xref: /linux/drivers/greybus/svc.c (revision 0c82fd9609a1e4bf1db84b0fd56bc3b2773da179)
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 #include <linux/string_choices.h>
14 
15 #define SVC_INTF_EJECT_TIMEOUT		9000
16 #define SVC_INTF_ACTIVATE_TIMEOUT	6000
17 #define SVC_INTF_RESUME_TIMEOUT		3000
18 
19 struct gb_svc_deferred_request {
20 	struct work_struct work;
21 	struct gb_operation *operation;
22 };
23 
24 static int gb_svc_queue_deferred_request(struct gb_operation *operation);
25 
26 static ssize_t endo_id_show(struct device *dev,
27 			    struct device_attribute *attr, char *buf)
28 {
29 	struct gb_svc *svc = to_gb_svc(dev);
30 
31 	return sprintf(buf, "0x%04x\n", svc->endo_id);
32 }
33 static DEVICE_ATTR_RO(endo_id);
34 
35 static ssize_t ap_intf_id_show(struct device *dev,
36 			       struct device_attribute *attr, char *buf)
37 {
38 	struct gb_svc *svc = to_gb_svc(dev);
39 
40 	return sprintf(buf, "%u\n", svc->ap_intf_id);
41 }
42 static DEVICE_ATTR_RO(ap_intf_id);
43 
44 // FIXME
45 // This is a hack, we need to do this "right" and clean the interface up
46 // properly, not just forcibly yank the thing out of the system and hope for the
47 // best.  But for now, people want their modules to come out without having to
48 // throw the thing to the ground or get out a screwdriver.
49 static ssize_t intf_eject_store(struct device *dev,
50 				struct device_attribute *attr, const char *buf,
51 				size_t len)
52 {
53 	struct gb_svc *svc = to_gb_svc(dev);
54 	unsigned short intf_id;
55 	int ret;
56 
57 	ret = kstrtou16(buf, 10, &intf_id);
58 	if (ret < 0)
59 		return ret;
60 
61 	dev_warn(dev, "Forcibly trying to eject interface %d\n", intf_id);
62 
63 	ret = gb_svc_intf_eject(svc, intf_id);
64 	if (ret < 0)
65 		return ret;
66 
67 	return len;
68 }
69 static DEVICE_ATTR_WO(intf_eject);
70 
71 static ssize_t watchdog_show(struct device *dev, struct device_attribute *attr,
72 			     char *buf)
73 {
74 	struct gb_svc *svc = to_gb_svc(dev);
75 
76 	return sprintf(buf, "%s\n",
77 		       str_enabled_disabled(gb_svc_watchdog_enabled(svc)));
78 }
79 
80 static ssize_t watchdog_store(struct device *dev,
81 			      struct device_attribute *attr, const char *buf,
82 			      size_t len)
83 {
84 	struct gb_svc *svc = to_gb_svc(dev);
85 	int retval;
86 	bool user_request;
87 
88 	retval = kstrtobool(buf, &user_request);
89 	if (retval)
90 		return retval;
91 
92 	if (user_request)
93 		retval = gb_svc_watchdog_enable(svc);
94 	else
95 		retval = gb_svc_watchdog_disable(svc);
96 	if (retval)
97 		return retval;
98 	return len;
99 }
100 static DEVICE_ATTR_RW(watchdog);
101 
102 static ssize_t watchdog_action_show(struct device *dev,
103 				    struct device_attribute *attr, char *buf)
104 {
105 	struct gb_svc *svc = to_gb_svc(dev);
106 
107 	if (svc->action == GB_SVC_WATCHDOG_BITE_PANIC_KERNEL)
108 		return sprintf(buf, "panic\n");
109 	else if (svc->action == GB_SVC_WATCHDOG_BITE_RESET_UNIPRO)
110 		return sprintf(buf, "reset\n");
111 
112 	return -EINVAL;
113 }
114 
115 static ssize_t watchdog_action_store(struct device *dev,
116 				     struct device_attribute *attr,
117 				     const char *buf, size_t len)
118 {
119 	struct gb_svc *svc = to_gb_svc(dev);
120 
121 	if (sysfs_streq(buf, "panic"))
122 		svc->action = GB_SVC_WATCHDOG_BITE_PANIC_KERNEL;
123 	else if (sysfs_streq(buf, "reset"))
124 		svc->action = GB_SVC_WATCHDOG_BITE_RESET_UNIPRO;
125 	else
126 		return -EINVAL;
127 
128 	return len;
129 }
130 static DEVICE_ATTR_RW(watchdog_action);
131 
132 static int gb_svc_pwrmon_rail_count_get(struct gb_svc *svc, u8 *value)
133 {
134 	struct gb_svc_pwrmon_rail_count_get_response response;
135 	int ret;
136 
137 	ret = gb_operation_sync(svc->connection,
138 				GB_SVC_TYPE_PWRMON_RAIL_COUNT_GET, NULL, 0,
139 				&response, sizeof(response));
140 	if (ret) {
141 		dev_err(&svc->dev, "failed to get rail count: %d\n", ret);
142 		return ret;
143 	}
144 
145 	*value = response.rail_count;
146 
147 	return 0;
148 }
149 
150 static int gb_svc_pwrmon_rail_names_get(struct gb_svc *svc,
151 		struct gb_svc_pwrmon_rail_names_get_response *response,
152 		size_t bufsize)
153 {
154 	int ret;
155 
156 	ret = gb_operation_sync(svc->connection,
157 				GB_SVC_TYPE_PWRMON_RAIL_NAMES_GET, NULL, 0,
158 				response, bufsize);
159 	if (ret) {
160 		dev_err(&svc->dev, "failed to get rail names: %d\n", ret);
161 		return ret;
162 	}
163 
164 	if (response->status != GB_SVC_OP_SUCCESS) {
165 		dev_err(&svc->dev,
166 			"SVC error while getting rail names: %u\n",
167 			response->status);
168 		return -EREMOTEIO;
169 	}
170 
171 	return 0;
172 }
173 
174 static int gb_svc_pwrmon_sample_get(struct gb_svc *svc, u8 rail_id,
175 				    u8 measurement_type, u32 *value)
176 {
177 	struct gb_svc_pwrmon_sample_get_request request;
178 	struct gb_svc_pwrmon_sample_get_response response;
179 	int ret;
180 
181 	request.rail_id = rail_id;
182 	request.measurement_type = measurement_type;
183 
184 	ret = gb_operation_sync(svc->connection, GB_SVC_TYPE_PWRMON_SAMPLE_GET,
185 				&request, sizeof(request),
186 				&response, sizeof(response));
187 	if (ret) {
188 		dev_err(&svc->dev, "failed to get rail sample: %d\n", ret);
189 		return ret;
190 	}
191 
192 	if (response.result) {
193 		dev_err(&svc->dev,
194 			"UniPro error while getting rail power sample (%d %d): %d\n",
195 			rail_id, measurement_type, response.result);
196 		switch (response.result) {
197 		case GB_SVC_PWRMON_GET_SAMPLE_INVAL:
198 			return -EINVAL;
199 		case GB_SVC_PWRMON_GET_SAMPLE_NOSUPP:
200 			return -ENOMSG;
201 		default:
202 			return -EREMOTEIO;
203 		}
204 	}
205 
206 	*value = le32_to_cpu(response.measurement);
207 
208 	return 0;
209 }
210 
211 int gb_svc_pwrmon_intf_sample_get(struct gb_svc *svc, u8 intf_id,
212 				  u8 measurement_type, u32 *value)
213 {
214 	struct gb_svc_pwrmon_intf_sample_get_request request;
215 	struct gb_svc_pwrmon_intf_sample_get_response response;
216 	int ret;
217 
218 	request.intf_id = intf_id;
219 	request.measurement_type = measurement_type;
220 
221 	ret = gb_operation_sync(svc->connection,
222 				GB_SVC_TYPE_PWRMON_INTF_SAMPLE_GET,
223 				&request, sizeof(request),
224 				&response, sizeof(response));
225 	if (ret) {
226 		dev_err(&svc->dev, "failed to get intf sample: %d\n", ret);
227 		return ret;
228 	}
229 
230 	if (response.result) {
231 		dev_err(&svc->dev,
232 			"UniPro error while getting intf power sample (%d %d): %d\n",
233 			intf_id, measurement_type, response.result);
234 		switch (response.result) {
235 		case GB_SVC_PWRMON_GET_SAMPLE_INVAL:
236 			return -EINVAL;
237 		case GB_SVC_PWRMON_GET_SAMPLE_NOSUPP:
238 			return -ENOMSG;
239 		default:
240 			return -EREMOTEIO;
241 		}
242 	}
243 
244 	*value = le32_to_cpu(response.measurement);
245 
246 	return 0;
247 }
248 
249 static struct attribute *svc_attrs[] = {
250 	&dev_attr_endo_id.attr,
251 	&dev_attr_ap_intf_id.attr,
252 	&dev_attr_intf_eject.attr,
253 	&dev_attr_watchdog.attr,
254 	&dev_attr_watchdog_action.attr,
255 	NULL,
256 };
257 ATTRIBUTE_GROUPS(svc);
258 
259 int gb_svc_intf_device_id(struct gb_svc *svc, u8 intf_id, u8 device_id)
260 {
261 	struct gb_svc_intf_device_id_request request;
262 
263 	request.intf_id = intf_id;
264 	request.device_id = device_id;
265 
266 	return gb_operation_sync(svc->connection, GB_SVC_TYPE_INTF_DEVICE_ID,
267 				 &request, sizeof(request), NULL, 0);
268 }
269 
270 int gb_svc_intf_eject(struct gb_svc *svc, u8 intf_id)
271 {
272 	struct gb_svc_intf_eject_request request;
273 	int ret;
274 
275 	request.intf_id = intf_id;
276 
277 	/*
278 	 * The pulse width for module release in svc is long so we need to
279 	 * increase the timeout so the operation will not return to soon.
280 	 */
281 	ret = gb_operation_sync_timeout(svc->connection,
282 					GB_SVC_TYPE_INTF_EJECT, &request,
283 					sizeof(request), NULL, 0,
284 					SVC_INTF_EJECT_TIMEOUT);
285 	if (ret) {
286 		dev_err(&svc->dev, "failed to eject interface %u\n", intf_id);
287 		return ret;
288 	}
289 
290 	return 0;
291 }
292 
293 int gb_svc_intf_vsys_set(struct gb_svc *svc, u8 intf_id, bool enable)
294 {
295 	struct gb_svc_intf_vsys_request request;
296 	struct gb_svc_intf_vsys_response response;
297 	int type, ret;
298 
299 	request.intf_id = intf_id;
300 
301 	if (enable)
302 		type = GB_SVC_TYPE_INTF_VSYS_ENABLE;
303 	else
304 		type = GB_SVC_TYPE_INTF_VSYS_DISABLE;
305 
306 	ret = gb_operation_sync(svc->connection, type,
307 				&request, sizeof(request),
308 				&response, sizeof(response));
309 	if (ret < 0)
310 		return ret;
311 	if (response.result_code != GB_SVC_INTF_VSYS_OK)
312 		return -EREMOTEIO;
313 	return 0;
314 }
315 
316 int gb_svc_intf_refclk_set(struct gb_svc *svc, u8 intf_id, bool enable)
317 {
318 	struct gb_svc_intf_refclk_request request;
319 	struct gb_svc_intf_refclk_response response;
320 	int type, ret;
321 
322 	request.intf_id = intf_id;
323 
324 	if (enable)
325 		type = GB_SVC_TYPE_INTF_REFCLK_ENABLE;
326 	else
327 		type = GB_SVC_TYPE_INTF_REFCLK_DISABLE;
328 
329 	ret = gb_operation_sync(svc->connection, type,
330 				&request, sizeof(request),
331 				&response, sizeof(response));
332 	if (ret < 0)
333 		return ret;
334 	if (response.result_code != GB_SVC_INTF_REFCLK_OK)
335 		return -EREMOTEIO;
336 	return 0;
337 }
338 
339 int gb_svc_intf_unipro_set(struct gb_svc *svc, u8 intf_id, bool enable)
340 {
341 	struct gb_svc_intf_unipro_request request;
342 	struct gb_svc_intf_unipro_response response;
343 	int type, ret;
344 
345 	request.intf_id = intf_id;
346 
347 	if (enable)
348 		type = GB_SVC_TYPE_INTF_UNIPRO_ENABLE;
349 	else
350 		type = GB_SVC_TYPE_INTF_UNIPRO_DISABLE;
351 
352 	ret = gb_operation_sync(svc->connection, type,
353 				&request, sizeof(request),
354 				&response, sizeof(response));
355 	if (ret < 0)
356 		return ret;
357 	if (response.result_code != GB_SVC_INTF_UNIPRO_OK)
358 		return -EREMOTEIO;
359 	return 0;
360 }
361 
362 int gb_svc_intf_activate(struct gb_svc *svc, u8 intf_id, u8 *intf_type)
363 {
364 	struct gb_svc_intf_activate_request request;
365 	struct gb_svc_intf_activate_response response;
366 	int ret;
367 
368 	request.intf_id = intf_id;
369 
370 	ret = gb_operation_sync_timeout(svc->connection,
371 					GB_SVC_TYPE_INTF_ACTIVATE,
372 					&request, sizeof(request),
373 					&response, sizeof(response),
374 					SVC_INTF_ACTIVATE_TIMEOUT);
375 	if (ret < 0)
376 		return ret;
377 	if (response.status != GB_SVC_OP_SUCCESS) {
378 		dev_err(&svc->dev, "failed to activate interface %u: %u\n",
379 			intf_id, response.status);
380 		return -EREMOTEIO;
381 	}
382 
383 	*intf_type = response.intf_type;
384 
385 	return 0;
386 }
387 
388 int gb_svc_intf_resume(struct gb_svc *svc, u8 intf_id)
389 {
390 	struct gb_svc_intf_resume_request request;
391 	struct gb_svc_intf_resume_response response;
392 	int ret;
393 
394 	request.intf_id = intf_id;
395 
396 	ret = gb_operation_sync_timeout(svc->connection,
397 					GB_SVC_TYPE_INTF_RESUME,
398 					&request, sizeof(request),
399 					&response, sizeof(response),
400 					SVC_INTF_RESUME_TIMEOUT);
401 	if (ret < 0) {
402 		dev_err(&svc->dev, "failed to send interface resume %u: %d\n",
403 			intf_id, ret);
404 		return ret;
405 	}
406 
407 	if (response.status != GB_SVC_OP_SUCCESS) {
408 		dev_err(&svc->dev, "failed to resume interface %u: %u\n",
409 			intf_id, response.status);
410 		return -EREMOTEIO;
411 	}
412 
413 	return 0;
414 }
415 
416 int gb_svc_dme_peer_get(struct gb_svc *svc, u8 intf_id, u16 attr, u16 selector,
417 			u32 *value)
418 {
419 	struct gb_svc_dme_peer_get_request request;
420 	struct gb_svc_dme_peer_get_response response;
421 	u16 result;
422 	int ret;
423 
424 	request.intf_id = intf_id;
425 	request.attr = cpu_to_le16(attr);
426 	request.selector = cpu_to_le16(selector);
427 
428 	ret = gb_operation_sync(svc->connection, GB_SVC_TYPE_DME_PEER_GET,
429 				&request, sizeof(request),
430 				&response, sizeof(response));
431 	if (ret) {
432 		dev_err(&svc->dev, "failed to get DME attribute (%u 0x%04x %u): %d\n",
433 			intf_id, attr, selector, ret);
434 		return ret;
435 	}
436 
437 	result = le16_to_cpu(response.result_code);
438 	if (result) {
439 		dev_err(&svc->dev, "UniPro error while getting DME attribute (%u 0x%04x %u): %u\n",
440 			intf_id, attr, selector, result);
441 		return -EREMOTEIO;
442 	}
443 
444 	if (value)
445 		*value = le32_to_cpu(response.attr_value);
446 
447 	return 0;
448 }
449 
450 int gb_svc_dme_peer_set(struct gb_svc *svc, u8 intf_id, u16 attr, u16 selector,
451 			u32 value)
452 {
453 	struct gb_svc_dme_peer_set_request request;
454 	struct gb_svc_dme_peer_set_response response;
455 	u16 result;
456 	int ret;
457 
458 	request.intf_id = intf_id;
459 	request.attr = cpu_to_le16(attr);
460 	request.selector = cpu_to_le16(selector);
461 	request.value = cpu_to_le32(value);
462 
463 	ret = gb_operation_sync(svc->connection, GB_SVC_TYPE_DME_PEER_SET,
464 				&request, sizeof(request),
465 				&response, sizeof(response));
466 	if (ret) {
467 		dev_err(&svc->dev, "failed to set DME attribute (%u 0x%04x %u %u): %d\n",
468 			intf_id, attr, selector, value, ret);
469 		return ret;
470 	}
471 
472 	result = le16_to_cpu(response.result_code);
473 	if (result) {
474 		dev_err(&svc->dev, "UniPro error while setting DME attribute (%u 0x%04x %u %u): %u\n",
475 			intf_id, attr, selector, value, result);
476 		return -EREMOTEIO;
477 	}
478 
479 	return 0;
480 }
481 
482 int gb_svc_connection_create(struct gb_svc *svc,
483 			     u8 intf1_id, u16 cport1_id,
484 			     u8 intf2_id, u16 cport2_id,
485 			     u8 cport_flags)
486 {
487 	struct gb_svc_conn_create_request request;
488 
489 	request.intf1_id = intf1_id;
490 	request.cport1_id = cpu_to_le16(cport1_id);
491 	request.intf2_id = intf2_id;
492 	request.cport2_id = cpu_to_le16(cport2_id);
493 	request.tc = 0;		/* TC0 */
494 	request.flags = cport_flags;
495 
496 	return gb_operation_sync(svc->connection, GB_SVC_TYPE_CONN_CREATE,
497 				 &request, sizeof(request), NULL, 0);
498 }
499 
500 void gb_svc_connection_destroy(struct gb_svc *svc, u8 intf1_id, u16 cport1_id,
501 			       u8 intf2_id, u16 cport2_id)
502 {
503 	struct gb_svc_conn_destroy_request request;
504 	struct gb_connection *connection = svc->connection;
505 	int ret;
506 
507 	request.intf1_id = intf1_id;
508 	request.cport1_id = cpu_to_le16(cport1_id);
509 	request.intf2_id = intf2_id;
510 	request.cport2_id = cpu_to_le16(cport2_id);
511 
512 	ret = gb_operation_sync(connection, GB_SVC_TYPE_CONN_DESTROY,
513 				&request, sizeof(request), NULL, 0);
514 	if (ret) {
515 		dev_err(&svc->dev, "failed to destroy connection (%u:%u %u:%u): %d\n",
516 			intf1_id, cport1_id, intf2_id, cport2_id, ret);
517 	}
518 }
519 
520 /* Creates bi-directional routes between the devices */
521 int gb_svc_route_create(struct gb_svc *svc, u8 intf1_id, u8 dev1_id,
522 			u8 intf2_id, u8 dev2_id)
523 {
524 	struct gb_svc_route_create_request request;
525 
526 	request.intf1_id = intf1_id;
527 	request.dev1_id = dev1_id;
528 	request.intf2_id = intf2_id;
529 	request.dev2_id = dev2_id;
530 
531 	return gb_operation_sync(svc->connection, GB_SVC_TYPE_ROUTE_CREATE,
532 				 &request, sizeof(request), NULL, 0);
533 }
534 
535 /* Destroys bi-directional routes between the devices */
536 void gb_svc_route_destroy(struct gb_svc *svc, u8 intf1_id, u8 intf2_id)
537 {
538 	struct gb_svc_route_destroy_request request;
539 	int ret;
540 
541 	request.intf1_id = intf1_id;
542 	request.intf2_id = intf2_id;
543 
544 	ret = gb_operation_sync(svc->connection, GB_SVC_TYPE_ROUTE_DESTROY,
545 				&request, sizeof(request), NULL, 0);
546 	if (ret) {
547 		dev_err(&svc->dev, "failed to destroy route (%u %u): %d\n",
548 			intf1_id, intf2_id, ret);
549 	}
550 }
551 
552 int gb_svc_intf_set_power_mode(struct gb_svc *svc, u8 intf_id, u8 hs_series,
553 			       u8 tx_mode, u8 tx_gear, u8 tx_nlanes,
554 			       u8 tx_amplitude, u8 tx_hs_equalizer,
555 			       u8 rx_mode, u8 rx_gear, u8 rx_nlanes,
556 			       u8 flags, u32 quirks,
557 			       struct gb_svc_l2_timer_cfg *local,
558 			       struct gb_svc_l2_timer_cfg *remote)
559 {
560 	struct gb_svc_intf_set_pwrm_request request;
561 	struct gb_svc_intf_set_pwrm_response response;
562 	int ret;
563 	u16 result_code;
564 
565 	memset(&request, 0, sizeof(request));
566 
567 	request.intf_id = intf_id;
568 	request.hs_series = hs_series;
569 	request.tx_mode = tx_mode;
570 	request.tx_gear = tx_gear;
571 	request.tx_nlanes = tx_nlanes;
572 	request.tx_amplitude = tx_amplitude;
573 	request.tx_hs_equalizer = tx_hs_equalizer;
574 	request.rx_mode = rx_mode;
575 	request.rx_gear = rx_gear;
576 	request.rx_nlanes = rx_nlanes;
577 	request.flags = flags;
578 	request.quirks = cpu_to_le32(quirks);
579 	if (local)
580 		request.local_l2timerdata = *local;
581 	if (remote)
582 		request.remote_l2timerdata = *remote;
583 
584 	ret = gb_operation_sync(svc->connection, GB_SVC_TYPE_INTF_SET_PWRM,
585 				&request, sizeof(request),
586 				&response, sizeof(response));
587 	if (ret < 0)
588 		return ret;
589 
590 	result_code = response.result_code;
591 	if (result_code != GB_SVC_SETPWRM_PWR_LOCAL) {
592 		dev_err(&svc->dev, "set power mode = %d\n", result_code);
593 		return -EIO;
594 	}
595 
596 	return 0;
597 }
598 EXPORT_SYMBOL_GPL(gb_svc_intf_set_power_mode);
599 
600 int gb_svc_intf_set_power_mode_hibernate(struct gb_svc *svc, u8 intf_id)
601 {
602 	struct gb_svc_intf_set_pwrm_request request;
603 	struct gb_svc_intf_set_pwrm_response response;
604 	int ret;
605 	u16 result_code;
606 
607 	memset(&request, 0, sizeof(request));
608 
609 	request.intf_id = intf_id;
610 	request.hs_series = GB_SVC_UNIPRO_HS_SERIES_A;
611 	request.tx_mode = GB_SVC_UNIPRO_HIBERNATE_MODE;
612 	request.rx_mode = GB_SVC_UNIPRO_HIBERNATE_MODE;
613 
614 	ret = gb_operation_sync(svc->connection, GB_SVC_TYPE_INTF_SET_PWRM,
615 				&request, sizeof(request),
616 				&response, sizeof(response));
617 	if (ret < 0) {
618 		dev_err(&svc->dev,
619 			"failed to send set power mode operation to interface %u: %d\n",
620 			intf_id, ret);
621 		return ret;
622 	}
623 
624 	result_code = response.result_code;
625 	if (result_code != GB_SVC_SETPWRM_PWR_OK) {
626 		dev_err(&svc->dev,
627 			"failed to hibernate the link for interface %u: %u\n",
628 			intf_id, result_code);
629 		return -EIO;
630 	}
631 
632 	return 0;
633 }
634 
635 int gb_svc_ping(struct gb_svc *svc)
636 {
637 	return gb_operation_sync_timeout(svc->connection, GB_SVC_TYPE_PING,
638 					 NULL, 0, NULL, 0,
639 					 GB_OPERATION_TIMEOUT_DEFAULT * 2);
640 }
641 
642 static int gb_svc_version_request(struct gb_operation *op)
643 {
644 	struct gb_connection *connection = op->connection;
645 	struct gb_svc *svc = gb_connection_get_data(connection);
646 	struct gb_svc_version_request *request;
647 	struct gb_svc_version_response *response;
648 
649 	if (op->request->payload_size < sizeof(*request)) {
650 		dev_err(&svc->dev, "short version request (%zu < %zu)\n",
651 			op->request->payload_size,
652 			sizeof(*request));
653 		return -EINVAL;
654 	}
655 
656 	request = op->request->payload;
657 
658 	if (request->major > GB_SVC_VERSION_MAJOR) {
659 		dev_warn(&svc->dev, "unsupported major version (%u > %u)\n",
660 			 request->major, GB_SVC_VERSION_MAJOR);
661 		return -ENOTSUPP;
662 	}
663 
664 	svc->protocol_major = request->major;
665 	svc->protocol_minor = request->minor;
666 
667 	if (!gb_operation_response_alloc(op, sizeof(*response), GFP_KERNEL))
668 		return -ENOMEM;
669 
670 	response = op->response->payload;
671 	response->major = svc->protocol_major;
672 	response->minor = svc->protocol_minor;
673 
674 	return 0;
675 }
676 
677 static ssize_t pwr_debugfs_voltage_read(struct file *file, char __user *buf,
678 					size_t len, loff_t *offset)
679 {
680 	struct svc_debugfs_pwrmon_rail *pwrmon_rails =
681 		file_inode(file)->i_private;
682 	struct gb_svc *svc = pwrmon_rails->svc;
683 	int ret, desc;
684 	u32 value;
685 	char buff[16];
686 
687 	ret = gb_svc_pwrmon_sample_get(svc, pwrmon_rails->id,
688 				       GB_SVC_PWRMON_TYPE_VOL, &value);
689 	if (ret) {
690 		dev_err(&svc->dev,
691 			"failed to get voltage sample %u: %d\n",
692 			pwrmon_rails->id, ret);
693 		return ret;
694 	}
695 
696 	desc = scnprintf(buff, sizeof(buff), "%u\n", value);
697 
698 	return simple_read_from_buffer(buf, len, offset, buff, desc);
699 }
700 
701 static ssize_t pwr_debugfs_current_read(struct file *file, char __user *buf,
702 					size_t len, loff_t *offset)
703 {
704 	struct svc_debugfs_pwrmon_rail *pwrmon_rails =
705 		file_inode(file)->i_private;
706 	struct gb_svc *svc = pwrmon_rails->svc;
707 	int ret, desc;
708 	u32 value;
709 	char buff[16];
710 
711 	ret = gb_svc_pwrmon_sample_get(svc, pwrmon_rails->id,
712 				       GB_SVC_PWRMON_TYPE_CURR, &value);
713 	if (ret) {
714 		dev_err(&svc->dev,
715 			"failed to get current sample %u: %d\n",
716 			pwrmon_rails->id, ret);
717 		return ret;
718 	}
719 
720 	desc = scnprintf(buff, sizeof(buff), "%u\n", value);
721 
722 	return simple_read_from_buffer(buf, len, offset, buff, desc);
723 }
724 
725 static ssize_t pwr_debugfs_power_read(struct file *file, char __user *buf,
726 				      size_t len, loff_t *offset)
727 {
728 	struct svc_debugfs_pwrmon_rail *pwrmon_rails =
729 		file_inode(file)->i_private;
730 	struct gb_svc *svc = pwrmon_rails->svc;
731 	int ret, desc;
732 	u32 value;
733 	char buff[16];
734 
735 	ret = gb_svc_pwrmon_sample_get(svc, pwrmon_rails->id,
736 				       GB_SVC_PWRMON_TYPE_PWR, &value);
737 	if (ret) {
738 		dev_err(&svc->dev, "failed to get power sample %u: %d\n",
739 			pwrmon_rails->id, ret);
740 		return ret;
741 	}
742 
743 	desc = scnprintf(buff, sizeof(buff), "%u\n", value);
744 
745 	return simple_read_from_buffer(buf, len, offset, buff, desc);
746 }
747 
748 static const struct file_operations pwrmon_debugfs_voltage_fops = {
749 	.read		= pwr_debugfs_voltage_read,
750 };
751 
752 static const struct file_operations pwrmon_debugfs_current_fops = {
753 	.read		= pwr_debugfs_current_read,
754 };
755 
756 static const struct file_operations pwrmon_debugfs_power_fops = {
757 	.read		= pwr_debugfs_power_read,
758 };
759 
760 static void gb_svc_pwrmon_debugfs_init(struct gb_svc *svc)
761 {
762 	int i;
763 	size_t bufsize;
764 	struct dentry *dent;
765 	struct gb_svc_pwrmon_rail_names_get_response *rail_names;
766 	u8 rail_count;
767 
768 	dent = debugfs_create_dir("pwrmon", svc->debugfs_dentry);
769 	if (IS_ERR_OR_NULL(dent))
770 		return;
771 
772 	if (gb_svc_pwrmon_rail_count_get(svc, &rail_count))
773 		goto err_pwrmon_debugfs;
774 
775 	if (!rail_count || rail_count > GB_SVC_PWRMON_MAX_RAIL_COUNT)
776 		goto err_pwrmon_debugfs;
777 
778 	bufsize = sizeof(*rail_names) +
779 		GB_SVC_PWRMON_RAIL_NAME_BUFSIZE * rail_count;
780 
781 	rail_names = kzalloc(bufsize, GFP_KERNEL);
782 	if (!rail_names)
783 		goto err_pwrmon_debugfs;
784 
785 	svc->pwrmon_rails = kcalloc(rail_count, sizeof(*svc->pwrmon_rails),
786 				    GFP_KERNEL);
787 	if (!svc->pwrmon_rails)
788 		goto err_pwrmon_debugfs_free;
789 
790 	if (gb_svc_pwrmon_rail_names_get(svc, rail_names, bufsize))
791 		goto err_pwrmon_debugfs_free;
792 
793 	for (i = 0; i < rail_count; i++) {
794 		struct dentry *dir;
795 		struct svc_debugfs_pwrmon_rail *rail = &svc->pwrmon_rails[i];
796 		char fname[GB_SVC_PWRMON_RAIL_NAME_BUFSIZE];
797 
798 		snprintf(fname, sizeof(fname), "%s",
799 			 (char *)&rail_names->name[i]);
800 
801 		rail->id = i;
802 		rail->svc = svc;
803 
804 		dir = debugfs_create_dir(fname, dent);
805 		debugfs_create_file("voltage_now", 0444, dir, rail,
806 				    &pwrmon_debugfs_voltage_fops);
807 		debugfs_create_file("current_now", 0444, dir, rail,
808 				    &pwrmon_debugfs_current_fops);
809 		debugfs_create_file("power_now", 0444, dir, rail,
810 				    &pwrmon_debugfs_power_fops);
811 	}
812 
813 	kfree(rail_names);
814 	return;
815 
816 err_pwrmon_debugfs_free:
817 	kfree(rail_names);
818 	kfree(svc->pwrmon_rails);
819 	svc->pwrmon_rails = NULL;
820 
821 err_pwrmon_debugfs:
822 	debugfs_remove(dent);
823 }
824 
825 static void gb_svc_debugfs_init(struct gb_svc *svc)
826 {
827 	svc->debugfs_dentry = debugfs_create_dir(dev_name(&svc->dev),
828 						 gb_debugfs_get());
829 	gb_svc_pwrmon_debugfs_init(svc);
830 }
831 
832 static void gb_svc_debugfs_exit(struct gb_svc *svc)
833 {
834 	debugfs_remove_recursive(svc->debugfs_dentry);
835 	kfree(svc->pwrmon_rails);
836 	svc->pwrmon_rails = NULL;
837 }
838 
839 static int gb_svc_hello(struct gb_operation *op)
840 {
841 	struct gb_connection *connection = op->connection;
842 	struct gb_svc *svc = gb_connection_get_data(connection);
843 	struct gb_svc_hello_request *hello_request;
844 	int ret;
845 
846 	if (op->request->payload_size < sizeof(*hello_request)) {
847 		dev_warn(&svc->dev, "short hello request (%zu < %zu)\n",
848 			 op->request->payload_size,
849 			 sizeof(*hello_request));
850 		return -EINVAL;
851 	}
852 
853 	hello_request = op->request->payload;
854 	svc->endo_id = le16_to_cpu(hello_request->endo_id);
855 	svc->ap_intf_id = hello_request->interface_id;
856 
857 	ret = device_add(&svc->dev);
858 	if (ret) {
859 		dev_err(&svc->dev, "failed to register svc device: %d\n", ret);
860 		return ret;
861 	}
862 
863 	ret = gb_svc_watchdog_create(svc);
864 	if (ret) {
865 		dev_err(&svc->dev, "failed to create watchdog: %d\n", ret);
866 		goto err_deregister_svc;
867 	}
868 
869 	/*
870 	 * FIXME: This is a temporary hack to reconfigure the link at HELLO
871 	 * (which abuses the deferred request processing mechanism).
872 	 */
873 	ret = gb_svc_queue_deferred_request(op);
874 	if (ret)
875 		goto err_destroy_watchdog;
876 
877 	gb_svc_debugfs_init(svc);
878 
879 	return 0;
880 
881 err_destroy_watchdog:
882 	gb_svc_watchdog_destroy(svc);
883 err_deregister_svc:
884 	device_del(&svc->dev);
885 
886 	return ret;
887 }
888 
889 static struct gb_interface *gb_svc_interface_lookup(struct gb_svc *svc,
890 						    u8 intf_id)
891 {
892 	struct gb_host_device *hd = svc->hd;
893 	struct gb_module *module;
894 	size_t num_interfaces;
895 	u8 module_id;
896 
897 	list_for_each_entry(module, &hd->modules, hd_node) {
898 		module_id = module->module_id;
899 		num_interfaces = module->num_interfaces;
900 
901 		if (intf_id >= module_id &&
902 		    intf_id < module_id + num_interfaces) {
903 			return module->interfaces[intf_id - module_id];
904 		}
905 	}
906 
907 	return NULL;
908 }
909 
910 static struct gb_module *gb_svc_module_lookup(struct gb_svc *svc, u8 module_id)
911 {
912 	struct gb_host_device *hd = svc->hd;
913 	struct gb_module *module;
914 
915 	list_for_each_entry(module, &hd->modules, hd_node) {
916 		if (module->module_id == module_id)
917 			return module;
918 	}
919 
920 	return NULL;
921 }
922 
923 static void gb_svc_process_hello_deferred(struct gb_operation *operation)
924 {
925 	struct gb_connection *connection = operation->connection;
926 	struct gb_svc *svc = gb_connection_get_data(connection);
927 	int ret;
928 
929 	/*
930 	 * XXX This is a hack/work-around to reconfigure the APBridgeA-Switch
931 	 * link to PWM G2, 1 Lane, Slow Auto, so that it has sufficient
932 	 * bandwidth for 3 audio streams plus boot-over-UniPro of a hot-plugged
933 	 * module.
934 	 *
935 	 * The code should be removed once SW-2217, Heuristic for UniPro
936 	 * Power Mode Changes is resolved.
937 	 */
938 	ret = gb_svc_intf_set_power_mode(svc, svc->ap_intf_id,
939 					 GB_SVC_UNIPRO_HS_SERIES_A,
940 					 GB_SVC_UNIPRO_SLOW_AUTO_MODE,
941 					 2, 1,
942 					 GB_SVC_SMALL_AMPLITUDE,
943 					 GB_SVC_NO_DE_EMPHASIS,
944 					 GB_SVC_UNIPRO_SLOW_AUTO_MODE,
945 					 2, 1,
946 					 0, 0,
947 					 NULL, NULL);
948 
949 	if (ret)
950 		dev_warn(&svc->dev,
951 			 "power mode change failed on AP to switch link: %d\n",
952 			 ret);
953 }
954 
955 static void gb_svc_process_module_inserted(struct gb_operation *operation)
956 {
957 	struct gb_svc_module_inserted_request *request;
958 	struct gb_connection *connection = operation->connection;
959 	struct gb_svc *svc = gb_connection_get_data(connection);
960 	struct gb_host_device *hd = svc->hd;
961 	struct gb_module *module;
962 	size_t num_interfaces;
963 	u8 module_id;
964 	u16 flags;
965 	int ret;
966 
967 	/* The request message size has already been verified. */
968 	request = operation->request->payload;
969 	module_id = request->primary_intf_id;
970 	num_interfaces = request->intf_count;
971 	flags = le16_to_cpu(request->flags);
972 
973 	dev_dbg(&svc->dev, "%s - id = %u, num_interfaces = %zu, flags = 0x%04x\n",
974 		__func__, module_id, num_interfaces, flags);
975 
976 	if (flags & GB_SVC_MODULE_INSERTED_FLAG_NO_PRIMARY) {
977 		dev_warn(&svc->dev, "no primary interface detected on module %u\n",
978 			 module_id);
979 	}
980 
981 	module = gb_svc_module_lookup(svc, module_id);
982 	if (module) {
983 		dev_warn(&svc->dev, "unexpected module-inserted event %u\n",
984 			 module_id);
985 		return;
986 	}
987 
988 	module = gb_module_create(hd, module_id, num_interfaces);
989 	if (!module) {
990 		dev_err(&svc->dev, "failed to create module\n");
991 		return;
992 	}
993 
994 	ret = gb_module_add(module);
995 	if (ret) {
996 		gb_module_put(module);
997 		return;
998 	}
999 
1000 	list_add(&module->hd_node, &hd->modules);
1001 }
1002 
1003 static void gb_svc_process_module_removed(struct gb_operation *operation)
1004 {
1005 	struct gb_svc_module_removed_request *request;
1006 	struct gb_connection *connection = operation->connection;
1007 	struct gb_svc *svc = gb_connection_get_data(connection);
1008 	struct gb_module *module;
1009 	u8 module_id;
1010 
1011 	/* The request message size has already been verified. */
1012 	request = operation->request->payload;
1013 	module_id = request->primary_intf_id;
1014 
1015 	dev_dbg(&svc->dev, "%s - id = %u\n", __func__, module_id);
1016 
1017 	module = gb_svc_module_lookup(svc, module_id);
1018 	if (!module) {
1019 		dev_warn(&svc->dev, "unexpected module-removed event %u\n",
1020 			 module_id);
1021 		return;
1022 	}
1023 
1024 	module->disconnected = true;
1025 
1026 	gb_module_del(module);
1027 	list_del(&module->hd_node);
1028 	gb_module_put(module);
1029 }
1030 
1031 static void gb_svc_process_intf_oops(struct gb_operation *operation)
1032 {
1033 	struct gb_svc_intf_oops_request *request;
1034 	struct gb_connection *connection = operation->connection;
1035 	struct gb_svc *svc = gb_connection_get_data(connection);
1036 	struct gb_interface *intf;
1037 	u8 intf_id;
1038 	u8 reason;
1039 
1040 	/* The request message size has already been verified. */
1041 	request = operation->request->payload;
1042 	intf_id = request->intf_id;
1043 	reason = request->reason;
1044 
1045 	intf = gb_svc_interface_lookup(svc, intf_id);
1046 	if (!intf) {
1047 		dev_warn(&svc->dev, "unexpected interface-oops event %u\n",
1048 			 intf_id);
1049 		return;
1050 	}
1051 
1052 	dev_info(&svc->dev, "Deactivating interface %u, interface oops reason = %u\n",
1053 		 intf_id, reason);
1054 
1055 	mutex_lock(&intf->mutex);
1056 	intf->disconnected = true;
1057 	gb_interface_disable(intf);
1058 	gb_interface_deactivate(intf);
1059 	mutex_unlock(&intf->mutex);
1060 }
1061 
1062 static void gb_svc_process_intf_mailbox_event(struct gb_operation *operation)
1063 {
1064 	struct gb_svc_intf_mailbox_event_request *request;
1065 	struct gb_connection *connection = operation->connection;
1066 	struct gb_svc *svc = gb_connection_get_data(connection);
1067 	struct gb_interface *intf;
1068 	u8 intf_id;
1069 	u16 result_code;
1070 	u32 mailbox;
1071 
1072 	/* The request message size has already been verified. */
1073 	request = operation->request->payload;
1074 	intf_id = request->intf_id;
1075 	result_code = le16_to_cpu(request->result_code);
1076 	mailbox = le32_to_cpu(request->mailbox);
1077 
1078 	dev_dbg(&svc->dev, "%s - id = %u, result = 0x%04x, mailbox = 0x%08x\n",
1079 		__func__, intf_id, result_code, mailbox);
1080 
1081 	intf = gb_svc_interface_lookup(svc, intf_id);
1082 	if (!intf) {
1083 		dev_warn(&svc->dev, "unexpected mailbox event %u\n", intf_id);
1084 		return;
1085 	}
1086 
1087 	gb_interface_mailbox_event(intf, result_code, mailbox);
1088 }
1089 
1090 static void gb_svc_process_deferred_request(struct work_struct *work)
1091 {
1092 	struct gb_svc_deferred_request *dr;
1093 	struct gb_operation *operation;
1094 	struct gb_svc *svc;
1095 	u8 type;
1096 
1097 	dr = container_of(work, struct gb_svc_deferred_request, work);
1098 	operation = dr->operation;
1099 	svc = gb_connection_get_data(operation->connection);
1100 	type = operation->request->header->type;
1101 
1102 	switch (type) {
1103 	case GB_SVC_TYPE_SVC_HELLO:
1104 		gb_svc_process_hello_deferred(operation);
1105 		break;
1106 	case GB_SVC_TYPE_MODULE_INSERTED:
1107 		gb_svc_process_module_inserted(operation);
1108 		break;
1109 	case GB_SVC_TYPE_MODULE_REMOVED:
1110 		gb_svc_process_module_removed(operation);
1111 		break;
1112 	case GB_SVC_TYPE_INTF_MAILBOX_EVENT:
1113 		gb_svc_process_intf_mailbox_event(operation);
1114 		break;
1115 	case GB_SVC_TYPE_INTF_OOPS:
1116 		gb_svc_process_intf_oops(operation);
1117 		break;
1118 	default:
1119 		dev_err(&svc->dev, "bad deferred request type: 0x%02x\n", type);
1120 	}
1121 
1122 	gb_operation_put(operation);
1123 	kfree(dr);
1124 }
1125 
1126 static int gb_svc_queue_deferred_request(struct gb_operation *operation)
1127 {
1128 	struct gb_svc *svc = gb_connection_get_data(operation->connection);
1129 	struct gb_svc_deferred_request *dr;
1130 
1131 	dr = kmalloc(sizeof(*dr), GFP_KERNEL);
1132 	if (!dr)
1133 		return -ENOMEM;
1134 
1135 	gb_operation_get(operation);
1136 
1137 	dr->operation = operation;
1138 	INIT_WORK(&dr->work, gb_svc_process_deferred_request);
1139 
1140 	queue_work(svc->wq, &dr->work);
1141 
1142 	return 0;
1143 }
1144 
1145 static int gb_svc_intf_reset_recv(struct gb_operation *op)
1146 {
1147 	struct gb_svc *svc = gb_connection_get_data(op->connection);
1148 	struct gb_message *request = op->request;
1149 	struct gb_svc_intf_reset_request *reset;
1150 
1151 	if (request->payload_size < sizeof(*reset)) {
1152 		dev_warn(&svc->dev, "short reset request received (%zu < %zu)\n",
1153 			 request->payload_size, sizeof(*reset));
1154 		return -EINVAL;
1155 	}
1156 	reset = request->payload;
1157 
1158 	/* FIXME Reset the interface here */
1159 
1160 	return 0;
1161 }
1162 
1163 static int gb_svc_module_inserted_recv(struct gb_operation *op)
1164 {
1165 	struct gb_svc *svc = gb_connection_get_data(op->connection);
1166 	struct gb_svc_module_inserted_request *request;
1167 
1168 	if (op->request->payload_size < sizeof(*request)) {
1169 		dev_warn(&svc->dev, "short module-inserted request received (%zu < %zu)\n",
1170 			 op->request->payload_size, sizeof(*request));
1171 		return -EINVAL;
1172 	}
1173 
1174 	request = op->request->payload;
1175 
1176 	dev_dbg(&svc->dev, "%s - id = %u\n", __func__,
1177 		request->primary_intf_id);
1178 
1179 	return gb_svc_queue_deferred_request(op);
1180 }
1181 
1182 static int gb_svc_module_removed_recv(struct gb_operation *op)
1183 {
1184 	struct gb_svc *svc = gb_connection_get_data(op->connection);
1185 	struct gb_svc_module_removed_request *request;
1186 
1187 	if (op->request->payload_size < sizeof(*request)) {
1188 		dev_warn(&svc->dev, "short module-removed request received (%zu < %zu)\n",
1189 			 op->request->payload_size, sizeof(*request));
1190 		return -EINVAL;
1191 	}
1192 
1193 	request = op->request->payload;
1194 
1195 	dev_dbg(&svc->dev, "%s - id = %u\n", __func__,
1196 		request->primary_intf_id);
1197 
1198 	return gb_svc_queue_deferred_request(op);
1199 }
1200 
1201 static int gb_svc_intf_oops_recv(struct gb_operation *op)
1202 {
1203 	struct gb_svc *svc = gb_connection_get_data(op->connection);
1204 	struct gb_svc_intf_oops_request *request;
1205 
1206 	if (op->request->payload_size < sizeof(*request)) {
1207 		dev_warn(&svc->dev, "short intf-oops request received (%zu < %zu)\n",
1208 			 op->request->payload_size, sizeof(*request));
1209 		return -EINVAL;
1210 	}
1211 
1212 	return gb_svc_queue_deferred_request(op);
1213 }
1214 
1215 static int gb_svc_intf_mailbox_event_recv(struct gb_operation *op)
1216 {
1217 	struct gb_svc *svc = gb_connection_get_data(op->connection);
1218 	struct gb_svc_intf_mailbox_event_request *request;
1219 
1220 	if (op->request->payload_size < sizeof(*request)) {
1221 		dev_warn(&svc->dev, "short mailbox request received (%zu < %zu)\n",
1222 			 op->request->payload_size, sizeof(*request));
1223 		return -EINVAL;
1224 	}
1225 
1226 	request = op->request->payload;
1227 
1228 	dev_dbg(&svc->dev, "%s - id = %u\n", __func__, request->intf_id);
1229 
1230 	return gb_svc_queue_deferred_request(op);
1231 }
1232 
1233 static int gb_svc_request_handler(struct gb_operation *op)
1234 {
1235 	struct gb_connection *connection = op->connection;
1236 	struct gb_svc *svc = gb_connection_get_data(connection);
1237 	u8 type = op->type;
1238 	int ret = 0;
1239 
1240 	/*
1241 	 * SVC requests need to follow a specific order (at least initially) and
1242 	 * below code takes care of enforcing that. The expected order is:
1243 	 * - PROTOCOL_VERSION
1244 	 * - SVC_HELLO
1245 	 * - Any other request, but the earlier two.
1246 	 *
1247 	 * Incoming requests are guaranteed to be serialized and so we don't
1248 	 * need to protect 'state' for any races.
1249 	 */
1250 	switch (type) {
1251 	case GB_SVC_TYPE_PROTOCOL_VERSION:
1252 		if (svc->state != GB_SVC_STATE_RESET)
1253 			ret = -EINVAL;
1254 		break;
1255 	case GB_SVC_TYPE_SVC_HELLO:
1256 		if (svc->state != GB_SVC_STATE_PROTOCOL_VERSION)
1257 			ret = -EINVAL;
1258 		break;
1259 	default:
1260 		if (svc->state != GB_SVC_STATE_SVC_HELLO)
1261 			ret = -EINVAL;
1262 		break;
1263 	}
1264 
1265 	if (ret) {
1266 		dev_warn(&svc->dev, "unexpected request 0x%02x received (state %u)\n",
1267 			 type, svc->state);
1268 		return ret;
1269 	}
1270 
1271 	switch (type) {
1272 	case GB_SVC_TYPE_PROTOCOL_VERSION:
1273 		ret = gb_svc_version_request(op);
1274 		if (!ret)
1275 			svc->state = GB_SVC_STATE_PROTOCOL_VERSION;
1276 		return ret;
1277 	case GB_SVC_TYPE_SVC_HELLO:
1278 		ret = gb_svc_hello(op);
1279 		if (!ret)
1280 			svc->state = GB_SVC_STATE_SVC_HELLO;
1281 		return ret;
1282 	case GB_SVC_TYPE_INTF_RESET:
1283 		return gb_svc_intf_reset_recv(op);
1284 	case GB_SVC_TYPE_MODULE_INSERTED:
1285 		return gb_svc_module_inserted_recv(op);
1286 	case GB_SVC_TYPE_MODULE_REMOVED:
1287 		return gb_svc_module_removed_recv(op);
1288 	case GB_SVC_TYPE_INTF_MAILBOX_EVENT:
1289 		return gb_svc_intf_mailbox_event_recv(op);
1290 	case GB_SVC_TYPE_INTF_OOPS:
1291 		return gb_svc_intf_oops_recv(op);
1292 	default:
1293 		dev_warn(&svc->dev, "unsupported request 0x%02x\n", type);
1294 		return -EINVAL;
1295 	}
1296 }
1297 
1298 static void gb_svc_release(struct device *dev)
1299 {
1300 	struct gb_svc *svc = to_gb_svc(dev);
1301 
1302 	if (svc->connection)
1303 		gb_connection_destroy(svc->connection);
1304 	ida_destroy(&svc->device_id_map);
1305 	destroy_workqueue(svc->wq);
1306 	kfree(svc);
1307 }
1308 
1309 const struct device_type greybus_svc_type = {
1310 	.name		= "greybus_svc",
1311 	.release	= gb_svc_release,
1312 };
1313 
1314 struct gb_svc *gb_svc_create(struct gb_host_device *hd)
1315 {
1316 	struct gb_svc *svc;
1317 
1318 	svc = kzalloc(sizeof(*svc), GFP_KERNEL);
1319 	if (!svc)
1320 		return NULL;
1321 
1322 	svc->wq = alloc_ordered_workqueue("%s:svc", 0, dev_name(&hd->dev));
1323 	if (!svc->wq) {
1324 		kfree(svc);
1325 		return NULL;
1326 	}
1327 
1328 	svc->dev.parent = &hd->dev;
1329 	svc->dev.bus = &greybus_bus_type;
1330 	svc->dev.type = &greybus_svc_type;
1331 	svc->dev.groups = svc_groups;
1332 	svc->dev.dma_mask = svc->dev.parent->dma_mask;
1333 	device_initialize(&svc->dev);
1334 
1335 	dev_set_name(&svc->dev, "%d-svc", hd->bus_id);
1336 
1337 	ida_init(&svc->device_id_map);
1338 	svc->state = GB_SVC_STATE_RESET;
1339 	svc->hd = hd;
1340 
1341 	svc->connection = gb_connection_create_static(hd, GB_SVC_CPORT_ID,
1342 						      gb_svc_request_handler);
1343 	if (IS_ERR(svc->connection)) {
1344 		dev_err(&svc->dev, "failed to create connection: %ld\n",
1345 			PTR_ERR(svc->connection));
1346 		goto err_put_device;
1347 	}
1348 
1349 	gb_connection_set_data(svc->connection, svc);
1350 
1351 	return svc;
1352 
1353 err_put_device:
1354 	put_device(&svc->dev);
1355 	return NULL;
1356 }
1357 
1358 int gb_svc_add(struct gb_svc *svc)
1359 {
1360 	int ret;
1361 
1362 	/*
1363 	 * The SVC protocol is currently driven by the SVC, so the SVC device
1364 	 * is added from the connection request handler when enough
1365 	 * information has been received.
1366 	 */
1367 	ret = gb_connection_enable(svc->connection);
1368 	if (ret)
1369 		return ret;
1370 
1371 	return 0;
1372 }
1373 
1374 static void gb_svc_remove_modules(struct gb_svc *svc)
1375 {
1376 	struct gb_host_device *hd = svc->hd;
1377 	struct gb_module *module, *tmp;
1378 
1379 	list_for_each_entry_safe(module, tmp, &hd->modules, hd_node) {
1380 		gb_module_del(module);
1381 		list_del(&module->hd_node);
1382 		gb_module_put(module);
1383 	}
1384 }
1385 
1386 void gb_svc_del(struct gb_svc *svc)
1387 {
1388 	gb_connection_disable_rx(svc->connection);
1389 
1390 	/*
1391 	 * The SVC device may have been registered from the request handler.
1392 	 */
1393 	if (device_is_registered(&svc->dev)) {
1394 		gb_svc_debugfs_exit(svc);
1395 		gb_svc_watchdog_destroy(svc);
1396 		device_del(&svc->dev);
1397 	}
1398 
1399 	flush_workqueue(svc->wq);
1400 
1401 	gb_svc_remove_modules(svc);
1402 
1403 	gb_connection_disable(svc->connection);
1404 }
1405 
1406 void gb_svc_put(struct gb_svc *svc)
1407 {
1408 	put_device(&svc->dev);
1409 }
1410