// SPDX-License-Identifier: GPL-2.0
/*
 * Sharp LS037V7DW01 LCD Panel Driver
 *
 * Copyright (C) 2019 Texas Instruments Incorporated
 *
 * Based on the omapdrm-specific panel-sharp-ls037v7dw01 driver
 *
 * Copyright (C) 2013 Texas Instruments Incorporated
 * Author: Tomi Valkeinen <tomi.valkeinen@ti.com>
 */

#include <linux/delay.h>
#include <linux/gpio/consumer.h>
#include <linux/module.h>
#include <linux/of.h>
#include <linux/platform_device.h>
#include <linux/regulator/consumer.h>

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

struct ls037v7dw01_panel {
        struct drm_panel panel;
        struct platform_device *pdev;

        struct regulator *vdd;
        struct gpio_desc *resb_gpio;    /* low = reset active min 20 us */
        struct gpio_desc *ini_gpio;     /* high = power on */
        struct gpio_desc *mo_gpio;      /* low = 480x640, high = 240x320 */
        struct gpio_desc *lr_gpio;      /* high = conventional horizontal scanning */
        struct gpio_desc *ud_gpio;      /* high = conventional vertical scanning */
};

#define to_ls037v7dw01_device(p) \
        container_of(p, struct ls037v7dw01_panel, panel)

static int ls037v7dw01_disable(struct drm_panel *panel)
{
        struct ls037v7dw01_panel *lcd = to_ls037v7dw01_device(panel);

        gpiod_set_value_cansleep(lcd->ini_gpio, 0);
        gpiod_set_value_cansleep(lcd->resb_gpio, 0);

        /* Wait at least 5 vsyncs after disabling the LCD. */
        msleep(100);

        return 0;
}

static int ls037v7dw01_unprepare(struct drm_panel *panel)
{
        struct ls037v7dw01_panel *lcd = to_ls037v7dw01_device(panel);

        regulator_disable(lcd->vdd);
        return 0;
}

static int ls037v7dw01_prepare(struct drm_panel *panel)
{
        struct ls037v7dw01_panel *lcd = to_ls037v7dw01_device(panel);
        int ret;

        ret = regulator_enable(lcd->vdd);
        if (ret < 0)
                dev_err(&lcd->pdev->dev, "%s: failed to enable regulator\n",
                        __func__);

        return ret;
}

static int ls037v7dw01_enable(struct drm_panel *panel)
{
        struct ls037v7dw01_panel *lcd = to_ls037v7dw01_device(panel);

        /* Wait couple of vsyncs before enabling the LCD. */
        msleep(50);

        gpiod_set_value_cansleep(lcd->resb_gpio, 1);
        gpiod_set_value_cansleep(lcd->ini_gpio, 1);

        return 0;
}

static const struct drm_display_mode ls037v7dw01_mode = {
        .clock = 19200,
        .hdisplay = 480,
        .hsync_start = 480 + 1,
        .hsync_end = 480 + 1 + 2,
        .htotal = 480 + 1 + 2 + 28,
        .vdisplay = 640,
        .vsync_start = 640 + 1,
        .vsync_end = 640 + 1 + 1,
        .vtotal = 640 + 1 + 1 + 1,
        .type = DRM_MODE_TYPE_DRIVER | DRM_MODE_TYPE_PREFERRED,
        .flags = DRM_MODE_FLAG_NHSYNC | DRM_MODE_FLAG_NVSYNC,
        .width_mm = 56,
        .height_mm = 75,
};

static int ls037v7dw01_get_modes(struct drm_panel *panel,
                                 struct drm_connector *connector)
{
        struct drm_display_mode *mode;

        mode = drm_mode_duplicate(connector->dev, &ls037v7dw01_mode);
        if (!mode)
                return -ENOMEM;

        drm_mode_set_name(mode);
        drm_mode_probed_add(connector, mode);

        connector->display_info.width_mm = ls037v7dw01_mode.width_mm;
        connector->display_info.height_mm = ls037v7dw01_mode.height_mm;
        /*
         * FIXME: According to the datasheet pixel data is sampled on the
         * rising edge of the clock, but the code running on the SDP3430
         * indicates sampling on the negative edge. This should be tested on a
         * real device.
         */
        connector->display_info.bus_flags = DRM_BUS_FLAG_DE_HIGH
                                          | DRM_BUS_FLAG_SYNC_SAMPLE_POSEDGE
                                          | DRM_BUS_FLAG_PIXDATA_SAMPLE_NEGEDGE;

        return 1;
}

static const struct drm_panel_funcs ls037v7dw01_funcs = {
        .disable = ls037v7dw01_disable,
        .unprepare = ls037v7dw01_unprepare,
        .prepare = ls037v7dw01_prepare,
        .enable = ls037v7dw01_enable,
        .get_modes = ls037v7dw01_get_modes,
};

static int ls037v7dw01_probe(struct platform_device *pdev)
{
        struct ls037v7dw01_panel *lcd;

        lcd = devm_drm_panel_alloc(&pdev->dev, struct ls037v7dw01_panel, panel,
                                   &ls037v7dw01_funcs, DRM_MODE_CONNECTOR_DPI);
        if (IS_ERR(lcd))
                return PTR_ERR(lcd);

        platform_set_drvdata(pdev, lcd);
        lcd->pdev = pdev;

        lcd->vdd = devm_regulator_get(&pdev->dev, "envdd");
        if (IS_ERR(lcd->vdd))
                return dev_err_probe(&pdev->dev, PTR_ERR(lcd->vdd),
                                     "failed to get regulator\n");

        lcd->ini_gpio = devm_gpiod_get(&pdev->dev, "enable", GPIOD_OUT_LOW);
        if (IS_ERR(lcd->ini_gpio))
                return dev_err_probe(&pdev->dev, PTR_ERR(lcd->ini_gpio),
                                     "failed to get enable gpio\n");

        lcd->resb_gpio = devm_gpiod_get(&pdev->dev, "reset", GPIOD_OUT_LOW);
        if (IS_ERR(lcd->resb_gpio))
                return dev_err_probe(&pdev->dev, PTR_ERR(lcd->resb_gpio),
                                     "failed to get reset gpio\n");

        lcd->mo_gpio = devm_gpiod_get_index(&pdev->dev, "mode", 0,
                                            GPIOD_OUT_LOW);
        if (IS_ERR(lcd->mo_gpio)) {
                dev_err(&pdev->dev, "failed to get mode[0] gpio\n");
                return PTR_ERR(lcd->mo_gpio);
        }

        lcd->lr_gpio = devm_gpiod_get_index(&pdev->dev, "mode", 1,
                                            GPIOD_OUT_LOW);
        if (IS_ERR(lcd->lr_gpio)) {
                dev_err(&pdev->dev, "failed to get mode[1] gpio\n");
                return PTR_ERR(lcd->lr_gpio);
        }

        lcd->ud_gpio = devm_gpiod_get_index(&pdev->dev, "mode", 2,
                                            GPIOD_OUT_LOW);
        if (IS_ERR(lcd->ud_gpio)) {
                dev_err(&pdev->dev, "failed to get mode[2] gpio\n");
                return PTR_ERR(lcd->ud_gpio);
        }

        drm_panel_add(&lcd->panel);

        return 0;
}

static void ls037v7dw01_remove(struct platform_device *pdev)
{
        struct ls037v7dw01_panel *lcd = platform_get_drvdata(pdev);

        drm_panel_remove(&lcd->panel);
        drm_panel_disable(&lcd->panel);
        drm_panel_unprepare(&lcd->panel);
}

static const struct of_device_id ls037v7dw01_of_match[] = {
        { .compatible = "sharp,ls037v7dw01", },
        { /* sentinel */ },
};

MODULE_DEVICE_TABLE(of, ls037v7dw01_of_match);

static struct platform_driver ls037v7dw01_driver = {
        .probe          = ls037v7dw01_probe,
        .remove         = ls037v7dw01_remove,
        .driver         = {
                .name = "panel-sharp-ls037v7dw01",
                .of_match_table = ls037v7dw01_of_match,
        },
};

module_platform_driver(ls037v7dw01_driver);

MODULE_AUTHOR("Tomi Valkeinen <tomi.valkeinen@ti.com>");
MODULE_DESCRIPTION("Sharp LS037V7DW01 Panel Driver");
MODULE_LICENSE("GPL");