/*
 * vsp1_lut.c  --  R-Car VSP1 Look-Up Table
 *
 * 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 <linux/vsp1.h>

#include <media/v4l2-subdev.h>

#include "vsp1.h"
#include "vsp1_lut.h"

#define LUT_MIN_SIZE                            4U
#define LUT_MAX_SIZE                            8190U

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

static inline u32 vsp1_lut_read(struct vsp1_lut *lut, u32 reg)
{
        return vsp1_read(lut->entity.vsp1, reg);
}

static inline void vsp1_lut_write(struct vsp1_lut *lut, u32 reg, u32 data)
{
        vsp1_write(lut->entity.vsp1, reg, data);
}

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

static void lut_configure(struct vsp1_lut *lut, struct vsp1_lut_config *config)
{
        memcpy_toio(lut->entity.vsp1->mmio + VI6_LUT_TABLE, config->lut,
                    sizeof(config->lut));
}

static long lut_ioctl(struct v4l2_subdev *subdev, unsigned int cmd, void *arg)
{
        struct vsp1_lut *lut = to_lut(subdev);

        switch (cmd) {
        case VIDIOC_VSP1_LUT_CONFIG:
                lut_configure(lut, arg);
                return 0;

        default:
                return -ENOIOCTLCMD;
        }
}

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

static int lut_s_stream(struct v4l2_subdev *subdev, int enable)
{
        struct vsp1_lut *lut = to_lut(subdev);

        if (!enable)
                return 0;

        vsp1_lut_write(lut, VI6_LUT_CTRL, VI6_LUT_CTRL_EN);

        return 0;
}

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

static int lut_enum_mbus_code(struct v4l2_subdev *subdev,
                              struct v4l2_subdev_pad_config *cfg,
                              struct v4l2_subdev_mbus_code_enum *code)
{
        static const unsigned int codes[] = {
                MEDIA_BUS_FMT_ARGB8888_1X32,
                MEDIA_BUS_FMT_AHSV8888_1X32,
                MEDIA_BUS_FMT_AYUV8_1X32,
        };
        struct vsp1_lut *lut = to_lut(subdev);
        struct v4l2_mbus_framefmt *format;

        if (code->pad == LUT_PAD_SINK) {
                if (code->index >= ARRAY_SIZE(codes))
                        return -EINVAL;

                code->code = codes[code->index];
        } else {
                /* The LUT can't perform format conversion, the sink format is
                 * always identical to the source format.
                 */
                if (code->index)
                        return -EINVAL;

                format = vsp1_entity_get_pad_format(&lut->entity, cfg,
                                                    LUT_PAD_SINK, code->which);
                code->code = format->code;
        }

        return 0;
}

static int lut_enum_frame_size(struct v4l2_subdev *subdev,
                               struct v4l2_subdev_pad_config *cfg,
                               struct v4l2_subdev_frame_size_enum *fse)
{
        struct vsp1_lut *lut = to_lut(subdev);
        struct v4l2_mbus_framefmt *format;

        format = vsp1_entity_get_pad_format(&lut->entity, cfg,
                                            fse->pad, fse->which);

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

        if (fse->pad == LUT_PAD_SINK) {
                fse->min_width = LUT_MIN_SIZE;
                fse->max_width = LUT_MAX_SIZE;
                fse->min_height = LUT_MIN_SIZE;
                fse->max_height = LUT_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 lut_get_format(struct v4l2_subdev *subdev, struct v4l2_subdev_pad_config *cfg,
                          struct v4l2_subdev_format *fmt)
{
        struct vsp1_lut *lut = to_lut(subdev);

        fmt->format = *vsp1_entity_get_pad_format(&lut->entity, cfg, fmt->pad,
                                                  fmt->which);

        return 0;
}

static int lut_set_format(struct v4l2_subdev *subdev, struct v4l2_subdev_pad_config *cfg,
                          struct v4l2_subdev_format *fmt)
{
        struct vsp1_lut *lut = to_lut(subdev);
        struct v4l2_mbus_framefmt *format;

        /* Default to YUV if the requested format is not supported. */
        if (fmt->format.code != MEDIA_BUS_FMT_ARGB8888_1X32 &&
            fmt->format.code != MEDIA_BUS_FMT_AHSV8888_1X32 &&
            fmt->format.code != MEDIA_BUS_FMT_AYUV8_1X32)
                fmt->format.code = MEDIA_BUS_FMT_AYUV8_1X32;

        format = vsp1_entity_get_pad_format(&lut->entity, cfg, fmt->pad,
                                            fmt->which);

        if (fmt->pad == LUT_PAD_SOURCE) {
                /* The LUT output format can't be modified. */
                fmt->format = *format;
                return 0;
        }

        format->width = clamp_t(unsigned int, fmt->format.width,
                                LUT_MIN_SIZE, LUT_MAX_SIZE);
        format->height = clamp_t(unsigned int, fmt->format.height,
                                 LUT_MIN_SIZE, LUT_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(&lut->entity, cfg, LUT_PAD_SOURCE,
                                            fmt->which);
        *format = fmt->format;

        return 0;
}

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

static struct v4l2_subdev_core_ops lut_core_ops = {
        .ioctl = lut_ioctl,
};

static struct v4l2_subdev_video_ops lut_video_ops = {
        .s_stream = lut_s_stream,
};

static struct v4l2_subdev_pad_ops lut_pad_ops = {
        .enum_mbus_code = lut_enum_mbus_code,
        .enum_frame_size = lut_enum_frame_size,
        .get_fmt = lut_get_format,
        .set_fmt = lut_set_format,
};

static struct v4l2_subdev_ops lut_ops = {
        .core   = &lut_core_ops,
        .video  = &lut_video_ops,
        .pad    = &lut_pad_ops,
};

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

struct vsp1_lut *vsp1_lut_create(struct vsp1_device *vsp1)
{
        struct v4l2_subdev *subdev;
        struct vsp1_lut *lut;
        int ret;

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

        lut->entity.type = VSP1_ENTITY_LUT;

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

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

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

        vsp1_entity_init_formats(subdev, NULL);

        return lut;
}