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/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         struct edid *edid;
  54         int ret;
  55
  56         if (dvi->next_bridge->ops & DRM_BRIDGE_OP_EDID) {
  57                 edid = drm_bridge_get_edid(dvi->next_bridge, connector);
  58                 if (!edid)
  59                         DRM_INFO("EDID read failed. Fallback to standard modes\n");
  60         } else {
  61                 edid = NULL;
  62         }
  63
  64         if (!edid) {
  65                 /*
  66                  * No EDID, fallback on the XGA standard modes and prefer a mode
  67                  * pretty much anything can handle.
  68                  */
  69                 ret = drm_add_modes_noedid(connector, 1920, 1200);
  70                 drm_set_preferred_mode(connector, 1024, 768);
  71                 return ret;
  72         }
  73
  74         drm_connector_update_edid_property(connector, edid);
  75
  76         ret = drm_add_edid_modes(connector, edid);
  77
  78         kfree(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 (!bridge->encoder) {
 137                 dev_err(dvi->dev, "Missing encoder\n");
 138                 return -ENODEV;
 139         }
 140
 141         if (dvi->next_bridge->ops & DRM_BRIDGE_OP_DETECT)
 142                 dvi->connector.polled = DRM_CONNECTOR_POLL_HPD;
 143         else
 144                 dvi->connector.polled = DRM_CONNECTOR_POLL_CONNECT | DRM_CONNECTOR_POLL_DISCONNECT;
 145
 146         if (dvi->next_bridge->ops & DRM_BRIDGE_OP_HPD) {
 147                 INIT_DELAYED_WORK(&dvi->hpd_work, tfp410_hpd_work_func);
 148                 drm_bridge_hpd_enable(dvi->next_bridge, tfp410_hpd_callback,
 149                                       dvi);
 150         }
 151
 152         drm_connector_helper_add(&dvi->connector,
 153                                  &tfp410_con_helper_funcs);
 154         ret = drm_connector_init_with_ddc(bridge->dev, &dvi->connector,
 155                                           &tfp410_con_funcs,
 156                                           dvi->next_bridge->type,
 157                                           dvi->next_bridge->ddc);
 158         if (ret) {
 159                 dev_err(dvi->dev, "drm_connector_init_with_ddc() failed: %d\n",
 160                         ret);
 161                 return ret;
 162         }
 163
 164         drm_display_info_set_bus_formats(&dvi->connector.display_info,
 165                                          &dvi->bus_format, 1);
 166
 167         drm_connector_attach_encoder(&dvi->connector, bridge->encoder);
 168
 169         return 0;
 170 }
 171
 172 static void tfp410_detach(struct drm_bridge *bridge)
 173 {
 174         struct tfp410 *dvi = drm_bridge_to_tfp410(bridge);
 175
 176         if (dvi->connector.dev && dvi->next_bridge->ops & DRM_BRIDGE_OP_HPD) {
 177                 drm_bridge_hpd_disable(dvi->next_bridge);
 178                 cancel_delayed_work_sync(&dvi->hpd_work);
 179         }
 180 }
 181
 182 static void tfp410_enable(struct drm_bridge *bridge)
 183 {
 184         struct tfp410 *dvi = drm_bridge_to_tfp410(bridge);
 185
 186         gpiod_set_value_cansleep(dvi->powerdown, 0);
 187 }
 188
 189 static void tfp410_disable(struct drm_bridge *bridge)
 190 {
 191         struct tfp410 *dvi = drm_bridge_to_tfp410(bridge);
 192
 193         gpiod_set_value_cansleep(dvi->powerdown, 1);
 194 }
 195
 196 static enum drm_mode_status tfp410_mode_valid(struct drm_bridge *bridge,
 197                                               const struct drm_display_info *info,
 198                                               const struct drm_display_mode *mode)
 199 {
 200         if (mode->clock < 25000)
 201                 return MODE_CLOCK_LOW;
 202
 203         if (mode->clock > 165000)
 204                 return MODE_CLOCK_HIGH;
 205
 206         return MODE_OK;
 207 }
 208
 209 static u32 *tfp410_get_input_bus_fmts(struct drm_bridge *bridge,
 210                                       struct drm_bridge_state *bridge_state,
 211                                       struct drm_crtc_state *crtc_state,
 212                                       struct drm_connector_state *conn_state,
 213                                       u32 output_fmt,
 214                                       unsigned int *num_input_fmts)
 215 {
 216         struct tfp410 *dvi = drm_bridge_to_tfp410(bridge);
 217         u32 *input_fmts;
 218
 219         *num_input_fmts = 0;
 220
 221         input_fmts = kzalloc(sizeof(*input_fmts), GFP_KERNEL);
 222         if (!input_fmts)
 223                 return NULL;
 224
 225         *num_input_fmts = 1;
 226         input_fmts[0] = dvi->bus_format;
 227
 228         return input_fmts;
 229 }
 230
 231 static int tfp410_atomic_check(struct drm_bridge *bridge,
 232                                struct drm_bridge_state *bridge_state,
 233                                struct drm_crtc_state *crtc_state,
 234                                struct drm_connector_state *conn_state)
 235 {
 236         struct tfp410 *dvi = drm_bridge_to_tfp410(bridge);
 237
 238         /*
 239          * There might be flags negotiation supported in future.
 240          * Set the bus flags in atomic_check statically for now.
 241          */
 242         bridge_state->input_bus_cfg.flags = dvi->timings.input_bus_flags;
 243
 244         return 0;
 245 }
 246
 247 static const struct drm_bridge_funcs tfp410_bridge_funcs = {
 248         .attach         = tfp410_attach,
 249         .detach         = tfp410_detach,
 250         .enable         = tfp410_enable,
 251         .disable        = tfp410_disable,
 252         .mode_valid     = tfp410_mode_valid,
 253         .atomic_reset = drm_atomic_helper_bridge_reset,
 254         .atomic_duplicate_state = drm_atomic_helper_bridge_duplicate_state,
 255         .atomic_destroy_state = drm_atomic_helper_bridge_destroy_state,
 256         .atomic_get_input_bus_fmts = tfp410_get_input_bus_fmts,
 257         .atomic_check = tfp410_atomic_check,
 258 };
 259
 260 static const struct drm_bridge_timings tfp410_default_timings = {
 261         .input_bus_flags = DRM_BUS_FLAG_PIXDATA_SAMPLE_POSEDGE
 262                          | DRM_BUS_FLAG_DE_HIGH,
 263         .setup_time_ps = 1200,
 264         .hold_time_ps = 1300,
 265 };
 266
 267 static int tfp410_parse_timings(struct tfp410 *dvi, bool i2c)
 268 {
 269         struct drm_bridge_timings *timings = &dvi->timings;
 270         struct device_node *ep;
 271         u32 pclk_sample = 0;
 272         u32 bus_width = 24;
 273         u32 deskew = 0;
 274
 275         /* Start with defaults. */
 276         *timings = tfp410_default_timings;
 277
 278         if (i2c)
 279                 /*
 280                  * In I2C mode timings are configured through the I2C interface.
 281                  * As the driver doesn't support I2C configuration yet, we just
 282                  * go with the defaults (BSEL=1, DSEL=1, DKEN=0, EDGE=1).
 283                  */
 284                 return 0;
 285
 286         /*
 287          * In non-I2C mode, timings are configured through the BSEL, DSEL, DKEN
 288          * and EDGE pins. They are specified in DT through endpoint properties
 289          * and vendor-specific properties.
 290          */
 291         ep = of_graph_get_endpoint_by_regs(dvi->dev->of_node, 0, 0);
 292         if (!ep)
 293                 return -EINVAL;
 294
 295         /* Get the sampling edge from the endpoint. */
 296         of_property_read_u32(ep, "pclk-sample", &pclk_sample);
 297         of_property_read_u32(ep, "bus-width", &bus_width);
 298         of_node_put(ep);
 299
 300         timings->input_bus_flags = DRM_BUS_FLAG_DE_HIGH;
 301
 302         switch (pclk_sample) {
 303         case 0:
 304                 timings->input_bus_flags |= DRM_BUS_FLAG_PIXDATA_SAMPLE_NEGEDGE
 305                                          |  DRM_BUS_FLAG_SYNC_SAMPLE_NEGEDGE;
 306                 break;
 307         case 1:
 308                 timings->input_bus_flags |= DRM_BUS_FLAG_PIXDATA_SAMPLE_POSEDGE
 309                                          |  DRM_BUS_FLAG_SYNC_SAMPLE_POSEDGE;
 310                 break;
 311         default:
 312                 return -EINVAL;
 313         }
 314
 315         switch (bus_width) {
 316         case 12:
 317                 dvi->bus_format = MEDIA_BUS_FMT_RGB888_2X12_LE;
 318                 break;
 319         case 24:
 320                 dvi->bus_format = MEDIA_BUS_FMT_RGB888_1X24;
 321                 break;
 322         default:
 323                 return -EINVAL;
 324         }
 325
 326         /* Get the setup and hold time from vendor-specific properties. */
 327         of_property_read_u32(dvi->dev->of_node, "ti,deskew", &deskew);
 328         if (deskew > 7)
 329                 return -EINVAL;
 330
 331         timings->setup_time_ps = 1200 - 350 * ((s32)deskew - 4);
 332         timings->hold_time_ps = max(0, 1300 + 350 * ((s32)deskew - 4));
 333
 334         return 0;
 335 }
 336
 337 static int tfp410_init(struct device *dev, bool i2c)
 338 {
 339         struct device_node *node;
 340         struct tfp410 *dvi;
 341         int ret;
 342
 343         if (!dev->of_node) {
 344                 dev_err(dev, "device-tree data is missing\n");
 345                 return -ENXIO;
 346         }
 347
 348         dvi = devm_kzalloc(dev, sizeof(*dvi), GFP_KERNEL);
 349         if (!dvi)
 350                 return -ENOMEM;
 351
 352         dvi->dev = dev;
 353         dev_set_drvdata(dev, dvi);
 354
 355         dvi->bridge.funcs = &tfp410_bridge_funcs;
 356         dvi->bridge.of_node = dev->of_node;
 357         dvi->bridge.timings = &dvi->timings;
 358         dvi->bridge.type = DRM_MODE_CONNECTOR_DVID;
 359
 360         ret = tfp410_parse_timings(dvi, i2c);
 361         if (ret)
 362                 return ret;
 363
 364         /* Get the next bridge, connected to port@1. */
 365         node = of_graph_get_remote_node(dev->of_node, 1, -1);
 366         if (!node)
 367                 return -ENODEV;
 368
 369         dvi->next_bridge = of_drm_find_bridge(node);
 370         of_node_put(node);
 371
 372         if (!dvi->next_bridge)
 373                 return -EPROBE_DEFER;
 374
 375         /* Get the powerdown GPIO. */
 376         dvi->powerdown = devm_gpiod_get_optional(dev, "powerdown",
 377                                                  GPIOD_OUT_HIGH);
 378         if (IS_ERR(dvi->powerdown)) {
 379                 dev_err(dev, "failed to parse powerdown gpio\n");
 380                 return PTR_ERR(dvi->powerdown);
 381         }
 382
 383         /*  Register the DRM bridge. */
 384         drm_bridge_add(&dvi->bridge);
 385
 386         return 0;
 387 }
 388
 389 static void tfp410_fini(struct device *dev)
 390 {
 391         struct tfp410 *dvi = dev_get_drvdata(dev);
 392
 393         drm_bridge_remove(&dvi->bridge);
 394 }
 395
 396 static int tfp410_probe(struct platform_device *pdev)
 397 {
 398         return tfp410_init(&pdev->dev, false);
 399 }
 400
 401 static void tfp410_remove(struct platform_device *pdev)
 402 {
 403         tfp410_fini(&pdev->dev);
 404 }
 405
 406 static const struct of_device_id tfp410_match[] = {
 407         { .compatible = "ti,tfp410" },
 408         {},
 409 };
 410 MODULE_DEVICE_TABLE(of, tfp410_match);
 411
 412 static struct platform_driver tfp410_platform_driver = {
 413         .probe  = tfp410_probe,
 414         .remove_new = tfp410_remove,
 415         .driver = {
 416                 .name           = "tfp410-bridge",
 417                 .of_match_table = tfp410_match,
 418         },
 419 };
 420
 421 #if IS_ENABLED(CONFIG_I2C)
 422 /* There is currently no i2c functionality. */
 423 static int tfp410_i2c_probe(struct i2c_client *client)
 424 {
 425         int reg;
 426
 427         if (!client->dev.of_node ||
 428             of_property_read_u32(client->dev.of_node, "reg", &reg)) {
 429                 dev_err(&client->dev,
 430                         "Can't get i2c reg property from device-tree\n");
 431                 return -ENXIO;
 432         }
 433
 434         return tfp410_init(&client->dev, true);
 435 }
 436
 437 static void tfp410_i2c_remove(struct i2c_client *client)
 438 {
 439         tfp410_fini(&client->dev);
 440 }
 441
 442 static const struct i2c_device_id tfp410_i2c_ids[] = {
 443         { "tfp410", 0 },
 444         { }
 445 };
 446 MODULE_DEVICE_TABLE(i2c, tfp410_i2c_ids);
 447
 448 static struct i2c_driver tfp410_i2c_driver = {
 449         .driver = {
 450                 .name   = "tfp410",
 451                 .of_match_table = tfp410_match,
 452         },
 453         .id_table       = tfp410_i2c_ids,
 454         .probe          = tfp410_i2c_probe,
 455         .remove         = tfp410_i2c_remove,
 456 };
 457 #endif /* IS_ENABLED(CONFIG_I2C) */
 458
 459 static struct {
 460         uint i2c:1;
 461         uint platform:1;
 462 }  tfp410_registered_driver;
 463
 464 static int __init tfp410_module_init(void)
 465 {
 466         int ret;
 467
 468 #if IS_ENABLED(CONFIG_I2C)
 469         ret = i2c_add_driver(&tfp410_i2c_driver);
 470         if (ret)
 471                 pr_err("%s: registering i2c driver failed: %d",
 472                        __func__, ret);
 473         else
 474                 tfp410_registered_driver.i2c = 1;
 475 #endif
 476
 477         ret = platform_driver_register(&tfp410_platform_driver);
 478         if (ret)
 479                 pr_err("%s: registering platform driver failed: %d",
 480                        __func__, ret);
 481         else
 482                 tfp410_registered_driver.platform = 1;
 483
 484         if (tfp410_registered_driver.i2c ||
 485             tfp410_registered_driver.platform)
 486                 return 0;
 487
 488         return ret;
 489 }
 490 module_init(tfp410_module_init);
 491
 492 static void __exit tfp410_module_exit(void)
 493 {
 494 #if IS_ENABLED(CONFIG_I2C)
 495         if (tfp410_registered_driver.i2c)
 496                 i2c_del_driver(&tfp410_i2c_driver);
 497 #endif
 498         if (tfp410_registered_driver.platform)
 499                 platform_driver_unregister(&tfp410_platform_driver);
 500 }
 501 module_exit(tfp410_module_exit);
 502
 503 MODULE_AUTHOR("Jyri Sarha <jsarha@ti.com>");
 504 MODULE_DESCRIPTION("TI TFP410 DVI bridge driver");
 505 MODULE_LICENSE("GPL");