xref: /openbmc/linux/drivers/misc/mei/hbm.c (revision 29c37341)
1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  * Copyright (c) 2003-2020, 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 req;
261 	int ret;
262 
263 	mei_hbm_reset(dev);
264 
265 	mei_hbm_hdr(&mei_hdr, sizeof(req));
266 
267 	/* host start message */
268 	memset(&req, 0, sizeof(req));
269 	req.hbm_cmd = HOST_START_REQ_CMD;
270 	req.host_version.major_version = HBM_MAJOR_VERSION;
271 	req.host_version.minor_version = HBM_MINOR_VERSION;
272 
273 	dev->hbm_state = MEI_HBM_IDLE;
274 	ret = mei_hbm_write_message(dev, &mei_hdr, &req);
275 	if (ret) {
276 		dev_err(dev->dev, "version message write failed: ret = %d\n",
277 			ret);
278 		return ret;
279 	}
280 
281 	dev->hbm_state = MEI_HBM_STARTING;
282 	dev->init_clients_timer = MEI_CLIENTS_INIT_TIMEOUT;
283 	mei_schedule_stall_timer(dev);
284 	return 0;
285 }
286 
287 /**
288  * mei_hbm_dma_setup_req() - setup DMA request
289  * @dev: the device structure
290  *
291  * Return: 0 on success and < 0 on failure
292  */
293 static int mei_hbm_dma_setup_req(struct mei_device *dev)
294 {
295 	struct mei_msg_hdr mei_hdr;
296 	struct hbm_dma_setup_request req;
297 	unsigned int i;
298 	int ret;
299 
300 	mei_hbm_hdr(&mei_hdr, sizeof(req));
301 
302 	memset(&req, 0, sizeof(req));
303 	req.hbm_cmd = MEI_HBM_DMA_SETUP_REQ_CMD;
304 	for (i = 0; i < DMA_DSCR_NUM; i++) {
305 		phys_addr_t paddr;
306 
307 		paddr = dev->dr_dscr[i].daddr;
308 		req.dma_dscr[i].addr_hi = upper_32_bits(paddr);
309 		req.dma_dscr[i].addr_lo = lower_32_bits(paddr);
310 		req.dma_dscr[i].size = dev->dr_dscr[i].size;
311 	}
312 
313 	mei_dma_ring_reset(dev);
314 
315 	ret = mei_hbm_write_message(dev, &mei_hdr, &req);
316 	if (ret) {
317 		dev_err(dev->dev, "dma setup request write failed: ret = %d.\n",
318 			ret);
319 		return ret;
320 	}
321 
322 	dev->hbm_state = MEI_HBM_DR_SETUP;
323 	dev->init_clients_timer = MEI_CLIENTS_INIT_TIMEOUT;
324 	mei_schedule_stall_timer(dev);
325 	return 0;
326 }
327 
328 /**
329  * mei_hbm_enum_clients_req - sends enumeration client request message.
330  *
331  * @dev: the device structure
332  *
333  * Return: 0 on success and < 0 on failure
334  */
335 static int mei_hbm_enum_clients_req(struct mei_device *dev)
336 {
337 	struct mei_msg_hdr mei_hdr;
338 	struct hbm_host_enum_request req;
339 	int ret;
340 
341 	/* enumerate clients */
342 	mei_hbm_hdr(&mei_hdr, sizeof(req));
343 
344 	memset(&req, 0, sizeof(req));
345 	req.hbm_cmd = HOST_ENUM_REQ_CMD;
346 	req.flags |= dev->hbm_f_dc_supported ? MEI_HBM_ENUM_F_ALLOW_ADD : 0;
347 	req.flags |= dev->hbm_f_ie_supported ?
348 			  MEI_HBM_ENUM_F_IMMEDIATE_ENUM : 0;
349 
350 	ret = mei_hbm_write_message(dev, &mei_hdr, &req);
351 	if (ret) {
352 		dev_err(dev->dev, "enumeration request write failed: ret = %d.\n",
353 			ret);
354 		return ret;
355 	}
356 	dev->hbm_state = MEI_HBM_ENUM_CLIENTS;
357 	dev->init_clients_timer = MEI_CLIENTS_INIT_TIMEOUT;
358 	mei_schedule_stall_timer(dev);
359 	return 0;
360 }
361 
362 /**
363  * mei_hbm_me_cl_add - add new me client to the list
364  *
365  * @dev: the device structure
366  * @res: hbm property response
367  *
368  * Return: 0 on success and -ENOMEM on allocation failure
369  */
370 
371 static int mei_hbm_me_cl_add(struct mei_device *dev,
372 			     struct hbm_props_response *res)
373 {
374 	struct mei_me_client *me_cl;
375 	const uuid_le *uuid = &res->client_properties.protocol_name;
376 
377 	mei_me_cl_rm_by_uuid(dev, uuid);
378 
379 	me_cl = kzalloc(sizeof(*me_cl), GFP_KERNEL);
380 	if (!me_cl)
381 		return -ENOMEM;
382 
383 	mei_me_cl_init(me_cl);
384 
385 	me_cl->props = res->client_properties;
386 	me_cl->client_id = res->me_addr;
387 	me_cl->tx_flow_ctrl_creds = 0;
388 
389 	mei_me_cl_add(dev, me_cl);
390 
391 	return 0;
392 }
393 
394 /**
395  * mei_hbm_add_cl_resp - send response to fw on client add request
396  *
397  * @dev: the device structure
398  * @addr: me address
399  * @status: response status
400  *
401  * Return: 0 on success and < 0 on failure
402  */
403 static int mei_hbm_add_cl_resp(struct mei_device *dev, u8 addr, u8 status)
404 {
405 	struct mei_msg_hdr mei_hdr;
406 	struct hbm_add_client_response resp;
407 	int ret;
408 
409 	dev_dbg(dev->dev, "adding client response\n");
410 
411 	mei_hbm_hdr(&mei_hdr, sizeof(resp));
412 
413 	memset(&resp, 0, sizeof(resp));
414 	resp.hbm_cmd = MEI_HBM_ADD_CLIENT_RES_CMD;
415 	resp.me_addr = addr;
416 	resp.status  = status;
417 
418 	ret = mei_hbm_write_message(dev, &mei_hdr, &resp);
419 	if (ret)
420 		dev_err(dev->dev, "add client response write failed: ret = %d\n",
421 			ret);
422 	return ret;
423 }
424 
425 /**
426  * mei_hbm_fw_add_cl_req - request from the fw to add a client
427  *
428  * @dev: the device structure
429  * @req: add client request
430  *
431  * Return: 0 on success and < 0 on failure
432  */
433 static int mei_hbm_fw_add_cl_req(struct mei_device *dev,
434 			      struct hbm_add_client_request *req)
435 {
436 	int ret;
437 	u8 status = MEI_HBMS_SUCCESS;
438 
439 	BUILD_BUG_ON(sizeof(struct hbm_add_client_request) !=
440 			sizeof(struct hbm_props_response));
441 
442 	ret = mei_hbm_me_cl_add(dev, (struct hbm_props_response *)req);
443 	if (ret)
444 		status = !MEI_HBMS_SUCCESS;
445 
446 	if (dev->dev_state == MEI_DEV_ENABLED)
447 		schedule_work(&dev->bus_rescan_work);
448 
449 	return mei_hbm_add_cl_resp(dev, req->me_addr, status);
450 }
451 
452 /**
453  * mei_hbm_cl_notify_req - send notification request
454  *
455  * @dev: the device structure
456  * @cl: a client to disconnect from
457  * @start: true for start false for stop
458  *
459  * Return: 0 on success and -EIO on write failure
460  */
461 int mei_hbm_cl_notify_req(struct mei_device *dev,
462 			  struct mei_cl *cl, u8 start)
463 {
464 
465 	struct mei_msg_hdr mei_hdr;
466 	struct hbm_notification_request req;
467 	int ret;
468 
469 	mei_hbm_hdr(&mei_hdr, sizeof(req));
470 	mei_hbm_cl_hdr(cl, MEI_HBM_NOTIFY_REQ_CMD, &req, sizeof(req));
471 
472 	req.start = start;
473 
474 	ret = mei_hbm_write_message(dev, &mei_hdr, &req);
475 	if (ret)
476 		dev_err(dev->dev, "notify request failed: ret = %d\n", ret);
477 
478 	return ret;
479 }
480 
481 /**
482  *  notify_res_to_fop - convert notification response to the proper
483  *      notification FOP
484  *
485  * @cmd: client notification start response command
486  *
487  * Return:  MEI_FOP_NOTIFY_START or MEI_FOP_NOTIFY_STOP;
488  */
489 static inline enum mei_cb_file_ops notify_res_to_fop(struct mei_hbm_cl_cmd *cmd)
490 {
491 	struct hbm_notification_response *rs =
492 		(struct hbm_notification_response *)cmd;
493 
494 	return mei_cl_notify_req2fop(rs->start);
495 }
496 
497 /**
498  * mei_hbm_cl_notify_start_res - update the client state according
499  *       notify start response
500  *
501  * @dev: the device structure
502  * @cl: mei host client
503  * @cmd: client notification start response command
504  */
505 static void mei_hbm_cl_notify_start_res(struct mei_device *dev,
506 					struct mei_cl *cl,
507 					struct mei_hbm_cl_cmd *cmd)
508 {
509 	struct hbm_notification_response *rs =
510 		(struct hbm_notification_response *)cmd;
511 
512 	cl_dbg(dev, cl, "hbm: notify start response status=%d\n", rs->status);
513 
514 	if (rs->status == MEI_HBMS_SUCCESS ||
515 	    rs->status == MEI_HBMS_ALREADY_STARTED) {
516 		cl->notify_en = true;
517 		cl->status = 0;
518 	} else {
519 		cl->status = -EINVAL;
520 	}
521 }
522 
523 /**
524  * mei_hbm_cl_notify_stop_res - update the client state according
525  *       notify stop response
526  *
527  * @dev: the device structure
528  * @cl: mei host client
529  * @cmd: client notification stop response command
530  */
531 static void mei_hbm_cl_notify_stop_res(struct mei_device *dev,
532 				       struct mei_cl *cl,
533 				       struct mei_hbm_cl_cmd *cmd)
534 {
535 	struct hbm_notification_response *rs =
536 		(struct hbm_notification_response *)cmd;
537 
538 	cl_dbg(dev, cl, "hbm: notify stop response status=%d\n", rs->status);
539 
540 	if (rs->status == MEI_HBMS_SUCCESS ||
541 	    rs->status == MEI_HBMS_NOT_STARTED) {
542 		cl->notify_en = false;
543 		cl->status = 0;
544 	} else {
545 		/* TODO: spec is not clear yet about other possible issues */
546 		cl->status = -EINVAL;
547 	}
548 }
549 
550 /**
551  * mei_hbm_cl_notify - signal notification event
552  *
553  * @dev: the device structure
554  * @cmd: notification client message
555  */
556 static void mei_hbm_cl_notify(struct mei_device *dev,
557 			      struct mei_hbm_cl_cmd *cmd)
558 {
559 	struct mei_cl *cl;
560 
561 	cl = mei_hbm_cl_find_by_cmd(dev, cmd);
562 	if (cl)
563 		mei_cl_notify(cl);
564 }
565 
566 /**
567  * mei_hbm_prop_req - request property for a single client
568  *
569  * @dev: the device structure
570  * @start_idx: client index to start search
571  *
572  * Return: 0 on success and < 0 on failure
573  */
574 static int mei_hbm_prop_req(struct mei_device *dev, unsigned long start_idx)
575 {
576 	struct mei_msg_hdr mei_hdr;
577 	struct hbm_props_request req;
578 	unsigned long addr;
579 	int ret;
580 
581 	addr = find_next_bit(dev->me_clients_map, MEI_CLIENTS_MAX, start_idx);
582 
583 	/* We got all client properties */
584 	if (addr == MEI_CLIENTS_MAX) {
585 		dev->hbm_state = MEI_HBM_STARTED;
586 		mei_host_client_init(dev);
587 		return 0;
588 	}
589 
590 	mei_hbm_hdr(&mei_hdr, sizeof(req));
591 
592 	memset(&req, 0, sizeof(req));
593 
594 	req.hbm_cmd = HOST_CLIENT_PROPERTIES_REQ_CMD;
595 	req.me_addr = addr;
596 
597 	ret = mei_hbm_write_message(dev, &mei_hdr, &req);
598 	if (ret) {
599 		dev_err(dev->dev, "properties request write failed: ret = %d\n",
600 			ret);
601 		return ret;
602 	}
603 
604 	dev->init_clients_timer = MEI_CLIENTS_INIT_TIMEOUT;
605 	mei_schedule_stall_timer(dev);
606 
607 	return 0;
608 }
609 
610 /**
611  * mei_hbm_pg - sends pg command
612  *
613  * @dev: the device structure
614  * @pg_cmd: the pg command code
615  *
616  * Return: -EIO on write failure
617  *         -EOPNOTSUPP if the operation is not supported by the protocol
618  */
619 int mei_hbm_pg(struct mei_device *dev, u8 pg_cmd)
620 {
621 	struct mei_msg_hdr mei_hdr;
622 	struct hbm_power_gate req;
623 	int ret;
624 
625 	if (!dev->hbm_f_pg_supported)
626 		return -EOPNOTSUPP;
627 
628 	mei_hbm_hdr(&mei_hdr, sizeof(req));
629 
630 	memset(&req, 0, sizeof(req));
631 	req.hbm_cmd = pg_cmd;
632 
633 	ret = mei_hbm_write_message(dev, &mei_hdr, &req);
634 	if (ret)
635 		dev_err(dev->dev, "power gate command write failed.\n");
636 	return ret;
637 }
638 EXPORT_SYMBOL_GPL(mei_hbm_pg);
639 
640 /**
641  * mei_hbm_stop_req - send stop request message
642  *
643  * @dev: mei device
644  *
645  * Return: -EIO on write failure
646  */
647 static int mei_hbm_stop_req(struct mei_device *dev)
648 {
649 	struct mei_msg_hdr mei_hdr;
650 	struct hbm_host_stop_request req;
651 
652 	mei_hbm_hdr(&mei_hdr, sizeof(req));
653 
654 	memset(&req, 0, sizeof(req));
655 	req.hbm_cmd = HOST_STOP_REQ_CMD;
656 	req.reason = DRIVER_STOP_REQUEST;
657 
658 	return mei_hbm_write_message(dev, &mei_hdr, &req);
659 }
660 
661 /**
662  * mei_hbm_cl_flow_control_req - sends flow control request.
663  *
664  * @dev: the device structure
665  * @cl: client info
666  *
667  * Return: -EIO on write failure
668  */
669 int mei_hbm_cl_flow_control_req(struct mei_device *dev, struct mei_cl *cl)
670 {
671 	struct hbm_flow_control req;
672 
673 	cl_dbg(dev, cl, "sending flow control\n");
674 	return mei_hbm_cl_write(dev, cl, MEI_FLOW_CONTROL_CMD,
675 				&req, sizeof(req));
676 }
677 
678 /**
679  * mei_hbm_add_single_tx_flow_ctrl_creds - adds single buffer credentials.
680  *
681  * @dev: the device structure
682  * @fctrl: flow control response bus message
683  *
684  * Return: 0 on success, < 0 otherwise
685  */
686 static int mei_hbm_add_single_tx_flow_ctrl_creds(struct mei_device *dev,
687 						 struct hbm_flow_control *fctrl)
688 {
689 	struct mei_me_client *me_cl;
690 	int rets;
691 
692 	me_cl = mei_me_cl_by_id(dev, fctrl->me_addr);
693 	if (!me_cl) {
694 		dev_err(dev->dev, "no such me client %d\n", fctrl->me_addr);
695 		return -ENOENT;
696 	}
697 
698 	if (WARN_ON(me_cl->props.single_recv_buf == 0)) {
699 		rets = -EINVAL;
700 		goto out;
701 	}
702 
703 	me_cl->tx_flow_ctrl_creds++;
704 	dev_dbg(dev->dev, "recv flow ctrl msg ME %d (single) creds = %d.\n",
705 		fctrl->me_addr, me_cl->tx_flow_ctrl_creds);
706 
707 	rets = 0;
708 out:
709 	mei_me_cl_put(me_cl);
710 	return rets;
711 }
712 
713 /**
714  * mei_hbm_cl_flow_control_res - flow control response from me
715  *
716  * @dev: the device structure
717  * @fctrl: flow control response bus message
718  */
719 static void mei_hbm_cl_tx_flow_ctrl_creds_res(struct mei_device *dev,
720 					       struct hbm_flow_control *fctrl)
721 {
722 	struct mei_cl *cl;
723 
724 	if (!fctrl->host_addr) {
725 		/* single receive buffer */
726 		mei_hbm_add_single_tx_flow_ctrl_creds(dev, fctrl);
727 		return;
728 	}
729 
730 	cl = mei_hbm_cl_find_by_cmd(dev, fctrl);
731 	if (cl) {
732 		cl->tx_flow_ctrl_creds++;
733 		cl_dbg(dev, cl, "flow control creds = %d.\n",
734 				cl->tx_flow_ctrl_creds);
735 	}
736 }
737 
738 
739 /**
740  * mei_hbm_cl_disconnect_req - sends disconnect message to fw.
741  *
742  * @dev: the device structure
743  * @cl: a client to disconnect from
744  *
745  * Return: -EIO on write failure
746  */
747 int mei_hbm_cl_disconnect_req(struct mei_device *dev, struct mei_cl *cl)
748 {
749 	struct hbm_client_connect_request req;
750 
751 	return mei_hbm_cl_write(dev, cl, CLIENT_DISCONNECT_REQ_CMD,
752 				&req, sizeof(req));
753 }
754 
755 /**
756  * mei_hbm_cl_disconnect_rsp - sends disconnect respose to the FW
757  *
758  * @dev: the device structure
759  * @cl: a client to disconnect from
760  *
761  * Return: -EIO on write failure
762  */
763 int mei_hbm_cl_disconnect_rsp(struct mei_device *dev, struct mei_cl *cl)
764 {
765 	struct hbm_client_connect_response resp;
766 
767 	return mei_hbm_cl_write(dev, cl, CLIENT_DISCONNECT_RES_CMD,
768 				&resp, sizeof(resp));
769 }
770 
771 /**
772  * mei_hbm_cl_disconnect_res - update the client state according
773  *       disconnect response
774  *
775  * @dev: the device structure
776  * @cl: mei host client
777  * @cmd: disconnect client response host bus message
778  */
779 static void mei_hbm_cl_disconnect_res(struct mei_device *dev, struct mei_cl *cl,
780 				      struct mei_hbm_cl_cmd *cmd)
781 {
782 	struct hbm_client_connect_response *rs =
783 		(struct hbm_client_connect_response *)cmd;
784 
785 	cl_dbg(dev, cl, "hbm: disconnect response status=%d\n", rs->status);
786 
787 	if (rs->status == MEI_CL_DISCONN_SUCCESS)
788 		cl->state = MEI_FILE_DISCONNECT_REPLY;
789 	cl->status = 0;
790 }
791 
792 /**
793  * mei_hbm_cl_connect_req - send connection request to specific me client
794  *
795  * @dev: the device structure
796  * @cl: a client to connect to
797  *
798  * Return: -EIO on write failure
799  */
800 int mei_hbm_cl_connect_req(struct mei_device *dev, struct mei_cl *cl)
801 {
802 	struct hbm_client_connect_request req;
803 
804 	return mei_hbm_cl_write(dev, cl, CLIENT_CONNECT_REQ_CMD,
805 				&req, sizeof(req));
806 }
807 
808 /**
809  * mei_hbm_cl_connect_res - update the client state according
810  *        connection response
811  *
812  * @dev: the device structure
813  * @cl: mei host client
814  * @cmd: connect client response host bus message
815  */
816 static void mei_hbm_cl_connect_res(struct mei_device *dev, struct mei_cl *cl,
817 				   struct mei_hbm_cl_cmd *cmd)
818 {
819 	struct hbm_client_connect_response *rs =
820 		(struct hbm_client_connect_response *)cmd;
821 
822 	cl_dbg(dev, cl, "hbm: connect response status=%s\n",
823 			mei_cl_conn_status_str(rs->status));
824 
825 	if (rs->status == MEI_CL_CONN_SUCCESS)
826 		cl->state = MEI_FILE_CONNECTED;
827 	else {
828 		cl->state = MEI_FILE_DISCONNECT_REPLY;
829 		if (rs->status == MEI_CL_CONN_NOT_FOUND) {
830 			mei_me_cl_del(dev, cl->me_cl);
831 			if (dev->dev_state == MEI_DEV_ENABLED)
832 				schedule_work(&dev->bus_rescan_work);
833 		}
834 	}
835 	cl->status = mei_cl_conn_status_to_errno(rs->status);
836 }
837 
838 /**
839  * mei_hbm_cl_res - process hbm response received on behalf
840  *         an client
841  *
842  * @dev: the device structure
843  * @rs:  hbm client message
844  * @fop_type: file operation type
845  */
846 static void mei_hbm_cl_res(struct mei_device *dev,
847 			   struct mei_hbm_cl_cmd *rs,
848 			   enum mei_cb_file_ops fop_type)
849 {
850 	struct mei_cl *cl;
851 	struct mei_cl_cb *cb, *next;
852 
853 	cl = NULL;
854 	list_for_each_entry_safe(cb, next, &dev->ctrl_rd_list, list) {
855 
856 		cl = cb->cl;
857 
858 		if (cb->fop_type != fop_type)
859 			continue;
860 
861 		if (mei_hbm_cl_addr_equal(cl, rs)) {
862 			list_del_init(&cb->list);
863 			break;
864 		}
865 	}
866 
867 	if (!cl)
868 		return;
869 
870 	switch (fop_type) {
871 	case MEI_FOP_CONNECT:
872 		mei_hbm_cl_connect_res(dev, cl, rs);
873 		break;
874 	case MEI_FOP_DISCONNECT:
875 		mei_hbm_cl_disconnect_res(dev, cl, rs);
876 		break;
877 	case MEI_FOP_NOTIFY_START:
878 		mei_hbm_cl_notify_start_res(dev, cl, rs);
879 		break;
880 	case MEI_FOP_NOTIFY_STOP:
881 		mei_hbm_cl_notify_stop_res(dev, cl, rs);
882 		break;
883 	default:
884 		return;
885 	}
886 
887 	cl->timer_count = 0;
888 	wake_up(&cl->wait);
889 }
890 
891 
892 /**
893  * mei_hbm_fw_disconnect_req - disconnect request initiated by ME firmware
894  *  host sends disconnect response
895  *
896  * @dev: the device structure.
897  * @disconnect_req: disconnect request bus message from the me
898  *
899  * Return: -ENOMEM on allocation failure
900  */
901 static int mei_hbm_fw_disconnect_req(struct mei_device *dev,
902 		struct hbm_client_connect_request *disconnect_req)
903 {
904 	struct mei_cl *cl;
905 	struct mei_cl_cb *cb;
906 
907 	cl = mei_hbm_cl_find_by_cmd(dev, disconnect_req);
908 	if (cl) {
909 		cl_warn(dev, cl, "fw disconnect request received\n");
910 		cl->state = MEI_FILE_DISCONNECTING;
911 		cl->timer_count = 0;
912 
913 		cb = mei_cl_enqueue_ctrl_wr_cb(cl, 0, MEI_FOP_DISCONNECT_RSP,
914 					       NULL);
915 		if (!cb)
916 			return -ENOMEM;
917 	}
918 	return 0;
919 }
920 
921 /**
922  * mei_hbm_pg_enter_res - PG enter response received
923  *
924  * @dev: the device structure.
925  *
926  * Return: 0 on success, -EPROTO on state mismatch
927  */
928 static int mei_hbm_pg_enter_res(struct mei_device *dev)
929 {
930 	if (mei_pg_state(dev) != MEI_PG_OFF ||
931 	    dev->pg_event != MEI_PG_EVENT_WAIT) {
932 		dev_err(dev->dev, "hbm: pg entry response: state mismatch [%s, %d]\n",
933 			mei_pg_state_str(mei_pg_state(dev)), dev->pg_event);
934 		return -EPROTO;
935 	}
936 
937 	dev->pg_event = MEI_PG_EVENT_RECEIVED;
938 	wake_up(&dev->wait_pg);
939 
940 	return 0;
941 }
942 
943 /**
944  * mei_hbm_pg_resume - process with PG resume
945  *
946  * @dev: the device structure.
947  */
948 void mei_hbm_pg_resume(struct mei_device *dev)
949 {
950 	pm_request_resume(dev->dev);
951 }
952 EXPORT_SYMBOL_GPL(mei_hbm_pg_resume);
953 
954 /**
955  * mei_hbm_pg_exit_res - PG exit response received
956  *
957  * @dev: the device structure.
958  *
959  * Return: 0 on success, -EPROTO on state mismatch
960  */
961 static int mei_hbm_pg_exit_res(struct mei_device *dev)
962 {
963 	if (mei_pg_state(dev) != MEI_PG_ON ||
964 	    (dev->pg_event != MEI_PG_EVENT_WAIT &&
965 	     dev->pg_event != MEI_PG_EVENT_IDLE)) {
966 		dev_err(dev->dev, "hbm: pg exit response: state mismatch [%s, %d]\n",
967 			mei_pg_state_str(mei_pg_state(dev)), dev->pg_event);
968 		return -EPROTO;
969 	}
970 
971 	switch (dev->pg_event) {
972 	case MEI_PG_EVENT_WAIT:
973 		dev->pg_event = MEI_PG_EVENT_RECEIVED;
974 		wake_up(&dev->wait_pg);
975 		break;
976 	case MEI_PG_EVENT_IDLE:
977 		/*
978 		* If the driver is not waiting on this then
979 		* this is HW initiated exit from PG.
980 		* Start runtime pm resume sequence to exit from PG.
981 		*/
982 		dev->pg_event = MEI_PG_EVENT_RECEIVED;
983 		mei_hbm_pg_resume(dev);
984 		break;
985 	default:
986 		WARN(1, "hbm: pg exit response: unexpected pg event = %d\n",
987 		     dev->pg_event);
988 		return -EPROTO;
989 	}
990 
991 	return 0;
992 }
993 
994 /**
995  * mei_hbm_config_features - check what hbm features and commands
996  *        are supported by the fw
997  *
998  * @dev: the device structure
999  */
1000 static void mei_hbm_config_features(struct mei_device *dev)
1001 {
1002 	/* Power Gating Isolation Support */
1003 	dev->hbm_f_pg_supported = 0;
1004 	if (dev->version.major_version > HBM_MAJOR_VERSION_PGI)
1005 		dev->hbm_f_pg_supported = 1;
1006 
1007 	if (dev->version.major_version == HBM_MAJOR_VERSION_PGI &&
1008 	    dev->version.minor_version >= HBM_MINOR_VERSION_PGI)
1009 		dev->hbm_f_pg_supported = 1;
1010 
1011 	dev->hbm_f_dc_supported = 0;
1012 	if (dev->version.major_version >= HBM_MAJOR_VERSION_DC)
1013 		dev->hbm_f_dc_supported = 1;
1014 
1015 	dev->hbm_f_ie_supported = 0;
1016 	if (dev->version.major_version >= HBM_MAJOR_VERSION_IE)
1017 		dev->hbm_f_ie_supported = 1;
1018 
1019 	/* disconnect on connect timeout instead of link reset */
1020 	dev->hbm_f_dot_supported = 0;
1021 	if (dev->version.major_version >= HBM_MAJOR_VERSION_DOT)
1022 		dev->hbm_f_dot_supported = 1;
1023 
1024 	/* Notification Event Support */
1025 	dev->hbm_f_ev_supported = 0;
1026 	if (dev->version.major_version >= HBM_MAJOR_VERSION_EV)
1027 		dev->hbm_f_ev_supported = 1;
1028 
1029 	/* Fixed Address Client Support */
1030 	dev->hbm_f_fa_supported = 0;
1031 	if (dev->version.major_version >= HBM_MAJOR_VERSION_FA)
1032 		dev->hbm_f_fa_supported = 1;
1033 
1034 	/* OS ver message Support */
1035 	dev->hbm_f_os_supported = 0;
1036 	if (dev->version.major_version >= HBM_MAJOR_VERSION_OS)
1037 		dev->hbm_f_os_supported = 1;
1038 
1039 	/* DMA Ring Support */
1040 	dev->hbm_f_dr_supported = 0;
1041 	if (dev->version.major_version > HBM_MAJOR_VERSION_DR ||
1042 	    (dev->version.major_version == HBM_MAJOR_VERSION_DR &&
1043 	     dev->version.minor_version >= HBM_MINOR_VERSION_DR))
1044 		dev->hbm_f_dr_supported = 1;
1045 }
1046 
1047 /**
1048  * mei_hbm_version_is_supported - checks whether the driver can
1049  *     support the hbm version of the device
1050  *
1051  * @dev: the device structure
1052  * Return: true if driver can support hbm version of the device
1053  */
1054 bool mei_hbm_version_is_supported(struct mei_device *dev)
1055 {
1056 	return	(dev->version.major_version < HBM_MAJOR_VERSION) ||
1057 		(dev->version.major_version == HBM_MAJOR_VERSION &&
1058 		 dev->version.minor_version <= HBM_MINOR_VERSION);
1059 }
1060 
1061 /**
1062  * mei_hbm_dispatch - bottom half read routine after ISR to
1063  * handle the read bus message cmd processing.
1064  *
1065  * @dev: the device structure
1066  * @hdr: header of bus message
1067  *
1068  * Return: 0 on success and < 0 on failure
1069  */
1070 int mei_hbm_dispatch(struct mei_device *dev, struct mei_msg_hdr *hdr)
1071 {
1072 	struct mei_bus_message *mei_msg;
1073 	struct hbm_host_version_response *version_res;
1074 	struct hbm_props_response *props_res;
1075 	struct hbm_host_enum_response *enum_res;
1076 	struct hbm_dma_setup_response *dma_setup_res;
1077 	struct hbm_add_client_request *add_cl_req;
1078 	int ret;
1079 
1080 	struct mei_hbm_cl_cmd *cl_cmd;
1081 	struct hbm_client_connect_request *disconnect_req;
1082 	struct hbm_flow_control *fctrl;
1083 
1084 	/* read the message to our buffer */
1085 	BUG_ON(hdr->length >= sizeof(dev->rd_msg_buf));
1086 	mei_read_slots(dev, dev->rd_msg_buf, hdr->length);
1087 	mei_msg = (struct mei_bus_message *)dev->rd_msg_buf;
1088 	cl_cmd  = (struct mei_hbm_cl_cmd *)mei_msg;
1089 
1090 	/* ignore spurious message and prevent reset nesting
1091 	 * hbm is put to idle during system reset
1092 	 */
1093 	if (dev->hbm_state == MEI_HBM_IDLE) {
1094 		dev_dbg(dev->dev, "hbm: state is idle ignore spurious messages\n");
1095 		return 0;
1096 	}
1097 
1098 	switch (mei_msg->hbm_cmd) {
1099 	case HOST_START_RES_CMD:
1100 		dev_dbg(dev->dev, "hbm: start: response message received.\n");
1101 
1102 		dev->init_clients_timer = 0;
1103 
1104 		version_res = (struct hbm_host_version_response *)mei_msg;
1105 
1106 		dev_dbg(dev->dev, "HBM VERSION: DRIVER=%02d:%02d DEVICE=%02d:%02d\n",
1107 				HBM_MAJOR_VERSION, HBM_MINOR_VERSION,
1108 				version_res->me_max_version.major_version,
1109 				version_res->me_max_version.minor_version);
1110 
1111 		if (version_res->host_version_supported) {
1112 			dev->version.major_version = HBM_MAJOR_VERSION;
1113 			dev->version.minor_version = HBM_MINOR_VERSION;
1114 		} else {
1115 			dev->version.major_version =
1116 				version_res->me_max_version.major_version;
1117 			dev->version.minor_version =
1118 				version_res->me_max_version.minor_version;
1119 		}
1120 
1121 		if (!mei_hbm_version_is_supported(dev)) {
1122 			dev_warn(dev->dev, "hbm: start: version mismatch - stopping the driver.\n");
1123 
1124 			dev->hbm_state = MEI_HBM_STOPPED;
1125 			if (mei_hbm_stop_req(dev)) {
1126 				dev_err(dev->dev, "hbm: start: failed to send stop request\n");
1127 				return -EIO;
1128 			}
1129 			break;
1130 		}
1131 
1132 		mei_hbm_config_features(dev);
1133 
1134 		if (dev->dev_state != MEI_DEV_INIT_CLIENTS ||
1135 		    dev->hbm_state != MEI_HBM_STARTING) {
1136 			dev_err(dev->dev, "hbm: start: state mismatch, [%d, %d]\n",
1137 				dev->dev_state, dev->hbm_state);
1138 			return -EPROTO;
1139 		}
1140 
1141 		if (dev->hbm_f_dr_supported) {
1142 			if (mei_dmam_ring_alloc(dev))
1143 				dev_info(dev->dev, "running w/o dma ring\n");
1144 			if (mei_dma_ring_is_allocated(dev)) {
1145 				if (mei_hbm_dma_setup_req(dev))
1146 					return -EIO;
1147 
1148 				wake_up(&dev->wait_hbm_start);
1149 				break;
1150 			}
1151 		}
1152 
1153 		dev->hbm_f_dr_supported = 0;
1154 		mei_dmam_ring_free(dev);
1155 
1156 		if (mei_hbm_enum_clients_req(dev))
1157 			return -EIO;
1158 
1159 		wake_up(&dev->wait_hbm_start);
1160 		break;
1161 
1162 	case MEI_HBM_DMA_SETUP_RES_CMD:
1163 		dev_dbg(dev->dev, "hbm: dma setup response: message received.\n");
1164 
1165 		dev->init_clients_timer = 0;
1166 
1167 		if (dev->hbm_state != MEI_HBM_DR_SETUP) {
1168 			dev_err(dev->dev, "hbm: dma setup response: state mismatch, [%d, %d]\n",
1169 				dev->dev_state, dev->hbm_state);
1170 			return -EPROTO;
1171 		}
1172 
1173 		dma_setup_res = (struct hbm_dma_setup_response *)mei_msg;
1174 
1175 		if (dma_setup_res->status) {
1176 			u8 status = dma_setup_res->status;
1177 
1178 			if (status == MEI_HBMS_NOT_ALLOWED) {
1179 				dev_dbg(dev->dev, "hbm: dma setup not allowed\n");
1180 			} else {
1181 				dev_info(dev->dev, "hbm: dma setup response: failure = %d %s\n",
1182 					 status,
1183 					 mei_hbm_status_str(status));
1184 			}
1185 			dev->hbm_f_dr_supported = 0;
1186 			mei_dmam_ring_free(dev);
1187 		}
1188 
1189 		if (mei_hbm_enum_clients_req(dev))
1190 			return -EIO;
1191 		break;
1192 
1193 	case CLIENT_CONNECT_RES_CMD:
1194 		dev_dbg(dev->dev, "hbm: client connect response: message received.\n");
1195 		mei_hbm_cl_res(dev, cl_cmd, MEI_FOP_CONNECT);
1196 		break;
1197 
1198 	case CLIENT_DISCONNECT_RES_CMD:
1199 		dev_dbg(dev->dev, "hbm: client disconnect response: message received.\n");
1200 		mei_hbm_cl_res(dev, cl_cmd, MEI_FOP_DISCONNECT);
1201 		break;
1202 
1203 	case MEI_FLOW_CONTROL_CMD:
1204 		dev_dbg(dev->dev, "hbm: client flow control response: message received.\n");
1205 
1206 		fctrl = (struct hbm_flow_control *)mei_msg;
1207 		mei_hbm_cl_tx_flow_ctrl_creds_res(dev, fctrl);
1208 		break;
1209 
1210 	case MEI_PG_ISOLATION_ENTRY_RES_CMD:
1211 		dev_dbg(dev->dev, "hbm: power gate isolation entry response received\n");
1212 		ret = mei_hbm_pg_enter_res(dev);
1213 		if (ret)
1214 			return ret;
1215 		break;
1216 
1217 	case MEI_PG_ISOLATION_EXIT_REQ_CMD:
1218 		dev_dbg(dev->dev, "hbm: power gate isolation exit request received\n");
1219 		ret = mei_hbm_pg_exit_res(dev);
1220 		if (ret)
1221 			return ret;
1222 		break;
1223 
1224 	case HOST_CLIENT_PROPERTIES_RES_CMD:
1225 		dev_dbg(dev->dev, "hbm: properties response: message received.\n");
1226 
1227 		dev->init_clients_timer = 0;
1228 
1229 		if (dev->dev_state != MEI_DEV_INIT_CLIENTS ||
1230 		    dev->hbm_state != MEI_HBM_CLIENT_PROPERTIES) {
1231 			dev_err(dev->dev, "hbm: properties response: state mismatch, [%d, %d]\n",
1232 				dev->dev_state, dev->hbm_state);
1233 			return -EPROTO;
1234 		}
1235 
1236 		props_res = (struct hbm_props_response *)mei_msg;
1237 
1238 		if (props_res->status == MEI_HBMS_CLIENT_NOT_FOUND) {
1239 			dev_dbg(dev->dev, "hbm: properties response: %d CLIENT_NOT_FOUND\n",
1240 				props_res->me_addr);
1241 		} else if (props_res->status) {
1242 			dev_err(dev->dev, "hbm: properties response: wrong status = %d %s\n",
1243 				props_res->status,
1244 				mei_hbm_status_str(props_res->status));
1245 			return -EPROTO;
1246 		} else {
1247 			mei_hbm_me_cl_add(dev, props_res);
1248 		}
1249 
1250 		/* request property for the next client */
1251 		if (mei_hbm_prop_req(dev, props_res->me_addr + 1))
1252 			return -EIO;
1253 
1254 		break;
1255 
1256 	case HOST_ENUM_RES_CMD:
1257 		dev_dbg(dev->dev, "hbm: enumeration response: message received\n");
1258 
1259 		dev->init_clients_timer = 0;
1260 
1261 		enum_res = (struct hbm_host_enum_response *) mei_msg;
1262 		BUILD_BUG_ON(sizeof(dev->me_clients_map)
1263 				< sizeof(enum_res->valid_addresses));
1264 		memcpy(dev->me_clients_map, enum_res->valid_addresses,
1265 				sizeof(enum_res->valid_addresses));
1266 
1267 		if (dev->dev_state != MEI_DEV_INIT_CLIENTS ||
1268 		    dev->hbm_state != MEI_HBM_ENUM_CLIENTS) {
1269 			dev_err(dev->dev, "hbm: enumeration response: state mismatch, [%d, %d]\n",
1270 				dev->dev_state, dev->hbm_state);
1271 			return -EPROTO;
1272 		}
1273 
1274 		dev->hbm_state = MEI_HBM_CLIENT_PROPERTIES;
1275 
1276 		/* first property request */
1277 		if (mei_hbm_prop_req(dev, 0))
1278 			return -EIO;
1279 
1280 		break;
1281 
1282 	case HOST_STOP_RES_CMD:
1283 		dev_dbg(dev->dev, "hbm: stop response: message received\n");
1284 
1285 		dev->init_clients_timer = 0;
1286 
1287 		if (dev->hbm_state != MEI_HBM_STOPPED) {
1288 			dev_err(dev->dev, "hbm: stop response: state mismatch, [%d, %d]\n",
1289 				dev->dev_state, dev->hbm_state);
1290 			return -EPROTO;
1291 		}
1292 
1293 		dev->dev_state = MEI_DEV_POWER_DOWN;
1294 		dev_info(dev->dev, "hbm: stop response: resetting.\n");
1295 		/* force the reset */
1296 		return -EPROTO;
1297 		break;
1298 
1299 	case CLIENT_DISCONNECT_REQ_CMD:
1300 		dev_dbg(dev->dev, "hbm: disconnect request: message received\n");
1301 
1302 		disconnect_req = (struct hbm_client_connect_request *)mei_msg;
1303 		mei_hbm_fw_disconnect_req(dev, disconnect_req);
1304 		break;
1305 
1306 	case ME_STOP_REQ_CMD:
1307 		dev_dbg(dev->dev, "hbm: stop request: message received\n");
1308 		dev->hbm_state = MEI_HBM_STOPPED;
1309 		if (mei_hbm_stop_req(dev)) {
1310 			dev_err(dev->dev, "hbm: stop request: failed to send stop request\n");
1311 			return -EIO;
1312 		}
1313 		break;
1314 
1315 	case MEI_HBM_ADD_CLIENT_REQ_CMD:
1316 		dev_dbg(dev->dev, "hbm: add client request received\n");
1317 		/*
1318 		 * after the host receives the enum_resp
1319 		 * message clients may be added or removed
1320 		 */
1321 		if (dev->hbm_state <= MEI_HBM_ENUM_CLIENTS ||
1322 		    dev->hbm_state >= MEI_HBM_STOPPED) {
1323 			dev_err(dev->dev, "hbm: add client: state mismatch, [%d, %d]\n",
1324 				dev->dev_state, dev->hbm_state);
1325 			return -EPROTO;
1326 		}
1327 		add_cl_req = (struct hbm_add_client_request *)mei_msg;
1328 		ret = mei_hbm_fw_add_cl_req(dev, add_cl_req);
1329 		if (ret) {
1330 			dev_err(dev->dev, "hbm: add client: failed to send response %d\n",
1331 				ret);
1332 			return -EIO;
1333 		}
1334 		dev_dbg(dev->dev, "hbm: add client request processed\n");
1335 		break;
1336 
1337 	case MEI_HBM_NOTIFY_RES_CMD:
1338 		dev_dbg(dev->dev, "hbm: notify response received\n");
1339 		mei_hbm_cl_res(dev, cl_cmd, notify_res_to_fop(cl_cmd));
1340 		break;
1341 
1342 	case MEI_HBM_NOTIFICATION_CMD:
1343 		dev_dbg(dev->dev, "hbm: notification\n");
1344 		mei_hbm_cl_notify(dev, cl_cmd);
1345 		break;
1346 
1347 	default:
1348 		WARN(1, "hbm: wrong command %d\n", mei_msg->hbm_cmd);
1349 		return -EPROTO;
1350 
1351 	}
1352 	return 0;
1353 }
1354 
1355