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         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 const struct drm_bridge_funcs tfp410_bridge_funcs = {
 210         .attach         = tfp410_attach,
 211         .detach         = tfp410_detach,
 212         .enable         = tfp410_enable,
 213         .disable        = tfp410_disable,
 214         .mode_valid     = tfp410_mode_valid,
 215 };
 216
 217 static const struct drm_bridge_timings tfp410_default_timings = {
 218         .input_bus_flags = DRM_BUS_FLAG_PIXDATA_SAMPLE_POSEDGE
 219                          | DRM_BUS_FLAG_DE_HIGH,
 220         .setup_time_ps = 1200,
 221         .hold_time_ps = 1300,
 222 };
 223
 224 static int tfp410_parse_timings(struct tfp410 *dvi, bool i2c)
 225 {
 226         struct drm_bridge_timings *timings = &dvi->timings;
 227         struct device_node *ep;
 228         u32 pclk_sample = 0;
 229         u32 bus_width = 24;
 230         u32 deskew = 0;
 231
 232         /* Start with defaults. */
 233         *timings = tfp410_default_timings;
 234
 235         if (i2c)
 236                 /*
 237                  * In I2C mode timings are configured through the I2C interface.
 238                  * As the driver doesn't support I2C configuration yet, we just
 239                  * go with the defaults (BSEL=1, DSEL=1, DKEN=0, EDGE=1).
 240                  */
 241                 return 0;
 242
 243         /*
 244          * In non-I2C mode, timings are configured through the BSEL, DSEL, DKEN
 245          * and EDGE pins. They are specified in DT through endpoint properties
 246          * and vendor-specific properties.
 247          */
 248         ep = of_graph_get_endpoint_by_regs(dvi->dev->of_node, 0, 0);
 249         if (!ep)
 250                 return -EINVAL;
 251
 252         /* Get the sampling edge from the endpoint. */
 253         of_property_read_u32(ep, "pclk-sample", &pclk_sample);
 254         of_property_read_u32(ep, "bus-width", &bus_width);
 255         of_node_put(ep);
 256
 257         timings->input_bus_flags = DRM_BUS_FLAG_DE_HIGH;
 258
 259         switch (pclk_sample) {
 260         case 0:
 261                 timings->input_bus_flags |= DRM_BUS_FLAG_PIXDATA_SAMPLE_NEGEDGE
 262                                          |  DRM_BUS_FLAG_SYNC_SAMPLE_NEGEDGE;
 263                 break;
 264         case 1:
 265                 timings->input_bus_flags |= DRM_BUS_FLAG_PIXDATA_SAMPLE_POSEDGE
 266                                          |  DRM_BUS_FLAG_SYNC_SAMPLE_POSEDGE;
 267                 break;
 268         default:
 269                 return -EINVAL;
 270         }
 271
 272         switch (bus_width) {
 273         case 12:
 274                 dvi->bus_format = MEDIA_BUS_FMT_RGB888_2X12_LE;
 275                 break;
 276         case 24:
 277                 dvi->bus_format = MEDIA_BUS_FMT_RGB888_1X24;
 278                 break;
 279         default:
 280                 return -EINVAL;
 281         }
 282
 283         /* Get the setup and hold time from vendor-specific properties. */
 284         of_property_read_u32(dvi->dev->of_node, "ti,deskew", &deskew);
 285         if (deskew > 7)
 286                 return -EINVAL;
 287
 288         timings->setup_time_ps = 1200 - 350 * ((s32)deskew - 4);
 289         timings->hold_time_ps = max(0, 1300 + 350 * ((s32)deskew - 4));
 290
 291         return 0;
 292 }
 293
 294 static int tfp410_init(struct device *dev, bool i2c)
 295 {
 296         struct device_node *node;
 297         struct tfp410 *dvi;
 298         int ret;
 299
 300         if (!dev->of_node) {
 301                 dev_err(dev, "device-tree data is missing\n");
 302                 return -ENXIO;
 303         }
 304
 305         dvi = devm_kzalloc(dev, sizeof(*dvi), GFP_KERNEL);
 306         if (!dvi)
 307                 return -ENOMEM;
 308
 309         dvi->dev = dev;
 310         dev_set_drvdata(dev, dvi);
 311
 312         dvi->bridge.funcs = &tfp410_bridge_funcs;
 313         dvi->bridge.of_node = dev->of_node;
 314         dvi->bridge.timings = &dvi->timings;
 315         dvi->bridge.type = DRM_MODE_CONNECTOR_DVID;
 316
 317         ret = tfp410_parse_timings(dvi, i2c);
 318         if (ret)
 319                 return ret;
 320
 321         /* Get the next bridge, connected to port@1. */
 322         node = of_graph_get_remote_node(dev->of_node, 1, -1);
 323         if (!node)
 324                 return -ENODEV;
 325
 326         dvi->next_bridge = of_drm_find_bridge(node);
 327         of_node_put(node);
 328
 329         if (!dvi->next_bridge)
 330                 return -EPROBE_DEFER;
 331
 332         /* Get the powerdown GPIO. */
 333         dvi->powerdown = devm_gpiod_get_optional(dev, "powerdown",
 334                                                  GPIOD_OUT_HIGH);
 335         if (IS_ERR(dvi->powerdown)) {
 336                 dev_err(dev, "failed to parse powerdown gpio\n");
 337                 return PTR_ERR(dvi->powerdown);
 338         }
 339
 340         /*  Register the DRM bridge. */
 341         drm_bridge_add(&dvi->bridge);
 342
 343         return 0;
 344 }
 345
 346 static void tfp410_fini(struct device *dev)
 347 {
 348         struct tfp410 *dvi = dev_get_drvdata(dev);
 349
 350         drm_bridge_remove(&dvi->bridge);
 351 }
 352
 353 static int tfp410_probe(struct platform_device *pdev)
 354 {
 355         return tfp410_init(&pdev->dev, false);
 356 }
 357
 358 static int tfp410_remove(struct platform_device *pdev)
 359 {
 360         tfp410_fini(&pdev->dev);
 361
 362         return 0;
 363 }
 364
 365 static const struct of_device_id tfp410_match[] = {
 366         { .compatible = "ti,tfp410" },
 367         {},
 368 };
 369 MODULE_DEVICE_TABLE(of, tfp410_match);
 370
 371 static struct platform_driver tfp410_platform_driver = {
 372         .probe  = tfp410_probe,
 373         .remove = tfp410_remove,
 374         .driver = {
 375                 .name           = "tfp410-bridge",
 376                 .of_match_table = tfp410_match,
 377         },
 378 };
 379
 380 #if IS_ENABLED(CONFIG_I2C)
 381 /* There is currently no i2c functionality. */
 382 static int tfp410_i2c_probe(struct i2c_client *client,
 383                             const struct i2c_device_id *id)
 384 {
 385         int reg;
 386
 387         if (!client->dev.of_node ||
 388             of_property_read_u32(client->dev.of_node, "reg", &reg)) {
 389                 dev_err(&client->dev,
 390                         "Can't get i2c reg property from device-tree\n");
 391                 return -ENXIO;
 392         }
 393
 394         return tfp410_init(&client->dev, true);
 395 }
 396
 397 static void tfp410_i2c_remove(struct i2c_client *client)
 398 {
 399         tfp410_fini(&client->dev);
 400 }
 401
 402 static const struct i2c_device_id tfp410_i2c_ids[] = {
 403         { "tfp410", 0 },
 404         { }
 405 };
 406 MODULE_DEVICE_TABLE(i2c, tfp410_i2c_ids);
 407
 408 static struct i2c_driver tfp410_i2c_driver = {
 409         .driver = {
 410                 .name   = "tfp410",
 411                 .of_match_table = of_match_ptr(tfp410_match),
 412         },
 413         .id_table       = tfp410_i2c_ids,
 414         .probe          = tfp410_i2c_probe,
 415         .remove         = tfp410_i2c_remove,
 416 };
 417 #endif /* IS_ENABLED(CONFIG_I2C) */
 418
 419 static struct {
 420         uint i2c:1;
 421         uint platform:1;
 422 }  tfp410_registered_driver;
 423
 424 static int __init tfp410_module_init(void)
 425 {
 426         int ret;
 427
 428 #if IS_ENABLED(CONFIG_I2C)
 429         ret = i2c_add_driver(&tfp410_i2c_driver);
 430         if (ret)
 431                 pr_err("%s: registering i2c driver failed: %d",
 432                        __func__, ret);
 433         else
 434                 tfp410_registered_driver.i2c = 1;
 435 #endif
 436
 437         ret = platform_driver_register(&tfp410_platform_driver);
 438         if (ret)
 439                 pr_err("%s: registering platform driver failed: %d",
 440                        __func__, ret);
 441         else
 442                 tfp410_registered_driver.platform = 1;
 443
 444         if (tfp410_registered_driver.i2c ||
 445             tfp410_registered_driver.platform)
 446                 return 0;
 447
 448         return ret;
 449 }
 450 module_init(tfp410_module_init);
 451
 452 static void __exit tfp410_module_exit(void)
 453 {
 454 #if IS_ENABLED(CONFIG_I2C)
 455         if (tfp410_registered_driver.i2c)
 456                 i2c_del_driver(&tfp410_i2c_driver);
 457 #endif
 458         if (tfp410_registered_driver.platform)
 459                 platform_driver_unregister(&tfp410_platform_driver);
 460 }
 461 module_exit(tfp410_module_exit);
 462
 463 MODULE_AUTHOR("Jyri Sarha <[email protected]>");
 464 MODULE_DESCRIPTION("TI TFP410 DVI bridge driver");
 465 MODULE_LICENSE("GPL");