1// SPDX-License-Identifier: GPL-2.0
   2/*
   3 * SVC Greybus driver.
   4 *
   5 * Copyright 2015 Google Inc.
   6 * Copyright 2015 Linaro Ltd.
   7 */
   8
   9#include <linux/debugfs.h>
  10#include <linux/workqueue.h>
  11#include <linux/greybus.h>
  12
  13#define SVC_INTF_EJECT_TIMEOUT		9000
  14#define SVC_INTF_ACTIVATE_TIMEOUT	6000
  15#define SVC_INTF_RESUME_TIMEOUT		3000
  16
  17struct gb_svc_deferred_request {
  18	struct work_struct work;
  19	struct gb_operation *operation;
  20};
  21
  22static int gb_svc_queue_deferred_request(struct gb_operation *operation);
  23
  24static ssize_t endo_id_show(struct device *dev,
  25			    struct device_attribute *attr, char *buf)
  26{
  27	struct gb_svc *svc = to_gb_svc(dev);
  28
  29	return sprintf(buf, "0x%04x\n", svc->endo_id);
  30}
  31static DEVICE_ATTR_RO(endo_id);
  32
  33static ssize_t ap_intf_id_show(struct device *dev,
  34			       struct device_attribute *attr, char *buf)
  35{
  36	struct gb_svc *svc = to_gb_svc(dev);
  37
  38	return sprintf(buf, "%u\n", svc->ap_intf_id);
  39}
  40static DEVICE_ATTR_RO(ap_intf_id);
  41
  42// FIXME
  43// This is a hack, we need to do this "right" and clean the interface up
  44// properly, not just forcibly yank the thing out of the system and hope for the
  45// best.  But for now, people want their modules to come out without having to
  46// throw the thing to the ground or get out a screwdriver.
  47static ssize_t intf_eject_store(struct device *dev,
  48				struct device_attribute *attr, const char *buf,
  49				size_t len)
  50{
  51	struct gb_svc *svc = to_gb_svc(dev);
  52	unsigned short intf_id;
  53	int ret;
  54
  55	ret = kstrtou16(buf, 10, &intf_id);
  56	if (ret < 0)
  57		return ret;
  58
  59	dev_warn(dev, "Forcibly trying to eject interface %d\n", intf_id);
  60
  61	ret = gb_svc_intf_eject(svc, intf_id);
  62	if (ret < 0)
  63		return ret;
  64
  65	return len;
  66}
  67static DEVICE_ATTR_WO(intf_eject);
  68
  69static ssize_t watchdog_show(struct device *dev, struct device_attribute *attr,
  70			     char *buf)
  71{
  72	struct gb_svc *svc = to_gb_svc(dev);
  73
  74	return sprintf(buf, "%s\n",
  75		       gb_svc_watchdog_enabled(svc) ? "enabled" : "disabled");
  76}
  77
  78static ssize_t watchdog_store(struct device *dev,
  79			      struct device_attribute *attr, const char *buf,
  80			      size_t len)
  81{
  82	struct gb_svc *svc = to_gb_svc(dev);
  83	int retval;
  84	bool user_request;
  85
  86	retval = strtobool(buf, &user_request);
  87	if (retval)
  88		return retval;
  89
  90	if (user_request)
  91		retval = gb_svc_watchdog_enable(svc);
  92	else
  93		retval = gb_svc_watchdog_disable(svc);
  94	if (retval)
  95		return retval;
  96	return len;
  97}
  98static DEVICE_ATTR_RW(watchdog);
  99
 100static ssize_t watchdog_action_show(struct device *dev,
 101				    struct device_attribute *attr, char *buf)
 102{
 103	struct gb_svc *svc = to_gb_svc(dev);
 104
 105	if (svc->action == GB_SVC_WATCHDOG_BITE_PANIC_KERNEL)
 106		return sprintf(buf, "panic\n");
 107	else if (svc->action == GB_SVC_WATCHDOG_BITE_RESET_UNIPRO)
 108		return sprintf(buf, "reset\n");
 109
 110	return -EINVAL;
 111}
 112
 113static ssize_t watchdog_action_store(struct device *dev,
 114				     struct device_attribute *attr,
 115				     const char *buf, size_t len)
 116{
 117	struct gb_svc *svc = to_gb_svc(dev);
 118
 119	if (sysfs_streq(buf, "panic"))
 120		svc->action = GB_SVC_WATCHDOG_BITE_PANIC_KERNEL;
 121	else if (sysfs_streq(buf, "reset"))
 122		svc->action = GB_SVC_WATCHDOG_BITE_RESET_UNIPRO;
 123	else
 124		return -EINVAL;
 125
 126	return len;
 127}
 128static DEVICE_ATTR_RW(watchdog_action);
 129
 130static int gb_svc_pwrmon_rail_count_get(struct gb_svc *svc, u8 *value)
 131{
 132	struct gb_svc_pwrmon_rail_count_get_response response;
 133	int ret;
 134
 135	ret = gb_operation_sync(svc->connection,
 136				GB_SVC_TYPE_PWRMON_RAIL_COUNT_GET, NULL, 0,
 137				&response, sizeof(response));
 138	if (ret) {
 139		dev_err(&svc->dev, "failed to get rail count: %d\n", ret);
 140		return ret;
 141	}
 142
 143	*value = response.rail_count;
 144
 145	return 0;
 146}
 147
 148static int gb_svc_pwrmon_rail_names_get(struct gb_svc *svc,
 149		struct gb_svc_pwrmon_rail_names_get_response *response,
 150		size_t bufsize)
 151{
 152	int ret;
 153
 154	ret = gb_operation_sync(svc->connection,
 155				GB_SVC_TYPE_PWRMON_RAIL_NAMES_GET, NULL, 0,
 156				response, bufsize);
 157	if (ret) {
 158		dev_err(&svc->dev, "failed to get rail names: %d\n", ret);
 159		return ret;
 160	}
 161
 162	if (response->status != GB_SVC_OP_SUCCESS) {
 163		dev_err(&svc->dev,
 164			"SVC error while getting rail names: %u\n",
 165			response->status);
 166		return -EREMOTEIO;
 167	}
 168
 169	return 0;
 170}
 171
 172static int gb_svc_pwrmon_sample_get(struct gb_svc *svc, u8 rail_id,
 173				    u8 measurement_type, u32 *value)
 174{
 175	struct gb_svc_pwrmon_sample_get_request request;
 176	struct gb_svc_pwrmon_sample_get_response response;
 177	int ret;
 178
 179	request.rail_id = rail_id;
 180	request.measurement_type = measurement_type;
 181
 182	ret = gb_operation_sync(svc->connection, GB_SVC_TYPE_PWRMON_SAMPLE_GET,
 183				&request, sizeof(request),
 184				&response, sizeof(response));
 185	if (ret) {
 186		dev_err(&svc->dev, "failed to get rail sample: %d\n", ret);
 187		return ret;
 188	}
 189
 190	if (response.result) {
 191		dev_err(&svc->dev,
 192			"UniPro error while getting rail power sample (%d %d): %d\n",
 193			rail_id, measurement_type, response.result);
 194		switch (response.result) {
 195		case GB_SVC_PWRMON_GET_SAMPLE_INVAL:
 196			return -EINVAL;
 197		case GB_SVC_PWRMON_GET_SAMPLE_NOSUPP:
 198			return -ENOMSG;
 199		default:
 200			return -EREMOTEIO;
 201		}
 202	}
 203
 204	*value = le32_to_cpu(response.measurement);
 205
 206	return 0;
 207}
 208
 209int gb_svc_pwrmon_intf_sample_get(struct gb_svc *svc, u8 intf_id,
 210				  u8 measurement_type, u32 *value)
 211{
 212	struct gb_svc_pwrmon_intf_sample_get_request request;
 213	struct gb_svc_pwrmon_intf_sample_get_response response;
 214	int ret;
 215
 216	request.intf_id = intf_id;
 217	request.measurement_type = measurement_type;
 218
 219	ret = gb_operation_sync(svc->connection,
 220				GB_SVC_TYPE_PWRMON_INTF_SAMPLE_GET,
 221				&request, sizeof(request),
 222				&response, sizeof(response));
 223	if (ret) {
 224		dev_err(&svc->dev, "failed to get intf sample: %d\n", ret);
 225		return ret;
 226	}
 227
 228	if (response.result) {
 229		dev_err(&svc->dev,
 230			"UniPro error while getting intf power sample (%d %d): %d\n",
 231			intf_id, measurement_type, response.result);
 232		switch (response.result) {
 233		case GB_SVC_PWRMON_GET_SAMPLE_INVAL:
 234			return -EINVAL;
 235		case GB_SVC_PWRMON_GET_SAMPLE_NOSUPP:
 236			return -ENOMSG;
 237		default:
 238			return -EREMOTEIO;
 239		}
 240	}
 241
 242	*value = le32_to_cpu(response.measurement);
 243
 244	return 0;
 245}
 246
 247static struct attribute *svc_attrs[] = {
 248	&dev_attr_endo_id.attr,
 249	&dev_attr_ap_intf_id.attr,
 250	&dev_attr_intf_eject.attr,
 251	&dev_attr_watchdog.attr,
 252	&dev_attr_watchdog_action.attr,
 253	NULL,
 254};
 255ATTRIBUTE_GROUPS(svc);
 256
 257int gb_svc_intf_device_id(struct gb_svc *svc, u8 intf_id, u8 device_id)
 258{
 259	struct gb_svc_intf_device_id_request request;
 260
 261	request.intf_id = intf_id;
 262	request.device_id = device_id;
 263
 264	return gb_operation_sync(svc->connection, GB_SVC_TYPE_INTF_DEVICE_ID,
 265				 &request, sizeof(request), NULL, 0);
 266}
 267
 268int gb_svc_intf_eject(struct gb_svc *svc, u8 intf_id)
 269{
 270	struct gb_svc_intf_eject_request request;
 271	int ret;
 272
 273	request.intf_id = intf_id;
 274
 275	/*
 276	 * The pulse width for module release in svc is long so we need to
 277	 * increase the timeout so the operation will not return to soon.
 278	 */
 279	ret = gb_operation_sync_timeout(svc->connection,
 280					GB_SVC_TYPE_INTF_EJECT, &request,
 281					sizeof(request), NULL, 0,
 282					SVC_INTF_EJECT_TIMEOUT);
 283	if (ret) {
 284		dev_err(&svc->dev, "failed to eject interface %u\n", intf_id);
 285		return ret;
 286	}
 287
 288	return 0;
 289}
 290
 291int gb_svc_intf_vsys_set(struct gb_svc *svc, u8 intf_id, bool enable)
 292{
 293	struct gb_svc_intf_vsys_request request;
 294	struct gb_svc_intf_vsys_response response;
 295	int type, ret;
 296
 297	request.intf_id = intf_id;
 298
 299	if (enable)
 300		type = GB_SVC_TYPE_INTF_VSYS_ENABLE;
 301	else
 302		type = GB_SVC_TYPE_INTF_VSYS_DISABLE;
 303
 304	ret = gb_operation_sync(svc->connection, type,
 305				&request, sizeof(request),
 306				&response, sizeof(response));
 307	if (ret < 0)
 308		return ret;
 309	if (response.result_code != GB_SVC_INTF_VSYS_OK)
 310		return -EREMOTEIO;
 311	return 0;
 312}
 313
 314int gb_svc_intf_refclk_set(struct gb_svc *svc, u8 intf_id, bool enable)
 315{
 316	struct gb_svc_intf_refclk_request request;
 317	struct gb_svc_intf_refclk_response response;
 318	int type, ret;
 319
 320	request.intf_id = intf_id;
 321
 322	if (enable)
 323		type = GB_SVC_TYPE_INTF_REFCLK_ENABLE;
 324	else
 325		type = GB_SVC_TYPE_INTF_REFCLK_DISABLE;
 326
 327	ret = gb_operation_sync(svc->connection, type,
 328				&request, sizeof(request),
 329				&response, sizeof(response));
 330	if (ret < 0)
 331		return ret;
 332	if (response.result_code != GB_SVC_INTF_REFCLK_OK)
 333		return -EREMOTEIO;
 334	return 0;
 335}
 336
 337int gb_svc_intf_unipro_set(struct gb_svc *svc, u8 intf_id, bool enable)
 338{
 339	struct gb_svc_intf_unipro_request request;
 340	struct gb_svc_intf_unipro_response response;
 341	int type, ret;
 342
 343	request.intf_id = intf_id;
 344
 345	if (enable)
 346		type = GB_SVC_TYPE_INTF_UNIPRO_ENABLE;
 347	else
 348		type = GB_SVC_TYPE_INTF_UNIPRO_DISABLE;
 349
 350	ret = gb_operation_sync(svc->connection, type,
 351				&request, sizeof(request),
 352				&response, sizeof(response));
 353	if (ret < 0)
 354		return ret;
 355	if (response.result_code != GB_SVC_INTF_UNIPRO_OK)
 356		return -EREMOTEIO;
 357	return 0;
 358}
 359
 360int gb_svc_intf_activate(struct gb_svc *svc, u8 intf_id, u8 *intf_type)
 361{
 362	struct gb_svc_intf_activate_request request;
 363	struct gb_svc_intf_activate_response response;
 364	int ret;
 365
 366	request.intf_id = intf_id;
 367
 368	ret = gb_operation_sync_timeout(svc->connection,
 369					GB_SVC_TYPE_INTF_ACTIVATE,
 370					&request, sizeof(request),
 371					&response, sizeof(response),
 372					SVC_INTF_ACTIVATE_TIMEOUT);
 373	if (ret < 0)
 374		return ret;
 375	if (response.status != GB_SVC_OP_SUCCESS) {
 376		dev_err(&svc->dev, "failed to activate interface %u: %u\n",
 377			intf_id, response.status);
 378		return -EREMOTEIO;
 379	}
 380
 381	*intf_type = response.intf_type;
 382
 383	return 0;
 384}
 385
 386int gb_svc_intf_resume(struct gb_svc *svc, u8 intf_id)
 387{
 388	struct gb_svc_intf_resume_request request;
 389	struct gb_svc_intf_resume_response response;
 390	int ret;
 391
 392	request.intf_id = intf_id;
 393
 394	ret = gb_operation_sync_timeout(svc->connection,
 395					GB_SVC_TYPE_INTF_RESUME,
 396					&request, sizeof(request),
 397					&response, sizeof(response),
 398					SVC_INTF_RESUME_TIMEOUT);
 399	if (ret < 0) {
 400		dev_err(&svc->dev, "failed to send interface resume %u: %d\n",
 401			intf_id, ret);
 402		return ret;
 403	}
 404
 405	if (response.status != GB_SVC_OP_SUCCESS) {
 406		dev_err(&svc->dev, "failed to resume interface %u: %u\n",
 407			intf_id, response.status);
 408		return -EREMOTEIO;
 409	}
 410
 411	return 0;
 412}
 413
 414int gb_svc_dme_peer_get(struct gb_svc *svc, u8 intf_id, u16 attr, u16 selector,
 415			u32 *value)
 416{
 417	struct gb_svc_dme_peer_get_request request;
 418	struct gb_svc_dme_peer_get_response response;
 419	u16 result;
 420	int ret;
 421
 422	request.intf_id = intf_id;
 423	request.attr = cpu_to_le16(attr);
 424	request.selector = cpu_to_le16(selector);
 425
 426	ret = gb_operation_sync(svc->connection, GB_SVC_TYPE_DME_PEER_GET,
 427				&request, sizeof(request),
 428				&response, sizeof(response));
 429	if (ret) {
 430		dev_err(&svc->dev, "failed to get DME attribute (%u 0x%04x %u): %d\n",
 431			intf_id, attr, selector, ret);
 432		return ret;
 433	}
 434
 435	result = le16_to_cpu(response.result_code);
 436	if (result) {
 437		dev_err(&svc->dev, "UniPro error while getting DME attribute (%u 0x%04x %u): %u\n",
 438			intf_id, attr, selector, result);
 439		return -EREMOTEIO;
 440	}
 441
 442	if (value)
 443		*value = le32_to_cpu(response.attr_value);
 444
 445	return 0;
 446}
 447
 448int gb_svc_dme_peer_set(struct gb_svc *svc, u8 intf_id, u16 attr, u16 selector,
 449			u32 value)
 450{
 451	struct gb_svc_dme_peer_set_request request;
 452	struct gb_svc_dme_peer_set_response response;
 453	u16 result;
 454	int ret;
 455
 456	request.intf_id = intf_id;
 457	request.attr = cpu_to_le16(attr);
 458	request.selector = cpu_to_le16(selector);
 459	request.value = cpu_to_le32(value);
 460
 461	ret = gb_operation_sync(svc->connection, GB_SVC_TYPE_DME_PEER_SET,
 462				&request, sizeof(request),
 463				&response, sizeof(response));
 464	if (ret) {
 465		dev_err(&svc->dev, "failed to set DME attribute (%u 0x%04x %u %u): %d\n",
 466			intf_id, attr, selector, value, ret);
 467		return ret;
 468	}
 469
 470	result = le16_to_cpu(response.result_code);
 471	if (result) {
 472		dev_err(&svc->dev, "UniPro error while setting DME attribute (%u 0x%04x %u %u): %u\n",
 473			intf_id, attr, selector, value, result);
 474		return -EREMOTEIO;
 475	}
 476
 477	return 0;
 478}
 479
 480int gb_svc_connection_create(struct gb_svc *svc,
 481			     u8 intf1_id, u16 cport1_id,
 482			     u8 intf2_id, u16 cport2_id,
 483			     u8 cport_flags)
 484{
 485	struct gb_svc_conn_create_request request;
 486
 487	request.intf1_id = intf1_id;
 488	request.cport1_id = cpu_to_le16(cport1_id);
 489	request.intf2_id = intf2_id;
 490	request.cport2_id = cpu_to_le16(cport2_id);
 491	request.tc = 0;		/* TC0 */
 492	request.flags = cport_flags;
 493
 494	return gb_operation_sync(svc->connection, GB_SVC_TYPE_CONN_CREATE,
 495				 &request, sizeof(request), NULL, 0);
 496}
 497
 498void gb_svc_connection_destroy(struct gb_svc *svc, u8 intf1_id, u16 cport1_id,
 499			       u8 intf2_id, u16 cport2_id)
 500{
 501	struct gb_svc_conn_destroy_request request;
 502	struct gb_connection *connection = svc->connection;
 503	int ret;
 504
 505	request.intf1_id = intf1_id;
 506	request.cport1_id = cpu_to_le16(cport1_id);
 507	request.intf2_id = intf2_id;
 508	request.cport2_id = cpu_to_le16(cport2_id);
 509
 510	ret = gb_operation_sync(connection, GB_SVC_TYPE_CONN_DESTROY,
 511				&request, sizeof(request), NULL, 0);
 512	if (ret) {
 513		dev_err(&svc->dev, "failed to destroy connection (%u:%u %u:%u): %d\n",
 514			intf1_id, cport1_id, intf2_id, cport2_id, ret);
 515	}
 516}
 517
 518/* Creates bi-directional routes between the devices */
 519int gb_svc_route_create(struct gb_svc *svc, u8 intf1_id, u8 dev1_id,
 520			u8 intf2_id, u8 dev2_id)
 521{
 522	struct gb_svc_route_create_request request;
 523
 524	request.intf1_id = intf1_id;
 525	request.dev1_id = dev1_id;
 526	request.intf2_id = intf2_id;
 527	request.dev2_id = dev2_id;
 528
 529	return gb_operation_sync(svc->connection, GB_SVC_TYPE_ROUTE_CREATE,
 530				 &request, sizeof(request), NULL, 0);
 531}
 532
 533/* Destroys bi-directional routes between the devices */
 534void gb_svc_route_destroy(struct gb_svc *svc, u8 intf1_id, u8 intf2_id)
 535{
 536	struct gb_svc_route_destroy_request request;
 537	int ret;
 538
 539	request.intf1_id = intf1_id;
 540	request.intf2_id = intf2_id;
 541
 542	ret = gb_operation_sync(svc->connection, GB_SVC_TYPE_ROUTE_DESTROY,
 543				&request, sizeof(request), NULL, 0);
 544	if (ret) {
 545		dev_err(&svc->dev, "failed to destroy route (%u %u): %d\n",
 546			intf1_id, intf2_id, ret);
 547	}
 548}
 549
 550int gb_svc_intf_set_power_mode(struct gb_svc *svc, u8 intf_id, u8 hs_series,
 551			       u8 tx_mode, u8 tx_gear, u8 tx_nlanes,
 552			       u8 tx_amplitude, u8 tx_hs_equalizer,
 553			       u8 rx_mode, u8 rx_gear, u8 rx_nlanes,
 554			       u8 flags, u32 quirks,
 555			       struct gb_svc_l2_timer_cfg *local,
 556			       struct gb_svc_l2_timer_cfg *remote)
 557{
 558	struct gb_svc_intf_set_pwrm_request request;
 559	struct gb_svc_intf_set_pwrm_response response;
 560	int ret;
 561	u16 result_code;
 562
 563	memset(&request, 0, sizeof(request));
 564
 565	request.intf_id = intf_id;
 566	request.hs_series = hs_series;
 567	request.tx_mode = tx_mode;
 568	request.tx_gear = tx_gear;
 569	request.tx_nlanes = tx_nlanes;
 570	request.tx_amplitude = tx_amplitude;
 571	request.tx_hs_equalizer = tx_hs_equalizer;
 572	request.rx_mode = rx_mode;
 573	request.rx_gear = rx_gear;
 574	request.rx_nlanes = rx_nlanes;
 575	request.flags = flags;
 576	request.quirks = cpu_to_le32(quirks);
 577	if (local)
 578		request.local_l2timerdata = *local;
 579	if (remote)
 580		request.remote_l2timerdata = *remote;
 581
 582	ret = gb_operation_sync(svc->connection, GB_SVC_TYPE_INTF_SET_PWRM,
 583				&request, sizeof(request),
 584				&response, sizeof(response));
 585	if (ret < 0)
 586		return ret;
 587
 588	result_code = response.result_code;
 589	if (result_code != GB_SVC_SETPWRM_PWR_LOCAL) {
 590		dev_err(&svc->dev, "set power mode = %d\n", result_code);
 591		return -EIO;
 592	}
 593
 594	return 0;
 595}
 596EXPORT_SYMBOL_GPL(gb_svc_intf_set_power_mode);
 597
 598int gb_svc_intf_set_power_mode_hibernate(struct gb_svc *svc, u8 intf_id)
 599{
 600	struct gb_svc_intf_set_pwrm_request request;
 601	struct gb_svc_intf_set_pwrm_response response;
 602	int ret;
 603	u16 result_code;
 604
 605	memset(&request, 0, sizeof(request));
 606
 607	request.intf_id = intf_id;
 608	request.hs_series = GB_SVC_UNIPRO_HS_SERIES_A;
 609	request.tx_mode = GB_SVC_UNIPRO_HIBERNATE_MODE;
 610	request.rx_mode = GB_SVC_UNIPRO_HIBERNATE_MODE;
 611
 612	ret = gb_operation_sync(svc->connection, GB_SVC_TYPE_INTF_SET_PWRM,
 613				&request, sizeof(request),
 614				&response, sizeof(response));
 615	if (ret < 0) {
 616		dev_err(&svc->dev,
 617			"failed to send set power mode operation to interface %u: %d\n",
 618			intf_id, ret);
 619		return ret;
 620	}
 621
 622	result_code = response.result_code;
 623	if (result_code != GB_SVC_SETPWRM_PWR_OK) {
 624		dev_err(&svc->dev,
 625			"failed to hibernate the link for interface %u: %u\n",
 626			intf_id, result_code);
 627		return -EIO;
 628	}
 629
 630	return 0;
 631}
 632
 633int gb_svc_ping(struct gb_svc *svc)
 634{
 635	return gb_operation_sync_timeout(svc->connection, GB_SVC_TYPE_PING,
 636					 NULL, 0, NULL, 0,
 637					 GB_OPERATION_TIMEOUT_DEFAULT * 2);
 638}
 639
 640static int gb_svc_version_request(struct gb_operation *op)
 641{
 642	struct gb_connection *connection = op->connection;
 643	struct gb_svc *svc = gb_connection_get_data(connection);
 644	struct gb_svc_version_request *request;
 645	struct gb_svc_version_response *response;
 646
 647	if (op->request->payload_size < sizeof(*request)) {
 648		dev_err(&svc->dev, "short version request (%zu < %zu)\n",
 649			op->request->payload_size,
 650			sizeof(*request));
 651		return -EINVAL;
 652	}
 653
 654	request = op->request->payload;
 655
 656	if (request->major > GB_SVC_VERSION_MAJOR) {
 657		dev_warn(&svc->dev, "unsupported major version (%u > %u)\n",
 658			 request->major, GB_SVC_VERSION_MAJOR);
 659		return -ENOTSUPP;
 660	}
 661
 662	svc->protocol_major = request->major;
 663	svc->protocol_minor = request->minor;
 664
 665	if (!gb_operation_response_alloc(op, sizeof(*response), GFP_KERNEL))
 666		return -ENOMEM;
 667
 668	response = op->response->payload;
 669	response->major = svc->protocol_major;
 670	response->minor = svc->protocol_minor;
 671
 672	return 0;
 673}
 674
 675static ssize_t pwr_debugfs_voltage_read(struct file *file, char __user *buf,
 676					size_t len, loff_t *offset)
 677{
 678	struct svc_debugfs_pwrmon_rail *pwrmon_rails =
 679		file_inode(file)->i_private;
 680	struct gb_svc *svc = pwrmon_rails->svc;
 681	int ret, desc;
 682	u32 value;
 683	char buff[16];
 684
 685	ret = gb_svc_pwrmon_sample_get(svc, pwrmon_rails->id,
 686				       GB_SVC_PWRMON_TYPE_VOL, &value);
 687	if (ret) {
 688		dev_err(&svc->dev,
 689			"failed to get voltage sample %u: %d\n",
 690			pwrmon_rails->id, ret);
 691		return ret;
 692	}
 693
 694	desc = scnprintf(buff, sizeof(buff), "%u\n", value);
 695
 696	return simple_read_from_buffer(buf, len, offset, buff, desc);
 697}
 698
 699static ssize_t pwr_debugfs_current_read(struct file *file, char __user *buf,
 700					size_t len, loff_t *offset)
 701{
 702	struct svc_debugfs_pwrmon_rail *pwrmon_rails =
 703		file_inode(file)->i_private;
 704	struct gb_svc *svc = pwrmon_rails->svc;
 705	int ret, desc;
 706	u32 value;
 707	char buff[16];
 708
 709	ret = gb_svc_pwrmon_sample_get(svc, pwrmon_rails->id,
 710				       GB_SVC_PWRMON_TYPE_CURR, &value);
 711	if (ret) {
 712		dev_err(&svc->dev,
 713			"failed to get current sample %u: %d\n",
 714			pwrmon_rails->id, ret);
 715		return ret;
 716	}
 717
 718	desc = scnprintf(buff, sizeof(buff), "%u\n", value);
 719
 720	return simple_read_from_buffer(buf, len, offset, buff, desc);
 721}
 722
 723static ssize_t pwr_debugfs_power_read(struct file *file, char __user *buf,
 724				      size_t len, loff_t *offset)
 725{
 726	struct svc_debugfs_pwrmon_rail *pwrmon_rails =
 727		file_inode(file)->i_private;
 728	struct gb_svc *svc = pwrmon_rails->svc;
 729	int ret, desc;
 730	u32 value;
 731	char buff[16];
 732
 733	ret = gb_svc_pwrmon_sample_get(svc, pwrmon_rails->id,
 734				       GB_SVC_PWRMON_TYPE_PWR, &value);
 735	if (ret) {
 736		dev_err(&svc->dev, "failed to get power sample %u: %d\n",
 737			pwrmon_rails->id, ret);
 738		return ret;
 739	}
 740
 741	desc = scnprintf(buff, sizeof(buff), "%u\n", value);
 742
 743	return simple_read_from_buffer(buf, len, offset, buff, desc);
 744}
 745
 746static const struct file_operations pwrmon_debugfs_voltage_fops = {
 747	.read		= pwr_debugfs_voltage_read,
 748};
 749
 750static const struct file_operations pwrmon_debugfs_current_fops = {
 751	.read		= pwr_debugfs_current_read,
 752};
 753
 754static const struct file_operations pwrmon_debugfs_power_fops = {
 755	.read		= pwr_debugfs_power_read,
 756};
 757
 758static void gb_svc_pwrmon_debugfs_init(struct gb_svc *svc)
 759{
 760	int i;
 761	size_t bufsize;
 762	struct dentry *dent;
 763	struct gb_svc_pwrmon_rail_names_get_response *rail_names;
 764	u8 rail_count;
 765
 766	dent = debugfs_create_dir("pwrmon", svc->debugfs_dentry);
 767	if (IS_ERR_OR_NULL(dent))
 768		return;
 769
 770	if (gb_svc_pwrmon_rail_count_get(svc, &rail_count))
 771		goto err_pwrmon_debugfs;
 772
 773	if (!rail_count || rail_count > GB_SVC_PWRMON_MAX_RAIL_COUNT)
 774		goto err_pwrmon_debugfs;
 775
 776	bufsize = sizeof(*rail_names) +
 777		GB_SVC_PWRMON_RAIL_NAME_BUFSIZE * rail_count;
 778
 779	rail_names = kzalloc(bufsize, GFP_KERNEL);
 780	if (!rail_names)
 781		goto err_pwrmon_debugfs;
 782
 783	svc->pwrmon_rails = kcalloc(rail_count, sizeof(*svc->pwrmon_rails),
 784				    GFP_KERNEL);
 785	if (!svc->pwrmon_rails)
 786		goto err_pwrmon_debugfs_free;
 787
 788	if (gb_svc_pwrmon_rail_names_get(svc, rail_names, bufsize))
 789		goto err_pwrmon_debugfs_free;
 790
 791	for (i = 0; i < rail_count; i++) {
 792		struct dentry *dir;
 793		struct svc_debugfs_pwrmon_rail *rail = &svc->pwrmon_rails[i];
 794		char fname[GB_SVC_PWRMON_RAIL_NAME_BUFSIZE];
 795
 796		snprintf(fname, sizeof(fname), "%s",
 797			 (char *)&rail_names->name[i]);
 798
 799		rail->id = i;
 800		rail->svc = svc;
 801
 802		dir = debugfs_create_dir(fname, dent);
 803		debugfs_create_file("voltage_now", 0444, dir, rail,
 804				    &pwrmon_debugfs_voltage_fops);
 805		debugfs_create_file("current_now", 0444, dir, rail,
 806				    &pwrmon_debugfs_current_fops);
 807		debugfs_create_file("power_now", 0444, dir, rail,
 808				    &pwrmon_debugfs_power_fops);
 809	}
 810
 811	kfree(rail_names);
 812	return;
 813
 814err_pwrmon_debugfs_free:
 815	kfree(rail_names);
 816	kfree(svc->pwrmon_rails);
 817	svc->pwrmon_rails = NULL;
 818
 819err_pwrmon_debugfs:
 820	debugfs_remove(dent);
 821}
 822
 823static void gb_svc_debugfs_init(struct gb_svc *svc)
 824{
 825	svc->debugfs_dentry = debugfs_create_dir(dev_name(&svc->dev),
 826						 gb_debugfs_get());
 827	gb_svc_pwrmon_debugfs_init(svc);
 828}
 829
 830static void gb_svc_debugfs_exit(struct gb_svc *svc)
 831{
 832	debugfs_remove_recursive(svc->debugfs_dentry);
 833	kfree(svc->pwrmon_rails);
 834	svc->pwrmon_rails = NULL;
 835}
 836
 837static int gb_svc_hello(struct gb_operation *op)
 838{
 839	struct gb_connection *connection = op->connection;
 840	struct gb_svc *svc = gb_connection_get_data(connection);
 841	struct gb_svc_hello_request *hello_request;
 842	int ret;
 843
 844	if (op->request->payload_size < sizeof(*hello_request)) {
 845		dev_warn(&svc->dev, "short hello request (%zu < %zu)\n",
 846			 op->request->payload_size,
 847			 sizeof(*hello_request));
 848		return -EINVAL;
 849	}
 850
 851	hello_request = op->request->payload;
 852	svc->endo_id = le16_to_cpu(hello_request->endo_id);
 853	svc->ap_intf_id = hello_request->interface_id;
 854
 855	ret = device_add(&svc->dev);
 856	if (ret) {
 857		dev_err(&svc->dev, "failed to register svc device: %d\n", ret);
 858		return ret;
 859	}
 860
 861	ret = gb_svc_watchdog_create(svc);
 862	if (ret) {
 863		dev_err(&svc->dev, "failed to create watchdog: %d\n", ret);
 864		goto err_unregister_device;
 865	}
 866
 867	gb_svc_debugfs_init(svc);
 868
 869	return gb_svc_queue_deferred_request(op);
 870
 871err_unregister_device:
 872	gb_svc_watchdog_destroy(svc);
 873	device_del(&svc->dev);
 874	return ret;
 875}
 876
 877static struct gb_interface *gb_svc_interface_lookup(struct gb_svc *svc,
 878						    u8 intf_id)
 879{
 880	struct gb_host_device *hd = svc->hd;
 881	struct gb_module *module;
 882	size_t num_interfaces;
 883	u8 module_id;
 884
 885	list_for_each_entry(module, &hd->modules, hd_node) {
 886		module_id = module->module_id;
 887		num_interfaces = module->num_interfaces;
 888
 889		if (intf_id >= module_id &&
 890		    intf_id < module_id + num_interfaces) {
 891			return module->interfaces[intf_id - module_id];
 892		}
 893	}
 894
 895	return NULL;
 896}
 897
 898static struct gb_module *gb_svc_module_lookup(struct gb_svc *svc, u8 module_id)
 899{
 900	struct gb_host_device *hd = svc->hd;
 901	struct gb_module *module;
 902
 903	list_for_each_entry(module, &hd->modules, hd_node) {
 904		if (module->module_id == module_id)
 905			return module;
 906	}
 907
 908	return NULL;
 909}
 910
 911static void gb_svc_process_hello_deferred(struct gb_operation *operation)
 912{
 913	struct gb_connection *connection = operation->connection;
 914	struct gb_svc *svc = gb_connection_get_data(connection);
 915	int ret;
 916
 917	/*
 918	 * XXX This is a hack/work-around to reconfigure the APBridgeA-Switch
 919	 * link to PWM G2, 1 Lane, Slow Auto, so that it has sufficient
 920	 * bandwidth for 3 audio streams plus boot-over-UniPro of a hot-plugged
 921	 * module.
 922	 *
 923	 * The code should be removed once SW-2217, Heuristic for UniPro
 924	 * Power Mode Changes is resolved.
 925	 */
 926	ret = gb_svc_intf_set_power_mode(svc, svc->ap_intf_id,
 927					 GB_SVC_UNIPRO_HS_SERIES_A,
 928					 GB_SVC_UNIPRO_SLOW_AUTO_MODE,
 929					 2, 1,
 930					 GB_SVC_SMALL_AMPLITUDE,
 931					 GB_SVC_NO_DE_EMPHASIS,
 932					 GB_SVC_UNIPRO_SLOW_AUTO_MODE,
 933					 2, 1,
 934					 0, 0,
 935					 NULL, NULL);
 936
 937	if (ret)
 938		dev_warn(&svc->dev,
 939			 "power mode change failed on AP to switch link: %d\n",
 940			 ret);
 941}
 942
 943static void gb_svc_process_module_inserted(struct gb_operation *operation)
 944{
 945	struct gb_svc_module_inserted_request *request;
 946	struct gb_connection *connection = operation->connection;
 947	struct gb_svc *svc = gb_connection_get_data(connection);
 948	struct gb_host_device *hd = svc->hd;
 949	struct gb_module *module;
 950	size_t num_interfaces;
 951	u8 module_id;
 952	u16 flags;
 953	int ret;
 954
 955	/* The request message size has already been verified. */
 956	request = operation->request->payload;
 957	module_id = request->primary_intf_id;
 958	num_interfaces = request->intf_count;
 959	flags = le16_to_cpu(request->flags);
 960
 961	dev_dbg(&svc->dev, "%s - id = %u, num_interfaces = %zu, flags = 0x%04x\n",
 962		__func__, module_id, num_interfaces, flags);
 963
 964	if (flags & GB_SVC_MODULE_INSERTED_FLAG_NO_PRIMARY) {
 965		dev_warn(&svc->dev, "no primary interface detected on module %u\n",
 966			 module_id);
 967	}
 968
 969	module = gb_svc_module_lookup(svc, module_id);
 970	if (module) {
 971		dev_warn(&svc->dev, "unexpected module-inserted event %u\n",
 972			 module_id);
 973		return;
 974	}
 975
 976	module = gb_module_create(hd, module_id, num_interfaces);
 977	if (!module) {
 978		dev_err(&svc->dev, "failed to create module\n");
 979		return;
 980	}
 981
 982	ret = gb_module_add(module);
 983	if (ret) {
 984		gb_module_put(module);
 985		return;
 986	}
 987
 988	list_add(&module->hd_node, &hd->modules);
 989}
 990
 991static void gb_svc_process_module_removed(struct gb_operation *operation)
 992{
 993	struct gb_svc_module_removed_request *request;
 994	struct gb_connection *connection = operation->connection;
 995	struct gb_svc *svc = gb_connection_get_data(connection);
 996	struct gb_module *module;
 997	u8 module_id;
 998
 999	/* The request message size has already been verified. */
1000	request = operation->request->payload;
1001	module_id = request->primary_intf_id;
1002
1003	dev_dbg(&svc->dev, "%s - id = %u\n", __func__, module_id);
1004
1005	module = gb_svc_module_lookup(svc, module_id);
1006	if (!module) {
1007		dev_warn(&svc->dev, "unexpected module-removed event %u\n",
1008			 module_id);
1009		return;
1010	}
1011
1012	module->disconnected = true;
1013
1014	gb_module_del(module);
1015	list_del(&module->hd_node);
1016	gb_module_put(module);
1017}
1018
1019static void gb_svc_process_intf_oops(struct gb_operation *operation)
1020{
1021	struct gb_svc_intf_oops_request *request;
1022	struct gb_connection *connection = operation->connection;
1023	struct gb_svc *svc = gb_connection_get_data(connection);
1024	struct gb_interface *intf;
1025	u8 intf_id;
1026	u8 reason;
1027
1028	/* The request message size has already been verified. */
1029	request = operation->request->payload;
1030	intf_id = request->intf_id;
1031	reason = request->reason;
1032
1033	intf = gb_svc_interface_lookup(svc, intf_id);
1034	if (!intf) {
1035		dev_warn(&svc->dev, "unexpected interface-oops event %u\n",
1036			 intf_id);
1037		return;
1038	}
1039
1040	dev_info(&svc->dev, "Deactivating interface %u, interface oops reason = %u\n",
1041		 intf_id, reason);
1042
1043	mutex_lock(&intf->mutex);
1044	intf->disconnected = true;
1045	gb_interface_disable(intf);
1046	gb_interface_deactivate(intf);
1047	mutex_unlock(&intf->mutex);
1048}
1049
1050static void gb_svc_process_intf_mailbox_event(struct gb_operation *operation)
1051{
1052	struct gb_svc_intf_mailbox_event_request *request;
1053	struct gb_connection *connection = operation->connection;
1054	struct gb_svc *svc = gb_connection_get_data(connection);
1055	struct gb_interface *intf;
1056	u8 intf_id;
1057	u16 result_code;
1058	u32 mailbox;
1059
1060	/* The request message size has already been verified. */
1061	request = operation->request->payload;
1062	intf_id = request->intf_id;
1063	result_code = le16_to_cpu(request->result_code);
1064	mailbox = le32_to_cpu(request->mailbox);
1065
1066	dev_dbg(&svc->dev, "%s - id = %u, result = 0x%04x, mailbox = 0x%08x\n",
1067		__func__, intf_id, result_code, mailbox);
1068
1069	intf = gb_svc_interface_lookup(svc, intf_id);
1070	if (!intf) {
1071		dev_warn(&svc->dev, "unexpected mailbox event %u\n", intf_id);
1072		return;
1073	}
1074
1075	gb_interface_mailbox_event(intf, result_code, mailbox);
1076}
1077
1078static void gb_svc_process_deferred_request(struct work_struct *work)
1079{
1080	struct gb_svc_deferred_request *dr;
1081	struct gb_operation *operation;
1082	struct gb_svc *svc;
1083	u8 type;
1084
1085	dr = container_of(work, struct gb_svc_deferred_request, work);
1086	operation = dr->operation;
1087	svc = gb_connection_get_data(operation->connection);
1088	type = operation->request->header->type;
1089
1090	switch (type) {
1091	case GB_SVC_TYPE_SVC_HELLO:
1092		gb_svc_process_hello_deferred(operation);
1093		break;
1094	case GB_SVC_TYPE_MODULE_INSERTED:
1095		gb_svc_process_module_inserted(operation);
1096		break;
1097	case GB_SVC_TYPE_MODULE_REMOVED:
1098		gb_svc_process_module_removed(operation);
1099		break;
1100	case GB_SVC_TYPE_INTF_MAILBOX_EVENT:
1101		gb_svc_process_intf_mailbox_event(operation);
1102		break;
1103	case GB_SVC_TYPE_INTF_OOPS:
1104		gb_svc_process_intf_oops(operation);
1105		break;
1106	default:
1107		dev_err(&svc->dev, "bad deferred request type: 0x%02x\n", type);
1108	}
1109
1110	gb_operation_put(operation);
1111	kfree(dr);
1112}
1113
1114static int gb_svc_queue_deferred_request(struct gb_operation *operation)
1115{
1116	struct gb_svc *svc = gb_connection_get_data(operation->connection);
1117	struct gb_svc_deferred_request *dr;
1118
1119	dr = kmalloc(sizeof(*dr), GFP_KERNEL);
1120	if (!dr)
1121		return -ENOMEM;
1122
1123	gb_operation_get(operation);
1124
1125	dr->operation = operation;
1126	INIT_WORK(&dr->work, gb_svc_process_deferred_request);
1127
1128	queue_work(svc->wq, &dr->work);
1129
1130	return 0;
1131}
1132
1133static int gb_svc_intf_reset_recv(struct gb_operation *op)
1134{
1135	struct gb_svc *svc = gb_connection_get_data(op->connection);
1136	struct gb_message *request = op->request;
1137	struct gb_svc_intf_reset_request *reset;
1138
1139	if (request->payload_size < sizeof(*reset)) {
1140		dev_warn(&svc->dev, "short reset request received (%zu < %zu)\n",
1141			 request->payload_size, sizeof(*reset));
1142		return -EINVAL;
1143	}
1144	reset = request->payload;
1145
1146	/* FIXME Reset the interface here */
1147
1148	return 0;
1149}
1150
1151static int gb_svc_module_inserted_recv(struct gb_operation *op)
1152{
1153	struct gb_svc *svc = gb_connection_get_data(op->connection);
1154	struct gb_svc_module_inserted_request *request;
1155
1156	if (op->request->payload_size < sizeof(*request)) {
1157		dev_warn(&svc->dev, "short module-inserted request received (%zu < %zu)\n",
1158			 op->request->payload_size, sizeof(*request));
1159		return -EINVAL;
1160	}
1161
1162	request = op->request->payload;
1163
1164	dev_dbg(&svc->dev, "%s - id = %u\n", __func__,
1165		request->primary_intf_id);
1166
1167	return gb_svc_queue_deferred_request(op);
1168}
1169
1170static int gb_svc_module_removed_recv(struct gb_operation *op)
1171{
1172	struct gb_svc *svc = gb_connection_get_data(op->connection);
1173	struct gb_svc_module_removed_request *request;
1174
1175	if (op->request->payload_size < sizeof(*request)) {
1176		dev_warn(&svc->dev, "short module-removed request received (%zu < %zu)\n",
1177			 op->request->payload_size, sizeof(*request));
1178		return -EINVAL;
1179	}
1180
1181	request = op->request->payload;
1182
1183	dev_dbg(&svc->dev, "%s - id = %u\n", __func__,
1184		request->primary_intf_id);
1185
1186	return gb_svc_queue_deferred_request(op);
1187}
1188
1189static int gb_svc_intf_oops_recv(struct gb_operation *op)
1190{
1191	struct gb_svc *svc = gb_connection_get_data(op->connection);
1192	struct gb_svc_intf_oops_request *request;
1193
1194	if (op->request->payload_size < sizeof(*request)) {
1195		dev_warn(&svc->dev, "short intf-oops request received (%zu < %zu)\n",
1196			 op->request->payload_size, sizeof(*request));
1197		return -EINVAL;
1198	}
1199
1200	return gb_svc_queue_deferred_request(op);
1201}
1202
1203static int gb_svc_intf_mailbox_event_recv(struct gb_operation *op)
1204{
1205	struct gb_svc *svc = gb_connection_get_data(op->connection);
1206	struct gb_svc_intf_mailbox_event_request *request;
1207
1208	if (op->request->payload_size < sizeof(*request)) {
1209		dev_warn(&svc->dev, "short mailbox request received (%zu < %zu)\n",
1210			 op->request->payload_size, sizeof(*request));
1211		return -EINVAL;
1212	}
1213
1214	request = op->request->payload;
1215
1216	dev_dbg(&svc->dev, "%s - id = %u\n", __func__, request->intf_id);
1217
1218	return gb_svc_queue_deferred_request(op);
1219}
1220
1221static int gb_svc_request_handler(struct gb_operation *op)
1222{
1223	struct gb_connection *connection = op->connection;
1224	struct gb_svc *svc = gb_connection_get_data(connection);
1225	u8 type = op->type;
1226	int ret = 0;
1227
1228	/*
1229	 * SVC requests need to follow a specific order (at least initially) and
1230	 * below code takes care of enforcing that. The expected order is:
1231	 * - PROTOCOL_VERSION
1232	 * - SVC_HELLO
1233	 * - Any other request, but the earlier two.
1234	 *
1235	 * Incoming requests are guaranteed to be serialized and so we don't
1236	 * need to protect 'state' for any races.
1237	 */
1238	switch (type) {
1239	case GB_SVC_TYPE_PROTOCOL_VERSION:
1240		if (svc->state != GB_SVC_STATE_RESET)
1241			ret = -EINVAL;
1242		break;
1243	case GB_SVC_TYPE_SVC_HELLO:
1244		if (svc->state != GB_SVC_STATE_PROTOCOL_VERSION)
1245			ret = -EINVAL;
1246		break;
1247	default:
1248		if (svc->state != GB_SVC_STATE_SVC_HELLO)
1249			ret = -EINVAL;
1250		break;
1251	}
1252
1253	if (ret) {
1254		dev_warn(&svc->dev, "unexpected request 0x%02x received (state %u)\n",
1255			 type, svc->state);
1256		return ret;
1257	}
1258
1259	switch (type) {
1260	case GB_SVC_TYPE_PROTOCOL_VERSION:
1261		ret = gb_svc_version_request(op);
1262		if (!ret)
1263			svc->state = GB_SVC_STATE_PROTOCOL_VERSION;
1264		return ret;
1265	case GB_SVC_TYPE_SVC_HELLO:
1266		ret = gb_svc_hello(op);
1267		if (!ret)
1268			svc->state = GB_SVC_STATE_SVC_HELLO;
1269		return ret;
1270	case GB_SVC_TYPE_INTF_RESET:
1271		return gb_svc_intf_reset_recv(op);
1272	case GB_SVC_TYPE_MODULE_INSERTED:
1273		return gb_svc_module_inserted_recv(op);
1274	case GB_SVC_TYPE_MODULE_REMOVED:
1275		return gb_svc_module_removed_recv(op);
1276	case GB_SVC_TYPE_INTF_MAILBOX_EVENT:
1277		return gb_svc_intf_mailbox_event_recv(op);
1278	case GB_SVC_TYPE_INTF_OOPS:
1279		return gb_svc_intf_oops_recv(op);
1280	default:
1281		dev_warn(&svc->dev, "unsupported request 0x%02x\n", type);
1282		return -EINVAL;
1283	}
1284}
1285
1286static void gb_svc_release(struct device *dev)
1287{
1288	struct gb_svc *svc = to_gb_svc(dev);
1289
1290	if (svc->connection)
1291		gb_connection_destroy(svc->connection);
1292	ida_destroy(&svc->device_id_map);
1293	destroy_workqueue(svc->wq);
1294	kfree(svc);
1295}
1296
1297struct device_type greybus_svc_type = {
1298	.name		= "greybus_svc",
1299	.release	= gb_svc_release,
1300};
1301
1302struct gb_svc *gb_svc_create(struct gb_host_device *hd)
1303{
1304	struct gb_svc *svc;
1305
1306	svc = kzalloc(sizeof(*svc), GFP_KERNEL);
1307	if (!svc)
1308		return NULL;
1309
1310	svc->wq = alloc_workqueue("%s:svc", WQ_UNBOUND, 1, dev_name(&hd->dev));
1311	if (!svc->wq) {
1312		kfree(svc);
1313		return NULL;
1314	}
1315
1316	svc->dev.parent = &hd->dev;
1317	svc->dev.bus = &greybus_bus_type;
1318	svc->dev.type = &greybus_svc_type;
1319	svc->dev.groups = svc_groups;
1320	svc->dev.dma_mask = svc->dev.parent->dma_mask;
1321	device_initialize(&svc->dev);
1322
1323	dev_set_name(&svc->dev, "%d-svc", hd->bus_id);
1324
1325	ida_init(&svc->device_id_map);
1326	svc->state = GB_SVC_STATE_RESET;
1327	svc->hd = hd;
1328
1329	svc->connection = gb_connection_create_static(hd, GB_SVC_CPORT_ID,
1330						      gb_svc_request_handler);
1331	if (IS_ERR(svc->connection)) {
1332		dev_err(&svc->dev, "failed to create connection: %ld\n",
1333			PTR_ERR(svc->connection));
1334		goto err_put_device;
1335	}
1336
1337	gb_connection_set_data(svc->connection, svc);
1338
1339	return svc;
1340
1341err_put_device:
1342	put_device(&svc->dev);
1343	return NULL;
1344}
1345
1346int gb_svc_add(struct gb_svc *svc)
1347{
1348	int ret;
1349
1350	/*
1351	 * The SVC protocol is currently driven by the SVC, so the SVC device
1352	 * is added from the connection request handler when enough
1353	 * information has been received.
1354	 */
1355	ret = gb_connection_enable(svc->connection);
1356	if (ret)
1357		return ret;
1358
1359	return 0;
1360}
1361
1362static void gb_svc_remove_modules(struct gb_svc *svc)
1363{
1364	struct gb_host_device *hd = svc->hd;
1365	struct gb_module *module, *tmp;
1366
1367	list_for_each_entry_safe(module, tmp, &hd->modules, hd_node) {
1368		gb_module_del(module);
1369		list_del(&module->hd_node);
1370		gb_module_put(module);
1371	}
1372}
1373
1374void gb_svc_del(struct gb_svc *svc)
1375{
1376	gb_connection_disable_rx(svc->connection);
1377
1378	/*
1379	 * The SVC device may have been registered from the request handler.
1380	 */
1381	if (device_is_registered(&svc->dev)) {
1382		gb_svc_debugfs_exit(svc);
1383		gb_svc_watchdog_destroy(svc);
1384		device_del(&svc->dev);
1385	}
1386
1387	flush_workqueue(svc->wq);
1388
1389	gb_svc_remove_modules(svc);
1390
1391	gb_connection_disable(svc->connection);
1392}
1393
1394void gb_svc_put(struct gb_svc *svc)
1395{
1396	put_device(&svc->dev);
1397}