summaryrefslogtreecommitdiffstats
path: root/drivers/misc/mei/hbm.c
blob: 239d7f5d6a92a851b48e381e5db05c9e94eb1c0f (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702
703
704
705
706
707
708
709
710
711
712
713
714
715
716
717
718
719
720
721
722
723
724
725
726
727
728
729
730
731
732
733
734
735
736
737
738
739
740
741
742
743
744
745
746
747
748
749
750
751
752
753
754
755
756
757
758
759
760
761
762
763
764
765
766
767
768
769
770
771
772
773
774
775
776
777
778
779
780
781
782
783
784
785
786
787
788
789
790
791
792
793
794
795
796
797
798
799
800
801
802
803
804
805
806
807
808
809
810
811
812
813
814
815
816
817
818
819
820
821
822
823
824
825
826
827
828
829
830
831
832
833
834
835
836
837
838
839
840
841
842
843
844
845
846
847
848
849
850
851
852
853
854
855
856
857
858
859
860
861
862
863
864
865
866
867
868
869
870
871
872
873
874
875
876
877
878
879
880
881
882
883
884
885
886
887
888
889
890
891
892
893
894
895
896
897
898
899
900
901
902
903
904
905
906
907
908
909
910
911
912
913
914
915
916
917
918
919
920
921
922
923
924
925
926
927
928
929
930
931
932
933
934
935
936
937
938
939
940
941
942
943
944
945
946
947
948
949
950
951
/*
 *
 * Intel Management Engine Interface (Intel MEI) Linux driver
 * Copyright (c) 2003-2012, Intel Corporation.
 *
 * This program is free software; you can redistribute it and/or modify it
 * under the terms and conditions of the GNU General Public License,
 * version 2, as published by the Free Software Foundation.
 *
 * This program is distributed in the hope it will be useful, but WITHOUT
 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
 * more details.
 *
 */

#include <linux/export.h>
#include <linux/sched.h>
#include <linux/wait.h>
#include <linux/pm_runtime.h>
#include <linux/slab.h>

#include <linux/mei.h>

#include "mei_dev.h"
#include "hbm.h"
#include "client.h"

static const char *mei_hbm_status_str(enum mei_hbm_status status)
{
#define MEI_HBM_STATUS(status) case MEI_HBMS_##status: return #status
	switch (status) {
	MEI_HBM_STATUS(SUCCESS);
	MEI_HBM_STATUS(CLIENT_NOT_FOUND);
	MEI_HBM_STATUS(ALREADY_EXISTS);
	MEI_HBM_STATUS(REJECTED);
	MEI_HBM_STATUS(INVALID_PARAMETER);
	MEI_HBM_STATUS(NOT_ALLOWED);
	MEI_HBM_STATUS(ALREADY_STARTED);
	MEI_HBM_STATUS(NOT_STARTED);
	default: return "unknown";
	}
#undef MEI_HBM_STATUS
};

static const char *mei_cl_conn_status_str(enum mei_cl_connect_status status)
{
#define MEI_CL_CS(status) case MEI_CL_CONN_##status: return #status
	switch (status) {
	MEI_CL_CS(SUCCESS);
	MEI_CL_CS(NOT_FOUND);
	MEI_CL_CS(ALREADY_STARTED);
	MEI_CL_CS(OUT_OF_RESOURCES);
	MEI_CL_CS(MESSAGE_SMALL);
	default: return "unknown";
	}
#undef MEI_CL_CCS
}

const char *mei_hbm_state_str(enum mei_hbm_state state)
{
#define MEI_HBM_STATE(state) case MEI_HBM_##state: return #state
	switch (state) {
	MEI_HBM_STATE(IDLE);
	MEI_HBM_STATE(STARTING);
	MEI_HBM_STATE(STARTED);
	MEI_HBM_STATE(ENUM_CLIENTS);
	MEI_HBM_STATE(CLIENT_PROPERTIES);
	MEI_HBM_STATE(STOPPED);
	default:
		return "unknown";
	}
#undef MEI_HBM_STATE
}

/**
 * mei_cl_conn_status_to_errno - convert client connect response
 * status to error code
 *
 * @status: client connect response status
 *
 * Return: corresponding error code
 */
static int mei_cl_conn_status_to_errno(enum mei_cl_connect_status status)
{
	switch (status) {
	case MEI_CL_CONN_SUCCESS:          return 0;
	case MEI_CL_CONN_NOT_FOUND:        return -ENOTTY;
	case MEI_CL_CONN_ALREADY_STARTED:  return -EBUSY;
	case MEI_CL_CONN_OUT_OF_RESOURCES: return -EBUSY;
	case MEI_CL_CONN_MESSAGE_SMALL:    return -EINVAL;
	default:                           return -EINVAL;
	}
}

/**
 * mei_hbm_idle - set hbm to idle state
 *
 * @dev: the device structure
 */
void mei_hbm_idle(struct mei_device *dev)
{
	dev->init_clients_timer = 0;
	dev->hbm_state = MEI_HBM_IDLE;
}

/**
 * mei_me_cl_remove_all - remove all me clients
 *
 * @dev: the device structure
 */
static void mei_me_cl_remove_all(struct mei_device *dev)
{
	struct mei_me_client *me_cl, *next;

	list_for_each_entry_safe(me_cl, next, &dev->me_clients, list) {
			list_del(&me_cl->list);
			kfree(me_cl);
	}
}

/**
 * mei_hbm_reset - reset hbm counters and book keeping data structurs
 *
 * @dev: the device structure
 */
void mei_hbm_reset(struct mei_device *dev)
{
	dev->me_client_index = 0;

	mei_me_cl_remove_all(dev);

	mei_hbm_idle(dev);
}

/**
 * mei_hbm_hdr - construct hbm header
 *
 * @hdr: hbm header
 * @length: payload length
 */

static inline void mei_hbm_hdr(struct mei_msg_hdr *hdr, size_t length)
{
	hdr->host_addr = 0;
	hdr->me_addr = 0;
	hdr->length = length;
	hdr->msg_complete = 1;
	hdr->reserved = 0;
}

/**
 * mei_hbm_cl_hdr - construct client hbm header
 *
 * @cl: client
 * @hbm_cmd: host bus message command
 * @buf: buffer for cl header
 * @len: buffer length
 */
static inline
void mei_hbm_cl_hdr(struct mei_cl *cl, u8 hbm_cmd, void *buf, size_t len)
{
	struct mei_hbm_cl_cmd *cmd = buf;

	memset(cmd, 0, len);

	cmd->hbm_cmd = hbm_cmd;
	cmd->host_addr = cl->host_client_id;
	cmd->me_addr = cl->me_client_id;
}

/**
 * mei_hbm_cl_write - write simple hbm client message
 *
 * @dev: the device structure
 * @cl: client
 * @hbm_cmd: host bus message command
 * @len: buffer length
 *
 * Return: 0 on success, <0 on failure.
 */
static inline
int mei_hbm_cl_write(struct mei_device *dev,
		     struct mei_cl *cl, u8 hbm_cmd, size_t len)
{
	struct mei_msg_hdr *mei_hdr = &dev->wr_msg.hdr;

	mei_hbm_hdr(mei_hdr, len);
	mei_hbm_cl_hdr(cl, hbm_cmd, dev->wr_msg.data, len);

	return mei_write_message(dev, mei_hdr, dev->wr_msg.data);
}

/**
 * mei_hbm_cl_addr_equal - check if the client's and
 *	the message address match
 *
 * @cl: client
 * @cmd: hbm client message
 *
 * Return: true if addresses are the same
 */
static inline
bool mei_hbm_cl_addr_equal(struct mei_cl *cl, struct mei_hbm_cl_cmd *cmd)
{
	return cl->host_client_id == cmd->host_addr &&
		cl->me_client_id == cmd->me_addr;
}

/**
 * mei_hbm_cl_find_by_cmd - find recipient client
 *
 * @dev: the device structure
 * @buf: a buffer with hbm cl command
 *
 * Return: the recipient client or NULL if not found
 */
static inline
struct mei_cl *mei_hbm_cl_find_by_cmd(struct mei_device *dev, void *buf)
{
	struct mei_hbm_cl_cmd *cmd = (struct mei_hbm_cl_cmd *)buf;
	struct mei_cl *cl;

	list_for_each_entry(cl, &dev->file_list, link)
		if (mei_hbm_cl_addr_equal(cl, cmd))
			return cl;
	return NULL;
}


/**
 * mei_hbm_start_wait - wait for start response message.
 *
 * @dev: the device structure
 *
 * Return: 0 on success and < 0 on failure
 */
int mei_hbm_start_wait(struct mei_device *dev)
{
	int ret;

	if (dev->hbm_state > MEI_HBM_STARTING)
		return 0;

	mutex_unlock(&dev->device_lock);
	ret = wait_event_timeout(dev->wait_hbm_start,
			dev->hbm_state != MEI_HBM_STARTING,
			mei_secs_to_jiffies(MEI_HBM_TIMEOUT));
	mutex_lock(&dev->device_lock);

	if (ret == 0 && (dev->hbm_state <= MEI_HBM_STARTING)) {
		dev->hbm_state = MEI_HBM_IDLE;
		dev_err(dev->dev, "waiting for mei start failed\n");
		return -ETIME;
	}
	return 0;
}

/**
 * mei_hbm_start_req - sends start request message.
 *
 * @dev: the device structure
 *
 * Return: 0 on success and < 0 on failure
 */
int mei_hbm_start_req(struct mei_device *dev)
{
	struct mei_msg_hdr *mei_hdr = &dev->wr_msg.hdr;
	struct hbm_host_version_request *start_req;
	const size_t len = sizeof(struct hbm_host_version_request);
	int ret;

	mei_hbm_reset(dev);

	mei_hbm_hdr(mei_hdr, len);

	/* host start message */
	start_req = (struct hbm_host_version_request *)dev->wr_msg.data;
	memset(start_req, 0, len);
	start_req->hbm_cmd = HOST_START_REQ_CMD;
	start_req->host_version.major_version = HBM_MAJOR_VERSION;
	start_req->host_version.minor_version = HBM_MINOR_VERSION;

	dev->hbm_state = MEI_HBM_IDLE;
	ret = mei_write_message(dev, mei_hdr, dev->wr_msg.data);
	if (ret) {
		dev_err(dev->dev, "version message write failed: ret = %d\n",
			ret);
		return ret;
	}

	dev->hbm_state = MEI_HBM_STARTING;
	dev->init_clients_timer = MEI_CLIENTS_INIT_TIMEOUT;
	return 0;
}

/*
 * mei_hbm_enum_clients_req - sends enumeration client request message.
 *
 * @dev: the device structure
 *
 * Return: 0 on success and < 0 on failure
 */
static int mei_hbm_enum_clients_req(struct mei_device *dev)
{
	struct mei_msg_hdr *mei_hdr = &dev->wr_msg.hdr;
	struct hbm_host_enum_request *enum_req;
	const size_t len = sizeof(struct hbm_host_enum_request);
	int ret;

	/* enumerate clients */
	mei_hbm_hdr(mei_hdr, len);

	enum_req = (struct hbm_host_enum_request *)dev->wr_msg.data;
	memset(enum_req, 0, len);
	enum_req->hbm_cmd = HOST_ENUM_REQ_CMD;

	ret = mei_write_message(dev, mei_hdr, dev->wr_msg.data);
	if (ret) {
		dev_err(dev->dev, "enumeration request write failed: ret = %d.\n",
			ret);
		return ret;
	}
	dev->hbm_state = MEI_HBM_ENUM_CLIENTS;
	dev->init_clients_timer = MEI_CLIENTS_INIT_TIMEOUT;
	return 0;
}

/*
 * mei_hbm_me_cl_add - add new me client to the list
 *
 * @dev: the device structure
 * @res: hbm property response
 *
 * Return: 0 on success and -ENOMEM on allocation failure
 */

static int mei_hbm_me_cl_add(struct mei_device *dev,
			     struct hbm_props_response *res)
{
	struct mei_me_client *me_cl;

	me_cl = kzalloc(sizeof(struct mei_me_client), GFP_KERNEL);
	if (!me_cl)
		return -ENOMEM;

	me_cl->props = res->client_properties;
	me_cl->client_id = res->me_addr;
	me_cl->mei_flow_ctrl_creds = 0;

	list_add(&me_cl->list, &dev->me_clients);
	return 0;
}

/**
 * mei_hbm_prop_req - request property for a single client
 *
 * @dev: the device structure
 *
 * Return: 0 on success and < 0 on failure
 */

static int mei_hbm_prop_req(struct mei_device *dev)
{

	struct mei_msg_hdr *mei_hdr = &dev->wr_msg.hdr;
	struct hbm_props_request *prop_req;
	const size_t len = sizeof(struct hbm_props_request);
	unsigned long next_client_index;
	int ret;

	next_client_index = find_next_bit(dev->me_clients_map, MEI_CLIENTS_MAX,
					  dev->me_client_index);

	/* We got all client properties */
	if (next_client_index == MEI_CLIENTS_MAX) {
		dev->hbm_state = MEI_HBM_STARTED;
		schedule_work(&dev->init_work);

		return 0;
	}

	mei_hbm_hdr(mei_hdr, len);
	prop_req = (struct hbm_props_request *)dev->wr_msg.data;

	memset(prop_req, 0, sizeof(struct hbm_props_request));

	prop_req->hbm_cmd = HOST_CLIENT_PROPERTIES_REQ_CMD;
	prop_req->me_addr = next_client_index;

	ret = mei_write_message(dev, mei_hdr, dev->wr_msg.data);
	if (ret) {
		dev_err(dev->dev, "properties request write failed: ret = %d\n",
			ret);
		return ret;
	}

	dev->init_clients_timer = MEI_CLIENTS_INIT_TIMEOUT;
	dev->me_client_index = next_client_index;

	return 0;
}

/*
 * mei_hbm_pg - sends pg command
 *
 * @dev: the device structure
 * @pg_cmd: the pg command code
 *
 * Return: -EIO on write failure
 *         -EOPNOTSUPP if the operation is not supported by the protocol
 */
int mei_hbm_pg(struct mei_device *dev, u8 pg_cmd)
{
	struct mei_msg_hdr *mei_hdr = &dev->wr_msg.hdr;
	struct hbm_power_gate *req;
	const size_t len = sizeof(struct hbm_power_gate);
	int ret;

	if (!dev->hbm_f_pg_supported)
		return -EOPNOTSUPP;

	mei_hbm_hdr(mei_hdr, len);

	req = (struct hbm_power_gate *)dev->wr_msg.data;
	memset(req, 0, len);
	req->hbm_cmd = pg_cmd;

	ret = mei_write_message(dev, mei_hdr, dev->wr_msg.data);
	if (ret)
		dev_err(dev->dev, "power gate command write failed.\n");
	return ret;
}
EXPORT_SYMBOL_GPL(mei_hbm_pg);

/**
 * mei_hbm_stop_req - send stop request message
 *
 * @dev: mei device
 *
 * Return: -EIO on write failure
 */
static int mei_hbm_stop_req(struct mei_device *dev)
{
	struct mei_msg_hdr *mei_hdr = &dev->wr_msg.hdr;
	struct hbm_host_stop_request *req =
			(struct hbm_host_stop_request *)dev->wr_msg.data;
	const size_t len = sizeof(struct hbm_host_stop_request);

	mei_hbm_hdr(mei_hdr, len);

	memset(req, 0, len);
	req->hbm_cmd = HOST_STOP_REQ_CMD;
	req->reason = DRIVER_STOP_REQUEST;

	return mei_write_message(dev, mei_hdr, dev->wr_msg.data);
}

/**
 * mei_hbm_cl_flow_control_req - sends flow control request.
 *
 * @dev: the device structure
 * @cl: client info
 *
 * Return: -EIO on write failure
 */
int mei_hbm_cl_flow_control_req(struct mei_device *dev, struct mei_cl *cl)
{
	const size_t len = sizeof(struct hbm_flow_control);

	cl_dbg(dev, cl, "sending flow control\n");
	return mei_hbm_cl_write(dev, cl, MEI_FLOW_CONTROL_CMD, len);
}

/**
 * mei_hbm_add_single_flow_creds - adds single buffer credentials.
 *
 * @dev: the device structure
 * @flow: flow control.
 *
 * Return: 0 on success, < 0 otherwise
 */
static int mei_hbm_add_single_flow_creds(struct mei_device *dev,
				  struct hbm_flow_control *flow)
{
	struct mei_me_client *me_cl;

	me_cl = mei_me_cl_by_id(dev, flow->me_addr);
	if (!me_cl) {
		dev_err(dev->dev, "no such me client %d\n",
			flow->me_addr);
		return -ENOENT;
	}

	if (WARN_ON(me_cl->props.single_recv_buf == 0))
		return -EINVAL;

	me_cl->mei_flow_ctrl_creds++;
	dev_dbg(dev->dev, "recv flow ctrl msg ME %d (single) creds = %d.\n",
	    flow->me_addr, me_cl->mei_flow_ctrl_creds);

	return 0;
}

/**
 * mei_hbm_cl_flow_control_res - flow control response from me
 *
 * @dev: the device structure
 * @flow_control: flow control response bus message
 */
static void mei_hbm_cl_flow_control_res(struct mei_device *dev,
					struct hbm_flow_control *flow_control)
{
	struct mei_cl *cl;

	if (!flow_control->host_addr) {
		/* single receive buffer */
		mei_hbm_add_single_flow_creds(dev, flow_control);
		return;
	}

	cl = mei_hbm_cl_find_by_cmd(dev, flow_control);
	if (cl) {
		cl->mei_flow_ctrl_creds++;
		cl_dbg(dev, cl, "flow control creds = %d.\n",
				cl->mei_flow_ctrl_creds);
	}
}


/**
 * mei_hbm_cl_disconnect_req - sends disconnect message to fw.
 *
 * @dev: the device structure
 * @cl: a client to disconnect from
 *
 * Return: -EIO on write failure
 */
int mei_hbm_cl_disconnect_req(struct mei_device *dev, struct mei_cl *cl)
{
	const size_t len = sizeof(struct hbm_client_connect_request);

	return mei_hbm_cl_write(dev, cl, CLIENT_DISCONNECT_REQ_CMD, len);
}

/**
 * mei_hbm_cl_disconnect_rsp - sends disconnect respose to the FW
 *
 * @dev: the device structure
 * @cl: a client to disconnect from
 *
 * Return: -EIO on write failure
 */
int mei_hbm_cl_disconnect_rsp(struct mei_device *dev, struct mei_cl *cl)
{
	const size_t len = sizeof(struct hbm_client_connect_response);

	return mei_hbm_cl_write(dev, cl, CLIENT_DISCONNECT_RES_CMD, len);
}

/**
 * mei_hbm_cl_disconnect_res - update the client state according
 *       disconnect response
 *
 * @dev: the device structure
 * @cl: mei host client
 * @cmd: disconnect client response host bus message
 */
static void mei_hbm_cl_disconnect_res(struct mei_device *dev, struct mei_cl *cl,
				      struct mei_hbm_cl_cmd *cmd)
{
	struct hbm_client_connect_response *rs =
		(struct hbm_client_connect_response *)cmd;

	cl_dbg(dev, cl, "hbm: disconnect response status=%d\n", rs->status);

	if (rs->status == MEI_CL_DISCONN_SUCCESS)
		cl->state = MEI_FILE_DISCONNECTED;
	cl->status = 0;
}

/**
 * mei_hbm_cl_connect_req - send connection request to specific me client
 *
 * @dev: the device structure
 * @cl: a client to connect to
 *
 * Return: -EIO on write failure
 */
int mei_hbm_cl_connect_req(struct mei_device *dev, struct mei_cl *cl)
{
	const size_t len = sizeof(struct hbm_client_connect_request);

	return mei_hbm_cl_write(dev, cl, CLIENT_CONNECT_REQ_CMD, len);
}

/**
 * mei_hbm_cl_connect_res - update the client state according
 *        connection response
 *
 * @dev: the device structure
 * @cl: mei host client
 * @cmd: connect client response host bus message
 */
static void mei_hbm_cl_connect_res(struct mei_device *dev, struct mei_cl *cl,
				   struct mei_hbm_cl_cmd *cmd)
{
	struct hbm_client_connect_response *rs =
		(struct hbm_client_connect_response *)cmd;

	cl_dbg(dev, cl, "hbm: connect response status=%s\n",
			mei_cl_conn_status_str(rs->status));

	if (rs->status == MEI_CL_CONN_SUCCESS)
		cl->state = MEI_FILE_CONNECTED;
	else
		cl->state = MEI_FILE_DISCONNECTED;
	cl->status = mei_cl_conn_status_to_errno(rs->status);
}

/**
 * mei_hbm_cl_res - process hbm response received on behalf
 *         an client
 *
 * @dev: the device structure
 * @rs:  hbm client message
 * @fop_type: file operation type
 */
static void mei_hbm_cl_res(struct mei_device *dev,
			   struct mei_hbm_cl_cmd *rs,
			   enum mei_cb_file_ops fop_type)
{
	struct mei_cl *cl;
	struct mei_cl_cb *cb, *next;

	cl = NULL;
	list_for_each_entry_safe(cb, next, &dev->ctrl_rd_list.list, list) {

		cl = cb->cl;

		if (cb->fop_type != fop_type)
			continue;

		if (mei_hbm_cl_addr_equal(cl, rs)) {
			list_del(&cb->list);
			break;
		}
	}

	if (!cl)
		return;

	switch (fop_type) {
	case MEI_FOP_CONNECT:
		mei_hbm_cl_connect_res(dev, cl, rs);
		break;
	case MEI_FOP_DISCONNECT:
		mei_hbm_cl_disconnect_res(dev, cl, rs);
		break;
	default:
		return;
	}

	cl->timer_count = 0;
	wake_up(&cl->wait);
}


/**
 * mei_hbm_fw_disconnect_req - disconnect request initiated by ME firmware
 *  host sends disconnect response
 *
 * @dev: the device structure.
 * @disconnect_req: disconnect request bus message from the me
 *
 * Return: -ENOMEM on allocation failure
 */
static int mei_hbm_fw_disconnect_req(struct mei_device *dev,
		struct hbm_client_connect_request *disconnect_req)
{
	struct mei_cl *cl;
	struct mei_cl_cb *cb;

	cl = mei_hbm_cl_find_by_cmd(dev, disconnect_req);
	if (cl) {
		cl_dbg(dev, cl, "disconnect request received\n");
		cl->state = MEI_FILE_DISCONNECTED;
		cl->timer_count = 0;

		cb = mei_io_cb_init(cl, NULL);
		if (!cb)
			return -ENOMEM;
		cb->fop_type = MEI_FOP_DISCONNECT_RSP;
		cl_dbg(dev, cl, "add disconnect response as first\n");
		list_add(&cb->list, &dev->ctrl_wr_list.list);
	}
	return 0;
}

/**
 * mei_hbm_config_features - check what hbm features and commands
 *        are supported by the fw
 *
 * @dev: the device structure
 */
static void mei_hbm_config_features(struct mei_device *dev)
{
	/* Power Gating Isolation Support */
	dev->hbm_f_pg_supported = 0;
	if (dev->version.major_version > HBM_MAJOR_VERSION_PGI)
		dev->hbm_f_pg_supported = 1;

	if (dev->version.major_version == HBM_MAJOR_VERSION_PGI &&
	    dev->version.minor_version >= HBM_MINOR_VERSION_PGI)
		dev->hbm_f_pg_supported = 1;
}

/**
 * mei_hbm_version_is_supported - checks whether the driver can
 *     support the hbm version of the device
 *
 * @dev: the device structure
 * Return: true if driver can support hbm version of the device
 */
bool mei_hbm_version_is_supported(struct mei_device *dev)
{
	return	(dev->version.major_version < HBM_MAJOR_VERSION) ||
		(dev->version.major_version == HBM_MAJOR_VERSION &&
		 dev->version.minor_version <= HBM_MINOR_VERSION);
}

/**
 * mei_hbm_dispatch - bottom half read routine after ISR to
 * handle the read bus message cmd processing.
 *
 * @dev: the device structure
 * @hdr: header of bus message
 *
 * Return: 0 on success and < 0 on failure
 */
int mei_hbm_dispatch(struct mei_device *dev, struct mei_msg_hdr *hdr)
{
	struct mei_bus_message *mei_msg;
	struct hbm_host_version_response *version_res;
	struct hbm_props_response *props_res;
	struct hbm_host_enum_response *enum_res;

	struct mei_hbm_cl_cmd *cl_cmd;
	struct hbm_client_connect_request *disconnect_req;
	struct hbm_flow_control *flow_control;

	/* read the message to our buffer */
	BUG_ON(hdr->length >= sizeof(dev->rd_msg_buf));
	mei_read_slots(dev, dev->rd_msg_buf, hdr->length);
	mei_msg = (struct mei_bus_message *)dev->rd_msg_buf;
	cl_cmd  = (struct mei_hbm_cl_cmd *)mei_msg;

	/* ignore spurious message and prevent reset nesting
	 * hbm is put to idle during system reset
	 */
	if (dev->hbm_state == MEI_HBM_IDLE) {
		dev_dbg(dev->dev, "hbm: state is idle ignore spurious messages\n");
		return 0;
	}

	switch (mei_msg->hbm_cmd) {
	case HOST_START_RES_CMD:
		dev_dbg(dev->dev, "hbm: start: response message received.\n");

		dev->init_clients_timer = 0;

		version_res = (struct hbm_host_version_response *)mei_msg;

		dev_dbg(dev->dev, "HBM VERSION: DRIVER=%02d:%02d DEVICE=%02d:%02d\n",
				HBM_MAJOR_VERSION, HBM_MINOR_VERSION,
				version_res->me_max_version.major_version,
				version_res->me_max_version.minor_version);

		if (version_res->host_version_supported) {
			dev->version.major_version = HBM_MAJOR_VERSION;
			dev->version.minor_version = HBM_MINOR_VERSION;
		} else {
			dev->version.major_version =
				version_res->me_max_version.major_version;
			dev->version.minor_version =
				version_res->me_max_version.minor_version;
		}

		if (!mei_hbm_version_is_supported(dev)) {
			dev_warn(dev->dev, "hbm: start: version mismatch - stopping the driver.\n");

			dev->hbm_state = MEI_HBM_STOPPED;
			if (mei_hbm_stop_req(dev)) {
				dev_err(dev->dev, "hbm: start: failed to send stop request\n");
				return -EIO;
			}
			break;
		}

		mei_hbm_config_features(dev);

		if (dev->dev_state != MEI_DEV_INIT_CLIENTS ||
		    dev->hbm_state != MEI_HBM_STARTING) {
			dev_err(dev->dev, "hbm: start: state mismatch, [%d, %d]\n",
				dev->dev_state, dev->hbm_state);
			return -EPROTO;
		}

		if (mei_hbm_enum_clients_req(dev)) {
			dev_err(dev->dev, "hbm: start: failed to send enumeration request\n");
			return -EIO;
		}

		wake_up(&dev->wait_hbm_start);
		break;

	case CLIENT_CONNECT_RES_CMD:
		dev_dbg(dev->dev, "hbm: client connect response: message received.\n");
		mei_hbm_cl_res(dev, cl_cmd, MEI_FOP_CONNECT);
		break;

	case CLIENT_DISCONNECT_RES_CMD:
		dev_dbg(dev->dev, "hbm: client disconnect response: message received.\n");
		mei_hbm_cl_res(dev, cl_cmd, MEI_FOP_DISCONNECT);
		break;

	case MEI_FLOW_CONTROL_CMD:
		dev_dbg(dev->dev, "hbm: client flow control response: message received.\n");

		flow_control = (struct hbm_flow_control *) mei_msg;
		mei_hbm_cl_flow_control_res(dev, flow_control);
		break;

	case MEI_PG_ISOLATION_ENTRY_RES_CMD:
		dev_dbg(dev->dev, "power gate isolation entry response received\n");
		dev->pg_event = MEI_PG_EVENT_RECEIVED;
		if (waitqueue_active(&dev->wait_pg))
			wake_up(&dev->wait_pg);
		break;

	case MEI_PG_ISOLATION_EXIT_REQ_CMD:
		dev_dbg(dev->dev, "power gate isolation exit request received\n");
		dev->pg_event = MEI_PG_EVENT_RECEIVED;
		if (waitqueue_active(&dev->wait_pg))
			wake_up(&dev->wait_pg);
		else
			/*
			* If the driver is not waiting on this then
			* this is HW initiated exit from PG.
			* Start runtime pm resume sequence to exit from PG.
			*/
			pm_request_resume(dev->dev);
		break;

	case HOST_CLIENT_PROPERTIES_RES_CMD:
		dev_dbg(dev->dev, "hbm: properties response: message received.\n");

		dev->init_clients_timer = 0;

		if (dev->dev_state != MEI_DEV_INIT_CLIENTS ||
		    dev->hbm_state != MEI_HBM_CLIENT_PROPERTIES) {
			dev_err(dev->dev, "hbm: properties response: state mismatch, [%d, %d]\n",
				dev->dev_state, dev->hbm_state);
			return -EPROTO;
		}

		props_res = (struct hbm_props_response *)mei_msg;

		if (props_res->status) {
			dev_err(dev->dev, "hbm: properties response: wrong status = %d %s\n",
				props_res->status,
				mei_hbm_status_str(props_res->status));
			return -EPROTO;
		}

		mei_hbm_me_cl_add(dev, props_res);

		dev->me_client_index++;

		/* request property for the next client */
		if (mei_hbm_prop_req(dev))
			return -EIO;

		break;

	case HOST_ENUM_RES_CMD:
		dev_dbg(dev->dev, "hbm: enumeration response: message received\n");

		dev->init_clients_timer = 0;

		enum_res = (struct hbm_host_enum_response *) mei_msg;
		BUILD_BUG_ON(sizeof(dev->me_clients_map)
				< sizeof(enum_res->valid_addresses));
		memcpy(dev->me_clients_map, enum_res->valid_addresses,
				sizeof(enum_res->valid_addresses));

		if (dev->dev_state != MEI_DEV_INIT_CLIENTS ||
		    dev->hbm_state != MEI_HBM_ENUM_CLIENTS) {
			dev_err(dev->dev, "hbm: enumeration response: state mismatch, [%d, %d]\n",
				dev->dev_state, dev->hbm_state);
			return -EPROTO;
		}

		dev->hbm_state = MEI_HBM_CLIENT_PROPERTIES;

		/* first property request */
		if (mei_hbm_prop_req(dev))
			return -EIO;

		break;

	case HOST_STOP_RES_CMD:
		dev_dbg(dev->dev, "hbm: stop response: message received\n");

		dev->init_clients_timer = 0;

		if (dev->hbm_state != MEI_HBM_STOPPED) {
			dev_err(dev->dev, "hbm: stop response: state mismatch, [%d, %d]\n",
				dev->dev_state, dev->hbm_state);
			return -EPROTO;
		}

		dev->dev_state = MEI_DEV_POWER_DOWN;
		dev_info(dev->dev, "hbm: stop response: resetting.\n");
		/* force the reset */
		return -EPROTO;
		break;

	case CLIENT_DISCONNECT_REQ_CMD:
		dev_dbg(dev->dev, "hbm: disconnect request: message received\n");

		disconnect_req = (struct hbm_client_connect_request *)mei_msg;
		mei_hbm_fw_disconnect_req(dev, disconnect_req);
		break;

	case ME_STOP_REQ_CMD:
		dev_dbg(dev->dev, "hbm: stop request: message received\n");
		dev->hbm_state = MEI_HBM_STOPPED;
		if (mei_hbm_stop_req(dev)) {
			dev_err(dev->dev, "hbm: stop request: failed to send stop request\n");
			return -EIO;
		}
		break;
	default:
		BUG();
		break;

	}
	return 0;
}