xref: /openbmc/linux/drivers/misc/mei/hbm.c (revision fb574682)
1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  * Copyright (c) 2003-2019, Intel Corporation. All rights reserved.
4  * Intel Management Engine Interface (Intel MEI) Linux driver
5  */
6 #include <linux/export.h>
7 #include <linux/sched.h>
8 #include <linux/wait.h>
9 #include <linux/pm_runtime.h>
10 #include <linux/slab.h>
11 
12 #include <linux/mei.h>
13 
14 #include "mei_dev.h"
15 #include "hbm.h"
16 #include "client.h"
17 
18 static const char *mei_hbm_status_str(enum mei_hbm_status status)
19 {
20 #define MEI_HBM_STATUS(status) case MEI_HBMS_##status: return #status
21 	switch (status) {
22 	MEI_HBM_STATUS(SUCCESS);
23 	MEI_HBM_STATUS(CLIENT_NOT_FOUND);
24 	MEI_HBM_STATUS(ALREADY_EXISTS);
25 	MEI_HBM_STATUS(REJECTED);
26 	MEI_HBM_STATUS(INVALID_PARAMETER);
27 	MEI_HBM_STATUS(NOT_ALLOWED);
28 	MEI_HBM_STATUS(ALREADY_STARTED);
29 	MEI_HBM_STATUS(NOT_STARTED);
30 	default: return "unknown";
31 	}
32 #undef MEI_HBM_STATUS
33 };
34 
35 static const char *mei_cl_conn_status_str(enum mei_cl_connect_status status)
36 {
37 #define MEI_CL_CS(status) case MEI_CL_CONN_##status: return #status
38 	switch (status) {
39 	MEI_CL_CS(SUCCESS);
40 	MEI_CL_CS(NOT_FOUND);
41 	MEI_CL_CS(ALREADY_STARTED);
42 	MEI_CL_CS(OUT_OF_RESOURCES);
43 	MEI_CL_CS(MESSAGE_SMALL);
44 	MEI_CL_CS(NOT_ALLOWED);
45 	default: return "unknown";
46 	}
47 #undef MEI_CL_CCS
48 }
49 
50 const char *mei_hbm_state_str(enum mei_hbm_state state)
51 {
52 #define MEI_HBM_STATE(state) case MEI_HBM_##state: return #state
53 	switch (state) {
54 	MEI_HBM_STATE(IDLE);
55 	MEI_HBM_STATE(STARTING);
56 	MEI_HBM_STATE(STARTED);
57 	MEI_HBM_STATE(DR_SETUP);
58 	MEI_HBM_STATE(ENUM_CLIENTS);
59 	MEI_HBM_STATE(CLIENT_PROPERTIES);
60 	MEI_HBM_STATE(STOPPED);
61 	default:
62 		return "unknown";
63 	}
64 #undef MEI_HBM_STATE
65 }
66 
67 /**
68  * mei_cl_conn_status_to_errno - convert client connect response
69  * status to error code
70  *
71  * @status: client connect response status
72  *
73  * Return: corresponding error code
74  */
75 static int mei_cl_conn_status_to_errno(enum mei_cl_connect_status status)
76 {
77 	switch (status) {
78 	case MEI_CL_CONN_SUCCESS:          return 0;
79 	case MEI_CL_CONN_NOT_FOUND:        return -ENOTTY;
80 	case MEI_CL_CONN_ALREADY_STARTED:  return -EBUSY;
81 	case MEI_CL_CONN_OUT_OF_RESOURCES: return -EBUSY;
82 	case MEI_CL_CONN_MESSAGE_SMALL:    return -EINVAL;
83 	case MEI_CL_CONN_NOT_ALLOWED:      return -EBUSY;
84 	default:                           return -EINVAL;
85 	}
86 }
87 
88 /**
89  * mei_hbm_write_message - wrapper for sending hbm messages.
90  *
91  * @dev: mei device
92  * @hdr: mei header
93  * @data: payload
94  */
95 static inline int mei_hbm_write_message(struct mei_device *dev,
96 					struct mei_msg_hdr *hdr,
97 					const void *data)
98 {
99 	return mei_write_message(dev, hdr, sizeof(*hdr), data, hdr->length);
100 }
101 
102 /**
103  * mei_hbm_idle - set hbm to idle state
104  *
105  * @dev: the device structure
106  */
107 void mei_hbm_idle(struct mei_device *dev)
108 {
109 	dev->init_clients_timer = 0;
110 	dev->hbm_state = MEI_HBM_IDLE;
111 }
112 
113 /**
114  * mei_hbm_reset - reset hbm counters and book keeping data structurs
115  *
116  * @dev: the device structure
117  */
118 void mei_hbm_reset(struct mei_device *dev)
119 {
120 	mei_me_cl_rm_all(dev);
121 
122 	mei_hbm_idle(dev);
123 }
124 
125 /**
126  * mei_hbm_hdr - construct hbm header
127  *
128  * @hdr: hbm header
129  * @length: payload length
130  */
131 
132 static inline void mei_hbm_hdr(struct mei_msg_hdr *hdr, size_t length)
133 {
134 	hdr->host_addr = 0;
135 	hdr->me_addr = 0;
136 	hdr->length = length;
137 	hdr->msg_complete = 1;
138 	hdr->dma_ring = 0;
139 	hdr->reserved = 0;
140 	hdr->internal = 0;
141 }
142 
143 /**
144  * mei_hbm_cl_hdr - construct client hbm header
145  *
146  * @cl: client
147  * @hbm_cmd: host bus message command
148  * @buf: buffer for cl header
149  * @len: buffer length
150  */
151 static inline
152 void mei_hbm_cl_hdr(struct mei_cl *cl, u8 hbm_cmd, void *buf, size_t len)
153 {
154 	struct mei_hbm_cl_cmd *cmd = buf;
155 
156 	memset(cmd, 0, len);
157 
158 	cmd->hbm_cmd = hbm_cmd;
159 	cmd->host_addr = mei_cl_host_addr(cl);
160 	cmd->me_addr = mei_cl_me_id(cl);
161 }
162 
163 /**
164  * mei_hbm_cl_write - write simple hbm client message
165  *
166  * @dev: the device structure
167  * @cl: client
168  * @hbm_cmd: host bus message command
169  * @buf: message buffer
170  * @len: buffer length
171  *
172  * Return: 0 on success, <0 on failure.
173  */
174 static inline int mei_hbm_cl_write(struct mei_device *dev, struct mei_cl *cl,
175 				   u8 hbm_cmd, void *buf, size_t len)
176 {
177 	struct mei_msg_hdr mei_hdr;
178 
179 	mei_hbm_hdr(&mei_hdr, len);
180 	mei_hbm_cl_hdr(cl, hbm_cmd, buf, len);
181 
182 	return mei_hbm_write_message(dev, &mei_hdr, buf);
183 }
184 
185 /**
186  * mei_hbm_cl_addr_equal - check if the client's and
187  *	the message address match
188  *
189  * @cl: client
190  * @cmd: hbm client message
191  *
192  * Return: true if addresses are the same
193  */
194 static inline
195 bool mei_hbm_cl_addr_equal(struct mei_cl *cl, struct mei_hbm_cl_cmd *cmd)
196 {
197 	return  mei_cl_host_addr(cl) == cmd->host_addr &&
198 		mei_cl_me_id(cl) == cmd->me_addr;
199 }
200 
201 /**
202  * mei_hbm_cl_find_by_cmd - find recipient client
203  *
204  * @dev: the device structure
205  * @buf: a buffer with hbm cl command
206  *
207  * Return: the recipient client or NULL if not found
208  */
209 static inline
210 struct mei_cl *mei_hbm_cl_find_by_cmd(struct mei_device *dev, void *buf)
211 {
212 	struct mei_hbm_cl_cmd *cmd = (struct mei_hbm_cl_cmd *)buf;
213 	struct mei_cl *cl;
214 
215 	list_for_each_entry(cl, &dev->file_list, link)
216 		if (mei_hbm_cl_addr_equal(cl, cmd))
217 			return cl;
218 	return NULL;
219 }
220 
221 
222 /**
223  * mei_hbm_start_wait - wait for start response message.
224  *
225  * @dev: the device structure
226  *
227  * Return: 0 on success and < 0 on failure
228  */
229 int mei_hbm_start_wait(struct mei_device *dev)
230 {
231 	int ret;
232 
233 	if (dev->hbm_state > MEI_HBM_STARTING)
234 		return 0;
235 
236 	mutex_unlock(&dev->device_lock);
237 	ret = wait_event_timeout(dev->wait_hbm_start,
238 			dev->hbm_state != MEI_HBM_STARTING,
239 			mei_secs_to_jiffies(MEI_HBM_TIMEOUT));
240 	mutex_lock(&dev->device_lock);
241 
242 	if (ret == 0 && (dev->hbm_state <= MEI_HBM_STARTING)) {
243 		dev->hbm_state = MEI_HBM_IDLE;
244 		dev_err(dev->dev, "waiting for mei start failed\n");
245 		return -ETIME;
246 	}
247 	return 0;
248 }
249 
250 /**
251  * mei_hbm_start_req - sends start request message.
252  *
253  * @dev: the device structure
254  *
255  * Return: 0 on success and < 0 on failure
256  */
257 int mei_hbm_start_req(struct mei_device *dev)
258 {
259 	struct mei_msg_hdr mei_hdr;
260 	struct hbm_host_version_request start_req;
261 	const size_t len = sizeof(struct hbm_host_version_request);
262 	int ret;
263 
264 	mei_hbm_reset(dev);
265 
266 	mei_hbm_hdr(&mei_hdr, len);
267 
268 	/* host start message */
269 	memset(&start_req, 0, len);
270 	start_req.hbm_cmd = HOST_START_REQ_CMD;
271 	start_req.host_version.major_version = HBM_MAJOR_VERSION;
272 	start_req.host_version.minor_version = HBM_MINOR_VERSION;
273 
274 	dev->hbm_state = MEI_HBM_IDLE;
275 	ret = mei_hbm_write_message(dev, &mei_hdr, &start_req);
276 	if (ret) {
277 		dev_err(dev->dev, "version message write failed: ret = %d\n",
278 			ret);
279 		return ret;
280 	}
281 
282 	dev->hbm_state = MEI_HBM_STARTING;
283 	dev->init_clients_timer = MEI_CLIENTS_INIT_TIMEOUT;
284 	mei_schedule_stall_timer(dev);
285 	return 0;
286 }
287 
288 /**
289  * mei_hbm_dma_setup_req() - setup DMA request
290  * @dev: the device structure
291  *
292  * Return: 0 on success and < 0 on failure
293  */
294 static int mei_hbm_dma_setup_req(struct mei_device *dev)
295 {
296 	struct mei_msg_hdr mei_hdr;
297 	struct hbm_dma_setup_request req;
298 	const size_t len = sizeof(struct hbm_dma_setup_request);
299 	unsigned int i;
300 	int ret;
301 
302 	mei_hbm_hdr(&mei_hdr, len);
303 
304 	memset(&req, 0, len);
305 	req.hbm_cmd = MEI_HBM_DMA_SETUP_REQ_CMD;
306 	for (i = 0; i < DMA_DSCR_NUM; i++) {
307 		phys_addr_t paddr;
308 
309 		paddr = dev->dr_dscr[i].daddr;
310 		req.dma_dscr[i].addr_hi = upper_32_bits(paddr);
311 		req.dma_dscr[i].addr_lo = lower_32_bits(paddr);
312 		req.dma_dscr[i].size = dev->dr_dscr[i].size;
313 	}
314 
315 	mei_dma_ring_reset(dev);
316 
317 	ret = mei_hbm_write_message(dev, &mei_hdr, &req);
318 	if (ret) {
319 		dev_err(dev->dev, "dma setup request write failed: ret = %d.\n",
320 			ret);
321 		return ret;
322 	}
323 
324 	dev->hbm_state = MEI_HBM_DR_SETUP;
325 	dev->init_clients_timer = MEI_CLIENTS_INIT_TIMEOUT;
326 	mei_schedule_stall_timer(dev);
327 	return 0;
328 }
329 
330 /**
331  * mei_hbm_enum_clients_req - sends enumeration client request message.
332  *
333  * @dev: the device structure
334  *
335  * Return: 0 on success and < 0 on failure
336  */
337 static int mei_hbm_enum_clients_req(struct mei_device *dev)
338 {
339 	struct mei_msg_hdr mei_hdr;
340 	struct hbm_host_enum_request enum_req;
341 	const size_t len = sizeof(struct hbm_host_enum_request);
342 	int ret;
343 
344 	/* enumerate clients */
345 	mei_hbm_hdr(&mei_hdr, len);
346 
347 	memset(&enum_req, 0, len);
348 	enum_req.hbm_cmd = HOST_ENUM_REQ_CMD;
349 	enum_req.flags |= dev->hbm_f_dc_supported ?
350 			  MEI_HBM_ENUM_F_ALLOW_ADD : 0;
351 	enum_req.flags |= dev->hbm_f_ie_supported ?
352 			  MEI_HBM_ENUM_F_IMMEDIATE_ENUM : 0;
353 
354 	ret = mei_hbm_write_message(dev, &mei_hdr, &enum_req);
355 	if (ret) {
356 		dev_err(dev->dev, "enumeration request write failed: ret = %d.\n",
357 			ret);
358 		return ret;
359 	}
360 	dev->hbm_state = MEI_HBM_ENUM_CLIENTS;
361 	dev->init_clients_timer = MEI_CLIENTS_INIT_TIMEOUT;
362 	mei_schedule_stall_timer(dev);
363 	return 0;
364 }
365 
366 /**
367  * mei_hbm_me_cl_add - add new me client to the list
368  *
369  * @dev: the device structure
370  * @res: hbm property response
371  *
372  * Return: 0 on success and -ENOMEM on allocation failure
373  */
374 
375 static int mei_hbm_me_cl_add(struct mei_device *dev,
376 			     struct hbm_props_response *res)
377 {
378 	struct mei_me_client *me_cl;
379 	const uuid_le *uuid = &res->client_properties.protocol_name;
380 
381 	mei_me_cl_rm_by_uuid(dev, uuid);
382 
383 	me_cl = kzalloc(sizeof(struct mei_me_client), GFP_KERNEL);
384 	if (!me_cl)
385 		return -ENOMEM;
386 
387 	mei_me_cl_init(me_cl);
388 
389 	me_cl->props = res->client_properties;
390 	me_cl->client_id = res->me_addr;
391 	me_cl->tx_flow_ctrl_creds = 0;
392 
393 	mei_me_cl_add(dev, me_cl);
394 
395 	return 0;
396 }
397 
398 /**
399  * mei_hbm_add_cl_resp - send response to fw on client add request
400  *
401  * @dev: the device structure
402  * @addr: me address
403  * @status: response status
404  *
405  * Return: 0 on success and < 0 on failure
406  */
407 static int mei_hbm_add_cl_resp(struct mei_device *dev, u8 addr, u8 status)
408 {
409 	struct mei_msg_hdr mei_hdr;
410 	struct hbm_add_client_response resp;
411 	const size_t len = sizeof(struct hbm_add_client_response);
412 	int ret;
413 
414 	dev_dbg(dev->dev, "adding client response\n");
415 
416 	mei_hbm_hdr(&mei_hdr, len);
417 
418 	memset(&resp, 0, sizeof(struct hbm_add_client_response));
419 	resp.hbm_cmd = MEI_HBM_ADD_CLIENT_RES_CMD;
420 	resp.me_addr = addr;
421 	resp.status  = status;
422 
423 	ret = mei_hbm_write_message(dev, &mei_hdr, &resp);
424 	if (ret)
425 		dev_err(dev->dev, "add client response write failed: ret = %d\n",
426 			ret);
427 	return ret;
428 }
429 
430 /**
431  * mei_hbm_fw_add_cl_req - request from the fw to add a client
432  *
433  * @dev: the device structure
434  * @req: add client request
435  *
436  * Return: 0 on success and < 0 on failure
437  */
438 static int mei_hbm_fw_add_cl_req(struct mei_device *dev,
439 			      struct hbm_add_client_request *req)
440 {
441 	int ret;
442 	u8 status = MEI_HBMS_SUCCESS;
443 
444 	BUILD_BUG_ON(sizeof(struct hbm_add_client_request) !=
445 			sizeof(struct hbm_props_response));
446 
447 	ret = mei_hbm_me_cl_add(dev, (struct hbm_props_response *)req);
448 	if (ret)
449 		status = !MEI_HBMS_SUCCESS;
450 
451 	if (dev->dev_state == MEI_DEV_ENABLED)
452 		schedule_work(&dev->bus_rescan_work);
453 
454 	return mei_hbm_add_cl_resp(dev, req->me_addr, status);
455 }
456 
457 /**
458  * mei_hbm_cl_notify_req - send notification request
459  *
460  * @dev: the device structure
461  * @cl: a client to disconnect from
462  * @start: true for start false for stop
463  *
464  * Return: 0 on success and -EIO on write failure
465  */
466 int mei_hbm_cl_notify_req(struct mei_device *dev,
467 			  struct mei_cl *cl, u8 start)
468 {
469 
470 	struct mei_msg_hdr mei_hdr;
471 	struct hbm_notification_request req;
472 	const size_t len = sizeof(struct hbm_notification_request);
473 	int ret;
474 
475 	mei_hbm_hdr(&mei_hdr, len);
476 	mei_hbm_cl_hdr(cl, MEI_HBM_NOTIFY_REQ_CMD, &req, len);
477 
478 	req.start = start;
479 
480 	ret = mei_hbm_write_message(dev, &mei_hdr, &req);
481 	if (ret)
482 		dev_err(dev->dev, "notify request failed: ret = %d\n", ret);
483 
484 	return ret;
485 }
486 
487 /**
488  *  notify_res_to_fop - convert notification response to the proper
489  *      notification FOP
490  *
491  * @cmd: client notification start response command
492  *
493  * Return:  MEI_FOP_NOTIFY_START or MEI_FOP_NOTIFY_STOP;
494  */
495 static inline enum mei_cb_file_ops notify_res_to_fop(struct mei_hbm_cl_cmd *cmd)
496 {
497 	struct hbm_notification_response *rs =
498 		(struct hbm_notification_response *)cmd;
499 
500 	return mei_cl_notify_req2fop(rs->start);
501 }
502 
503 /**
504  * mei_hbm_cl_notify_start_res - update the client state according
505  *       notify start response
506  *
507  * @dev: the device structure
508  * @cl: mei host client
509  * @cmd: client notification start response command
510  */
511 static void mei_hbm_cl_notify_start_res(struct mei_device *dev,
512 					struct mei_cl *cl,
513 					struct mei_hbm_cl_cmd *cmd)
514 {
515 	struct hbm_notification_response *rs =
516 		(struct hbm_notification_response *)cmd;
517 
518 	cl_dbg(dev, cl, "hbm: notify start response status=%d\n", rs->status);
519 
520 	if (rs->status == MEI_HBMS_SUCCESS ||
521 	    rs->status == MEI_HBMS_ALREADY_STARTED) {
522 		cl->notify_en = true;
523 		cl->status = 0;
524 	} else {
525 		cl->status = -EINVAL;
526 	}
527 }
528 
529 /**
530  * mei_hbm_cl_notify_stop_res - update the client state according
531  *       notify stop response
532  *
533  * @dev: the device structure
534  * @cl: mei host client
535  * @cmd: client notification stop response command
536  */
537 static void mei_hbm_cl_notify_stop_res(struct mei_device *dev,
538 				       struct mei_cl *cl,
539 				       struct mei_hbm_cl_cmd *cmd)
540 {
541 	struct hbm_notification_response *rs =
542 		(struct hbm_notification_response *)cmd;
543 
544 	cl_dbg(dev, cl, "hbm: notify stop response status=%d\n", rs->status);
545 
546 	if (rs->status == MEI_HBMS_SUCCESS ||
547 	    rs->status == MEI_HBMS_NOT_STARTED) {
548 		cl->notify_en = false;
549 		cl->status = 0;
550 	} else {
551 		/* TODO: spec is not clear yet about other possible issues */
552 		cl->status = -EINVAL;
553 	}
554 }
555 
556 /**
557  * mei_hbm_cl_notify - signal notification event
558  *
559  * @dev: the device structure
560  * @cmd: notification client message
561  */
562 static void mei_hbm_cl_notify(struct mei_device *dev,
563 			      struct mei_hbm_cl_cmd *cmd)
564 {
565 	struct mei_cl *cl;
566 
567 	cl = mei_hbm_cl_find_by_cmd(dev, cmd);
568 	if (cl)
569 		mei_cl_notify(cl);
570 }
571 
572 /**
573  * mei_hbm_prop_req - request property for a single client
574  *
575  * @dev: the device structure
576  * @start_idx: client index to start search
577  *
578  * Return: 0 on success and < 0 on failure
579  */
580 static int mei_hbm_prop_req(struct mei_device *dev, unsigned long start_idx)
581 {
582 	struct mei_msg_hdr mei_hdr;
583 	struct hbm_props_request prop_req;
584 	const size_t len = sizeof(struct hbm_props_request);
585 	unsigned long addr;
586 	int ret;
587 
588 	addr = find_next_bit(dev->me_clients_map, MEI_CLIENTS_MAX, start_idx);
589 
590 	/* We got all client properties */
591 	if (addr == MEI_CLIENTS_MAX) {
592 		dev->hbm_state = MEI_HBM_STARTED;
593 		mei_host_client_init(dev);
594 
595 		return 0;
596 	}
597 
598 	mei_hbm_hdr(&mei_hdr, len);
599 
600 	memset(&prop_req, 0, sizeof(struct hbm_props_request));
601 
602 	prop_req.hbm_cmd = HOST_CLIENT_PROPERTIES_REQ_CMD;
603 	prop_req.me_addr = addr;
604 
605 	ret = mei_hbm_write_message(dev, &mei_hdr, &prop_req);
606 	if (ret) {
607 		dev_err(dev->dev, "properties request write failed: ret = %d\n",
608 			ret);
609 		return ret;
610 	}
611 
612 	dev->init_clients_timer = MEI_CLIENTS_INIT_TIMEOUT;
613 	mei_schedule_stall_timer(dev);
614 
615 	return 0;
616 }
617 
618 /**
619  * mei_hbm_pg - sends pg command
620  *
621  * @dev: the device structure
622  * @pg_cmd: the pg command code
623  *
624  * Return: -EIO on write failure
625  *         -EOPNOTSUPP if the operation is not supported by the protocol
626  */
627 int mei_hbm_pg(struct mei_device *dev, u8 pg_cmd)
628 {
629 	struct mei_msg_hdr mei_hdr;
630 	struct hbm_power_gate req;
631 	const size_t len = sizeof(struct hbm_power_gate);
632 	int ret;
633 
634 	if (!dev->hbm_f_pg_supported)
635 		return -EOPNOTSUPP;
636 
637 	mei_hbm_hdr(&mei_hdr, len);
638 
639 	memset(&req, 0, len);
640 	req.hbm_cmd = pg_cmd;
641 
642 	ret = mei_hbm_write_message(dev, &mei_hdr, &req);
643 	if (ret)
644 		dev_err(dev->dev, "power gate command write failed.\n");
645 	return ret;
646 }
647 EXPORT_SYMBOL_GPL(mei_hbm_pg);
648 
649 /**
650  * mei_hbm_stop_req - send stop request message
651  *
652  * @dev: mei device
653  *
654  * Return: -EIO on write failure
655  */
656 static int mei_hbm_stop_req(struct mei_device *dev)
657 {
658 	struct mei_msg_hdr mei_hdr;
659 	struct hbm_host_stop_request req;
660 	const size_t len = sizeof(struct hbm_host_stop_request);
661 
662 	mei_hbm_hdr(&mei_hdr, len);
663 
664 	memset(&req, 0, len);
665 	req.hbm_cmd = HOST_STOP_REQ_CMD;
666 	req.reason = DRIVER_STOP_REQUEST;
667 
668 	return mei_hbm_write_message(dev, &mei_hdr, &req);
669 }
670 
671 /**
672  * mei_hbm_cl_flow_control_req - sends flow control request.
673  *
674  * @dev: the device structure
675  * @cl: client info
676  *
677  * Return: -EIO on write failure
678  */
679 int mei_hbm_cl_flow_control_req(struct mei_device *dev, struct mei_cl *cl)
680 {
681 	struct hbm_flow_control req;
682 
683 	cl_dbg(dev, cl, "sending flow control\n");
684 	return mei_hbm_cl_write(dev, cl, MEI_FLOW_CONTROL_CMD,
685 				&req, sizeof(req));
686 }
687 
688 /**
689  * mei_hbm_add_single_tx_flow_ctrl_creds - adds single buffer credentials.
690  *
691  * @dev: the device structure
692  * @fctrl: flow control response bus message
693  *
694  * Return: 0 on success, < 0 otherwise
695  */
696 static int mei_hbm_add_single_tx_flow_ctrl_creds(struct mei_device *dev,
697 						 struct hbm_flow_control *fctrl)
698 {
699 	struct mei_me_client *me_cl;
700 	int rets;
701 
702 	me_cl = mei_me_cl_by_id(dev, fctrl->me_addr);
703 	if (!me_cl) {
704 		dev_err(dev->dev, "no such me client %d\n", fctrl->me_addr);
705 		return -ENOENT;
706 	}
707 
708 	if (WARN_ON(me_cl->props.single_recv_buf == 0)) {
709 		rets = -EINVAL;
710 		goto out;
711 	}
712 
713 	me_cl->tx_flow_ctrl_creds++;
714 	dev_dbg(dev->dev, "recv flow ctrl msg ME %d (single) creds = %d.\n",
715 		fctrl->me_addr, me_cl->tx_flow_ctrl_creds);
716 
717 	rets = 0;
718 out:
719 	mei_me_cl_put(me_cl);
720 	return rets;
721 }
722 
723 /**
724  * mei_hbm_cl_flow_control_res - flow control response from me
725  *
726  * @dev: the device structure
727  * @fctrl: flow control response bus message
728  */
729 static void mei_hbm_cl_tx_flow_ctrl_creds_res(struct mei_device *dev,
730 					       struct hbm_flow_control *fctrl)
731 {
732 	struct mei_cl *cl;
733 
734 	if (!fctrl->host_addr) {
735 		/* single receive buffer */
736 		mei_hbm_add_single_tx_flow_ctrl_creds(dev, fctrl);
737 		return;
738 	}
739 
740 	cl = mei_hbm_cl_find_by_cmd(dev, fctrl);
741 	if (cl) {
742 		cl->tx_flow_ctrl_creds++;
743 		cl_dbg(dev, cl, "flow control creds = %d.\n",
744 				cl->tx_flow_ctrl_creds);
745 	}
746 }
747 
748 
749 /**
750  * mei_hbm_cl_disconnect_req - sends disconnect message to fw.
751  *
752  * @dev: the device structure
753  * @cl: a client to disconnect from
754  *
755  * Return: -EIO on write failure
756  */
757 int mei_hbm_cl_disconnect_req(struct mei_device *dev, struct mei_cl *cl)
758 {
759 	struct hbm_client_connect_request req;
760 
761 	return mei_hbm_cl_write(dev, cl, CLIENT_DISCONNECT_REQ_CMD,
762 				&req, sizeof(req));
763 }
764 
765 /**
766  * mei_hbm_cl_disconnect_rsp - sends disconnect respose to the FW
767  *
768  * @dev: the device structure
769  * @cl: a client to disconnect from
770  *
771  * Return: -EIO on write failure
772  */
773 int mei_hbm_cl_disconnect_rsp(struct mei_device *dev, struct mei_cl *cl)
774 {
775 	struct hbm_client_connect_response resp;
776 
777 	return mei_hbm_cl_write(dev, cl, CLIENT_DISCONNECT_RES_CMD,
778 				&resp, sizeof(resp));
779 }
780 
781 /**
782  * mei_hbm_cl_disconnect_res - update the client state according
783  *       disconnect response
784  *
785  * @dev: the device structure
786  * @cl: mei host client
787  * @cmd: disconnect client response host bus message
788  */
789 static void mei_hbm_cl_disconnect_res(struct mei_device *dev, struct mei_cl *cl,
790 				      struct mei_hbm_cl_cmd *cmd)
791 {
792 	struct hbm_client_connect_response *rs =
793 		(struct hbm_client_connect_response *)cmd;
794 
795 	cl_dbg(dev, cl, "hbm: disconnect response status=%d\n", rs->status);
796 
797 	if (rs->status == MEI_CL_DISCONN_SUCCESS)
798 		cl->state = MEI_FILE_DISCONNECT_REPLY;
799 	cl->status = 0;
800 }
801 
802 /**
803  * mei_hbm_cl_connect_req - send connection request to specific me client
804  *
805  * @dev: the device structure
806  * @cl: a client to connect to
807  *
808  * Return: -EIO on write failure
809  */
810 int mei_hbm_cl_connect_req(struct mei_device *dev, struct mei_cl *cl)
811 {
812 	struct hbm_client_connect_request req;
813 
814 	return mei_hbm_cl_write(dev, cl, CLIENT_CONNECT_REQ_CMD,
815 				&req, sizeof(req));
816 }
817 
818 /**
819  * mei_hbm_cl_connect_res - update the client state according
820  *        connection response
821  *
822  * @dev: the device structure
823  * @cl: mei host client
824  * @cmd: connect client response host bus message
825  */
826 static void mei_hbm_cl_connect_res(struct mei_device *dev, struct mei_cl *cl,
827 				   struct mei_hbm_cl_cmd *cmd)
828 {
829 	struct hbm_client_connect_response *rs =
830 		(struct hbm_client_connect_response *)cmd;
831 
832 	cl_dbg(dev, cl, "hbm: connect response status=%s\n",
833 			mei_cl_conn_status_str(rs->status));
834 
835 	if (rs->status == MEI_CL_CONN_SUCCESS)
836 		cl->state = MEI_FILE_CONNECTED;
837 	else {
838 		cl->state = MEI_FILE_DISCONNECT_REPLY;
839 		if (rs->status == MEI_CL_CONN_NOT_FOUND) {
840 			mei_me_cl_del(dev, cl->me_cl);
841 			if (dev->dev_state == MEI_DEV_ENABLED)
842 				schedule_work(&dev->bus_rescan_work);
843 		}
844 	}
845 	cl->status = mei_cl_conn_status_to_errno(rs->status);
846 }
847 
848 /**
849  * mei_hbm_cl_res - process hbm response received on behalf
850  *         an client
851  *
852  * @dev: the device structure
853  * @rs:  hbm client message
854  * @fop_type: file operation type
855  */
856 static void mei_hbm_cl_res(struct mei_device *dev,
857 			   struct mei_hbm_cl_cmd *rs,
858 			   enum mei_cb_file_ops fop_type)
859 {
860 	struct mei_cl *cl;
861 	struct mei_cl_cb *cb, *next;
862 
863 	cl = NULL;
864 	list_for_each_entry_safe(cb, next, &dev->ctrl_rd_list, list) {
865 
866 		cl = cb->cl;
867 
868 		if (cb->fop_type != fop_type)
869 			continue;
870 
871 		if (mei_hbm_cl_addr_equal(cl, rs)) {
872 			list_del_init(&cb->list);
873 			break;
874 		}
875 	}
876 
877 	if (!cl)
878 		return;
879 
880 	switch (fop_type) {
881 	case MEI_FOP_CONNECT:
882 		mei_hbm_cl_connect_res(dev, cl, rs);
883 		break;
884 	case MEI_FOP_DISCONNECT:
885 		mei_hbm_cl_disconnect_res(dev, cl, rs);
886 		break;
887 	case MEI_FOP_NOTIFY_START:
888 		mei_hbm_cl_notify_start_res(dev, cl, rs);
889 		break;
890 	case MEI_FOP_NOTIFY_STOP:
891 		mei_hbm_cl_notify_stop_res(dev, cl, rs);
892 		break;
893 	default:
894 		return;
895 	}
896 
897 	cl->timer_count = 0;
898 	wake_up(&cl->wait);
899 }
900 
901 
902 /**
903  * mei_hbm_fw_disconnect_req - disconnect request initiated by ME firmware
904  *  host sends disconnect response
905  *
906  * @dev: the device structure.
907  * @disconnect_req: disconnect request bus message from the me
908  *
909  * Return: -ENOMEM on allocation failure
910  */
911 static int mei_hbm_fw_disconnect_req(struct mei_device *dev,
912 		struct hbm_client_connect_request *disconnect_req)
913 {
914 	struct mei_cl *cl;
915 	struct mei_cl_cb *cb;
916 
917 	cl = mei_hbm_cl_find_by_cmd(dev, disconnect_req);
918 	if (cl) {
919 		cl_warn(dev, cl, "fw disconnect request received\n");
920 		cl->state = MEI_FILE_DISCONNECTING;
921 		cl->timer_count = 0;
922 
923 		cb = mei_cl_enqueue_ctrl_wr_cb(cl, 0, MEI_FOP_DISCONNECT_RSP,
924 					       NULL);
925 		if (!cb)
926 			return -ENOMEM;
927 	}
928 	return 0;
929 }
930 
931 /**
932  * mei_hbm_pg_enter_res - PG enter response received
933  *
934  * @dev: the device structure.
935  *
936  * Return: 0 on success, -EPROTO on state mismatch
937  */
938 static int mei_hbm_pg_enter_res(struct mei_device *dev)
939 {
940 	if (mei_pg_state(dev) != MEI_PG_OFF ||
941 	    dev->pg_event != MEI_PG_EVENT_WAIT) {
942 		dev_err(dev->dev, "hbm: pg entry response: state mismatch [%s, %d]\n",
943 			mei_pg_state_str(mei_pg_state(dev)), dev->pg_event);
944 		return -EPROTO;
945 	}
946 
947 	dev->pg_event = MEI_PG_EVENT_RECEIVED;
948 	wake_up(&dev->wait_pg);
949 
950 	return 0;
951 }
952 
953 /**
954  * mei_hbm_pg_resume - process with PG resume
955  *
956  * @dev: the device structure.
957  */
958 void mei_hbm_pg_resume(struct mei_device *dev)
959 {
960 	pm_request_resume(dev->dev);
961 }
962 EXPORT_SYMBOL_GPL(mei_hbm_pg_resume);
963 
964 /**
965  * mei_hbm_pg_exit_res - PG exit response received
966  *
967  * @dev: the device structure.
968  *
969  * Return: 0 on success, -EPROTO on state mismatch
970  */
971 static int mei_hbm_pg_exit_res(struct mei_device *dev)
972 {
973 	if (mei_pg_state(dev) != MEI_PG_ON ||
974 	    (dev->pg_event != MEI_PG_EVENT_WAIT &&
975 	     dev->pg_event != MEI_PG_EVENT_IDLE)) {
976 		dev_err(dev->dev, "hbm: pg exit response: state mismatch [%s, %d]\n",
977 			mei_pg_state_str(mei_pg_state(dev)), dev->pg_event);
978 		return -EPROTO;
979 	}
980 
981 	switch (dev->pg_event) {
982 	case MEI_PG_EVENT_WAIT:
983 		dev->pg_event = MEI_PG_EVENT_RECEIVED;
984 		wake_up(&dev->wait_pg);
985 		break;
986 	case MEI_PG_EVENT_IDLE:
987 		/*
988 		* If the driver is not waiting on this then
989 		* this is HW initiated exit from PG.
990 		* Start runtime pm resume sequence to exit from PG.
991 		*/
992 		dev->pg_event = MEI_PG_EVENT_RECEIVED;
993 		mei_hbm_pg_resume(dev);
994 		break;
995 	default:
996 		WARN(1, "hbm: pg exit response: unexpected pg event = %d\n",
997 		     dev->pg_event);
998 		return -EPROTO;
999 	}
1000 
1001 	return 0;
1002 }
1003 
1004 /**
1005  * mei_hbm_config_features - check what hbm features and commands
1006  *        are supported by the fw
1007  *
1008  * @dev: the device structure
1009  */
1010 static void mei_hbm_config_features(struct mei_device *dev)
1011 {
1012 	/* Power Gating Isolation Support */
1013 	dev->hbm_f_pg_supported = 0;
1014 	if (dev->version.major_version > HBM_MAJOR_VERSION_PGI)
1015 		dev->hbm_f_pg_supported = 1;
1016 
1017 	if (dev->version.major_version == HBM_MAJOR_VERSION_PGI &&
1018 	    dev->version.minor_version >= HBM_MINOR_VERSION_PGI)
1019 		dev->hbm_f_pg_supported = 1;
1020 
1021 	dev->hbm_f_dc_supported = 0;
1022 	if (dev->version.major_version >= HBM_MAJOR_VERSION_DC)
1023 		dev->hbm_f_dc_supported = 1;
1024 
1025 	dev->hbm_f_ie_supported = 0;
1026 	if (dev->version.major_version >= HBM_MAJOR_VERSION_IE)
1027 		dev->hbm_f_ie_supported = 1;
1028 
1029 	/* disconnect on connect timeout instead of link reset */
1030 	dev->hbm_f_dot_supported = 0;
1031 	if (dev->version.major_version >= HBM_MAJOR_VERSION_DOT)
1032 		dev->hbm_f_dot_supported = 1;
1033 
1034 	/* Notification Event Support */
1035 	dev->hbm_f_ev_supported = 0;
1036 	if (dev->version.major_version >= HBM_MAJOR_VERSION_EV)
1037 		dev->hbm_f_ev_supported = 1;
1038 
1039 	/* Fixed Address Client Support */
1040 	dev->hbm_f_fa_supported = 0;
1041 	if (dev->version.major_version >= HBM_MAJOR_VERSION_FA)
1042 		dev->hbm_f_fa_supported = 1;
1043 
1044 	/* OS ver message Support */
1045 	dev->hbm_f_os_supported = 0;
1046 	if (dev->version.major_version >= HBM_MAJOR_VERSION_OS)
1047 		dev->hbm_f_os_supported = 1;
1048 
1049 	/* DMA Ring Support */
1050 	dev->hbm_f_dr_supported = 0;
1051 	if (dev->version.major_version > HBM_MAJOR_VERSION_DR ||
1052 	    (dev->version.major_version == HBM_MAJOR_VERSION_DR &&
1053 	     dev->version.minor_version >= HBM_MINOR_VERSION_DR))
1054 		dev->hbm_f_dr_supported = 1;
1055 }
1056 
1057 /**
1058  * mei_hbm_version_is_supported - checks whether the driver can
1059  *     support the hbm version of the device
1060  *
1061  * @dev: the device structure
1062  * Return: true if driver can support hbm version of the device
1063  */
1064 bool mei_hbm_version_is_supported(struct mei_device *dev)
1065 {
1066 	return	(dev->version.major_version < HBM_MAJOR_VERSION) ||
1067 		(dev->version.major_version == HBM_MAJOR_VERSION &&
1068 		 dev->version.minor_version <= HBM_MINOR_VERSION);
1069 }
1070 
1071 /**
1072  * mei_hbm_dispatch - bottom half read routine after ISR to
1073  * handle the read bus message cmd processing.
1074  *
1075  * @dev: the device structure
1076  * @hdr: header of bus message
1077  *
1078  * Return: 0 on success and < 0 on failure
1079  */
1080 int mei_hbm_dispatch(struct mei_device *dev, struct mei_msg_hdr *hdr)
1081 {
1082 	struct mei_bus_message *mei_msg;
1083 	struct hbm_host_version_response *version_res;
1084 	struct hbm_props_response *props_res;
1085 	struct hbm_host_enum_response *enum_res;
1086 	struct hbm_dma_setup_response *dma_setup_res;
1087 	struct hbm_add_client_request *add_cl_req;
1088 	int ret;
1089 
1090 	struct mei_hbm_cl_cmd *cl_cmd;
1091 	struct hbm_client_connect_request *disconnect_req;
1092 	struct hbm_flow_control *fctrl;
1093 
1094 	/* read the message to our buffer */
1095 	BUG_ON(hdr->length >= sizeof(dev->rd_msg_buf));
1096 	mei_read_slots(dev, dev->rd_msg_buf, hdr->length);
1097 	mei_msg = (struct mei_bus_message *)dev->rd_msg_buf;
1098 	cl_cmd  = (struct mei_hbm_cl_cmd *)mei_msg;
1099 
1100 	/* ignore spurious message and prevent reset nesting
1101 	 * hbm is put to idle during system reset
1102 	 */
1103 	if (dev->hbm_state == MEI_HBM_IDLE) {
1104 		dev_dbg(dev->dev, "hbm: state is idle ignore spurious messages\n");
1105 		return 0;
1106 	}
1107 
1108 	switch (mei_msg->hbm_cmd) {
1109 	case HOST_START_RES_CMD:
1110 		dev_dbg(dev->dev, "hbm: start: response message received.\n");
1111 
1112 		dev->init_clients_timer = 0;
1113 
1114 		version_res = (struct hbm_host_version_response *)mei_msg;
1115 
1116 		dev_dbg(dev->dev, "HBM VERSION: DRIVER=%02d:%02d DEVICE=%02d:%02d\n",
1117 				HBM_MAJOR_VERSION, HBM_MINOR_VERSION,
1118 				version_res->me_max_version.major_version,
1119 				version_res->me_max_version.minor_version);
1120 
1121 		if (version_res->host_version_supported) {
1122 			dev->version.major_version = HBM_MAJOR_VERSION;
1123 			dev->version.minor_version = HBM_MINOR_VERSION;
1124 		} else {
1125 			dev->version.major_version =
1126 				version_res->me_max_version.major_version;
1127 			dev->version.minor_version =
1128 				version_res->me_max_version.minor_version;
1129 		}
1130 
1131 		if (!mei_hbm_version_is_supported(dev)) {
1132 			dev_warn(dev->dev, "hbm: start: version mismatch - stopping the driver.\n");
1133 
1134 			dev->hbm_state = MEI_HBM_STOPPED;
1135 			if (mei_hbm_stop_req(dev)) {
1136 				dev_err(dev->dev, "hbm: start: failed to send stop request\n");
1137 				return -EIO;
1138 			}
1139 			break;
1140 		}
1141 
1142 		mei_hbm_config_features(dev);
1143 
1144 		if (dev->dev_state != MEI_DEV_INIT_CLIENTS ||
1145 		    dev->hbm_state != MEI_HBM_STARTING) {
1146 			dev_err(dev->dev, "hbm: start: state mismatch, [%d, %d]\n",
1147 				dev->dev_state, dev->hbm_state);
1148 			return -EPROTO;
1149 		}
1150 
1151 		if (dev->hbm_f_dr_supported) {
1152 			if (mei_dmam_ring_alloc(dev))
1153 				dev_info(dev->dev, "running w/o dma ring\n");
1154 			if (mei_dma_ring_is_allocated(dev)) {
1155 				if (mei_hbm_dma_setup_req(dev))
1156 					return -EIO;
1157 
1158 				wake_up(&dev->wait_hbm_start);
1159 				break;
1160 			}
1161 		}
1162 
1163 		dev->hbm_f_dr_supported = 0;
1164 		mei_dmam_ring_free(dev);
1165 
1166 		if (mei_hbm_enum_clients_req(dev))
1167 			return -EIO;
1168 
1169 		wake_up(&dev->wait_hbm_start);
1170 		break;
1171 
1172 	case MEI_HBM_DMA_SETUP_RES_CMD:
1173 		dev_dbg(dev->dev, "hbm: dma setup response: message received.\n");
1174 
1175 		dev->init_clients_timer = 0;
1176 
1177 		if (dev->hbm_state != MEI_HBM_DR_SETUP) {
1178 			dev_err(dev->dev, "hbm: dma setup response: state mismatch, [%d, %d]\n",
1179 				dev->dev_state, dev->hbm_state);
1180 			return -EPROTO;
1181 		}
1182 
1183 		dma_setup_res = (struct hbm_dma_setup_response *)mei_msg;
1184 
1185 		if (dma_setup_res->status) {
1186 			u8 status = dma_setup_res->status;
1187 
1188 			if (status == MEI_HBMS_NOT_ALLOWED) {
1189 				dev_dbg(dev->dev, "hbm: dma setup not allowed\n");
1190 			} else {
1191 				dev_info(dev->dev, "hbm: dma setup response: failure = %d %s\n",
1192 					 status,
1193 					 mei_hbm_status_str(status));
1194 			}
1195 			dev->hbm_f_dr_supported = 0;
1196 			mei_dmam_ring_free(dev);
1197 		}
1198 
1199 		if (mei_hbm_enum_clients_req(dev))
1200 			return -EIO;
1201 		break;
1202 
1203 	case CLIENT_CONNECT_RES_CMD:
1204 		dev_dbg(dev->dev, "hbm: client connect response: message received.\n");
1205 		mei_hbm_cl_res(dev, cl_cmd, MEI_FOP_CONNECT);
1206 		break;
1207 
1208 	case CLIENT_DISCONNECT_RES_CMD:
1209 		dev_dbg(dev->dev, "hbm: client disconnect response: message received.\n");
1210 		mei_hbm_cl_res(dev, cl_cmd, MEI_FOP_DISCONNECT);
1211 		break;
1212 
1213 	case MEI_FLOW_CONTROL_CMD:
1214 		dev_dbg(dev->dev, "hbm: client flow control response: message received.\n");
1215 
1216 		fctrl = (struct hbm_flow_control *)mei_msg;
1217 		mei_hbm_cl_tx_flow_ctrl_creds_res(dev, fctrl);
1218 		break;
1219 
1220 	case MEI_PG_ISOLATION_ENTRY_RES_CMD:
1221 		dev_dbg(dev->dev, "hbm: power gate isolation entry response received\n");
1222 		ret = mei_hbm_pg_enter_res(dev);
1223 		if (ret)
1224 			return ret;
1225 		break;
1226 
1227 	case MEI_PG_ISOLATION_EXIT_REQ_CMD:
1228 		dev_dbg(dev->dev, "hbm: power gate isolation exit request received\n");
1229 		ret = mei_hbm_pg_exit_res(dev);
1230 		if (ret)
1231 			return ret;
1232 		break;
1233 
1234 	case HOST_CLIENT_PROPERTIES_RES_CMD:
1235 		dev_dbg(dev->dev, "hbm: properties response: message received.\n");
1236 
1237 		dev->init_clients_timer = 0;
1238 
1239 		if (dev->dev_state != MEI_DEV_INIT_CLIENTS ||
1240 		    dev->hbm_state != MEI_HBM_CLIENT_PROPERTIES) {
1241 			dev_err(dev->dev, "hbm: properties response: state mismatch, [%d, %d]\n",
1242 				dev->dev_state, dev->hbm_state);
1243 			return -EPROTO;
1244 		}
1245 
1246 		props_res = (struct hbm_props_response *)mei_msg;
1247 
1248 		if (props_res->status == MEI_HBMS_CLIENT_NOT_FOUND) {
1249 			dev_dbg(dev->dev, "hbm: properties response: %d CLIENT_NOT_FOUND\n",
1250 				props_res->me_addr);
1251 		} else if (props_res->status) {
1252 			dev_err(dev->dev, "hbm: properties response: wrong status = %d %s\n",
1253 				props_res->status,
1254 				mei_hbm_status_str(props_res->status));
1255 			return -EPROTO;
1256 		} else {
1257 			mei_hbm_me_cl_add(dev, props_res);
1258 		}
1259 
1260 		/* request property for the next client */
1261 		if (mei_hbm_prop_req(dev, props_res->me_addr + 1))
1262 			return -EIO;
1263 
1264 		break;
1265 
1266 	case HOST_ENUM_RES_CMD:
1267 		dev_dbg(dev->dev, "hbm: enumeration response: message received\n");
1268 
1269 		dev->init_clients_timer = 0;
1270 
1271 		enum_res = (struct hbm_host_enum_response *) mei_msg;
1272 		BUILD_BUG_ON(sizeof(dev->me_clients_map)
1273 				< sizeof(enum_res->valid_addresses));
1274 		memcpy(dev->me_clients_map, enum_res->valid_addresses,
1275 				sizeof(enum_res->valid_addresses));
1276 
1277 		if (dev->dev_state != MEI_DEV_INIT_CLIENTS ||
1278 		    dev->hbm_state != MEI_HBM_ENUM_CLIENTS) {
1279 			dev_err(dev->dev, "hbm: enumeration response: state mismatch, [%d, %d]\n",
1280 				dev->dev_state, dev->hbm_state);
1281 			return -EPROTO;
1282 		}
1283 
1284 		dev->hbm_state = MEI_HBM_CLIENT_PROPERTIES;
1285 
1286 		/* first property request */
1287 		if (mei_hbm_prop_req(dev, 0))
1288 			return -EIO;
1289 
1290 		break;
1291 
1292 	case HOST_STOP_RES_CMD:
1293 		dev_dbg(dev->dev, "hbm: stop response: message received\n");
1294 
1295 		dev->init_clients_timer = 0;
1296 
1297 		if (dev->hbm_state != MEI_HBM_STOPPED) {
1298 			dev_err(dev->dev, "hbm: stop response: state mismatch, [%d, %d]\n",
1299 				dev->dev_state, dev->hbm_state);
1300 			return -EPROTO;
1301 		}
1302 
1303 		dev->dev_state = MEI_DEV_POWER_DOWN;
1304 		dev_info(dev->dev, "hbm: stop response: resetting.\n");
1305 		/* force the reset */
1306 		return -EPROTO;
1307 		break;
1308 
1309 	case CLIENT_DISCONNECT_REQ_CMD:
1310 		dev_dbg(dev->dev, "hbm: disconnect request: message received\n");
1311 
1312 		disconnect_req = (struct hbm_client_connect_request *)mei_msg;
1313 		mei_hbm_fw_disconnect_req(dev, disconnect_req);
1314 		break;
1315 
1316 	case ME_STOP_REQ_CMD:
1317 		dev_dbg(dev->dev, "hbm: stop request: message received\n");
1318 		dev->hbm_state = MEI_HBM_STOPPED;
1319 		if (mei_hbm_stop_req(dev)) {
1320 			dev_err(dev->dev, "hbm: stop request: failed to send stop request\n");
1321 			return -EIO;
1322 		}
1323 		break;
1324 
1325 	case MEI_HBM_ADD_CLIENT_REQ_CMD:
1326 		dev_dbg(dev->dev, "hbm: add client request received\n");
1327 		/*
1328 		 * after the host receives the enum_resp
1329 		 * message clients may be added or removed
1330 		 */
1331 		if (dev->hbm_state <= MEI_HBM_ENUM_CLIENTS ||
1332 		    dev->hbm_state >= MEI_HBM_STOPPED) {
1333 			dev_err(dev->dev, "hbm: add client: state mismatch, [%d, %d]\n",
1334 				dev->dev_state, dev->hbm_state);
1335 			return -EPROTO;
1336 		}
1337 		add_cl_req = (struct hbm_add_client_request *)mei_msg;
1338 		ret = mei_hbm_fw_add_cl_req(dev, add_cl_req);
1339 		if (ret) {
1340 			dev_err(dev->dev, "hbm: add client: failed to send response %d\n",
1341 				ret);
1342 			return -EIO;
1343 		}
1344 		dev_dbg(dev->dev, "hbm: add client request processed\n");
1345 		break;
1346 
1347 	case MEI_HBM_NOTIFY_RES_CMD:
1348 		dev_dbg(dev->dev, "hbm: notify response received\n");
1349 		mei_hbm_cl_res(dev, cl_cmd, notify_res_to_fop(cl_cmd));
1350 		break;
1351 
1352 	case MEI_HBM_NOTIFICATION_CMD:
1353 		dev_dbg(dev->dev, "hbm: notification\n");
1354 		mei_hbm_cl_notify(dev, cl_cmd);
1355 		break;
1356 
1357 	default:
1358 		WARN(1, "hbm: wrong command %d\n", mei_msg->hbm_cmd);
1359 		return -EPROTO;
1360 
1361 	}
1362 	return 0;
1363 }
1364 
1365