// SPDX-License-Identifier: GPL-2.0
/*
 * Rockchip MIPI CSI2 DPHY driver
 *
 * Copyright (C) 2022 Rockchip Electronics Co., Ltd.
 */

#include <linux/clk.h>
#include <linux/delay.h>
#include <linux/io.h>
#include <linux/module.h>
#include <linux/of.h>
#include <linux/of_graph.h>
#include <linux/of_platform.h>
#include <linux/platform_device.h>
#include <linux/pm_runtime.h>
#include <linux/regmap.h>
#include <linux/mfd/syscon.h>
#include <media/media-entity.h>
#include <media/v4l2-ctrls.h>
#include <media/v4l2-fwnode.h>
#include <media/v4l2-subdev.h>
#include <media/v4l2-device.h>
#include "phy-rockchip-csi2-dphy-common.h"

struct sensor_async_subdev {
    struct v4l2_async_subdev asd;
    struct v4l2_mbus_config mbus;
    int lanes;
};

static LIST_HEAD(csi2dphy_device_list);

static inline struct csi2_dphy *to_csi2_dphy(struct v4l2_subdev *subdev)
{
    return container_of(subdev, struct csi2_dphy, sd);
}

static struct v4l2_subdev *get_remote_sensor(struct v4l2_subdev *sd)
{
    struct media_pad *local, *remote;
    struct media_entity *sensor_me;

    local = &sd->entity.pads[CSI2_DPHY_RX_PAD_SINK];
    remote = media_entity_remote_pad(local);
    if (!remote) {
        v4l2_warn(sd, "No link between dphy and sensor\n");
        return NULL;
    }

    sensor_me = media_entity_remote_pad(local)->entity;
    return media_entity_to_v4l2_subdev(sensor_me);
}

static struct csi2_sensor *sd_to_sensor(struct csi2_dphy *dphy, struct v4l2_subdev *sd)
{
    int i;

    for (i = 0; i < dphy->num_sensors; ++i) {
        if (dphy->sensors[i].sd == sd) {
            return &dphy->sensors[i];
        }
    }

    return NULL;
}

static int csi2_dphy_get_sensor_data_rate(struct v4l2_subdev *sd)
{
    struct csi2_dphy *dphy = to_csi2_dphy(sd);
    struct v4l2_subdev *sensor_sd = get_remote_sensor(sd);
    struct v4l2_ctrl *link_freq;
    struct v4l2_querymenu qm = {
        .id = V4L2_CID_LINK_FREQ,
    };
    int ret;

    link_freq = v4l2_ctrl_find(sensor_sd->ctrl_handler, V4L2_CID_LINK_FREQ);
    if (!link_freq) {
        v4l2_warn(sd, "No pixel rate control in subdev\n");
        return -EPIPE;
    }

    qm.index = v4l2_ctrl_g_ctrl(link_freq);
    ret = v4l2_querymenu(sensor_sd->ctrl_handler, &qm);
    if (ret < 0) {
        v4l2_err(sd, "Failed to get menu item\n");
        return ret;
    }

    if (!qm.value) {
        v4l2_err(sd, "Invalid link_freq\n");
        return -EINVAL;
    }
    dphy->data_rate_mbps = qm.value * 0x02;
    do_div(dphy->data_rate_mbps, 0x3E8 * 0x3E8);
    v4l2_info(sd, "dphy%d, data_rate_mbps %lld\n", dphy->phy_index, dphy->data_rate_mbps);
    return 0;
}

static int csi2_dphy_update_sensor_mbus(struct v4l2_subdev *sd)
{
    struct csi2_dphy *dphy = to_csi2_dphy(sd);
    struct v4l2_subdev *sensor_sd = get_remote_sensor(sd);
    struct csi2_sensor *sensor = sd_to_sensor(dphy, sensor_sd);
    struct v4l2_mbus_config mbus;
    int ret;

    ret = v4l2_subdev_call(sensor_sd, pad, get_mbus_config, 0, &mbus);
    if (ret) {
        return ret;
    }

    sensor->mbus = mbus;
    switch (mbus.flags & V4L2_MBUS_CSI2_LANES) {
        case V4L2_MBUS_CSI2_1_LANE:
            sensor->lanes = 1;
            break;
        case V4L2_MBUS_CSI2_2_LANE:
            sensor->lanes = 0x02;
            break;
        case V4L2_MBUS_CSI2_3_LANE:
            sensor->lanes = 0x03;
            break;
        case V4L2_MBUS_CSI2_4_LANE:
            sensor->lanes = 0x04;
            break;
        default:
            return -EINVAL;
    }

    return 0;
}

static int csi2_dphy_s_stream_start(struct v4l2_subdev *sd)
{
    struct csi2_dphy *dphy = to_csi2_dphy(sd);
    struct csi2_dphy_hw *hw = dphy->dphy_hw;
    int ret = 0;

    if (dphy->is_streaming) {
        return 0;
    }

    ret = csi2_dphy_get_sensor_data_rate(sd);
    if (ret < 0) {
        return ret;
    }

    csi2_dphy_update_sensor_mbus(sd);

    if (hw->stream_on) {
        hw->stream_on(dphy, sd);
    }

    dphy->is_streaming = true;

    return 0;
}

static int csi2_dphy_s_stream_stop(struct v4l2_subdev *sd)
{
    struct csi2_dphy *dphy = to_csi2_dphy(sd);
    struct csi2_dphy_hw *hw = dphy->dphy_hw;

    if (!dphy->is_streaming) {
        return 0;
    }

    if (hw->stream_off) {
        hw->stream_off(dphy, sd);
    }

    dphy->is_streaming = false;

    dev_info(dphy->dev, "%s stream stop, dphy%d\n", __func__, dphy->phy_index);

    return 0;
}

static int csi2_dphy_s_stream(struct v4l2_subdev *sd, int on)
{
    struct csi2_dphy *dphy = to_csi2_dphy(sd);
    int ret = 0;

    mutex_lock(&dphy->mutex);
    if (on) {
        ret = csi2_dphy_s_stream_start(sd);
    } else {
        ret = csi2_dphy_s_stream_stop(sd);
    }
    mutex_unlock(&dphy->mutex);

    dev_info(dphy->dev, "%s stream on:%d, dphy%d\n", __func__, on, dphy->phy_index);

    return ret;
}

static int csi2_dphy_g_frame_interval(struct v4l2_subdev *sd, struct v4l2_subdev_frame_interval *fi)
{
    struct v4l2_subdev *sensor = get_remote_sensor(sd);

    if (sensor) {
        return v4l2_subdev_call(sensor, video, g_frame_interval, fi);
    }

    return -EINVAL;
}

static int csi2_dphy_g_mbus_config(struct v4l2_subdev *sd, unsigned int pad_id, struct v4l2_mbus_config *config)
{
    struct csi2_dphy *dphy = to_csi2_dphy(sd);
    struct v4l2_subdev *sensor_sd = get_remote_sensor(sd);
    struct csi2_sensor *sensor;

    if (!sensor_sd) {
        return -ENODEV;
    }
    sensor = sd_to_sensor(dphy, sensor_sd);
    csi2_dphy_update_sensor_mbus(sd);
    *config = sensor->mbus;

    return 0;
}

static int csi2_dphy_s_power(struct v4l2_subdev *sd, int on)
{
    struct csi2_dphy *dphy = to_csi2_dphy(sd);

    if (on) {
        return pm_runtime_get_sync(dphy->dev);
    } else {
        return pm_runtime_put(dphy->dev);
    }
}

static __maybe_unused int csi2_dphy_runtime_suspend(struct device *dev)
{
    struct media_entity *me = dev_get_drvdata(dev);
    struct v4l2_subdev *sd = media_entity_to_v4l2_subdev(me);
    struct csi2_dphy *dphy = to_csi2_dphy(sd);
    struct csi2_dphy_hw *hw = dphy->dphy_hw;

    if (hw) {
        clk_bulk_disable_unprepare(hw->num_clks, hw->clks_bulk);
    }

    return 0;
}

static __maybe_unused int csi2_dphy_runtime_resume(struct device *dev)
{
    struct media_entity *me = dev_get_drvdata(dev);
    struct v4l2_subdev *sd = media_entity_to_v4l2_subdev(me);
    struct csi2_dphy *dphy = to_csi2_dphy(sd);
    struct csi2_dphy_hw *hw = dphy->dphy_hw;
    int ret;

    if (hw) {
        ret = clk_bulk_prepare_enable(hw->num_clks, hw->clks_bulk);
        if (ret) {
            dev_err(hw->dev, "failed to enable clks\n");
            return ret;
        }
    }

    return 0;
}

/* dphy accepts all fmt/size from sensor */
static int csi2_dphy_get_set_fmt(struct v4l2_subdev *sd, struct v4l2_subdev_pad_config *cfg,
                                 struct v4l2_subdev_format *fmt)
{
    struct csi2_dphy *dphy = to_csi2_dphy(sd);
    struct v4l2_subdev *sensor_sd = get_remote_sensor(sd);
    struct csi2_sensor *sensor = sd_to_sensor(dphy, sensor_sd);
    int ret;
    /*
     * Do not allow format changes and just relay whatever
     * set currently in the sensor.
     */
    if (!sensor_sd) {
        return -ENODEV;
    }
    ret = v4l2_subdev_call(sensor_sd, pad, get_fmt, NULL, fmt);
    if (!ret && fmt->pad == 0) {
        sensor->format = fmt->format;
    }
    return ret;
}

static int csi2_dphy_get_selection(struct v4l2_subdev *sd, struct v4l2_subdev_pad_config *cfg,
                                   struct v4l2_subdev_selection *sel)
{
    struct v4l2_subdev *sensor = get_remote_sensor(sd);

    return v4l2_subdev_call(sensor, pad, get_selection, NULL, sel);
}

static const struct v4l2_subdev_core_ops csi2_dphy_core_ops = {
    .s_power = csi2_dphy_s_power,
};

static const struct v4l2_subdev_video_ops csi2_dphy_video_ops = {
    .g_frame_interval = csi2_dphy_g_frame_interval,
    .s_stream = csi2_dphy_s_stream,
};

static const struct v4l2_subdev_pad_ops csi2_dphy_subdev_pad_ops = {
    .set_fmt = csi2_dphy_get_set_fmt,
    .get_fmt = csi2_dphy_get_set_fmt,
    .get_selection = csi2_dphy_get_selection,
    .get_mbus_config = csi2_dphy_g_mbus_config,
};

static const struct v4l2_subdev_ops csi2_dphy_subdev_ops = {
    .core = &csi2_dphy_core_ops,
    .video = &csi2_dphy_video_ops,
    .pad = &csi2_dphy_subdev_pad_ops,
};

/* The .bound() notifier callback when a match is found */
static int rockchip_csi2_dphy_notifier_bound(struct v4l2_async_notifier *notifier, struct v4l2_subdev *sd,
                                             struct v4l2_async_subdev *asd)
{
    struct csi2_dphy *dphy = container_of(notifier, struct csi2_dphy, notifier);
    struct sensor_async_subdev *s_asd = container_of(asd, struct sensor_async_subdev, asd);
    struct csi2_sensor *sensor;
    unsigned int pad, ret;

    if (dphy->num_sensors == ARRAY_SIZE(dphy->sensors)) {
        return -EBUSY;
    }

    sensor = &dphy->sensors[dphy->num_sensors++];
    sensor->lanes = s_asd->lanes;
    sensor->mbus = s_asd->mbus;
    sensor->sd = sd;

    dev_info(dphy->dev, "dphy%d matches %s:bus type %d\n", dphy->phy_index, sd->name, s_asd->mbus.type);

    for (pad = 0; pad < sensor->sd->entity.num_pads; pad++) {
        if (sensor->sd->entity.pads[pad].flags & MEDIA_PAD_FL_SOURCE) {
            break;
        }
    }

    if (pad == sensor->sd->entity.num_pads) {
        dev_err(dphy->dev, "failed to find src pad for %s\n", sensor->sd->name);

        return -ENXIO;
    }

    ret = media_create_pad_link(&sensor->sd->entity, pad, &dphy->sd.entity, CSI2_DPHY_RX_PAD_SINK,
                                dphy->num_sensors != 1 ? 0 : MEDIA_LNK_FL_ENABLED);
    if (ret) {
        dev_err(dphy->dev, "failed to create link for %s\n", sensor->sd->name);
        return ret;
    }

    return 0;
}

/* The .unbind callback */
static void rockchip_csi2_dphy_notifier_unbind(struct v4l2_async_notifier *notifier, struct v4l2_subdev *sd,
                                               struct v4l2_async_subdev *asd)
{
    struct csi2_dphy *dphy = container_of(notifier, struct csi2_dphy, notifier);
    struct csi2_sensor *sensor = sd_to_sensor(dphy, sd);

    sensor->sd = NULL;
}

static const struct v4l2_async_notifier_operations rockchip_csi2_dphy_async_ops = {
    .bound = rockchip_csi2_dphy_notifier_bound,
    .unbind = rockchip_csi2_dphy_notifier_unbind,
};

static int rockchip_csi2_dphy_fwnode_parse(struct device *dev, struct v4l2_fwnode_endpoint *vep,
                                           struct v4l2_async_subdev *asd)
{
    struct sensor_async_subdev *s_asd = container_of(asd, struct sensor_async_subdev, asd);
    struct v4l2_mbus_config *config = &s_asd->mbus;

    if (vep->base.port != 0) {
        dev_err(dev, "The PHY has only port 0\n");
        return -EINVAL;
    }

    if (vep->bus_type == V4L2_MBUS_CSI2_DPHY) {
        config->type = V4L2_MBUS_CSI2_DPHY;
        config->flags = vep->bus.mipi_csi2.flags;
        s_asd->lanes = vep->bus.mipi_csi2.num_data_lanes;
    } else {
        dev_err(dev, "Only CSI2 type is currently supported\n");
        return -EINVAL;
    }

    switch (s_asd->lanes) {
        case 1:
            config->flags |= V4L2_MBUS_CSI2_1_LANE;
            break;
        case 0x02:
            config->flags |= V4L2_MBUS_CSI2_2_LANE;
            break;
        case 0x03:
            config->flags |= V4L2_MBUS_CSI2_3_LANE;
            break;
        case 0x04:
            config->flags |= V4L2_MBUS_CSI2_4_LANE;
            break;
        default:
            return -EINVAL;
    }

    return 0;
}

static int rockchip_csi2dphy_media_init(struct csi2_dphy *dphy)
{
    int ret;

    dphy->pads[CSI2_DPHY_RX_PAD_SOURCE].flags = MEDIA_PAD_FL_SOURCE | MEDIA_PAD_FL_MUST_CONNECT;
    dphy->pads[CSI2_DPHY_RX_PAD_SINK].flags = MEDIA_PAD_FL_SINK | MEDIA_PAD_FL_MUST_CONNECT;
    dphy->sd.entity.function = MEDIA_ENT_F_VID_IF_BRIDGE;
    ret = media_entity_pads_init(&dphy->sd.entity, CSI2_DPHY_RX_PADS_NUM, dphy->pads);
    if (ret < 0) {
        return ret;
    }

    v4l2_async_notifier_init(&dphy->notifier);

    ret = v4l2_async_notifier_parse_fwnode_endpoints_by_port(
        dphy->dev, &dphy->notifier, sizeof(struct sensor_async_subdev), 0, rockchip_csi2_dphy_fwnode_parse);
    if (ret < 0) {
        return ret;
    }

    dphy->sd.subdev_notifier = &dphy->notifier;
    dphy->notifier.ops = &rockchip_csi2_dphy_async_ops;
    ret = v4l2_async_subdev_notifier_register(&dphy->sd, &dphy->notifier);
    if (ret) {
        dev_err(dphy->dev, "failed to register async notifier : %d\n", ret);
        v4l2_async_notifier_cleanup(&dphy->notifier);
        return ret;
    }

    return v4l2_async_register_subdev(&dphy->sd);
}

static int rockchip_csi2_dphy_attach_hw(struct csi2_dphy *dphy)
{
    struct platform_device *plat_dev;
    struct device *dev = dphy->dev;
    struct csi2_dphy_hw *dphy_hw;
    struct device_node *np;
    enum csi2_dphy_lane_mode target_mode;
    int i;

    if (dphy->phy_index % 3 == 0) {
        target_mode = LANE_MODE_FULL;
    } else {
        target_mode = LANE_MODE_SPLIT;
    }

    np = of_parse_phandle(dev->of_node, "rockchip,hw", 0);
    if (!np || !of_device_is_available(np)) {
        dev_err(dphy->dev, "failed to get dphy%d hw node\n", dphy->phy_index);
        return -ENODEV;
    }

    plat_dev = of_find_device_by_node(np);
    of_node_put(np);
    if (!plat_dev) {
        dev_err(dphy->dev, "failed to get dphy%d hw from node\n", dphy->phy_index);
        return -ENODEV;
    }

    dphy_hw = platform_get_drvdata(plat_dev);
    if (!dphy_hw) {
        dev_err(dphy->dev, "failed attach dphy%d hw\n", dphy->phy_index);
        return -EINVAL;
    }

    if (dphy_hw->lane_mode == LANE_MODE_UNDEF) {
        dphy_hw->lane_mode = target_mode;
    } else {
        struct csi2_dphy *phy = dphy_hw->dphy_dev[0];

        for (i = 0; i < dphy_hw->dphy_dev_num; i++) {
            if (dphy_hw->dphy_dev[i]->lane_mode == dphy_hw->lane_mode) {
                phy = dphy_hw->dphy_dev[i];
                break;
            }
        }

        if (target_mode != dphy_hw->lane_mode) {
            dev_err(dphy->dev, "Err:csi2 dphy hw has been set as %s mode by phy%d, target mode is:%s\n",
                    dphy_hw->lane_mode == LANE_MODE_FULL ? "full" : "split", phy->phy_index,
                    target_mode == LANE_MODE_FULL ? "full" : "split");
            return -ENODEV;
        }
    }

    dphy_hw->dphy_dev[dphy_hw->dphy_dev_num] = dphy;
    dphy_hw->dphy_dev_num++;
    dphy->dphy_hw = dphy_hw;

    return 0;
}

static int rockchip_csi2_dphy_detach_hw(struct csi2_dphy *dphy)
{
    struct csi2_dphy_hw *dphy_hw = dphy->dphy_hw;
    struct csi2_dphy *csi2_dphy = NULL;
    int i;

    for (i = 0; i < dphy_hw->dphy_dev_num; i++) {
        csi2_dphy = dphy_hw->dphy_dev[i];
        if (csi2_dphy && csi2_dphy->phy_index == dphy->phy_index) {
            dphy_hw->dphy_dev[i] = NULL;
            dphy_hw->dphy_dev_num--;
            break;
        }
    }

    return 0;
}

static struct dphy_drv_data r3568_dphy_drv_data = {
    .dev_name = "csi2dphy",
};

static struct dphy_drv_data r3588_dcphy_drv_data = {
    .dev_name = "csi2dcphy",
};

static const struct of_device_id rockchip_csi2_dphy_match_id[] = {{
    .compatible = "rockchip,rk3568-csi2-dphy",
    .data = &r3568_dphy_drv_data,
}, {
    .compatible = "rockchip,rk3588-csi2-dcphy",
    .data = &r3588_dcphy_drv_data,
}, {
}};
MODULE_DEVICE_TABLE(of, rockchip_csi2_dphy_match_id);

static int rockchip_csi2_dphy_probe(struct platform_device *pdev)
{
    struct device *dev = &pdev->dev;
    const struct of_device_id *of_id;
    struct csi2_dphy *csi2dphy;
    struct v4l2_subdev *sd;
    const struct dphy_drv_data *drv_data;
    int ret;

    csi2dphy = devm_kzalloc(dev, sizeof(*csi2dphy), GFP_KERNEL);
    if (!csi2dphy) {
        return -ENOMEM;
    }
    csi2dphy->dev = dev;

    of_id = of_match_device(rockchip_csi2_dphy_match_id, dev);
    if (!of_id) {
        return -EINVAL;
    }
    drv_data = of_id->data;
    csi2dphy->drv_data = drv_data;
    csi2dphy->phy_index = of_alias_get_id(dev->of_node, drv_data->dev_name);
    if (csi2dphy->phy_index < 0 || csi2dphy->phy_index >= PHY_MAX) {
        csi2dphy->phy_index = 0;
    }
    ret = rockchip_csi2_dphy_attach_hw(csi2dphy);
    if (ret) {
        dev_err(dev, "csi2 dphy hw can't be attached, register dphy%d failed!\n", csi2dphy->phy_index);
        return -ENODEV;
    }

    sd = &csi2dphy->sd;
    mutex_init(&csi2dphy->mutex);
    v4l2_subdev_init(sd, &csi2_dphy_subdev_ops);
    sd->flags |= V4L2_SUBDEV_FL_HAS_DEVNODE;
    snprintf(sd->name, sizeof(sd->name), "rockchip-csi2-dphy%d", csi2dphy->phy_index);
    sd->dev = dev;

    platform_set_drvdata(pdev, &sd->entity);

    ret = rockchip_csi2dphy_media_init(csi2dphy);
    if (ret < 0) {
        goto detach_hw;
    }

    pm_runtime_enable(&pdev->dev);

    dev_info(dev, "csi2 dphy%d probe successfully!\n", csi2dphy->phy_index);

    return 0;

detach_hw:
    mutex_destroy(&csi2dphy->mutex);
    rockchip_csi2_dphy_detach_hw(csi2dphy);

    return 0;
}

static int rockchip_csi2_dphy_remove(struct platform_device *pdev)
{
    struct media_entity *me = platform_get_drvdata(pdev);
    struct v4l2_subdev *sd = media_entity_to_v4l2_subdev(me);
    struct csi2_dphy *dphy = to_csi2_dphy(sd);

    media_entity_cleanup(&sd->entity);

    pm_runtime_disable(&pdev->dev);
    mutex_destroy(&dphy->mutex);
    return 0;
}

static const struct dev_pm_ops rockchip_csi2_dphy_pm_ops = {
    SET_RUNTIME_PM_OPS(csi2_dphy_runtime_suspend, csi2_dphy_runtime_resume, NULL)};

struct platform_driver rockchip_csi2_dphy_driver = {
    .probe = rockchip_csi2_dphy_probe,
    .remove = rockchip_csi2_dphy_remove,
    .driver =
        {
            .name = "rockchip-csi2-dphy",
            .pm = &rockchip_csi2_dphy_pm_ops,
            .of_match_table = rockchip_csi2_dphy_match_id,
        },
};
module_platform_driver(rockchip_csi2_dphy_driver);

MODULE_AUTHOR("Rockchip Camera/ISP team");
MODULE_DESCRIPTION("Rockchip MIPI CSI2 DPHY driver");
MODULE_LICENSE("GPL v2");