drivers/gpu/drm/bridge/ti-tfp410.c

   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", &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");