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