xref: /openbmc/linux/drivers/misc/mei/hbm.c (revision c67e8ec0)
1 /*
2  *
3  * Intel Management Engine Interface (Intel MEI) Linux driver
4  * Copyright (c) 2003-2012, Intel Corporation.
5  *
6  * This program is free software; you can redistribute it and/or modify it
7  * under the terms and conditions of the GNU General Public License,
8  * version 2, as published by the Free Software Foundation.
9  *
10  * This program is distributed in the hope it will be useful, but WITHOUT
11  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
12  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
13  * more details.
14  *
15  */
16 
17 #include <linux/export.h>
18 #include <linux/sched.h>
19 #include <linux/wait.h>
20 #include <linux/pm_runtime.h>
21 #include <linux/slab.h>
22 
23 #include <linux/mei.h>
24 
25 #include "mei_dev.h"
26 #include "hbm.h"
27 #include "client.h"
28 
29 static const char *mei_hbm_status_str(enum mei_hbm_status status)
30 {
31 #define MEI_HBM_STATUS(status) case MEI_HBMS_##status: return #status
32 	switch (status) {
33 	MEI_HBM_STATUS(SUCCESS);
34 	MEI_HBM_STATUS(CLIENT_NOT_FOUND);
35 	MEI_HBM_STATUS(ALREADY_EXISTS);
36 	MEI_HBM_STATUS(REJECTED);
37 	MEI_HBM_STATUS(INVALID_PARAMETER);
38 	MEI_HBM_STATUS(NOT_ALLOWED);
39 	MEI_HBM_STATUS(ALREADY_STARTED);
40 	MEI_HBM_STATUS(NOT_STARTED);
41 	default: return "unknown";
42 	}
43 #undef MEI_HBM_STATUS
44 };
45 
46 static const char *mei_cl_conn_status_str(enum mei_cl_connect_status status)
47 {
48 #define MEI_CL_CS(status) case MEI_CL_CONN_##status: return #status
49 	switch (status) {
50 	MEI_CL_CS(SUCCESS);
51 	MEI_CL_CS(NOT_FOUND);
52 	MEI_CL_CS(ALREADY_STARTED);
53 	MEI_CL_CS(OUT_OF_RESOURCES);
54 	MEI_CL_CS(MESSAGE_SMALL);
55 	MEI_CL_CS(NOT_ALLOWED);
56 	default: return "unknown";
57 	}
58 #undef MEI_CL_CCS
59 }
60 
61 const char *mei_hbm_state_str(enum mei_hbm_state state)
62 {
63 #define MEI_HBM_STATE(state) case MEI_HBM_##state: return #state
64 	switch (state) {
65 	MEI_HBM_STATE(IDLE);
66 	MEI_HBM_STATE(STARTING);
67 	MEI_HBM_STATE(STARTED);
68 	MEI_HBM_STATE(DR_SETUP);
69 	MEI_HBM_STATE(ENUM_CLIENTS);
70 	MEI_HBM_STATE(CLIENT_PROPERTIES);
71 	MEI_HBM_STATE(STOPPED);
72 	default:
73 		return "unknown";
74 	}
75 #undef MEI_HBM_STATE
76 }
77 
78 /**
79  * mei_cl_conn_status_to_errno - convert client connect response
80  * status to error code
81  *
82  * @status: client connect response status
83  *
84  * Return: corresponding error code
85  */
86 static int mei_cl_conn_status_to_errno(enum mei_cl_connect_status status)
87 {
88 	switch (status) {
89 	case MEI_CL_CONN_SUCCESS:          return 0;
90 	case MEI_CL_CONN_NOT_FOUND:        return -ENOTTY;
91 	case MEI_CL_CONN_ALREADY_STARTED:  return -EBUSY;
92 	case MEI_CL_CONN_OUT_OF_RESOURCES: return -EBUSY;
93 	case MEI_CL_CONN_MESSAGE_SMALL:    return -EINVAL;
94 	case MEI_CL_CONN_NOT_ALLOWED:      return -EBUSY;
95 	default:                           return -EINVAL;
96 	}
97 }
98 
99 /**
100  * mei_hbm_write_message - wrapper for sending hbm messages.
101  *
102  * @dev: mei device
103  * @hdr: mei header
104  * @data: payload
105  */
106 static inline int mei_hbm_write_message(struct mei_device *dev,
107 					struct mei_msg_hdr *hdr,
108 					const void *data)
109 {
110 	return mei_write_message(dev, hdr, sizeof(*hdr), data, hdr->length);
111 }
112 
113 /**
114  * mei_hbm_idle - set hbm to idle state
115  *
116  * @dev: the device structure
117  */
118 void mei_hbm_idle(struct mei_device *dev)
119 {
120 	dev->init_clients_timer = 0;
121 	dev->hbm_state = MEI_HBM_IDLE;
122 }
123 
124 /**
125  * mei_hbm_reset - reset hbm counters and book keeping data structurs
126  *
127  * @dev: the device structure
128  */
129 void mei_hbm_reset(struct mei_device *dev)
130 {
131 	mei_me_cl_rm_all(dev);
132 
133 	mei_hbm_idle(dev);
134 }
135 
136 /**
137  * mei_hbm_hdr - construct hbm header
138  *
139  * @hdr: hbm header
140  * @length: payload length
141  */
142 
143 static inline void mei_hbm_hdr(struct mei_msg_hdr *hdr, size_t length)
144 {
145 	hdr->host_addr = 0;
146 	hdr->me_addr = 0;
147 	hdr->length = length;
148 	hdr->msg_complete = 1;
149 	hdr->dma_ring = 0;
150 	hdr->reserved = 0;
151 	hdr->internal = 0;
152 }
153 
154 /**
155  * mei_hbm_cl_hdr - construct client hbm header
156  *
157  * @cl: client
158  * @hbm_cmd: host bus message command
159  * @buf: buffer for cl header
160  * @len: buffer length
161  */
162 static inline
163 void mei_hbm_cl_hdr(struct mei_cl *cl, u8 hbm_cmd, void *buf, size_t len)
164 {
165 	struct mei_hbm_cl_cmd *cmd = buf;
166 
167 	memset(cmd, 0, len);
168 
169 	cmd->hbm_cmd = hbm_cmd;
170 	cmd->host_addr = mei_cl_host_addr(cl);
171 	cmd->me_addr = mei_cl_me_id(cl);
172 }
173 
174 /**
175  * mei_hbm_cl_write - write simple hbm client message
176  *
177  * @dev: the device structure
178  * @cl: client
179  * @hbm_cmd: host bus message command
180  * @buf: message buffer
181  * @len: buffer length
182  *
183  * Return: 0 on success, <0 on failure.
184  */
185 static inline int mei_hbm_cl_write(struct mei_device *dev, struct mei_cl *cl,
186 				   u8 hbm_cmd, void *buf, size_t len)
187 {
188 	struct mei_msg_hdr mei_hdr;
189 
190 	mei_hbm_hdr(&mei_hdr, len);
191 	mei_hbm_cl_hdr(cl, hbm_cmd, buf, len);
192 
193 	return mei_hbm_write_message(dev, &mei_hdr, buf);
194 }
195 
196 /**
197  * mei_hbm_cl_addr_equal - check if the client's and
198  *	the message address match
199  *
200  * @cl: client
201  * @cmd: hbm client message
202  *
203  * Return: true if addresses are the same
204  */
205 static inline
206 bool mei_hbm_cl_addr_equal(struct mei_cl *cl, struct mei_hbm_cl_cmd *cmd)
207 {
208 	return  mei_cl_host_addr(cl) == cmd->host_addr &&
209 		mei_cl_me_id(cl) == cmd->me_addr;
210 }
211 
212 /**
213  * mei_hbm_cl_find_by_cmd - find recipient client
214  *
215  * @dev: the device structure
216  * @buf: a buffer with hbm cl command
217  *
218  * Return: the recipient client or NULL if not found
219  */
220 static inline
221 struct mei_cl *mei_hbm_cl_find_by_cmd(struct mei_device *dev, void *buf)
222 {
223 	struct mei_hbm_cl_cmd *cmd = (struct mei_hbm_cl_cmd *)buf;
224 	struct mei_cl *cl;
225 
226 	list_for_each_entry(cl, &dev->file_list, link)
227 		if (mei_hbm_cl_addr_equal(cl, cmd))
228 			return cl;
229 	return NULL;
230 }
231 
232 
233 /**
234  * mei_hbm_start_wait - wait for start response message.
235  *
236  * @dev: the device structure
237  *
238  * Return: 0 on success and < 0 on failure
239  */
240 int mei_hbm_start_wait(struct mei_device *dev)
241 {
242 	int ret;
243 
244 	if (dev->hbm_state > MEI_HBM_STARTING)
245 		return 0;
246 
247 	mutex_unlock(&dev->device_lock);
248 	ret = wait_event_timeout(dev->wait_hbm_start,
249 			dev->hbm_state != MEI_HBM_STARTING,
250 			mei_secs_to_jiffies(MEI_HBM_TIMEOUT));
251 	mutex_lock(&dev->device_lock);
252 
253 	if (ret == 0 && (dev->hbm_state <= MEI_HBM_STARTING)) {
254 		dev->hbm_state = MEI_HBM_IDLE;
255 		dev_err(dev->dev, "waiting for mei start failed\n");
256 		return -ETIME;
257 	}
258 	return 0;
259 }
260 
261 /**
262  * mei_hbm_start_req - sends start request message.
263  *
264  * @dev: the device structure
265  *
266  * Return: 0 on success and < 0 on failure
267  */
268 int mei_hbm_start_req(struct mei_device *dev)
269 {
270 	struct mei_msg_hdr mei_hdr;
271 	struct hbm_host_version_request start_req;
272 	const size_t len = sizeof(struct hbm_host_version_request);
273 	int ret;
274 
275 	mei_hbm_reset(dev);
276 
277 	mei_hbm_hdr(&mei_hdr, len);
278 
279 	/* host start message */
280 	memset(&start_req, 0, len);
281 	start_req.hbm_cmd = HOST_START_REQ_CMD;
282 	start_req.host_version.major_version = HBM_MAJOR_VERSION;
283 	start_req.host_version.minor_version = HBM_MINOR_VERSION;
284 
285 	dev->hbm_state = MEI_HBM_IDLE;
286 	ret = mei_hbm_write_message(dev, &mei_hdr, &start_req);
287 	if (ret) {
288 		dev_err(dev->dev, "version message write failed: ret = %d\n",
289 			ret);
290 		return ret;
291 	}
292 
293 	dev->hbm_state = MEI_HBM_STARTING;
294 	dev->init_clients_timer = MEI_CLIENTS_INIT_TIMEOUT;
295 	mei_schedule_stall_timer(dev);
296 	return 0;
297 }
298 
299 /**
300  * mei_hbm_dma_setup_req() - setup DMA request
301  * @dev: the device structure
302  *
303  * Return: 0 on success and < 0 on failure
304  */
305 static int mei_hbm_dma_setup_req(struct mei_device *dev)
306 {
307 	struct mei_msg_hdr mei_hdr;
308 	struct hbm_dma_setup_request req;
309 	const size_t len = sizeof(struct hbm_dma_setup_request);
310 	unsigned int i;
311 	int ret;
312 
313 	mei_hbm_hdr(&mei_hdr, len);
314 
315 	memset(&req, 0, len);
316 	req.hbm_cmd = MEI_HBM_DMA_SETUP_REQ_CMD;
317 	for (i = 0; i < DMA_DSCR_NUM; i++) {
318 		phys_addr_t paddr;
319 
320 		paddr = dev->dr_dscr[i].daddr;
321 		req.dma_dscr[i].addr_hi = upper_32_bits(paddr);
322 		req.dma_dscr[i].addr_lo = lower_32_bits(paddr);
323 		req.dma_dscr[i].size = dev->dr_dscr[i].size;
324 	}
325 
326 	mei_dma_ring_reset(dev);
327 
328 	ret = mei_hbm_write_message(dev, &mei_hdr, &req);
329 	if (ret) {
330 		dev_err(dev->dev, "dma setup request write failed: ret = %d.\n",
331 			ret);
332 		return ret;
333 	}
334 
335 	dev->hbm_state = MEI_HBM_DR_SETUP;
336 	dev->init_clients_timer = MEI_CLIENTS_INIT_TIMEOUT;
337 	mei_schedule_stall_timer(dev);
338 	return 0;
339 }
340 
341 /**
342  * mei_hbm_enum_clients_req - sends enumeration client request message.
343  *
344  * @dev: the device structure
345  *
346  * Return: 0 on success and < 0 on failure
347  */
348 static int mei_hbm_enum_clients_req(struct mei_device *dev)
349 {
350 	struct mei_msg_hdr mei_hdr;
351 	struct hbm_host_enum_request enum_req;
352 	const size_t len = sizeof(struct hbm_host_enum_request);
353 	int ret;
354 
355 	/* enumerate clients */
356 	mei_hbm_hdr(&mei_hdr, len);
357 
358 	memset(&enum_req, 0, len);
359 	enum_req.hbm_cmd = HOST_ENUM_REQ_CMD;
360 	enum_req.flags |= dev->hbm_f_dc_supported ?
361 			  MEI_HBM_ENUM_F_ALLOW_ADD : 0;
362 	enum_req.flags |= dev->hbm_f_ie_supported ?
363 			  MEI_HBM_ENUM_F_IMMEDIATE_ENUM : 0;
364 
365 	ret = mei_hbm_write_message(dev, &mei_hdr, &enum_req);
366 	if (ret) {
367 		dev_err(dev->dev, "enumeration request write failed: ret = %d.\n",
368 			ret);
369 		return ret;
370 	}
371 	dev->hbm_state = MEI_HBM_ENUM_CLIENTS;
372 	dev->init_clients_timer = MEI_CLIENTS_INIT_TIMEOUT;
373 	mei_schedule_stall_timer(dev);
374 	return 0;
375 }
376 
377 /**
378  * mei_hbm_me_cl_add - add new me client to the list
379  *
380  * @dev: the device structure
381  * @res: hbm property response
382  *
383  * Return: 0 on success and -ENOMEM on allocation failure
384  */
385 
386 static int mei_hbm_me_cl_add(struct mei_device *dev,
387 			     struct hbm_props_response *res)
388 {
389 	struct mei_me_client *me_cl;
390 	const uuid_le *uuid = &res->client_properties.protocol_name;
391 
392 	mei_me_cl_rm_by_uuid(dev, uuid);
393 
394 	me_cl = kzalloc(sizeof(struct mei_me_client), GFP_KERNEL);
395 	if (!me_cl)
396 		return -ENOMEM;
397 
398 	mei_me_cl_init(me_cl);
399 
400 	me_cl->props = res->client_properties;
401 	me_cl->client_id = res->me_addr;
402 	me_cl->tx_flow_ctrl_creds = 0;
403 
404 	mei_me_cl_add(dev, me_cl);
405 
406 	return 0;
407 }
408 
409 /**
410  * mei_hbm_add_cl_resp - send response to fw on client add request
411  *
412  * @dev: the device structure
413  * @addr: me address
414  * @status: response status
415  *
416  * Return: 0 on success and < 0 on failure
417  */
418 static int mei_hbm_add_cl_resp(struct mei_device *dev, u8 addr, u8 status)
419 {
420 	struct mei_msg_hdr mei_hdr;
421 	struct hbm_add_client_response resp;
422 	const size_t len = sizeof(struct hbm_add_client_response);
423 	int ret;
424 
425 	dev_dbg(dev->dev, "adding client response\n");
426 
427 	mei_hbm_hdr(&mei_hdr, len);
428 
429 	memset(&resp, 0, sizeof(struct hbm_add_client_response));
430 	resp.hbm_cmd = MEI_HBM_ADD_CLIENT_RES_CMD;
431 	resp.me_addr = addr;
432 	resp.status  = status;
433 
434 	ret = mei_hbm_write_message(dev, &mei_hdr, &resp);
435 	if (ret)
436 		dev_err(dev->dev, "add client response write failed: ret = %d\n",
437 			ret);
438 	return ret;
439 }
440 
441 /**
442  * mei_hbm_fw_add_cl_req - request from the fw to add a client
443  *
444  * @dev: the device structure
445  * @req: add client request
446  *
447  * Return: 0 on success and < 0 on failure
448  */
449 static int mei_hbm_fw_add_cl_req(struct mei_device *dev,
450 			      struct hbm_add_client_request *req)
451 {
452 	int ret;
453 	u8 status = MEI_HBMS_SUCCESS;
454 
455 	BUILD_BUG_ON(sizeof(struct hbm_add_client_request) !=
456 			sizeof(struct hbm_props_response));
457 
458 	ret = mei_hbm_me_cl_add(dev, (struct hbm_props_response *)req);
459 	if (ret)
460 		status = !MEI_HBMS_SUCCESS;
461 
462 	if (dev->dev_state == MEI_DEV_ENABLED)
463 		schedule_work(&dev->bus_rescan_work);
464 
465 	return mei_hbm_add_cl_resp(dev, req->me_addr, status);
466 }
467 
468 /**
469  * mei_hbm_cl_notify_req - send notification request
470  *
471  * @dev: the device structure
472  * @cl: a client to disconnect from
473  * @start: true for start false for stop
474  *
475  * Return: 0 on success and -EIO on write failure
476  */
477 int mei_hbm_cl_notify_req(struct mei_device *dev,
478 			  struct mei_cl *cl, u8 start)
479 {
480 
481 	struct mei_msg_hdr mei_hdr;
482 	struct hbm_notification_request req;
483 	const size_t len = sizeof(struct hbm_notification_request);
484 	int ret;
485 
486 	mei_hbm_hdr(&mei_hdr, len);
487 	mei_hbm_cl_hdr(cl, MEI_HBM_NOTIFY_REQ_CMD, &req, len);
488 
489 	req.start = start;
490 
491 	ret = mei_hbm_write_message(dev, &mei_hdr, &req);
492 	if (ret)
493 		dev_err(dev->dev, "notify request failed: ret = %d\n", ret);
494 
495 	return ret;
496 }
497 
498 /**
499  *  notify_res_to_fop - convert notification response to the proper
500  *      notification FOP
501  *
502  * @cmd: client notification start response command
503  *
504  * Return:  MEI_FOP_NOTIFY_START or MEI_FOP_NOTIFY_STOP;
505  */
506 static inline enum mei_cb_file_ops notify_res_to_fop(struct mei_hbm_cl_cmd *cmd)
507 {
508 	struct hbm_notification_response *rs =
509 		(struct hbm_notification_response *)cmd;
510 
511 	return mei_cl_notify_req2fop(rs->start);
512 }
513 
514 /**
515  * mei_hbm_cl_notify_start_res - update the client state according
516  *       notify start response
517  *
518  * @dev: the device structure
519  * @cl: mei host client
520  * @cmd: client notification start response command
521  */
522 static void mei_hbm_cl_notify_start_res(struct mei_device *dev,
523 					struct mei_cl *cl,
524 					struct mei_hbm_cl_cmd *cmd)
525 {
526 	struct hbm_notification_response *rs =
527 		(struct hbm_notification_response *)cmd;
528 
529 	cl_dbg(dev, cl, "hbm: notify start response status=%d\n", rs->status);
530 
531 	if (rs->status == MEI_HBMS_SUCCESS ||
532 	    rs->status == MEI_HBMS_ALREADY_STARTED) {
533 		cl->notify_en = true;
534 		cl->status = 0;
535 	} else {
536 		cl->status = -EINVAL;
537 	}
538 }
539 
540 /**
541  * mei_hbm_cl_notify_stop_res - update the client state according
542  *       notify stop response
543  *
544  * @dev: the device structure
545  * @cl: mei host client
546  * @cmd: client notification stop response command
547  */
548 static void mei_hbm_cl_notify_stop_res(struct mei_device *dev,
549 				       struct mei_cl *cl,
550 				       struct mei_hbm_cl_cmd *cmd)
551 {
552 	struct hbm_notification_response *rs =
553 		(struct hbm_notification_response *)cmd;
554 
555 	cl_dbg(dev, cl, "hbm: notify stop response status=%d\n", rs->status);
556 
557 	if (rs->status == MEI_HBMS_SUCCESS ||
558 	    rs->status == MEI_HBMS_NOT_STARTED) {
559 		cl->notify_en = false;
560 		cl->status = 0;
561 	} else {
562 		/* TODO: spec is not clear yet about other possible issues */
563 		cl->status = -EINVAL;
564 	}
565 }
566 
567 /**
568  * mei_hbm_cl_notify - signal notification event
569  *
570  * @dev: the device structure
571  * @cmd: notification client message
572  */
573 static void mei_hbm_cl_notify(struct mei_device *dev,
574 			      struct mei_hbm_cl_cmd *cmd)
575 {
576 	struct mei_cl *cl;
577 
578 	cl = mei_hbm_cl_find_by_cmd(dev, cmd);
579 	if (cl)
580 		mei_cl_notify(cl);
581 }
582 
583 /**
584  * mei_hbm_prop_req - request property for a single client
585  *
586  * @dev: the device structure
587  * @start_idx: client index to start search
588  *
589  * Return: 0 on success and < 0 on failure
590  */
591 static int mei_hbm_prop_req(struct mei_device *dev, unsigned long start_idx)
592 {
593 	struct mei_msg_hdr mei_hdr;
594 	struct hbm_props_request prop_req;
595 	const size_t len = sizeof(struct hbm_props_request);
596 	unsigned long addr;
597 	int ret;
598 
599 	addr = find_next_bit(dev->me_clients_map, MEI_CLIENTS_MAX, start_idx);
600 
601 	/* We got all client properties */
602 	if (addr == MEI_CLIENTS_MAX) {
603 		dev->hbm_state = MEI_HBM_STARTED;
604 		mei_host_client_init(dev);
605 
606 		return 0;
607 	}
608 
609 	mei_hbm_hdr(&mei_hdr, len);
610 
611 	memset(&prop_req, 0, sizeof(struct hbm_props_request));
612 
613 	prop_req.hbm_cmd = HOST_CLIENT_PROPERTIES_REQ_CMD;
614 	prop_req.me_addr = addr;
615 
616 	ret = mei_hbm_write_message(dev, &mei_hdr, &prop_req);
617 	if (ret) {
618 		dev_err(dev->dev, "properties request write failed: ret = %d\n",
619 			ret);
620 		return ret;
621 	}
622 
623 	dev->init_clients_timer = MEI_CLIENTS_INIT_TIMEOUT;
624 	mei_schedule_stall_timer(dev);
625 
626 	return 0;
627 }
628 
629 /**
630  * mei_hbm_pg - sends pg command
631  *
632  * @dev: the device structure
633  * @pg_cmd: the pg command code
634  *
635  * Return: -EIO on write failure
636  *         -EOPNOTSUPP if the operation is not supported by the protocol
637  */
638 int mei_hbm_pg(struct mei_device *dev, u8 pg_cmd)
639 {
640 	struct mei_msg_hdr mei_hdr;
641 	struct hbm_power_gate req;
642 	const size_t len = sizeof(struct hbm_power_gate);
643 	int ret;
644 
645 	if (!dev->hbm_f_pg_supported)
646 		return -EOPNOTSUPP;
647 
648 	mei_hbm_hdr(&mei_hdr, len);
649 
650 	memset(&req, 0, len);
651 	req.hbm_cmd = pg_cmd;
652 
653 	ret = mei_hbm_write_message(dev, &mei_hdr, &req);
654 	if (ret)
655 		dev_err(dev->dev, "power gate command write failed.\n");
656 	return ret;
657 }
658 EXPORT_SYMBOL_GPL(mei_hbm_pg);
659 
660 /**
661  * mei_hbm_stop_req - send stop request message
662  *
663  * @dev: mei device
664  *
665  * Return: -EIO on write failure
666  */
667 static int mei_hbm_stop_req(struct mei_device *dev)
668 {
669 	struct mei_msg_hdr mei_hdr;
670 	struct hbm_host_stop_request req;
671 	const size_t len = sizeof(struct hbm_host_stop_request);
672 
673 	mei_hbm_hdr(&mei_hdr, len);
674 
675 	memset(&req, 0, len);
676 	req.hbm_cmd = HOST_STOP_REQ_CMD;
677 	req.reason = DRIVER_STOP_REQUEST;
678 
679 	return mei_hbm_write_message(dev, &mei_hdr, &req);
680 }
681 
682 /**
683  * mei_hbm_cl_flow_control_req - sends flow control request.
684  *
685  * @dev: the device structure
686  * @cl: client info
687  *
688  * Return: -EIO on write failure
689  */
690 int mei_hbm_cl_flow_control_req(struct mei_device *dev, struct mei_cl *cl)
691 {
692 	struct hbm_flow_control req;
693 
694 	cl_dbg(dev, cl, "sending flow control\n");
695 	return mei_hbm_cl_write(dev, cl, MEI_FLOW_CONTROL_CMD,
696 				&req, sizeof(req));
697 }
698 
699 /**
700  * mei_hbm_add_single_tx_flow_ctrl_creds - adds single buffer credentials.
701  *
702  * @dev: the device structure
703  * @fctrl: flow control response bus message
704  *
705  * Return: 0 on success, < 0 otherwise
706  */
707 static int mei_hbm_add_single_tx_flow_ctrl_creds(struct mei_device *dev,
708 						 struct hbm_flow_control *fctrl)
709 {
710 	struct mei_me_client *me_cl;
711 	int rets;
712 
713 	me_cl = mei_me_cl_by_id(dev, fctrl->me_addr);
714 	if (!me_cl) {
715 		dev_err(dev->dev, "no such me client %d\n", fctrl->me_addr);
716 		return -ENOENT;
717 	}
718 
719 	if (WARN_ON(me_cl->props.single_recv_buf == 0)) {
720 		rets = -EINVAL;
721 		goto out;
722 	}
723 
724 	me_cl->tx_flow_ctrl_creds++;
725 	dev_dbg(dev->dev, "recv flow ctrl msg ME %d (single) creds = %d.\n",
726 		fctrl->me_addr, me_cl->tx_flow_ctrl_creds);
727 
728 	rets = 0;
729 out:
730 	mei_me_cl_put(me_cl);
731 	return rets;
732 }
733 
734 /**
735  * mei_hbm_cl_flow_control_res - flow control response from me
736  *
737  * @dev: the device structure
738  * @fctrl: flow control response bus message
739  */
740 static void mei_hbm_cl_tx_flow_ctrl_creds_res(struct mei_device *dev,
741 					       struct hbm_flow_control *fctrl)
742 {
743 	struct mei_cl *cl;
744 
745 	if (!fctrl->host_addr) {
746 		/* single receive buffer */
747 		mei_hbm_add_single_tx_flow_ctrl_creds(dev, fctrl);
748 		return;
749 	}
750 
751 	cl = mei_hbm_cl_find_by_cmd(dev, fctrl);
752 	if (cl) {
753 		cl->tx_flow_ctrl_creds++;
754 		cl_dbg(dev, cl, "flow control creds = %d.\n",
755 				cl->tx_flow_ctrl_creds);
756 	}
757 }
758 
759 
760 /**
761  * mei_hbm_cl_disconnect_req - sends disconnect message to fw.
762  *
763  * @dev: the device structure
764  * @cl: a client to disconnect from
765  *
766  * Return: -EIO on write failure
767  */
768 int mei_hbm_cl_disconnect_req(struct mei_device *dev, struct mei_cl *cl)
769 {
770 	struct hbm_client_connect_request req;
771 
772 	return mei_hbm_cl_write(dev, cl, CLIENT_DISCONNECT_REQ_CMD,
773 				&req, sizeof(req));
774 }
775 
776 /**
777  * mei_hbm_cl_disconnect_rsp - sends disconnect respose to the FW
778  *
779  * @dev: the device structure
780  * @cl: a client to disconnect from
781  *
782  * Return: -EIO on write failure
783  */
784 int mei_hbm_cl_disconnect_rsp(struct mei_device *dev, struct mei_cl *cl)
785 {
786 	struct hbm_client_connect_response resp;
787 
788 	return mei_hbm_cl_write(dev, cl, CLIENT_DISCONNECT_RES_CMD,
789 				&resp, sizeof(resp));
790 }
791 
792 /**
793  * mei_hbm_cl_disconnect_res - update the client state according
794  *       disconnect response
795  *
796  * @dev: the device structure
797  * @cl: mei host client
798  * @cmd: disconnect client response host bus message
799  */
800 static void mei_hbm_cl_disconnect_res(struct mei_device *dev, struct mei_cl *cl,
801 				      struct mei_hbm_cl_cmd *cmd)
802 {
803 	struct hbm_client_connect_response *rs =
804 		(struct hbm_client_connect_response *)cmd;
805 
806 	cl_dbg(dev, cl, "hbm: disconnect response status=%d\n", rs->status);
807 
808 	if (rs->status == MEI_CL_DISCONN_SUCCESS)
809 		cl->state = MEI_FILE_DISCONNECT_REPLY;
810 	cl->status = 0;
811 }
812 
813 /**
814  * mei_hbm_cl_connect_req - send connection request to specific me client
815  *
816  * @dev: the device structure
817  * @cl: a client to connect to
818  *
819  * Return: -EIO on write failure
820  */
821 int mei_hbm_cl_connect_req(struct mei_device *dev, struct mei_cl *cl)
822 {
823 	struct hbm_client_connect_request req;
824 
825 	return mei_hbm_cl_write(dev, cl, CLIENT_CONNECT_REQ_CMD,
826 				&req, sizeof(req));
827 }
828 
829 /**
830  * mei_hbm_cl_connect_res - update the client state according
831  *        connection response
832  *
833  * @dev: the device structure
834  * @cl: mei host client
835  * @cmd: connect client response host bus message
836  */
837 static void mei_hbm_cl_connect_res(struct mei_device *dev, struct mei_cl *cl,
838 				   struct mei_hbm_cl_cmd *cmd)
839 {
840 	struct hbm_client_connect_response *rs =
841 		(struct hbm_client_connect_response *)cmd;
842 
843 	cl_dbg(dev, cl, "hbm: connect response status=%s\n",
844 			mei_cl_conn_status_str(rs->status));
845 
846 	if (rs->status == MEI_CL_CONN_SUCCESS)
847 		cl->state = MEI_FILE_CONNECTED;
848 	else {
849 		cl->state = MEI_FILE_DISCONNECT_REPLY;
850 		if (rs->status == MEI_CL_CONN_NOT_FOUND) {
851 			mei_me_cl_del(dev, cl->me_cl);
852 			if (dev->dev_state == MEI_DEV_ENABLED)
853 				schedule_work(&dev->bus_rescan_work);
854 		}
855 	}
856 	cl->status = mei_cl_conn_status_to_errno(rs->status);
857 }
858 
859 /**
860  * mei_hbm_cl_res - process hbm response received on behalf
861  *         an client
862  *
863  * @dev: the device structure
864  * @rs:  hbm client message
865  * @fop_type: file operation type
866  */
867 static void mei_hbm_cl_res(struct mei_device *dev,
868 			   struct mei_hbm_cl_cmd *rs,
869 			   enum mei_cb_file_ops fop_type)
870 {
871 	struct mei_cl *cl;
872 	struct mei_cl_cb *cb, *next;
873 
874 	cl = NULL;
875 	list_for_each_entry_safe(cb, next, &dev->ctrl_rd_list, list) {
876 
877 		cl = cb->cl;
878 
879 		if (cb->fop_type != fop_type)
880 			continue;
881 
882 		if (mei_hbm_cl_addr_equal(cl, rs)) {
883 			list_del_init(&cb->list);
884 			break;
885 		}
886 	}
887 
888 	if (!cl)
889 		return;
890 
891 	switch (fop_type) {
892 	case MEI_FOP_CONNECT:
893 		mei_hbm_cl_connect_res(dev, cl, rs);
894 		break;
895 	case MEI_FOP_DISCONNECT:
896 		mei_hbm_cl_disconnect_res(dev, cl, rs);
897 		break;
898 	case MEI_FOP_NOTIFY_START:
899 		mei_hbm_cl_notify_start_res(dev, cl, rs);
900 		break;
901 	case MEI_FOP_NOTIFY_STOP:
902 		mei_hbm_cl_notify_stop_res(dev, cl, rs);
903 		break;
904 	default:
905 		return;
906 	}
907 
908 	cl->timer_count = 0;
909 	wake_up(&cl->wait);
910 }
911 
912 
913 /**
914  * mei_hbm_fw_disconnect_req - disconnect request initiated by ME firmware
915  *  host sends disconnect response
916  *
917  * @dev: the device structure.
918  * @disconnect_req: disconnect request bus message from the me
919  *
920  * Return: -ENOMEM on allocation failure
921  */
922 static int mei_hbm_fw_disconnect_req(struct mei_device *dev,
923 		struct hbm_client_connect_request *disconnect_req)
924 {
925 	struct mei_cl *cl;
926 	struct mei_cl_cb *cb;
927 
928 	cl = mei_hbm_cl_find_by_cmd(dev, disconnect_req);
929 	if (cl) {
930 		cl_warn(dev, cl, "fw disconnect request received\n");
931 		cl->state = MEI_FILE_DISCONNECTING;
932 		cl->timer_count = 0;
933 
934 		cb = mei_cl_enqueue_ctrl_wr_cb(cl, 0, MEI_FOP_DISCONNECT_RSP,
935 					       NULL);
936 		if (!cb)
937 			return -ENOMEM;
938 	}
939 	return 0;
940 }
941 
942 /**
943  * mei_hbm_pg_enter_res - PG enter response received
944  *
945  * @dev: the device structure.
946  *
947  * Return: 0 on success, -EPROTO on state mismatch
948  */
949 static int mei_hbm_pg_enter_res(struct mei_device *dev)
950 {
951 	if (mei_pg_state(dev) != MEI_PG_OFF ||
952 	    dev->pg_event != MEI_PG_EVENT_WAIT) {
953 		dev_err(dev->dev, "hbm: pg entry response: state mismatch [%s, %d]\n",
954 			mei_pg_state_str(mei_pg_state(dev)), dev->pg_event);
955 		return -EPROTO;
956 	}
957 
958 	dev->pg_event = MEI_PG_EVENT_RECEIVED;
959 	wake_up(&dev->wait_pg);
960 
961 	return 0;
962 }
963 
964 /**
965  * mei_hbm_pg_resume - process with PG resume
966  *
967  * @dev: the device structure.
968  */
969 void mei_hbm_pg_resume(struct mei_device *dev)
970 {
971 	pm_request_resume(dev->dev);
972 }
973 EXPORT_SYMBOL_GPL(mei_hbm_pg_resume);
974 
975 /**
976  * mei_hbm_pg_exit_res - PG exit response received
977  *
978  * @dev: the device structure.
979  *
980  * Return: 0 on success, -EPROTO on state mismatch
981  */
982 static int mei_hbm_pg_exit_res(struct mei_device *dev)
983 {
984 	if (mei_pg_state(dev) != MEI_PG_ON ||
985 	    (dev->pg_event != MEI_PG_EVENT_WAIT &&
986 	     dev->pg_event != MEI_PG_EVENT_IDLE)) {
987 		dev_err(dev->dev, "hbm: pg exit response: state mismatch [%s, %d]\n",
988 			mei_pg_state_str(mei_pg_state(dev)), dev->pg_event);
989 		return -EPROTO;
990 	}
991 
992 	switch (dev->pg_event) {
993 	case MEI_PG_EVENT_WAIT:
994 		dev->pg_event = MEI_PG_EVENT_RECEIVED;
995 		wake_up(&dev->wait_pg);
996 		break;
997 	case MEI_PG_EVENT_IDLE:
998 		/*
999 		* If the driver is not waiting on this then
1000 		* this is HW initiated exit from PG.
1001 		* Start runtime pm resume sequence to exit from PG.
1002 		*/
1003 		dev->pg_event = MEI_PG_EVENT_RECEIVED;
1004 		mei_hbm_pg_resume(dev);
1005 		break;
1006 	default:
1007 		WARN(1, "hbm: pg exit response: unexpected pg event = %d\n",
1008 		     dev->pg_event);
1009 		return -EPROTO;
1010 	}
1011 
1012 	return 0;
1013 }
1014 
1015 /**
1016  * mei_hbm_config_features - check what hbm features and commands
1017  *        are supported by the fw
1018  *
1019  * @dev: the device structure
1020  */
1021 static void mei_hbm_config_features(struct mei_device *dev)
1022 {
1023 	/* Power Gating Isolation Support */
1024 	dev->hbm_f_pg_supported = 0;
1025 	if (dev->version.major_version > HBM_MAJOR_VERSION_PGI)
1026 		dev->hbm_f_pg_supported = 1;
1027 
1028 	if (dev->version.major_version == HBM_MAJOR_VERSION_PGI &&
1029 	    dev->version.minor_version >= HBM_MINOR_VERSION_PGI)
1030 		dev->hbm_f_pg_supported = 1;
1031 
1032 	if (dev->version.major_version >= HBM_MAJOR_VERSION_DC)
1033 		dev->hbm_f_dc_supported = 1;
1034 
1035 	if (dev->version.major_version >= HBM_MAJOR_VERSION_IE)
1036 		dev->hbm_f_ie_supported = 1;
1037 
1038 	/* disconnect on connect timeout instead of link reset */
1039 	if (dev->version.major_version >= HBM_MAJOR_VERSION_DOT)
1040 		dev->hbm_f_dot_supported = 1;
1041 
1042 	/* Notification Event Support */
1043 	if (dev->version.major_version >= HBM_MAJOR_VERSION_EV)
1044 		dev->hbm_f_ev_supported = 1;
1045 
1046 	/* Fixed Address Client Support */
1047 	if (dev->version.major_version >= HBM_MAJOR_VERSION_FA)
1048 		dev->hbm_f_fa_supported = 1;
1049 
1050 	/* OS ver message Support */
1051 	if (dev->version.major_version >= HBM_MAJOR_VERSION_OS)
1052 		dev->hbm_f_os_supported = 1;
1053 
1054 	/* DMA Ring Support */
1055 	if (dev->version.major_version > HBM_MAJOR_VERSION_DR ||
1056 	    (dev->version.major_version == HBM_MAJOR_VERSION_DR &&
1057 	     dev->version.minor_version >= HBM_MINOR_VERSION_DR))
1058 		dev->hbm_f_dr_supported = 1;
1059 }
1060 
1061 /**
1062  * mei_hbm_version_is_supported - checks whether the driver can
1063  *     support the hbm version of the device
1064  *
1065  * @dev: the device structure
1066  * Return: true if driver can support hbm version of the device
1067  */
1068 bool mei_hbm_version_is_supported(struct mei_device *dev)
1069 {
1070 	return	(dev->version.major_version < HBM_MAJOR_VERSION) ||
1071 		(dev->version.major_version == HBM_MAJOR_VERSION &&
1072 		 dev->version.minor_version <= HBM_MINOR_VERSION);
1073 }
1074 
1075 /**
1076  * mei_hbm_dispatch - bottom half read routine after ISR to
1077  * handle the read bus message cmd processing.
1078  *
1079  * @dev: the device structure
1080  * @hdr: header of bus message
1081  *
1082  * Return: 0 on success and < 0 on failure
1083  */
1084 int mei_hbm_dispatch(struct mei_device *dev, struct mei_msg_hdr *hdr)
1085 {
1086 	struct mei_bus_message *mei_msg;
1087 	struct hbm_host_version_response *version_res;
1088 	struct hbm_props_response *props_res;
1089 	struct hbm_host_enum_response *enum_res;
1090 	struct hbm_dma_setup_response *dma_setup_res;
1091 	struct hbm_add_client_request *add_cl_req;
1092 	int ret;
1093 
1094 	struct mei_hbm_cl_cmd *cl_cmd;
1095 	struct hbm_client_connect_request *disconnect_req;
1096 	struct hbm_flow_control *fctrl;
1097 
1098 	/* read the message to our buffer */
1099 	BUG_ON(hdr->length >= sizeof(dev->rd_msg_buf));
1100 	mei_read_slots(dev, dev->rd_msg_buf, hdr->length);
1101 	mei_msg = (struct mei_bus_message *)dev->rd_msg_buf;
1102 	cl_cmd  = (struct mei_hbm_cl_cmd *)mei_msg;
1103 
1104 	/* ignore spurious message and prevent reset nesting
1105 	 * hbm is put to idle during system reset
1106 	 */
1107 	if (dev->hbm_state == MEI_HBM_IDLE) {
1108 		dev_dbg(dev->dev, "hbm: state is idle ignore spurious messages\n");
1109 		return 0;
1110 	}
1111 
1112 	switch (mei_msg->hbm_cmd) {
1113 	case HOST_START_RES_CMD:
1114 		dev_dbg(dev->dev, "hbm: start: response message received.\n");
1115 
1116 		dev->init_clients_timer = 0;
1117 
1118 		version_res = (struct hbm_host_version_response *)mei_msg;
1119 
1120 		dev_dbg(dev->dev, "HBM VERSION: DRIVER=%02d:%02d DEVICE=%02d:%02d\n",
1121 				HBM_MAJOR_VERSION, HBM_MINOR_VERSION,
1122 				version_res->me_max_version.major_version,
1123 				version_res->me_max_version.minor_version);
1124 
1125 		if (version_res->host_version_supported) {
1126 			dev->version.major_version = HBM_MAJOR_VERSION;
1127 			dev->version.minor_version = HBM_MINOR_VERSION;
1128 		} else {
1129 			dev->version.major_version =
1130 				version_res->me_max_version.major_version;
1131 			dev->version.minor_version =
1132 				version_res->me_max_version.minor_version;
1133 		}
1134 
1135 		if (!mei_hbm_version_is_supported(dev)) {
1136 			dev_warn(dev->dev, "hbm: start: version mismatch - stopping the driver.\n");
1137 
1138 			dev->hbm_state = MEI_HBM_STOPPED;
1139 			if (mei_hbm_stop_req(dev)) {
1140 				dev_err(dev->dev, "hbm: start: failed to send stop request\n");
1141 				return -EIO;
1142 			}
1143 			break;
1144 		}
1145 
1146 		mei_hbm_config_features(dev);
1147 
1148 		if (dev->dev_state != MEI_DEV_INIT_CLIENTS ||
1149 		    dev->hbm_state != MEI_HBM_STARTING) {
1150 			dev_err(dev->dev, "hbm: start: state mismatch, [%d, %d]\n",
1151 				dev->dev_state, dev->hbm_state);
1152 			return -EPROTO;
1153 		}
1154 
1155 		if (dev->hbm_f_dr_supported) {
1156 			if (mei_dmam_ring_alloc(dev))
1157 				dev_info(dev->dev, "running w/o dma ring\n");
1158 			if (mei_dma_ring_is_allocated(dev)) {
1159 				if (mei_hbm_dma_setup_req(dev))
1160 					return -EIO;
1161 
1162 				wake_up(&dev->wait_hbm_start);
1163 				break;
1164 			}
1165 		}
1166 
1167 		dev->hbm_f_dr_supported = 0;
1168 		mei_dmam_ring_free(dev);
1169 
1170 		if (mei_hbm_enum_clients_req(dev))
1171 			return -EIO;
1172 
1173 		wake_up(&dev->wait_hbm_start);
1174 		break;
1175 
1176 	case MEI_HBM_DMA_SETUP_RES_CMD:
1177 		dev_dbg(dev->dev, "hbm: dma setup response: message received.\n");
1178 
1179 		dev->init_clients_timer = 0;
1180 
1181 		if (dev->hbm_state != MEI_HBM_DR_SETUP) {
1182 			dev_err(dev->dev, "hbm: dma setup response: state mismatch, [%d, %d]\n",
1183 				dev->dev_state, dev->hbm_state);
1184 			return -EPROTO;
1185 		}
1186 
1187 		dma_setup_res = (struct hbm_dma_setup_response *)mei_msg;
1188 
1189 		if (dma_setup_res->status) {
1190 			dev_info(dev->dev, "hbm: dma setup response: failure = %d %s\n",
1191 				 dma_setup_res->status,
1192 				 mei_hbm_status_str(dma_setup_res->status));
1193 			dev->hbm_f_dr_supported = 0;
1194 			mei_dmam_ring_free(dev);
1195 		}
1196 
1197 		if (mei_hbm_enum_clients_req(dev))
1198 			return -EIO;
1199 		break;
1200 
1201 	case CLIENT_CONNECT_RES_CMD:
1202 		dev_dbg(dev->dev, "hbm: client connect response: message received.\n");
1203 		mei_hbm_cl_res(dev, cl_cmd, MEI_FOP_CONNECT);
1204 		break;
1205 
1206 	case CLIENT_DISCONNECT_RES_CMD:
1207 		dev_dbg(dev->dev, "hbm: client disconnect response: message received.\n");
1208 		mei_hbm_cl_res(dev, cl_cmd, MEI_FOP_DISCONNECT);
1209 		break;
1210 
1211 	case MEI_FLOW_CONTROL_CMD:
1212 		dev_dbg(dev->dev, "hbm: client flow control response: message received.\n");
1213 
1214 		fctrl = (struct hbm_flow_control *)mei_msg;
1215 		mei_hbm_cl_tx_flow_ctrl_creds_res(dev, fctrl);
1216 		break;
1217 
1218 	case MEI_PG_ISOLATION_ENTRY_RES_CMD:
1219 		dev_dbg(dev->dev, "hbm: power gate isolation entry response received\n");
1220 		ret = mei_hbm_pg_enter_res(dev);
1221 		if (ret)
1222 			return ret;
1223 		break;
1224 
1225 	case MEI_PG_ISOLATION_EXIT_REQ_CMD:
1226 		dev_dbg(dev->dev, "hbm: power gate isolation exit request received\n");
1227 		ret = mei_hbm_pg_exit_res(dev);
1228 		if (ret)
1229 			return ret;
1230 		break;
1231 
1232 	case HOST_CLIENT_PROPERTIES_RES_CMD:
1233 		dev_dbg(dev->dev, "hbm: properties response: message received.\n");
1234 
1235 		dev->init_clients_timer = 0;
1236 
1237 		if (dev->dev_state != MEI_DEV_INIT_CLIENTS ||
1238 		    dev->hbm_state != MEI_HBM_CLIENT_PROPERTIES) {
1239 			dev_err(dev->dev, "hbm: properties response: state mismatch, [%d, %d]\n",
1240 				dev->dev_state, dev->hbm_state);
1241 			return -EPROTO;
1242 		}
1243 
1244 		props_res = (struct hbm_props_response *)mei_msg;
1245 
1246 		if (props_res->status == MEI_HBMS_CLIENT_NOT_FOUND) {
1247 			dev_dbg(dev->dev, "hbm: properties response: %d CLIENT_NOT_FOUND\n",
1248 				props_res->me_addr);
1249 		} else if (props_res->status) {
1250 			dev_err(dev->dev, "hbm: properties response: wrong status = %d %s\n",
1251 				props_res->status,
1252 				mei_hbm_status_str(props_res->status));
1253 			return -EPROTO;
1254 		} else {
1255 			mei_hbm_me_cl_add(dev, props_res);
1256 		}
1257 
1258 		/* request property for the next client */
1259 		if (mei_hbm_prop_req(dev, props_res->me_addr + 1))
1260 			return -EIO;
1261 
1262 		break;
1263 
1264 	case HOST_ENUM_RES_CMD:
1265 		dev_dbg(dev->dev, "hbm: enumeration response: message received\n");
1266 
1267 		dev->init_clients_timer = 0;
1268 
1269 		enum_res = (struct hbm_host_enum_response *) mei_msg;
1270 		BUILD_BUG_ON(sizeof(dev->me_clients_map)
1271 				< sizeof(enum_res->valid_addresses));
1272 		memcpy(dev->me_clients_map, enum_res->valid_addresses,
1273 				sizeof(enum_res->valid_addresses));
1274 
1275 		if (dev->dev_state != MEI_DEV_INIT_CLIENTS ||
1276 		    dev->hbm_state != MEI_HBM_ENUM_CLIENTS) {
1277 			dev_err(dev->dev, "hbm: enumeration response: state mismatch, [%d, %d]\n",
1278 				dev->dev_state, dev->hbm_state);
1279 			return -EPROTO;
1280 		}
1281 
1282 		dev->hbm_state = MEI_HBM_CLIENT_PROPERTIES;
1283 
1284 		/* first property request */
1285 		if (mei_hbm_prop_req(dev, 0))
1286 			return -EIO;
1287 
1288 		break;
1289 
1290 	case HOST_STOP_RES_CMD:
1291 		dev_dbg(dev->dev, "hbm: stop response: message received\n");
1292 
1293 		dev->init_clients_timer = 0;
1294 
1295 		if (dev->hbm_state != MEI_HBM_STOPPED) {
1296 			dev_err(dev->dev, "hbm: stop response: state mismatch, [%d, %d]\n",
1297 				dev->dev_state, dev->hbm_state);
1298 			return -EPROTO;
1299 		}
1300 
1301 		dev->dev_state = MEI_DEV_POWER_DOWN;
1302 		dev_info(dev->dev, "hbm: stop response: resetting.\n");
1303 		/* force the reset */
1304 		return -EPROTO;
1305 		break;
1306 
1307 	case CLIENT_DISCONNECT_REQ_CMD:
1308 		dev_dbg(dev->dev, "hbm: disconnect request: message received\n");
1309 
1310 		disconnect_req = (struct hbm_client_connect_request *)mei_msg;
1311 		mei_hbm_fw_disconnect_req(dev, disconnect_req);
1312 		break;
1313 
1314 	case ME_STOP_REQ_CMD:
1315 		dev_dbg(dev->dev, "hbm: stop request: message received\n");
1316 		dev->hbm_state = MEI_HBM_STOPPED;
1317 		if (mei_hbm_stop_req(dev)) {
1318 			dev_err(dev->dev, "hbm: stop request: failed to send stop request\n");
1319 			return -EIO;
1320 		}
1321 		break;
1322 
1323 	case MEI_HBM_ADD_CLIENT_REQ_CMD:
1324 		dev_dbg(dev->dev, "hbm: add client request received\n");
1325 		/*
1326 		 * after the host receives the enum_resp
1327 		 * message clients may be added or removed
1328 		 */
1329 		if (dev->hbm_state <= MEI_HBM_ENUM_CLIENTS ||
1330 		    dev->hbm_state >= MEI_HBM_STOPPED) {
1331 			dev_err(dev->dev, "hbm: add client: state mismatch, [%d, %d]\n",
1332 				dev->dev_state, dev->hbm_state);
1333 			return -EPROTO;
1334 		}
1335 		add_cl_req = (struct hbm_add_client_request *)mei_msg;
1336 		ret = mei_hbm_fw_add_cl_req(dev, add_cl_req);
1337 		if (ret) {
1338 			dev_err(dev->dev, "hbm: add client: failed to send response %d\n",
1339 				ret);
1340 			return -EIO;
1341 		}
1342 		dev_dbg(dev->dev, "hbm: add client request processed\n");
1343 		break;
1344 
1345 	case MEI_HBM_NOTIFY_RES_CMD:
1346 		dev_dbg(dev->dev, "hbm: notify response received\n");
1347 		mei_hbm_cl_res(dev, cl_cmd, notify_res_to_fop(cl_cmd));
1348 		break;
1349 
1350 	case MEI_HBM_NOTIFICATION_CMD:
1351 		dev_dbg(dev->dev, "hbm: notification\n");
1352 		mei_hbm_cl_notify(dev, cl_cmd);
1353 		break;
1354 
1355 	default:
1356 		WARN(1, "hbm: wrong command %d\n", mei_msg->hbm_cmd);
1357 		return -EPROTO;
1358 
1359 	}
1360 	return 0;
1361 }
1362 
1363