1 // SPDX-License-Identifier: GPL-2.0+
3 * Generic LVDS panel driver
5 * Copyright (C) 2016 Laurent Pinchart
6 * Copyright (C) 2016 Renesas Electronics Corporation
8 * Contact: Laurent Pinchart (laurent.pinchart@ideasonboard.com)
11 #include <linux/gpio/consumer.h>
12 #include <linux/module.h>
13 #include <linux/of_platform.h>
14 #include <linux/platform_device.h>
15 #include <linux/regulator/consumer.h>
16 #include <linux/slab.h>
18 #include <video/display_timing.h>
19 #include <video/of_display_timing.h>
20 #include <video/videomode.h>
22 #include <drm/drm_crtc.h>
23 #include <drm/drm_of.h>
24 #include <drm/drm_panel.h>
27 struct drm_panel panel;
33 struct drm_display_mode dmode;
35 unsigned int bus_format;
37 struct regulator *supply;
39 struct gpio_desc *enable_gpio;
40 struct gpio_desc *reset_gpio;
42 enum drm_panel_orientation orientation;
45 static inline struct panel_lvds *to_panel_lvds(struct drm_panel *panel)
47 return container_of(panel, struct panel_lvds, panel);
50 static int panel_lvds_unprepare(struct drm_panel *panel)
52 struct panel_lvds *lvds = to_panel_lvds(panel);
54 if (lvds->enable_gpio)
55 gpiod_set_value_cansleep(lvds->enable_gpio, 0);
58 regulator_disable(lvds->supply);
63 static int panel_lvds_prepare(struct drm_panel *panel)
65 struct panel_lvds *lvds = to_panel_lvds(panel);
70 err = regulator_enable(lvds->supply);
72 dev_err(lvds->dev, "failed to enable supply: %d\n",
78 if (lvds->enable_gpio)
79 gpiod_set_value_cansleep(lvds->enable_gpio, 1);
84 static int panel_lvds_get_modes(struct drm_panel *panel,
85 struct drm_connector *connector)
87 struct panel_lvds *lvds = to_panel_lvds(panel);
88 struct drm_display_mode *mode;
90 mode = drm_mode_duplicate(connector->dev, &lvds->dmode);
94 mode->type |= DRM_MODE_TYPE_DRIVER | DRM_MODE_TYPE_PREFERRED;
95 drm_mode_probed_add(connector, mode);
97 connector->display_info.width_mm = lvds->dmode.width_mm;
98 connector->display_info.height_mm = lvds->dmode.height_mm;
99 drm_display_info_set_bus_formats(&connector->display_info,
100 &lvds->bus_format, 1);
101 connector->display_info.bus_flags = lvds->bus_flags;
102 drm_connector_set_panel_orientation(connector, lvds->orientation);
107 static const struct drm_panel_funcs panel_lvds_funcs = {
108 .unprepare = panel_lvds_unprepare,
109 .prepare = panel_lvds_prepare,
110 .get_modes = panel_lvds_get_modes,
113 static int panel_lvds_parse_dt(struct panel_lvds *lvds)
115 struct device_node *np = lvds->dev->of_node;
118 ret = of_drm_get_panel_orientation(np, &lvds->orientation);
120 dev_err(lvds->dev, "%pOF: failed to get orientation %d\n", np, ret);
124 ret = of_get_drm_panel_display_mode(np, &lvds->dmode, &lvds->bus_flags);
126 dev_err(lvds->dev, "%pOF: problems parsing panel-timing (%d)\n",
131 of_property_read_string(np, "label", &lvds->label);
133 ret = drm_of_lvds_get_data_mapping(np);
135 dev_err(lvds->dev, "%pOF: invalid or missing %s DT property\n",
140 lvds->bus_format = ret;
142 lvds->bus_flags |= of_property_read_bool(np, "data-mirror") ?
143 DRM_BUS_FLAG_DATA_LSB_TO_MSB :
144 DRM_BUS_FLAG_DATA_MSB_TO_LSB;
149 static int panel_lvds_probe(struct platform_device *pdev)
151 struct panel_lvds *lvds;
154 lvds = devm_kzalloc(&pdev->dev, sizeof(*lvds), GFP_KERNEL);
158 lvds->dev = &pdev->dev;
160 ret = panel_lvds_parse_dt(lvds);
164 lvds->supply = devm_regulator_get_optional(lvds->dev, "power");
165 if (IS_ERR(lvds->supply)) {
166 ret = PTR_ERR(lvds->supply);
168 if (ret != -ENODEV) {
169 if (ret != -EPROBE_DEFER)
170 dev_err(lvds->dev, "failed to request regulator: %d\n",
178 /* Get GPIOs and backlight controller. */
179 lvds->enable_gpio = devm_gpiod_get_optional(lvds->dev, "enable",
181 if (IS_ERR(lvds->enable_gpio)) {
182 ret = PTR_ERR(lvds->enable_gpio);
183 dev_err(lvds->dev, "failed to request %s GPIO: %d\n",
188 lvds->reset_gpio = devm_gpiod_get_optional(lvds->dev, "reset",
190 if (IS_ERR(lvds->reset_gpio)) {
191 ret = PTR_ERR(lvds->reset_gpio);
192 dev_err(lvds->dev, "failed to request %s GPIO: %d\n",
198 * TODO: Handle all power supplies specified in the DT node in a generic
199 * way for panels that don't care about power supply ordering. LVDS
200 * panels that require a specific power sequence will need a dedicated
204 /* Register the panel. */
205 drm_panel_init(&lvds->panel, lvds->dev, &panel_lvds_funcs,
206 DRM_MODE_CONNECTOR_LVDS);
208 ret = drm_panel_of_backlight(&lvds->panel);
212 drm_panel_add(&lvds->panel);
214 dev_set_drvdata(lvds->dev, lvds);
218 static int panel_lvds_remove(struct platform_device *pdev)
220 struct panel_lvds *lvds = platform_get_drvdata(pdev);
222 drm_panel_remove(&lvds->panel);
224 drm_panel_disable(&lvds->panel);
229 static const struct of_device_id panel_lvds_of_table[] = {
230 { .compatible = "panel-lvds", },
234 MODULE_DEVICE_TABLE(of, panel_lvds_of_table);
236 static struct platform_driver panel_lvds_driver = {
237 .probe = panel_lvds_probe,
238 .remove = panel_lvds_remove,
240 .name = "panel-lvds",
241 .of_match_table = panel_lvds_of_table,
245 module_platform_driver(panel_lvds_driver);
247 MODULE_AUTHOR("Laurent Pinchart <laurent.pinchart@ideasonboard.com>");
248 MODULE_DESCRIPTION("LVDS Panel Driver");
249 MODULE_LICENSE("GPL");