// SPDX-License-Identifier: GPL-2.0-only
/*
 * Microchip Image Sensor Controller (ISC) Scaler entity support
 *
 * Copyright (C) 2022 Microchip Technology, Inc.
 *
 * Author: Eugen Hristev <eugen.hristev@microchip.com>
 *
 */

#include <media/media-device.h>
#include <media/media-entity.h>
#include <media/v4l2-device.h>
#include <media/v4l2-subdev.h>

#include "microchip-isc-regs.h"
#include "microchip-isc.h"

static void isc_scaler_prepare_fmt(struct v4l2_mbus_framefmt *framefmt)
{
        framefmt->colorspace = V4L2_COLORSPACE_SRGB;
        framefmt->field = V4L2_FIELD_NONE;
        framefmt->ycbcr_enc = V4L2_YCBCR_ENC_DEFAULT;
        framefmt->quantization = V4L2_QUANTIZATION_DEFAULT;
        framefmt->xfer_func = V4L2_XFER_FUNC_DEFAULT;
};

static int isc_scaler_get_fmt(struct v4l2_subdev *sd,
                              struct v4l2_subdev_state *sd_state,
                              struct v4l2_subdev_format *format)
{
        struct isc_device *isc = container_of(sd, struct isc_device, scaler_sd);
        struct v4l2_mbus_framefmt *v4l2_try_fmt;

        if (format->which == V4L2_SUBDEV_FORMAT_TRY) {
                v4l2_try_fmt = v4l2_subdev_state_get_format(sd_state,
                                                            format->pad);
                format->format = *v4l2_try_fmt;

                return 0;
        }

        format->format = isc->scaler_format[format->pad];

        return 0;
}

static int isc_scaler_set_fmt(struct v4l2_subdev *sd,
                              struct v4l2_subdev_state *sd_state,
                              struct v4l2_subdev_format *req_fmt)
{
        struct isc_device *isc = container_of(sd, struct isc_device, scaler_sd);
        struct v4l2_mbus_framefmt *v4l2_try_fmt;
        struct isc_format *fmt;
        unsigned int i;

        /* Source format is fixed, we cannot change it */
        if (req_fmt->pad == ISC_SCALER_PAD_SOURCE) {
                req_fmt->format = isc->scaler_format[ISC_SCALER_PAD_SOURCE];
                return 0;
        }

        /* There is no limit on the frame size on the sink pad */
        v4l_bound_align_image(&req_fmt->format.width, 16, UINT_MAX, 0,
                              &req_fmt->format.height, 16, UINT_MAX, 0, 0);

        isc_scaler_prepare_fmt(&req_fmt->format);

        fmt = isc_find_format_by_code(isc, req_fmt->format.code, &i);

        if (!fmt)
                fmt = &isc->formats_list[0];

        req_fmt->format.code = fmt->mbus_code;

        if (req_fmt->which == V4L2_SUBDEV_FORMAT_TRY) {
                v4l2_try_fmt = v4l2_subdev_state_get_format(sd_state,
                                                            req_fmt->pad);
                *v4l2_try_fmt = req_fmt->format;
                /* Trying on the sink pad makes the source pad change too */
                v4l2_try_fmt = v4l2_subdev_state_get_format(sd_state,
                                                            ISC_SCALER_PAD_SOURCE);
                *v4l2_try_fmt = req_fmt->format;

                v4l_bound_align_image(&v4l2_try_fmt->width,
                                      16, isc->max_width, 0,
                                      &v4l2_try_fmt->height,
                                      16, isc->max_height, 0, 0);
                /* if we are just trying, we are done */
                return 0;
        }

        isc->scaler_format[ISC_SCALER_PAD_SINK] = req_fmt->format;

        /* The source pad is the same as the sink, but we have to crop it */
        isc->scaler_format[ISC_SCALER_PAD_SOURCE] =
                isc->scaler_format[ISC_SCALER_PAD_SINK];
        v4l_bound_align_image
                (&isc->scaler_format[ISC_SCALER_PAD_SOURCE].width, 16,
                 isc->max_width, 0,
                 &isc->scaler_format[ISC_SCALER_PAD_SOURCE].height, 16,
                 isc->max_height, 0, 0);

        return 0;
}

static int isc_scaler_enum_mbus_code(struct v4l2_subdev *sd,
                                     struct v4l2_subdev_state *sd_state,
                                     struct v4l2_subdev_mbus_code_enum *code)
{
        struct isc_device *isc = container_of(sd, struct isc_device, scaler_sd);

        /*
         * All formats supported by the ISC are supported by the scaler.
         * Advertise the formats which the ISC can take as input, as the scaler
         * entity cropping is part of the PFE module (parallel front end)
         */
        if (code->index < isc->formats_list_size) {
                code->code = isc->formats_list[code->index].mbus_code;
                return 0;
        }

        return -EINVAL;
}

static int isc_scaler_g_sel(struct v4l2_subdev *sd,
                            struct v4l2_subdev_state *sd_state,
                            struct v4l2_subdev_selection *sel)
{
        struct isc_device *isc = container_of(sd, struct isc_device, scaler_sd);

        if (sel->pad == ISC_SCALER_PAD_SOURCE)
                return -EINVAL;

        if (sel->target != V4L2_SEL_TGT_CROP_BOUNDS &&
            sel->target != V4L2_SEL_TGT_CROP)
                return -EINVAL;

        sel->r.height = isc->scaler_format[ISC_SCALER_PAD_SOURCE].height;
        sel->r.width = isc->scaler_format[ISC_SCALER_PAD_SOURCE].width;

        sel->r.left = 0;
        sel->r.top = 0;

        return 0;
}

static int isc_scaler_init_state(struct v4l2_subdev *sd,
                                 struct v4l2_subdev_state *sd_state)
{
        struct v4l2_mbus_framefmt *v4l2_try_fmt =
                v4l2_subdev_state_get_format(sd_state, 0);
        struct v4l2_rect *try_crop;
        struct isc_device *isc = container_of(sd, struct isc_device, scaler_sd);

        *v4l2_try_fmt = isc->scaler_format[ISC_SCALER_PAD_SOURCE];

        try_crop = v4l2_subdev_state_get_crop(sd_state, 0);

        try_crop->top = 0;
        try_crop->left = 0;
        try_crop->width = v4l2_try_fmt->width;
        try_crop->height = v4l2_try_fmt->height;

        return 0;
}

static const struct v4l2_subdev_pad_ops isc_scaler_pad_ops = {
        .enum_mbus_code = isc_scaler_enum_mbus_code,
        .set_fmt = isc_scaler_set_fmt,
        .get_fmt = isc_scaler_get_fmt,
        .get_selection = isc_scaler_g_sel,
};

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,
};

static const struct v4l2_subdev_internal_ops isc_scaler_internal_ops = {
        .init_state = isc_scaler_init_state,
};

int isc_scaler_init(struct isc_device *isc)
{
        int ret;

        v4l2_subdev_init(&isc->scaler_sd, &xisc_scaler_subdev_ops);
        isc->scaler_sd.internal_ops = &isc_scaler_internal_ops;

        isc->scaler_sd.owner = THIS_MODULE;
        isc->scaler_sd.dev = isc->dev;
        snprintf(isc->scaler_sd.name, sizeof(isc->scaler_sd.name),
                 "microchip_isc_scaler");

        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;

        isc_scaler_prepare_fmt(&isc->scaler_format[ISC_SCALER_PAD_SOURCE]);
        isc->scaler_format[ISC_SCALER_PAD_SOURCE].height = isc->max_height;
        isc->scaler_format[ISC_SCALER_PAD_SOURCE].width = isc->max_width;
        isc->scaler_format[ISC_SCALER_PAD_SOURCE].code =
                 isc->formats_list[0].mbus_code;

        isc->scaler_format[ISC_SCALER_PAD_SINK] =
                 isc->scaler_format[ISC_SCALER_PAD_SOURCE];

        ret = media_entity_pads_init(&isc->scaler_sd.entity,
                                     ISC_SCALER_PADS_NUM,
                                     isc->scaler_pads);
        if (ret < 0) {
                dev_err(isc->dev, "scaler sd media entity init failed\n");
                return ret;
        }

        ret = v4l2_device_register_subdev(&isc->v4l2_dev, &isc->scaler_sd);
        if (ret < 0) {
                dev_err(isc->dev, "scaler sd failed to register subdev\n");
                return ret;
        }

        return ret;
}
EXPORT_SYMBOL_GPL(isc_scaler_init);

int isc_scaler_link(struct isc_device *isc)
{
        int ret;

        ret = media_create_pad_link(&isc->current_subdev->sd->entity,
                                    isc->remote_pad, &isc->scaler_sd.entity,
                                    ISC_SCALER_PAD_SINK,
                                    MEDIA_LNK_FL_ENABLED |
                                    MEDIA_LNK_FL_IMMUTABLE);

        if (ret < 0) {
                dev_err(isc->dev, "Failed to create pad link: %s to %s\n",
                        isc->current_subdev->sd->entity.name,
                        isc->scaler_sd.entity.name);
                return ret;
        }

        dev_dbg(isc->dev, "link with %s pad: %d\n",
                isc->current_subdev->sd->name, isc->remote_pad);

        ret = media_create_pad_link(&isc->scaler_sd.entity,
                                    ISC_SCALER_PAD_SOURCE,
                                    &isc->video_dev.entity, ISC_PAD_SINK,
                                    MEDIA_LNK_FL_ENABLED |
                                    MEDIA_LNK_FL_IMMUTABLE);

        if (ret < 0) {
                dev_err(isc->dev, "Failed to create pad link: %s to %s\n",
                        isc->scaler_sd.entity.name,
                        isc->video_dev.entity.name);
                return ret;
        }

        dev_dbg(isc->dev, "link with %s pad: %d\n", isc->scaler_sd.name,
                ISC_SCALER_PAD_SOURCE);

        return ret;
}
EXPORT_SYMBOL_GPL(isc_scaler_link);