1 // SPDX-License-Identifier: GPL-2.0-or-later 2 /* 3 * Copyright (C) 2019 Renesas Electronics Corporation 4 * Copyright (C) 2016 Laurent Pinchart <laurent.pinchart@ideasonboard.com> 5 */ 6 7 #include <linux/gpio/consumer.h> 8 #include <linux/media-bus-format.h> 9 #include <linux/module.h> 10 #include <linux/of.h> 11 #include <linux/of_graph.h> 12 #include <linux/platform_device.h> 13 #include <linux/regulator/consumer.h> 14 15 #include <drm/drm_atomic_helper.h> 16 #include <drm/drm_bridge.h> 17 #include <drm/drm_of.h> 18 #include <drm/drm_panel.h> 19 20 struct lvds_codec { 21 struct device *dev; 22 struct drm_bridge bridge; 23 struct drm_bridge *panel_bridge; 24 struct drm_bridge_timings timings; 25 struct regulator *vcc; 26 struct gpio_desc *powerdown_gpio; 27 u32 connector_type; 28 unsigned int bus_format; 29 }; 30 31 static inline struct lvds_codec *to_lvds_codec(struct drm_bridge *bridge) 32 { 33 return container_of(bridge, struct lvds_codec, bridge); 34 } 35 36 static int lvds_codec_attach(struct drm_bridge *bridge, 37 struct drm_encoder *encoder, 38 enum drm_bridge_attach_flags flags) 39 { 40 struct lvds_codec *lvds_codec = to_lvds_codec(bridge); 41 42 return drm_bridge_attach(encoder, lvds_codec->panel_bridge, 43 bridge, flags); 44 } 45 46 static void lvds_codec_enable(struct drm_bridge *bridge, 47 struct drm_atomic_commit *commit) 48 { 49 struct lvds_codec *lvds_codec = to_lvds_codec(bridge); 50 int ret; 51 52 ret = regulator_enable(lvds_codec->vcc); 53 if (ret) { 54 dev_err(lvds_codec->dev, 55 "Failed to enable regulator \"vcc\": %d\n", ret); 56 return; 57 } 58 59 if (lvds_codec->powerdown_gpio) 60 gpiod_set_value_cansleep(lvds_codec->powerdown_gpio, 0); 61 } 62 63 static void lvds_codec_disable(struct drm_bridge *bridge, 64 struct drm_atomic_commit *commit) 65 { 66 struct lvds_codec *lvds_codec = to_lvds_codec(bridge); 67 int ret; 68 69 if (lvds_codec->powerdown_gpio) 70 gpiod_set_value_cansleep(lvds_codec->powerdown_gpio, 1); 71 72 ret = regulator_disable(lvds_codec->vcc); 73 if (ret) 74 dev_err(lvds_codec->dev, 75 "Failed to disable regulator \"vcc\": %d\n", ret); 76 } 77 78 #define MAX_INPUT_SEL_FORMATS 1 79 static u32 * 80 lvds_codec_atomic_get_input_bus_fmts(struct drm_bridge *bridge, 81 struct drm_bridge_state *bridge_state, 82 struct drm_crtc_state *crtc_state, 83 struct drm_connector_state *conn_state, 84 u32 output_fmt, 85 unsigned int *num_input_fmts) 86 { 87 struct lvds_codec *lvds_codec = to_lvds_codec(bridge); 88 u32 *input_fmts; 89 90 *num_input_fmts = 0; 91 92 input_fmts = kcalloc(MAX_INPUT_SEL_FORMATS, sizeof(*input_fmts), 93 GFP_KERNEL); 94 if (!input_fmts) 95 return NULL; 96 97 input_fmts[0] = lvds_codec->bus_format; 98 *num_input_fmts = MAX_INPUT_SEL_FORMATS; 99 100 return input_fmts; 101 } 102 103 static const struct drm_bridge_funcs funcs = { 104 .attach = lvds_codec_attach, 105 .atomic_enable = lvds_codec_enable, 106 .atomic_disable = lvds_codec_disable, 107 .atomic_duplicate_state = drm_atomic_helper_bridge_duplicate_state, 108 .atomic_destroy_state = drm_atomic_helper_bridge_destroy_state, 109 .atomic_create_state = drm_atomic_helper_bridge_create_state, 110 .atomic_get_input_bus_fmts = lvds_codec_atomic_get_input_bus_fmts, 111 }; 112 113 static int lvds_codec_probe(struct platform_device *pdev) 114 { 115 struct device *dev = &pdev->dev; 116 struct device_node *panel_node; 117 struct device_node *bus_node; 118 struct drm_panel *panel; 119 struct lvds_codec *lvds_codec; 120 u32 val; 121 int ret; 122 123 lvds_codec = devm_drm_bridge_alloc(dev, struct lvds_codec, bridge, 124 &funcs); 125 if (IS_ERR(lvds_codec)) 126 return PTR_ERR(lvds_codec); 127 128 lvds_codec->dev = &pdev->dev; 129 lvds_codec->connector_type = (uintptr_t)of_device_get_match_data(dev); 130 131 lvds_codec->vcc = devm_regulator_get(lvds_codec->dev, "power"); 132 if (IS_ERR(lvds_codec->vcc)) 133 return dev_err_probe(dev, PTR_ERR(lvds_codec->vcc), 134 "Unable to get \"vcc\" supply\n"); 135 136 lvds_codec->powerdown_gpio = devm_gpiod_get_optional(dev, "powerdown", 137 GPIOD_OUT_HIGH); 138 if (IS_ERR(lvds_codec->powerdown_gpio)) 139 return dev_err_probe(dev, PTR_ERR(lvds_codec->powerdown_gpio), 140 "powerdown GPIO failure\n"); 141 142 /* Locate the panel DT node. */ 143 panel_node = of_graph_get_remote_node(dev->of_node, 1, 0); 144 if (!panel_node) { 145 dev_dbg(dev, "panel DT node not found\n"); 146 return -ENXIO; 147 } 148 149 panel = of_drm_find_panel(panel_node); 150 of_node_put(panel_node); 151 if (IS_ERR(panel)) { 152 dev_dbg(dev, "panel not found, deferring probe\n"); 153 return PTR_ERR(panel); 154 } 155 156 lvds_codec->panel_bridge = 157 devm_drm_panel_bridge_add_typed(dev, panel, 158 lvds_codec->connector_type); 159 drm_panel_put(panel); 160 if (IS_ERR(lvds_codec->panel_bridge)) 161 return PTR_ERR(lvds_codec->panel_bridge); 162 163 /* 164 * Decoder input LVDS format is a property of the decoder chip or even 165 * its strapping. Handle data-mapping the same way lvds-panel does. In 166 * case data-mapping is not present, do nothing, since there are still 167 * legacy bindings which do not specify this property. 168 */ 169 if (lvds_codec->connector_type != DRM_MODE_CONNECTOR_LVDS) { 170 bus_node = of_graph_get_endpoint_by_regs(dev->of_node, 0, 0); 171 if (!bus_node) { 172 dev_dbg(dev, "bus DT node not found\n"); 173 return -ENXIO; 174 } 175 176 ret = drm_of_lvds_get_data_mapping(bus_node); 177 of_node_put(bus_node); 178 if (ret == -ENODEV) { 179 dev_warn(dev, "missing 'data-mapping' DT property\n"); 180 } else if (ret < 0) { 181 dev_err(dev, "invalid 'data-mapping' DT property\n"); 182 return ret; 183 } else { 184 lvds_codec->bus_format = ret; 185 } 186 } else { 187 lvds_codec->bus_format = MEDIA_BUS_FMT_RGB888_1X24; 188 } 189 190 /* 191 * Encoder might sample data on different clock edge than the display, 192 * for example OnSemi FIN3385 has a dedicated strapping pin to select 193 * the sampling edge. 194 */ 195 if (lvds_codec->connector_type == DRM_MODE_CONNECTOR_LVDS && 196 !of_property_read_u32(dev->of_node, "pclk-sample", &val)) { 197 lvds_codec->timings.input_bus_flags = val ? 198 DRM_BUS_FLAG_PIXDATA_SAMPLE_POSEDGE : 199 DRM_BUS_FLAG_PIXDATA_SAMPLE_NEGEDGE; 200 } 201 202 /* 203 * The panel_bridge bridge is attached to the panel's of_node, 204 * but we need a bridge attached to our of_node for our user 205 * to look up. 206 */ 207 lvds_codec->bridge.of_node = dev->of_node; 208 lvds_codec->bridge.timings = &lvds_codec->timings; 209 drm_bridge_add(&lvds_codec->bridge); 210 211 platform_set_drvdata(pdev, lvds_codec); 212 213 return 0; 214 } 215 216 static void lvds_codec_remove(struct platform_device *pdev) 217 { 218 struct lvds_codec *lvds_codec = platform_get_drvdata(pdev); 219 220 drm_bridge_remove(&lvds_codec->bridge); 221 } 222 223 static const struct of_device_id lvds_codec_match[] = { 224 { 225 .compatible = "lvds-decoder", 226 .data = (void *)DRM_MODE_CONNECTOR_DPI, 227 }, 228 { 229 .compatible = "lvds-encoder", 230 .data = (void *)DRM_MODE_CONNECTOR_LVDS, 231 }, 232 { 233 .compatible = "thine,thc63lvdm83d", 234 .data = (void *)DRM_MODE_CONNECTOR_LVDS, 235 }, 236 {}, 237 }; 238 MODULE_DEVICE_TABLE(of, lvds_codec_match); 239 240 static struct platform_driver lvds_codec_driver = { 241 .probe = lvds_codec_probe, 242 .remove = lvds_codec_remove, 243 .driver = { 244 .name = "lvds-codec", 245 .of_match_table = lvds_codec_match, 246 }, 247 }; 248 module_platform_driver(lvds_codec_driver); 249 250 MODULE_AUTHOR("Laurent Pinchart <laurent.pinchart@ideasonboard.com>"); 251 MODULE_DESCRIPTION("LVDS encoders and decoders"); 252 MODULE_LICENSE("GPL"); 253