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 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 (!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", ®)) { 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"); 506