// SPDX-License-Identifier: GPL-2.0-only
/*
 * JDI LPM062M326A 720x1280 MIPI-DSI panel, as used on the Nintendo Switch.
 *
 * Ported from switchroot's mainline patch 0010:
 *   reference/switchroot-mainline/0010-v0-drm-panel-add-driver-for-jdi-lpm062m326a.patch
 * The display timings, the panel-ID check and the init sequence are theirs.
 * Original author: SwtcR <swtcr0@gmail.com>.
 *
 * Changes for the current DRM panel API: devm_drm_panel_alloc() replaces the
 * manual drm_panel_init()/funcs/dev assignment, get_modes() takes the connector
 * as an argument, drm_panel_attach/detach are gone, and devm_of_find_backlight()
 * replaces of_find_backlight_by_node(). drmP.h no longer exists.
 */

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

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

#include <video/mipi_display.h>

struct jdi_panel {
	struct drm_panel base;
	struct mipi_dsi_device *dsi;

	struct backlight_device *backlight;
	struct regulator *supply1;
	struct regulator *supply2;
	struct gpio_desc *reset_gpio;

	bool prepared;
	bool enabled;

	const struct drm_display_mode *mode;
};

struct init_cmd {
	u8 cmd;
	int length;
	u8 data[0x40];
};

/*
 * The panel reports its ID via MIPI_DCS_GET_DISPLAY_ID and the Switch shipped
 * more than one LCD; this is the sequence for the 0x10 variant. Unknown IDs get
 * no extra init, which is what the original driver does too.
 */
static const struct init_cmd init_cmds_0x10[] = {
	{ 0xb9, 3,    { 0xff, 0x83, 0x94 }},
	{ 0xbd, 1,    { 0x00 }},
	{ 0xd8, 0x18, { 0xaa, 0xaa, 0xaa, 0xeb, 0xaa, 0xaa,
			0xaa, 0xaa, 0xaa, 0xeb, 0xaa, 0xaa,
			0xaa, 0xaa, 0xaa, 0xeb, 0xaa, 0xaa,
			0xaa, 0xaa, 0xaa, 0xeb, 0xaa, 0xaa }},
	{ 0xbd, 1,    { 0x01 }},
	{ 0xd8, 0x26, { 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff,
			0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff,
			0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff,
			0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff,
			0xff, 0xff, 0xff, 0xff, 0xff, 0xff }},
	{ 0xbd, 1,    { 0x02 }},
	{ 0xd8, 0x0e, { 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff,
			0xff, 0xff, 0xff, 0xff, 0xff, 0xff }},
	{ 0xbd, 1,    { 0x00 }},
	{ 0xd9, 1,    { 0x06 }},
	{ 0xb9, 3,    { 0x00, 0x00, 0x00 }},
	{ 0x00, -1,   { 0x00 }},	/* terminator */
};

static inline struct jdi_panel *to_jdi_panel(struct drm_panel *panel)
{
	return container_of(panel, struct jdi_panel, base);
}

static int jdi_panel_init(struct jdi_panel *jdi)
{
	struct mipi_dsi_device *dsi = jdi->dsi;
	const struct init_cmd *init_cmds = NULL;
	u8 display_id[3] = { 0 };
	int ret;

	dsi->mode_flags |= MIPI_DSI_MODE_LPM;

	ret = mipi_dsi_set_maximum_return_packet_size(dsi, 3);
	if (ret < 0)
		return ret;

	ret = mipi_dsi_dcs_read(dsi, MIPI_DCS_GET_DISPLAY_ID, display_id,
				sizeof(display_id));
	if (ret < 0)
		dev_err(&dsi->dev, "failed to read panel ID: %d\n", ret);
	else
		dev_info(&dsi->dev, "display ID[%d]: %02x %02x %02x\n",
			 ret, display_id[0], display_id[1], display_id[2]);

	switch (display_id[0]) {
	case 0x10:
		dev_info(&dsi->dev, "using init sequence for ID 0x10\n");
		init_cmds = init_cmds_0x10;
		break;
	default:
		dev_info(&dsi->dev, "unknown display, no extra init\n");
		break;
	}

	msleep(10);

	ret = mipi_dsi_dcs_exit_sleep_mode(dsi);
	if (ret < 0)
		return ret;

	for (; init_cmds && init_cmds->length != -1; init_cmds++) {
		ret = mipi_dsi_dcs_write(dsi, init_cmds->cmd, init_cmds->data,
					 init_cmds->length);
		if (ret < 0)
			return ret;
	}

	msleep(180);

	ret = mipi_dsi_dcs_set_column_address(dsi, 0, jdi->mode->hdisplay - 1);
	if (ret < 0)
		return ret;

	ret = mipi_dsi_dcs_set_page_address(dsi, 0, jdi->mode->vdisplay - 1);
	if (ret < 0)
		return ret;

	ret = mipi_dsi_dcs_set_tear_on(dsi, MIPI_DSI_DCS_TEAR_MODE_VBLANK);
	if (ret < 0)
		return ret;

	ret = mipi_dsi_dcs_set_pixel_format(dsi, MIPI_DCS_PIXEL_FMT_24BIT);
	if (ret < 0)
		return ret;

	return 0;
}

static int jdi_panel_on(struct jdi_panel *jdi)
{
	struct mipi_dsi_device *dsi = jdi->dsi;
	int ret;

	dsi->mode_flags |= MIPI_DSI_MODE_LPM;

	ret = mipi_dsi_dcs_set_display_on(dsi);
	if (ret < 0)
		return ret;

	msleep(20);

	return 0;
}

static int jdi_panel_off(struct jdi_panel *jdi)
{
	struct mipi_dsi_device *dsi = jdi->dsi;
	int ret;

	dsi->mode_flags &= ~MIPI_DSI_MODE_LPM;

	ret = mipi_dsi_dcs_set_display_off(dsi);
	if (ret < 0)
		return ret;

	ret = mipi_dsi_dcs_enter_sleep_mode(dsi);
	if (ret < 0)
		return ret;

	return 0;
}

static int jdi_panel_disable(struct drm_panel *panel)
{
	struct jdi_panel *jdi = to_jdi_panel(panel);

	if (!jdi->enabled)
		return 0;

	if (jdi->backlight) {
		jdi->backlight->props.power = BACKLIGHT_POWER_OFF;
		backlight_update_status(jdi->backlight);
	}

	jdi->enabled = false;

	return 0;
}

static int jdi_panel_unprepare(struct drm_panel *panel)
{
	struct jdi_panel *jdi = to_jdi_panel(panel);
	int ret;

	if (!jdi->prepared)
		return 0;

	ret = jdi_panel_off(jdi);
	if (ret < 0) {
		dev_err(panel->dev, "failed to set panel off: %d\n", ret);
		return ret;
	}

	if (jdi->reset_gpio)
		gpiod_set_value(jdi->reset_gpio, 0);

	msleep(10);
	regulator_disable(jdi->supply2);
	msleep(10);
	regulator_disable(jdi->supply1);

	jdi->prepared = false;

	return 0;
}

static int jdi_panel_prepare(struct drm_panel *panel)
{
	struct jdi_panel *jdi = to_jdi_panel(panel);
	int ret;

	if (jdi->prepared)
		return 0;

	ret = regulator_enable(jdi->supply1);
	if (ret < 0)
		return ret;
	msleep(10);

	ret = regulator_enable(jdi->supply2);
	if (ret < 0)
		goto poweroff1;
	msleep(10);

	if (jdi->reset_gpio) {
		gpiod_set_value(jdi->reset_gpio, 0);
		msleep(10);
		gpiod_set_value(jdi->reset_gpio, 1);
		msleep(60);
	}

	ret = jdi_panel_init(jdi);
	if (ret < 0) {
		dev_err(panel->dev, "failed to init panel: %d\n", ret);
		goto reset;
	}

	ret = jdi_panel_on(jdi);
	if (ret < 0) {
		dev_err(panel->dev, "failed to set panel on: %d\n", ret);
		goto reset;
	}

	jdi->prepared = true;

	return 0;

reset:
	if (jdi->reset_gpio)
		gpiod_set_value(jdi->reset_gpio, 0);
	regulator_disable(jdi->supply2);
poweroff1:
	regulator_disable(jdi->supply1);
	return ret;
}

static int jdi_panel_enable(struct drm_panel *panel)
{
	struct jdi_panel *jdi = to_jdi_panel(panel);

	if (jdi->enabled)
		return 0;

	if (jdi->backlight) {
		jdi->backlight->props.power = BACKLIGHT_POWER_ON;
		backlight_update_status(jdi->backlight);
	}

	jdi->enabled = true;

	return 0;
}

/* 720x1280 @ 60Hz, from switchroot's driver. Modern kernels compute vrefresh
 * from the timings, so it is not set here. */
static const struct drm_display_mode default_mode = {
	.clock = 78000,
	.hdisplay = 720,
	.hsync_start = 720 + 136,
	.hsync_end = 720 + 136 + 72,
	.htotal = 720 + 136 + 72 + 72,
	.vdisplay = 1280,
	.vsync_start = 1280 + 10,
	.vsync_end = 1280 + 10 + 2,
	.vtotal = 1280 + 10 + 1 + 9,
	.type = DRM_MODE_TYPE_DRIVER | DRM_MODE_TYPE_PREFERRED,
};

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

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

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

	connector->display_info.width_mm = 77;
	connector->display_info.height_mm = 137;

	return 1;
}

static const struct drm_panel_funcs jdi_panel_funcs = {
	.disable = jdi_panel_disable,
	.unprepare = jdi_panel_unprepare,
	.prepare = jdi_panel_prepare,
	.enable = jdi_panel_enable,
	.get_modes = jdi_panel_get_modes,
};

static int jdi_panel_add(struct jdi_panel *jdi)
{
	struct device *dev = &jdi->dsi->dev;

	jdi->mode = &default_mode;

	jdi->supply1 = devm_regulator_get(dev, "vdd1");
	if (IS_ERR(jdi->supply1))
		return dev_err_probe(dev, PTR_ERR(jdi->supply1), "vdd1\n");

	jdi->supply2 = devm_regulator_get(dev, "vdd2");
	if (IS_ERR(jdi->supply2))
		return dev_err_probe(dev, PTR_ERR(jdi->supply2), "vdd2\n");

	jdi->reset_gpio = devm_gpiod_get(dev, "reset", GPIOD_OUT_LOW);
	if (IS_ERR(jdi->reset_gpio)) {
		dev_err(dev, "cannot get reset-gpios: %ld\n",
			PTR_ERR(jdi->reset_gpio));
		jdi->reset_gpio = NULL;
	} else {
		gpiod_set_value(jdi->reset_gpio, 0);
	}

	jdi->backlight = devm_of_find_backlight(dev);
	if (IS_ERR(jdi->backlight))
		return PTR_ERR(jdi->backlight);

	drm_panel_add(&jdi->base);

	return 0;
}

static void jdi_panel_del(struct jdi_panel *jdi)
{
	drm_panel_remove(&jdi->base);
}

static int jdi_panel_probe(struct mipi_dsi_device *dsi)
{
	struct jdi_panel *jdi;
	int ret;

	dsi->lanes = 4;
	dsi->format = MIPI_DSI_FMT_RGB888;
	/*
	 * The original set MIPI_DSI_MODE_EOT_PACKET. That flag is gone: modern
	 * kernels spell it the other way round (MIPI_DSI_MODE_NO_EOT_PACKET),
	 * so sending EOT packets is now the default and nothing is needed here.
	 */
	dsi->mode_flags = MIPI_DSI_MODE_VIDEO |
			  MIPI_DSI_CLOCK_NON_CONTINUOUS;

	jdi = devm_drm_panel_alloc(&dsi->dev, __typeof(*jdi), base,
				   &jdi_panel_funcs, DRM_MODE_CONNECTOR_DSI);
	if (IS_ERR(jdi))
		return PTR_ERR(jdi);

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

	ret = jdi_panel_add(jdi);
	if (ret < 0)
		return ret;

	ret = mipi_dsi_attach(dsi);
	if (ret < 0) {
		jdi_panel_del(jdi);
		return ret;
	}

	return 0;
}

static void jdi_panel_remove(struct mipi_dsi_device *dsi)
{
	struct jdi_panel *jdi = 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);

	jdi_panel_del(jdi);
}

static void jdi_panel_shutdown(struct mipi_dsi_device *dsi)
{
	struct jdi_panel *jdi = mipi_dsi_get_drvdata(dsi);

	jdi_panel_disable(&jdi->base);
}

static const struct of_device_id jdi_of_match[] = {
	{ .compatible = "jdi,lpm062m326a" },
	{ }
};
MODULE_DEVICE_TABLE(of, jdi_of_match);

static struct mipi_dsi_driver jdi_panel_driver = {
	.driver = {
		.name = "panel-jdi-lpm062m326a",
		.of_match_table = jdi_of_match,
	},
	.probe = jdi_panel_probe,
	.remove = jdi_panel_remove,
	.shutdown = jdi_panel_shutdown,
};
module_mipi_dsi_driver(jdi_panel_driver);

MODULE_AUTHOR("SwtcR <swtcr0@gmail.com>");
MODULE_DESCRIPTION("JDI LPM062M326A (720x1280) panel driver");
MODULE_LICENSE("GPL");