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/gpio/consumer.h>
   8 #include <linux/i2c.h>
   9 #include <linux/media-bus-format.h>
  10 #include <linux/module.h>
  11 #include <linux/of_graph.h>
  12 #include <linux/platform_device.h>
  13 #include <linux/workqueue.h>
  14
  15 #include <drm/drm_atomic_helper.h>
  16 #include <drm/drm_bridge.h>
  17 #include <drm/drm_crtc.h>
  18 #include <drm/drm_edid.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
  28         u32                     bus_format;
  29         struct delayed_work     hpd_work;
  30         struct gpio_desc        *powerdown;
  31
  32         struct drm_bridge_timings timings;
  33         struct drm_bridge       *next_bridge;
  34
  35         struct device *dev;
  36 };
  37
  38 static inline struct tfp410 *
  39 drm_bridge_to_tfp410(struct drm_bridge *bridge)
  40 {
  41         return container_of(bridge, struct tfp410, bridge);
  42 }
  43
  44 static inline struct tfp410 *
  45 drm_connector_to_tfp410(struct drm_connector *connector)
  46 {
  47         return container_of(connector, struct tfp410, connector);
  48 }
  49
  50 static int tfp410_get_modes(struct drm_connector *connector)
  51 {
  52         struct tfp410 *dvi = drm_connector_to_tfp410(connector);
  53         const struct drm_edid *drm_edid;
  54         int ret;
  55
  56         if (dvi->next_bridge->ops & DRM_BRIDGE_OP_EDID) {
  57                 drm_edid = drm_bridge_edid_read(dvi->next_bridge, connector);
  58                 if (!drm_edid)
  59                         DRM_INFO("EDID read failed. Fallback to standard modes\n");
  60         } else {
  61                 drm_edid = NULL;
  62         }
  63
  64         drm_edid_connector_update(connector, drm_edid);
  65
  66         if (!drm_edid) {
  67                 /*
  68                  * No EDID, fallback on the XGA standard modes and prefer a mode
  69                  * pretty much anything can handle.
  70                  */
  71                 ret = drm_add_modes_noedid(connector, 1920, 1200);
  72                 drm_set_preferred_mode(connector, 1024, 768);
  73                 return ret;
  74         }
  75
  76         ret = drm_edid_connector_add_modes(connector);
  77
  78         drm_edid_free(drm_edid);
  79
  80         return ret;
  81 }
  82
  83 static const struct drm_connector_helper_funcs tfp410_con_helper_funcs = {
  84         .get_modes      = tfp410_get_modes,
  85 };
  86
  87 static enum drm_connector_status
  88 tfp410_connector_detect(struct drm_connector *connector, bool force)
  89 {
  90         struct tfp410 *dvi = drm_connector_to_tfp410(connector);
  91
  92         return drm_bridge_detect(dvi->next_bridge);
  93 }
  94
  95 static const struct drm_connector_funcs tfp410_con_funcs = {
  96         .detect                 = tfp410_connector_detect,
  97         .fill_modes             = drm_helper_probe_single_connector_modes,
  98         .destroy                = drm_connector_cleanup,
  99         .reset                  = drm_atomic_helper_connector_reset,
 100         .atomic_duplicate_state = drm_atomic_helper_connector_duplicate_state,
 101         .atomic_destroy_state   = drm_atomic_helper_connector_destroy_state,
 102 };
 103
 104 static void tfp410_hpd_work_func(struct work_struct *work)
 105 {
 106         struct tfp410 *dvi;
 107
 108         dvi = container_of(work, struct tfp410, hpd_work.work);
 109
 110         if (dvi->bridge.dev)
 111                 drm_helper_hpd_irq_event(dvi->bridge.dev);
 112 }
 113
 114 static void tfp410_hpd_callback(void *arg, enum drm_connector_status status)
 115 {
 116         struct tfp410 *dvi = arg;
 117
 118         mod_delayed_work(system_wq, &dvi->hpd_work,
 119                          msecs_to_jiffies(HOTPLUG_DEBOUNCE_MS));
 120 }
 121
 122 static int tfp410_attach(struct drm_bridge *bridge,
 123                          enum drm_bridge_attach_flags flags)
 124 {
 125         struct tfp410 *dvi = drm_bridge_to_tfp410(bridge);
 126         int ret;
 127
 128         ret = drm_bridge_attach(bridge->encoder, dvi->next_bridge, bridge,
 129                                 DRM_BRIDGE_ATTACH_NO_CONNECTOR);
 130         if (ret < 0)
 131                 return ret;
 132
 133         if (flags & DRM_BRIDGE_ATTACH_NO_CONNECTOR)
 134                 return 0;
 135
 136         if (dvi->next_bridge->ops & DRM_BRIDGE_OP_DETECT)
 137                 dvi->connector.polled = DRM_CONNECTOR_POLL_HPD;
 138         else
 139                 dvi->connector.polled = DRM_CONNECTOR_POLL_CONNECT | DRM_CONNECTOR_POLL_DISCONNECT;
 140
 141         if (dvi->next_bridge->ops & DRM_BRIDGE_OP_HPD) {
 142                 INIT_DELAYED_WORK(&dvi->hpd_work, tfp410_hpd_work_func);
 143                 drm_bridge_hpd_enable(dvi->next_bridge, tfp410_hpd_callback,
 144                                       dvi);
 145         }
 146
 147         drm_connector_helper_add(&dvi->connector,
 148                                  &tfp410_con_helper_funcs);
 149         ret = drm_connector_init_with_ddc(bridge->dev, &dvi->connector,
 150                                           &tfp410_con_funcs,
 151                                           dvi->next_bridge->type,
 152                                           dvi->next_bridge->ddc);
 153         if (ret) {
 154                 dev_err(dvi->dev, "drm_connector_init_with_ddc() failed: %d\n",
 155                         ret);
 156                 return ret;
 157         }
 158
 159         drm_display_info_set_bus_formats(&dvi->connector.display_info,
 160                                          &dvi->bus_format, 1);
 161
 162         drm_connector_attach_encoder(&dvi->connector, bridge->encoder);
 163
 164         return 0;
 165 }
 166
 167 static void tfp410_detach(struct drm_bridge *bridge)
 168 {
 169         struct tfp410 *dvi = drm_bridge_to_tfp410(bridge);
 170
 171         if (dvi->connector.dev && dvi->next_bridge->ops & DRM_BRIDGE_OP_HPD) {
 172                 drm_bridge_hpd_disable(dvi->next_bridge);
 173                 cancel_delayed_work_sync(&dvi->hpd_work);
 174         }
 175 }
 176
 177 static void tfp410_enable(struct drm_bridge *bridge)
 178 {
 179         struct tfp410 *dvi = drm_bridge_to_tfp410(bridge);
 180
 181         gpiod_set_value_cansleep(dvi->powerdown, 0);
 182 }
 183
 184 static void tfp410_disable(struct drm_bridge *bridge)
 185 {
 186         struct tfp410 *dvi = drm_bridge_to_tfp410(bridge);
 187
 188         gpiod_set_value_cansleep(dvi->powerdown, 1);
 189 }
 190
 191 static enum drm_mode_status tfp410_mode_valid(struct drm_bridge *bridge,
 192                                               const struct drm_display_info *info,
 193                                               const struct drm_display_mode *mode)
 194 {
 195         if (mode->clock < 25000)
 196                 return MODE_CLOCK_LOW;
 197
 198         if (mode->clock > 165000)
 199                 return MODE_CLOCK_HIGH;
 200
 201         return MODE_OK;
 202 }
 203
 204 static u32 *tfp410_get_input_bus_fmts(struct drm_bridge *bridge,
 205                                       struct drm_bridge_state *bridge_state,
 206                                       struct drm_crtc_state *crtc_state,
 207                                       struct drm_connector_state *conn_state,
 208                                       u32 output_fmt,
 209                                       unsigned int *num_input_fmts)
 210 {
 211         struct tfp410 *dvi = drm_bridge_to_tfp410(bridge);
 212         u32 *input_fmts;
 213
 214         *num_input_fmts = 0;
 215
 216         input_fmts = kzalloc(sizeof(*input_fmts), GFP_KERNEL);
 217         if (!input_fmts)
 218                 return NULL;
 219
 220         *num_input_fmts = 1;
 221         input_fmts[0] = dvi->bus_format;
 222
 223         return input_fmts;
 224 }
 225
 226 static int tfp410_atomic_check(struct drm_bridge *bridge,
 227                                struct drm_bridge_state *bridge_state,
 228                                struct drm_crtc_state *crtc_state,
 229                                struct drm_connector_state *conn_state)
 230 {
 231         struct tfp410 *dvi = drm_bridge_to_tfp410(bridge);
 232
 233         /*
 234          * There might be flags negotiation supported in future.
 235          * Set the bus flags in atomic_check statically for now.
 236          */
 237         bridge_state->input_bus_cfg.flags = dvi->timings.input_bus_flags;
 238
 239         return 0;
 240 }
 241
 242 static const struct drm_bridge_funcs tfp410_bridge_funcs = {
 243         .attach         = tfp410_attach,
 244         .detach         = tfp410_detach,
 245         .enable         = tfp410_enable,
 246         .disable        = tfp410_disable,
 247         .mode_valid     = tfp410_mode_valid,
 248         .atomic_reset = drm_atomic_helper_bridge_reset,
 249         .atomic_duplicate_state = drm_atomic_helper_bridge_duplicate_state,
 250         .atomic_destroy_state = drm_atomic_helper_bridge_destroy_state,
 251         .atomic_get_input_bus_fmts = tfp410_get_input_bus_fmts,
 252         .atomic_check = tfp410_atomic_check,
 253 };
 254
 255 static const struct drm_bridge_timings tfp410_default_timings = {
 256         .input_bus_flags = DRM_BUS_FLAG_PIXDATA_SAMPLE_POSEDGE
 257                          | DRM_BUS_FLAG_DE_HIGH,
 258         .setup_time_ps = 1200,
 259         .hold_time_ps = 1300,
 260 };
 261
 262 static int tfp410_parse_timings(struct tfp410 *dvi, bool i2c)
 263 {
 264         struct drm_bridge_timings *timings = &dvi->timings;
 265         struct device_node *ep;
 266         u32 pclk_sample = 0;
 267         u32 bus_width = 24;
 268         u32 deskew = 0;
 269
 270         /* Start with defaults. */
 271         *timings = tfp410_default_timings;
 272
 273         if (i2c)
 274                 /*
 275                  * In I2C mode timings are configured through the I2C interface.
 276                  * As the driver doesn't support I2C configuration yet, we just
 277                  * go with the defaults (BSEL=1, DSEL=1, DKEN=0, EDGE=1).
 278                  */
 279                 return 0;
 280
 281         /*
 282          * In non-I2C mode, timings are configured through the BSEL, DSEL, DKEN
 283          * and EDGE pins. They are specified in DT through endpoint properties
 284          * and vendor-specific properties.
 285          */
 286         ep = of_graph_get_endpoint_by_regs(dvi->dev->of_node, 0, 0);
 287         if (!ep)
 288                 return -EINVAL;
 289
 290         /* Get the sampling edge from the endpoint. */
 291         of_property_read_u32(ep, "pclk-sample", &pclk_sample);
 292         of_property_read_u32(ep, "bus-width", &bus_width);
 293         of_node_put(ep);
 294
 295         timings->input_bus_flags = DRM_BUS_FLAG_DE_HIGH;
 296
 297         switch (pclk_sample) {
 298         case 0:
 299                 timings->input_bus_flags |= DRM_BUS_FLAG_PIXDATA_SAMPLE_NEGEDGE
 300                                          |  DRM_BUS_FLAG_SYNC_SAMPLE_NEGEDGE;
 301                 break;
 302         case 1:
 303                 timings->input_bus_flags |= DRM_BUS_FLAG_PIXDATA_SAMPLE_POSEDGE
 304                                          |  DRM_BUS_FLAG_SYNC_SAMPLE_POSEDGE;
 305                 break;
 306         default:
 307                 return -EINVAL;
 308         }
 309
 310         switch (bus_width) {
 311         case 12:
 312                 dvi->bus_format = MEDIA_BUS_FMT_RGB888_2X12_LE;
 313                 break;
 314         case 24:
 315                 dvi->bus_format = MEDIA_BUS_FMT_RGB888_1X24;
 316                 break;
 317         default:
 318                 return -EINVAL;
 319         }
 320
 321         /* Get the setup and hold time from vendor-specific properties. */
 322         of_property_read_u32(dvi->dev->of_node, "ti,deskew", &deskew);
 323         if (deskew > 7)
 324                 return -EINVAL;
 325
 326         timings->setup_time_ps = 1200 - 350 * ((s32)deskew - 4);
 327         timings->hold_time_ps = max(0, 1300 + 350 * ((s32)deskew - 4));
 328
 329         return 0;
 330 }
 331
 332 static int tfp410_init(struct device *dev, bool i2c)
 333 {
 334         struct device_node *node;
 335         struct tfp410 *dvi;
 336         int ret;
 337
 338         if (!dev->of_node) {
 339                 dev_err(dev, "device-tree data is missing\n");
 340                 return -ENXIO;
 341         }
 342
 343         dvi = devm_kzalloc(dev, sizeof(*dvi), GFP_KERNEL);
 344         if (!dvi)
 345                 return -ENOMEM;
 346
 347         dvi->dev = dev;
 348         dev_set_drvdata(dev, dvi);
 349
 350         dvi->bridge.funcs = &tfp410_bridge_funcs;
 351         dvi->bridge.of_node = dev->of_node;
 352         dvi->bridge.timings = &dvi->timings;
 353         dvi->bridge.type = DRM_MODE_CONNECTOR_DVID;
 354
 355         ret = tfp410_parse_timings(dvi, i2c);
 356         if (ret)
 357                 return ret;
 358
 359         /* Get the next bridge, connected to port@1. */
 360         node = of_graph_get_remote_node(dev->of_node, 1, -1);
 361         if (!node)
 362                 return -ENODEV;
 363
 364         dvi->next_bridge = of_drm_find_bridge(node);
 365         of_node_put(node);
 366
 367         if (!dvi->next_bridge)
 368                 return -EPROBE_DEFER;
 369
 370         /* Get the powerdown GPIO. */
 371         dvi->powerdown = devm_gpiod_get_optional(dev, "powerdown",
 372                                                  GPIOD_OUT_HIGH);
 373         if (IS_ERR(dvi->powerdown)) {
 374                 dev_err(dev, "failed to parse powerdown gpio\n");
 375                 return PTR_ERR(dvi->powerdown);
 376         }
 377
 378         /*  Register the DRM bridge. */
 379         drm_bridge_add(&dvi->bridge);
 380
 381         return 0;
 382 }
 383
 384 static void tfp410_fini(struct device *dev)
 385 {
 386         struct tfp410 *dvi = dev_get_drvdata(dev);
 387
 388         drm_bridge_remove(&dvi->bridge);
 389 }
 390
 391 static int tfp410_probe(struct platform_device *pdev)
 392 {
 393         return tfp410_init(&pdev->dev, false);
 394 }
 395
 396 static void tfp410_remove(struct platform_device *pdev)
 397 {
 398         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 {
 420         int reg;
 421
 422         if (!client->dev.of_node ||
 423             of_property_read_u32(client->dev.of_node, "reg", &reg)) {
 424                 dev_err(&client->dev,
 425                         "Can't get i2c reg property from device-tree\n");
 426                 return -ENXIO;
 427         }
 428
 429         return tfp410_init(&client->dev, true);
 430 }
 431
 432 static void tfp410_i2c_remove(struct i2c_client *client)
 433 {
 434         tfp410_fini(&client->dev);
 435 }
 436
 437 static const struct i2c_device_id tfp410_i2c_ids[] = {
 438         { "tfp410" },
 439         { }
 440 };
 441 MODULE_DEVICE_TABLE(i2c, tfp410_i2c_ids);
 442
 443 static struct i2c_driver tfp410_i2c_driver = {
 444         .driver = {
 445                 .name   = "tfp410",
 446                 .of_match_table = tfp410_match,
 447         },
 448         .id_table       = tfp410_i2c_ids,
 449         .probe          = tfp410_i2c_probe,
 450         .remove         = tfp410_i2c_remove,
 451 };
 452 #endif /* IS_ENABLED(CONFIG_I2C) */
 453
 454 static struct {
 455         uint i2c:1;
 456         uint platform:1;
 457 }  tfp410_registered_driver;
 458
 459 static int __init tfp410_module_init(void)
 460 {
 461         int ret;
 462
 463 #if IS_ENABLED(CONFIG_I2C)
 464         ret = i2c_add_driver(&tfp410_i2c_driver);
 465         if (ret)
 466                 pr_err("%s: registering i2c driver failed: %d",
 467                        __func__, ret);
 468         else
 469                 tfp410_registered_driver.i2c = 1;
 470 #endif
 471
 472         ret = platform_driver_register(&tfp410_platform_driver);
 473         if (ret)
 474                 pr_err("%s: registering platform driver failed: %d",
 475                        __func__, ret);
 476         else
 477                 tfp410_registered_driver.platform = 1;
 478
 479         if (tfp410_registered_driver.i2c ||
 480             tfp410_registered_driver.platform)
 481                 return 0;
 482
 483         return ret;
 484 }
 485 module_init(tfp410_module_init);
 486
 487 static void __exit tfp410_module_exit(void)
 488 {
 489 #if IS_ENABLED(CONFIG_I2C)
 490         if (tfp410_registered_driver.i2c)
 491                 i2c_del_driver(&tfp410_i2c_driver);
 492 #endif
 493         if (tfp410_registered_driver.platform)
 494                 platform_driver_unregister(&tfp410_platform_driver);
 495 }
 496 module_exit(tfp410_module_exit);
 497
 498 MODULE_AUTHOR("Jyri Sarha <[email protected]>");
 499 MODULE_DESCRIPTION("TI TFP410 DVI bridge driver");
 500 MODULE_LICENSE("GPL");