// SPDX-License-Identifier: GPL-2.0+
/*
 * Driver for Analog Devices ADV748X CSI-2 Transmitter
 *
 * Copyright (C) 2017 Renesas Electronics Corp.
 */

#include <linux/module.h>

#include <media/v4l2-ctrls.h>
#include <media/v4l2-device.h>
#include <media/v4l2-ioctl.h>

#include "adv748x.h"

static const unsigned int adv748x_csi2_txa_fmts[] = {
        MEDIA_BUS_FMT_UYVY8_1X16,
        MEDIA_BUS_FMT_RGB888_1X24,
};

static const unsigned int adv748x_csi2_txb_fmts[] = {
        MEDIA_BUS_FMT_UYVY8_1X16,
};

int adv748x_csi2_set_virtual_channel(struct adv748x_csi2 *tx, unsigned int vc)
{
        return tx_write(tx, ADV748X_CSI_VC_REF, vc << ADV748X_CSI_VC_REF_SHIFT);
}

/**
 * adv748x_csi2_register_link : Register and link internal entities
 *
 * @tx: CSI2 private entity
 * @v4l2_dev: Video registration device
 * @src: Source subdevice to establish link
 * @src_pad: Pad number of source to link to this @tx
 * @enable: Link enabled flag
 *
 * Ensure that the subdevice is registered against the v4l2_device, and link the
 * source pad to the sink pad of the CSI2 bus entity.
 */
static int adv748x_csi2_register_link(struct adv748x_csi2 *tx,
                                      struct v4l2_device *v4l2_dev,
                                      struct v4l2_subdev *src,
                                      unsigned int src_pad,
                                      bool enable)
{
        int ret;

        if (!src->v4l2_dev) {
                ret = v4l2_device_register_subdev(v4l2_dev, src);
                if (ret)
                        return ret;
        }

        ret = media_create_pad_link(&src->entity, src_pad,
                                    &tx->sd.entity, ADV748X_CSI2_SINK,
                                    enable ? MEDIA_LNK_FL_ENABLED : 0);
        if (ret)
                return ret;

        if (enable)
                tx->src = src;

        return 0;
}

/* -----------------------------------------------------------------------------
 * v4l2_subdev_internal_ops
 */

static int adv748x_csi2_init_state(struct v4l2_subdev *sd,
                                   struct v4l2_subdev_state *state)
{
        static const struct v4l2_mbus_framefmt adv748x_csi2_default_fmt = {
                .width          = 1280,
                .height         = 720,
                .code           = MEDIA_BUS_FMT_UYVY8_1X16,
                .colorspace     = V4L2_COLORSPACE_SRGB,
                .field          = V4L2_FIELD_NONE,
                .ycbcr_enc      = V4L2_YCBCR_ENC_DEFAULT,
                .quantization   = V4L2_QUANTIZATION_DEFAULT,
                .xfer_func      = V4L2_XFER_FUNC_DEFAULT,
        };
        struct v4l2_mbus_framefmt *fmt;

        fmt = v4l2_subdev_state_get_format(state, ADV748X_CSI2_SINK);
        *fmt = adv748x_csi2_default_fmt;

        fmt = v4l2_subdev_state_get_format(state, ADV748X_CSI2_SOURCE);
        *fmt = adv748x_csi2_default_fmt;

        return 0;
}

/*
 * We use the internal registered operation to be able to ensure that our
 * incremental subdevices (not connected in the forward path) can be registered
 * against the resulting video path and media device.
 */

static int adv748x_csi2_registered(struct v4l2_subdev *sd)
{
        struct adv748x_csi2 *tx = adv748x_sd_to_csi2(sd);
        struct adv748x_state *state = tx->state;
        int ret;

        adv_dbg(state, "Registered %s (%s)", is_txa(tx) ? "TXA":"TXB",
                        sd->name);

        /*
         * Link TXA to AFE and HDMI, and TXB to AFE only as TXB cannot output
         * HDMI.
         *
         * The HDMI->TXA link is enabled by default, as is the AFE->TXB one.
         */
        if (is_afe_enabled(state)) {
                ret = adv748x_csi2_register_link(tx, sd->v4l2_dev,
                                                 &state->afe.sd,
                                                 ADV748X_AFE_SOURCE,
                                                 is_txb(tx));
                if (ret)
                        return ret;

                /* TXB can output AFE signals only. */
                if (is_txb(tx))
                        state->afe.tx = tx;
        }

        /* Register link to HDMI for TXA only. */
        if (is_txb(tx) || !is_hdmi_enabled(state))
                return 0;

        ret = adv748x_csi2_register_link(tx, sd->v4l2_dev, &state->hdmi.sd,
                                         ADV748X_HDMI_SOURCE, true);
        if (ret)
                return ret;

        /* The default HDMI output is TXA. */
        state->hdmi.tx = tx;

        return 0;
}

static const struct v4l2_subdev_internal_ops adv748x_csi2_internal_ops = {
        .init_state = adv748x_csi2_init_state,
        .registered = adv748x_csi2_registered,
};

/* -----------------------------------------------------------------------------
 * v4l2_subdev_video_ops
 */

static int adv748x_csi2_s_stream(struct v4l2_subdev *sd, int enable)
{
        struct adv748x_csi2 *tx = adv748x_sd_to_csi2(sd);
        struct v4l2_subdev *src;

        src = adv748x_get_remote_sd(&tx->pads[ADV748X_CSI2_SINK]);
        if (!src)
                return -EPIPE;

        return v4l2_subdev_call(src, video, s_stream, enable);
}

static const struct v4l2_subdev_video_ops adv748x_csi2_video_ops = {
        .s_stream = adv748x_csi2_s_stream,
};

/* -----------------------------------------------------------------------------
 * v4l2_subdev_pad_ops
 *
 * The CSI2 bus pads are ignorant to the data sizes or formats.
 * But we must support setting the pad formats for format propagation.
 */

static int adv748x_csi2_enum_mbus_code(struct v4l2_subdev *sd,
                                       struct v4l2_subdev_state *sd_state,
                                       struct v4l2_subdev_mbus_code_enum *code)
{
        struct adv748x_csi2 *tx = adv748x_sd_to_csi2(sd);
        const unsigned int *codes = is_txa(tx) ?
                                    adv748x_csi2_txa_fmts :
                                    adv748x_csi2_txb_fmts;
        size_t num_fmts = is_txa(tx) ? ARRAY_SIZE(adv748x_csi2_txa_fmts)
                                     : ARRAY_SIZE(adv748x_csi2_txb_fmts);

        /*
         * The format available on the source pad is the one applied on the sink
         * pad.
         */
        if (code->pad == ADV748X_CSI2_SOURCE) {
                struct v4l2_mbus_framefmt *fmt;

                if (code->index)
                        return -EINVAL;

                fmt = v4l2_subdev_state_get_format(sd_state, ADV748X_CSI2_SINK);
                code->code = fmt->code;

                return 0;
        }

        if (code->index >= num_fmts)
                return -EINVAL;

        code->code = codes[code->index];

        return 0;
}

static bool adv748x_csi2_is_fmt_supported(struct adv748x_csi2 *tx, u32 code)
{
        const unsigned int *codes = is_txa(tx) ?
                                    adv748x_csi2_txa_fmts :
                                    adv748x_csi2_txb_fmts;
        size_t num_fmts = is_txa(tx) ? ARRAY_SIZE(adv748x_csi2_txa_fmts)
                                     : ARRAY_SIZE(adv748x_csi2_txb_fmts);

        for (unsigned int i = 0; i < num_fmts; i++) {
                if (codes[i] == code)
                        return true;
        }

        return false;
}

static int adv748x_csi2_set_format(struct v4l2_subdev *sd,
                                   struct v4l2_subdev_state *sd_state,
                                   struct v4l2_subdev_format *sdformat)
{
        struct adv748x_csi2 *tx = adv748x_sd_to_csi2(sd);
        struct v4l2_mbus_framefmt *mbusformat;

        if (sdformat->pad == ADV748X_CSI2_SOURCE)
                return v4l2_subdev_get_fmt(sd, sd_state, sdformat);

        /*
         * Make sure the format is supported, if not default it to
         * UYVY8 as it's supported by both TXes.
         */
        if (!adv748x_csi2_is_fmt_supported(tx, sdformat->format.code))
                sdformat->format.code = MEDIA_BUS_FMT_UYVY8_1X16;

        mbusformat = v4l2_subdev_state_get_format(sd_state, sdformat->pad);
        *mbusformat = sdformat->format;

        /* Propagate format to the source pad. */
        mbusformat = v4l2_subdev_state_get_format(sd_state, ADV748X_CSI2_SOURCE);
        *mbusformat = sdformat->format;

        return 0;
}

static int adv748x_csi2_get_mbus_config(struct v4l2_subdev *sd, unsigned int pad,
                                        struct v4l2_mbus_config *config)
{
        struct adv748x_csi2 *tx = adv748x_sd_to_csi2(sd);

        if (pad != ADV748X_CSI2_SOURCE)
                return -EINVAL;

        config->type = V4L2_MBUS_CSI2_DPHY;
        config->bus.mipi_csi2.num_data_lanes = tx->active_lanes;

        return 0;
}

static const struct v4l2_subdev_pad_ops adv748x_csi2_pad_ops = {
        .enum_mbus_code = adv748x_csi2_enum_mbus_code,
        .get_fmt = v4l2_subdev_get_fmt,
        .set_fmt = adv748x_csi2_set_format,
        .get_mbus_config = adv748x_csi2_get_mbus_config,
};

/* -----------------------------------------------------------------------------
 * v4l2_subdev_ops
 */

static const struct v4l2_subdev_ops adv748x_csi2_ops = {
        .video = &adv748x_csi2_video_ops,
        .pad = &adv748x_csi2_pad_ops,
};

/* -----------------------------------------------------------------------------
 * Subdev module and controls
 */

int adv748x_csi2_set_pixelrate(struct v4l2_subdev *sd, s64 rate)
{
        struct adv748x_csi2 *tx = adv748x_sd_to_csi2(sd);

        if (!tx->pixel_rate)
                return -EINVAL;

        return v4l2_ctrl_s_ctrl_int64(tx->pixel_rate, rate);
}

static int adv748x_csi2_s_ctrl(struct v4l2_ctrl *ctrl)
{
        switch (ctrl->id) {
        case V4L2_CID_PIXEL_RATE:
                return 0;
        default:
                return -EINVAL;
        }
}

static const struct v4l2_ctrl_ops adv748x_csi2_ctrl_ops = {
        .s_ctrl = adv748x_csi2_s_ctrl,
};

static int adv748x_csi2_init_controls(struct adv748x_csi2 *tx)
{

        v4l2_ctrl_handler_init(&tx->ctrl_hdl, 1);

        tx->pixel_rate = v4l2_ctrl_new_std(&tx->ctrl_hdl,
                                           &adv748x_csi2_ctrl_ops,
                                           V4L2_CID_PIXEL_RATE, 1, INT_MAX,
                                           1, 1);

        tx->sd.ctrl_handler = &tx->ctrl_hdl;
        if (tx->ctrl_hdl.error) {
                v4l2_ctrl_handler_free(&tx->ctrl_hdl);
                return tx->ctrl_hdl.error;
        }

        return v4l2_ctrl_handler_setup(&tx->ctrl_hdl);
}

int adv748x_csi2_init(struct adv748x_state *state, struct adv748x_csi2 *tx)
{
        int ret;

        if (!is_tx_enabled(tx))
                return 0;

        adv748x_subdev_init(&tx->sd, state, &adv748x_csi2_ops,
                            MEDIA_ENT_F_VID_IF_BRIDGE,
                            is_txa(tx) ? "txa" : "txb");

        /* Register internal ops for incremental subdev registration */
        tx->sd.internal_ops = &adv748x_csi2_internal_ops;

        tx->pads[ADV748X_CSI2_SINK].flags = MEDIA_PAD_FL_SINK;
        tx->pads[ADV748X_CSI2_SOURCE].flags = MEDIA_PAD_FL_SOURCE;

        ret = media_entity_pads_init(&tx->sd.entity, ADV748X_CSI2_NR_PADS,
                                     tx->pads);
        if (ret)
                return ret;

        ret = v4l2_async_subdev_endpoint_add(&tx->sd,
                                             of_fwnode_handle(state->endpoints[tx->port]));
        if (ret)
                goto err_free_media;

        ret = adv748x_csi2_init_controls(tx);
        if (ret)
                goto err_cleanup_subdev;

        tx->sd.state_lock = &state->mutex;
        ret = v4l2_subdev_init_finalize(&tx->sd);
        if (ret)
                goto err_free_ctrl;

        ret = v4l2_async_register_subdev(&tx->sd);
        if (ret)
                goto err_free_ctrl;

        return 0;

err_free_ctrl:
        v4l2_ctrl_handler_free(&tx->ctrl_hdl);
err_cleanup_subdev:
        v4l2_subdev_cleanup(&tx->sd);
err_free_media:
        media_entity_cleanup(&tx->sd.entity);

        return ret;
}

void adv748x_csi2_cleanup(struct adv748x_csi2 *tx)
{
        if (!is_tx_enabled(tx))
                return;

        v4l2_async_unregister_subdev(&tx->sd);
        media_entity_cleanup(&tx->sd.entity);
        v4l2_ctrl_handler_free(&tx->ctrl_hdl);
        v4l2_subdev_cleanup(&tx->sd);
}