drivers/gpu/drm/panel/panel-jdi-lt070me05000.c - third_party/dump-capture-kernel - Git at Google

 /*
  * Copyright (C) 2016 InforceComputing
  * Author: Vinay Simha BN <simhavcs@gmail.com>
  *
  * Copyright (C) 2016 Linaro Ltd
  * Author: Sumit Semwal <sumit.semwal@linaro.org>
  *
  * From internet archives, the panel for Nexus 7 2nd Gen, 2013 model is a
  * JDI model LT070ME05000, and its data sheet is at:
  * http://panelone.net/en/7-0-inch/JDI_LT070ME05000_7.0_inch-datasheet
  *
  * This program is free software; you can redistribute it and/or modify it
  * under the terms of the GNU General Public License version 2 as published by
  * the Free Software Foundation.
  *
  * This program is distributed in the hope that it will be useful, but WITHOUT
  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
  * more details.
  *
  * You should have received a copy of the GNU General Public License along with
  * this program.  If not, see <http://www.gnu.org/licenses/>.
  */
 #include <linux/backlight.h>
 #include <linux/gpio/consumer.h>
 #include <linux/module.h>
 #include <linux/of.h>
 #include <linux/regulator/consumer.h>

 #include <drm/drmP.h>
 #include <drm/drm_crtc.h>
 #include <drm/drm_mipi_dsi.h>
 #include <drm/drm_panel.h>

 #include <video/mipi_display.h>

 static const char * const regulator_names[] = {
 	"vddp",
 	"iovcc"
 };

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

 	struct regulator_bulk_data supplies[ARRAY_SIZE(regulator_names)];

 	struct gpio_desc *enable_gpio;
 	struct gpio_desc *reset_gpio;
 	struct gpio_desc *dcdc_en_gpio;
 	struct backlight_device *backlight;

 	bool prepared;
 	bool enabled;

 	const struct drm_display_mode *mode;
 };

 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;
 	struct device *dev = &jdi->dsi->dev;
 	int ret;

 	dsi->mode_flags |= MIPI_DSI_MODE_LPM;

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

 	usleep_range(10000, 20000);

 	ret = mipi_dsi_dcs_set_pixel_format(dsi, MIPI_DCS_PIXEL_FMT_24BIT << 4);
 	if (ret < 0) {
 		dev_err(dev, "failed to set pixel format: %d\n", ret);
 		return ret;
 	}

 	ret = mipi_dsi_dcs_set_column_address(dsi, 0, jdi->mode->hdisplay - 1);
 	if (ret < 0) {
 		dev_err(dev, "failed to set column address: %d\n", ret);
 		return ret;
 	}

 	ret = mipi_dsi_dcs_set_page_address(dsi, 0, jdi->mode->vdisplay - 1);
 	if (ret < 0) {
 		dev_err(dev, "failed to set page address: %d\n", ret);
 		return ret;
 	}

 	/*
 	 * BIT(5) BCTRL = 1 Backlight Control Block On, Brightness registers
 	 *                  are active
 	 * BIT(3) BL = 1    Backlight Control On
 	 * BIT(2) DD = 0    Display Dimming is Off
 	 */
 	ret = mipi_dsi_dcs_write(dsi, MIPI_DCS_WRITE_CONTROL_DISPLAY,
 				 (u8[]){ 0x24 }, 1);
 	if (ret < 0) {
 		dev_err(dev, "failed to write control display: %d\n", ret);
 		return ret;
 	}

 	/* CABC off */
 	ret = mipi_dsi_dcs_write(dsi, MIPI_DCS_WRITE_POWER_SAVE,
 				 (u8[]){ 0x00 }, 1);
 	if (ret < 0) {
 		dev_err(dev, "failed to set cabc off: %d\n", ret);
 		return ret;
 	}

 	ret = mipi_dsi_dcs_exit_sleep_mode(dsi);
 	if (ret < 0) {
 		dev_err(dev, "failed to set exit sleep mode: %d\n", ret);
 		return ret;
 	}

 	msleep(120);

 	ret = mipi_dsi_generic_write(dsi, (u8[]){0xB0, 0x00}, 2);
 	if (ret < 0) {
 		dev_err(dev, "failed to set mcap: %d\n", ret);
 		return ret;
 	}

 	mdelay(10);

 	/* Interface setting, video mode */
 	ret = mipi_dsi_generic_write(dsi, (u8[])
 				     {0xB3, 0x26, 0x08, 0x00, 0x20, 0x00}, 6);
 	if (ret < 0) {
 		dev_err(dev, "failed to set display interface setting: %d\n"
 			, ret);
 		return ret;
 	}

 	mdelay(20);

 	ret = mipi_dsi_generic_write(dsi, (u8[]){0xB0, 0x03}, 2);
 	if (ret < 0) {
 		dev_err(dev, "failed to set default values for mcap: %d\n"
 			, ret);
 		return ret;
 	}

 	return 0;
 }

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

 	dsi->mode_flags |= MIPI_DSI_MODE_LPM;

 	ret = mipi_dsi_dcs_set_display_on(dsi);
 	if (ret < 0)
 		dev_err(dev, "failed to set display on: %d\n", ret);

 	return ret;
 }

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

 	dsi->mode_flags &= ~MIPI_DSI_MODE_LPM;

 	ret = mipi_dsi_dcs_set_display_off(dsi);
 	if (ret < 0)
 		dev_err(dev, "failed to set display off: %d\n", ret);

 	ret = mipi_dsi_dcs_enter_sleep_mode(dsi);
 	if (ret < 0)
 		dev_err(dev, "failed to enter sleep mode: %d\n", ret);

 	msleep(100);
 }

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

 	if (!jdi->enabled)
 		return 0;

 	jdi->backlight->props.power = FB_BLANK_POWERDOWN;
 	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);
 	struct device *dev = &jdi->dsi->dev;
 	int ret;

 	if (!jdi->prepared)
 		return 0;

 	jdi_panel_off(jdi);

 	ret = regulator_bulk_disable(ARRAY_SIZE(jdi->supplies), jdi->supplies);
 	if (ret < 0)
 		dev_err(dev, "regulator disable failed, %d\n", ret);

 	gpiod_set_value(jdi->enable_gpio, 0);

 	gpiod_set_value(jdi->reset_gpio, 1);

 	gpiod_set_value(jdi->dcdc_en_gpio, 0);

 	jdi->prepared = false;

 	return 0;
 }

 static int jdi_panel_prepare(struct drm_panel *panel)
 {
 	struct jdi_panel *jdi = to_jdi_panel(panel);
 	struct device *dev = &jdi->dsi->dev;
 	int ret;

 	if (jdi->prepared)
 		return 0;

 	ret = regulator_bulk_enable(ARRAY_SIZE(jdi->supplies), jdi->supplies);
 	if (ret < 0) {
 		dev_err(dev, "regulator enable failed, %d\n", ret);
 		return ret;
 	}

 	msleep(20);

 	gpiod_set_value(jdi->dcdc_en_gpio, 1);
 	usleep_range(10, 20);

 	gpiod_set_value(jdi->reset_gpio, 0);
 	usleep_range(10, 20);

 	gpiod_set_value(jdi->enable_gpio, 1);
 	usleep_range(10, 20);

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

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

 	jdi->prepared = true;

 	return 0;

 poweroff:
 	ret = regulator_bulk_disable(ARRAY_SIZE(jdi->supplies), jdi->supplies);
 	if (ret < 0)
 		dev_err(dev, "regulator disable failed, %d\n", ret);

 	gpiod_set_value(jdi->enable_gpio, 0);

 	gpiod_set_value(jdi->reset_gpio, 1);

 	gpiod_set_value(jdi->dcdc_en_gpio, 0);

 	return ret;
 }

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

 	if (jdi->enabled)
 		return 0;

 	jdi->backlight->props.power = FB_BLANK_UNBLANK;
 	backlight_update_status(jdi->backlight);

 	jdi->enabled = true;

 	return 0;
 }

 static const struct drm_display_mode default_mode = {
 		.clock = 155493,
 		.hdisplay = 1200,
 		.hsync_start = 1200 + 48,
 		.hsync_end = 1200 + 48 + 32,
 		.htotal = 1200 + 48 + 32 + 60,
 		.vdisplay = 1920,
 		.vsync_start = 1920 + 3,
 		.vsync_end = 1920 + 3 + 5,
 		.vtotal = 1920 + 3 + 5 + 6,
 		.vrefresh = 60,
 		.flags = 0,
 };

 static int jdi_panel_get_modes(struct drm_panel *panel)
 {
 	struct drm_display_mode *mode;
 	struct jdi_panel *jdi = to_jdi_panel(panel);
 	struct device *dev = &jdi->dsi->dev;

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

 	drm_mode_set_name(mode);

 	drm_mode_probed_add(panel->connector, mode);

 	panel->connector->display_info.width_mm = 95;
 	panel->connector->display_info.height_mm = 151;

 	return 1;
 }

 static int dsi_dcs_bl_get_brightness(struct backlight_device *bl)
 {
 	struct mipi_dsi_device *dsi = bl_get_data(bl);
 	int ret;
 	u16 brightness = bl->props.brightness;

 	dsi->mode_flags &= ~MIPI_DSI_MODE_LPM;

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

 	dsi->mode_flags |= MIPI_DSI_MODE_LPM;

 	return brightness & 0xff;
 }

 static int dsi_dcs_bl_update_status(struct backlight_device *bl)
 {
 	struct mipi_dsi_device *dsi = bl_get_data(bl);
 	int ret;

 	dsi->mode_flags &= ~MIPI_DSI_MODE_LPM;

 	ret = mipi_dsi_dcs_set_display_brightness(dsi, bl->props.brightness);
 	if (ret < 0)
 		return ret;

 	dsi->mode_flags |= MIPI_DSI_MODE_LPM;

 	return 0;
 }

 static const struct backlight_ops dsi_bl_ops = {
 	.update_status = dsi_dcs_bl_update_status,
 	.get_brightness = dsi_dcs_bl_get_brightness,
 };

 static struct backlight_device *
 drm_panel_create_dsi_backlight(struct mipi_dsi_device *dsi)
 {
 	struct device *dev = &dsi->dev;
 	struct backlight_properties props;

 	memset(&props, 0, sizeof(props));
 	props.type = BACKLIGHT_RAW;
 	props.brightness = 255;
 	props.max_brightness = 255;

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

 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 const struct of_device_id jdi_of_match[] = {
 	{ .compatible = "jdi,lt070me05000", },
 	{ }
 };
 MODULE_DEVICE_TABLE(of, jdi_of_match);

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

 	jdi->mode = &default_mode;

 	for (i = 0; i < ARRAY_SIZE(jdi->supplies); i++)
 		jdi->supplies[i].supply = regulator_names[i];

 	ret = devm_regulator_bulk_get(dev, ARRAY_SIZE(jdi->supplies),
 				      jdi->supplies);
 	if (ret < 0) {
 		dev_err(dev, "failed to init regulator, ret=%d\n", ret);
 		return ret;
 	}

 	jdi->enable_gpio = devm_gpiod_get(dev, "enable", GPIOD_OUT_LOW);
 	if (IS_ERR(jdi->enable_gpio)) {
 		ret = PTR_ERR(jdi->enable_gpio);
 		dev_err(dev, "cannot get enable-gpio %d\n", ret);
 		return ret;
 	}

 	jdi->reset_gpio = devm_gpiod_get(dev, "reset", GPIOD_OUT_HIGH);
 	if (IS_ERR(jdi->reset_gpio)) {
 		ret = PTR_ERR(jdi->reset_gpio);
 		dev_err(dev, "cannot get reset-gpios %d\n", ret);
 		return ret;
 	}

 	jdi->dcdc_en_gpio = devm_gpiod_get(dev, "dcdc-en", GPIOD_OUT_LOW);
 	if (IS_ERR(jdi->dcdc_en_gpio)) {
 		ret = PTR_ERR(jdi->dcdc_en_gpio);
 		dev_err(dev, "cannot get dcdc-en-gpio %d\n", ret);
 		return ret;
 	}

 	jdi->backlight = drm_panel_create_dsi_backlight(jdi->dsi);
 	if (IS_ERR(jdi->backlight)) {
 		ret = PTR_ERR(jdi->backlight);
 		dev_err(dev, "failed to register backlight %d\n", ret);
 		return ret;
 	}

 	drm_panel_init(&jdi->base);
 	jdi->base.funcs = &jdi_panel_funcs;
 	jdi->base.dev = &jdi->dsi->dev;

 	ret = drm_panel_add(&jdi->base);

 	return ret;
 }

 static void jdi_panel_del(struct jdi_panel *jdi)
 {
 	if (jdi->base.dev)
 		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;
 	dsi->mode_flags =  MIPI_DSI_MODE_VIDEO_HSE | MIPI_DSI_MODE_VIDEO |
 			   MIPI_DSI_CLOCK_NON_CONTINUOUS;

 	jdi = devm_kzalloc(&dsi->dev, sizeof(*jdi), GFP_KERNEL);
 	if (!jdi)
 		return -ENOMEM;

 	mipi_dsi_set_drvdata(dsi, jdi);

 	jdi->dsi = dsi;

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

 	return mipi_dsi_attach(dsi);
 }

 static int jdi_panel_remove(struct mipi_dsi_device *dsi)
 {
 	struct jdi_panel *jdi = mipi_dsi_get_drvdata(dsi);
 	int ret;

 	ret = jdi_panel_disable(&jdi->base);
 	if (ret < 0)
 		dev_err(&dsi->dev, "failed to disable panel: %d\n", 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);

 	return 0;
 }

 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 struct mipi_dsi_driver jdi_panel_driver = {
 	.driver = {
 		.name = "panel-jdi-lt070me05000",
 		.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("Sumit Semwal <sumit.semwal@linaro.org>");
 MODULE_AUTHOR("Vinay Simha BN <simhavcs@gmail.com>");
 MODULE_DESCRIPTION("JDI LT070ME05000 WUXGA");
 MODULE_LICENSE("GPL v2");
	/*
	* Copyright (C) 2016 InforceComputing
	* Author: Vinay Simha BN <simhavcs@gmail.com>
	*
	* Copyright (C) 2016 Linaro Ltd
	* Author: Sumit Semwal <sumit.semwal@linaro.org>
	*
	* From internet archives, the panel for Nexus 7 2nd Gen, 2013 model is a
	* JDI model LT070ME05000, and its data sheet is at:
	* http://panelone.net/en/7-0-inch/JDI_LT070ME05000_7.0_inch-datasheet
	*
	* This program is free software; you can redistribute it and/or modify it
	* under the terms of the GNU General Public License version 2 as published by
	* the Free Software Foundation.
	*
	* This program is distributed in the hope that it will be useful, but WITHOUT
	* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
	* FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
	* more details.
	*
	* You should have received a copy of the GNU General Public License along with
	* this program. If not, see <http://www.gnu.org/licenses/>.
	*/
	#include <linux/backlight.h>
	#include <linux/gpio/consumer.h>
	#include <linux/module.h>
	#include <linux/of.h>
	#include <linux/regulator/consumer.h>

	#include <drm/drmP.h>
	#include <drm/drm_crtc.h>
	#include <drm/drm_mipi_dsi.h>
	#include <drm/drm_panel.h>

	#include <video/mipi_display.h>

	static const char * const regulator_names[] = {
	"vddp",
	"iovcc"
	};

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

	struct regulator_bulk_data supplies[ARRAY_SIZE(regulator_names)];

	struct gpio_desc *enable_gpio;
	struct gpio_desc *reset_gpio;
	struct gpio_desc *dcdc_en_gpio;
	struct backlight_device *backlight;

	bool prepared;
	bool enabled;

	const struct drm_display_mode *mode;
	};

	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;
	struct device *dev = &jdi->dsi->dev;
	int ret;

	dsi->mode_flags \|= MIPI_DSI_MODE_LPM;

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

	usleep_range(10000, 20000);

	ret = mipi_dsi_dcs_set_pixel_format(dsi, MIPI_DCS_PIXEL_FMT_24BIT << 4);
	if (ret < 0) {
	dev_err(dev, "failed to set pixel format: %d\n", ret);
	return ret;
	}

	ret = mipi_dsi_dcs_set_column_address(dsi, 0, jdi->mode->hdisplay - 1);
	if (ret < 0) {
	dev_err(dev, "failed to set column address: %d\n", ret);
	return ret;
	}

	ret = mipi_dsi_dcs_set_page_address(dsi, 0, jdi->mode->vdisplay - 1);
	if (ret < 0) {
	dev_err(dev, "failed to set page address: %d\n", ret);
	return ret;
	}

	/*
	* BIT(5) BCTRL = 1 Backlight Control Block On, Brightness registers
	* are active
	* BIT(3) BL = 1 Backlight Control On
	* BIT(2) DD = 0 Display Dimming is Off
	*/
	ret = mipi_dsi_dcs_write(dsi, MIPI_DCS_WRITE_CONTROL_DISPLAY,
	(u8[]){ 0x24 }, 1);
	if (ret < 0) {
	dev_err(dev, "failed to write control display: %d\n", ret);
	return ret;
	}

	/* CABC off */
	ret = mipi_dsi_dcs_write(dsi, MIPI_DCS_WRITE_POWER_SAVE,
	(u8[]){ 0x00 }, 1);
	if (ret < 0) {
	dev_err(dev, "failed to set cabc off: %d\n", ret);
	return ret;
	}

	ret = mipi_dsi_dcs_exit_sleep_mode(dsi);
	if (ret < 0) {
	dev_err(dev, "failed to set exit sleep mode: %d\n", ret);
	return ret;
	}

	msleep(120);

	ret = mipi_dsi_generic_write(dsi, (u8[]){0xB0, 0x00}, 2);
	if (ret < 0) {
	dev_err(dev, "failed to set mcap: %d\n", ret);
	return ret;
	}

	mdelay(10);

	/* Interface setting, video mode */
	ret = mipi_dsi_generic_write(dsi, (u8[])
	{0xB3, 0x26, 0x08, 0x00, 0x20, 0x00}, 6);
	if (ret < 0) {
	dev_err(dev, "failed to set display interface setting: %d\n"
	, ret);
	return ret;
	}

	mdelay(20);

	ret = mipi_dsi_generic_write(dsi, (u8[]){0xB0, 0x03}, 2);
	if (ret < 0) {
	dev_err(dev, "failed to set default values for mcap: %d\n"
	, ret);
	return ret;
	}

	return 0;
	}

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

	dsi->mode_flags \|= MIPI_DSI_MODE_LPM;

	ret = mipi_dsi_dcs_set_display_on(dsi);
	if (ret < 0)
	dev_err(dev, "failed to set display on: %d\n", ret);

	return ret;
	}

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

	dsi->mode_flags &= ~MIPI_DSI_MODE_LPM;

	ret = mipi_dsi_dcs_set_display_off(dsi);
	if (ret < 0)
	dev_err(dev, "failed to set display off: %d\n", ret);

	ret = mipi_dsi_dcs_enter_sleep_mode(dsi);
	if (ret < 0)
	dev_err(dev, "failed to enter sleep mode: %d\n", ret);

	msleep(100);
	}

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

	if (!jdi->enabled)
	return 0;

	jdi->backlight->props.power = FB_BLANK_POWERDOWN;
	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);
	struct device *dev = &jdi->dsi->dev;
	int ret;

	if (!jdi->prepared)
	return 0;

	jdi_panel_off(jdi);

	ret = regulator_bulk_disable(ARRAY_SIZE(jdi->supplies), jdi->supplies);
	if (ret < 0)
	dev_err(dev, "regulator disable failed, %d\n", ret);

	gpiod_set_value(jdi->enable_gpio, 0);

	gpiod_set_value(jdi->reset_gpio, 1);

	gpiod_set_value(jdi->dcdc_en_gpio, 0);

	jdi->prepared = false;

	return 0;
	}

	static int jdi_panel_prepare(struct drm_panel *panel)
	{
	struct jdi_panel *jdi = to_jdi_panel(panel);
	struct device *dev = &jdi->dsi->dev;
	int ret;

	if (jdi->prepared)
	return 0;

	ret = regulator_bulk_enable(ARRAY_SIZE(jdi->supplies), jdi->supplies);
	if (ret < 0) {
	dev_err(dev, "regulator enable failed, %d\n", ret);
	return ret;
	}

	msleep(20);

	gpiod_set_value(jdi->dcdc_en_gpio, 1);
	usleep_range(10, 20);

	gpiod_set_value(jdi->reset_gpio, 0);
	usleep_range(10, 20);

	gpiod_set_value(jdi->enable_gpio, 1);
	usleep_range(10, 20);

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

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

	jdi->prepared = true;

	return 0;

	poweroff:
	ret = regulator_bulk_disable(ARRAY_SIZE(jdi->supplies), jdi->supplies);
	if (ret < 0)
	dev_err(dev, "regulator disable failed, %d\n", ret);

	gpiod_set_value(jdi->enable_gpio, 0);

	gpiod_set_value(jdi->reset_gpio, 1);

	gpiod_set_value(jdi->dcdc_en_gpio, 0);

	return ret;
	}

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

	if (jdi->enabled)
	return 0;

	jdi->backlight->props.power = FB_BLANK_UNBLANK;
	backlight_update_status(jdi->backlight);

	jdi->enabled = true;

	return 0;
	}

	static const struct drm_display_mode default_mode = {
	.clock = 155493,
	.hdisplay = 1200,
	.hsync_start = 1200 + 48,
	.hsync_end = 1200 + 48 + 32,
	.htotal = 1200 + 48 + 32 + 60,
	.vdisplay = 1920,
	.vsync_start = 1920 + 3,
	.vsync_end = 1920 + 3 + 5,
	.vtotal = 1920 + 3 + 5 + 6,
	.vrefresh = 60,
	.flags = 0,
	};

	static int jdi_panel_get_modes(struct drm_panel *panel)
	{
	struct drm_display_mode *mode;
	struct jdi_panel *jdi = to_jdi_panel(panel);
	struct device *dev = &jdi->dsi->dev;

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

	drm_mode_set_name(mode);

	drm_mode_probed_add(panel->connector, mode);

	panel->connector->display_info.width_mm = 95;
	panel->connector->display_info.height_mm = 151;

	return 1;
	}

	static int dsi_dcs_bl_get_brightness(struct backlight_device *bl)
	{
	struct mipi_dsi_device *dsi = bl_get_data(bl);
	int ret;
	u16 brightness = bl->props.brightness;

	dsi->mode_flags &= ~MIPI_DSI_MODE_LPM;

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

	dsi->mode_flags \|= MIPI_DSI_MODE_LPM;

	return brightness & 0xff;
	}

	static int dsi_dcs_bl_update_status(struct backlight_device *bl)
	{
	struct mipi_dsi_device *dsi = bl_get_data(bl);
	int ret;

	dsi->mode_flags &= ~MIPI_DSI_MODE_LPM;

	ret = mipi_dsi_dcs_set_display_brightness(dsi, bl->props.brightness);
	if (ret < 0)
	return ret;

	dsi->mode_flags \|= MIPI_DSI_MODE_LPM;

	return 0;
	}

	static const struct backlight_ops dsi_bl_ops = {
	.update_status = dsi_dcs_bl_update_status,
	.get_brightness = dsi_dcs_bl_get_brightness,
	};

	static struct backlight_device *
	drm_panel_create_dsi_backlight(struct mipi_dsi_device *dsi)
	{
	struct device *dev = &dsi->dev;
	struct backlight_properties props;

	memset(&props, 0, sizeof(props));
	props.type = BACKLIGHT_RAW;
	props.brightness = 255;
	props.max_brightness = 255;

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

	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 const struct of_device_id jdi_of_match[] = {
	{ .compatible = "jdi,lt070me05000", },
	{ }
	};
	MODULE_DEVICE_TABLE(of, jdi_of_match);

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

	jdi->mode = &default_mode;

	for (i = 0; i < ARRAY_SIZE(jdi->supplies); i++)
	jdi->supplies[i].supply = regulator_names[i];

	ret = devm_regulator_bulk_get(dev, ARRAY_SIZE(jdi->supplies),
	jdi->supplies);
	if (ret < 0) {
	dev_err(dev, "failed to init regulator, ret=%d\n", ret);
	return ret;
	}

	jdi->enable_gpio = devm_gpiod_get(dev, "enable", GPIOD_OUT_LOW);
	if (IS_ERR(jdi->enable_gpio)) {
	ret = PTR_ERR(jdi->enable_gpio);
	dev_err(dev, "cannot get enable-gpio %d\n", ret);
	return ret;
	}

	jdi->reset_gpio = devm_gpiod_get(dev, "reset", GPIOD_OUT_HIGH);
	if (IS_ERR(jdi->reset_gpio)) {
	ret = PTR_ERR(jdi->reset_gpio);
	dev_err(dev, "cannot get reset-gpios %d\n", ret);
	return ret;
	}

	jdi->dcdc_en_gpio = devm_gpiod_get(dev, "dcdc-en", GPIOD_OUT_LOW);
	if (IS_ERR(jdi->dcdc_en_gpio)) {
	ret = PTR_ERR(jdi->dcdc_en_gpio);
	dev_err(dev, "cannot get dcdc-en-gpio %d\n", ret);
	return ret;
	}

	jdi->backlight = drm_panel_create_dsi_backlight(jdi->dsi);
	if (IS_ERR(jdi->backlight)) {
	ret = PTR_ERR(jdi->backlight);
	dev_err(dev, "failed to register backlight %d\n", ret);
	return ret;
	}

	drm_panel_init(&jdi->base);
	jdi->base.funcs = &jdi_panel_funcs;
	jdi->base.dev = &jdi->dsi->dev;

	ret = drm_panel_add(&jdi->base);

	return ret;
	}

	static void jdi_panel_del(struct jdi_panel *jdi)
	{
	if (jdi->base.dev)
	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;
	dsi->mode_flags = MIPI_DSI_MODE_VIDEO_HSE \| MIPI_DSI_MODE_VIDEO \|
	MIPI_DSI_CLOCK_NON_CONTINUOUS;

	jdi = devm_kzalloc(&dsi->dev, sizeof(*jdi), GFP_KERNEL);
	if (!jdi)
	return -ENOMEM;

	mipi_dsi_set_drvdata(dsi, jdi);

	jdi->dsi = dsi;

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

	return mipi_dsi_attach(dsi);
	}

	static int jdi_panel_remove(struct mipi_dsi_device *dsi)
	{
	struct jdi_panel *jdi = mipi_dsi_get_drvdata(dsi);
	int ret;

	ret = jdi_panel_disable(&jdi->base);
	if (ret < 0)
	dev_err(&dsi->dev, "failed to disable panel: %d\n", 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);

	return 0;
	}

	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 struct mipi_dsi_driver jdi_panel_driver = {
	.driver = {
	.name = "panel-jdi-lt070me05000",
	.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("Sumit Semwal <sumit.semwal@linaro.org>");
	MODULE_AUTHOR("Vinay Simha BN <simhavcs@gmail.com>");
	MODULE_DESCRIPTION("JDI LT070ME05000 WUXGA");
	MODULE_LICENSE("GPL v2");