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