1 // SPDX-License-Identifier: GPL-2.0+ 2 /* 3 * Generic LVDS panel driver 4 * 5 * Copyright (C) 2016 Laurent Pinchart 6 * Copyright (C) 2016 Renesas Electronics Corporation 7 * 8 * Contact: Laurent Pinchart (laurent.pinchart@ideasonboard.com) 9 */ 10 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> 17 18 #include <video/display_timing.h> 19 #include <video/of_display_timing.h> 20 #include <video/videomode.h> 21 22 #include <drm/drm_crtc.h> 23 #include <drm/drm_panel.h> 24 25 struct panel_lvds { 26 struct drm_panel panel; 27 struct device *dev; 28 29 const char *label; 30 unsigned int width; 31 unsigned int height; 32 struct videomode video_mode; 33 unsigned int bus_format; 34 bool data_mirror; 35 36 struct regulator *supply; 37 38 struct gpio_desc *enable_gpio; 39 struct gpio_desc *reset_gpio; 40 }; 41 42 static inline struct panel_lvds *to_panel_lvds(struct drm_panel *panel) 43 { 44 return container_of(panel, struct panel_lvds, panel); 45 } 46 47 static int panel_lvds_unprepare(struct drm_panel *panel) 48 { 49 struct panel_lvds *lvds = to_panel_lvds(panel); 50 51 if (lvds->enable_gpio) 52 gpiod_set_value_cansleep(lvds->enable_gpio, 0); 53 54 if (lvds->supply) 55 regulator_disable(lvds->supply); 56 57 return 0; 58 } 59 60 static int panel_lvds_prepare(struct drm_panel *panel) 61 { 62 struct panel_lvds *lvds = to_panel_lvds(panel); 63 64 if (lvds->supply) { 65 int err; 66 67 err = regulator_enable(lvds->supply); 68 if (err < 0) { 69 dev_err(lvds->dev, "failed to enable supply: %d\n", 70 err); 71 return err; 72 } 73 } 74 75 if (lvds->enable_gpio) 76 gpiod_set_value_cansleep(lvds->enable_gpio, 1); 77 78 return 0; 79 } 80 81 static int panel_lvds_get_modes(struct drm_panel *panel, 82 struct drm_connector *connector) 83 { 84 struct panel_lvds *lvds = to_panel_lvds(panel); 85 struct drm_display_mode *mode; 86 87 mode = drm_mode_create(connector->dev); 88 if (!mode) 89 return 0; 90 91 drm_display_mode_from_videomode(&lvds->video_mode, mode); 92 mode->type |= DRM_MODE_TYPE_DRIVER | DRM_MODE_TYPE_PREFERRED; 93 drm_mode_probed_add(connector, mode); 94 95 connector->display_info.width_mm = lvds->width; 96 connector->display_info.height_mm = lvds->height; 97 drm_display_info_set_bus_formats(&connector->display_info, 98 &lvds->bus_format, 1); 99 connector->display_info.bus_flags = lvds->data_mirror 100 ? DRM_BUS_FLAG_DATA_LSB_TO_MSB 101 : DRM_BUS_FLAG_DATA_MSB_TO_LSB; 102 103 return 1; 104 } 105 106 static const struct drm_panel_funcs panel_lvds_funcs = { 107 .unprepare = panel_lvds_unprepare, 108 .prepare = panel_lvds_prepare, 109 .get_modes = panel_lvds_get_modes, 110 }; 111 112 static int panel_lvds_parse_dt(struct panel_lvds *lvds) 113 { 114 struct device_node *np = lvds->dev->of_node; 115 struct display_timing timing; 116 const char *mapping; 117 int ret; 118 119 ret = of_get_display_timing(np, "panel-timing", &timing); 120 if (ret < 0) { 121 dev_err(lvds->dev, "%pOF: problems parsing panel-timing (%d)\n", 122 np, ret); 123 return ret; 124 } 125 126 videomode_from_timing(&timing, &lvds->video_mode); 127 128 ret = of_property_read_u32(np, "width-mm", &lvds->width); 129 if (ret < 0) { 130 dev_err(lvds->dev, "%pOF: invalid or missing %s DT property\n", 131 np, "width-mm"); 132 return -ENODEV; 133 } 134 ret = of_property_read_u32(np, "height-mm", &lvds->height); 135 if (ret < 0) { 136 dev_err(lvds->dev, "%pOF: invalid or missing %s DT property\n", 137 np, "height-mm"); 138 return -ENODEV; 139 } 140 141 of_property_read_string(np, "label", &lvds->label); 142 143 ret = of_property_read_string(np, "data-mapping", &mapping); 144 if (ret < 0) { 145 dev_err(lvds->dev, "%pOF: invalid or missing %s DT property\n", 146 np, "data-mapping"); 147 return -ENODEV; 148 } 149 150 if (!strcmp(mapping, "jeida-18")) { 151 lvds->bus_format = MEDIA_BUS_FMT_RGB666_1X7X3_SPWG; 152 } else if (!strcmp(mapping, "jeida-24")) { 153 lvds->bus_format = MEDIA_BUS_FMT_RGB888_1X7X4_JEIDA; 154 } else if (!strcmp(mapping, "vesa-24")) { 155 lvds->bus_format = MEDIA_BUS_FMT_RGB888_1X7X4_SPWG; 156 } else { 157 dev_err(lvds->dev, "%pOF: invalid or missing %s DT property\n", 158 np, "data-mapping"); 159 return -EINVAL; 160 } 161 162 lvds->data_mirror = of_property_read_bool(np, "data-mirror"); 163 164 return 0; 165 } 166 167 static int panel_lvds_probe(struct platform_device *pdev) 168 { 169 struct panel_lvds *lvds; 170 int ret; 171 172 lvds = devm_kzalloc(&pdev->dev, sizeof(*lvds), GFP_KERNEL); 173 if (!lvds) 174 return -ENOMEM; 175 176 lvds->dev = &pdev->dev; 177 178 ret = panel_lvds_parse_dt(lvds); 179 if (ret < 0) 180 return ret; 181 182 lvds->supply = devm_regulator_get_optional(lvds->dev, "power"); 183 if (IS_ERR(lvds->supply)) { 184 ret = PTR_ERR(lvds->supply); 185 186 if (ret != -ENODEV) { 187 if (ret != -EPROBE_DEFER) 188 dev_err(lvds->dev, "failed to request regulator: %d\n", 189 ret); 190 return ret; 191 } 192 193 lvds->supply = NULL; 194 } 195 196 /* Get GPIOs and backlight controller. */ 197 lvds->enable_gpio = devm_gpiod_get_optional(lvds->dev, "enable", 198 GPIOD_OUT_LOW); 199 if (IS_ERR(lvds->enable_gpio)) { 200 ret = PTR_ERR(lvds->enable_gpio); 201 dev_err(lvds->dev, "failed to request %s GPIO: %d\n", 202 "enable", ret); 203 return ret; 204 } 205 206 lvds->reset_gpio = devm_gpiod_get_optional(lvds->dev, "reset", 207 GPIOD_OUT_HIGH); 208 if (IS_ERR(lvds->reset_gpio)) { 209 ret = PTR_ERR(lvds->reset_gpio); 210 dev_err(lvds->dev, "failed to request %s GPIO: %d\n", 211 "reset", ret); 212 return ret; 213 } 214 215 /* 216 * TODO: Handle all power supplies specified in the DT node in a generic 217 * way for panels that don't care about power supply ordering. LVDS 218 * panels that require a specific power sequence will need a dedicated 219 * driver. 220 */ 221 222 /* Register the panel. */ 223 drm_panel_init(&lvds->panel, lvds->dev, &panel_lvds_funcs, 224 DRM_MODE_CONNECTOR_LVDS); 225 226 ret = drm_panel_of_backlight(&lvds->panel); 227 if (ret) 228 return ret; 229 230 ret = drm_panel_add(&lvds->panel); 231 if (ret < 0) 232 return ret; 233 234 dev_set_drvdata(lvds->dev, lvds); 235 return 0; 236 } 237 238 static int panel_lvds_remove(struct platform_device *pdev) 239 { 240 struct panel_lvds *lvds = dev_get_drvdata(&pdev->dev); 241 242 drm_panel_remove(&lvds->panel); 243 244 drm_panel_disable(&lvds->panel); 245 246 return 0; 247 } 248 249 static const struct of_device_id panel_lvds_of_table[] = { 250 { .compatible = "panel-lvds", }, 251 { /* Sentinel */ }, 252 }; 253 254 MODULE_DEVICE_TABLE(of, panel_lvds_of_table); 255 256 static struct platform_driver panel_lvds_driver = { 257 .probe = panel_lvds_probe, 258 .remove = panel_lvds_remove, 259 .driver = { 260 .name = "panel-lvds", 261 .of_match_table = panel_lvds_of_table, 262 }, 263 }; 264 265 module_platform_driver(panel_lvds_driver); 266 267 MODULE_AUTHOR("Laurent Pinchart <laurent.pinchart@ideasonboard.com>"); 268 MODULE_DESCRIPTION("LVDS Panel Driver"); 269 MODULE_LICENSE("GPL"); 270