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/module.h> 9 #include <linux/of.h> 10 #include <linux/of_graph.h> 11 #include <linux/platform_device.h> 12 #include <linux/regulator/consumer.h> 13 14 #include <drm/drm_atomic_helper.h> 15 #include <drm/drm_bridge.h> 16 #include <drm/drm_of.h> 17 #include <drm/drm_panel.h> 18 19 struct lvds_codec { 20 struct device *dev; 21 struct drm_bridge bridge; 22 struct drm_bridge *panel_bridge; 23 struct drm_bridge_timings timings; 24 struct regulator *vcc; 25 struct gpio_desc *powerdown_gpio; 26 u32 connector_type; 27 unsigned int bus_format; 28 }; 29 30 static inline struct lvds_codec *to_lvds_codec(struct drm_bridge *bridge) 31 { 32 return container_of(bridge, struct lvds_codec, bridge); 33 } 34 35 static int lvds_codec_attach(struct drm_bridge *bridge, 36 enum drm_bridge_attach_flags flags) 37 { 38 struct lvds_codec *lvds_codec = to_lvds_codec(bridge); 39 40 return drm_bridge_attach(bridge->encoder, lvds_codec->panel_bridge, 41 bridge, flags); 42 } 43 44 static void lvds_codec_enable(struct drm_bridge *bridge) 45 { 46 struct lvds_codec *lvds_codec = to_lvds_codec(bridge); 47 int ret; 48 49 ret = regulator_enable(lvds_codec->vcc); 50 if (ret) { 51 dev_err(lvds_codec->dev, 52 "Failed to enable regulator \"vcc\": %d\n", ret); 53 return; 54 } 55 56 if (lvds_codec->powerdown_gpio) 57 gpiod_set_value_cansleep(lvds_codec->powerdown_gpio, 0); 58 } 59 60 static void lvds_codec_disable(struct drm_bridge *bridge) 61 { 62 struct lvds_codec *lvds_codec = to_lvds_codec(bridge); 63 int ret; 64 65 if (lvds_codec->powerdown_gpio) 66 gpiod_set_value_cansleep(lvds_codec->powerdown_gpio, 1); 67 68 ret = regulator_disable(lvds_codec->vcc); 69 if (ret) 70 dev_err(lvds_codec->dev, 71 "Failed to disable regulator \"vcc\": %d\n", ret); 72 } 73 74 static const struct drm_bridge_funcs funcs = { 75 .attach = lvds_codec_attach, 76 .enable = lvds_codec_enable, 77 .disable = lvds_codec_disable, 78 }; 79 80 #define MAX_INPUT_SEL_FORMATS 1 81 static u32 * 82 lvds_codec_atomic_get_input_bus_fmts(struct drm_bridge *bridge, 83 struct drm_bridge_state *bridge_state, 84 struct drm_crtc_state *crtc_state, 85 struct drm_connector_state *conn_state, 86 u32 output_fmt, 87 unsigned int *num_input_fmts) 88 { 89 struct lvds_codec *lvds_codec = to_lvds_codec(bridge); 90 u32 *input_fmts; 91 92 *num_input_fmts = 0; 93 94 input_fmts = kcalloc(MAX_INPUT_SEL_FORMATS, sizeof(*input_fmts), 95 GFP_KERNEL); 96 if (!input_fmts) 97 return NULL; 98 99 input_fmts[0] = lvds_codec->bus_format; 100 *num_input_fmts = MAX_INPUT_SEL_FORMATS; 101 102 return input_fmts; 103 } 104 105 static const struct drm_bridge_funcs funcs_decoder = { 106 .attach = lvds_codec_attach, 107 .enable = lvds_codec_enable, 108 .disable = lvds_codec_disable, 109 .atomic_duplicate_state = drm_atomic_helper_bridge_duplicate_state, 110 .atomic_destroy_state = drm_atomic_helper_bridge_destroy_state, 111 .atomic_reset = drm_atomic_helper_bridge_reset, 112 .atomic_get_input_bus_fmts = lvds_codec_atomic_get_input_bus_fmts, 113 }; 114 115 static int lvds_codec_probe(struct platform_device *pdev) 116 { 117 struct device *dev = &pdev->dev; 118 struct device_node *panel_node; 119 struct device_node *bus_node; 120 struct drm_panel *panel; 121 struct lvds_codec *lvds_codec; 122 u32 val; 123 int ret; 124 125 lvds_codec = devm_kzalloc(dev, sizeof(*lvds_codec), GFP_KERNEL); 126 if (!lvds_codec) 127 return -ENOMEM; 128 129 lvds_codec->dev = &pdev->dev; 130 lvds_codec->connector_type = (uintptr_t)of_device_get_match_data(dev); 131 132 lvds_codec->vcc = devm_regulator_get(lvds_codec->dev, "power"); 133 if (IS_ERR(lvds_codec->vcc)) 134 return dev_err_probe(dev, PTR_ERR(lvds_codec->vcc), 135 "Unable to get \"vcc\" supply\n"); 136 137 lvds_codec->powerdown_gpio = devm_gpiod_get_optional(dev, "powerdown", 138 GPIOD_OUT_HIGH); 139 if (IS_ERR(lvds_codec->powerdown_gpio)) 140 return dev_err_probe(dev, PTR_ERR(lvds_codec->powerdown_gpio), 141 "powerdown GPIO failure\n"); 142 143 /* Locate the panel DT node. */ 144 panel_node = of_graph_get_remote_node(dev->of_node, 1, 0); 145 if (!panel_node) { 146 dev_dbg(dev, "panel DT node not found\n"); 147 return -ENXIO; 148 } 149 150 panel = of_drm_find_panel(panel_node); 151 of_node_put(panel_node); 152 if (IS_ERR(panel)) { 153 dev_dbg(dev, "panel not found, deferring probe\n"); 154 return PTR_ERR(panel); 155 } 156 157 lvds_codec->panel_bridge = 158 devm_drm_panel_bridge_add_typed(dev, panel, 159 lvds_codec->connector_type); 160 if (IS_ERR(lvds_codec->panel_bridge)) 161 return PTR_ERR(lvds_codec->panel_bridge); 162 163 lvds_codec->bridge.funcs = &funcs; 164 165 /* 166 * Decoder input LVDS format is a property of the decoder chip or even 167 * its strapping. Handle data-mapping the same way lvds-panel does. In 168 * case data-mapping is not present, do nothing, since there are still 169 * legacy bindings which do not specify this property. 170 */ 171 if (lvds_codec->connector_type != DRM_MODE_CONNECTOR_LVDS) { 172 bus_node = of_graph_get_endpoint_by_regs(dev->of_node, 0, 0); 173 if (!bus_node) { 174 dev_dbg(dev, "bus DT node not found\n"); 175 return -ENXIO; 176 } 177 178 ret = drm_of_lvds_get_data_mapping(bus_node); 179 of_node_put(bus_node); 180 if (ret == -ENODEV) { 181 dev_warn(dev, "missing 'data-mapping' DT property\n"); 182 } else if (ret < 0) { 183 dev_err(dev, "invalid 'data-mapping' DT property\n"); 184 return ret; 185 } else { 186 lvds_codec->bus_format = ret; 187 lvds_codec->bridge.funcs = &funcs_decoder; 188 } 189 } 190 191 /* 192 * Encoder might sample data on different clock edge than the display, 193 * for example OnSemi FIN3385 has a dedicated strapping pin to select 194 * the sampling edge. 195 */ 196 if (lvds_codec->connector_type == DRM_MODE_CONNECTOR_LVDS && 197 !of_property_read_u32(dev->of_node, "pclk-sample", &val)) { 198 lvds_codec->timings.input_bus_flags = val ? 199 DRM_BUS_FLAG_PIXDATA_SAMPLE_POSEDGE : 200 DRM_BUS_FLAG_PIXDATA_SAMPLE_NEGEDGE; 201 } 202 203 /* 204 * The panel_bridge bridge is attached to the panel's of_node, 205 * but we need a bridge attached to our of_node for our user 206 * to look up. 207 */ 208 lvds_codec->bridge.of_node = dev->of_node; 209 lvds_codec->bridge.timings = &lvds_codec->timings; 210 drm_bridge_add(&lvds_codec->bridge); 211 212 platform_set_drvdata(pdev, lvds_codec); 213 214 return 0; 215 } 216 217 static void lvds_codec_remove(struct platform_device *pdev) 218 { 219 struct lvds_codec *lvds_codec = platform_get_drvdata(pdev); 220 221 drm_bridge_remove(&lvds_codec->bridge); 222 } 223 224 static const struct of_device_id lvds_codec_match[] = { 225 { 226 .compatible = "lvds-decoder", 227 .data = (void *)DRM_MODE_CONNECTOR_DPI, 228 }, 229 { 230 .compatible = "lvds-encoder", 231 .data = (void *)DRM_MODE_CONNECTOR_LVDS, 232 }, 233 { 234 .compatible = "thine,thc63lvdm83d", 235 .data = (void *)DRM_MODE_CONNECTOR_LVDS, 236 }, 237 {}, 238 }; 239 MODULE_DEVICE_TABLE(of, lvds_codec_match); 240 241 static struct platform_driver lvds_codec_driver = { 242 .probe = lvds_codec_probe, 243 .remove_new = lvds_codec_remove, 244 .driver = { 245 .name = "lvds-codec", 246 .of_match_table = lvds_codec_match, 247 }, 248 }; 249 module_platform_driver(lvds_codec_driver); 250 251 MODULE_AUTHOR("Laurent Pinchart <laurent.pinchart@ideasonboard.com>"); 252 MODULE_DESCRIPTION("LVDS encoders and decoders"); 253 MODULE_LICENSE("GPL"); 254