// SPDX-License-Identifier: GPL-2.0-only
// Copyright (c) 2024 Linaro Limited

#include <linux/backlight.h>
#include <linux/delay.h>
#include <linux/gpio/consumer.h>
#include <linux/regulator/consumer.h>
#include <linux/mod_devicetable.h>
#include <linux/module.h>

#include <drm/display/drm_dsc.h>
#include <drm/display/drm_dsc_helper.h>
#include <drm/drm_mipi_dsi.h>
#include <drm/drm_modes.h>
#include <drm/drm_panel.h>
#include <drm/drm_probe_helper.h>

#include <video/mipi_display.h>

struct novatek_nt37801 {
        struct drm_panel panel;
        struct mipi_dsi_device *dsi;
        struct drm_dsc_config dsc;
        struct gpio_desc *reset_gpio;
        struct regulator_bulk_data *supplies;
};

static const struct regulator_bulk_data novatek_nt37801_supplies[] = {
        { .supply = "vddio" },
        { .supply = "vci" },
        { .supply = "vdd" },
};

static inline struct novatek_nt37801 *to_novatek_nt37801(struct drm_panel *panel)
{
        return container_of(panel, struct novatek_nt37801, panel);
}

static void novatek_nt37801_reset(struct novatek_nt37801 *ctx)
{
        gpiod_set_value_cansleep(ctx->reset_gpio, 0);
        usleep_range(10000, 21000);
        gpiod_set_value_cansleep(ctx->reset_gpio, 1);
        usleep_range(10000, 21000);
        gpiod_set_value_cansleep(ctx->reset_gpio, 0);
        usleep_range(10000, 21000);
}

#define NT37801_DCS_SWITCH_PAGE                 0xf0

#define novatek_nt37801_switch_page(dsi_ctx, page) \
        mipi_dsi_dcs_write_seq_multi((dsi_ctx), NT37801_DCS_SWITCH_PAGE, \
                                     0x55, 0xaa, 0x52, 0x08, (page))

static int novatek_nt37801_on(struct novatek_nt37801 *ctx)
{
        struct mipi_dsi_device *dsi = ctx->dsi;
        struct mipi_dsi_multi_context dsi_ctx = { .dsi = dsi };

        dsi->mode_flags |= MIPI_DSI_MODE_LPM;

        novatek_nt37801_switch_page(&dsi_ctx, 0x01);
        mipi_dsi_dcs_write_seq_multi(&dsi_ctx, 0x6f, 0x01);
        mipi_dsi_dcs_write_seq_multi(&dsi_ctx, 0xc5, 0x0b, 0x0b, 0x0b);
        mipi_dsi_dcs_write_seq_multi(&dsi_ctx, 0xff, 0xaa, 0x55, 0xa5, 0x80);
        mipi_dsi_dcs_write_seq_multi(&dsi_ctx, 0x6f, 0x02);
        mipi_dsi_dcs_write_seq_multi(&dsi_ctx, 0xf5, 0x10);
        mipi_dsi_dcs_write_seq_multi(&dsi_ctx, 0x6f, 0x1b);
        mipi_dsi_dcs_write_seq_multi(&dsi_ctx, 0xf4, 0x55);
        mipi_dsi_dcs_write_seq_multi(&dsi_ctx, 0x6f, 0x18);
        mipi_dsi_dcs_write_seq_multi(&dsi_ctx, 0xf8, 0x19);
        mipi_dsi_dcs_write_seq_multi(&dsi_ctx, 0x6f, 0x0f);
        mipi_dsi_dcs_write_seq_multi(&dsi_ctx, 0xfc, 0x00);
        mipi_dsi_dcs_set_column_address_multi(&dsi_ctx, 0x0000, 0x059f);
        mipi_dsi_dcs_set_page_address_multi(&dsi_ctx, 0x0000, 0x0c7f);
        mipi_dsi_dcs_write_seq_multi(&dsi_ctx, 0x90, 0x03, 0x03);
        mipi_dsi_dcs_write_seq_multi(&dsi_ctx, 0x91,
                                     0x89, 0x28, 0x00, 0x28, 0xc2, 0x00, 0x02,
                                     0x68, 0x04, 0x6c, 0x00, 0x0a, 0x02, 0x77,
                                     0x01, 0xe9, 0x10, 0xf0);
        mipi_dsi_dcs_write_seq_multi(&dsi_ctx, 0xff, 0xaa, 0x55, 0xa5, 0x81);
        mipi_dsi_dcs_write_seq_multi(&dsi_ctx, 0x6f, 0x23);
        mipi_dsi_dcs_write_seq_multi(&dsi_ctx, 0xfb,
                                     0x00, 0x01, 0x00, 0x11, 0x33, 0x33, 0x33,
                                     0x55, 0x57, 0xd0, 0x00, 0x00, 0x44, 0x56,
                                     0x77, 0x78, 0x9a, 0xbc, 0xdd, 0xf0);
        mipi_dsi_dcs_write_seq_multi(&dsi_ctx, 0x6f, 0x06);
        mipi_dsi_dcs_write_seq_multi(&dsi_ctx, 0xf3, 0xdc);
        mipi_dsi_dcs_write_seq_multi(&dsi_ctx, MIPI_DCS_SET_GAMMA_CURVE, 0x00);
        mipi_dsi_dcs_set_tear_on_multi(&dsi_ctx, MIPI_DSI_DCS_TEAR_MODE_VBLANK);
        mipi_dsi_dcs_write_seq_multi(&dsi_ctx, 0x3b, 0x00, 0x18, 0x00, 0x10);
        mipi_dsi_dcs_write_seq_multi(&dsi_ctx, MIPI_DCS_WRITE_CONTROL_DISPLAY,
                                     0x20);
        mipi_dsi_dcs_write_seq_multi(&dsi_ctx, 0x51,
                                     0x07, 0xff, 0x07, 0xff, 0x0f, 0xff);
        mipi_dsi_dcs_write_seq_multi(&dsi_ctx, 0x5a, 0x01);
        mipi_dsi_dcs_write_seq_multi(&dsi_ctx, 0x5f, 0x00);
        mipi_dsi_dcs_write_seq_multi(&dsi_ctx, 0x9c, 0x01);
        mipi_dsi_dcs_write_seq_multi(&dsi_ctx, MIPI_DCS_WRITE_MEMORY_START);
        mipi_dsi_dcs_write_seq_multi(&dsi_ctx, 0x2f, 0x00);

        novatek_nt37801_switch_page(&dsi_ctx, 0x01);
        mipi_dsi_dcs_write_seq_multi(&dsi_ctx, 0xb2, 0x55, 0x01, 0xff, 0x03);
        mipi_dsi_dcs_exit_sleep_mode_multi(&dsi_ctx);
        mipi_dsi_msleep(&dsi_ctx, 120);
        mipi_dsi_dcs_set_display_on_multi(&dsi_ctx);
        mipi_dsi_msleep(&dsi_ctx, 20);

        return dsi_ctx.accum_err;
}

static int novatek_nt37801_off(struct novatek_nt37801 *ctx)
{
        struct mipi_dsi_device *dsi = ctx->dsi;
        struct mipi_dsi_multi_context dsi_ctx = { .dsi = dsi };

        dsi->mode_flags &= ~MIPI_DSI_MODE_LPM;

        mipi_dsi_dcs_set_display_off_multi(&dsi_ctx);
        mipi_dsi_msleep(&dsi_ctx, 20);

        mipi_dsi_dcs_enter_sleep_mode_multi(&dsi_ctx);
        mipi_dsi_msleep(&dsi_ctx, 120);

        return dsi_ctx.accum_err;
}

static int novatek_nt37801_prepare(struct drm_panel *panel)
{
        struct novatek_nt37801 *ctx = to_novatek_nt37801(panel);
        struct device *dev = &ctx->dsi->dev;
        struct drm_dsc_picture_parameter_set pps;
        int ret;

        ret = regulator_bulk_enable(ARRAY_SIZE(novatek_nt37801_supplies),
                                    ctx->supplies);
        if (ret < 0)
                return ret;

        novatek_nt37801_reset(ctx);

        ret = novatek_nt37801_on(ctx);
        if (ret < 0)
                goto err;

        drm_dsc_pps_payload_pack(&pps, &ctx->dsc);

        ret = mipi_dsi_picture_parameter_set(ctx->dsi, &pps);
        if (ret < 0) {
                dev_err(panel->dev, "failed to transmit PPS: %d\n", ret);
                goto err;
        }

        ret = mipi_dsi_compression_mode(ctx->dsi, true);
        if (ret < 0) {
                dev_err(dev, "failed to enable compression mode: %d\n", ret);
                goto err;
        }

        msleep(28);

        return 0;

err:
        gpiod_set_value_cansleep(ctx->reset_gpio, 1);
        regulator_bulk_disable(ARRAY_SIZE(novatek_nt37801_supplies),
                               ctx->supplies);

        return ret;
}

static int novatek_nt37801_unprepare(struct drm_panel *panel)
{
        struct novatek_nt37801 *ctx = to_novatek_nt37801(panel);
        struct device *dev = &ctx->dsi->dev;
        int ret;

        ret = novatek_nt37801_off(ctx);
        if (ret < 0)
                dev_err(dev, "Failed to un-initialize panel: %d\n", ret);

        gpiod_set_value_cansleep(ctx->reset_gpio, 1);

        regulator_bulk_disable(ARRAY_SIZE(novatek_nt37801_supplies),
                               ctx->supplies);

        return 0;
}

static const struct drm_display_mode novatek_nt37801_mode = {
        .clock = (1440 + 20 + 4 + 20) * (3200 + 20 + 2 + 18) * 120 / 1000,
        .hdisplay = 1440,
        .hsync_start = 1440 + 20,
        .hsync_end = 1440 + 20 + 4,
        .htotal = 1440 + 20 + 4 + 20,
        .vdisplay = 3200,
        .vsync_start = 3200 + 20,
        .vsync_end = 3200 + 20 + 2,
        .vtotal = 3200 + 20 + 2 + 18,
        .type = DRM_MODE_TYPE_DRIVER,
};

static int novatek_nt37801_get_modes(struct drm_panel *panel,
                                     struct drm_connector *connector)
{
        return drm_connector_helper_get_modes_fixed(connector,
                                                    &novatek_nt37801_mode);
}

static const struct drm_panel_funcs novatek_nt37801_panel_funcs = {
        .prepare = novatek_nt37801_prepare,
        .unprepare = novatek_nt37801_unprepare,
        .get_modes = novatek_nt37801_get_modes,
};

static int novatek_nt37801_bl_update_status(struct backlight_device *bl)
{
        struct mipi_dsi_device *dsi = bl_get_data(bl);
        u16 brightness = backlight_get_brightness(bl);
        int ret;

        dsi->mode_flags &= ~MIPI_DSI_MODE_LPM;

        ret = mipi_dsi_dcs_set_display_brightness_large(dsi, brightness);
        if (ret < 0)
                return ret;

        dsi->mode_flags |= MIPI_DSI_MODE_LPM;

        return 0;
}

static const struct backlight_ops novatek_nt37801_bl_ops = {
        .update_status = novatek_nt37801_bl_update_status,
};

static struct backlight_device *
novatek_nt37801_create_backlight(struct mipi_dsi_device *dsi)
{
        struct device *dev = &dsi->dev;
        const struct backlight_properties props = {
                .type = BACKLIGHT_RAW,
                .brightness = 4095,
                .max_brightness = 4095,
        };

        return devm_backlight_device_register(dev, dev_name(dev), dev, dsi,
                                              &novatek_nt37801_bl_ops, &props);
}

static int novatek_nt37801_probe(struct mipi_dsi_device *dsi)
{
        struct device *dev = &dsi->dev;
        struct novatek_nt37801 *ctx;
        int ret;

        ctx = devm_drm_panel_alloc(dev, struct novatek_nt37801, panel,
                                   &novatek_nt37801_panel_funcs,
                                   DRM_MODE_CONNECTOR_DSI);
        if (IS_ERR(ctx))
                return PTR_ERR(ctx);

        ret = devm_regulator_bulk_get_const(dev,
                                            ARRAY_SIZE(novatek_nt37801_supplies),
                                            novatek_nt37801_supplies,
                                            &ctx->supplies);
        if (ret < 0)
                return ret;

        ctx->reset_gpio = devm_gpiod_get(dev, "reset", GPIOD_OUT_LOW);
        if (IS_ERR(ctx->reset_gpio))
                return dev_err_probe(dev, PTR_ERR(ctx->reset_gpio),
                                     "Failed to get reset-gpios\n");

        ctx->dsi = dsi;
        mipi_dsi_set_drvdata(dsi, ctx);

        dsi->lanes = 4;
        dsi->format = MIPI_DSI_FMT_RGB888;
        dsi->mode_flags = MIPI_DSI_MODE_NO_EOT_PACKET | MIPI_DSI_CLOCK_NON_CONTINUOUS;

        ctx->panel.prepare_prev_first = true;
        ctx->panel.backlight = novatek_nt37801_create_backlight(dsi);
        if (IS_ERR(ctx->panel.backlight))
                return dev_err_probe(dev, PTR_ERR(ctx->panel.backlight),
                                     "Failed to create backlight\n");

        drm_panel_add(&ctx->panel);

        /* This panel only supports DSC; unconditionally enable it */
        dsi->dsc = &ctx->dsc;
        ctx->dsc.dsc_version_major = 1;
        ctx->dsc.dsc_version_minor = 1;
        ctx->dsc.slice_height = 40;
        ctx->dsc.slice_width = 720;
        ctx->dsc.slice_count = 1440 / ctx->dsc.slice_width;
        ctx->dsc.bits_per_component = 8;
        ctx->dsc.bits_per_pixel = 8 << 4; /* 4 fractional bits */
        ctx->dsc.block_pred_enable = true;

        ret = mipi_dsi_attach(dsi);
        if (ret < 0) {
                drm_panel_remove(&ctx->panel);
                return dev_err_probe(dev, ret, "Failed to attach to DSI host\n");
        }

        return 0;
}

static void novatek_nt37801_remove(struct mipi_dsi_device *dsi)
{
        struct novatek_nt37801 *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 novatek_nt37801_of_match[] = {
        { .compatible = "novatek,nt37801" },
        {}
};
MODULE_DEVICE_TABLE(of, novatek_nt37801_of_match);

static struct mipi_dsi_driver novatek_nt37801_driver = {
        .probe = novatek_nt37801_probe,
        .remove = novatek_nt37801_remove,
        .driver = {
                .name = "panel-novatek-nt37801",
                .of_match_table = novatek_nt37801_of_match,
        },
};
module_mipi_dsi_driver(novatek_nt37801_driver);

MODULE_AUTHOR("Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>");
MODULE_DESCRIPTION("Panel driver for the Novatek NT37801/NT37810 AMOLED DSI panel");
MODULE_LICENSE("GPL");