/*
 * vsp1_hsit.c  --  R-Car VSP1 Hue Saturation value (Inverse) Transform
 *
 * Copyright (C) 2013 Renesas Corporation
 *
 * Contact: Laurent Pinchart (laurent.pinchart@ideasonboard.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.
 */

#include <linux/device.h>
#include <linux/gfp.h>

#include <media/v4l2-subdev.h>

#include "vsp1.h"
#include "vsp1_hsit.h"

#define HSIT_MIN_SIZE				4U
#define HSIT_MAX_SIZE				8190U

/* -----------------------------------------------------------------------------
 * Device Access
 */

static inline u32 vsp1_hsit_read(struct vsp1_hsit *hsit, u32 reg)
{
	return vsp1_read(hsit->entity.vsp1, reg);
}

static inline void vsp1_hsit_write(struct vsp1_hsit *hsit, u32 reg, u32 data)
{
	vsp1_write(hsit->entity.vsp1, reg, data);
}

/* -----------------------------------------------------------------------------
 * V4L2 Subdevice Core Operations
 */

static int hsit_s_stream(struct v4l2_subdev *subdev, int enable)
{
	struct vsp1_hsit *hsit = to_hsit(subdev);

	if (!enable)
		return 0;

	if (hsit->inverse)
		vsp1_hsit_write(hsit, VI6_HSI_CTRL, VI6_HSI_CTRL_EN);
	else
		vsp1_hsit_write(hsit, VI6_HST_CTRL, VI6_HST_CTRL_EN);

	return 0;
}

/* -----------------------------------------------------------------------------
 * V4L2 Subdevice Pad Operations
 */

static int hsit_enum_mbus_code(struct v4l2_subdev *subdev,
			       struct v4l2_subdev_fh *fh,
			       struct v4l2_subdev_mbus_code_enum *code)
{
	struct vsp1_hsit *hsit = to_hsit(subdev);

	if (code->index > 0)
		return -EINVAL;

	if ((code->pad == HSIT_PAD_SINK && !hsit->inverse) |
	    (code->pad == HSIT_PAD_SOURCE && hsit->inverse))
		code->code = V4L2_MBUS_FMT_ARGB8888_1X32;
	else
		code->code = V4L2_MBUS_FMT_AHSV8888_1X32;

	return 0;
}

static int hsit_enum_frame_size(struct v4l2_subdev *subdev,
				struct v4l2_subdev_fh *fh,
				struct v4l2_subdev_frame_size_enum *fse)
{
	struct v4l2_mbus_framefmt *format;

	format = v4l2_subdev_get_try_format(fh, fse->pad);

	if (fse->index || fse->code != format->code)
		return -EINVAL;

	if (fse->pad == HSIT_PAD_SINK) {
		fse->min_width = HSIT_MIN_SIZE;
		fse->max_width = HSIT_MAX_SIZE;
		fse->min_height = HSIT_MIN_SIZE;
		fse->max_height = HSIT_MAX_SIZE;
	} else {
		/* The size on the source pad are fixed and always identical to
		 * the size on the sink pad.
		 */
		fse->min_width = format->width;
		fse->max_width = format->width;
		fse->min_height = format->height;
		fse->max_height = format->height;
	}

	return 0;
}

static int hsit_get_format(struct v4l2_subdev *subdev,
			   struct v4l2_subdev_fh *fh,
			   struct v4l2_subdev_format *fmt)
{
	struct vsp1_hsit *hsit = to_hsit(subdev);

	fmt->format = *vsp1_entity_get_pad_format(&hsit->entity, fh, fmt->pad,
						  fmt->which);

	return 0;
}

static int hsit_set_format(struct v4l2_subdev *subdev,
			   struct v4l2_subdev_fh *fh,
			   struct v4l2_subdev_format *fmt)
{
	struct vsp1_hsit *hsit = to_hsit(subdev);
	struct v4l2_mbus_framefmt *format;

	format = vsp1_entity_get_pad_format(&hsit->entity, fh, fmt->pad,
					    fmt->which);

	if (fmt->pad == HSIT_PAD_SOURCE) {
		/* The HST and HSI output format code and resolution can't be
		 * modified.
		 */
		fmt->format = *format;
		return 0;
	}

	format->code = hsit->inverse ? V4L2_MBUS_FMT_AHSV8888_1X32
		     : V4L2_MBUS_FMT_ARGB8888_1X32;
	format->width = clamp_t(unsigned int, fmt->format.width,
				HSIT_MIN_SIZE, HSIT_MAX_SIZE);
	format->height = clamp_t(unsigned int, fmt->format.height,
				 HSIT_MIN_SIZE, HSIT_MAX_SIZE);
	format->field = V4L2_FIELD_NONE;
	format->colorspace = V4L2_COLORSPACE_SRGB;

	fmt->format = *format;

	/* Propagate the format to the source pad. */
	format = vsp1_entity_get_pad_format(&hsit->entity, fh, HSIT_PAD_SOURCE,
					    fmt->which);
	*format = fmt->format;
	format->code = hsit->inverse ? V4L2_MBUS_FMT_ARGB8888_1X32
		     : V4L2_MBUS_FMT_AHSV8888_1X32;

	return 0;
}

/* -----------------------------------------------------------------------------
 * V4L2 Subdevice Operations
 */

static struct v4l2_subdev_video_ops hsit_video_ops = {
	.s_stream = hsit_s_stream,
};

static struct v4l2_subdev_pad_ops hsit_pad_ops = {
	.enum_mbus_code = hsit_enum_mbus_code,
	.enum_frame_size = hsit_enum_frame_size,
	.get_fmt = hsit_get_format,
	.set_fmt = hsit_set_format,
};

static struct v4l2_subdev_ops hsit_ops = {
	.video	= &hsit_video_ops,
	.pad    = &hsit_pad_ops,
};

/* -----------------------------------------------------------------------------
 * Initialization and Cleanup
 */

struct vsp1_hsit *vsp1_hsit_create(struct vsp1_device *vsp1, bool inverse)
{
	struct v4l2_subdev *subdev;
	struct vsp1_hsit *hsit;
	int ret;

	hsit = devm_kzalloc(vsp1->dev, sizeof(*hsit), GFP_KERNEL);
	if (hsit == NULL)
		return ERR_PTR(-ENOMEM);

	hsit->inverse = inverse;

	if (inverse) {
		hsit->entity.type = VSP1_ENTITY_HSI;
		hsit->entity.id = VI6_DPR_NODE_HSI;
	} else {
		hsit->entity.type = VSP1_ENTITY_HST;
		hsit->entity.id = VI6_DPR_NODE_HST;
	}

	ret = vsp1_entity_init(vsp1, &hsit->entity, 2);
	if (ret < 0)
		return ERR_PTR(ret);

	/* Initialize the V4L2 subdev. */
	subdev = &hsit->entity.subdev;
	v4l2_subdev_init(subdev, &hsit_ops);

	subdev->entity.ops = &vsp1_media_ops;
	subdev->internal_ops = &vsp1_subdev_internal_ops;
	snprintf(subdev->name, sizeof(subdev->name), "%s %s",
		 dev_name(vsp1->dev), inverse ? "hsi" : "hst");
	v4l2_set_subdevdata(subdev, hsit);
	subdev->flags |= V4L2_SUBDEV_FL_HAS_DEVNODE;

	vsp1_entity_init_formats(subdev, NULL);

	return hsit;
}