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.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 struct drm_display_mode dmode; 32 u32 bus_flags; 33 unsigned int bus_format; 34 35 struct regulator *supply; 36 37 struct gpio_desc *enable_gpio; 38 struct gpio_desc *reset_gpio; 39 40 enum drm_panel_orientation orientation; 41 }; 42 43 static inline struct panel_lvds *to_panel_lvds(struct drm_panel *panel) 44 { 45 return container_of(panel, struct panel_lvds, panel); 46 } 47 48 static int panel_lvds_unprepare(struct drm_panel *panel) 49 { 50 struct panel_lvds *lvds = to_panel_lvds(panel); 51 52 if (lvds->enable_gpio) 53 gpiod_set_value_cansleep(lvds->enable_gpio, 0); 54 55 if (lvds->supply) 56 regulator_disable(lvds->supply); 57 58 return 0; 59 } 60 61 static int panel_lvds_prepare(struct drm_panel *panel) 62 { 63 struct panel_lvds *lvds = to_panel_lvds(panel); 64 65 if (lvds->supply) { 66 int err; 67 68 err = regulator_enable(lvds->supply); 69 if (err < 0) { 70 dev_err(lvds->dev, "failed to enable supply: %d\n", 71 err); 72 return err; 73 } 74 } 75 76 if (lvds->enable_gpio) 77 gpiod_set_value_cansleep(lvds->enable_gpio, 1); 78 79 return 0; 80 } 81 82 static int panel_lvds_get_modes(struct drm_panel *panel, 83 struct drm_connector *connector) 84 { 85 struct panel_lvds *lvds = to_panel_lvds(panel); 86 struct drm_display_mode *mode; 87 88 mode = drm_mode_duplicate(connector->dev, &lvds->dmode); 89 if (!mode) 90 return 0; 91 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->dmode.width_mm; 96 connector->display_info.height_mm = lvds->dmode.height_mm; 97 drm_display_info_set_bus_formats(&connector->display_info, 98 &lvds->bus_format, 1); 99 connector->display_info.bus_flags = lvds->bus_flags; 100 101 /* 102 * TODO: Remove once all drm drivers call 103 * drm_connector_set_orientation_from_panel() 104 */ 105 drm_connector_set_panel_orientation(connector, lvds->orientation); 106 107 return 1; 108 } 109 110 static enum drm_panel_orientation panel_lvds_get_orientation(struct drm_panel *panel) 111 { 112 struct panel_lvds *lvds = to_panel_lvds(panel); 113 114 return lvds->orientation; 115 } 116 117 static const struct drm_panel_funcs panel_lvds_funcs = { 118 .unprepare = panel_lvds_unprepare, 119 .prepare = panel_lvds_prepare, 120 .get_modes = panel_lvds_get_modes, 121 .get_orientation = panel_lvds_get_orientation, 122 }; 123 124 static int panel_lvds_parse_dt(struct panel_lvds *lvds) 125 { 126 struct device_node *np = lvds->dev->of_node; 127 int ret; 128 129 ret = of_drm_get_panel_orientation(np, &lvds->orientation); 130 if (ret < 0) { 131 dev_err(lvds->dev, "%pOF: failed to get orientation %d\n", np, ret); 132 return ret; 133 } 134 135 ret = of_get_drm_panel_display_mode(np, &lvds->dmode, &lvds->bus_flags); 136 if (ret < 0) { 137 dev_err(lvds->dev, "%pOF: problems parsing panel-timing (%d)\n", 138 np, ret); 139 return ret; 140 } 141 142 of_property_read_string(np, "label", &lvds->label); 143 144 ret = drm_of_lvds_get_data_mapping(np); 145 if (ret < 0) { 146 dev_err(lvds->dev, "%pOF: invalid or missing %s DT property\n", 147 np, "data-mapping"); 148 return ret; 149 } 150 151 lvds->bus_format = ret; 152 153 lvds->bus_flags |= of_property_read_bool(np, "data-mirror") ? 154 DRM_BUS_FLAG_DATA_LSB_TO_MSB : 155 DRM_BUS_FLAG_DATA_MSB_TO_LSB; 156 157 return 0; 158 } 159 160 static int panel_lvds_probe(struct platform_device *pdev) 161 { 162 struct panel_lvds *lvds; 163 int ret; 164 165 lvds = devm_drm_panel_alloc(&pdev->dev, struct panel_lvds, panel, 166 &panel_lvds_funcs, 167 DRM_MODE_CONNECTOR_LVDS); 168 if (IS_ERR(lvds)) 169 return PTR_ERR(lvds); 170 171 lvds->dev = &pdev->dev; 172 173 ret = panel_lvds_parse_dt(lvds); 174 if (ret < 0) 175 return ret; 176 177 lvds->supply = devm_regulator_get_optional(lvds->dev, "power"); 178 if (IS_ERR(lvds->supply)) { 179 ret = PTR_ERR(lvds->supply); 180 181 if (ret != -ENODEV) { 182 if (ret != -EPROBE_DEFER) 183 dev_err(lvds->dev, "failed to request regulator: %d\n", 184 ret); 185 return ret; 186 } 187 188 lvds->supply = NULL; 189 } 190 191 /* Get GPIOs and backlight controller. */ 192 lvds->enable_gpio = devm_gpiod_get_optional(lvds->dev, "enable", 193 GPIOD_OUT_LOW); 194 if (IS_ERR(lvds->enable_gpio)) { 195 ret = PTR_ERR(lvds->enable_gpio); 196 dev_err(lvds->dev, "failed to request %s GPIO: %d\n", 197 "enable", ret); 198 return ret; 199 } 200 201 lvds->reset_gpio = devm_gpiod_get_optional(lvds->dev, "reset", 202 GPIOD_OUT_HIGH); 203 if (IS_ERR(lvds->reset_gpio)) { 204 ret = PTR_ERR(lvds->reset_gpio); 205 dev_err(lvds->dev, "failed to request %s GPIO: %d\n", 206 "reset", ret); 207 return ret; 208 } 209 210 /* 211 * TODO: Handle all power supplies specified in the DT node in a generic 212 * way for panels that don't care about power supply ordering. LVDS 213 * panels that require a specific power sequence will need a dedicated 214 * driver. 215 */ 216 217 ret = drm_panel_of_backlight(&lvds->panel); 218 if (ret) 219 return ret; 220 221 drm_panel_add(&lvds->panel); 222 223 dev_set_drvdata(lvds->dev, lvds); 224 return 0; 225 } 226 227 static void panel_lvds_remove(struct platform_device *pdev) 228 { 229 struct panel_lvds *lvds = platform_get_drvdata(pdev); 230 231 drm_panel_remove(&lvds->panel); 232 233 drm_panel_disable(&lvds->panel); 234 } 235 236 static const struct of_device_id panel_lvds_of_table[] = { 237 { .compatible = "panel-lvds", }, 238 { /* Sentinel */ }, 239 }; 240 241 MODULE_DEVICE_TABLE(of, panel_lvds_of_table); 242 243 static struct platform_driver panel_lvds_driver = { 244 .probe = panel_lvds_probe, 245 .remove = panel_lvds_remove, 246 .driver = { 247 .name = "panel-lvds", 248 .of_match_table = panel_lvds_of_table, 249 }, 250 }; 251 252 module_platform_driver(panel_lvds_driver); 253 254 MODULE_AUTHOR("Laurent Pinchart <laurent.pinchart@ideasonboard.com>"); 255 MODULE_DESCRIPTION("LVDS Panel Driver"); 256 MODULE_LICENSE("GPL"); 257