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 struct drm_encoder *encoder, 124 enum drm_bridge_attach_flags flags) 125 { 126 struct tfp410 *dvi = drm_bridge_to_tfp410(bridge); 127 int ret; 128 129 ret = drm_bridge_attach(encoder, dvi->next_bridge, bridge, 130 DRM_BRIDGE_ATTACH_NO_CONNECTOR); 131 if (ret < 0) 132 return ret; 133 134 if (flags & DRM_BRIDGE_ATTACH_NO_CONNECTOR) 135 return 0; 136 137 if (dvi->next_bridge->ops & DRM_BRIDGE_OP_DETECT) 138 dvi->connector.polled = DRM_CONNECTOR_POLL_HPD; 139 else 140 dvi->connector.polled = DRM_CONNECTOR_POLL_CONNECT | DRM_CONNECTOR_POLL_DISCONNECT; 141 142 if (dvi->next_bridge->ops & DRM_BRIDGE_OP_HPD) { 143 INIT_DELAYED_WORK(&dvi->hpd_work, tfp410_hpd_work_func); 144 drm_bridge_hpd_enable(dvi->next_bridge, tfp410_hpd_callback, 145 dvi); 146 } 147 148 drm_connector_helper_add(&dvi->connector, 149 &tfp410_con_helper_funcs); 150 ret = drm_connector_init_with_ddc(bridge->dev, &dvi->connector, 151 &tfp410_con_funcs, 152 dvi->next_bridge->type, 153 dvi->next_bridge->ddc); 154 if (ret) { 155 dev_err(dvi->dev, "drm_connector_init_with_ddc() failed: %d\n", 156 ret); 157 return ret; 158 } 159 160 drm_display_info_set_bus_formats(&dvi->connector.display_info, 161 &dvi->bus_format, 1); 162 163 drm_connector_attach_encoder(&dvi->connector, encoder); 164 165 return 0; 166 } 167 168 static void tfp410_detach(struct drm_bridge *bridge) 169 { 170 struct tfp410 *dvi = drm_bridge_to_tfp410(bridge); 171 172 if (dvi->connector.dev && dvi->next_bridge->ops & DRM_BRIDGE_OP_HPD) { 173 drm_bridge_hpd_disable(dvi->next_bridge); 174 cancel_delayed_work_sync(&dvi->hpd_work); 175 } 176 } 177 178 static void tfp410_enable(struct drm_bridge *bridge) 179 { 180 struct tfp410 *dvi = drm_bridge_to_tfp410(bridge); 181 182 gpiod_set_value_cansleep(dvi->powerdown, 0); 183 } 184 185 static void tfp410_disable(struct drm_bridge *bridge) 186 { 187 struct tfp410 *dvi = drm_bridge_to_tfp410(bridge); 188 189 gpiod_set_value_cansleep(dvi->powerdown, 1); 190 } 191 192 static enum drm_mode_status tfp410_mode_valid(struct drm_bridge *bridge, 193 const struct drm_display_info *info, 194 const struct drm_display_mode *mode) 195 { 196 if (mode->clock < 25000) 197 return MODE_CLOCK_LOW; 198 199 if (mode->clock > 165000) 200 return MODE_CLOCK_HIGH; 201 202 return MODE_OK; 203 } 204 205 static u32 *tfp410_get_input_bus_fmts(struct drm_bridge *bridge, 206 struct drm_bridge_state *bridge_state, 207 struct drm_crtc_state *crtc_state, 208 struct drm_connector_state *conn_state, 209 u32 output_fmt, 210 unsigned int *num_input_fmts) 211 { 212 struct tfp410 *dvi = drm_bridge_to_tfp410(bridge); 213 u32 *input_fmts; 214 215 *num_input_fmts = 0; 216 217 input_fmts = kzalloc(sizeof(*input_fmts), GFP_KERNEL); 218 if (!input_fmts) 219 return NULL; 220 221 *num_input_fmts = 1; 222 input_fmts[0] = dvi->bus_format; 223 224 return input_fmts; 225 } 226 227 static int tfp410_atomic_check(struct drm_bridge *bridge, 228 struct drm_bridge_state *bridge_state, 229 struct drm_crtc_state *crtc_state, 230 struct drm_connector_state *conn_state) 231 { 232 struct tfp410 *dvi = drm_bridge_to_tfp410(bridge); 233 234 /* 235 * There might be flags negotiation supported in future. 236 * Set the bus flags in atomic_check statically for now. 237 */ 238 bridge_state->input_bus_cfg.flags = dvi->timings.input_bus_flags; 239 240 return 0; 241 } 242 243 static const struct drm_bridge_funcs tfp410_bridge_funcs = { 244 .attach = tfp410_attach, 245 .detach = tfp410_detach, 246 .enable = tfp410_enable, 247 .disable = tfp410_disable, 248 .mode_valid = tfp410_mode_valid, 249 .atomic_reset = drm_atomic_helper_bridge_reset, 250 .atomic_duplicate_state = drm_atomic_helper_bridge_duplicate_state, 251 .atomic_destroy_state = drm_atomic_helper_bridge_destroy_state, 252 .atomic_get_input_bus_fmts = tfp410_get_input_bus_fmts, 253 .atomic_check = tfp410_atomic_check, 254 }; 255 256 static const struct drm_bridge_timings tfp410_default_timings = { 257 .input_bus_flags = DRM_BUS_FLAG_PIXDATA_SAMPLE_POSEDGE 258 | DRM_BUS_FLAG_DE_HIGH, 259 .setup_time_ps = 1200, 260 .hold_time_ps = 1300, 261 }; 262 263 static int tfp410_parse_timings(struct tfp410 *dvi, bool i2c) 264 { 265 struct drm_bridge_timings *timings = &dvi->timings; 266 struct device_node *ep; 267 u32 pclk_sample = 0; 268 u32 bus_width = 24; 269 u32 deskew = 0; 270 271 /* Start with defaults. */ 272 *timings = tfp410_default_timings; 273 274 if (i2c) 275 /* 276 * In I2C mode timings are configured through the I2C interface. 277 * As the driver doesn't support I2C configuration yet, we just 278 * go with the defaults (BSEL=1, DSEL=1, DKEN=0, EDGE=1). 279 */ 280 return 0; 281 282 /* 283 * In non-I2C mode, timings are configured through the BSEL, DSEL, DKEN 284 * and EDGE pins. They are specified in DT through endpoint properties 285 * and vendor-specific properties. 286 */ 287 ep = of_graph_get_endpoint_by_regs(dvi->dev->of_node, 0, 0); 288 if (!ep) 289 return -EINVAL; 290 291 /* Get the sampling edge from the endpoint. */ 292 of_property_read_u32(ep, "pclk-sample", &pclk_sample); 293 of_property_read_u32(ep, "bus-width", &bus_width); 294 of_node_put(ep); 295 296 timings->input_bus_flags = DRM_BUS_FLAG_DE_HIGH; 297 298 switch (pclk_sample) { 299 case 0: 300 timings->input_bus_flags |= DRM_BUS_FLAG_PIXDATA_SAMPLE_NEGEDGE 301 | DRM_BUS_FLAG_SYNC_SAMPLE_NEGEDGE; 302 break; 303 case 1: 304 timings->input_bus_flags |= DRM_BUS_FLAG_PIXDATA_SAMPLE_POSEDGE 305 | DRM_BUS_FLAG_SYNC_SAMPLE_POSEDGE; 306 break; 307 default: 308 return -EINVAL; 309 } 310 311 switch (bus_width) { 312 case 12: 313 dvi->bus_format = MEDIA_BUS_FMT_RGB888_2X12_LE; 314 break; 315 case 24: 316 dvi->bus_format = MEDIA_BUS_FMT_RGB888_1X24; 317 break; 318 default: 319 return -EINVAL; 320 } 321 322 /* Get the setup and hold time from vendor-specific properties. */ 323 of_property_read_u32(dvi->dev->of_node, "ti,deskew", &deskew); 324 if (deskew > 7) 325 return -EINVAL; 326 327 timings->setup_time_ps = 1200 - 350 * ((s32)deskew - 4); 328 timings->hold_time_ps = max(0, 1300 + 350 * ((s32)deskew - 4)); 329 330 return 0; 331 } 332 333 static int tfp410_init(struct device *dev, bool i2c) 334 { 335 struct device_node *node; 336 struct tfp410 *dvi; 337 int ret; 338 339 if (!dev->of_node) { 340 dev_err(dev, "device-tree data is missing\n"); 341 return -ENXIO; 342 } 343 344 dvi = devm_drm_bridge_alloc(dev, struct tfp410, bridge, 345 &tfp410_bridge_funcs); 346 if (IS_ERR(dvi)) 347 return PTR_ERR(dvi); 348 349 dvi->dev = dev; 350 dev_set_drvdata(dev, dvi); 351 352 dvi->bridge.of_node = dev->of_node; 353 dvi->bridge.timings = &dvi->timings; 354 dvi->bridge.type = DRM_MODE_CONNECTOR_DVID; 355 356 ret = tfp410_parse_timings(dvi, i2c); 357 if (ret) 358 return ret; 359 360 /* Get the next bridge, connected to port@1. */ 361 node = of_graph_get_remote_node(dev->of_node, 1, -1); 362 if (!node) 363 return -ENODEV; 364 365 dvi->next_bridge = of_drm_find_bridge(node); 366 of_node_put(node); 367 368 if (!dvi->next_bridge) 369 return -EPROBE_DEFER; 370 371 /* Get the powerdown GPIO. */ 372 dvi->powerdown = devm_gpiod_get_optional(dev, "powerdown", 373 GPIOD_OUT_HIGH); 374 if (IS_ERR(dvi->powerdown)) { 375 dev_err(dev, "failed to parse powerdown gpio\n"); 376 return PTR_ERR(dvi->powerdown); 377 } 378 379 /* Register the DRM bridge. */ 380 drm_bridge_add(&dvi->bridge); 381 382 return 0; 383 } 384 385 static void tfp410_fini(struct device *dev) 386 { 387 struct tfp410 *dvi = dev_get_drvdata(dev); 388 389 drm_bridge_remove(&dvi->bridge); 390 } 391 392 static int tfp410_probe(struct platform_device *pdev) 393 { 394 return tfp410_init(&pdev->dev, false); 395 } 396 397 static void tfp410_remove(struct platform_device *pdev) 398 { 399 tfp410_fini(&pdev->dev); 400 } 401 402 static const struct of_device_id tfp410_match[] = { 403 { .compatible = "ti,tfp410" }, 404 {}, 405 }; 406 MODULE_DEVICE_TABLE(of, tfp410_match); 407 408 static struct platform_driver tfp410_platform_driver = { 409 .probe = tfp410_probe, 410 .remove = tfp410_remove, 411 .driver = { 412 .name = "tfp410-bridge", 413 .of_match_table = tfp410_match, 414 }, 415 }; 416 417 #if IS_ENABLED(CONFIG_I2C) 418 /* There is currently no i2c functionality. */ 419 static int tfp410_i2c_probe(struct i2c_client *client) 420 { 421 int reg; 422 423 if (!client->dev.of_node || 424 of_property_read_u32(client->dev.of_node, "reg", ®)) { 425 dev_err(&client->dev, 426 "Can't get i2c reg property from device-tree\n"); 427 return -ENXIO; 428 } 429 430 return tfp410_init(&client->dev, true); 431 } 432 433 static void tfp410_i2c_remove(struct i2c_client *client) 434 { 435 tfp410_fini(&client->dev); 436 } 437 438 static const struct i2c_device_id tfp410_i2c_ids[] = { 439 { "tfp410" }, 440 { } 441 }; 442 MODULE_DEVICE_TABLE(i2c, tfp410_i2c_ids); 443 444 static struct i2c_driver tfp410_i2c_driver = { 445 .driver = { 446 .name = "tfp410", 447 .of_match_table = tfp410_match, 448 }, 449 .id_table = tfp410_i2c_ids, 450 .probe = tfp410_i2c_probe, 451 .remove = tfp410_i2c_remove, 452 }; 453 #endif /* IS_ENABLED(CONFIG_I2C) */ 454 455 static struct { 456 uint i2c:1; 457 uint platform:1; 458 } tfp410_registered_driver; 459 460 static int __init tfp410_module_init(void) 461 { 462 int ret; 463 464 #if IS_ENABLED(CONFIG_I2C) 465 ret = i2c_add_driver(&tfp410_i2c_driver); 466 if (ret) 467 pr_err("%s: registering i2c driver failed: %d", 468 __func__, ret); 469 else 470 tfp410_registered_driver.i2c = 1; 471 #endif 472 473 ret = platform_driver_register(&tfp410_platform_driver); 474 if (ret) 475 pr_err("%s: registering platform driver failed: %d", 476 __func__, ret); 477 else 478 tfp410_registered_driver.platform = 1; 479 480 if (tfp410_registered_driver.i2c || 481 tfp410_registered_driver.platform) 482 return 0; 483 484 return ret; 485 } 486 module_init(tfp410_module_init); 487 488 static void __exit tfp410_module_exit(void) 489 { 490 #if IS_ENABLED(CONFIG_I2C) 491 if (tfp410_registered_driver.i2c) 492 i2c_del_driver(&tfp410_i2c_driver); 493 #endif 494 if (tfp410_registered_driver.platform) 495 platform_driver_unregister(&tfp410_platform_driver); 496 } 497 module_exit(tfp410_module_exit); 498 499 MODULE_AUTHOR("Jyri Sarha <jsarha@ti.com>"); 500 MODULE_DESCRIPTION("TI TFP410 DVI bridge driver"); 501 MODULE_LICENSE("GPL"); 502