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 enum drm_panel_orientation orientation; 42 }; 43 44 static inline struct panel_lvds *to_panel_lvds(struct drm_panel *panel) 45 { 46 return container_of(panel, struct panel_lvds, panel); 47 } 48 49 static int panel_lvds_unprepare(struct drm_panel *panel) 50 { 51 struct panel_lvds *lvds = to_panel_lvds(panel); 52 53 if (lvds->enable_gpio) 54 gpiod_set_value_cansleep(lvds->enable_gpio, 0); 55 56 if (lvds->supply) 57 regulator_disable(lvds->supply); 58 59 return 0; 60 } 61 62 static int panel_lvds_prepare(struct drm_panel *panel) 63 { 64 struct panel_lvds *lvds = to_panel_lvds(panel); 65 66 if (lvds->supply) { 67 int err; 68 69 err = regulator_enable(lvds->supply); 70 if (err < 0) { 71 dev_err(lvds->dev, "failed to enable supply: %d\n", 72 err); 73 return err; 74 } 75 } 76 77 if (lvds->enable_gpio) 78 gpiod_set_value_cansleep(lvds->enable_gpio, 1); 79 80 return 0; 81 } 82 83 static int panel_lvds_get_modes(struct drm_panel *panel, 84 struct drm_connector *connector) 85 { 86 struct panel_lvds *lvds = to_panel_lvds(panel); 87 struct drm_display_mode *mode; 88 89 mode = drm_mode_create(connector->dev); 90 if (!mode) 91 return 0; 92 93 drm_display_mode_from_videomode(&lvds->video_mode, mode); 94 mode->type |= DRM_MODE_TYPE_DRIVER | DRM_MODE_TYPE_PREFERRED; 95 drm_mode_probed_add(connector, mode); 96 97 connector->display_info.width_mm = lvds->width; 98 connector->display_info.height_mm = lvds->height; 99 drm_display_info_set_bus_formats(&connector->display_info, 100 &lvds->bus_format, 1); 101 connector->display_info.bus_flags = lvds->data_mirror 102 ? DRM_BUS_FLAG_DATA_LSB_TO_MSB 103 : DRM_BUS_FLAG_DATA_MSB_TO_LSB; 104 drm_connector_set_panel_orientation(connector, lvds->orientation); 105 106 return 1; 107 } 108 109 static const struct drm_panel_funcs panel_lvds_funcs = { 110 .unprepare = panel_lvds_unprepare, 111 .prepare = panel_lvds_prepare, 112 .get_modes = panel_lvds_get_modes, 113 }; 114 115 static int panel_lvds_parse_dt(struct panel_lvds *lvds) 116 { 117 struct device_node *np = lvds->dev->of_node; 118 struct display_timing timing; 119 const char *mapping; 120 int ret; 121 122 ret = of_drm_get_panel_orientation(np, &lvds->orientation); 123 if (ret < 0) { 124 dev_err(lvds->dev, "%pOF: failed to get orientation %d\n", np, ret); 125 return ret; 126 } 127 128 ret = of_get_display_timing(np, "panel-timing", &timing); 129 if (ret < 0) { 130 dev_err(lvds->dev, "%pOF: problems parsing panel-timing (%d)\n", 131 np, ret); 132 return ret; 133 } 134 135 videomode_from_timing(&timing, &lvds->video_mode); 136 137 ret = of_property_read_u32(np, "width-mm", &lvds->width); 138 if (ret < 0) { 139 dev_err(lvds->dev, "%pOF: invalid or missing %s DT property\n", 140 np, "width-mm"); 141 return -ENODEV; 142 } 143 ret = of_property_read_u32(np, "height-mm", &lvds->height); 144 if (ret < 0) { 145 dev_err(lvds->dev, "%pOF: invalid or missing %s DT property\n", 146 np, "height-mm"); 147 return -ENODEV; 148 } 149 150 of_property_read_string(np, "label", &lvds->label); 151 152 ret = of_property_read_string(np, "data-mapping", &mapping); 153 if (ret < 0) { 154 dev_err(lvds->dev, "%pOF: invalid or missing %s DT property\n", 155 np, "data-mapping"); 156 return -ENODEV; 157 } 158 159 if (!strcmp(mapping, "jeida-18")) { 160 lvds->bus_format = MEDIA_BUS_FMT_RGB666_1X7X3_SPWG; 161 } else if (!strcmp(mapping, "jeida-24")) { 162 lvds->bus_format = MEDIA_BUS_FMT_RGB888_1X7X4_JEIDA; 163 } else if (!strcmp(mapping, "vesa-24")) { 164 lvds->bus_format = MEDIA_BUS_FMT_RGB888_1X7X4_SPWG; 165 } else { 166 dev_err(lvds->dev, "%pOF: invalid or missing %s DT property\n", 167 np, "data-mapping"); 168 return -EINVAL; 169 } 170 171 lvds->data_mirror = of_property_read_bool(np, "data-mirror"); 172 173 return 0; 174 } 175 176 static int panel_lvds_probe(struct platform_device *pdev) 177 { 178 struct panel_lvds *lvds; 179 int ret; 180 181 lvds = devm_kzalloc(&pdev->dev, sizeof(*lvds), GFP_KERNEL); 182 if (!lvds) 183 return -ENOMEM; 184 185 lvds->dev = &pdev->dev; 186 187 ret = panel_lvds_parse_dt(lvds); 188 if (ret < 0) 189 return ret; 190 191 lvds->supply = devm_regulator_get_optional(lvds->dev, "power"); 192 if (IS_ERR(lvds->supply)) { 193 ret = PTR_ERR(lvds->supply); 194 195 if (ret != -ENODEV) { 196 if (ret != -EPROBE_DEFER) 197 dev_err(lvds->dev, "failed to request regulator: %d\n", 198 ret); 199 return ret; 200 } 201 202 lvds->supply = NULL; 203 } 204 205 /* Get GPIOs and backlight controller. */ 206 lvds->enable_gpio = devm_gpiod_get_optional(lvds->dev, "enable", 207 GPIOD_OUT_LOW); 208 if (IS_ERR(lvds->enable_gpio)) { 209 ret = PTR_ERR(lvds->enable_gpio); 210 dev_err(lvds->dev, "failed to request %s GPIO: %d\n", 211 "enable", ret); 212 return ret; 213 } 214 215 lvds->reset_gpio = devm_gpiod_get_optional(lvds->dev, "reset", 216 GPIOD_OUT_HIGH); 217 if (IS_ERR(lvds->reset_gpio)) { 218 ret = PTR_ERR(lvds->reset_gpio); 219 dev_err(lvds->dev, "failed to request %s GPIO: %d\n", 220 "reset", ret); 221 return ret; 222 } 223 224 /* 225 * TODO: Handle all power supplies specified in the DT node in a generic 226 * way for panels that don't care about power supply ordering. LVDS 227 * panels that require a specific power sequence will need a dedicated 228 * driver. 229 */ 230 231 /* Register the panel. */ 232 drm_panel_init(&lvds->panel, lvds->dev, &panel_lvds_funcs, 233 DRM_MODE_CONNECTOR_LVDS); 234 235 ret = drm_panel_of_backlight(&lvds->panel); 236 if (ret) 237 return ret; 238 239 drm_panel_add(&lvds->panel); 240 241 dev_set_drvdata(lvds->dev, lvds); 242 return 0; 243 } 244 245 static int panel_lvds_remove(struct platform_device *pdev) 246 { 247 struct panel_lvds *lvds = platform_get_drvdata(pdev); 248 249 drm_panel_remove(&lvds->panel); 250 251 drm_panel_disable(&lvds->panel); 252 253 return 0; 254 } 255 256 static const struct of_device_id panel_lvds_of_table[] = { 257 { .compatible = "panel-lvds", }, 258 { /* Sentinel */ }, 259 }; 260 261 MODULE_DEVICE_TABLE(of, panel_lvds_of_table); 262 263 static struct platform_driver panel_lvds_driver = { 264 .probe = panel_lvds_probe, 265 .remove = panel_lvds_remove, 266 .driver = { 267 .name = "panel-lvds", 268 .of_match_table = panel_lvds_of_table, 269 }, 270 }; 271 272 module_platform_driver(panel_lvds_driver); 273 274 MODULE_AUTHOR("Laurent Pinchart <laurent.pinchart@ideasonboard.com>"); 275 MODULE_DESCRIPTION("LVDS Panel Driver"); 276 MODULE_LICENSE("GPL"); 277