summaryrefslogtreecommitdiff
path: root/drivers/misc/mei/mei_dev.h
blob: db78e6d994568e535902fa045a21c68091d4812f (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
/*
 *
 * 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.
 *
 */

#ifndef _MEI_DEV_H_
#define _MEI_DEV_H_

#include <linux/types.h>
#include <linux/cdev.h>
#include <linux/poll.h>
#include <linux/mei.h>
#include <linux/mei_cl_bus.h>

#include "hw.h"
#include "hbm.h"


/*
 * AMTHI Client UUID
 */
extern const uuid_le mei_amthif_guid;

#define MEI_RD_MSG_BUF_SIZE           (128 * sizeof(u32))

/*
 * Number of Maximum MEI Clients
 */
#define MEI_CLIENTS_MAX 256

/*
 * maximum number of consecutive resets
 */
#define MEI_MAX_CONSEC_RESET  3

/*
 * Number of File descriptors/handles
 * that can be opened to the driver.
 *
 * Limit to 255: 256 Total Clients
 * minus internal client for MEI Bus Messages
 */
#define  MEI_MAX_OPEN_HANDLE_COUNT (MEI_CLIENTS_MAX - 1)

/* File state */
enum file_state {
	MEI_FILE_INITIALIZING = 0,
	MEI_FILE_CONNECTING,
	MEI_FILE_CONNECTED,
	MEI_FILE_DISCONNECTING,
	MEI_FILE_DISCONNECT_REPLY,
	MEI_FILE_DISCONNECT_REQUIRED,
	MEI_FILE_DISCONNECTED,
};

/* MEI device states */
enum mei_dev_state {
	MEI_DEV_INITIALIZING = 0,
	MEI_DEV_INIT_CLIENTS,
	MEI_DEV_ENABLED,
	MEI_DEV_RESETTING,
	MEI_DEV_DISABLED,
	MEI_DEV_POWER_DOWN,
	MEI_DEV_POWER_UP
};

const char *mei_dev_state_str(int state);

enum iamthif_states {
	MEI_IAMTHIF_IDLE,
	MEI_IAMTHIF_WRITING,
	MEI_IAMTHIF_FLOW_CONTROL,
	MEI_IAMTHIF_READING,
	MEI_IAMTHIF_READ_COMPLETE
};

enum mei_file_transaction_states {
	MEI_IDLE,
	MEI_WRITING,
	MEI_WRITE_COMPLETE,
	MEI_FLOW_CONTROL,
	MEI_READING,
	MEI_READ_COMPLETE
};

/**
 * enum mei_cb_file_ops  - file operation associated with the callback
 * @MEI_FOP_READ:       read
 * @MEI_FOP_WRITE:      write
 * @MEI_FOP_CONNECT:    connect
 * @MEI_FOP_DISCONNECT: disconnect
 * @MEI_FOP_DISCONNECT_RSP: disconnect response
 * @MEI_FOP_NOTIFY_START:   start notification
 * @MEI_FOP_NOTIFY_STOP:    stop notification
 */
enum mei_cb_file_ops {
	MEI_FOP_READ = 0,
	MEI_FOP_WRITE,
	MEI_FOP_CONNECT,
	MEI_FOP_DISCONNECT,
	MEI_FOP_DISCONNECT_RSP,
	MEI_FOP_NOTIFY_START,
	MEI_FOP_NOTIFY_STOP,
};

/*
 * Intel MEI message data struct
 */
struct mei_msg_data {
	size_t size;
	unsigned char *data;
};

/* Maximum number of processed FW status registers */
#define MEI_FW_STATUS_MAX 6
/* Minimal  buffer for FW status string (8 bytes in dw + space or '\0') */
#define MEI_FW_STATUS_STR_SZ (MEI_FW_STATUS_MAX * (8 + 1))


/*
 * struct mei_fw_status - storage of FW status data
 *
 * @count: number of actually available elements in array
 * @status: FW status registers
 */
struct mei_fw_status {
	int count;
	u32 status[MEI_FW_STATUS_MAX];
};

/**
 * struct mei_me_client - representation of me (fw) client
 *
 * @list: link in me client list
 * @refcnt: struct reference count
 * @props: client properties
 * @client_id: me client id
 * @mei_flow_ctrl_creds: flow control credits
 * @connect_count: number connections to this client
 * @bus_added: added to bus
 */
struct mei_me_client {
	struct list_head list;
	struct kref refcnt;
	struct mei_client_properties props;
	u8 client_id;
	u8 mei_flow_ctrl_creds;
	u8 connect_count;
	u8 bus_added;
};


struct mei_cl;

/**
 * struct mei_cl_cb - file operation callback structure
 *
 * @list: link in callback queue
 * @cl: file client who is running this operation
 * @fop_type: file operation type
 * @buf: buffer for data associated with the callback
 * @buf_idx: last read index
 * @fp: pointer to file structure
 * @status: io status of the cb
 * @internal: communication between driver and FW flag
 * @completed: the transfer or reception has completed
 */
struct mei_cl_cb {
	struct list_head list;
	struct mei_cl *cl;
	enum mei_cb_file_ops fop_type;
	struct mei_msg_data buf;
	size_t buf_idx;
	const struct file *fp;
	int status;
	u32 internal:1;
	u32 completed:1;
};

/**
 * struct mei_cl - me client host representation
 *    carried in file->private_data
 *
 * @link: link in the clients list
 * @dev: mei parent device
 * @state: file operation state
 * @tx_wait: wait queue for tx completion
 * @rx_wait: wait queue for rx completion
 * @wait:  wait queue for management operation
 * @ev_wait: notification wait queue
 * @ev_async: event async notification
 * @status: connection status
 * @me_cl: fw client connected
 * @host_client_id: host id
 * @mei_flow_ctrl_creds: transmit flow credentials
 * @timer_count:  watchdog timer for operation completion
 * @reserved: reserved for alignment
 * @notify_en: notification - enabled/disabled
 * @notify_ev: pending notification event
 * @writing_state: state of the tx
 * @rd_pending: pending read credits
 * @rd_completed: completed read
 *
 * @cldev: device on the mei client bus
 */
struct mei_cl {
	struct list_head link;
	struct mei_device *dev;
	enum file_state state;
	wait_queue_head_t tx_wait;
	wait_queue_head_t rx_wait;
	wait_queue_head_t wait;
	wait_queue_head_t ev_wait;
	struct fasync_struct *ev_async;
	int status;
	struct mei_me_client *me_cl;
	u8 host_client_id;
	u8 mei_flow_ctrl_creds;
	u8 timer_count;
	u8 reserved;
	u8 notify_en;
	u8 notify_ev;
	enum mei_file_transaction_states writing_state;
	struct list_head rd_pending;
	struct list_head rd_completed;

	struct mei_cl_device *cldev;
};

/**
 * struct mei_hw_ops - hw specific ops
 *
 * @host_is_ready    : query for host readiness
 *
 * @hw_is_ready      : query if hw is ready
 * @hw_reset         : reset hw
 * @hw_start         : start hw after reset
 * @hw_config        : configure hw
 *
 * @fw_status        : get fw status registers
 * @pg_state         : power gating state of the device
 * @pg_in_transition : is device now in pg transition
 * @pg_is_enabled    : is power gating enabled
 *
 * @intr_clear       : clear pending interrupts
 * @intr_enable      : enable interrupts
 * @intr_disable     : disable interrupts
 *
 * @hbuf_free_slots  : query for write buffer empty slots
 * @hbuf_is_ready    : query if write buffer is empty
 * @hbuf_max_len     : query for write buffer max len
 *
 * @write            : write a message to FW
 *
 * @rdbuf_full_slots : query how many slots are filled
 *
 * @read_hdr         : get first 4 bytes (header)
 * @read             : read a buffer from the FW
 */
struct mei_hw_ops {

	bool (*host_is_ready)(struct mei_device *dev);

	bool (*hw_is_ready)(struct mei_device *dev);
	int (*hw_reset)(struct mei_device *dev, bool enable);
	int (*hw_start)(struct mei_device *dev);
	void (*hw_config)(struct mei_device *dev);


	int (*fw_status)(struct mei_device *dev, struct mei_fw_status *fw_sts);
	enum mei_pg_state (*pg_state)(struct mei_device *dev);
	bool (*pg_in_transition)(struct mei_device *dev);
	bool (*pg_is_enabled)(struct mei_device *dev);

	void (*intr_clear)(struct mei_device *dev);
	void (*intr_enable)(struct mei_device *dev);
	void (*intr_disable)(struct mei_device *dev);

	int (*hbuf_free_slots)(struct mei_device *dev);
	bool (*hbuf_is_ready)(struct mei_device *dev);
	size_t (*hbuf_max_len)(const struct mei_device *dev);

	int (*write)(struct mei_device *dev,
		     struct mei_msg_hdr *hdr,
		     unsigned char *buf);

	int (*rdbuf_full_slots)(struct mei_device *dev);

	u32 (*read_hdr)(const struct mei_device *dev);
	int (*read)(struct mei_device *dev,
		     unsigned char *buf, unsigned long len);
};

/* MEI bus API*/
void mei_cl_bus_rescan(struct mei_device *bus);
void mei_cl_bus_rescan_work(struct work_struct *work);
void mei_cl_bus_dev_fixup(struct mei_cl_device *dev);
ssize_t __mei_cl_send(struct mei_cl *cl, u8 *buf, size_t length,
			bool blocking);
ssize_t __mei_cl_recv(struct mei_cl *cl, u8 *buf, size_t length);
bool mei_cl_bus_rx_event(struct mei_cl *cl);
bool mei_cl_bus_notify_event(struct mei_cl *cl);
void mei_cl_bus_remove_devices(struct mei_device *bus);
int mei_cl_bus_init(void);
void mei_cl_bus_exit(void);

/**
 * enum mei_pg_event - power gating transition events
 *
 * @MEI_PG_EVENT_IDLE: the driver is not in power gating transition
 * @MEI_PG_EVENT_WAIT: the driver is waiting for a pg event to complete
 * @MEI_PG_EVENT_RECEIVED: the driver received pg event
 * @MEI_PG_EVENT_INTR_WAIT: the driver is waiting for a pg event interrupt
 * @MEI_PG_EVENT_INTR_RECEIVED: the driver received pg event interrupt
 */
enum mei_pg_event {
	MEI_PG_EVENT_IDLE,
	MEI_PG_EVENT_WAIT,
	MEI_PG_EVENT_RECEIVED,
	MEI_PG_EVENT_INTR_WAIT,
	MEI_PG_EVENT_INTR_RECEIVED,
};

/**
 * enum mei_pg_state - device internal power gating state
 *
 * @MEI_PG_OFF: device is not power gated - it is active
 * @MEI_PG_ON:  device is power gated - it is in lower power state
 */
enum mei_pg_state {
	MEI_PG_OFF = 0,
	MEI_PG_ON =  1,
};

const char *mei_pg_state_str(enum mei_pg_state state);

/**
 * struct mei_device -  MEI private device struct
 *
 * @dev         : device on a bus
 * @cdev        : character device
 * @minor       : minor number allocated for device
 *
 * @write_list  : write pending list
 * @write_waiting_list : write completion list
 * @ctrl_wr_list : pending control write list
 * @ctrl_rd_list : pending control read list
 *
 * @file_list   : list of opened handles
 * @open_handle_count: number of opened handles
 *
 * @device_lock : big device lock
 * @timer_work  : MEI timer delayed work (timeouts)
 *
 * @recvd_hw_ready : hw ready message received flag
 *
 * @wait_hw_ready : wait queue for receive HW ready message form FW
 * @wait_pg     : wait queue for receive PG message from FW
 * @wait_hbm_start : wait queue for receive HBM start message from FW
 *
 * @reset_count : number of consecutive resets
 * @dev_state   : device state
 * @hbm_state   : state of host bus message protocol
 * @init_clients_timer : HBM init handshake timeout
 *
 * @pg_event    : power gating event
 * @pg_domain   : runtime PM domain
 *
 * @rd_msg_buf  : control messages buffer
 * @rd_msg_hdr  : read message header storage
 *
 * @hbuf_depth  : depth of hardware host/write buffer is slots
 * @hbuf_is_ready : query if the host host/write buffer is ready
 * @wr_msg      : the buffer for hbm control messages
 *
 * @version     : HBM protocol version in use
 * @hbm_f_pg_supported  : hbm feature pgi protocol
 * @hbm_f_dc_supported  : hbm feature dynamic clients
 * @hbm_f_dot_supported : hbm feature disconnect on timeout
 * @hbm_f_ev_supported  : hbm feature event notification
 * @hbm_f_fa_supported  : hbm feature fixed address client
 * @hbm_f_ie_supported  : hbm feature immediate reply to enum request
 *
 * @me_clients_rwsem: rw lock over me_clients list
 * @me_clients  : list of FW clients
 * @me_clients_map : FW clients bit map
 * @host_clients_map : host clients id pool
 * @me_client_index : last FW client index in enumeration
 *
 * @allow_fixed_address: allow user space to connect a fixed client
 * @override_fixed_address: force allow fixed address behavior
 *
 * @amthif_cmd_list : amthif list for cmd waiting
 * @iamthif_fp : file for current amthif operation
 * @iamthif_cl  : amthif host client
 * @iamthif_current_cb : amthif current operation callback
 * @iamthif_open_count : number of opened amthif connections
 * @iamthif_stall_timer : timer to detect amthif hang
 * @iamthif_state : amthif processor state
 * @iamthif_canceled : current amthif command is canceled
 *
 * @reset_work  : work item for the device reset
 * @bus_rescan_work : work item for the bus rescan
 *
 * @device_list : mei client bus list
 * @cl_bus_lock : client bus list lock
 *
 * @dbgfs_dir   : debugfs mei root directory
 *
 * @ops:        : hw specific operations
 * @hw          : hw specific data
 */
struct mei_device {
	struct device *dev;
	struct cdev cdev;
	int minor;

	struct mei_cl_cb write_list;
	struct mei_cl_cb write_waiting_list;
	struct mei_cl_cb ctrl_wr_list;
	struct mei_cl_cb ctrl_rd_list;

	struct list_head file_list;
	long open_handle_count;

	struct mutex device_lock;
	struct delayed_work timer_work;

	bool recvd_hw_ready;
	/*
	 * waiting queue for receive message from FW
	 */
	wait_queue_head_t wait_hw_ready;
	wait_queue_head_t wait_pg;
	wait_queue_head_t wait_hbm_start;

	/*
	 * mei device  states
	 */
	unsigned long reset_count;
	enum mei_dev_state dev_state;
	enum mei_hbm_state hbm_state;
	u16 init_clients_timer;

	/*
	 * Power Gating support
	 */
	enum mei_pg_event pg_event;
#ifdef CONFIG_PM
	struct dev_pm_domain pg_domain;
#endif /* CONFIG_PM */

	unsigned char rd_msg_buf[MEI_RD_MSG_BUF_SIZE];
	u32 rd_msg_hdr;

	/* write buffer */
	u8 hbuf_depth;
	bool hbuf_is_ready;

	/* used for control messages */
	struct {
		struct mei_msg_hdr hdr;
		unsigned char data[128];
	} wr_msg;

	struct hbm_version version;
	unsigned int hbm_f_pg_supported:1;
	unsigned int hbm_f_dc_supported:1;
	unsigned int hbm_f_dot_supported:1;
	unsigned int hbm_f_ev_supported:1;
	unsigned int hbm_f_fa_supported:1;
	unsigned int hbm_f_ie_supported:1;

	struct rw_semaphore me_clients_rwsem;
	struct list_head me_clients;
	DECLARE_BITMAP(me_clients_map, MEI_CLIENTS_MAX);
	DECLARE_BITMAP(host_clients_map, MEI_CLIENTS_MAX);
	unsigned long me_client_index;

	bool allow_fixed_address;
	bool override_fixed_address;

	/* amthif list for cmd waiting */
	struct mei_cl_cb amthif_cmd_list;
	/* driver managed amthif list for reading completed amthif cmd data */
	const struct file *iamthif_fp;
	struct mei_cl iamthif_cl;
	struct mei_cl_cb *iamthif_current_cb;
	long iamthif_open_count;
	u32 iamthif_stall_timer;
	enum iamthif_states iamthif_state;
	bool iamthif_canceled;

	struct work_struct reset_work;
	struct work_struct bus_rescan_work;

	/* List of bus devices */
	struct list_head device_list;
	struct mutex cl_bus_lock;

#if IS_ENABLED(CONFIG_DEBUG_FS)
	struct dentry *dbgfs_dir;
#endif /* CONFIG_DEBUG_FS */


	const struct mei_hw_ops *ops;
	char hw[0] __aligned(sizeof(void *));
};

static inline unsigned long mei_secs_to_jiffies(unsigned long sec)
{
	return msecs_to_jiffies(sec * MSEC_PER_SEC);
}

/**
 * mei_data2slots - get slots - number of (dwords) from a message length
 *	+ size of the mei header
 *
 * @length: size of the messages in bytes
 *
 * Return: number of slots
 */
static inline u32 mei_data2slots(size_t length)
{
	return DIV_ROUND_UP(sizeof(struct mei_msg_hdr) + length, 4);
}

/**
 * mei_slots2data - get data in slots - bytes from slots
 *
 * @slots: number of available slots
 *
 * Return: number of bytes in slots
 */
static inline u32 mei_slots2data(int slots)
{
	return slots * 4;
}

/*
 * mei init function prototypes
 */
void mei_device_init(struct mei_device *dev,
		     struct device *device,
		     const struct mei_hw_ops *hw_ops);
int mei_reset(struct mei_device *dev);
int mei_start(struct mei_device *dev);
int mei_restart(struct mei_device *dev);
void mei_stop(struct mei_device *dev);
void mei_cancel_work(struct mei_device *dev);

/*
 *  MEI interrupt functions prototype
 */

void mei_timer(struct work_struct *work);
int mei_irq_read_handler(struct mei_device *dev,
		struct mei_cl_cb *cmpl_list, s32 *slots);

int mei_irq_write_handler(struct mei_device *dev, struct mei_cl_cb *cmpl_list);
void mei_irq_compl_handler(struct mei_device *dev, struct mei_cl_cb *cmpl_list);

/*
 * AMTHIF - AMT Host Interface Functions
 */
void mei_amthif_reset_params(struct mei_device *dev);

int mei_amthif_host_init(struct mei_device *dev, struct mei_me_client *me_cl);

int mei_amthif_read(struct mei_device *dev, struct file *file,
		char __user *ubuf, size_t length, loff_t *offset);

unsigned int mei_amthif_poll(struct mei_device *dev,
		struct file *file, poll_table *wait);

int mei_amthif_release(struct mei_device *dev, struct file *file);

int mei_amthif_write(struct mei_cl *cl, struct mei_cl_cb *cb);
int mei_amthif_run_next_cmd(struct mei_device *dev);
int mei_amthif_irq_write(struct mei_cl *cl, struct mei_cl_cb *cb,
			struct mei_cl_cb *cmpl_list);

void mei_amthif_complete(struct mei_cl *cl, struct mei_cl_cb *cb);
int mei_amthif_irq_read_msg(struct mei_cl *cl,
			    struct mei_msg_hdr *mei_hdr,
			    struct mei_cl_cb *complete_list);
int mei_amthif_irq_read(struct mei_device *dev, s32 *slots);

/*
 * Register Access Function
 */


static inline void mei_hw_config(struct mei_device *dev)
{
	dev->ops->hw_config(dev);
}

static inline enum mei_pg_state mei_pg_state(struct mei_device *dev)
{
	return dev->ops->pg_state(dev);
}

static inline bool mei_pg_in_transition(struct mei_device *dev)
{
	return dev->ops->pg_in_transition(dev);
}

static inline bool mei_pg_is_enabled(struct mei_device *dev)
{
	return dev->ops->pg_is_enabled(dev);
}

static inline int mei_hw_reset(struct mei_device *dev, bool enable)
{
	return dev->ops->hw_reset(dev, enable);
}

static inline int mei_hw_start(struct mei_device *dev)
{
	return dev->ops->hw_start(dev);
}

static inline void mei_clear_interrupts(struct mei_device *dev)
{
	dev->ops->intr_clear(dev);
}

static inline void mei_enable_interrupts(struct mei_device *dev)
{
	dev->ops->intr_enable(dev);
}

static inline void mei_disable_interrupts(struct mei_device *dev)
{
	dev->ops->intr_disable(dev);
}

static inline bool mei_host_is_ready(struct mei_device *dev)
{
	return dev->ops->host_is_ready(dev);
}
static inline bool mei_hw_is_ready(struct mei_device *dev)
{
	return dev->ops->hw_is_ready(dev);
}

static inline bool mei_hbuf_is_ready(struct mei_device *dev)
{
	return dev->ops->hbuf_is_ready(dev);
}

static inline int mei_hbuf_empty_slots(struct mei_device *dev)
{
	return dev->ops->hbuf_free_slots(dev);
}

static inline size_t mei_hbuf_max_len(const struct mei_device *dev)
{
	return dev->ops->hbuf_max_len(dev);
}

static inline int mei_write_message(struct mei_device *dev,
			struct mei_msg_hdr *hdr,
			unsigned char *buf)
{
	return dev->ops->write(dev, hdr, buf);
}

static inline u32 mei_read_hdr(const struct mei_device *dev)
{
	return dev->ops->read_hdr(dev);
}

static inline void mei_read_slots(struct mei_device *dev,
		     unsigned char *buf, unsigned long len)
{
	dev->ops->read(dev, buf, len);
}

static inline int mei_count_full_read_slots(struct mei_device *dev)
{
	return dev->ops->rdbuf_full_slots(dev);
}

static inline int mei_fw_status(struct mei_device *dev,
				struct mei_fw_status *fw_status)
{
	return dev->ops->fw_status(dev, fw_status);
}

bool mei_hbuf_acquire(struct mei_device *dev);

bool mei_write_is_idle(struct mei_device *dev);

#if IS_ENABLED(CONFIG_DEBUG_FS)
int mei_dbgfs_register(struct mei_device *dev, const char *name);
void mei_dbgfs_deregister(struct mei_device *dev);
#else
static inline int mei_dbgfs_register(struct mei_device *dev, const char *name)
{
	return 0;
}
static inline void mei_dbgfs_deregister(struct mei_device *dev) {}
#endif /* CONFIG_DEBUG_FS */

int mei_register(struct mei_device *dev, struct device *parent);
void mei_deregister(struct mei_device *dev);

#define MEI_HDR_FMT "hdr:host=%02d me=%02d len=%d internal=%1d comp=%1d"
#define MEI_HDR_PRM(hdr)                  \
	(hdr)->host_addr, (hdr)->me_addr, \
	(hdr)->length, (hdr)->internal, (hdr)->msg_complete

ssize_t mei_fw_status2str(struct mei_fw_status *fw_sts, char *buf, size_t len);
/**
 * mei_fw_status_str - fetch and convert fw status registers to printable string
 *
 * @dev: the device structure
 * @buf: string buffer at minimal size MEI_FW_STATUS_STR_SZ
 * @len: buffer len must be >= MEI_FW_STATUS_STR_SZ
 *
 * Return: number of bytes written or < 0 on failure
 */
static inline ssize_t mei_fw_status_str(struct mei_device *dev,
					char *buf, size_t len)
{
	struct mei_fw_status fw_status;
	int ret;

	buf[0] = '\0';

	ret = mei_fw_status(dev, &fw_status);
	if (ret)
		return ret;

	ret = mei_fw_status2str(&fw_status, buf, MEI_FW_STATUS_STR_SZ);

	return ret;
}


#endif