1 // SPDX-License-Identifier: GPL-2.0+ 2 /* 3 * CEC driver for ChromeOS Embedded Controller 4 * 5 * Copyright (c) 2018 BayLibre, SAS 6 * Author: Neil Armstrong <narmstrong@baylibre.com> 7 */ 8 9 #include <linux/kernel.h> 10 #include <linux/module.h> 11 #include <linux/platform_device.h> 12 #include <linux/dmi.h> 13 #include <linux/pci.h> 14 #include <linux/cec.h> 15 #include <linux/slab.h> 16 #include <linux/interrupt.h> 17 #include <linux/platform_data/cros_ec_commands.h> 18 #include <linux/platform_data/cros_ec_proto.h> 19 #include <media/cec.h> 20 #include <media/cec-notifier.h> 21 22 #define DRV_NAME "cros-ec-cec" 23 24 /** 25 * struct cros_ec_cec_port - Driver data for a single EC CEC port 26 * 27 * @port_num: port number 28 * @adap: CEC adapter 29 * @notify: CEC notifier pointer 30 * @rx_msg: storage for a received message 31 * @cros_ec_cec: pointer to the parent struct 32 */ 33 struct cros_ec_cec_port { 34 int port_num; 35 struct cec_adapter *adap; 36 struct cec_notifier *notify; 37 struct cec_msg rx_msg; 38 struct cros_ec_cec *cros_ec_cec; 39 }; 40 41 /** 42 * struct cros_ec_cec - Driver data for EC CEC 43 * 44 * @cros_ec: Pointer to EC device 45 * @notifier: Notifier info for responding to EC events 46 * @write_cmd_version: Highest supported version of EC_CMD_CEC_WRITE_MSG. 47 * @num_ports: Number of CEC ports 48 * @ports: Array of ports 49 */ 50 struct cros_ec_cec { 51 struct cros_ec_device *cros_ec; 52 struct notifier_block notifier; 53 int write_cmd_version; 54 int num_ports; 55 struct cros_ec_cec_port *ports[EC_CEC_MAX_PORTS]; 56 }; 57 58 static void cros_ec_cec_received_message(struct cros_ec_cec_port *port, 59 uint8_t *msg, uint8_t len) 60 { 61 if (len > CEC_MAX_MSG_SIZE) 62 len = CEC_MAX_MSG_SIZE; 63 64 port->rx_msg.len = len; 65 memcpy(port->rx_msg.msg, msg, len); 66 67 cec_received_msg(port->adap, &port->rx_msg); 68 } 69 70 static void handle_cec_message(struct cros_ec_cec *cros_ec_cec) 71 { 72 struct cros_ec_device *cros_ec = cros_ec_cec->cros_ec; 73 uint8_t *cec_message = cros_ec->event_data.data.cec_message; 74 unsigned int len = cros_ec->event_size; 75 struct cros_ec_cec_port *port; 76 /* 77 * There are two ways of receiving CEC messages: 78 * 1. Old EC firmware which only supports one port sends the data in a 79 * cec_message MKBP event. 80 * 2. New EC firmware which supports multiple ports uses 81 * EC_MKBP_CEC_HAVE_DATA to notify that data is ready and 82 * EC_CMD_CEC_READ_MSG to read it. 83 * Check that the EC only has one CEC port, and then we can assume the 84 * message is from port 0. 85 */ 86 if (cros_ec_cec->num_ports != 1) { 87 dev_err(cros_ec->dev, 88 "received cec_message on device with %d ports\n", 89 cros_ec_cec->num_ports); 90 return; 91 } 92 port = cros_ec_cec->ports[0]; 93 94 cros_ec_cec_received_message(port, cec_message, len); 95 } 96 97 static void cros_ec_cec_read_message(struct cros_ec_cec_port *port) 98 { 99 struct cros_ec_device *cros_ec = port->cros_ec_cec->cros_ec; 100 struct ec_params_cec_read params = { 101 .port = port->port_num, 102 }; 103 struct ec_response_cec_read response; 104 int ret; 105 106 ret = cros_ec_cmd(cros_ec, 0, EC_CMD_CEC_READ_MSG, ¶ms, 107 sizeof(params), &response, sizeof(response)); 108 if (ret < 0) { 109 dev_err(cros_ec->dev, 110 "error reading CEC message on EC: %d\n", ret); 111 return; 112 } 113 114 cros_ec_cec_received_message(port, response.msg, response.msg_len); 115 } 116 117 static void handle_cec_event(struct cros_ec_cec *cros_ec_cec) 118 { 119 struct cros_ec_device *cros_ec = cros_ec_cec->cros_ec; 120 uint32_t cec_events = cros_ec->event_data.data.cec_events; 121 uint32_t port_num = EC_MKBP_EVENT_CEC_GET_PORT(cec_events); 122 uint32_t events = EC_MKBP_EVENT_CEC_GET_EVENTS(cec_events); 123 struct cros_ec_cec_port *port; 124 125 if (port_num >= cros_ec_cec->num_ports) { 126 dev_err(cros_ec->dev, 127 "received CEC event for invalid port %d\n", port_num); 128 return; 129 } 130 port = cros_ec_cec->ports[port_num]; 131 132 if (events & EC_MKBP_CEC_SEND_OK) 133 cec_transmit_attempt_done(port->adap, CEC_TX_STATUS_OK); 134 135 /* FW takes care of all retries, tell core to avoid more retries */ 136 if (events & EC_MKBP_CEC_SEND_FAILED) 137 cec_transmit_attempt_done(port->adap, 138 CEC_TX_STATUS_MAX_RETRIES | 139 CEC_TX_STATUS_NACK); 140 141 if (events & EC_MKBP_CEC_HAVE_DATA) 142 cros_ec_cec_read_message(port); 143 } 144 145 static int cros_ec_cec_event(struct notifier_block *nb, 146 unsigned long queued_during_suspend, 147 void *_notify) 148 { 149 struct cros_ec_cec *cros_ec_cec; 150 struct cros_ec_device *cros_ec; 151 152 cros_ec_cec = container_of(nb, struct cros_ec_cec, notifier); 153 cros_ec = cros_ec_cec->cros_ec; 154 155 if (cros_ec->event_data.event_type == EC_MKBP_EVENT_CEC_EVENT) { 156 handle_cec_event(cros_ec_cec); 157 return NOTIFY_OK; 158 } 159 160 if (cros_ec->event_data.event_type == EC_MKBP_EVENT_CEC_MESSAGE) { 161 handle_cec_message(cros_ec_cec); 162 return NOTIFY_OK; 163 } 164 165 return NOTIFY_DONE; 166 } 167 168 static int cros_ec_cec_set_log_addr(struct cec_adapter *adap, u8 logical_addr) 169 { 170 struct cros_ec_cec_port *port = adap->priv; 171 struct cros_ec_cec *cros_ec_cec = port->cros_ec_cec; 172 struct cros_ec_device *cros_ec = cros_ec_cec->cros_ec; 173 struct ec_params_cec_set params = { 174 .cmd = CEC_CMD_LOGICAL_ADDRESS, 175 .port = port->port_num, 176 .val = logical_addr, 177 }; 178 int ret; 179 180 ret = cros_ec_cmd(cros_ec, 0, EC_CMD_CEC_SET, ¶ms, sizeof(params), 181 NULL, 0); 182 if (ret < 0) { 183 dev_err(cros_ec->dev, 184 "error setting CEC logical address on EC: %d\n", ret); 185 return ret; 186 } 187 188 return 0; 189 } 190 191 static int cros_ec_cec_transmit(struct cec_adapter *adap, u8 attempts, 192 u32 signal_free_time, struct cec_msg *cec_msg) 193 { 194 struct cros_ec_cec_port *port = adap->priv; 195 struct cros_ec_cec *cros_ec_cec = port->cros_ec_cec; 196 struct cros_ec_device *cros_ec = cros_ec_cec->cros_ec; 197 struct ec_params_cec_write params; 198 struct ec_params_cec_write_v1 params_v1; 199 int ret; 200 201 if (cros_ec_cec->write_cmd_version == 0) { 202 memcpy(params.msg, cec_msg->msg, cec_msg->len); 203 ret = cros_ec_cmd(cros_ec, 0, EC_CMD_CEC_WRITE_MSG, ¶ms, 204 cec_msg->len, NULL, 0); 205 } else { 206 params_v1.port = port->port_num; 207 params_v1.msg_len = cec_msg->len; 208 memcpy(params_v1.msg, cec_msg->msg, cec_msg->len); 209 ret = cros_ec_cmd(cros_ec, cros_ec_cec->write_cmd_version, 210 EC_CMD_CEC_WRITE_MSG, ¶ms_v1, 211 sizeof(params_v1), NULL, 0); 212 } 213 214 if (ret < 0) { 215 dev_err(cros_ec->dev, 216 "error writing CEC msg on EC: %d\n", ret); 217 return ret; 218 } 219 220 return 0; 221 } 222 223 static int cros_ec_cec_adap_enable(struct cec_adapter *adap, bool enable) 224 { 225 struct cros_ec_cec_port *port = adap->priv; 226 struct cros_ec_cec *cros_ec_cec = port->cros_ec_cec; 227 struct cros_ec_device *cros_ec = cros_ec_cec->cros_ec; 228 struct ec_params_cec_set params = { 229 .cmd = CEC_CMD_ENABLE, 230 .port = port->port_num, 231 .val = enable, 232 }; 233 int ret; 234 235 ret = cros_ec_cmd(cros_ec, 0, EC_CMD_CEC_SET, ¶ms, sizeof(params), 236 NULL, 0); 237 if (ret < 0) { 238 dev_err(cros_ec->dev, 239 "error %sabling CEC on EC: %d\n", 240 (enable ? "en" : "dis"), ret); 241 return ret; 242 } 243 244 return 0; 245 } 246 247 static const struct cec_adap_ops cros_ec_cec_ops = { 248 .adap_enable = cros_ec_cec_adap_enable, 249 .adap_log_addr = cros_ec_cec_set_log_addr, 250 .adap_transmit = cros_ec_cec_transmit, 251 }; 252 253 #ifdef CONFIG_PM_SLEEP 254 static int cros_ec_cec_suspend(struct device *dev) 255 { 256 struct platform_device *pdev = to_platform_device(dev); 257 struct cros_ec_cec *cros_ec_cec = dev_get_drvdata(&pdev->dev); 258 259 if (device_may_wakeup(dev)) 260 enable_irq_wake(cros_ec_cec->cros_ec->irq); 261 262 return 0; 263 } 264 265 static int cros_ec_cec_resume(struct device *dev) 266 { 267 struct platform_device *pdev = to_platform_device(dev); 268 struct cros_ec_cec *cros_ec_cec = dev_get_drvdata(&pdev->dev); 269 270 if (device_may_wakeup(dev)) 271 disable_irq_wake(cros_ec_cec->cros_ec->irq); 272 273 return 0; 274 } 275 #endif 276 277 static SIMPLE_DEV_PM_OPS(cros_ec_cec_pm_ops, 278 cros_ec_cec_suspend, cros_ec_cec_resume); 279 280 #if IS_ENABLED(CONFIG_PCI) && IS_ENABLED(CONFIG_DMI) 281 282 /* 283 * Specify the DRM device name handling the HDMI output and the HDMI connector 284 * corresponding to each CEC port. The order of connectors must match the order 285 * in the EC (first connector is EC port 0, ...), and the number of connectors 286 * must match the number of ports in the EC (which can be queried using the 287 * EC_CMD_CEC_PORT_COUNT host command). 288 */ 289 290 struct cec_dmi_match { 291 const char *sys_vendor; 292 const char *product_name; 293 const char *devname; 294 const char *const *conns; 295 }; 296 297 static const char *const fizz_conns[] = { "Port B", NULL }; 298 static const char *const dibbi_conns[] = { "Port D", "Port B", NULL }; 299 static const char *const constitution_conns[] = { "Port B", "Port A", NULL }; 300 static const char *const boxy_conns[] = { "Port D", NULL }; 301 302 static const struct cec_dmi_match cec_dmi_match_table[] = { 303 /* Google Fizz */ 304 { "Google", "Fizz", "0000:00:02.0", fizz_conns }, 305 /* Google Brask */ 306 { "Google", "Brask", "0000:00:02.0", fizz_conns }, 307 /* Google Moli */ 308 { "Google", "Moli", "0000:00:02.0", fizz_conns }, 309 /* Google Kinox */ 310 { "Google", "Kinox", "0000:00:02.0", fizz_conns }, 311 /* Google Kuldax */ 312 { "Google", "Kuldax", "0000:00:02.0", fizz_conns }, 313 /* Google Aurash */ 314 { "Google", "Aurash", "0000:00:02.0", fizz_conns }, 315 /* Google Gladios */ 316 { "Google", "Gladios", "0000:00:02.0", fizz_conns }, 317 /* Google Lisbon */ 318 { "Google", "Lisbon", "0000:00:02.0", fizz_conns }, 319 /* Google Dibbi */ 320 { "Google", "Dibbi", "0000:00:02.0", dibbi_conns }, 321 /* Google Constitution */ 322 { "Google", "Constitution", "0000:00:02.0", constitution_conns }, 323 /* Google Boxy */ 324 { "Google", "Boxy", "0000:00:02.0", boxy_conns }, 325 }; 326 327 static struct device *cros_ec_cec_find_hdmi_dev(struct device *dev, 328 const char * const **conns) 329 { 330 int i; 331 332 for (i = 0 ; i < ARRAY_SIZE(cec_dmi_match_table) ; ++i) { 333 const struct cec_dmi_match *m = &cec_dmi_match_table[i]; 334 335 if (dmi_match(DMI_SYS_VENDOR, m->sys_vendor) && 336 dmi_match(DMI_PRODUCT_NAME, m->product_name)) { 337 struct device *d; 338 339 /* Find the device, bail out if not yet registered */ 340 d = bus_find_device_by_name(&pci_bus_type, NULL, 341 m->devname); 342 if (!d) 343 return ERR_PTR(-EPROBE_DEFER); 344 put_device(d); 345 *conns = m->conns; 346 return d; 347 } 348 } 349 350 /* Hardware support must be added in the cec_dmi_match_table */ 351 dev_warn(dev, "CEC notifier not configured for this hardware\n"); 352 353 return ERR_PTR(-ENODEV); 354 } 355 356 #else 357 358 static struct device *cros_ec_cec_find_hdmi_dev(struct device *dev, 359 const char * const **conns) 360 { 361 return ERR_PTR(-ENODEV); 362 } 363 364 #endif 365 366 static int cros_ec_cec_get_num_ports(struct cros_ec_cec *cros_ec_cec) 367 { 368 struct ec_response_cec_port_count response; 369 int ret; 370 371 ret = cros_ec_cmd(cros_ec_cec->cros_ec, 0, EC_CMD_CEC_PORT_COUNT, NULL, 372 0, &response, sizeof(response)); 373 if (ret < 0) { 374 /* 375 * Old EC firmware only supports one port and does not support 376 * the port count command, so fall back to assuming one port. 377 */ 378 cros_ec_cec->num_ports = 1; 379 return 0; 380 } 381 382 if (response.port_count == 0) { 383 dev_err(cros_ec_cec->cros_ec->dev, 384 "EC reports 0 CEC ports\n"); 385 return -ENODEV; 386 } 387 388 if (response.port_count > EC_CEC_MAX_PORTS) { 389 dev_err(cros_ec_cec->cros_ec->dev, 390 "EC reports too many ports: %d\n", response.port_count); 391 return -EINVAL; 392 } 393 394 cros_ec_cec->num_ports = response.port_count; 395 return 0; 396 } 397 398 static int cros_ec_cec_get_write_cmd_version(struct cros_ec_cec *cros_ec_cec) 399 { 400 struct cros_ec_device *cros_ec = cros_ec_cec->cros_ec; 401 struct ec_params_get_cmd_versions_v1 params = { 402 .cmd = EC_CMD_CEC_WRITE_MSG, 403 }; 404 struct ec_response_get_cmd_versions response; 405 int ret; 406 407 ret = cros_ec_cmd(cros_ec, 1, EC_CMD_GET_CMD_VERSIONS, ¶ms, 408 sizeof(params), &response, sizeof(response)); 409 if (ret < 0) { 410 dev_err(cros_ec->dev, 411 "error getting CEC write command version: %d\n", ret); 412 return ret; 413 } 414 415 if (response.version_mask & EC_VER_MASK(1)) { 416 cros_ec_cec->write_cmd_version = 1; 417 } else { 418 if (cros_ec_cec->num_ports != 1) { 419 dev_err(cros_ec->dev, 420 "v0 write command only supports 1 port, %d reported\n", 421 cros_ec_cec->num_ports); 422 return -EINVAL; 423 } 424 cros_ec_cec->write_cmd_version = 0; 425 } 426 427 return 0; 428 } 429 430 static int cros_ec_cec_init_port(struct device *dev, 431 struct cros_ec_cec *cros_ec_cec, 432 int port_num, struct device *hdmi_dev, 433 const char * const *conns) 434 { 435 struct cros_ec_cec_port *port; 436 int ret; 437 438 port = devm_kzalloc(dev, sizeof(*port), GFP_KERNEL); 439 if (!port) 440 return -ENOMEM; 441 442 port->cros_ec_cec = cros_ec_cec; 443 port->port_num = port_num; 444 445 port->adap = cec_allocate_adapter(&cros_ec_cec_ops, port, DRV_NAME, 446 CEC_CAP_DEFAULTS | 447 CEC_CAP_CONNECTOR_INFO, 1); 448 if (IS_ERR(port->adap)) 449 return PTR_ERR(port->adap); 450 451 if (!conns[port_num]) { 452 dev_err(dev, "no conn for port %d\n", port_num); 453 ret = -ENODEV; 454 goto out_probe_adapter; 455 } 456 457 port->notify = cec_notifier_cec_adap_register(hdmi_dev, conns[port_num], 458 port->adap); 459 if (!port->notify) { 460 ret = -ENOMEM; 461 goto out_probe_adapter; 462 } 463 464 ret = cec_register_adapter(port->adap, dev); 465 if (ret < 0) 466 goto out_probe_notify; 467 468 cros_ec_cec->ports[port_num] = port; 469 470 return 0; 471 472 out_probe_notify: 473 cec_notifier_cec_adap_unregister(port->notify, port->adap); 474 out_probe_adapter: 475 cec_delete_adapter(port->adap); 476 return ret; 477 } 478 479 static int cros_ec_cec_probe(struct platform_device *pdev) 480 { 481 struct cros_ec_dev *ec_dev = dev_get_drvdata(pdev->dev.parent); 482 struct cros_ec_device *cros_ec = ec_dev->ec_dev; 483 struct cros_ec_cec *cros_ec_cec; 484 struct cros_ec_cec_port *port; 485 struct device *hdmi_dev; 486 const char * const *conns = NULL; 487 int ret; 488 489 hdmi_dev = cros_ec_cec_find_hdmi_dev(&pdev->dev, &conns); 490 if (IS_ERR(hdmi_dev)) 491 return PTR_ERR(hdmi_dev); 492 493 cros_ec_cec = devm_kzalloc(&pdev->dev, sizeof(*cros_ec_cec), 494 GFP_KERNEL); 495 if (!cros_ec_cec) 496 return -ENOMEM; 497 498 platform_set_drvdata(pdev, cros_ec_cec); 499 cros_ec_cec->cros_ec = cros_ec; 500 501 device_init_wakeup(&pdev->dev, 1); 502 503 ret = cros_ec_cec_get_num_ports(cros_ec_cec); 504 if (ret) 505 return ret; 506 507 ret = cros_ec_cec_get_write_cmd_version(cros_ec_cec); 508 if (ret) 509 return ret; 510 511 for (int i = 0; i < cros_ec_cec->num_ports; i++) { 512 ret = cros_ec_cec_init_port(&pdev->dev, cros_ec_cec, i, 513 hdmi_dev, conns); 514 if (ret) 515 goto unregister_ports; 516 } 517 518 /* Get CEC events from the EC. */ 519 cros_ec_cec->notifier.notifier_call = cros_ec_cec_event; 520 ret = blocking_notifier_chain_register(&cros_ec->event_notifier, 521 &cros_ec_cec->notifier); 522 if (ret) { 523 dev_err(&pdev->dev, "failed to register notifier\n"); 524 goto unregister_ports; 525 } 526 527 return 0; 528 529 unregister_ports: 530 /* 531 * Unregister any adapters which have been registered. We don't add the 532 * port to the array until the adapter has been registered successfully, 533 * so any non-NULL ports must have been registered. 534 */ 535 for (int i = 0; i < cros_ec_cec->num_ports; i++) { 536 port = cros_ec_cec->ports[i]; 537 if (!port) 538 break; 539 cec_notifier_cec_adap_unregister(port->notify, port->adap); 540 cec_unregister_adapter(port->adap); 541 } 542 return ret; 543 } 544 545 static void cros_ec_cec_remove(struct platform_device *pdev) 546 { 547 struct cros_ec_cec *cros_ec_cec = platform_get_drvdata(pdev); 548 struct device *dev = &pdev->dev; 549 struct cros_ec_cec_port *port; 550 int ret; 551 552 /* 553 * blocking_notifier_chain_unregister() only fails if the notifier isn't 554 * in the list. We know it was added to it by .probe(), so there should 555 * be no need for error checking. Be cautious and still check. 556 */ 557 ret = blocking_notifier_chain_unregister( 558 &cros_ec_cec->cros_ec->event_notifier, 559 &cros_ec_cec->notifier); 560 if (ret) 561 dev_err(dev, "failed to unregister notifier\n"); 562 563 for (int i = 0; i < cros_ec_cec->num_ports; i++) { 564 port = cros_ec_cec->ports[i]; 565 cec_notifier_cec_adap_unregister(port->notify, port->adap); 566 cec_unregister_adapter(port->adap); 567 } 568 } 569 570 static struct platform_driver cros_ec_cec_driver = { 571 .probe = cros_ec_cec_probe, 572 .remove_new = cros_ec_cec_remove, 573 .driver = { 574 .name = DRV_NAME, 575 .pm = &cros_ec_cec_pm_ops, 576 }, 577 }; 578 579 module_platform_driver(cros_ec_cec_driver); 580 581 MODULE_DESCRIPTION("CEC driver for ChromeOS ECs"); 582 MODULE_AUTHOR("Neil Armstrong <narmstrong@baylibre.com>"); 583 MODULE_LICENSE("GPL"); 584 MODULE_ALIAS("platform:" DRV_NAME); 585