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 (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_new = 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", ®)) { 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", 0 }, 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 <jsarha@ti.com>"); 499 MODULE_DESCRIPTION("TI TFP410 DVI bridge driver"); 500 MODULE_LICENSE("GPL"); 501