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/module.h> 10 #include <linux/of_graph.h> 11 #include <linux/platform_device.h> 12 #include <linux/workqueue.h> 13 14 #include <drm/drm_atomic_helper.h> 15 #include <drm/drm_bridge.h> 16 #include <drm/drm_crtc.h> 17 #include <drm/drm_print.h> 18 #include <drm/drm_probe_helper.h> 19 20 #define HOTPLUG_DEBOUNCE_MS 1100 21 22 struct tfp410 { 23 struct drm_bridge bridge; 24 struct drm_connector connector; 25 26 u32 bus_format; 27 struct delayed_work hpd_work; 28 struct gpio_desc *powerdown; 29 30 struct drm_bridge_timings timings; 31 struct drm_bridge *next_bridge; 32 33 struct device *dev; 34 }; 35 36 static inline struct tfp410 * 37 drm_bridge_to_tfp410(struct drm_bridge *bridge) 38 { 39 return container_of(bridge, struct tfp410, bridge); 40 } 41 42 static inline struct tfp410 * 43 drm_connector_to_tfp410(struct drm_connector *connector) 44 { 45 return container_of(connector, struct tfp410, connector); 46 } 47 48 static int tfp410_get_modes(struct drm_connector *connector) 49 { 50 struct tfp410 *dvi = drm_connector_to_tfp410(connector); 51 struct edid *edid; 52 int ret; 53 54 if (dvi->next_bridge->ops & DRM_BRIDGE_OP_EDID) { 55 edid = drm_bridge_get_edid(dvi->next_bridge, connector); 56 if (!edid) 57 DRM_INFO("EDID read failed. Fallback to standard modes\n"); 58 } else { 59 edid = NULL; 60 } 61 62 if (!edid) { 63 /* 64 * No EDID, fallback on the XGA standard modes and prefer a mode 65 * pretty much anything can handle. 66 */ 67 ret = drm_add_modes_noedid(connector, 1920, 1200); 68 drm_set_preferred_mode(connector, 1024, 768); 69 return ret; 70 } 71 72 drm_connector_update_edid_property(connector, edid); 73 74 ret = drm_add_edid_modes(connector, edid); 75 76 kfree(edid); 77 78 return ret; 79 } 80 81 static const struct drm_connector_helper_funcs tfp410_con_helper_funcs = { 82 .get_modes = tfp410_get_modes, 83 }; 84 85 static enum drm_connector_status 86 tfp410_connector_detect(struct drm_connector *connector, bool force) 87 { 88 struct tfp410 *dvi = drm_connector_to_tfp410(connector); 89 90 return drm_bridge_detect(dvi->next_bridge); 91 } 92 93 static const struct drm_connector_funcs tfp410_con_funcs = { 94 .detect = tfp410_connector_detect, 95 .fill_modes = drm_helper_probe_single_connector_modes, 96 .destroy = drm_connector_cleanup, 97 .reset = drm_atomic_helper_connector_reset, 98 .atomic_duplicate_state = drm_atomic_helper_connector_duplicate_state, 99 .atomic_destroy_state = drm_atomic_helper_connector_destroy_state, 100 }; 101 102 static void tfp410_hpd_work_func(struct work_struct *work) 103 { 104 struct tfp410 *dvi; 105 106 dvi = container_of(work, struct tfp410, hpd_work.work); 107 108 if (dvi->bridge.dev) 109 drm_helper_hpd_irq_event(dvi->bridge.dev); 110 } 111 112 static void tfp410_hpd_callback(void *arg, enum drm_connector_status status) 113 { 114 struct tfp410 *dvi = arg; 115 116 mod_delayed_work(system_wq, &dvi->hpd_work, 117 msecs_to_jiffies(HOTPLUG_DEBOUNCE_MS)); 118 } 119 120 static int tfp410_attach(struct drm_bridge *bridge, 121 enum drm_bridge_attach_flags flags) 122 { 123 struct tfp410 *dvi = drm_bridge_to_tfp410(bridge); 124 int ret; 125 126 ret = drm_bridge_attach(bridge->encoder, dvi->next_bridge, bridge, 127 DRM_BRIDGE_ATTACH_NO_CONNECTOR); 128 if (ret < 0) 129 return ret; 130 131 if (flags & DRM_BRIDGE_ATTACH_NO_CONNECTOR) 132 return 0; 133 134 if (!bridge->encoder) { 135 dev_err(dvi->dev, "Missing encoder\n"); 136 return -ENODEV; 137 } 138 139 if (dvi->next_bridge->ops & DRM_BRIDGE_OP_DETECT) 140 dvi->connector.polled = DRM_CONNECTOR_POLL_HPD; 141 else 142 dvi->connector.polled = DRM_CONNECTOR_POLL_CONNECT | DRM_CONNECTOR_POLL_DISCONNECT; 143 144 if (dvi->next_bridge->ops & DRM_BRIDGE_OP_HPD) { 145 INIT_DELAYED_WORK(&dvi->hpd_work, tfp410_hpd_work_func); 146 drm_bridge_hpd_enable(dvi->next_bridge, tfp410_hpd_callback, 147 dvi); 148 } 149 150 drm_connector_helper_add(&dvi->connector, 151 &tfp410_con_helper_funcs); 152 ret = drm_connector_init_with_ddc(bridge->dev, &dvi->connector, 153 &tfp410_con_funcs, 154 dvi->next_bridge->type, 155 dvi->next_bridge->ddc); 156 if (ret) { 157 dev_err(dvi->dev, "drm_connector_init_with_ddc() failed: %d\n", 158 ret); 159 return ret; 160 } 161 162 drm_display_info_set_bus_formats(&dvi->connector.display_info, 163 &dvi->bus_format, 1); 164 165 drm_connector_attach_encoder(&dvi->connector, bridge->encoder); 166 167 return 0; 168 } 169 170 static void tfp410_detach(struct drm_bridge *bridge) 171 { 172 struct tfp410 *dvi = drm_bridge_to_tfp410(bridge); 173 174 if (dvi->connector.dev && dvi->next_bridge->ops & DRM_BRIDGE_OP_HPD) { 175 drm_bridge_hpd_disable(dvi->next_bridge); 176 cancel_delayed_work_sync(&dvi->hpd_work); 177 } 178 } 179 180 static void tfp410_enable(struct drm_bridge *bridge) 181 { 182 struct tfp410 *dvi = drm_bridge_to_tfp410(bridge); 183 184 gpiod_set_value_cansleep(dvi->powerdown, 0); 185 } 186 187 static void tfp410_disable(struct drm_bridge *bridge) 188 { 189 struct tfp410 *dvi = drm_bridge_to_tfp410(bridge); 190 191 gpiod_set_value_cansleep(dvi->powerdown, 1); 192 } 193 194 static enum drm_mode_status tfp410_mode_valid(struct drm_bridge *bridge, 195 const struct drm_display_info *info, 196 const struct drm_display_mode *mode) 197 { 198 if (mode->clock < 25000) 199 return MODE_CLOCK_LOW; 200 201 if (mode->clock > 165000) 202 return MODE_CLOCK_HIGH; 203 204 return MODE_OK; 205 } 206 207 static const struct drm_bridge_funcs tfp410_bridge_funcs = { 208 .attach = tfp410_attach, 209 .detach = tfp410_detach, 210 .enable = tfp410_enable, 211 .disable = tfp410_disable, 212 .mode_valid = tfp410_mode_valid, 213 }; 214 215 static const struct drm_bridge_timings tfp410_default_timings = { 216 .input_bus_flags = DRM_BUS_FLAG_PIXDATA_SAMPLE_POSEDGE 217 | DRM_BUS_FLAG_DE_HIGH, 218 .setup_time_ps = 1200, 219 .hold_time_ps = 1300, 220 }; 221 222 static int tfp410_parse_timings(struct tfp410 *dvi, bool i2c) 223 { 224 struct drm_bridge_timings *timings = &dvi->timings; 225 struct device_node *ep; 226 u32 pclk_sample = 0; 227 u32 bus_width = 24; 228 u32 deskew = 0; 229 230 /* Start with defaults. */ 231 *timings = tfp410_default_timings; 232 233 if (i2c) 234 /* 235 * In I2C mode timings are configured through the I2C interface. 236 * As the driver doesn't support I2C configuration yet, we just 237 * go with the defaults (BSEL=1, DSEL=1, DKEN=0, EDGE=1). 238 */ 239 return 0; 240 241 /* 242 * In non-I2C mode, timings are configured through the BSEL, DSEL, DKEN 243 * and EDGE pins. They are specified in DT through endpoint properties 244 * and vendor-specific properties. 245 */ 246 ep = of_graph_get_endpoint_by_regs(dvi->dev->of_node, 0, 0); 247 if (!ep) 248 return -EINVAL; 249 250 /* Get the sampling edge from the endpoint. */ 251 of_property_read_u32(ep, "pclk-sample", &pclk_sample); 252 of_property_read_u32(ep, "bus-width", &bus_width); 253 of_node_put(ep); 254 255 timings->input_bus_flags = DRM_BUS_FLAG_DE_HIGH; 256 257 switch (pclk_sample) { 258 case 0: 259 timings->input_bus_flags |= DRM_BUS_FLAG_PIXDATA_SAMPLE_NEGEDGE 260 | DRM_BUS_FLAG_SYNC_SAMPLE_NEGEDGE; 261 break; 262 case 1: 263 timings->input_bus_flags |= DRM_BUS_FLAG_PIXDATA_SAMPLE_POSEDGE 264 | DRM_BUS_FLAG_SYNC_SAMPLE_POSEDGE; 265 break; 266 default: 267 return -EINVAL; 268 } 269 270 switch (bus_width) { 271 case 12: 272 dvi->bus_format = MEDIA_BUS_FMT_RGB888_2X12_LE; 273 break; 274 case 24: 275 dvi->bus_format = MEDIA_BUS_FMT_RGB888_1X24; 276 break; 277 default: 278 return -EINVAL; 279 } 280 281 /* Get the setup and hold time from vendor-specific properties. */ 282 of_property_read_u32(dvi->dev->of_node, "ti,deskew", &deskew); 283 if (deskew > 7) 284 return -EINVAL; 285 286 timings->setup_time_ps = 1200 - 350 * ((s32)deskew - 4); 287 timings->hold_time_ps = max(0, 1300 + 350 * ((s32)deskew - 4)); 288 289 return 0; 290 } 291 292 static int tfp410_init(struct device *dev, bool i2c) 293 { 294 struct device_node *node; 295 struct tfp410 *dvi; 296 int ret; 297 298 if (!dev->of_node) { 299 dev_err(dev, "device-tree data is missing\n"); 300 return -ENXIO; 301 } 302 303 dvi = devm_kzalloc(dev, sizeof(*dvi), GFP_KERNEL); 304 if (!dvi) 305 return -ENOMEM; 306 307 dvi->dev = dev; 308 dev_set_drvdata(dev, dvi); 309 310 dvi->bridge.funcs = &tfp410_bridge_funcs; 311 dvi->bridge.of_node = dev->of_node; 312 dvi->bridge.timings = &dvi->timings; 313 dvi->bridge.type = DRM_MODE_CONNECTOR_DVID; 314 315 ret = tfp410_parse_timings(dvi, i2c); 316 if (ret) 317 return ret; 318 319 /* Get the next bridge, connected to port@1. */ 320 node = of_graph_get_remote_node(dev->of_node, 1, -1); 321 if (!node) 322 return -ENODEV; 323 324 dvi->next_bridge = of_drm_find_bridge(node); 325 of_node_put(node); 326 327 if (!dvi->next_bridge) 328 return -EPROBE_DEFER; 329 330 /* Get the powerdown GPIO. */ 331 dvi->powerdown = devm_gpiod_get_optional(dev, "powerdown", 332 GPIOD_OUT_HIGH); 333 if (IS_ERR(dvi->powerdown)) { 334 dev_err(dev, "failed to parse powerdown gpio\n"); 335 return PTR_ERR(dvi->powerdown); 336 } 337 338 /* Register the DRM bridge. */ 339 drm_bridge_add(&dvi->bridge); 340 341 return 0; 342 } 343 344 static void tfp410_fini(struct device *dev) 345 { 346 struct tfp410 *dvi = dev_get_drvdata(dev); 347 348 drm_bridge_remove(&dvi->bridge); 349 } 350 351 static int tfp410_probe(struct platform_device *pdev) 352 { 353 return tfp410_init(&pdev->dev, false); 354 } 355 356 static int tfp410_remove(struct platform_device *pdev) 357 { 358 tfp410_fini(&pdev->dev); 359 360 return 0; 361 } 362 363 static const struct of_device_id tfp410_match[] = { 364 { .compatible = "ti,tfp410" }, 365 {}, 366 }; 367 MODULE_DEVICE_TABLE(of, tfp410_match); 368 369 static struct platform_driver tfp410_platform_driver = { 370 .probe = tfp410_probe, 371 .remove = tfp410_remove, 372 .driver = { 373 .name = "tfp410-bridge", 374 .of_match_table = tfp410_match, 375 }, 376 }; 377 378 #if IS_ENABLED(CONFIG_I2C) 379 /* There is currently no i2c functionality. */ 380 static int tfp410_i2c_probe(struct i2c_client *client, 381 const struct i2c_device_id *id) 382 { 383 int reg; 384 385 if (!client->dev.of_node || 386 of_property_read_u32(client->dev.of_node, "reg", ®)) { 387 dev_err(&client->dev, 388 "Can't get i2c reg property from device-tree\n"); 389 return -ENXIO; 390 } 391 392 return tfp410_init(&client->dev, true); 393 } 394 395 static int tfp410_i2c_remove(struct i2c_client *client) 396 { 397 tfp410_fini(&client->dev); 398 399 return 0; 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 <jsarha@ti.com>"); 464 MODULE_DESCRIPTION("TI TFP410 DVI bridge driver"); 465 MODULE_LICENSE("GPL"); 466