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 edid = drm_bridge_get_edid(dvi->next_bridge, connector); 55 if (IS_ERR_OR_NULL(edid)) { 56 if (edid != ERR_PTR(-ENOTSUPP)) 57 DRM_INFO("EDID read failed. Fallback to standard modes\n"); 58 59 /* 60 * No EDID, fallback on the XGA standard modes and prefer a mode 61 * pretty much anything can handle. 62 */ 63 ret = drm_add_modes_noedid(connector, 1920, 1200); 64 drm_set_preferred_mode(connector, 1024, 768); 65 return ret; 66 } 67 68 drm_connector_update_edid_property(connector, edid); 69 70 ret = drm_add_edid_modes(connector, edid); 71 72 kfree(edid); 73 74 return ret; 75 } 76 77 static const struct drm_connector_helper_funcs tfp410_con_helper_funcs = { 78 .get_modes = tfp410_get_modes, 79 }; 80 81 static enum drm_connector_status 82 tfp410_connector_detect(struct drm_connector *connector, bool force) 83 { 84 struct tfp410 *dvi = drm_connector_to_tfp410(connector); 85 86 return drm_bridge_detect(dvi->next_bridge); 87 } 88 89 static const struct drm_connector_funcs tfp410_con_funcs = { 90 .detect = tfp410_connector_detect, 91 .fill_modes = drm_helper_probe_single_connector_modes, 92 .destroy = drm_connector_cleanup, 93 .reset = drm_atomic_helper_connector_reset, 94 .atomic_duplicate_state = drm_atomic_helper_connector_duplicate_state, 95 .atomic_destroy_state = drm_atomic_helper_connector_destroy_state, 96 }; 97 98 static void tfp410_hpd_work_func(struct work_struct *work) 99 { 100 struct tfp410 *dvi; 101 102 dvi = container_of(work, struct tfp410, hpd_work.work); 103 104 if (dvi->bridge.dev) 105 drm_helper_hpd_irq_event(dvi->bridge.dev); 106 } 107 108 static void tfp410_hpd_callback(void *arg, enum drm_connector_status status) 109 { 110 struct tfp410 *dvi = arg; 111 112 mod_delayed_work(system_wq, &dvi->hpd_work, 113 msecs_to_jiffies(HOTPLUG_DEBOUNCE_MS)); 114 } 115 116 static int tfp410_attach(struct drm_bridge *bridge, 117 enum drm_bridge_attach_flags flags) 118 { 119 struct tfp410 *dvi = drm_bridge_to_tfp410(bridge); 120 int ret; 121 122 ret = drm_bridge_attach(bridge->encoder, dvi->next_bridge, bridge, 123 DRM_BRIDGE_ATTACH_NO_CONNECTOR); 124 if (ret < 0) 125 return ret; 126 127 if (flags & DRM_BRIDGE_ATTACH_NO_CONNECTOR) 128 return 0; 129 130 if (!bridge->encoder) { 131 dev_err(dvi->dev, "Missing encoder\n"); 132 return -ENODEV; 133 } 134 135 if (dvi->next_bridge->ops & DRM_BRIDGE_OP_DETECT) 136 dvi->connector.polled = DRM_CONNECTOR_POLL_HPD; 137 else 138 dvi->connector.polled = DRM_CONNECTOR_POLL_CONNECT | DRM_CONNECTOR_POLL_DISCONNECT; 139 140 if (dvi->next_bridge->ops & DRM_BRIDGE_OP_HPD) { 141 INIT_DELAYED_WORK(&dvi->hpd_work, tfp410_hpd_work_func); 142 drm_bridge_hpd_enable(dvi->next_bridge, tfp410_hpd_callback, 143 dvi); 144 } 145 146 drm_connector_helper_add(&dvi->connector, 147 &tfp410_con_helper_funcs); 148 ret = drm_connector_init_with_ddc(bridge->dev, &dvi->connector, 149 &tfp410_con_funcs, 150 dvi->next_bridge->type, 151 dvi->next_bridge->ddc); 152 if (ret) { 153 dev_err(dvi->dev, "drm_connector_init_with_ddc() failed: %d\n", 154 ret); 155 return ret; 156 } 157 158 drm_display_info_set_bus_formats(&dvi->connector.display_info, 159 &dvi->bus_format, 1); 160 161 drm_connector_attach_encoder(&dvi->connector, bridge->encoder); 162 163 return 0; 164 } 165 166 static void tfp410_detach(struct drm_bridge *bridge) 167 { 168 struct tfp410 *dvi = drm_bridge_to_tfp410(bridge); 169 170 if (dvi->connector.dev && dvi->next_bridge->ops & DRM_BRIDGE_OP_HPD) { 171 drm_bridge_hpd_disable(dvi->next_bridge); 172 cancel_delayed_work_sync(&dvi->hpd_work); 173 } 174 } 175 176 static void tfp410_enable(struct drm_bridge *bridge) 177 { 178 struct tfp410 *dvi = drm_bridge_to_tfp410(bridge); 179 180 gpiod_set_value_cansleep(dvi->powerdown, 0); 181 } 182 183 static void tfp410_disable(struct drm_bridge *bridge) 184 { 185 struct tfp410 *dvi = drm_bridge_to_tfp410(bridge); 186 187 gpiod_set_value_cansleep(dvi->powerdown, 1); 188 } 189 190 static enum drm_mode_status tfp410_mode_valid(struct drm_bridge *bridge, 191 const struct drm_display_mode *mode) 192 { 193 if (mode->clock < 25000) 194 return MODE_CLOCK_LOW; 195 196 if (mode->clock > 165000) 197 return MODE_CLOCK_HIGH; 198 199 return MODE_OK; 200 } 201 202 static const struct drm_bridge_funcs tfp410_bridge_funcs = { 203 .attach = tfp410_attach, 204 .detach = tfp410_detach, 205 .enable = tfp410_enable, 206 .disable = tfp410_disable, 207 .mode_valid = tfp410_mode_valid, 208 }; 209 210 static const struct drm_bridge_timings tfp410_default_timings = { 211 .input_bus_flags = DRM_BUS_FLAG_PIXDATA_SAMPLE_POSEDGE 212 | DRM_BUS_FLAG_DE_HIGH, 213 .setup_time_ps = 1200, 214 .hold_time_ps = 1300, 215 }; 216 217 static int tfp410_parse_timings(struct tfp410 *dvi, bool i2c) 218 { 219 struct drm_bridge_timings *timings = &dvi->timings; 220 struct device_node *ep; 221 u32 pclk_sample = 0; 222 u32 bus_width = 24; 223 s32 deskew = 0; 224 225 /* Start with defaults. */ 226 *timings = tfp410_default_timings; 227 228 if (i2c) 229 /* 230 * In I2C mode timings are configured through the I2C interface. 231 * As the driver doesn't support I2C configuration yet, we just 232 * go with the defaults (BSEL=1, DSEL=1, DKEN=0, EDGE=1). 233 */ 234 return 0; 235 236 /* 237 * In non-I2C mode, timings are configured through the BSEL, DSEL, DKEN 238 * and EDGE pins. They are specified in DT through endpoint properties 239 * and vendor-specific properties. 240 */ 241 ep = of_graph_get_endpoint_by_regs(dvi->dev->of_node, 0, 0); 242 if (!ep) 243 return -EINVAL; 244 245 /* Get the sampling edge from the endpoint. */ 246 of_property_read_u32(ep, "pclk-sample", &pclk_sample); 247 of_property_read_u32(ep, "bus-width", &bus_width); 248 of_node_put(ep); 249 250 timings->input_bus_flags = DRM_BUS_FLAG_DE_HIGH; 251 252 switch (pclk_sample) { 253 case 0: 254 timings->input_bus_flags |= DRM_BUS_FLAG_PIXDATA_SAMPLE_NEGEDGE 255 | DRM_BUS_FLAG_SYNC_SAMPLE_NEGEDGE; 256 break; 257 case 1: 258 timings->input_bus_flags |= DRM_BUS_FLAG_PIXDATA_SAMPLE_POSEDGE 259 | DRM_BUS_FLAG_SYNC_SAMPLE_POSEDGE; 260 break; 261 default: 262 return -EINVAL; 263 } 264 265 switch (bus_width) { 266 case 12: 267 dvi->bus_format = MEDIA_BUS_FMT_RGB888_2X12_LE; 268 break; 269 case 24: 270 dvi->bus_format = MEDIA_BUS_FMT_RGB888_1X24; 271 break; 272 default: 273 return -EINVAL; 274 } 275 276 /* Get the setup and hold time from vendor-specific properties. */ 277 of_property_read_u32(dvi->dev->of_node, "ti,deskew", (u32 *)&deskew); 278 if (deskew < -4 || deskew > 3) 279 return -EINVAL; 280 281 timings->setup_time_ps = min(0, 1200 - 350 * deskew); 282 timings->hold_time_ps = min(0, 1300 + 350 * deskew); 283 284 return 0; 285 } 286 287 static int tfp410_init(struct device *dev, bool i2c) 288 { 289 struct device_node *node; 290 struct tfp410 *dvi; 291 int ret; 292 293 if (!dev->of_node) { 294 dev_err(dev, "device-tree data is missing\n"); 295 return -ENXIO; 296 } 297 298 dvi = devm_kzalloc(dev, sizeof(*dvi), GFP_KERNEL); 299 if (!dvi) 300 return -ENOMEM; 301 302 dvi->dev = dev; 303 dev_set_drvdata(dev, dvi); 304 305 dvi->bridge.funcs = &tfp410_bridge_funcs; 306 dvi->bridge.of_node = dev->of_node; 307 dvi->bridge.timings = &dvi->timings; 308 dvi->bridge.type = DRM_MODE_CONNECTOR_DVID; 309 310 ret = tfp410_parse_timings(dvi, i2c); 311 if (ret) 312 return ret; 313 314 /* Get the next bridge, connected to port@1. */ 315 node = of_graph_get_remote_node(dev->of_node, 1, -1); 316 if (!node) 317 return -ENODEV; 318 319 dvi->next_bridge = of_drm_find_bridge(node); 320 of_node_put(node); 321 322 if (!dvi->next_bridge) 323 return -EPROBE_DEFER; 324 325 /* Get the powerdown GPIO. */ 326 dvi->powerdown = devm_gpiod_get_optional(dev, "powerdown", 327 GPIOD_OUT_HIGH); 328 if (IS_ERR(dvi->powerdown)) { 329 dev_err(dev, "failed to parse powerdown gpio\n"); 330 return PTR_ERR(dvi->powerdown); 331 } 332 333 /* Register the DRM bridge. */ 334 drm_bridge_add(&dvi->bridge); 335 336 return 0; 337 } 338 339 static int tfp410_fini(struct device *dev) 340 { 341 struct tfp410 *dvi = dev_get_drvdata(dev); 342 343 drm_bridge_remove(&dvi->bridge); 344 345 return 0; 346 } 347 348 static int tfp410_probe(struct platform_device *pdev) 349 { 350 return tfp410_init(&pdev->dev, false); 351 } 352 353 static int tfp410_remove(struct platform_device *pdev) 354 { 355 return tfp410_fini(&pdev->dev); 356 } 357 358 static const struct of_device_id tfp410_match[] = { 359 { .compatible = "ti,tfp410" }, 360 {}, 361 }; 362 MODULE_DEVICE_TABLE(of, tfp410_match); 363 364 static struct platform_driver tfp410_platform_driver = { 365 .probe = tfp410_probe, 366 .remove = tfp410_remove, 367 .driver = { 368 .name = "tfp410-bridge", 369 .of_match_table = tfp410_match, 370 }, 371 }; 372 373 #if IS_ENABLED(CONFIG_I2C) 374 /* There is currently no i2c functionality. */ 375 static int tfp410_i2c_probe(struct i2c_client *client, 376 const struct i2c_device_id *id) 377 { 378 int reg; 379 380 if (!client->dev.of_node || 381 of_property_read_u32(client->dev.of_node, "reg", ®)) { 382 dev_err(&client->dev, 383 "Can't get i2c reg property from device-tree\n"); 384 return -ENXIO; 385 } 386 387 return tfp410_init(&client->dev, true); 388 } 389 390 static int tfp410_i2c_remove(struct i2c_client *client) 391 { 392 return tfp410_fini(&client->dev); 393 } 394 395 static const struct i2c_device_id tfp410_i2c_ids[] = { 396 { "tfp410", 0 }, 397 { } 398 }; 399 MODULE_DEVICE_TABLE(i2c, tfp410_i2c_ids); 400 401 static struct i2c_driver tfp410_i2c_driver = { 402 .driver = { 403 .name = "tfp410", 404 .of_match_table = of_match_ptr(tfp410_match), 405 }, 406 .id_table = tfp410_i2c_ids, 407 .probe = tfp410_i2c_probe, 408 .remove = tfp410_i2c_remove, 409 }; 410 #endif /* IS_ENABLED(CONFIG_I2C) */ 411 412 static struct { 413 uint i2c:1; 414 uint platform:1; 415 } tfp410_registered_driver; 416 417 static int __init tfp410_module_init(void) 418 { 419 int ret; 420 421 #if IS_ENABLED(CONFIG_I2C) 422 ret = i2c_add_driver(&tfp410_i2c_driver); 423 if (ret) 424 pr_err("%s: registering i2c driver failed: %d", 425 __func__, ret); 426 else 427 tfp410_registered_driver.i2c = 1; 428 #endif 429 430 ret = platform_driver_register(&tfp410_platform_driver); 431 if (ret) 432 pr_err("%s: registering platform driver failed: %d", 433 __func__, ret); 434 else 435 tfp410_registered_driver.platform = 1; 436 437 if (tfp410_registered_driver.i2c || 438 tfp410_registered_driver.platform) 439 return 0; 440 441 return ret; 442 } 443 module_init(tfp410_module_init); 444 445 static void __exit tfp410_module_exit(void) 446 { 447 #if IS_ENABLED(CONFIG_I2C) 448 if (tfp410_registered_driver.i2c) 449 i2c_del_driver(&tfp410_i2c_driver); 450 #endif 451 if (tfp410_registered_driver.platform) 452 platform_driver_unregister(&tfp410_platform_driver); 453 } 454 module_exit(tfp410_module_exit); 455 456 MODULE_AUTHOR("Jyri Sarha <jsarha@ti.com>"); 457 MODULE_DESCRIPTION("TI TFP410 DVI bridge driver"); 458 MODULE_LICENSE("GPL"); 459