drivers/gpu/drm/panel/panel-lvds.c - third_party/linux - Git at Google

 /*
  * Generic LVDS panel driver
  *
  * Copyright (C) 2016 Laurent Pinchart
  * Copyright (C) 2016 Renesas Electronics Corporation
  *
  * Contact: Laurent Pinchart (laurent.pinchart@ideasonboard.com)
  *
  * This program is free software; you can redistribute it and/or modify
  * it under the terms of the GNU General Public License as published by
  * the Free Software Foundation; either version 2 of the License, or
  * (at your option) any later version.
  */

 #include <linux/backlight.h>
 #include <linux/gpio/consumer.h>
 #include <linux/module.h>
 #include <linux/of_platform.h>
 #include <linux/platform_device.h>
 #include <linux/regulator/consumer.h>
 #include <linux/slab.h>

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

 #include <video/display_timing.h>
 #include <video/of_display_timing.h>
 #include <video/videomode.h>

 struct panel_lvds {
 	struct drm_panel panel;
 	struct device *dev;

 	const char *label;
 	unsigned int width;
 	unsigned int height;
 	struct videomode video_mode;
 	unsigned int bus_format;
 	bool data_mirror;

 	struct backlight_device *backlight;
 	struct regulator *supply;

 	struct gpio_desc *enable_gpio;
 	struct gpio_desc *reset_gpio;
 };

 static inline struct panel_lvds *to_panel_lvds(struct drm_panel *panel)
 {
 	return container_of(panel, struct panel_lvds, panel);
 }

 static int panel_lvds_disable(struct drm_panel *panel)
 {
 	struct panel_lvds *lvds = to_panel_lvds(panel);

 	if (lvds->backlight) {
 		lvds->backlight->props.power = FB_BLANK_POWERDOWN;
 		lvds->backlight->props.state |= BL_CORE_FBBLANK;
 		backlight_update_status(lvds->backlight);
 	}

 	return 0;
 }

 static int panel_lvds_unprepare(struct drm_panel *panel)
 {
 	struct panel_lvds *lvds = to_panel_lvds(panel);

 	if (lvds->enable_gpio)
 		gpiod_set_value_cansleep(lvds->enable_gpio, 0);

 	if (lvds->supply)
 		regulator_disable(lvds->supply);

 	return 0;
 }

 static int panel_lvds_prepare(struct drm_panel *panel)
 {
 	struct panel_lvds *lvds = to_panel_lvds(panel);

 	if (lvds->supply) {
 		int err;

 		err = regulator_enable(lvds->supply);
 		if (err < 0) {
 			dev_err(lvds->dev, "failed to enable supply: %d\n",
 				err);
 			return err;
 		}
 	}

 	if (lvds->enable_gpio)
 		gpiod_set_value_cansleep(lvds->enable_gpio, 1);

 	return 0;
 }

 static int panel_lvds_enable(struct drm_panel *panel)
 {
 	struct panel_lvds *lvds = to_panel_lvds(panel);

 	if (lvds->backlight) {
 		lvds->backlight->props.state &= ~BL_CORE_FBBLANK;
 		lvds->backlight->props.power = FB_BLANK_UNBLANK;
 		backlight_update_status(lvds->backlight);
 	}

 	return 0;
 }

 static int panel_lvds_get_modes(struct drm_panel *panel)
 {
 	struct panel_lvds *lvds = to_panel_lvds(panel);
 	struct drm_connector *connector = lvds->panel.connector;
 	struct drm_display_mode *mode;

 	mode = drm_mode_create(lvds->panel.drm);
 	if (!mode)
 		return 0;

 	drm_display_mode_from_videomode(&lvds->video_mode, mode);
 	mode->type |= DRM_MODE_TYPE_DRIVER | DRM_MODE_TYPE_PREFERRED;
 	drm_mode_probed_add(connector, mode);

 	connector->display_info.width_mm = lvds->width;
 	connector->display_info.height_mm = lvds->height;
 	drm_display_info_set_bus_formats(&connector->display_info,
 					 &lvds->bus_format, 1);
 	connector->display_info.bus_flags = lvds->data_mirror
 					  ? DRM_BUS_FLAG_DATA_LSB_TO_MSB
 					  : DRM_BUS_FLAG_DATA_MSB_TO_LSB;

 	return 1;
 }

 static const struct drm_panel_funcs panel_lvds_funcs = {
 	.disable = panel_lvds_disable,
 	.unprepare = panel_lvds_unprepare,
 	.prepare = panel_lvds_prepare,
 	.enable = panel_lvds_enable,
 	.get_modes = panel_lvds_get_modes,
 };

 static int panel_lvds_parse_dt(struct panel_lvds *lvds)
 {
 	struct device_node *np = lvds->dev->of_node;
 	struct display_timing timing;
 	const char *mapping;
 	int ret;

 	ret = of_get_display_timing(np, "panel-timing", &timing);
 	if (ret < 0)
 		return ret;

 	videomode_from_timing(&timing, &lvds->video_mode);

 	ret = of_property_read_u32(np, "width-mm", &lvds->width);
 	if (ret < 0) {
 		dev_err(lvds->dev, "%pOF: invalid or missing %s DT property\n",
 			np, "width-mm");
 		return -ENODEV;
 	}
 	ret = of_property_read_u32(np, "height-mm", &lvds->height);
 	if (ret < 0) {
 		dev_err(lvds->dev, "%pOF: invalid or missing %s DT property\n",
 			np, "height-mm");
 		return -ENODEV;
 	}

 	of_property_read_string(np, "label", &lvds->label);

 	ret = of_property_read_string(np, "data-mapping", &mapping);
 	if (ret < 0) {
 		dev_err(lvds->dev, "%pOF: invalid or missing %s DT property\n",
 			np, "data-mapping");
 		return -ENODEV;
 	}

 	if (!strcmp(mapping, "jeida-18")) {
 		lvds->bus_format = MEDIA_BUS_FMT_RGB666_1X7X3_SPWG;
 	} else if (!strcmp(mapping, "jeida-24")) {
 		lvds->bus_format = MEDIA_BUS_FMT_RGB888_1X7X4_JEIDA;
 	} else if (!strcmp(mapping, "vesa-24")) {
 		lvds->bus_format = MEDIA_BUS_FMT_RGB888_1X7X4_SPWG;
 	} else {
 		dev_err(lvds->dev, "%pOF: invalid or missing %s DT property\n",
 			np, "data-mapping");
 		return -EINVAL;
 	}

 	lvds->data_mirror = of_property_read_bool(np, "data-mirror");

 	return 0;
 }

 static int panel_lvds_probe(struct platform_device *pdev)
 {
 	struct panel_lvds *lvds;
 	struct device_node *np;
 	int ret;

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

 	lvds->dev = &pdev->dev;

 	ret = panel_lvds_parse_dt(lvds);
 	if (ret < 0)
 		return ret;

 	lvds->supply = devm_regulator_get_optional(lvds->dev, "power");
 	if (IS_ERR(lvds->supply)) {
 		ret = PTR_ERR(lvds->supply);

 		if (ret != -ENODEV) {
 			if (ret != -EPROBE_DEFER)
 				dev_err(lvds->dev, "failed to request regulator: %d\n",
 					ret);
 			return ret;
 		}

 		lvds->supply = NULL;
 	}

 	/* Get GPIOs and backlight controller. */
 	lvds->enable_gpio = devm_gpiod_get_optional(lvds->dev, "enable",
 						     GPIOD_OUT_LOW);
 	if (IS_ERR(lvds->enable_gpio)) {
 		ret = PTR_ERR(lvds->enable_gpio);
 		dev_err(lvds->dev, "failed to request %s GPIO: %d\n",
 			"enable", ret);
 		return ret;
 	}

 	lvds->reset_gpio = devm_gpiod_get_optional(lvds->dev, "reset",
 						     GPIOD_OUT_HIGH);
 	if (IS_ERR(lvds->reset_gpio)) {
 		ret = PTR_ERR(lvds->reset_gpio);
 		dev_err(lvds->dev, "failed to request %s GPIO: %d\n",
 			"reset", ret);
 		return ret;
 	}

 	np = of_parse_phandle(lvds->dev->of_node, "backlight", 0);
 	if (np) {
 		lvds->backlight = of_find_backlight_by_node(np);
 		of_node_put(np);

 		if (!lvds->backlight)
 			return -EPROBE_DEFER;
 	}

 	/*
 	 * TODO: Handle all power supplies specified in the DT node in a generic
 	 * way for panels that don't care about power supply ordering. LVDS
 	 * panels that require a specific power sequence will need a dedicated
 	 * driver.
 	 */

 	/* Register the panel. */
 	drm_panel_init(&lvds->panel);
 	lvds->panel.dev = lvds->dev;
 	lvds->panel.funcs = &panel_lvds_funcs;

 	ret = drm_panel_add(&lvds->panel);
 	if (ret < 0)
 		goto error;

 	dev_set_drvdata(lvds->dev, lvds);
 	return 0;

 error:
 	put_device(&lvds->backlight->dev);
 	return ret;
 }

 static int panel_lvds_remove(struct platform_device *pdev)
 {
 	struct panel_lvds *lvds = dev_get_drvdata(&pdev->dev);

 	drm_panel_detach(&lvds->panel);
 	drm_panel_remove(&lvds->panel);

 	panel_lvds_disable(&lvds->panel);

 	if (lvds->backlight)
 		put_device(&lvds->backlight->dev);

 	return 0;
 }

 static const struct of_device_id panel_lvds_of_table[] = {
 	{ .compatible = "panel-lvds", },
 	{ /* Sentinel */ },
 };

 MODULE_DEVICE_TABLE(of, panel_lvds_of_table);

 static struct platform_driver panel_lvds_driver = {
 	.probe		= panel_lvds_probe,
 	.remove		= panel_lvds_remove,
 	.driver		= {
 		.name	= "panel-lvds",
 		.of_match_table = panel_lvds_of_table,
 	},
 };

 module_platform_driver(panel_lvds_driver);

 MODULE_AUTHOR("Laurent Pinchart <laurent.pinchart@ideasonboard.com>");
 MODULE_DESCRIPTION("LVDS Panel Driver");
 MODULE_LICENSE("GPL");
	/*
	* Generic LVDS panel driver
	*
	* Copyright (C) 2016 Laurent Pinchart
	* Copyright (C) 2016 Renesas Electronics Corporation
	*
	* Contact: Laurent Pinchart (laurent.pinchart@ideasonboard.com)
	*
	* This program is free software; you can redistribute it and/or modify
	* it under the terms of the GNU General Public License as published by
	* the Free Software Foundation; either version 2 of the License, or
	* (at your option) any later version.
	*/

	#include <linux/backlight.h>
	#include <linux/gpio/consumer.h>
	#include <linux/module.h>
	#include <linux/of_platform.h>
	#include <linux/platform_device.h>
	#include <linux/regulator/consumer.h>
	#include <linux/slab.h>

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

	#include <video/display_timing.h>
	#include <video/of_display_timing.h>
	#include <video/videomode.h>

	struct panel_lvds {
	struct drm_panel panel;
	struct device *dev;

	const char *label;
	unsigned int width;
	unsigned int height;
	struct videomode video_mode;
	unsigned int bus_format;
	bool data_mirror;

	struct backlight_device *backlight;
	struct regulator *supply;

	struct gpio_desc *enable_gpio;
	struct gpio_desc *reset_gpio;
	};

	static inline struct panel_lvds to_panel_lvds(struct drm_panel panel)
	{
	return container_of(panel, struct panel_lvds, panel);
	}

	static int panel_lvds_disable(struct drm_panel *panel)
	{
	struct panel_lvds *lvds = to_panel_lvds(panel);

	if (lvds->backlight) {
	lvds->backlight->props.power = FB_BLANK_POWERDOWN;
	lvds->backlight->props.state \|= BL_CORE_FBBLANK;
	backlight_update_status(lvds->backlight);
	}

	return 0;
	}

	static int panel_lvds_unprepare(struct drm_panel *panel)
	{
	struct panel_lvds *lvds = to_panel_lvds(panel);

	if (lvds->enable_gpio)
	gpiod_set_value_cansleep(lvds->enable_gpio, 0);

	if (lvds->supply)
	regulator_disable(lvds->supply);

	return 0;
	}

	static int panel_lvds_prepare(struct drm_panel *panel)
	{
	struct panel_lvds *lvds = to_panel_lvds(panel);

	if (lvds->supply) {
	int err;

	err = regulator_enable(lvds->supply);
	if (err < 0) {
	dev_err(lvds->dev, "failed to enable supply: %d\n",
	err);
	return err;
	}
	}

	if (lvds->enable_gpio)
	gpiod_set_value_cansleep(lvds->enable_gpio, 1);

	return 0;
	}

	static int panel_lvds_enable(struct drm_panel *panel)
	{
	struct panel_lvds *lvds = to_panel_lvds(panel);

	if (lvds->backlight) {
	lvds->backlight->props.state &= ~BL_CORE_FBBLANK;
	lvds->backlight->props.power = FB_BLANK_UNBLANK;
	backlight_update_status(lvds->backlight);
	}

	return 0;
	}

	static int panel_lvds_get_modes(struct drm_panel *panel)
	{
	struct panel_lvds *lvds = to_panel_lvds(panel);
	struct drm_connector *connector = lvds->panel.connector;
	struct drm_display_mode *mode;

	mode = drm_mode_create(lvds->panel.drm);
	if (!mode)
	return 0;

	drm_display_mode_from_videomode(&lvds->video_mode, mode);
	mode->type \|= DRM_MODE_TYPE_DRIVER \| DRM_MODE_TYPE_PREFERRED;
	drm_mode_probed_add(connector, mode);

	connector->display_info.width_mm = lvds->width;
	connector->display_info.height_mm = lvds->height;
	drm_display_info_set_bus_formats(&connector->display_info,
	&lvds->bus_format, 1);
	connector->display_info.bus_flags = lvds->data_mirror
	? DRM_BUS_FLAG_DATA_LSB_TO_MSB
	: DRM_BUS_FLAG_DATA_MSB_TO_LSB;

	return 1;
	}

	static const struct drm_panel_funcs panel_lvds_funcs = {
	.disable = panel_lvds_disable,
	.unprepare = panel_lvds_unprepare,
	.prepare = panel_lvds_prepare,
	.enable = panel_lvds_enable,
	.get_modes = panel_lvds_get_modes,
	};

	static int panel_lvds_parse_dt(struct panel_lvds *lvds)
	{
	struct device_node *np = lvds->dev->of_node;
	struct display_timing timing;
	const char *mapping;
	int ret;

	ret = of_get_display_timing(np, "panel-timing", &timing);
	if (ret < 0)
	return ret;

	videomode_from_timing(&timing, &lvds->video_mode);

	ret = of_property_read_u32(np, "width-mm", &lvds->width);
	if (ret < 0) {
	dev_err(lvds->dev, "%pOF: invalid or missing %s DT property\n",
	np, "width-mm");
	return -ENODEV;
	}
	ret = of_property_read_u32(np, "height-mm", &lvds->height);
	if (ret < 0) {
	dev_err(lvds->dev, "%pOF: invalid or missing %s DT property\n",
	np, "height-mm");
	return -ENODEV;
	}

	of_property_read_string(np, "label", &lvds->label);

	ret = of_property_read_string(np, "data-mapping", &mapping);
	if (ret < 0) {
	dev_err(lvds->dev, "%pOF: invalid or missing %s DT property\n",
	np, "data-mapping");
	return -ENODEV;
	}

	if (!strcmp(mapping, "jeida-18")) {
	lvds->bus_format = MEDIA_BUS_FMT_RGB666_1X7X3_SPWG;
	} else if (!strcmp(mapping, "jeida-24")) {
	lvds->bus_format = MEDIA_BUS_FMT_RGB888_1X7X4_JEIDA;
	} else if (!strcmp(mapping, "vesa-24")) {
	lvds->bus_format = MEDIA_BUS_FMT_RGB888_1X7X4_SPWG;
	} else {
	dev_err(lvds->dev, "%pOF: invalid or missing %s DT property\n",
	np, "data-mapping");
	return -EINVAL;
	}

	lvds->data_mirror = of_property_read_bool(np, "data-mirror");

	return 0;
	}

	static int panel_lvds_probe(struct platform_device *pdev)
	{
	struct panel_lvds *lvds;
	struct device_node *np;
	int ret;

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

	lvds->dev = &pdev->dev;

	ret = panel_lvds_parse_dt(lvds);
	if (ret < 0)
	return ret;

	lvds->supply = devm_regulator_get_optional(lvds->dev, "power");
	if (IS_ERR(lvds->supply)) {
	ret = PTR_ERR(lvds->supply);

	if (ret != -ENODEV) {
	if (ret != -EPROBE_DEFER)
	dev_err(lvds->dev, "failed to request regulator: %d\n",
	ret);
	return ret;
	}

	lvds->supply = NULL;
	}

	/* Get GPIOs and backlight controller. */
	lvds->enable_gpio = devm_gpiod_get_optional(lvds->dev, "enable",
	GPIOD_OUT_LOW);
	if (IS_ERR(lvds->enable_gpio)) {
	ret = PTR_ERR(lvds->enable_gpio);
	dev_err(lvds->dev, "failed to request %s GPIO: %d\n",
	"enable", ret);
	return ret;
	}

	lvds->reset_gpio = devm_gpiod_get_optional(lvds->dev, "reset",
	GPIOD_OUT_HIGH);
	if (IS_ERR(lvds->reset_gpio)) {
	ret = PTR_ERR(lvds->reset_gpio);
	dev_err(lvds->dev, "failed to request %s GPIO: %d\n",
	"reset", ret);
	return ret;
	}

	np = of_parse_phandle(lvds->dev->of_node, "backlight", 0);
	if (np) {
	lvds->backlight = of_find_backlight_by_node(np);
	of_node_put(np);

	if (!lvds->backlight)
	return -EPROBE_DEFER;
	}

	/*
	* TODO: Handle all power supplies specified in the DT node in a generic
	* way for panels that don't care about power supply ordering. LVDS
	* panels that require a specific power sequence will need a dedicated
	* driver.
	*/

	/* Register the panel. */
	drm_panel_init(&lvds->panel);
	lvds->panel.dev = lvds->dev;
	lvds->panel.funcs = &panel_lvds_funcs;

	ret = drm_panel_add(&lvds->panel);
	if (ret < 0)
	goto error;

	dev_set_drvdata(lvds->dev, lvds);
	return 0;

	error:
	put_device(&lvds->backlight->dev);
	return ret;
	}

	static int panel_lvds_remove(struct platform_device *pdev)
	{
	struct panel_lvds *lvds = dev_get_drvdata(&pdev->dev);

	drm_panel_detach(&lvds->panel);
	drm_panel_remove(&lvds->panel);

	panel_lvds_disable(&lvds->panel);

	if (lvds->backlight)
	put_device(&lvds->backlight->dev);

	return 0;
	}

	static const struct of_device_id panel_lvds_of_table[] = {
	{ .compatible = "panel-lvds", },
	{ /* Sentinel */ },
	};

	MODULE_DEVICE_TABLE(of, panel_lvds_of_table);

	static struct platform_driver panel_lvds_driver = {
	.probe = panel_lvds_probe,
	.remove = panel_lvds_remove,
	.driver = {
	.name = "panel-lvds",
	.of_match_table = panel_lvds_of_table,
	},
	};

	module_platform_driver(panel_lvds_driver);

	MODULE_AUTHOR("Laurent Pinchart <laurent.pinchart@ideasonboard.com>");
	MODULE_DESCRIPTION("LVDS Panel Driver");
	MODULE_LICENSE("GPL");