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/delay.h> 8 #include <linux/fwnode.h> 9 #include <linux/gpio/consumer.h> 10 #include <linux/i2c.h> 11 #include <linux/irq.h> 12 #include <linux/module.h> 13 #include <linux/of_graph.h> 14 #include <linux/platform_device.h> 15 16 #include <drm/drm_atomic_helper.h> 17 #include <drm/drm_bridge.h> 18 #include <drm/drm_crtc.h> 19 #include <drm/drm_print.h> 20 #include <drm/drm_probe_helper.h> 21 22 #define HOTPLUG_DEBOUNCE_MS 1100 23 24 struct tfp410 { 25 struct drm_bridge bridge; 26 struct drm_connector connector; 27 unsigned int connector_type; 28 29 u32 bus_format; 30 struct i2c_adapter *ddc; 31 struct gpio_desc *hpd; 32 int hpd_irq; 33 struct delayed_work hpd_work; 34 struct gpio_desc *powerdown; 35 36 struct drm_bridge_timings timings; 37 38 struct device *dev; 39 }; 40 41 static inline struct tfp410 * 42 drm_bridge_to_tfp410(struct drm_bridge *bridge) 43 { 44 return container_of(bridge, struct tfp410, bridge); 45 } 46 47 static inline struct tfp410 * 48 drm_connector_to_tfp410(struct drm_connector *connector) 49 { 50 return container_of(connector, struct tfp410, connector); 51 } 52 53 static int tfp410_get_modes(struct drm_connector *connector) 54 { 55 struct tfp410 *dvi = drm_connector_to_tfp410(connector); 56 struct edid *edid; 57 int ret; 58 59 if (!dvi->ddc) 60 goto fallback; 61 62 edid = drm_get_edid(connector, dvi->ddc); 63 if (!edid) { 64 DRM_INFO("EDID read failed. Fallback to standard modes\n"); 65 goto fallback; 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 fallback: 77 /* No EDID, fallback on the XGA standard modes */ 78 ret = drm_add_modes_noedid(connector, 1920, 1200); 79 80 /* And prefer a mode pretty much anything can handle */ 81 drm_set_preferred_mode(connector, 1024, 768); 82 83 return ret; 84 } 85 86 static const struct drm_connector_helper_funcs tfp410_con_helper_funcs = { 87 .get_modes = tfp410_get_modes, 88 }; 89 90 static enum drm_connector_status 91 tfp410_connector_detect(struct drm_connector *connector, bool force) 92 { 93 struct tfp410 *dvi = drm_connector_to_tfp410(connector); 94 95 if (dvi->hpd) { 96 if (gpiod_get_value_cansleep(dvi->hpd)) 97 return connector_status_connected; 98 else 99 return connector_status_disconnected; 100 } 101 102 if (dvi->ddc) { 103 if (drm_probe_ddc(dvi->ddc)) 104 return connector_status_connected; 105 else 106 return connector_status_disconnected; 107 } 108 109 return connector_status_unknown; 110 } 111 112 static const struct drm_connector_funcs tfp410_con_funcs = { 113 .detect = tfp410_connector_detect, 114 .fill_modes = drm_helper_probe_single_connector_modes, 115 .destroy = drm_connector_cleanup, 116 .reset = drm_atomic_helper_connector_reset, 117 .atomic_duplicate_state = drm_atomic_helper_connector_duplicate_state, 118 .atomic_destroy_state = drm_atomic_helper_connector_destroy_state, 119 }; 120 121 static int tfp410_attach(struct drm_bridge *bridge) 122 { 123 struct tfp410 *dvi = drm_bridge_to_tfp410(bridge); 124 int ret; 125 126 if (!bridge->encoder) { 127 dev_err(dvi->dev, "Missing encoder\n"); 128 return -ENODEV; 129 } 130 131 if (dvi->hpd_irq >= 0) 132 dvi->connector.polled = DRM_CONNECTOR_POLL_HPD; 133 else 134 dvi->connector.polled = DRM_CONNECTOR_POLL_CONNECT | DRM_CONNECTOR_POLL_DISCONNECT; 135 136 drm_connector_helper_add(&dvi->connector, 137 &tfp410_con_helper_funcs); 138 ret = drm_connector_init_with_ddc(bridge->dev, &dvi->connector, 139 &tfp410_con_funcs, 140 dvi->connector_type, 141 dvi->ddc); 142 if (ret) { 143 dev_err(dvi->dev, "drm_connector_init_with_ddc() failed: %d\n", 144 ret); 145 return ret; 146 } 147 148 drm_display_info_set_bus_formats(&dvi->connector.display_info, 149 &dvi->bus_format, 1); 150 151 drm_connector_attach_encoder(&dvi->connector, 152 bridge->encoder); 153 154 return 0; 155 } 156 157 static void tfp410_enable(struct drm_bridge *bridge) 158 { 159 struct tfp410 *dvi = drm_bridge_to_tfp410(bridge); 160 161 gpiod_set_value_cansleep(dvi->powerdown, 0); 162 } 163 164 static void tfp410_disable(struct drm_bridge *bridge) 165 { 166 struct tfp410 *dvi = drm_bridge_to_tfp410(bridge); 167 168 gpiod_set_value_cansleep(dvi->powerdown, 1); 169 } 170 171 static const struct drm_bridge_funcs tfp410_bridge_funcs = { 172 .attach = tfp410_attach, 173 .enable = tfp410_enable, 174 .disable = tfp410_disable, 175 }; 176 177 static void tfp410_hpd_work_func(struct work_struct *work) 178 { 179 struct tfp410 *dvi; 180 181 dvi = container_of(work, struct tfp410, hpd_work.work); 182 183 if (dvi->bridge.dev) 184 drm_helper_hpd_irq_event(dvi->bridge.dev); 185 } 186 187 static irqreturn_t tfp410_hpd_irq_thread(int irq, void *arg) 188 { 189 struct tfp410 *dvi = arg; 190 191 mod_delayed_work(system_wq, &dvi->hpd_work, 192 msecs_to_jiffies(HOTPLUG_DEBOUNCE_MS)); 193 194 return IRQ_HANDLED; 195 } 196 197 static const struct drm_bridge_timings tfp410_default_timings = { 198 .input_bus_flags = DRM_BUS_FLAG_PIXDATA_SAMPLE_POSEDGE 199 | DRM_BUS_FLAG_DE_HIGH, 200 .setup_time_ps = 1200, 201 .hold_time_ps = 1300, 202 }; 203 204 static int tfp410_parse_timings(struct tfp410 *dvi, bool i2c) 205 { 206 struct drm_bridge_timings *timings = &dvi->timings; 207 struct device_node *ep; 208 u32 pclk_sample = 0; 209 u32 bus_width = 24; 210 s32 deskew = 0; 211 212 /* Start with defaults. */ 213 *timings = tfp410_default_timings; 214 215 if (i2c) 216 /* 217 * In I2C mode timings are configured through the I2C interface. 218 * As the driver doesn't support I2C configuration yet, we just 219 * go with the defaults (BSEL=1, DSEL=1, DKEN=0, EDGE=1). 220 */ 221 return 0; 222 223 /* 224 * In non-I2C mode, timings are configured through the BSEL, DSEL, DKEN 225 * and EDGE pins. They are specified in DT through endpoint properties 226 * and vendor-specific properties. 227 */ 228 ep = of_graph_get_endpoint_by_regs(dvi->dev->of_node, 0, 0); 229 if (!ep) 230 return -EINVAL; 231 232 /* Get the sampling edge from the endpoint. */ 233 of_property_read_u32(ep, "pclk-sample", &pclk_sample); 234 of_property_read_u32(ep, "bus-width", &bus_width); 235 of_node_put(ep); 236 237 timings->input_bus_flags = DRM_BUS_FLAG_DE_HIGH; 238 239 switch (pclk_sample) { 240 case 0: 241 timings->input_bus_flags |= DRM_BUS_FLAG_PIXDATA_SAMPLE_NEGEDGE 242 | DRM_BUS_FLAG_SYNC_SAMPLE_NEGEDGE; 243 break; 244 case 1: 245 timings->input_bus_flags |= DRM_BUS_FLAG_PIXDATA_SAMPLE_POSEDGE 246 | DRM_BUS_FLAG_SYNC_SAMPLE_POSEDGE; 247 break; 248 default: 249 return -EINVAL; 250 } 251 252 switch (bus_width) { 253 case 12: 254 dvi->bus_format = MEDIA_BUS_FMT_RGB888_2X12_LE; 255 break; 256 case 24: 257 dvi->bus_format = MEDIA_BUS_FMT_RGB888_1X24; 258 break; 259 default: 260 return -EINVAL; 261 } 262 263 /* Get the setup and hold time from vendor-specific properties. */ 264 of_property_read_u32(dvi->dev->of_node, "ti,deskew", (u32 *)&deskew); 265 if (deskew < -4 || deskew > 3) 266 return -EINVAL; 267 268 timings->setup_time_ps = min(0, 1200 - 350 * deskew); 269 timings->hold_time_ps = min(0, 1300 + 350 * deskew); 270 271 return 0; 272 } 273 274 static int tfp410_get_connector_properties(struct tfp410 *dvi) 275 { 276 struct device_node *connector_node, *ddc_phandle; 277 int ret = 0; 278 279 /* port@1 is the connector node */ 280 connector_node = of_graph_get_remote_node(dvi->dev->of_node, 1, -1); 281 if (!connector_node) 282 return -ENODEV; 283 284 if (of_device_is_compatible(connector_node, "hdmi-connector")) 285 dvi->connector_type = DRM_MODE_CONNECTOR_HDMIA; 286 else 287 dvi->connector_type = DRM_MODE_CONNECTOR_DVID; 288 289 dvi->hpd = fwnode_gpiod_get_index(&connector_node->fwnode, 290 "hpd", 0, GPIOD_IN, "hpd"); 291 if (IS_ERR(dvi->hpd)) { 292 ret = PTR_ERR(dvi->hpd); 293 dvi->hpd = NULL; 294 if (ret == -ENOENT) 295 ret = 0; 296 else 297 goto fail; 298 } 299 300 ddc_phandle = of_parse_phandle(connector_node, "ddc-i2c-bus", 0); 301 if (!ddc_phandle) 302 goto fail; 303 304 dvi->ddc = of_get_i2c_adapter_by_node(ddc_phandle); 305 if (dvi->ddc) 306 dev_info(dvi->dev, "Connector's ddc i2c bus found\n"); 307 else 308 ret = -EPROBE_DEFER; 309 310 of_node_put(ddc_phandle); 311 312 fail: 313 of_node_put(connector_node); 314 return ret; 315 } 316 317 static int tfp410_init(struct device *dev, bool i2c) 318 { 319 struct tfp410 *dvi; 320 int ret; 321 322 if (!dev->of_node) { 323 dev_err(dev, "device-tree data is missing\n"); 324 return -ENXIO; 325 } 326 327 dvi = devm_kzalloc(dev, sizeof(*dvi), GFP_KERNEL); 328 if (!dvi) 329 return -ENOMEM; 330 dev_set_drvdata(dev, dvi); 331 332 dvi->bridge.funcs = &tfp410_bridge_funcs; 333 dvi->bridge.of_node = dev->of_node; 334 dvi->bridge.timings = &dvi->timings; 335 dvi->dev = dev; 336 337 ret = tfp410_parse_timings(dvi, i2c); 338 if (ret) 339 goto fail; 340 341 ret = tfp410_get_connector_properties(dvi); 342 if (ret) 343 goto fail; 344 345 dvi->powerdown = devm_gpiod_get_optional(dev, "powerdown", 346 GPIOD_OUT_HIGH); 347 if (IS_ERR(dvi->powerdown)) { 348 dev_err(dev, "failed to parse powerdown gpio\n"); 349 return PTR_ERR(dvi->powerdown); 350 } 351 352 if (dvi->hpd) 353 dvi->hpd_irq = gpiod_to_irq(dvi->hpd); 354 else 355 dvi->hpd_irq = -ENXIO; 356 357 if (dvi->hpd_irq >= 0) { 358 INIT_DELAYED_WORK(&dvi->hpd_work, tfp410_hpd_work_func); 359 360 ret = devm_request_threaded_irq(dev, dvi->hpd_irq, 361 NULL, tfp410_hpd_irq_thread, IRQF_TRIGGER_RISING | 362 IRQF_TRIGGER_FALLING | IRQF_ONESHOT, 363 "hdmi-hpd", dvi); 364 if (ret) { 365 DRM_ERROR("failed to register hpd interrupt\n"); 366 goto fail; 367 } 368 } 369 370 drm_bridge_add(&dvi->bridge); 371 372 return 0; 373 fail: 374 i2c_put_adapter(dvi->ddc); 375 if (dvi->hpd) 376 gpiod_put(dvi->hpd); 377 return ret; 378 } 379 380 static int tfp410_fini(struct device *dev) 381 { 382 struct tfp410 *dvi = dev_get_drvdata(dev); 383 384 if (dvi->hpd_irq >= 0) 385 cancel_delayed_work_sync(&dvi->hpd_work); 386 387 drm_bridge_remove(&dvi->bridge); 388 389 if (dvi->ddc) 390 i2c_put_adapter(dvi->ddc); 391 if (dvi->hpd) 392 gpiod_put(dvi->hpd); 393 394 return 0; 395 } 396 397 static int tfp410_probe(struct platform_device *pdev) 398 { 399 return tfp410_init(&pdev->dev, false); 400 } 401 402 static int tfp410_remove(struct platform_device *pdev) 403 { 404 return tfp410_fini(&pdev->dev); 405 } 406 407 static const struct of_device_id tfp410_match[] = { 408 { .compatible = "ti,tfp410" }, 409 {}, 410 }; 411 MODULE_DEVICE_TABLE(of, tfp410_match); 412 413 static struct platform_driver tfp410_platform_driver = { 414 .probe = tfp410_probe, 415 .remove = tfp410_remove, 416 .driver = { 417 .name = "tfp410-bridge", 418 .of_match_table = tfp410_match, 419 }, 420 }; 421 422 #if IS_ENABLED(CONFIG_I2C) 423 /* There is currently no i2c functionality. */ 424 static int tfp410_i2c_probe(struct i2c_client *client, 425 const struct i2c_device_id *id) 426 { 427 int reg; 428 429 if (!client->dev.of_node || 430 of_property_read_u32(client->dev.of_node, "reg", ®)) { 431 dev_err(&client->dev, 432 "Can't get i2c reg property from device-tree\n"); 433 return -ENXIO; 434 } 435 436 return tfp410_init(&client->dev, true); 437 } 438 439 static int tfp410_i2c_remove(struct i2c_client *client) 440 { 441 return tfp410_fini(&client->dev); 442 } 443 444 static const struct i2c_device_id tfp410_i2c_ids[] = { 445 { "tfp410", 0 }, 446 { } 447 }; 448 MODULE_DEVICE_TABLE(i2c, tfp410_i2c_ids); 449 450 static struct i2c_driver tfp410_i2c_driver = { 451 .driver = { 452 .name = "tfp410", 453 .of_match_table = of_match_ptr(tfp410_match), 454 }, 455 .id_table = tfp410_i2c_ids, 456 .probe = tfp410_i2c_probe, 457 .remove = tfp410_i2c_remove, 458 }; 459 #endif /* IS_ENABLED(CONFIG_I2C) */ 460 461 static struct { 462 uint i2c:1; 463 uint platform:1; 464 } tfp410_registered_driver; 465 466 static int __init tfp410_module_init(void) 467 { 468 int ret; 469 470 #if IS_ENABLED(CONFIG_I2C) 471 ret = i2c_add_driver(&tfp410_i2c_driver); 472 if (ret) 473 pr_err("%s: registering i2c driver failed: %d", 474 __func__, ret); 475 else 476 tfp410_registered_driver.i2c = 1; 477 #endif 478 479 ret = platform_driver_register(&tfp410_platform_driver); 480 if (ret) 481 pr_err("%s: registering platform driver failed: %d", 482 __func__, ret); 483 else 484 tfp410_registered_driver.platform = 1; 485 486 if (tfp410_registered_driver.i2c || 487 tfp410_registered_driver.platform) 488 return 0; 489 490 return ret; 491 } 492 module_init(tfp410_module_init); 493 494 static void __exit tfp410_module_exit(void) 495 { 496 #if IS_ENABLED(CONFIG_I2C) 497 if (tfp410_registered_driver.i2c) 498 i2c_del_driver(&tfp410_i2c_driver); 499 #endif 500 if (tfp410_registered_driver.platform) 501 platform_driver_unregister(&tfp410_platform_driver); 502 } 503 module_exit(tfp410_module_exit); 504 505 MODULE_AUTHOR("Jyri Sarha <jsarha@ti.com>"); 506 MODULE_DESCRIPTION("TI TFP410 DVI bridge driver"); 507 MODULE_LICENSE("GPL"); 508