// SPDX-License-Identifier: GPL-2.0
/*
 * Elida kd35t133 3.5" MIPI-DSI panel driver
 * Copyright (C) 2020 Theobroma Systems Design und Consulting GmbH
 *
 * based on
 *
 * Rockteck jh057n00900 5.5" MIPI-DSI panel driver
 * Copyright (C) Purism SPC 2019
 */

#include <linux/delay.h>
#include <linux/gpio/consumer.h>
#include <linux/media-bus-format.h>
#include <linux/module.h>
#include <linux/of.h>
#include <linux/regulator/consumer.h>

#include <video/display_timing.h>
#include <video/mipi_display.h>

#include <drm/drm_mipi_dsi.h>
#include <drm/drm_modes.h>
#include <drm/drm_panel.h>

/* Manufacturer specific Commands send via DSI */
#define KD35T133_CMD_INTERFACEMODECTRL          0xb0
#define KD35T133_CMD_FRAMERATECTRL              0xb1
#define KD35T133_CMD_DISPLAYINVERSIONCTRL       0xb4
#define KD35T133_CMD_DISPLAYFUNCTIONCTRL        0xb6
#define KD35T133_CMD_POWERCONTROL1              0xc0
#define KD35T133_CMD_POWERCONTROL2              0xc1
#define KD35T133_CMD_VCOMCONTROL                0xc5
#define KD35T133_CMD_POSITIVEGAMMA              0xe0
#define KD35T133_CMD_NEGATIVEGAMMA              0xe1
#define KD35T133_CMD_SETIMAGEFUNCTION           0xe9
#define KD35T133_CMD_ADJUSTCONTROL3             0xf7

struct kd35t133 {
        struct device *dev;
        struct drm_panel panel;
        struct gpio_desc *reset_gpio;
        struct regulator *vdd;
        struct regulator *iovcc;
        enum drm_panel_orientation orientation;
};

static inline struct kd35t133 *panel_to_kd35t133(struct drm_panel *panel)
{
        return container_of(panel, struct kd35t133, panel);
}

static void kd35t133_init_sequence(struct mipi_dsi_multi_context *dsi_ctx)
{
        /*
         * Init sequence was supplied by the panel vendor with minimal
         * documentation.
         */
        mipi_dsi_dcs_write_seq_multi(dsi_ctx, KD35T133_CMD_POSITIVEGAMMA,
                                     0x00, 0x13, 0x18, 0x04, 0x0f, 0x06, 0x3a, 0x56,
                                     0x4d, 0x03, 0x0a, 0x06, 0x30, 0x3e, 0x0f);
        mipi_dsi_dcs_write_seq_multi(dsi_ctx, KD35T133_CMD_NEGATIVEGAMMA,
                                     0x00, 0x13, 0x18, 0x01, 0x11, 0x06, 0x38, 0x34,
                                     0x4d, 0x06, 0x0d, 0x0b, 0x31, 0x37, 0x0f);
        mipi_dsi_dcs_write_seq_multi(dsi_ctx, KD35T133_CMD_POWERCONTROL1, 0x18, 0x17);
        mipi_dsi_dcs_write_seq_multi(dsi_ctx, KD35T133_CMD_POWERCONTROL2, 0x41);
        mipi_dsi_dcs_write_seq_multi(dsi_ctx, KD35T133_CMD_VCOMCONTROL, 0x00, 0x1a, 0x80);
        mipi_dsi_dcs_write_seq_multi(dsi_ctx, MIPI_DCS_SET_ADDRESS_MODE, 0x48);
        mipi_dsi_dcs_write_seq_multi(dsi_ctx, MIPI_DCS_SET_PIXEL_FORMAT, 0x55);
        mipi_dsi_dcs_write_seq_multi(dsi_ctx, KD35T133_CMD_INTERFACEMODECTRL, 0x00);
        mipi_dsi_dcs_write_seq_multi(dsi_ctx, KD35T133_CMD_FRAMERATECTRL, 0xa0);
        mipi_dsi_dcs_write_seq_multi(dsi_ctx, KD35T133_CMD_DISPLAYINVERSIONCTRL, 0x02);
        mipi_dsi_dcs_write_seq_multi(dsi_ctx, KD35T133_CMD_DISPLAYFUNCTIONCTRL,
                                     0x20, 0x02);
        mipi_dsi_dcs_write_seq_multi(dsi_ctx, KD35T133_CMD_SETIMAGEFUNCTION, 0x00);
        mipi_dsi_dcs_write_seq_multi(dsi_ctx, KD35T133_CMD_ADJUSTCONTROL3,
                                     0xa9, 0x51, 0x2c, 0x82);
        mipi_dsi_dcs_write_seq_multi(dsi_ctx, MIPI_DCS_ENTER_INVERT_MODE);
}

static int kd35t133_unprepare(struct drm_panel *panel)
{
        struct kd35t133 *ctx = panel_to_kd35t133(panel);
        struct mipi_dsi_device *dsi = to_mipi_dsi_device(ctx->dev);
        struct mipi_dsi_multi_context dsi_ctx = { .dsi = dsi };

        mipi_dsi_dcs_set_display_off_multi(&dsi_ctx);
        mipi_dsi_dcs_enter_sleep_mode_multi(&dsi_ctx);
        if (dsi_ctx.accum_err)
                return dsi_ctx.accum_err;

        gpiod_set_value_cansleep(ctx->reset_gpio, 1);

        regulator_disable(ctx->iovcc);
        regulator_disable(ctx->vdd);

        return 0;
}

static int kd35t133_prepare(struct drm_panel *panel)
{
        struct kd35t133 *ctx = panel_to_kd35t133(panel);
        struct mipi_dsi_device *dsi = to_mipi_dsi_device(ctx->dev);
        struct mipi_dsi_multi_context dsi_ctx = { .dsi = dsi };

        dev_dbg(ctx->dev, "Resetting the panel\n");
        dsi_ctx.accum_err = regulator_enable(ctx->vdd);
        if (dsi_ctx.accum_err) {
                dev_err(ctx->dev, "Failed to enable vdd supply: %d\n",
                        dsi_ctx.accum_err);
                return dsi_ctx.accum_err;
        }

        dsi_ctx.accum_err = regulator_enable(ctx->iovcc);
        if (dsi_ctx.accum_err) {
                dev_err(ctx->dev, "Failed to enable iovcc supply: %d\n",
                        dsi_ctx.accum_err);
                goto disable_vdd;
        }

        msleep(20);

        gpiod_set_value_cansleep(ctx->reset_gpio, 1);
        usleep_range(10, 20);
        gpiod_set_value_cansleep(ctx->reset_gpio, 0);

        msleep(20);

        mipi_dsi_dcs_exit_sleep_mode_multi(&dsi_ctx);
        mipi_dsi_msleep(&dsi_ctx, 250);

        kd35t133_init_sequence(&dsi_ctx);
        if (!dsi_ctx.accum_err)
                dev_dbg(ctx->dev, "Panel init sequence done\n");

        mipi_dsi_dcs_set_display_on_multi(&dsi_ctx);
        mipi_dsi_msleep(&dsi_ctx, 50);

        if (dsi_ctx.accum_err)
                goto disable_iovcc;

        return 0;

disable_iovcc:
        regulator_disable(ctx->iovcc);
disable_vdd:
        regulator_disable(ctx->vdd);
        return dsi_ctx.accum_err;
}

static const struct drm_display_mode default_mode = {
        .hdisplay       = 320,
        .hsync_start    = 320 + 130,
        .hsync_end      = 320 + 130 + 4,
        .htotal         = 320 + 130 + 4 + 130,
        .vdisplay       = 480,
        .vsync_start    = 480 + 2,
        .vsync_end      = 480 + 2 + 1,
        .vtotal         = 480 + 2 + 1 + 2,
        .clock          = 17000,
        .width_mm       = 42,
        .height_mm      = 82,
};

static int kd35t133_get_modes(struct drm_panel *panel,
                                struct drm_connector *connector)
{
        struct kd35t133 *ctx = panel_to_kd35t133(panel);
        struct drm_display_mode *mode;

        mode = drm_mode_duplicate(connector->dev, &default_mode);
        if (!mode) {
                dev_err(ctx->dev, "Failed to add mode %ux%u@%u\n",
                        default_mode.hdisplay, default_mode.vdisplay,
                        drm_mode_vrefresh(&default_mode));
                return -ENOMEM;
        }

        drm_mode_set_name(mode);

        mode->type = DRM_MODE_TYPE_DRIVER | DRM_MODE_TYPE_PREFERRED;
        connector->display_info.width_mm = mode->width_mm;
        connector->display_info.height_mm = mode->height_mm;
        drm_mode_probed_add(connector, mode);

        return 1;
}

static enum drm_panel_orientation kd35t133_get_orientation(struct drm_panel *panel)
{
        struct kd35t133 *ctx = panel_to_kd35t133(panel);

        return ctx->orientation;
}

static const struct drm_panel_funcs kd35t133_funcs = {
        .unprepare      = kd35t133_unprepare,
        .prepare        = kd35t133_prepare,
        .get_modes      = kd35t133_get_modes,
        .get_orientation = kd35t133_get_orientation,
};

static int kd35t133_probe(struct mipi_dsi_device *dsi)
{
        struct device *dev = &dsi->dev;
        struct kd35t133 *ctx;
        int ret;

        ctx = devm_drm_panel_alloc(dev, struct kd35t133, panel,
                                   &kd35t133_funcs, DRM_MODE_CONNECTOR_DSI);
        if (IS_ERR(ctx))
                return PTR_ERR(ctx);

        ctx->reset_gpio = devm_gpiod_get_optional(dev, "reset", GPIOD_OUT_LOW);
        if (IS_ERR(ctx->reset_gpio)) {
                dev_err(dev, "cannot get reset gpio\n");
                return PTR_ERR(ctx->reset_gpio);
        }

        ctx->vdd = devm_regulator_get(dev, "vdd");
        if (IS_ERR(ctx->vdd)) {
                ret = PTR_ERR(ctx->vdd);
                if (ret != -EPROBE_DEFER)
                        dev_err(dev, "Failed to request vdd regulator: %d\n", ret);
                return ret;
        }

        ctx->iovcc = devm_regulator_get(dev, "iovcc");
        if (IS_ERR(ctx->iovcc)) {
                ret = PTR_ERR(ctx->iovcc);
                if (ret != -EPROBE_DEFER)
                        dev_err(dev, "Failed to request iovcc regulator: %d\n", ret);
                return ret;
        }

        ret = of_drm_get_panel_orientation(dev->of_node, &ctx->orientation);
        if (ret < 0) {
                dev_err(dev, "%pOF: failed to get orientation %d\n", dev->of_node, ret);
                return ret;
        }

        mipi_dsi_set_drvdata(dsi, ctx);

        ctx->dev = dev;

        dsi->lanes = 1;
        dsi->format = MIPI_DSI_FMT_RGB888;
        dsi->mode_flags = MIPI_DSI_MODE_VIDEO | MIPI_DSI_MODE_VIDEO_BURST |
                          MIPI_DSI_MODE_LPM | MIPI_DSI_MODE_NO_EOT_PACKET |
                          MIPI_DSI_CLOCK_NON_CONTINUOUS;

        ret = drm_panel_of_backlight(&ctx->panel);
        if (ret)
                return ret;

        drm_panel_add(&ctx->panel);

        ret = mipi_dsi_attach(dsi);
        if (ret < 0) {
                dev_err(dev, "mipi_dsi_attach failed: %d\n", ret);
                drm_panel_remove(&ctx->panel);
                return ret;
        }

        return 0;
}

static void kd35t133_remove(struct mipi_dsi_device *dsi)
{
        struct kd35t133 *ctx = mipi_dsi_get_drvdata(dsi);
        int ret;

        ret = mipi_dsi_detach(dsi);
        if (ret < 0)
                dev_err(&dsi->dev, "Failed to detach from DSI host: %d\n", ret);

        drm_panel_remove(&ctx->panel);
}

static const struct of_device_id kd35t133_of_match[] = {
        { .compatible = "elida,kd35t133" },
        { /* sentinel */ }
};
MODULE_DEVICE_TABLE(of, kd35t133_of_match);

static struct mipi_dsi_driver kd35t133_driver = {
        .driver = {
                .name = "panel-elida-kd35t133",
                .of_match_table = kd35t133_of_match,
        },
        .probe  = kd35t133_probe,
        .remove = kd35t133_remove,
};
module_mipi_dsi_driver(kd35t133_driver);

MODULE_AUTHOR("Heiko Stuebner <heiko.stuebner@theobroma-systems.com>");
MODULE_DESCRIPTION("DRM driver for Elida kd35t133 MIPI DSI panel");
MODULE_LICENSE("GPL v2");