1 // SPDX-License-Identifier: GPL-2.0-only 2 /* 3 * Copyright (C) 2016 Texas Instruments 4 * Author: Jyri Sarha <jsarha@ti.com> 5 */ 6 7 #include <linux/gpio/consumer.h> 8 #include <linux/i2c.h> 9 #include <linux/module.h> 10 #include <linux/of_graph.h> 11 #include <linux/platform_device.h> 12 #include <linux/workqueue.h> 13 14 #include <drm/drm_atomic_helper.h> 15 #include <drm/drm_bridge.h> 16 #include <drm/drm_crtc.h> 17 #include <drm/drm_print.h> 18 #include <drm/drm_probe_helper.h> 19 20 #define HOTPLUG_DEBOUNCE_MS 1100 21 22 struct tfp410 { 23 struct drm_bridge bridge; 24 struct drm_connector connector; 25 26 u32 bus_format; 27 struct delayed_work hpd_work; 28 struct gpio_desc *powerdown; 29 30 struct drm_bridge_timings timings; 31 struct drm_bridge *next_bridge; 32 33 struct device *dev; 34 }; 35 36 static inline struct tfp410 * 37 drm_bridge_to_tfp410(struct drm_bridge *bridge) 38 { 39 return container_of(bridge, struct tfp410, bridge); 40 } 41 42 static inline struct tfp410 * 43 drm_connector_to_tfp410(struct drm_connector *connector) 44 { 45 return container_of(connector, struct tfp410, connector); 46 } 47 48 static int tfp410_get_modes(struct drm_connector *connector) 49 { 50 struct tfp410 *dvi = drm_connector_to_tfp410(connector); 51 struct edid *edid; 52 int ret; 53 54 edid = drm_bridge_get_edid(dvi->next_bridge, connector); 55 if (IS_ERR_OR_NULL(edid)) { 56 if (edid != ERR_PTR(-ENOTSUPP)) 57 DRM_INFO("EDID read failed. Fallback to standard modes\n"); 58 59 /* 60 * No EDID, fallback on the XGA standard modes and prefer a mode 61 * pretty much anything can handle. 62 */ 63 ret = drm_add_modes_noedid(connector, 1920, 1200); 64 drm_set_preferred_mode(connector, 1024, 768); 65 return ret; 66 } 67 68 drm_connector_update_edid_property(connector, edid); 69 70 ret = drm_add_edid_modes(connector, edid); 71 72 kfree(edid); 73 74 return ret; 75 } 76 77 static const struct drm_connector_helper_funcs tfp410_con_helper_funcs = { 78 .get_modes = tfp410_get_modes, 79 }; 80 81 static enum drm_connector_status 82 tfp410_connector_detect(struct drm_connector *connector, bool force) 83 { 84 struct tfp410 *dvi = drm_connector_to_tfp410(connector); 85 86 return drm_bridge_detect(dvi->next_bridge); 87 } 88 89 static const struct drm_connector_funcs tfp410_con_funcs = { 90 .detect = tfp410_connector_detect, 91 .fill_modes = drm_helper_probe_single_connector_modes, 92 .destroy = drm_connector_cleanup, 93 .reset = drm_atomic_helper_connector_reset, 94 .atomic_duplicate_state = drm_atomic_helper_connector_duplicate_state, 95 .atomic_destroy_state = drm_atomic_helper_connector_destroy_state, 96 }; 97 98 static void tfp410_hpd_work_func(struct work_struct *work) 99 { 100 struct tfp410 *dvi; 101 102 dvi = container_of(work, struct tfp410, hpd_work.work); 103 104 if (dvi->bridge.dev) 105 drm_helper_hpd_irq_event(dvi->bridge.dev); 106 } 107 108 static void tfp410_hpd_callback(void *arg, enum drm_connector_status status) 109 { 110 struct tfp410 *dvi = arg; 111 112 mod_delayed_work(system_wq, &dvi->hpd_work, 113 msecs_to_jiffies(HOTPLUG_DEBOUNCE_MS)); 114 } 115 116 static int tfp410_attach(struct drm_bridge *bridge, 117 enum drm_bridge_attach_flags flags) 118 { 119 struct tfp410 *dvi = drm_bridge_to_tfp410(bridge); 120 int ret; 121 122 ret = drm_bridge_attach(bridge->encoder, dvi->next_bridge, bridge, 123 DRM_BRIDGE_ATTACH_NO_CONNECTOR); 124 if (ret < 0) 125 return ret; 126 127 if (flags & DRM_BRIDGE_ATTACH_NO_CONNECTOR) 128 return 0; 129 130 if (!bridge->encoder) { 131 dev_err(dvi->dev, "Missing encoder\n"); 132 return -ENODEV; 133 } 134 135 if (dvi->next_bridge->ops & DRM_BRIDGE_OP_DETECT) 136 dvi->connector.polled = DRM_CONNECTOR_POLL_HPD; 137 else 138 dvi->connector.polled = DRM_CONNECTOR_POLL_CONNECT | DRM_CONNECTOR_POLL_DISCONNECT; 139 140 if (dvi->next_bridge->ops & DRM_BRIDGE_OP_HPD) { 141 INIT_DELAYED_WORK(&dvi->hpd_work, tfp410_hpd_work_func); 142 drm_bridge_hpd_enable(dvi->next_bridge, tfp410_hpd_callback, 143 dvi); 144 } 145 146 drm_connector_helper_add(&dvi->connector, 147 &tfp410_con_helper_funcs); 148 ret = drm_connector_init_with_ddc(bridge->dev, &dvi->connector, 149 &tfp410_con_funcs, 150 dvi->next_bridge->type, 151 dvi->next_bridge->ddc); 152 if (ret) { 153 dev_err(dvi->dev, "drm_connector_init() failed: %d\n", ret); 154 return ret; 155 } 156 157 drm_display_info_set_bus_formats(&dvi->connector.display_info, 158 &dvi->bus_format, 1); 159 160 drm_connector_attach_encoder(&dvi->connector, bridge->encoder); 161 162 return 0; 163 } 164 165 static void tfp410_detach(struct drm_bridge *bridge) 166 { 167 struct tfp410 *dvi = drm_bridge_to_tfp410(bridge); 168 169 if (dvi->connector.dev && dvi->next_bridge->ops & DRM_BRIDGE_OP_HPD) { 170 drm_bridge_hpd_disable(dvi->next_bridge); 171 cancel_delayed_work_sync(&dvi->hpd_work); 172 } 173 } 174 175 static void tfp410_enable(struct drm_bridge *bridge) 176 { 177 struct tfp410 *dvi = drm_bridge_to_tfp410(bridge); 178 179 gpiod_set_value_cansleep(dvi->powerdown, 0); 180 } 181 182 static void tfp410_disable(struct drm_bridge *bridge) 183 { 184 struct tfp410 *dvi = drm_bridge_to_tfp410(bridge); 185 186 gpiod_set_value_cansleep(dvi->powerdown, 1); 187 } 188 189 static enum drm_mode_status tfp410_mode_valid(struct drm_bridge *bridge, 190 const struct drm_display_mode *mode) 191 { 192 if (mode->clock < 25000) 193 return MODE_CLOCK_LOW; 194 195 if (mode->clock > 165000) 196 return MODE_CLOCK_HIGH; 197 198 return MODE_OK; 199 } 200 201 static const struct drm_bridge_funcs tfp410_bridge_funcs = { 202 .attach = tfp410_attach, 203 .detach = tfp410_detach, 204 .enable = tfp410_enable, 205 .disable = tfp410_disable, 206 .mode_valid = tfp410_mode_valid, 207 }; 208 209 static const struct drm_bridge_timings tfp410_default_timings = { 210 .input_bus_flags = DRM_BUS_FLAG_PIXDATA_SAMPLE_POSEDGE 211 | DRM_BUS_FLAG_DE_HIGH, 212 .setup_time_ps = 1200, 213 .hold_time_ps = 1300, 214 }; 215 216 static int tfp410_parse_timings(struct tfp410 *dvi, bool i2c) 217 { 218 struct drm_bridge_timings *timings = &dvi->timings; 219 struct device_node *ep; 220 u32 pclk_sample = 0; 221 u32 bus_width = 24; 222 s32 deskew = 0; 223 224 /* Start with defaults. */ 225 *timings = tfp410_default_timings; 226 227 if (i2c) 228 /* 229 * In I2C mode timings are configured through the I2C interface. 230 * As the driver doesn't support I2C configuration yet, we just 231 * go with the defaults (BSEL=1, DSEL=1, DKEN=0, EDGE=1). 232 */ 233 return 0; 234 235 /* 236 * In non-I2C mode, timings are configured through the BSEL, DSEL, DKEN 237 * and EDGE pins. They are specified in DT through endpoint properties 238 * and vendor-specific properties. 239 */ 240 ep = of_graph_get_endpoint_by_regs(dvi->dev->of_node, 0, 0); 241 if (!ep) 242 return -EINVAL; 243 244 /* Get the sampling edge from the endpoint. */ 245 of_property_read_u32(ep, "pclk-sample", &pclk_sample); 246 of_property_read_u32(ep, "bus-width", &bus_width); 247 of_node_put(ep); 248 249 timings->input_bus_flags = DRM_BUS_FLAG_DE_HIGH; 250 251 switch (pclk_sample) { 252 case 0: 253 timings->input_bus_flags |= DRM_BUS_FLAG_PIXDATA_SAMPLE_NEGEDGE 254 | DRM_BUS_FLAG_SYNC_SAMPLE_NEGEDGE; 255 break; 256 case 1: 257 timings->input_bus_flags |= DRM_BUS_FLAG_PIXDATA_SAMPLE_POSEDGE 258 | DRM_BUS_FLAG_SYNC_SAMPLE_POSEDGE; 259 break; 260 default: 261 return -EINVAL; 262 } 263 264 switch (bus_width) { 265 case 12: 266 dvi->bus_format = MEDIA_BUS_FMT_RGB888_2X12_LE; 267 break; 268 case 24: 269 dvi->bus_format = MEDIA_BUS_FMT_RGB888_1X24; 270 break; 271 default: 272 return -EINVAL; 273 } 274 275 /* Get the setup and hold time from vendor-specific properties. */ 276 of_property_read_u32(dvi->dev->of_node, "ti,deskew", (u32 *)&deskew); 277 if (deskew < -4 || deskew > 3) 278 return -EINVAL; 279 280 timings->setup_time_ps = min(0, 1200 - 350 * deskew); 281 timings->hold_time_ps = min(0, 1300 + 350 * deskew); 282 283 return 0; 284 } 285 286 static int tfp410_init(struct device *dev, bool i2c) 287 { 288 struct device_node *node; 289 struct tfp410 *dvi; 290 int ret; 291 292 if (!dev->of_node) { 293 dev_err(dev, "device-tree data is missing\n"); 294 return -ENXIO; 295 } 296 297 dvi = devm_kzalloc(dev, sizeof(*dvi), GFP_KERNEL); 298 if (!dvi) 299 return -ENOMEM; 300 301 dvi->dev = dev; 302 dev_set_drvdata(dev, dvi); 303 304 dvi->bridge.funcs = &tfp410_bridge_funcs; 305 dvi->bridge.of_node = dev->of_node; 306 dvi->bridge.timings = &dvi->timings; 307 dvi->bridge.type = DRM_MODE_CONNECTOR_DVID; 308 309 ret = tfp410_parse_timings(dvi, i2c); 310 if (ret) 311 return ret; 312 313 /* Get the next bridge, connected to port@1. */ 314 node = of_graph_get_remote_node(dev->of_node, 1, -1); 315 if (!node) 316 return -ENODEV; 317 318 dvi->next_bridge = of_drm_find_bridge(node); 319 of_node_put(node); 320 321 if (!dvi->next_bridge) 322 return -EPROBE_DEFER; 323 324 /* Get the powerdown GPIO. */ 325 dvi->powerdown = devm_gpiod_get_optional(dev, "powerdown", 326 GPIOD_OUT_HIGH); 327 if (IS_ERR(dvi->powerdown)) { 328 dev_err(dev, "failed to parse powerdown gpio\n"); 329 return PTR_ERR(dvi->powerdown); 330 } 331 332 /* Register the DRM bridge. */ 333 drm_bridge_add(&dvi->bridge); 334 335 return 0; 336 } 337 338 static int tfp410_fini(struct device *dev) 339 { 340 struct tfp410 *dvi = dev_get_drvdata(dev); 341 342 drm_bridge_remove(&dvi->bridge); 343 344 return 0; 345 } 346 347 static int tfp410_probe(struct platform_device *pdev) 348 { 349 return tfp410_init(&pdev->dev, false); 350 } 351 352 static int tfp410_remove(struct platform_device *pdev) 353 { 354 return tfp410_fini(&pdev->dev); 355 } 356 357 static const struct of_device_id tfp410_match[] = { 358 { .compatible = "ti,tfp410" }, 359 {}, 360 }; 361 MODULE_DEVICE_TABLE(of, tfp410_match); 362 363 static struct platform_driver tfp410_platform_driver = { 364 .probe = tfp410_probe, 365 .remove = tfp410_remove, 366 .driver = { 367 .name = "tfp410-bridge", 368 .of_match_table = tfp410_match, 369 }, 370 }; 371 372 #if IS_ENABLED(CONFIG_I2C) 373 /* There is currently no i2c functionality. */ 374 static int tfp410_i2c_probe(struct i2c_client *client, 375 const struct i2c_device_id *id) 376 { 377 int reg; 378 379 if (!client->dev.of_node || 380 of_property_read_u32(client->dev.of_node, "reg", ®)) { 381 dev_err(&client->dev, 382 "Can't get i2c reg property from device-tree\n"); 383 return -ENXIO; 384 } 385 386 return tfp410_init(&client->dev, true); 387 } 388 389 static int tfp410_i2c_remove(struct i2c_client *client) 390 { 391 return tfp410_fini(&client->dev); 392 } 393 394 static const struct i2c_device_id tfp410_i2c_ids[] = { 395 { "tfp410", 0 }, 396 { } 397 }; 398 MODULE_DEVICE_TABLE(i2c, tfp410_i2c_ids); 399 400 static struct i2c_driver tfp410_i2c_driver = { 401 .driver = { 402 .name = "tfp410", 403 .of_match_table = of_match_ptr(tfp410_match), 404 }, 405 .id_table = tfp410_i2c_ids, 406 .probe = tfp410_i2c_probe, 407 .remove = tfp410_i2c_remove, 408 }; 409 #endif /* IS_ENABLED(CONFIG_I2C) */ 410 411 static struct { 412 uint i2c:1; 413 uint platform:1; 414 } tfp410_registered_driver; 415 416 static int __init tfp410_module_init(void) 417 { 418 int ret; 419 420 #if IS_ENABLED(CONFIG_I2C) 421 ret = i2c_add_driver(&tfp410_i2c_driver); 422 if (ret) 423 pr_err("%s: registering i2c driver failed: %d", 424 __func__, ret); 425 else 426 tfp410_registered_driver.i2c = 1; 427 #endif 428 429 ret = platform_driver_register(&tfp410_platform_driver); 430 if (ret) 431 pr_err("%s: registering platform driver failed: %d", 432 __func__, ret); 433 else 434 tfp410_registered_driver.platform = 1; 435 436 if (tfp410_registered_driver.i2c || 437 tfp410_registered_driver.platform) 438 return 0; 439 440 return ret; 441 } 442 module_init(tfp410_module_init); 443 444 static void __exit tfp410_module_exit(void) 445 { 446 #if IS_ENABLED(CONFIG_I2C) 447 if (tfp410_registered_driver.i2c) 448 i2c_del_driver(&tfp410_i2c_driver); 449 #endif 450 if (tfp410_registered_driver.platform) 451 platform_driver_unregister(&tfp410_platform_driver); 452 } 453 module_exit(tfp410_module_exit); 454 455 MODULE_AUTHOR("Jyri Sarha <jsarha@ti.com>"); 456 MODULE_DESCRIPTION("TI TFP410 DVI bridge driver"); 457 MODULE_LICENSE("GPL"); 458