1 /* 2 * Copyright (C) 2016 Texas Instruments 3 * Author: Jyri Sarha <jsarha@ti.com> 4 * 5 * This program is free software; you can redistribute it and/or modify it 6 * under the terms of the GNU General Public License version 2 as published by 7 * the Free Software Foundation. 8 * 9 */ 10 11 #include <linux/delay.h> 12 #include <linux/fwnode.h> 13 #include <linux/gpio/consumer.h> 14 #include <linux/irq.h> 15 #include <linux/module.h> 16 #include <linux/of_graph.h> 17 #include <linux/platform_device.h> 18 #include <linux/i2c.h> 19 20 #include <drm/drmP.h> 21 #include <drm/drm_atomic_helper.h> 22 #include <drm/drm_crtc.h> 23 #include <drm/drm_probe_helper.h> 24 25 #define HOTPLUG_DEBOUNCE_MS 1100 26 27 struct tfp410 { 28 struct drm_bridge bridge; 29 struct drm_connector connector; 30 unsigned int connector_type; 31 32 u32 bus_format; 33 struct i2c_adapter *ddc; 34 struct gpio_desc *hpd; 35 int hpd_irq; 36 struct delayed_work hpd_work; 37 struct gpio_desc *powerdown; 38 39 struct drm_bridge_timings timings; 40 41 struct device *dev; 42 }; 43 44 static inline struct tfp410 * 45 drm_bridge_to_tfp410(struct drm_bridge *bridge) 46 { 47 return container_of(bridge, struct tfp410, bridge); 48 } 49 50 static inline struct tfp410 * 51 drm_connector_to_tfp410(struct drm_connector *connector) 52 { 53 return container_of(connector, struct tfp410, connector); 54 } 55 56 static int tfp410_get_modes(struct drm_connector *connector) 57 { 58 struct tfp410 *dvi = drm_connector_to_tfp410(connector); 59 struct edid *edid; 60 int ret; 61 62 if (!dvi->ddc) 63 goto fallback; 64 65 edid = drm_get_edid(connector, dvi->ddc); 66 if (!edid) { 67 DRM_INFO("EDID read failed. Fallback to standard modes\n"); 68 goto fallback; 69 } 70 71 drm_connector_update_edid_property(connector, edid); 72 73 return drm_add_edid_modes(connector, edid); 74 fallback: 75 /* No EDID, fallback on the XGA standard modes */ 76 ret = drm_add_modes_noedid(connector, 1920, 1200); 77 78 /* And prefer a mode pretty much anything can handle */ 79 drm_set_preferred_mode(connector, 1024, 768); 80 81 return ret; 82 } 83 84 static const struct drm_connector_helper_funcs tfp410_con_helper_funcs = { 85 .get_modes = tfp410_get_modes, 86 }; 87 88 static enum drm_connector_status 89 tfp410_connector_detect(struct drm_connector *connector, bool force) 90 { 91 struct tfp410 *dvi = drm_connector_to_tfp410(connector); 92 93 if (dvi->hpd) { 94 if (gpiod_get_value_cansleep(dvi->hpd)) 95 return connector_status_connected; 96 else 97 return connector_status_disconnected; 98 } 99 100 if (dvi->ddc) { 101 if (drm_probe_ddc(dvi->ddc)) 102 return connector_status_connected; 103 else 104 return connector_status_disconnected; 105 } 106 107 return connector_status_unknown; 108 } 109 110 static const struct drm_connector_funcs tfp410_con_funcs = { 111 .detect = tfp410_connector_detect, 112 .fill_modes = drm_helper_probe_single_connector_modes, 113 .destroy = drm_connector_cleanup, 114 .reset = drm_atomic_helper_connector_reset, 115 .atomic_duplicate_state = drm_atomic_helper_connector_duplicate_state, 116 .atomic_destroy_state = drm_atomic_helper_connector_destroy_state, 117 }; 118 119 static int tfp410_attach(struct drm_bridge *bridge) 120 { 121 struct tfp410 *dvi = drm_bridge_to_tfp410(bridge); 122 int ret; 123 124 if (!bridge->encoder) { 125 dev_err(dvi->dev, "Missing encoder\n"); 126 return -ENODEV; 127 } 128 129 if (dvi->hpd_irq >= 0) 130 dvi->connector.polled = DRM_CONNECTOR_POLL_HPD; 131 else 132 dvi->connector.polled = DRM_CONNECTOR_POLL_CONNECT | DRM_CONNECTOR_POLL_DISCONNECT; 133 134 drm_connector_helper_add(&dvi->connector, 135 &tfp410_con_helper_funcs); 136 ret = drm_connector_init(bridge->dev, &dvi->connector, 137 &tfp410_con_funcs, dvi->connector_type); 138 if (ret) { 139 dev_err(dvi->dev, "drm_connector_init() failed: %d\n", ret); 140 return ret; 141 } 142 143 drm_display_info_set_bus_formats(&dvi->connector.display_info, 144 &dvi->bus_format, 1); 145 146 drm_connector_attach_encoder(&dvi->connector, 147 bridge->encoder); 148 149 return 0; 150 } 151 152 static void tfp410_enable(struct drm_bridge *bridge) 153 { 154 struct tfp410 *dvi = drm_bridge_to_tfp410(bridge); 155 156 gpiod_set_value_cansleep(dvi->powerdown, 0); 157 } 158 159 static void tfp410_disable(struct drm_bridge *bridge) 160 { 161 struct tfp410 *dvi = drm_bridge_to_tfp410(bridge); 162 163 gpiod_set_value_cansleep(dvi->powerdown, 1); 164 } 165 166 static const struct drm_bridge_funcs tfp410_bridge_funcs = { 167 .attach = tfp410_attach, 168 .enable = tfp410_enable, 169 .disable = tfp410_disable, 170 }; 171 172 static void tfp410_hpd_work_func(struct work_struct *work) 173 { 174 struct tfp410 *dvi; 175 176 dvi = container_of(work, struct tfp410, hpd_work.work); 177 178 if (dvi->bridge.dev) 179 drm_helper_hpd_irq_event(dvi->bridge.dev); 180 } 181 182 static irqreturn_t tfp410_hpd_irq_thread(int irq, void *arg) 183 { 184 struct tfp410 *dvi = arg; 185 186 mod_delayed_work(system_wq, &dvi->hpd_work, 187 msecs_to_jiffies(HOTPLUG_DEBOUNCE_MS)); 188 189 return IRQ_HANDLED; 190 } 191 192 static const struct drm_bridge_timings tfp410_default_timings = { 193 .input_bus_flags = DRM_BUS_FLAG_PIXDATA_SAMPLE_POSEDGE 194 | DRM_BUS_FLAG_DE_HIGH, 195 .setup_time_ps = 1200, 196 .hold_time_ps = 1300, 197 }; 198 199 static int tfp410_parse_timings(struct tfp410 *dvi, bool i2c) 200 { 201 struct drm_bridge_timings *timings = &dvi->timings; 202 struct device_node *ep; 203 u32 pclk_sample = 0; 204 u32 bus_width = 24; 205 s32 deskew = 0; 206 207 /* Start with defaults. */ 208 *timings = tfp410_default_timings; 209 210 if (i2c) 211 /* 212 * In I2C mode timings are configured through the I2C interface. 213 * As the driver doesn't support I2C configuration yet, we just 214 * go with the defaults (BSEL=1, DSEL=1, DKEN=0, EDGE=1). 215 */ 216 return 0; 217 218 /* 219 * In non-I2C mode, timings are configured through the BSEL, DSEL, DKEN 220 * and EDGE pins. They are specified in DT through endpoint properties 221 * and vendor-specific properties. 222 */ 223 ep = of_graph_get_endpoint_by_regs(dvi->dev->of_node, 0, 0); 224 if (!ep) 225 return -EINVAL; 226 227 /* Get the sampling edge from the endpoint. */ 228 of_property_read_u32(ep, "pclk-sample", &pclk_sample); 229 of_property_read_u32(ep, "bus-width", &bus_width); 230 of_node_put(ep); 231 232 timings->input_bus_flags = DRM_BUS_FLAG_DE_HIGH; 233 234 switch (pclk_sample) { 235 case 0: 236 timings->input_bus_flags |= DRM_BUS_FLAG_PIXDATA_SAMPLE_NEGEDGE 237 | DRM_BUS_FLAG_SYNC_SAMPLE_NEGEDGE; 238 break; 239 case 1: 240 timings->input_bus_flags |= DRM_BUS_FLAG_PIXDATA_SAMPLE_POSEDGE 241 | DRM_BUS_FLAG_SYNC_SAMPLE_POSEDGE; 242 break; 243 default: 244 return -EINVAL; 245 } 246 247 switch (bus_width) { 248 case 12: 249 dvi->bus_format = MEDIA_BUS_FMT_RGB888_2X12_LE; 250 break; 251 case 24: 252 dvi->bus_format = MEDIA_BUS_FMT_RGB888_1X24; 253 break; 254 default: 255 return -EINVAL; 256 } 257 258 /* Get the setup and hold time from vendor-specific properties. */ 259 of_property_read_u32(dvi->dev->of_node, "ti,deskew", (u32 *)&deskew); 260 if (deskew < -4 || deskew > 3) 261 return -EINVAL; 262 263 timings->setup_time_ps = min(0, 1200 - 350 * deskew); 264 timings->hold_time_ps = min(0, 1300 + 350 * deskew); 265 266 return 0; 267 } 268 269 static int tfp410_get_connector_properties(struct tfp410 *dvi) 270 { 271 struct device_node *connector_node, *ddc_phandle; 272 int ret = 0; 273 274 /* port@1 is the connector node */ 275 connector_node = of_graph_get_remote_node(dvi->dev->of_node, 1, -1); 276 if (!connector_node) 277 return -ENODEV; 278 279 if (of_device_is_compatible(connector_node, "hdmi-connector")) 280 dvi->connector_type = DRM_MODE_CONNECTOR_HDMIA; 281 else 282 dvi->connector_type = DRM_MODE_CONNECTOR_DVID; 283 284 dvi->hpd = fwnode_get_named_gpiod(&connector_node->fwnode, 285 "hpd-gpios", 0, GPIOD_IN, "hpd"); 286 if (IS_ERR(dvi->hpd)) { 287 ret = PTR_ERR(dvi->hpd); 288 dvi->hpd = NULL; 289 if (ret == -ENOENT) 290 ret = 0; 291 else 292 goto fail; 293 } 294 295 ddc_phandle = of_parse_phandle(connector_node, "ddc-i2c-bus", 0); 296 if (!ddc_phandle) 297 goto fail; 298 299 dvi->ddc = of_get_i2c_adapter_by_node(ddc_phandle); 300 if (dvi->ddc) 301 dev_info(dvi->dev, "Connector's ddc i2c bus found\n"); 302 else 303 ret = -EPROBE_DEFER; 304 305 of_node_put(ddc_phandle); 306 307 fail: 308 of_node_put(connector_node); 309 return ret; 310 } 311 312 static int tfp410_init(struct device *dev, bool i2c) 313 { 314 struct tfp410 *dvi; 315 int ret; 316 317 if (!dev->of_node) { 318 dev_err(dev, "device-tree data is missing\n"); 319 return -ENXIO; 320 } 321 322 dvi = devm_kzalloc(dev, sizeof(*dvi), GFP_KERNEL); 323 if (!dvi) 324 return -ENOMEM; 325 dev_set_drvdata(dev, dvi); 326 327 dvi->bridge.funcs = &tfp410_bridge_funcs; 328 dvi->bridge.of_node = dev->of_node; 329 dvi->bridge.timings = &dvi->timings; 330 dvi->dev = dev; 331 332 ret = tfp410_parse_timings(dvi, i2c); 333 if (ret) 334 goto fail; 335 336 ret = tfp410_get_connector_properties(dvi); 337 if (ret) 338 goto fail; 339 340 dvi->powerdown = devm_gpiod_get_optional(dev, "powerdown", 341 GPIOD_OUT_HIGH); 342 if (IS_ERR(dvi->powerdown)) { 343 dev_err(dev, "failed to parse powerdown gpio\n"); 344 return PTR_ERR(dvi->powerdown); 345 } 346 347 if (dvi->hpd) 348 dvi->hpd_irq = gpiod_to_irq(dvi->hpd); 349 else 350 dvi->hpd_irq = -ENXIO; 351 352 if (dvi->hpd_irq >= 0) { 353 INIT_DELAYED_WORK(&dvi->hpd_work, tfp410_hpd_work_func); 354 355 ret = devm_request_threaded_irq(dev, dvi->hpd_irq, 356 NULL, tfp410_hpd_irq_thread, IRQF_TRIGGER_RISING | 357 IRQF_TRIGGER_FALLING | IRQF_ONESHOT, 358 "hdmi-hpd", dvi); 359 if (ret) { 360 DRM_ERROR("failed to register hpd interrupt\n"); 361 goto fail; 362 } 363 } 364 365 drm_bridge_add(&dvi->bridge); 366 367 return 0; 368 fail: 369 i2c_put_adapter(dvi->ddc); 370 if (dvi->hpd) 371 gpiod_put(dvi->hpd); 372 return ret; 373 } 374 375 static int tfp410_fini(struct device *dev) 376 { 377 struct tfp410 *dvi = dev_get_drvdata(dev); 378 379 cancel_delayed_work_sync(&dvi->hpd_work); 380 381 drm_bridge_remove(&dvi->bridge); 382 383 if (dvi->ddc) 384 i2c_put_adapter(dvi->ddc); 385 if (dvi->hpd) 386 gpiod_put(dvi->hpd); 387 388 return 0; 389 } 390 391 static int tfp410_probe(struct platform_device *pdev) 392 { 393 return tfp410_init(&pdev->dev, false); 394 } 395 396 static int tfp410_remove(struct platform_device *pdev) 397 { 398 return tfp410_fini(&pdev->dev); 399 } 400 401 static const struct of_device_id tfp410_match[] = { 402 { .compatible = "ti,tfp410" }, 403 {}, 404 }; 405 MODULE_DEVICE_TABLE(of, tfp410_match); 406 407 static struct platform_driver tfp410_platform_driver = { 408 .probe = tfp410_probe, 409 .remove = tfp410_remove, 410 .driver = { 411 .name = "tfp410-bridge", 412 .of_match_table = tfp410_match, 413 }, 414 }; 415 416 #if IS_ENABLED(CONFIG_I2C) 417 /* There is currently no i2c functionality. */ 418 static int tfp410_i2c_probe(struct i2c_client *client, 419 const struct i2c_device_id *id) 420 { 421 int reg; 422 423 if (!client->dev.of_node || 424 of_property_read_u32(client->dev.of_node, "reg", ®)) { 425 dev_err(&client->dev, 426 "Can't get i2c reg property from device-tree\n"); 427 return -ENXIO; 428 } 429 430 return tfp410_init(&client->dev, true); 431 } 432 433 static int tfp410_i2c_remove(struct i2c_client *client) 434 { 435 return tfp410_fini(&client->dev); 436 } 437 438 static const struct i2c_device_id tfp410_i2c_ids[] = { 439 { "tfp410", 0 }, 440 { } 441 }; 442 MODULE_DEVICE_TABLE(i2c, tfp410_i2c_ids); 443 444 static struct i2c_driver tfp410_i2c_driver = { 445 .driver = { 446 .name = "tfp410", 447 .of_match_table = of_match_ptr(tfp410_match), 448 }, 449 .id_table = tfp410_i2c_ids, 450 .probe = tfp410_i2c_probe, 451 .remove = tfp410_i2c_remove, 452 }; 453 #endif /* IS_ENABLED(CONFIG_I2C) */ 454 455 static struct { 456 uint i2c:1; 457 uint platform:1; 458 } tfp410_registered_driver; 459 460 static int __init tfp410_module_init(void) 461 { 462 int ret; 463 464 #if IS_ENABLED(CONFIG_I2C) 465 ret = i2c_add_driver(&tfp410_i2c_driver); 466 if (ret) 467 pr_err("%s: registering i2c driver failed: %d", 468 __func__, ret); 469 else 470 tfp410_registered_driver.i2c = 1; 471 #endif 472 473 ret = platform_driver_register(&tfp410_platform_driver); 474 if (ret) 475 pr_err("%s: registering platform driver failed: %d", 476 __func__, ret); 477 else 478 tfp410_registered_driver.platform = 1; 479 480 if (tfp410_registered_driver.i2c || 481 tfp410_registered_driver.platform) 482 return 0; 483 484 return ret; 485 } 486 module_init(tfp410_module_init); 487 488 static void __exit tfp410_module_exit(void) 489 { 490 #if IS_ENABLED(CONFIG_I2C) 491 if (tfp410_registered_driver.i2c) 492 i2c_del_driver(&tfp410_i2c_driver); 493 #endif 494 if (tfp410_registered_driver.platform) 495 platform_driver_unregister(&tfp410_platform_driver); 496 } 497 module_exit(tfp410_module_exit); 498 499 MODULE_AUTHOR("Jyri Sarha <jsarha@ti.com>"); 500 MODULE_DESCRIPTION("TI TFP410 DVI bridge driver"); 501 MODULE_LICENSE("GPL"); 502