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