field = sink_fmt_default.field;

 	vimc_colorimetry_clamp(fmt);
 }

 static int vimc_sca_set_fmt(struct v4l2_subdev *sd,
 			    struct v4l2_subdev_pad_config *cfg,
 			    struct v4l2_subdev_format *fmt)
 {
 	struct vimc_sca_device *vsca = v4l2_get_subdevdata(sd);
 	struct v4l2_mbus_framefmt *sink_fmt;

 	if (fmt->which == V4L2_SUBDEV_FORMAT_ACTIVE) {
 		/* Do not change the format while stream is on */
 		if (vsca->src_frame)
 			return -EBUSY;

 		sink_fmt = &vsca->sink_fmt;
 	} else {
 		sink_fmt = v4l2_subdev_get_try_format(sd, cfg, 0);
 	}

 	/*
 	 * Do not change the format of the source pad,
 	 * it is propagated from the sink
 	 */
 	if (IS_SRC(fmt->pad)) {
 		fmt->format = *sink_fmt;
 		fmt->format.width = sink_fmt->width * sca_mult;
 		fmt->format.height = sink_fmt->height * sca_mult;
 	} else {
 		/* Set the new format in the sink pad */
 		vimc_sca_adjust_sink_fmt(&fmt->format);

 		dev_dbg(vsca->dev, "%s: sink format update: "
 			"old:%dx%d (0x%x, %d, %d, %d, %d) "
 			"new:%dx%d (0x%x, %d, %d, %d, %d)\n", vsca->sd.name,
 			/* old */
 			sink_fmt->width, sink_fmt->height, sink_fmt->code,
 			sink_fmt->colorspace, sink_fmt->quantization,
 			sink_fmt->xfer_func, sink_fmt->ycbcr_enc,
 			/* new */
 			fmt->format.width, fmt->format.height, fmt->format.code,
 			fmt->format.colorspace,	fmt->format.quantization,
 			fmt->format.xfer_func, fmt->format.ycbcr_enc);

 		*sink_fmt = fmt->format;
 	}

 	return 0;
 }

 static const struct v4l2_subdev_pad_ops vimc_sca_pad_ops = {
 	.init_cfg		= vimc_sca_init_cfg,
 	.enum_mbus_code		= vimc_sca_enum_mbus_code,
 	.enum_frame_size	= vimc_sca_enum_frame_size,
 	.get_fmt		= vimc_sca_get_fmt,
 	.set_fmt		= vimc_sca_set_fmt,
 };

 static int vimc_sca_s_stream(struct v4l2_subdev *sd, int enable)
 {
 	struct vimc_sca_device *vsca = v4l2_get_subdevdata(sd);

 	if (enable) {
 		const struct vimc_pix_map *vpix;
 		unsigned int frame_size;

 		if (vsca->src_frame)
 			return 0;

 		/* Save the bytes per pixel of the sink */
 		vpix = vimc_pix_map_by_code(vsca->sink_fmt.code);
 		vsca->bpp = vpix->bpp;

 		/* Calculate the width in bytes of the src frame */
 		vsca->src_line_size = vsca->sink_fmt.width *
 				      sca_mult * vsca->bpp;

 		/* Calculate the frame size of the source pad */
 		frame_size = vsca->src_line_size * vsca->sink_fmt.height *
 			     sca_mult;

 		/* Allocate the frame buffer. Use vmalloc to be able to
 		 * allocate a large amount of memory
 		 */
 		vsca->src_frame = vmalloc(frame_size);
 		if (!vsca->src_frame)
 			return -ENOMEM;

 	} else {
 		if (!vsca->src_frame)
 			return 0;

 		vfree(vsca->src_frame);
 		vsca->src_frame = NULL;
 	}

 	return 0;
 }

 static const struct v4l2_subdev_video_ops vimc_sca_video_ops = {
 	.s_stream = vimc_sca_s_stream,
 };

 static const struct v4l2_subdev_ops vimc_sca_ops = {
 	.pad = &vimc_sca_pad_ops,
 	.video = &vimc_sca_video_ops,
 };

 static void vimc_sca_fill_pix(u8 *const ptr,
 			      const u8 *const pixel,
 			      const unsigned int bpp)
 {
 	unsigned int i;

 	/* copy the pixel to the pointer */
 	for (i = 0; i < bpp; i++)
 		ptr[i] = pixel[i];
 }

 static void vimc_sca_scale_pix(const struct vimc_sca_device *const vsca,
 			       const unsigned int lin, const unsigned int col,
 			       const u8 *const sink_frame)
 {
 	unsigned int i, j, index;
 	const u8 *pixel;

 	/* Point to the pixel value in position (lin, col) in the sink frame */
 	index = VIMC_FRAME_INDEX(lin, col,
 				 vsca->sink_fmt.width,
 				 vsca->bpp);
 	pixel = &sink_frame[index];

 	dev_dbg(vsca->dev,
 		"sca: %s: --- scale_pix sink pos %dx%d, index %d ---\n",
 		vsca->sd.name, lin, col, index);

 	/* point to the place we are going to put the first pixel
 	 * in the scaled src frame
 	 */
 	index = VIMC_FRAME_INDEX(lin * sca_mult, col * sca_mult,
 				 vsca->sink_fmt.width * sca_mult, vsca->bpp);

 	dev_dbg(vsca->dev, "sca: %s: scale_pix src pos %dx%d, index %d\n",
 		vsca->sd.name, lin * sca_mult, col * sca_mult, index);

 	/* Repeat this pixel mult times */
 	for (i = 0; i < sca_mult; i++) {
 		/* Iterate through each beginning of a
 		 * pixel repetition in a line
 		 */
 		for (j = 0; j < sca_mult * vsca->bpp; j += vsca->bpp) {
 			dev_dbg(vsca->dev,
 				"sca: %s: sca: scale_pix src pos %d\n",
 				vsca->sd.name, index + j);

 			/* copy the pixel to the position index + j */
 			vimc_sca_fill_pix(&vsca->src_frame[index + j],
 					  pixel, vsca->bpp);
 		}

 		/* move the index to the next line */
 		index += vsca->src_line_size;
 	}
 }

 static void vimc_sca_fill_src_frame(const struct vimc_sca_device *const vsca,
 				    const u8 *const sink_frame)
 {
 	unsigned int i, j;

 	/* Scale each pixel from the original sink frame */
 	/* TODO: implement scale down, only scale up is supported for now */
 	for (i = 0; i < vsca->sink_fmt.height; i++)
 		for (j = 0; j < vsca->sink_fmt.width; j++)
 			vimc_sca_scale_pix(vsca, i, j, sink_frame);
 }

 static void *vimc_sca_process_frame(struct vimc_ent_device *ved,
 				    const void *sink_frame)
 {
 	struct vimc_sca_device *vsca = container_of(ved, struct vimc_sca_device,
 						    ved);

 	/* If the stream in this node is not active, just return */
 	if (!vsca->src_frame)
 		return ERR_PTR(-EINVAL);

 	vimc_sca_fill_src_frame(vsca, sink_frame);

 	return vsca->src_frame;
 };

 static void vimc_sca_comp_unbind(struct device *comp, struct device *master,
 				 void *master_data)
 {
 	struct vimc_ent_device *ved = dev_get_drvdata(comp);
 	struct vimc_sca_device *vsca = container_of(ved, struct vimc_sca_device,
 						    ved);

 	vimc_ent_sd_unregister(ved, &vsca->sd);
 	kfree(vsca);
 }


 static int vimc_sca_comp_bind(struct device *comp, struct device *master,
 			      void *master_data)
 {
 	struct v4l2_device *v4l2_dev = master_data;
 	struct vimc_platform_data *pdata = comp->platform_data;
 	struct vimc_sca_device *vsca;
 	int ret;

 	/* Allocate the vsca struct */
 	vsca = kzalloc(sizeof(*vsca), GFP_KERNEL);
 	if (!vsca)
 		return -ENOMEM;

 	/* Initialize ved and sd */
 	ret = vimc_ent_sd_register(&vsca->ved, &vsca->sd, v4l2_dev,
 				   pdata->entity_name,
 				   MEDIA_ENT_F_PROC_VIDEO_SCALER, 2,
 				   (const unsigned long[2]) {MEDIA_PAD_FL_SINK,
 				   MEDIA_PAD_FL_SOURCE},
 				   &vimc_sca_ops);
 	if (ret) {
 		kfree(vsca);
 		return ret;
 	}

 	vsca->ved.process_frame = vimc_sca_process_frame;
 	dev_set_drvdata(comp, &vsca->ved);
 	vsca->dev = comp;

 	/* Initialize the frame format */
 	vsca->sink_fmt = sink_fmt_default;

 	return 0;
 }

 static const struct component_ops vimc_sca_comp_ops = {
 	.bind = vimc_sca_comp_bind,
 	.unbind = vimc_sca_comp_unbind,
 };

 static int vimc_sca_probe(struct platform_device *pdev)
 {
 	return component_add(&pdev->dev, &vimc_sca_comp_ops);
 }

 static int vimc_sca_remove(struct platform_device *pdev)
 {
 	component_del(&pdev->dev, &vimc_sca_comp_ops);

 	return 0;
 }

 static const struct platform_device_id vimc_sca_driver_ids[] = {
 	{
 		.name           = VIMC_SCA_DRV_NAME,
 	},
 	{ }
 };

 static struct platform_driver vimc_sca_pdrv = {
 	.probe		= vimc_sca_probe,
 	.remove		= vimc_sca_remove,
 	.id_table	= vimc_sca_driver_ids,
 	.driver		= {
 		.name	= VIMC_SCA_DRV_NAME,
 	},
 };

 module_platform_driver(vimc_sca_pdrv);

 MODULE_DEVICE_TABLE(platform, vimc_sca_driver_ids);

 MODULE_DESCRIPTION("Virtual Media Controller Driver (VIMC) Scaler");
 MODULE_AUTHOR("Helen Mae Koike Fornazier <helen.fornazier@gmail.com>");
 MODULE_LICENSE("GPL");
	/*
	* vimc-scaler.c Virtual Media Controller Driver
	*
	* Copyright (C) 2015-2017 Helen Koike <helen.fornazier@gmail.com>
	*
	* This program is free software; you can redistribute it and/or modify
	* it under the terms of the GNU General Public License as published by
	* the Free Software Foundation; either version 2 of the License, or
	* (at your option) any later version.
	*
	* This program is distributed in the hope that it will be useful,
	* but WITHOUT ANY WARRANTY; without even the implied warranty of
	* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
	* GNU General Public License for more details.
	*
	*/

	#include <linux/component.h>
	#include <linux/module.h>
	#include <linux/mod_devicetable.h>
	#include <linux/platform_device.h>
	#include <linux/vmalloc.h>
	#include <linux/v4l2-mediabus.h>
	#include <media/v4l2-subdev.h>

	#include "vimc-common.h"

	#define VIMC_SCA_DRV_NAME "vimc-scaler"

	static unsigned int sca_mult = 3;
	module_param(sca_mult, uint, 0000);
	MODULE_PARM_DESC(sca_mult, " the image size multiplier");

	#define IS_SINK(pad) (!pad)
	#define IS_SRC(pad) (pad)
	#define MAX_ZOOM 8

	struct vimc_sca_device {
	struct vimc_ent_device ved;
	struct v4l2_subdev sd;
	struct device *dev;
	/* NOTE: the source fmt is the same as the sink
	* with the width and hight multiplied by mult
	*/
	struct v4l2_mbus_framefmt sink_fmt;
	/* Values calculated when the stream starts */
	u8 *src_frame;
	unsigned int src_line_size;
	unsigned int bpp;
	};

	static const struct v4l2_mbus_framefmt sink_fmt_default = {
	.width = 640,
	.height = 480,
	.code = MEDIA_BUS_FMT_RGB888_1X24,
	.field = V4L2_FIELD_NONE,
	.colorspace = V4L2_COLORSPACE_DEFAULT,
	};

	static int vimc_sca_init_cfg(struct v4l2_subdev *sd,
	struct v4l2_subdev_pad_config *cfg)
	{
	struct v4l2_mbus_framefmt *mf;
	unsigned int i;

	mf = v4l2_subdev_get_try_format(sd, cfg, 0);
	*mf = sink_fmt_default;

	for (i = 1; i < sd->entity.num_pads; i++) {
	mf = v4l2_subdev_get_try_format(sd, cfg, i);
	*mf = sink_fmt_default;
	mf->width = mf->width * sca_mult;
	mf->height = mf->height * sca_mult;
	}

	return 0;
	}

	static int vimc_sca_enum_mbus_code(struct v4l2_subdev *sd,
	struct v4l2_subdev_pad_config *cfg,
	struct v4l2_subdev_mbus_code_enum *code)
	{
	const struct vimc_pix_map *vpix = vimc_pix_map_by_index(code->index);

	/* We don't support bayer format */
	if (!vpix \|\| vpix->bayer)
	return -EINVAL;

	code->code = vpix->code;

	return 0;
	}

	static int vimc_sca_enum_frame_size(struct v4l2_subdev *sd,
	struct v4l2_subdev_pad_config *cfg,
	struct v4l2_subdev_frame_size_enum *fse)
	{
	const struct vimc_pix_map *vpix;

	if (fse->index)
	return -EINVAL;

	/* Only accept code in the pix map table in non bayer format */
	vpix = vimc_pix_map_by_code(fse->code);
	if (!vpix \|\| vpix->bayer)
	return -EINVAL;

	fse->min_width = VIMC_FRAME_MIN_WIDTH;
	fse->min_height = VIMC_FRAME_MIN_HEIGHT;

	if (IS_SINK(fse->pad)) {
	fse->max_width = VIMC_FRAME_MAX_WIDTH;
	fse->max_height = VIMC_FRAME_MAX_HEIGHT;
	} else {
	fse->max_width = VIMC_FRAME_MAX_WIDTH * MAX_ZOOM;
	fse->max_height = VIMC_FRAME_MAX_HEIGHT * MAX_ZOOM;
	}

	return 0;
	}

	static int vimc_sca_get_fmt(struct v4l2_subdev *sd,
	struct v4l2_subdev_pad_config *cfg,
	struct v4l2_subdev_format *format)
	{
	struct vimc_sca_device *vsca = v4l2_get_subdevdata(sd);

	/* Get the current sink format */
	format->format = (format->which == V4L2_SUBDEV_FORMAT_TRY) ?
	*v4l2_subdev_get_try_format(sd, cfg, 0) :
	vsca->sink_fmt;

	/* Scale the frame size for the source pad */
	if (IS_SRC(format->pad)) {
	format->format.width = vsca->sink_fmt.width * sca_mult;
	format->format.height = vsca->sink_fmt.height * sca_mult;
	}

	return 0;
	}

	static void vimc_sca_adjust_sink_fmt(struct v4l2_mbus_framefmt *fmt)
	{
	const struct vimc_pix_map *vpix;

	/* Only accept code in the pix map table in non bayer format */
	vpix = vimc_pix_map_by_code(fmt->code);
	if (!vpix \|\| vpix->bayer)
	fmt->code = sink_fmt_default.code;

	fmt->width = clamp_t(u32, fmt->width, VIMC_FRAME_MIN_WIDTH,
	VIMC_FRAME_MAX_WIDTH) & ~1;
	fmt->height = clamp_t(u32, fmt->height, VIMC_FRAME_MIN_HEIGHT,
	VIMC_FRAME_MAX_HEIGHT) & ~1;

	if (fmt->field == V4L2_FIELD_ANY)
	fmt->field = sink_fmt_default.field;

	vimc_colorimetry_clamp(fmt);
	}

	static int vimc_sca_set_fmt(struct v4l2_subdev *sd,
	struct v4l2_subdev_pad_config *cfg,
	struct v4l2_subdev_format *fmt)
	{
	struct vimc_sca_device *vsca = v4l2_get_subdevdata(sd);
	struct v4l2_mbus_framefmt *sink_fmt;

	if (fmt->which == V4L2_SUBDEV_FORMAT_ACTIVE) {
	/* Do not change the format while stream is on */
	if (vsca->src_frame)
	return -EBUSY;

	sink_fmt = &vsca->sink_fmt;
	} else {
	sink_fmt = v4l2_subdev_get_try_format(sd, cfg, 0);
	}

	/*
	* Do not change the format of the source pad,
	* it is propagated from the sink
	*/
	if (IS_SRC(fmt->pad)) {
	fmt->format = *sink_fmt;
	fmt->format.width = sink_fmt->width * sca_mult;
	fmt->format.height = sink_fmt->height * sca_mult;
	} else {
	/* Set the new format in the sink pad */
	vimc_sca_adjust_sink_fmt(&fmt->format);

	dev_dbg(vsca->dev, "%s: sink format update: "
	"old:%dx%d (0x%x, %d, %d, %d, %d) "
	"new:%dx%d (0x%x, %d, %d, %d, %d)\n", vsca->sd.name,
	/* old */
	sink_fmt->width, sink_fmt->height, sink_fmt->code,
	sink_fmt->colorspace, sink_fmt->quantization,
	sink_fmt->xfer_func, sink_fmt->ycbcr_enc,
	/* new */
	fmt->format.width, fmt->format.height, fmt->format.code,
	fmt->format.colorspace, fmt->format.quantization,
	fmt->format.xfer_func, fmt->format.ycbcr_enc);

	*sink_fmt = fmt->format;
	}

	return 0;
	}

	static const struct v4l2_subdev_pad_ops vimc_sca_pad_ops = {
	.init_cfg = vimc_sca_init_cfg,
	.enum_mbus_code = vimc_sca_enum_mbus_code,
	.enum_frame_size = vimc_sca_enum_frame_size,
	.get_fmt = vimc_sca_get_fmt,
	.set_fmt = vimc_sca_set_fmt,
	};

	static int vimc_sca_s_stream(struct v4l2_subdev *sd, int enable)
	{
	struct vimc_sca_device *vsca = v4l2_get_subdevdata(sd);

	if (enable) {
	const struct vimc_pix_map *vpix;
	unsigned int frame_size;

	if (vsca->src_frame)
	return 0;

	/* Save the bytes per pixel of the sink */
	vpix = vimc_pix_map_by_code(vsca->sink_fmt.code);
	vsca->bpp = vpix->bpp;

	/* Calculate the width in bytes of the src frame */
	vsca->src_line_size = vsca->sink_fmt.width *
	sca_mult * vsca->bpp;

	/* Calculate the frame size of the source pad */
	frame_size = vsca->src_line_size * vsca->sink_fmt.height *
	sca_mult;

	/* Allocate the frame buffer. Use vmalloc to be able to
	* allocate a large amount of memory
	*/
	vsca->src_frame = vmalloc(frame_size);
	if (!vsca->src_frame)
	return -ENOMEM;

	} else {
	if (!vsca->src_frame)
	return 0;

	vfree(vsca->src_frame);
	vsca->src_frame = NULL;
	}

	return 0;
	}

	static const struct v4l2_subdev_video_ops vimc_sca_video_ops = {
	.s_stream = vimc_sca_s_stream,
	};

	static const struct v4l2_subdev_ops vimc_sca_ops = {
	.pad = &vimc_sca_pad_ops,
	.video = &vimc_sca_video_ops,
	};

	static void vimc_sca_fill_pix(u8 *const ptr,
	const u8 *const pixel,
	const unsigned int bpp)
	{
	unsigned int i;

	/* copy the pixel to the pointer */
	for (i = 0; i < bpp; i++)
	ptr[i] = pixel[i];
	}

	static void vimc_sca_scale_pix(const struct vimc_sca_device *const vsca,
	const unsigned int lin, const unsigned int col,
	const u8 *const sink_frame)
	{
	unsigned int i, j, index;
	const u8 *pixel;

	/* Point to the pixel value in position (lin, col) in the sink frame */
	index = VIMC_FRAME_INDEX(lin, col,
	vsca->sink_fmt.width,
	vsca->bpp);
	pixel = &sink_frame[index];

	dev_dbg(vsca->dev,
	"sca: %s: --- scale_pix sink pos %dx%d, index %d ---\n",
	vsca->sd.name, lin, col, index);

	/* point to the place we are going to put the first pixel
	* in the scaled src frame
	*/
	index = VIMC_FRAME_INDEX(lin * sca_mult, col * sca_mult,
	vsca->sink_fmt.width * sca_mult, vsca->bpp);

	dev_dbg(vsca->dev, "sca: %s: scale_pix src pos %dx%d, index %d\n",
	vsca->sd.name, lin * sca_mult, col * sca_mult, index);

	/* Repeat this pixel mult times */
	for (i = 0; i < sca_mult; i++) {
	/* Iterate through each beginning of a
	* pixel repetition in a line
	*/
	for (j = 0; j < sca_mult * vsca->bpp; j += vsca->bpp) {
	dev_dbg(vsca->dev,
	"sca: %s: sca: scale_pix src pos %d\n",
	vsca->sd.name, index + j);

	/* copy the pixel to the position index + j */
	vimc_sca_fill_pix(&vsca->src_frame[index + j],
	pixel, vsca->bpp);
	}

	/* move the index to the next line */
	index += vsca->src_line_size;
	}
	}

	static void vimc_sca_fill_src_frame(const struct vimc_sca_device *const vsca,
	const u8 *const sink_frame)
	{
	unsigned int i, j;

	/* Scale each pixel from the original sink frame */
	/* TODO: implement scale down, only scale up is supported for now */
	for (i = 0; i < vsca->sink_fmt.height; i++)
	for (j = 0; j < vsca->sink_fmt.width; j++)
	vimc_sca_scale_pix(vsca, i, j, sink_frame);
	}

	static void vimc_sca_process_frame(struct vimc_ent_device ved,
	const void *sink_frame)
	{
	struct vimc_sca_device *vsca = container_of(ved, struct vimc_sca_device,
	ved);

	/* If the stream in this node is not active, just return */
	if (!vsca->src_frame)
	return ERR_PTR(-EINVAL);

	vimc_sca_fill_src_frame(vsca, sink_frame);

	return vsca->src_frame;
	};

	static void vimc_sca_comp_unbind(struct device comp, struct device master,
	void *master_data)
	{
	struct vimc_ent_device *ved = dev_get_drvdata(comp);
	struct vimc_sca_device *vsca = container_of(ved, struct vimc_sca_device,
	ved);

	vimc_ent_sd_unregister(ved, &vsca->sd);
	kfree(vsca);
	}


	static int vimc_sca_comp_bind(struct device comp, struct device master,
	void *master_data)
	{
	struct v4l2_device *v4l2_dev = master_data;
	struct vimc_platform_data *pdata = comp->platform_data;
	struct vimc_sca_device *vsca;
	int ret;

	/* Allocate the vsca struct */
	vsca = kzalloc(sizeof(*vsca), GFP_KERNEL);
	if (!vsca)
	return -ENOMEM;

	/* Initialize ved and sd */
	ret = vimc_ent_sd_register(&vsca->ved, &vsca->sd, v4l2_dev,
	pdata->entity_name,
	MEDIA_ENT_F_PROC_VIDEO_SCALER, 2,
	(const unsigned long[2]) {MEDIA_PAD_FL_SINK,
	MEDIA_PAD_FL_SOURCE},
	&vimc_sca_ops);
	if (ret) {
	kfree(vsca);
	return ret;
	}

	vsca->ved.process_frame = vimc_sca_process_frame;
	dev_set_drvdata(comp, &vsca->ved);
	vsca->dev = comp;

	/* Initialize the frame format */
	vsca->sink_fmt = sink_fmt_default;

	return 0;
	}

	static const struct component_ops vimc_sca_comp_ops = {
	.bind = vimc_sca_comp_bind,
	.unbind = vimc_sca_comp_unbind,
	};

	static int vimc_sca_probe(struct platform_device *pdev)
	{
	return component_add(&pdev->dev, &vimc_sca_comp_ops);
	}

	static int vimc_sca_remove(struct platform_device *pdev)
	{
	component_del(&pdev->dev, &vimc_sca_comp_ops);

	return 0;
	}

	static const struct platform_device_id vimc_sca_driver_ids[] = {
	{
	.name = VIMC_SCA_DRV_NAME,
	},
	{ }
	};

	static struct platform_driver vimc_sca_pdrv = {
	.probe = vimc_sca_probe,
	.remove = vimc_sca_remove,
	.id_table = vimc_sca_driver_ids,
	.driver = {
	.name = VIMC_SCA_DRV_NAME,
	},
	};

	module_platform_driver(vimc_sca_pdrv);

	MODULE_DEVICE_TABLE(platform, vimc_sca_driver_ids);

	MODULE_DESCRIPTION("Virtual Media Controller Driver (VIMC) Scaler");
	MODULE_AUTHOR("Helen Mae Koike Fornazier <helen.fornazier@gmail.com>");
	MODULE_LICENSE("GPL");