xref: /linux/drivers/greybus/svc.c (revision c21614d5c0e76cf1d7a864f15d495fd3e5876acc)
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/kstrtox.h>
11 #include <linux/workqueue.h>
12 #include <linux/greybus.h>
13 
14 #define SVC_INTF_EJECT_TIMEOUT		9000
15 #define SVC_INTF_ACTIVATE_TIMEOUT	6000
16 #define SVC_INTF_RESUME_TIMEOUT		3000
17 
18 struct gb_svc_deferred_request {
19 	struct work_struct work;
20 	struct gb_operation *operation;
21 };
22 
23 static int gb_svc_queue_deferred_request(struct gb_operation *operation);
24 
25 static ssize_t endo_id_show(struct device *dev,
26 			    struct device_attribute *attr, char *buf)
27 {
28 	struct gb_svc *svc = to_gb_svc(dev);
29 
30 	return sprintf(buf, "0x%04x\n", svc->endo_id);
31 }
32 static DEVICE_ATTR_RO(endo_id);
33 
34 static ssize_t ap_intf_id_show(struct device *dev,
35 			       struct device_attribute *attr, char *buf)
36 {
37 	struct gb_svc *svc = to_gb_svc(dev);
38 
39 	return sprintf(buf, "%u\n", svc->ap_intf_id);
40 }
41 static DEVICE_ATTR_RO(ap_intf_id);
42 
43 // FIXME
44 // This is a hack, we need to do this "right" and clean the interface up
45 // properly, not just forcibly yank the thing out of the system and hope for the
46 // best.  But for now, people want their modules to come out without having to
47 // throw the thing to the ground or get out a screwdriver.
48 static ssize_t intf_eject_store(struct device *dev,
49 				struct device_attribute *attr, const char *buf,
50 				size_t len)
51 {
52 	struct gb_svc *svc = to_gb_svc(dev);
53 	unsigned short intf_id;
54 	int ret;
55 
56 	ret = kstrtou16(buf, 10, &intf_id);
57 	if (ret < 0)
58 		return ret;
59 
60 	dev_warn(dev, "Forcibly trying to eject interface %d\n", intf_id);
61 
62 	ret = gb_svc_intf_eject(svc, intf_id);
63 	if (ret < 0)
64 		return ret;
65 
66 	return len;
67 }
68 static DEVICE_ATTR_WO(intf_eject);
69 
70 static ssize_t watchdog_show(struct device *dev, struct device_attribute *attr,
71 			     char *buf)
72 {
73 	struct gb_svc *svc = to_gb_svc(dev);
74 
75 	return sprintf(buf, "%s\n",
76 		       gb_svc_watchdog_enabled(svc) ? "enabled" : "disabled");
77 }
78 
79 static ssize_t watchdog_store(struct device *dev,
80 			      struct device_attribute *attr, const char *buf,
81 			      size_t len)
82 {
83 	struct gb_svc *svc = to_gb_svc(dev);
84 	int retval;
85 	bool user_request;
86 
87 	retval = kstrtobool(buf, &user_request);
88 	if (retval)
89 		return retval;
90 
91 	if (user_request)
92 		retval = gb_svc_watchdog_enable(svc);
93 	else
94 		retval = gb_svc_watchdog_disable(svc);
95 	if (retval)
96 		return retval;
97 	return len;
98 }
99 static DEVICE_ATTR_RW(watchdog);
100 
101 static ssize_t watchdog_action_show(struct device *dev,
102 				    struct device_attribute *attr, char *buf)
103 {
104 	struct gb_svc *svc = to_gb_svc(dev);
105 
106 	if (svc->action == GB_SVC_WATCHDOG_BITE_PANIC_KERNEL)
107 		return sprintf(buf, "panic\n");
108 	else if (svc->action == GB_SVC_WATCHDOG_BITE_RESET_UNIPRO)
109 		return sprintf(buf, "reset\n");
110 
111 	return -EINVAL;
112 }
113 
114 static ssize_t watchdog_action_store(struct device *dev,
115 				     struct device_attribute *attr,
116 				     const char *buf, size_t len)
117 {
118 	struct gb_svc *svc = to_gb_svc(dev);
119 
120 	if (sysfs_streq(buf, "panic"))
121 		svc->action = GB_SVC_WATCHDOG_BITE_PANIC_KERNEL;
122 	else if (sysfs_streq(buf, "reset"))
123 		svc->action = GB_SVC_WATCHDOG_BITE_RESET_UNIPRO;
124 	else
125 		return -EINVAL;
126 
127 	return len;
128 }
129 static DEVICE_ATTR_RW(watchdog_action);
130 
131 static int gb_svc_pwrmon_rail_count_get(struct gb_svc *svc, u8 *value)
132 {
133 	struct gb_svc_pwrmon_rail_count_get_response response;
134 	int ret;
135 
136 	ret = gb_operation_sync(svc->connection,
137 				GB_SVC_TYPE_PWRMON_RAIL_COUNT_GET, NULL, 0,
138 				&response, sizeof(response));
139 	if (ret) {
140 		dev_err(&svc->dev, "failed to get rail count: %d\n", ret);
141 		return ret;
142 	}
143 
144 	*value = response.rail_count;
145 
146 	return 0;
147 }
148 
149 static int gb_svc_pwrmon_rail_names_get(struct gb_svc *svc,
150 		struct gb_svc_pwrmon_rail_names_get_response *response,
151 		size_t bufsize)
152 {
153 	int ret;
154 
155 	ret = gb_operation_sync(svc->connection,
156 				GB_SVC_TYPE_PWRMON_RAIL_NAMES_GET, NULL, 0,
157 				response, bufsize);
158 	if (ret) {
159 		dev_err(&svc->dev, "failed to get rail names: %d\n", ret);
160 		return ret;
161 	}
162 
163 	if (response->status != GB_SVC_OP_SUCCESS) {
164 		dev_err(&svc->dev,
165 			"SVC error while getting rail names: %u\n",
166 			response->status);
167 		return -EREMOTEIO;
168 	}
169 
170 	return 0;
171 }
172 
173 static int gb_svc_pwrmon_sample_get(struct gb_svc *svc, u8 rail_id,
174 				    u8 measurement_type, u32 *value)
175 {
176 	struct gb_svc_pwrmon_sample_get_request request;
177 	struct gb_svc_pwrmon_sample_get_response response;
178 	int ret;
179 
180 	request.rail_id = rail_id;
181 	request.measurement_type = measurement_type;
182 
183 	ret = gb_operation_sync(svc->connection, GB_SVC_TYPE_PWRMON_SAMPLE_GET,
184 				&request, sizeof(request),
185 				&response, sizeof(response));
186 	if (ret) {
187 		dev_err(&svc->dev, "failed to get rail sample: %d\n", ret);
188 		return ret;
189 	}
190 
191 	if (response.result) {
192 		dev_err(&svc->dev,
193 			"UniPro error while getting rail power sample (%d %d): %d\n",
194 			rail_id, measurement_type, response.result);
195 		switch (response.result) {
196 		case GB_SVC_PWRMON_GET_SAMPLE_INVAL:
197 			return -EINVAL;
198 		case GB_SVC_PWRMON_GET_SAMPLE_NOSUPP:
199 			return -ENOMSG;
200 		default:
201 			return -EREMOTEIO;
202 		}
203 	}
204 
205 	*value = le32_to_cpu(response.measurement);
206 
207 	return 0;
208 }
209 
210 int gb_svc_pwrmon_intf_sample_get(struct gb_svc *svc, u8 intf_id,
211 				  u8 measurement_type, u32 *value)
212 {
213 	struct gb_svc_pwrmon_intf_sample_get_request request;
214 	struct gb_svc_pwrmon_intf_sample_get_response response;
215 	int ret;
216 
217 	request.intf_id = intf_id;
218 	request.measurement_type = measurement_type;
219 
220 	ret = gb_operation_sync(svc->connection,
221 				GB_SVC_TYPE_PWRMON_INTF_SAMPLE_GET,
222 				&request, sizeof(request),
223 				&response, sizeof(response));
224 	if (ret) {
225 		dev_err(&svc->dev, "failed to get intf sample: %d\n", ret);
226 		return ret;
227 	}
228 
229 	if (response.result) {
230 		dev_err(&svc->dev,
231 			"UniPro error while getting intf power sample (%d %d): %d\n",
232 			intf_id, measurement_type, response.result);
233 		switch (response.result) {
234 		case GB_SVC_PWRMON_GET_SAMPLE_INVAL:
235 			return -EINVAL;
236 		case GB_SVC_PWRMON_GET_SAMPLE_NOSUPP:
237 			return -ENOMSG;
238 		default:
239 			return -EREMOTEIO;
240 		}
241 	}
242 
243 	*value = le32_to_cpu(response.measurement);
244 
245 	return 0;
246 }
247 
248 static struct attribute *svc_attrs[] = {
249 	&dev_attr_endo_id.attr,
250 	&dev_attr_ap_intf_id.attr,
251 	&dev_attr_intf_eject.attr,
252 	&dev_attr_watchdog.attr,
253 	&dev_attr_watchdog_action.attr,
254 	NULL,
255 };
256 ATTRIBUTE_GROUPS(svc);
257 
258 int gb_svc_intf_device_id(struct gb_svc *svc, u8 intf_id, u8 device_id)
259 {
260 	struct gb_svc_intf_device_id_request request;
261 
262 	request.intf_id = intf_id;
263 	request.device_id = device_id;
264 
265 	return gb_operation_sync(svc->connection, GB_SVC_TYPE_INTF_DEVICE_ID,
266 				 &request, sizeof(request), NULL, 0);
267 }
268 
269 int gb_svc_intf_eject(struct gb_svc *svc, u8 intf_id)
270 {
271 	struct gb_svc_intf_eject_request request;
272 	int ret;
273 
274 	request.intf_id = intf_id;
275 
276 	/*
277 	 * The pulse width for module release in svc is long so we need to
278 	 * increase the timeout so the operation will not return to soon.
279 	 */
280 	ret = gb_operation_sync_timeout(svc->connection,
281 					GB_SVC_TYPE_INTF_EJECT, &request,
282 					sizeof(request), NULL, 0,
283 					SVC_INTF_EJECT_TIMEOUT);
284 	if (ret) {
285 		dev_err(&svc->dev, "failed to eject interface %u\n", intf_id);
286 		return ret;
287 	}
288 
289 	return 0;
290 }
291 
292 int gb_svc_intf_vsys_set(struct gb_svc *svc, u8 intf_id, bool enable)
293 {
294 	struct gb_svc_intf_vsys_request request;
295 	struct gb_svc_intf_vsys_response response;
296 	int type, ret;
297 
298 	request.intf_id = intf_id;
299 
300 	if (enable)
301 		type = GB_SVC_TYPE_INTF_VSYS_ENABLE;
302 	else
303 		type = GB_SVC_TYPE_INTF_VSYS_DISABLE;
304 
305 	ret = gb_operation_sync(svc->connection, type,
306 				&request, sizeof(request),
307 				&response, sizeof(response));
308 	if (ret < 0)
309 		return ret;
310 	if (response.result_code != GB_SVC_INTF_VSYS_OK)
311 		return -EREMOTEIO;
312 	return 0;
313 }
314 
315 int gb_svc_intf_refclk_set(struct gb_svc *svc, u8 intf_id, bool enable)
316 {
317 	struct gb_svc_intf_refclk_request request;
318 	struct gb_svc_intf_refclk_response response;
319 	int type, ret;
320 
321 	request.intf_id = intf_id;
322 
323 	if (enable)
324 		type = GB_SVC_TYPE_INTF_REFCLK_ENABLE;
325 	else
326 		type = GB_SVC_TYPE_INTF_REFCLK_DISABLE;
327 
328 	ret = gb_operation_sync(svc->connection, type,
329 				&request, sizeof(request),
330 				&response, sizeof(response));
331 	if (ret < 0)
332 		return ret;
333 	if (response.result_code != GB_SVC_INTF_REFCLK_OK)
334 		return -EREMOTEIO;
335 	return 0;
336 }
337 
338 int gb_svc_intf_unipro_set(struct gb_svc *svc, u8 intf_id, bool enable)
339 {
340 	struct gb_svc_intf_unipro_request request;
341 	struct gb_svc_intf_unipro_response response;
342 	int type, ret;
343 
344 	request.intf_id = intf_id;
345 
346 	if (enable)
347 		type = GB_SVC_TYPE_INTF_UNIPRO_ENABLE;
348 	else
349 		type = GB_SVC_TYPE_INTF_UNIPRO_DISABLE;
350 
351 	ret = gb_operation_sync(svc->connection, type,
352 				&request, sizeof(request),
353 				&response, sizeof(response));
354 	if (ret < 0)
355 		return ret;
356 	if (response.result_code != GB_SVC_INTF_UNIPRO_OK)
357 		return -EREMOTEIO;
358 	return 0;
359 }
360 
361 int gb_svc_intf_activate(struct gb_svc *svc, u8 intf_id, u8 *intf_type)
362 {
363 	struct gb_svc_intf_activate_request request;
364 	struct gb_svc_intf_activate_response response;
365 	int ret;
366 
367 	request.intf_id = intf_id;
368 
369 	ret = gb_operation_sync_timeout(svc->connection,
370 					GB_SVC_TYPE_INTF_ACTIVATE,
371 					&request, sizeof(request),
372 					&response, sizeof(response),
373 					SVC_INTF_ACTIVATE_TIMEOUT);
374 	if (ret < 0)
375 		return ret;
376 	if (response.status != GB_SVC_OP_SUCCESS) {
377 		dev_err(&svc->dev, "failed to activate interface %u: %u\n",
378 			intf_id, response.status);
379 		return -EREMOTEIO;
380 	}
381 
382 	*intf_type = response.intf_type;
383 
384 	return 0;
385 }
386 
387 int gb_svc_intf_resume(struct gb_svc *svc, u8 intf_id)
388 {
389 	struct gb_svc_intf_resume_request request;
390 	struct gb_svc_intf_resume_response response;
391 	int ret;
392 
393 	request.intf_id = intf_id;
394 
395 	ret = gb_operation_sync_timeout(svc->connection,
396 					GB_SVC_TYPE_INTF_RESUME,
397 					&request, sizeof(request),
398 					&response, sizeof(response),
399 					SVC_INTF_RESUME_TIMEOUT);
400 	if (ret < 0) {
401 		dev_err(&svc->dev, "failed to send interface resume %u: %d\n",
402 			intf_id, ret);
403 		return ret;
404 	}
405 
406 	if (response.status != GB_SVC_OP_SUCCESS) {
407 		dev_err(&svc->dev, "failed to resume interface %u: %u\n",
408 			intf_id, response.status);
409 		return -EREMOTEIO;
410 	}
411 
412 	return 0;
413 }
414 
415 int gb_svc_dme_peer_get(struct gb_svc *svc, u8 intf_id, u16 attr, u16 selector,
416 			u32 *value)
417 {
418 	struct gb_svc_dme_peer_get_request request;
419 	struct gb_svc_dme_peer_get_response response;
420 	u16 result;
421 	int ret;
422 
423 	request.intf_id = intf_id;
424 	request.attr = cpu_to_le16(attr);
425 	request.selector = cpu_to_le16(selector);
426 
427 	ret = gb_operation_sync(svc->connection, GB_SVC_TYPE_DME_PEER_GET,
428 				&request, sizeof(request),
429 				&response, sizeof(response));
430 	if (ret) {
431 		dev_err(&svc->dev, "failed to get DME attribute (%u 0x%04x %u): %d\n",
432 			intf_id, attr, selector, ret);
433 		return ret;
434 	}
435 
436 	result = le16_to_cpu(response.result_code);
437 	if (result) {
438 		dev_err(&svc->dev, "UniPro error while getting DME attribute (%u 0x%04x %u): %u\n",
439 			intf_id, attr, selector, result);
440 		return -EREMOTEIO;
441 	}
442 
443 	if (value)
444 		*value = le32_to_cpu(response.attr_value);
445 
446 	return 0;
447 }
448 
449 int gb_svc_dme_peer_set(struct gb_svc *svc, u8 intf_id, u16 attr, u16 selector,
450 			u32 value)
451 {
452 	struct gb_svc_dme_peer_set_request request;
453 	struct gb_svc_dme_peer_set_response response;
454 	u16 result;
455 	int ret;
456 
457 	request.intf_id = intf_id;
458 	request.attr = cpu_to_le16(attr);
459 	request.selector = cpu_to_le16(selector);
460 	request.value = cpu_to_le32(value);
461 
462 	ret = gb_operation_sync(svc->connection, GB_SVC_TYPE_DME_PEER_SET,
463 				&request, sizeof(request),
464 				&response, sizeof(response));
465 	if (ret) {
466 		dev_err(&svc->dev, "failed to set DME attribute (%u 0x%04x %u %u): %d\n",
467 			intf_id, attr, selector, value, ret);
468 		return ret;
469 	}
470 
471 	result = le16_to_cpu(response.result_code);
472 	if (result) {
473 		dev_err(&svc->dev, "UniPro error while setting DME attribute (%u 0x%04x %u %u): %u\n",
474 			intf_id, attr, selector, value, result);
475 		return -EREMOTEIO;
476 	}
477 
478 	return 0;
479 }
480 
481 int gb_svc_connection_create(struct gb_svc *svc,
482 			     u8 intf1_id, u16 cport1_id,
483 			     u8 intf2_id, u16 cport2_id,
484 			     u8 cport_flags)
485 {
486 	struct gb_svc_conn_create_request request;
487 
488 	request.intf1_id = intf1_id;
489 	request.cport1_id = cpu_to_le16(cport1_id);
490 	request.intf2_id = intf2_id;
491 	request.cport2_id = cpu_to_le16(cport2_id);
492 	request.tc = 0;		/* TC0 */
493 	request.flags = cport_flags;
494 
495 	return gb_operation_sync(svc->connection, GB_SVC_TYPE_CONN_CREATE,
496 				 &request, sizeof(request), NULL, 0);
497 }
498 
499 void gb_svc_connection_destroy(struct gb_svc *svc, u8 intf1_id, u16 cport1_id,
500 			       u8 intf2_id, u16 cport2_id)
501 {
502 	struct gb_svc_conn_destroy_request request;
503 	struct gb_connection *connection = svc->connection;
504 	int ret;
505 
506 	request.intf1_id = intf1_id;
507 	request.cport1_id = cpu_to_le16(cport1_id);
508 	request.intf2_id = intf2_id;
509 	request.cport2_id = cpu_to_le16(cport2_id);
510 
511 	ret = gb_operation_sync(connection, GB_SVC_TYPE_CONN_DESTROY,
512 				&request, sizeof(request), NULL, 0);
513 	if (ret) {
514 		dev_err(&svc->dev, "failed to destroy connection (%u:%u %u:%u): %d\n",
515 			intf1_id, cport1_id, intf2_id, cport2_id, ret);
516 	}
517 }
518 
519 /* Creates bi-directional routes between the devices */
520 int gb_svc_route_create(struct gb_svc *svc, u8 intf1_id, u8 dev1_id,
521 			u8 intf2_id, u8 dev2_id)
522 {
523 	struct gb_svc_route_create_request request;
524 
525 	request.intf1_id = intf1_id;
526 	request.dev1_id = dev1_id;
527 	request.intf2_id = intf2_id;
528 	request.dev2_id = dev2_id;
529 
530 	return gb_operation_sync(svc->connection, GB_SVC_TYPE_ROUTE_CREATE,
531 				 &request, sizeof(request), NULL, 0);
532 }
533 
534 /* Destroys bi-directional routes between the devices */
535 void gb_svc_route_destroy(struct gb_svc *svc, u8 intf1_id, u8 intf2_id)
536 {
537 	struct gb_svc_route_destroy_request request;
538 	int ret;
539 
540 	request.intf1_id = intf1_id;
541 	request.intf2_id = intf2_id;
542 
543 	ret = gb_operation_sync(svc->connection, GB_SVC_TYPE_ROUTE_DESTROY,
544 				&request, sizeof(request), NULL, 0);
545 	if (ret) {
546 		dev_err(&svc->dev, "failed to destroy route (%u %u): %d\n",
547 			intf1_id, intf2_id, ret);
548 	}
549 }
550 
551 int gb_svc_intf_set_power_mode(struct gb_svc *svc, u8 intf_id, u8 hs_series,
552 			       u8 tx_mode, u8 tx_gear, u8 tx_nlanes,
553 			       u8 tx_amplitude, u8 tx_hs_equalizer,
554 			       u8 rx_mode, u8 rx_gear, u8 rx_nlanes,
555 			       u8 flags, u32 quirks,
556 			       struct gb_svc_l2_timer_cfg *local,
557 			       struct gb_svc_l2_timer_cfg *remote)
558 {
559 	struct gb_svc_intf_set_pwrm_request request;
560 	struct gb_svc_intf_set_pwrm_response response;
561 	int ret;
562 	u16 result_code;
563 
564 	memset(&request, 0, sizeof(request));
565 
566 	request.intf_id = intf_id;
567 	request.hs_series = hs_series;
568 	request.tx_mode = tx_mode;
569 	request.tx_gear = tx_gear;
570 	request.tx_nlanes = tx_nlanes;
571 	request.tx_amplitude = tx_amplitude;
572 	request.tx_hs_equalizer = tx_hs_equalizer;
573 	request.rx_mode = rx_mode;
574 	request.rx_gear = rx_gear;
575 	request.rx_nlanes = rx_nlanes;
576 	request.flags = flags;
577 	request.quirks = cpu_to_le32(quirks);
578 	if (local)
579 		request.local_l2timerdata = *local;
580 	if (remote)
581 		request.remote_l2timerdata = *remote;
582 
583 	ret = gb_operation_sync(svc->connection, GB_SVC_TYPE_INTF_SET_PWRM,
584 				&request, sizeof(request),
585 				&response, sizeof(response));
586 	if (ret < 0)
587 		return ret;
588 
589 	result_code = response.result_code;
590 	if (result_code != GB_SVC_SETPWRM_PWR_LOCAL) {
591 		dev_err(&svc->dev, "set power mode = %d\n", result_code);
592 		return -EIO;
593 	}
594 
595 	return 0;
596 }
597 EXPORT_SYMBOL_GPL(gb_svc_intf_set_power_mode);
598 
599 int gb_svc_intf_set_power_mode_hibernate(struct gb_svc *svc, u8 intf_id)
600 {
601 	struct gb_svc_intf_set_pwrm_request request;
602 	struct gb_svc_intf_set_pwrm_response response;
603 	int ret;
604 	u16 result_code;
605 
606 	memset(&request, 0, sizeof(request));
607 
608 	request.intf_id = intf_id;
609 	request.hs_series = GB_SVC_UNIPRO_HS_SERIES_A;
610 	request.tx_mode = GB_SVC_UNIPRO_HIBERNATE_MODE;
611 	request.rx_mode = GB_SVC_UNIPRO_HIBERNATE_MODE;
612 
613 	ret = gb_operation_sync(svc->connection, GB_SVC_TYPE_INTF_SET_PWRM,
614 				&request, sizeof(request),
615 				&response, sizeof(response));
616 	if (ret < 0) {
617 		dev_err(&svc->dev,
618 			"failed to send set power mode operation to interface %u: %d\n",
619 			intf_id, ret);
620 		return ret;
621 	}
622 
623 	result_code = response.result_code;
624 	if (result_code != GB_SVC_SETPWRM_PWR_OK) {
625 		dev_err(&svc->dev,
626 			"failed to hibernate the link for interface %u: %u\n",
627 			intf_id, result_code);
628 		return -EIO;
629 	}
630 
631 	return 0;
632 }
633 
634 int gb_svc_ping(struct gb_svc *svc)
635 {
636 	return gb_operation_sync_timeout(svc->connection, GB_SVC_TYPE_PING,
637 					 NULL, 0, NULL, 0,
638 					 GB_OPERATION_TIMEOUT_DEFAULT * 2);
639 }
640 
641 static int gb_svc_version_request(struct gb_operation *op)
642 {
643 	struct gb_connection *connection = op->connection;
644 	struct gb_svc *svc = gb_connection_get_data(connection);
645 	struct gb_svc_version_request *request;
646 	struct gb_svc_version_response *response;
647 
648 	if (op->request->payload_size < sizeof(*request)) {
649 		dev_err(&svc->dev, "short version request (%zu < %zu)\n",
650 			op->request->payload_size,
651 			sizeof(*request));
652 		return -EINVAL;
653 	}
654 
655 	request = op->request->payload;
656 
657 	if (request->major > GB_SVC_VERSION_MAJOR) {
658 		dev_warn(&svc->dev, "unsupported major version (%u > %u)\n",
659 			 request->major, GB_SVC_VERSION_MAJOR);
660 		return -ENOTSUPP;
661 	}
662 
663 	svc->protocol_major = request->major;
664 	svc->protocol_minor = request->minor;
665 
666 	if (!gb_operation_response_alloc(op, sizeof(*response), GFP_KERNEL))
667 		return -ENOMEM;
668 
669 	response = op->response->payload;
670 	response->major = svc->protocol_major;
671 	response->minor = svc->protocol_minor;
672 
673 	return 0;
674 }
675 
676 static ssize_t pwr_debugfs_voltage_read(struct file *file, char __user *buf,
677 					size_t len, loff_t *offset)
678 {
679 	struct svc_debugfs_pwrmon_rail *pwrmon_rails =
680 		file_inode(file)->i_private;
681 	struct gb_svc *svc = pwrmon_rails->svc;
682 	int ret, desc;
683 	u32 value;
684 	char buff[16];
685 
686 	ret = gb_svc_pwrmon_sample_get(svc, pwrmon_rails->id,
687 				       GB_SVC_PWRMON_TYPE_VOL, &value);
688 	if (ret) {
689 		dev_err(&svc->dev,
690 			"failed to get voltage sample %u: %d\n",
691 			pwrmon_rails->id, ret);
692 		return ret;
693 	}
694 
695 	desc = scnprintf(buff, sizeof(buff), "%u\n", value);
696 
697 	return simple_read_from_buffer(buf, len, offset, buff, desc);
698 }
699 
700 static ssize_t pwr_debugfs_current_read(struct file *file, char __user *buf,
701 					size_t len, loff_t *offset)
702 {
703 	struct svc_debugfs_pwrmon_rail *pwrmon_rails =
704 		file_inode(file)->i_private;
705 	struct gb_svc *svc = pwrmon_rails->svc;
706 	int ret, desc;
707 	u32 value;
708 	char buff[16];
709 
710 	ret = gb_svc_pwrmon_sample_get(svc, pwrmon_rails->id,
711 				       GB_SVC_PWRMON_TYPE_CURR, &value);
712 	if (ret) {
713 		dev_err(&svc->dev,
714 			"failed to get current sample %u: %d\n",
715 			pwrmon_rails->id, ret);
716 		return ret;
717 	}
718 
719 	desc = scnprintf(buff, sizeof(buff), "%u\n", value);
720 
721 	return simple_read_from_buffer(buf, len, offset, buff, desc);
722 }
723 
724 static ssize_t pwr_debugfs_power_read(struct file *file, char __user *buf,
725 				      size_t len, loff_t *offset)
726 {
727 	struct svc_debugfs_pwrmon_rail *pwrmon_rails =
728 		file_inode(file)->i_private;
729 	struct gb_svc *svc = pwrmon_rails->svc;
730 	int ret, desc;
731 	u32 value;
732 	char buff[16];
733 
734 	ret = gb_svc_pwrmon_sample_get(svc, pwrmon_rails->id,
735 				       GB_SVC_PWRMON_TYPE_PWR, &value);
736 	if (ret) {
737 		dev_err(&svc->dev, "failed to get power sample %u: %d\n",
738 			pwrmon_rails->id, ret);
739 		return ret;
740 	}
741 
742 	desc = scnprintf(buff, sizeof(buff), "%u\n", value);
743 
744 	return simple_read_from_buffer(buf, len, offset, buff, desc);
745 }
746 
747 static const struct file_operations pwrmon_debugfs_voltage_fops = {
748 	.read		= pwr_debugfs_voltage_read,
749 };
750 
751 static const struct file_operations pwrmon_debugfs_current_fops = {
752 	.read		= pwr_debugfs_current_read,
753 };
754 
755 static const struct file_operations pwrmon_debugfs_power_fops = {
756 	.read		= pwr_debugfs_power_read,
757 };
758 
759 static void gb_svc_pwrmon_debugfs_init(struct gb_svc *svc)
760 {
761 	int i;
762 	size_t bufsize;
763 	struct dentry *dent;
764 	struct gb_svc_pwrmon_rail_names_get_response *rail_names;
765 	u8 rail_count;
766 
767 	dent = debugfs_create_dir("pwrmon", svc->debugfs_dentry);
768 	if (IS_ERR_OR_NULL(dent))
769 		return;
770 
771 	if (gb_svc_pwrmon_rail_count_get(svc, &rail_count))
772 		goto err_pwrmon_debugfs;
773 
774 	if (!rail_count || rail_count > GB_SVC_PWRMON_MAX_RAIL_COUNT)
775 		goto err_pwrmon_debugfs;
776 
777 	bufsize = sizeof(*rail_names) +
778 		GB_SVC_PWRMON_RAIL_NAME_BUFSIZE * rail_count;
779 
780 	rail_names = kzalloc(bufsize, GFP_KERNEL);
781 	if (!rail_names)
782 		goto err_pwrmon_debugfs;
783 
784 	svc->pwrmon_rails = kcalloc(rail_count, sizeof(*svc->pwrmon_rails),
785 				    GFP_KERNEL);
786 	if (!svc->pwrmon_rails)
787 		goto err_pwrmon_debugfs_free;
788 
789 	if (gb_svc_pwrmon_rail_names_get(svc, rail_names, bufsize))
790 		goto err_pwrmon_debugfs_free;
791 
792 	for (i = 0; i < rail_count; i++) {
793 		struct dentry *dir;
794 		struct svc_debugfs_pwrmon_rail *rail = &svc->pwrmon_rails[i];
795 		char fname[GB_SVC_PWRMON_RAIL_NAME_BUFSIZE];
796 
797 		snprintf(fname, sizeof(fname), "%s",
798 			 (char *)&rail_names->name[i]);
799 
800 		rail->id = i;
801 		rail->svc = svc;
802 
803 		dir = debugfs_create_dir(fname, dent);
804 		debugfs_create_file("voltage_now", 0444, dir, rail,
805 				    &pwrmon_debugfs_voltage_fops);
806 		debugfs_create_file("current_now", 0444, dir, rail,
807 				    &pwrmon_debugfs_current_fops);
808 		debugfs_create_file("power_now", 0444, dir, rail,
809 				    &pwrmon_debugfs_power_fops);
810 	}
811 
812 	kfree(rail_names);
813 	return;
814 
815 err_pwrmon_debugfs_free:
816 	kfree(rail_names);
817 	kfree(svc->pwrmon_rails);
818 	svc->pwrmon_rails = NULL;
819 
820 err_pwrmon_debugfs:
821 	debugfs_remove(dent);
822 }
823 
824 static void gb_svc_debugfs_init(struct gb_svc *svc)
825 {
826 	svc->debugfs_dentry = debugfs_create_dir(dev_name(&svc->dev),
827 						 gb_debugfs_get());
828 	gb_svc_pwrmon_debugfs_init(svc);
829 }
830 
831 static void gb_svc_debugfs_exit(struct gb_svc *svc)
832 {
833 	debugfs_remove_recursive(svc->debugfs_dentry);
834 	kfree(svc->pwrmon_rails);
835 	svc->pwrmon_rails = NULL;
836 }
837 
838 static int gb_svc_hello(struct gb_operation *op)
839 {
840 	struct gb_connection *connection = op->connection;
841 	struct gb_svc *svc = gb_connection_get_data(connection);
842 	struct gb_svc_hello_request *hello_request;
843 	int ret;
844 
845 	if (op->request->payload_size < sizeof(*hello_request)) {
846 		dev_warn(&svc->dev, "short hello request (%zu < %zu)\n",
847 			 op->request->payload_size,
848 			 sizeof(*hello_request));
849 		return -EINVAL;
850 	}
851 
852 	hello_request = op->request->payload;
853 	svc->endo_id = le16_to_cpu(hello_request->endo_id);
854 	svc->ap_intf_id = hello_request->interface_id;
855 
856 	ret = device_add(&svc->dev);
857 	if (ret) {
858 		dev_err(&svc->dev, "failed to register svc device: %d\n", ret);
859 		return ret;
860 	}
861 
862 	ret = gb_svc_watchdog_create(svc);
863 	if (ret) {
864 		dev_err(&svc->dev, "failed to create watchdog: %d\n", ret);
865 		goto err_deregister_svc;
866 	}
867 
868 	/*
869 	 * FIXME: This is a temporary hack to reconfigure the link at HELLO
870 	 * (which abuses the deferred request processing mechanism).
871 	 */
872 	ret = gb_svc_queue_deferred_request(op);
873 	if (ret)
874 		goto err_destroy_watchdog;
875 
876 	gb_svc_debugfs_init(svc);
877 
878 	return 0;
879 
880 err_destroy_watchdog:
881 	gb_svc_watchdog_destroy(svc);
882 err_deregister_svc:
883 	device_del(&svc->dev);
884 
885 	return ret;
886 }
887 
888 static struct gb_interface *gb_svc_interface_lookup(struct gb_svc *svc,
889 						    u8 intf_id)
890 {
891 	struct gb_host_device *hd = svc->hd;
892 	struct gb_module *module;
893 	size_t num_interfaces;
894 	u8 module_id;
895 
896 	list_for_each_entry(module, &hd->modules, hd_node) {
897 		module_id = module->module_id;
898 		num_interfaces = module->num_interfaces;
899 
900 		if (intf_id >= module_id &&
901 		    intf_id < module_id + num_interfaces) {
902 			return module->interfaces[intf_id - module_id];
903 		}
904 	}
905 
906 	return NULL;
907 }
908 
909 static struct gb_module *gb_svc_module_lookup(struct gb_svc *svc, u8 module_id)
910 {
911 	struct gb_host_device *hd = svc->hd;
912 	struct gb_module *module;
913 
914 	list_for_each_entry(module, &hd->modules, hd_node) {
915 		if (module->module_id == module_id)
916 			return module;
917 	}
918 
919 	return NULL;
920 }
921 
922 static void gb_svc_process_hello_deferred(struct gb_operation *operation)
923 {
924 	struct gb_connection *connection = operation->connection;
925 	struct gb_svc *svc = gb_connection_get_data(connection);
926 	int ret;
927 
928 	/*
929 	 * XXX This is a hack/work-around to reconfigure the APBridgeA-Switch
930 	 * link to PWM G2, 1 Lane, Slow Auto, so that it has sufficient
931 	 * bandwidth for 3 audio streams plus boot-over-UniPro of a hot-plugged
932 	 * module.
933 	 *
934 	 * The code should be removed once SW-2217, Heuristic for UniPro
935 	 * Power Mode Changes is resolved.
936 	 */
937 	ret = gb_svc_intf_set_power_mode(svc, svc->ap_intf_id,
938 					 GB_SVC_UNIPRO_HS_SERIES_A,
939 					 GB_SVC_UNIPRO_SLOW_AUTO_MODE,
940 					 2, 1,
941 					 GB_SVC_SMALL_AMPLITUDE,
942 					 GB_SVC_NO_DE_EMPHASIS,
943 					 GB_SVC_UNIPRO_SLOW_AUTO_MODE,
944 					 2, 1,
945 					 0, 0,
946 					 NULL, NULL);
947 
948 	if (ret)
949 		dev_warn(&svc->dev,
950 			 "power mode change failed on AP to switch link: %d\n",
951 			 ret);
952 }
953 
954 static void gb_svc_process_module_inserted(struct gb_operation *operation)
955 {
956 	struct gb_svc_module_inserted_request *request;
957 	struct gb_connection *connection = operation->connection;
958 	struct gb_svc *svc = gb_connection_get_data(connection);
959 	struct gb_host_device *hd = svc->hd;
960 	struct gb_module *module;
961 	size_t num_interfaces;
962 	u8 module_id;
963 	u16 flags;
964 	int ret;
965 
966 	/* The request message size has already been verified. */
967 	request = operation->request->payload;
968 	module_id = request->primary_intf_id;
969 	num_interfaces = request->intf_count;
970 	flags = le16_to_cpu(request->flags);
971 
972 	dev_dbg(&svc->dev, "%s - id = %u, num_interfaces = %zu, flags = 0x%04x\n",
973 		__func__, module_id, num_interfaces, flags);
974 
975 	if (flags & GB_SVC_MODULE_INSERTED_FLAG_NO_PRIMARY) {
976 		dev_warn(&svc->dev, "no primary interface detected on module %u\n",
977 			 module_id);
978 	}
979 
980 	module = gb_svc_module_lookup(svc, module_id);
981 	if (module) {
982 		dev_warn(&svc->dev, "unexpected module-inserted event %u\n",
983 			 module_id);
984 		return;
985 	}
986 
987 	module = gb_module_create(hd, module_id, num_interfaces);
988 	if (!module) {
989 		dev_err(&svc->dev, "failed to create module\n");
990 		return;
991 	}
992 
993 	ret = gb_module_add(module);
994 	if (ret) {
995 		gb_module_put(module);
996 		return;
997 	}
998 
999 	list_add(&module->hd_node, &hd->modules);
1000 }
1001 
1002 static void gb_svc_process_module_removed(struct gb_operation *operation)
1003 {
1004 	struct gb_svc_module_removed_request *request;
1005 	struct gb_connection *connection = operation->connection;
1006 	struct gb_svc *svc = gb_connection_get_data(connection);
1007 	struct gb_module *module;
1008 	u8 module_id;
1009 
1010 	/* The request message size has already been verified. */
1011 	request = operation->request->payload;
1012 	module_id = request->primary_intf_id;
1013 
1014 	dev_dbg(&svc->dev, "%s - id = %u\n", __func__, module_id);
1015 
1016 	module = gb_svc_module_lookup(svc, module_id);
1017 	if (!module) {
1018 		dev_warn(&svc->dev, "unexpected module-removed event %u\n",
1019 			 module_id);
1020 		return;
1021 	}
1022 
1023 	module->disconnected = true;
1024 
1025 	gb_module_del(module);
1026 	list_del(&module->hd_node);
1027 	gb_module_put(module);
1028 }
1029 
1030 static void gb_svc_process_intf_oops(struct gb_operation *operation)
1031 {
1032 	struct gb_svc_intf_oops_request *request;
1033 	struct gb_connection *connection = operation->connection;
1034 	struct gb_svc *svc = gb_connection_get_data(connection);
1035 	struct gb_interface *intf;
1036 	u8 intf_id;
1037 	u8 reason;
1038 
1039 	/* The request message size has already been verified. */
1040 	request = operation->request->payload;
1041 	intf_id = request->intf_id;
1042 	reason = request->reason;
1043 
1044 	intf = gb_svc_interface_lookup(svc, intf_id);
1045 	if (!intf) {
1046 		dev_warn(&svc->dev, "unexpected interface-oops event %u\n",
1047 			 intf_id);
1048 		return;
1049 	}
1050 
1051 	dev_info(&svc->dev, "Deactivating interface %u, interface oops reason = %u\n",
1052 		 intf_id, reason);
1053 
1054 	mutex_lock(&intf->mutex);
1055 	intf->disconnected = true;
1056 	gb_interface_disable(intf);
1057 	gb_interface_deactivate(intf);
1058 	mutex_unlock(&intf->mutex);
1059 }
1060 
1061 static void gb_svc_process_intf_mailbox_event(struct gb_operation *operation)
1062 {
1063 	struct gb_svc_intf_mailbox_event_request *request;
1064 	struct gb_connection *connection = operation->connection;
1065 	struct gb_svc *svc = gb_connection_get_data(connection);
1066 	struct gb_interface *intf;
1067 	u8 intf_id;
1068 	u16 result_code;
1069 	u32 mailbox;
1070 
1071 	/* The request message size has already been verified. */
1072 	request = operation->request->payload;
1073 	intf_id = request->intf_id;
1074 	result_code = le16_to_cpu(request->result_code);
1075 	mailbox = le32_to_cpu(request->mailbox);
1076 
1077 	dev_dbg(&svc->dev, "%s - id = %u, result = 0x%04x, mailbox = 0x%08x\n",
1078 		__func__, intf_id, result_code, mailbox);
1079 
1080 	intf = gb_svc_interface_lookup(svc, intf_id);
1081 	if (!intf) {
1082 		dev_warn(&svc->dev, "unexpected mailbox event %u\n", intf_id);
1083 		return;
1084 	}
1085 
1086 	gb_interface_mailbox_event(intf, result_code, mailbox);
1087 }
1088 
1089 static void gb_svc_process_deferred_request(struct work_struct *work)
1090 {
1091 	struct gb_svc_deferred_request *dr;
1092 	struct gb_operation *operation;
1093 	struct gb_svc *svc;
1094 	u8 type;
1095 
1096 	dr = container_of(work, struct gb_svc_deferred_request, work);
1097 	operation = dr->operation;
1098 	svc = gb_connection_get_data(operation->connection);
1099 	type = operation->request->header->type;
1100 
1101 	switch (type) {
1102 	case GB_SVC_TYPE_SVC_HELLO:
1103 		gb_svc_process_hello_deferred(operation);
1104 		break;
1105 	case GB_SVC_TYPE_MODULE_INSERTED:
1106 		gb_svc_process_module_inserted(operation);
1107 		break;
1108 	case GB_SVC_TYPE_MODULE_REMOVED:
1109 		gb_svc_process_module_removed(operation);
1110 		break;
1111 	case GB_SVC_TYPE_INTF_MAILBOX_EVENT:
1112 		gb_svc_process_intf_mailbox_event(operation);
1113 		break;
1114 	case GB_SVC_TYPE_INTF_OOPS:
1115 		gb_svc_process_intf_oops(operation);
1116 		break;
1117 	default:
1118 		dev_err(&svc->dev, "bad deferred request type: 0x%02x\n", type);
1119 	}
1120 
1121 	gb_operation_put(operation);
1122 	kfree(dr);
1123 }
1124 
1125 static int gb_svc_queue_deferred_request(struct gb_operation *operation)
1126 {
1127 	struct gb_svc *svc = gb_connection_get_data(operation->connection);
1128 	struct gb_svc_deferred_request *dr;
1129 
1130 	dr = kmalloc(sizeof(*dr), GFP_KERNEL);
1131 	if (!dr)
1132 		return -ENOMEM;
1133 
1134 	gb_operation_get(operation);
1135 
1136 	dr->operation = operation;
1137 	INIT_WORK(&dr->work, gb_svc_process_deferred_request);
1138 
1139 	queue_work(svc->wq, &dr->work);
1140 
1141 	return 0;
1142 }
1143 
1144 static int gb_svc_intf_reset_recv(struct gb_operation *op)
1145 {
1146 	struct gb_svc *svc = gb_connection_get_data(op->connection);
1147 	struct gb_message *request = op->request;
1148 	struct gb_svc_intf_reset_request *reset;
1149 
1150 	if (request->payload_size < sizeof(*reset)) {
1151 		dev_warn(&svc->dev, "short reset request received (%zu < %zu)\n",
1152 			 request->payload_size, sizeof(*reset));
1153 		return -EINVAL;
1154 	}
1155 	reset = request->payload;
1156 
1157 	/* FIXME Reset the interface here */
1158 
1159 	return 0;
1160 }
1161 
1162 static int gb_svc_module_inserted_recv(struct gb_operation *op)
1163 {
1164 	struct gb_svc *svc = gb_connection_get_data(op->connection);
1165 	struct gb_svc_module_inserted_request *request;
1166 
1167 	if (op->request->payload_size < sizeof(*request)) {
1168 		dev_warn(&svc->dev, "short module-inserted request received (%zu < %zu)\n",
1169 			 op->request->payload_size, sizeof(*request));
1170 		return -EINVAL;
1171 	}
1172 
1173 	request = op->request->payload;
1174 
1175 	dev_dbg(&svc->dev, "%s - id = %u\n", __func__,
1176 		request->primary_intf_id);
1177 
1178 	return gb_svc_queue_deferred_request(op);
1179 }
1180 
1181 static int gb_svc_module_removed_recv(struct gb_operation *op)
1182 {
1183 	struct gb_svc *svc = gb_connection_get_data(op->connection);
1184 	struct gb_svc_module_removed_request *request;
1185 
1186 	if (op->request->payload_size < sizeof(*request)) {
1187 		dev_warn(&svc->dev, "short module-removed request received (%zu < %zu)\n",
1188 			 op->request->payload_size, sizeof(*request));
1189 		return -EINVAL;
1190 	}
1191 
1192 	request = op->request->payload;
1193 
1194 	dev_dbg(&svc->dev, "%s - id = %u\n", __func__,
1195 		request->primary_intf_id);
1196 
1197 	return gb_svc_queue_deferred_request(op);
1198 }
1199 
1200 static int gb_svc_intf_oops_recv(struct gb_operation *op)
1201 {
1202 	struct gb_svc *svc = gb_connection_get_data(op->connection);
1203 	struct gb_svc_intf_oops_request *request;
1204 
1205 	if (op->request->payload_size < sizeof(*request)) {
1206 		dev_warn(&svc->dev, "short intf-oops request received (%zu < %zu)\n",
1207 			 op->request->payload_size, sizeof(*request));
1208 		return -EINVAL;
1209 	}
1210 
1211 	return gb_svc_queue_deferred_request(op);
1212 }
1213 
1214 static int gb_svc_intf_mailbox_event_recv(struct gb_operation *op)
1215 {
1216 	struct gb_svc *svc = gb_connection_get_data(op->connection);
1217 	struct gb_svc_intf_mailbox_event_request *request;
1218 
1219 	if (op->request->payload_size < sizeof(*request)) {
1220 		dev_warn(&svc->dev, "short mailbox request received (%zu < %zu)\n",
1221 			 op->request->payload_size, sizeof(*request));
1222 		return -EINVAL;
1223 	}
1224 
1225 	request = op->request->payload;
1226 
1227 	dev_dbg(&svc->dev, "%s - id = %u\n", __func__, request->intf_id);
1228 
1229 	return gb_svc_queue_deferred_request(op);
1230 }
1231 
1232 static int gb_svc_request_handler(struct gb_operation *op)
1233 {
1234 	struct gb_connection *connection = op->connection;
1235 	struct gb_svc *svc = gb_connection_get_data(connection);
1236 	u8 type = op->type;
1237 	int ret = 0;
1238 
1239 	/*
1240 	 * SVC requests need to follow a specific order (at least initially) and
1241 	 * below code takes care of enforcing that. The expected order is:
1242 	 * - PROTOCOL_VERSION
1243 	 * - SVC_HELLO
1244 	 * - Any other request, but the earlier two.
1245 	 *
1246 	 * Incoming requests are guaranteed to be serialized and so we don't
1247 	 * need to protect 'state' for any races.
1248 	 */
1249 	switch (type) {
1250 	case GB_SVC_TYPE_PROTOCOL_VERSION:
1251 		if (svc->state != GB_SVC_STATE_RESET)
1252 			ret = -EINVAL;
1253 		break;
1254 	case GB_SVC_TYPE_SVC_HELLO:
1255 		if (svc->state != GB_SVC_STATE_PROTOCOL_VERSION)
1256 			ret = -EINVAL;
1257 		break;
1258 	default:
1259 		if (svc->state != GB_SVC_STATE_SVC_HELLO)
1260 			ret = -EINVAL;
1261 		break;
1262 	}
1263 
1264 	if (ret) {
1265 		dev_warn(&svc->dev, "unexpected request 0x%02x received (state %u)\n",
1266 			 type, svc->state);
1267 		return ret;
1268 	}
1269 
1270 	switch (type) {
1271 	case GB_SVC_TYPE_PROTOCOL_VERSION:
1272 		ret = gb_svc_version_request(op);
1273 		if (!ret)
1274 			svc->state = GB_SVC_STATE_PROTOCOL_VERSION;
1275 		return ret;
1276 	case GB_SVC_TYPE_SVC_HELLO:
1277 		ret = gb_svc_hello(op);
1278 		if (!ret)
1279 			svc->state = GB_SVC_STATE_SVC_HELLO;
1280 		return ret;
1281 	case GB_SVC_TYPE_INTF_RESET:
1282 		return gb_svc_intf_reset_recv(op);
1283 	case GB_SVC_TYPE_MODULE_INSERTED:
1284 		return gb_svc_module_inserted_recv(op);
1285 	case GB_SVC_TYPE_MODULE_REMOVED:
1286 		return gb_svc_module_removed_recv(op);
1287 	case GB_SVC_TYPE_INTF_MAILBOX_EVENT:
1288 		return gb_svc_intf_mailbox_event_recv(op);
1289 	case GB_SVC_TYPE_INTF_OOPS:
1290 		return gb_svc_intf_oops_recv(op);
1291 	default:
1292 		dev_warn(&svc->dev, "unsupported request 0x%02x\n", type);
1293 		return -EINVAL;
1294 	}
1295 }
1296 
1297 static void gb_svc_release(struct device *dev)
1298 {
1299 	struct gb_svc *svc = to_gb_svc(dev);
1300 
1301 	if (svc->connection)
1302 		gb_connection_destroy(svc->connection);
1303 	ida_destroy(&svc->device_id_map);
1304 	destroy_workqueue(svc->wq);
1305 	kfree(svc);
1306 }
1307 
1308 const struct device_type greybus_svc_type = {
1309 	.name		= "greybus_svc",
1310 	.release	= gb_svc_release,
1311 };
1312 
1313 struct gb_svc *gb_svc_create(struct gb_host_device *hd)
1314 {
1315 	struct gb_svc *svc;
1316 
1317 	svc = kzalloc(sizeof(*svc), GFP_KERNEL);
1318 	if (!svc)
1319 		return NULL;
1320 
1321 	svc->wq = alloc_ordered_workqueue("%s:svc", 0, dev_name(&hd->dev));
1322 	if (!svc->wq) {
1323 		kfree(svc);
1324 		return NULL;
1325 	}
1326 
1327 	svc->dev.parent = &hd->dev;
1328 	svc->dev.bus = &greybus_bus_type;
1329 	svc->dev.type = &greybus_svc_type;
1330 	svc->dev.groups = svc_groups;
1331 	svc->dev.dma_mask = svc->dev.parent->dma_mask;
1332 	device_initialize(&svc->dev);
1333 
1334 	dev_set_name(&svc->dev, "%d-svc", hd->bus_id);
1335 
1336 	ida_init(&svc->device_id_map);
1337 	svc->state = GB_SVC_STATE_RESET;
1338 	svc->hd = hd;
1339 
1340 	svc->connection = gb_connection_create_static(hd, GB_SVC_CPORT_ID,
1341 						      gb_svc_request_handler);
1342 	if (IS_ERR(svc->connection)) {
1343 		dev_err(&svc->dev, "failed to create connection: %ld\n",
1344 			PTR_ERR(svc->connection));
1345 		goto err_put_device;
1346 	}
1347 
1348 	gb_connection_set_data(svc->connection, svc);
1349 
1350 	return svc;
1351 
1352 err_put_device:
1353 	put_device(&svc->dev);
1354 	return NULL;
1355 }
1356 
1357 int gb_svc_add(struct gb_svc *svc)
1358 {
1359 	int ret;
1360 
1361 	/*
1362 	 * The SVC protocol is currently driven by the SVC, so the SVC device
1363 	 * is added from the connection request handler when enough
1364 	 * information has been received.
1365 	 */
1366 	ret = gb_connection_enable(svc->connection);
1367 	if (ret)
1368 		return ret;
1369 
1370 	return 0;
1371 }
1372 
1373 static void gb_svc_remove_modules(struct gb_svc *svc)
1374 {
1375 	struct gb_host_device *hd = svc->hd;
1376 	struct gb_module *module, *tmp;
1377 
1378 	list_for_each_entry_safe(module, tmp, &hd->modules, hd_node) {
1379 		gb_module_del(module);
1380 		list_del(&module->hd_node);
1381 		gb_module_put(module);
1382 	}
1383 }
1384 
1385 void gb_svc_del(struct gb_svc *svc)
1386 {
1387 	gb_connection_disable_rx(svc->connection);
1388 
1389 	/*
1390 	 * The SVC device may have been registered from the request handler.
1391 	 */
1392 	if (device_is_registered(&svc->dev)) {
1393 		gb_svc_debugfs_exit(svc);
1394 		gb_svc_watchdog_destroy(svc);
1395 		device_del(&svc->dev);
1396 	}
1397 
1398 	flush_workqueue(svc->wq);
1399 
1400 	gb_svc_remove_modules(svc);
1401 
1402 	gb_connection_disable(svc->connection);
1403 }
1404 
1405 void gb_svc_put(struct gb_svc *svc)
1406 {
1407 	put_device(&svc->dev);
1408 }
1409