xref: /openbmc/linux/drivers/misc/mei/mei_dev.h (revision 4f6cce39)
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 #ifndef _MEI_DEV_H_
18 #define _MEI_DEV_H_
19 
20 #include <linux/types.h>
21 #include <linux/cdev.h>
22 #include <linux/poll.h>
23 #include <linux/mei.h>
24 #include <linux/mei_cl_bus.h>
25 
26 #include "hw.h"
27 #include "hbm.h"
28 
29 
30 /*
31  * AMTHI Client UUID
32  */
33 extern const uuid_le mei_amthif_guid;
34 
35 #define MEI_RD_MSG_BUF_SIZE           (128 * sizeof(u32))
36 
37 /*
38  * Number of Maximum MEI Clients
39  */
40 #define MEI_CLIENTS_MAX 256
41 
42 /*
43  * maximum number of consecutive resets
44  */
45 #define MEI_MAX_CONSEC_RESET  3
46 
47 /*
48  * Number of File descriptors/handles
49  * that can be opened to the driver.
50  *
51  * Limit to 255: 256 Total Clients
52  * minus internal client for MEI Bus Messages
53  */
54 #define  MEI_MAX_OPEN_HANDLE_COUNT (MEI_CLIENTS_MAX - 1)
55 
56 /* File state */
57 enum file_state {
58 	MEI_FILE_UNINITIALIZED = 0,
59 	MEI_FILE_INITIALIZING,
60 	MEI_FILE_CONNECTING,
61 	MEI_FILE_CONNECTED,
62 	MEI_FILE_DISCONNECTING,
63 	MEI_FILE_DISCONNECT_REPLY,
64 	MEI_FILE_DISCONNECT_REQUIRED,
65 	MEI_FILE_DISCONNECTED,
66 };
67 
68 /* MEI device states */
69 enum mei_dev_state {
70 	MEI_DEV_INITIALIZING = 0,
71 	MEI_DEV_INIT_CLIENTS,
72 	MEI_DEV_ENABLED,
73 	MEI_DEV_RESETTING,
74 	MEI_DEV_DISABLED,
75 	MEI_DEV_POWER_DOWN,
76 	MEI_DEV_POWER_UP
77 };
78 
79 const char *mei_dev_state_str(int state);
80 
81 enum iamthif_states {
82 	MEI_IAMTHIF_IDLE,
83 	MEI_IAMTHIF_WRITING,
84 	MEI_IAMTHIF_READING,
85 };
86 
87 enum mei_file_transaction_states {
88 	MEI_IDLE,
89 	MEI_WRITING,
90 	MEI_WRITE_COMPLETE,
91 };
92 
93 /**
94  * enum mei_cb_file_ops  - file operation associated with the callback
95  * @MEI_FOP_READ:       read
96  * @MEI_FOP_WRITE:      write
97  * @MEI_FOP_CONNECT:    connect
98  * @MEI_FOP_DISCONNECT: disconnect
99  * @MEI_FOP_DISCONNECT_RSP: disconnect response
100  * @MEI_FOP_NOTIFY_START:   start notification
101  * @MEI_FOP_NOTIFY_STOP:    stop notification
102  */
103 enum mei_cb_file_ops {
104 	MEI_FOP_READ = 0,
105 	MEI_FOP_WRITE,
106 	MEI_FOP_CONNECT,
107 	MEI_FOP_DISCONNECT,
108 	MEI_FOP_DISCONNECT_RSP,
109 	MEI_FOP_NOTIFY_START,
110 	MEI_FOP_NOTIFY_STOP,
111 };
112 
113 /**
114  * enum mei_cl_io_mode - io mode between driver and fw
115  *
116  * @MEI_CL_IO_TX_BLOCKING: send is blocking
117  * @MEI_CL_IO_TX_INTERNAL: internal communication between driver and FW
118  *
119  * @MEI_CL_IO_RX_NONBLOCK: recv is non-blocking
120  */
121 enum mei_cl_io_mode {
122 	MEI_CL_IO_TX_BLOCKING = BIT(0),
123 	MEI_CL_IO_TX_INTERNAL = BIT(1),
124 
125 	MEI_CL_IO_RX_NONBLOCK = BIT(2),
126 };
127 
128 /*
129  * Intel MEI message data struct
130  */
131 struct mei_msg_data {
132 	size_t size;
133 	unsigned char *data;
134 };
135 
136 /* Maximum number of processed FW status registers */
137 #define MEI_FW_STATUS_MAX 6
138 /* Minimal  buffer for FW status string (8 bytes in dw + space or '\0') */
139 #define MEI_FW_STATUS_STR_SZ (MEI_FW_STATUS_MAX * (8 + 1))
140 
141 
142 /*
143  * struct mei_fw_status - storage of FW status data
144  *
145  * @count: number of actually available elements in array
146  * @status: FW status registers
147  */
148 struct mei_fw_status {
149 	int count;
150 	u32 status[MEI_FW_STATUS_MAX];
151 };
152 
153 /**
154  * struct mei_me_client - representation of me (fw) client
155  *
156  * @list: link in me client list
157  * @refcnt: struct reference count
158  * @props: client properties
159  * @client_id: me client id
160  * @tx_flow_ctrl_creds: flow control credits
161  * @connect_count: number connections to this client
162  * @bus_added: added to bus
163  */
164 struct mei_me_client {
165 	struct list_head list;
166 	struct kref refcnt;
167 	struct mei_client_properties props;
168 	u8 client_id;
169 	u8 tx_flow_ctrl_creds;
170 	u8 connect_count;
171 	u8 bus_added;
172 };
173 
174 
175 struct mei_cl;
176 
177 /**
178  * struct mei_cl_cb - file operation callback structure
179  *
180  * @list: link in callback queue
181  * @cl: file client who is running this operation
182  * @fop_type: file operation type
183  * @buf: buffer for data associated with the callback
184  * @buf_idx: last read index
185  * @fp: pointer to file structure
186  * @status: io status of the cb
187  * @internal: communication between driver and FW flag
188  * @blocking: transmission blocking mode
189  * @completed: the transfer or reception has completed
190  */
191 struct mei_cl_cb {
192 	struct list_head list;
193 	struct mei_cl *cl;
194 	enum mei_cb_file_ops fop_type;
195 	struct mei_msg_data buf;
196 	size_t buf_idx;
197 	const struct file *fp;
198 	int status;
199 	u32 internal:1;
200 	u32 blocking:1;
201 	u32 completed:1;
202 };
203 
204 /**
205  * struct mei_cl - me client host representation
206  *    carried in file->private_data
207  *
208  * @link: link in the clients list
209  * @dev: mei parent device
210  * @state: file operation state
211  * @tx_wait: wait queue for tx completion
212  * @rx_wait: wait queue for rx completion
213  * @wait:  wait queue for management operation
214  * @ev_wait: notification wait queue
215  * @ev_async: event async notification
216  * @status: connection status
217  * @me_cl: fw client connected
218  * @fp: file associated with client
219  * @host_client_id: host id
220  * @tx_flow_ctrl_creds: transmit flow credentials
221  * @rx_flow_ctrl_creds: receive flow credentials
222  * @timer_count:  watchdog timer for operation completion
223  * @notify_en: notification - enabled/disabled
224  * @notify_ev: pending notification event
225  * @writing_state: state of the tx
226  * @rd_pending: pending read credits
227  * @rd_completed: completed read
228  *
229  * @cldev: device on the mei client bus
230  */
231 struct mei_cl {
232 	struct list_head link;
233 	struct mei_device *dev;
234 	enum file_state state;
235 	wait_queue_head_t tx_wait;
236 	wait_queue_head_t rx_wait;
237 	wait_queue_head_t wait;
238 	wait_queue_head_t ev_wait;
239 	struct fasync_struct *ev_async;
240 	int status;
241 	struct mei_me_client *me_cl;
242 	const struct file *fp;
243 	u8 host_client_id;
244 	u8 tx_flow_ctrl_creds;
245 	u8 rx_flow_ctrl_creds;
246 	u8 timer_count;
247 	u8 notify_en;
248 	u8 notify_ev;
249 	enum mei_file_transaction_states writing_state;
250 	struct list_head rd_pending;
251 	struct list_head rd_completed;
252 
253 	struct mei_cl_device *cldev;
254 };
255 
256 /**
257  * struct mei_hw_ops - hw specific ops
258  *
259  * @host_is_ready    : query for host readiness
260  *
261  * @hw_is_ready      : query if hw is ready
262  * @hw_reset         : reset hw
263  * @hw_start         : start hw after reset
264  * @hw_config        : configure hw
265  *
266  * @fw_status        : get fw status registers
267  * @pg_state         : power gating state of the device
268  * @pg_in_transition : is device now in pg transition
269  * @pg_is_enabled    : is power gating enabled
270  *
271  * @intr_clear       : clear pending interrupts
272  * @intr_enable      : enable interrupts
273  * @intr_disable     : disable interrupts
274  * @synchronize_irq  : synchronize irqs
275  *
276  * @hbuf_free_slots  : query for write buffer empty slots
277  * @hbuf_is_ready    : query if write buffer is empty
278  * @hbuf_max_len     : query for write buffer max len
279  *
280  * @write            : write a message to FW
281  *
282  * @rdbuf_full_slots : query how many slots are filled
283  *
284  * @read_hdr         : get first 4 bytes (header)
285  * @read             : read a buffer from the FW
286  */
287 struct mei_hw_ops {
288 
289 	bool (*host_is_ready)(struct mei_device *dev);
290 
291 	bool (*hw_is_ready)(struct mei_device *dev);
292 	int (*hw_reset)(struct mei_device *dev, bool enable);
293 	int (*hw_start)(struct mei_device *dev);
294 	void (*hw_config)(struct mei_device *dev);
295 
296 	int (*fw_status)(struct mei_device *dev, struct mei_fw_status *fw_sts);
297 	enum mei_pg_state (*pg_state)(struct mei_device *dev);
298 	bool (*pg_in_transition)(struct mei_device *dev);
299 	bool (*pg_is_enabled)(struct mei_device *dev);
300 
301 	void (*intr_clear)(struct mei_device *dev);
302 	void (*intr_enable)(struct mei_device *dev);
303 	void (*intr_disable)(struct mei_device *dev);
304 	void (*synchronize_irq)(struct mei_device *dev);
305 
306 	int (*hbuf_free_slots)(struct mei_device *dev);
307 	bool (*hbuf_is_ready)(struct mei_device *dev);
308 	size_t (*hbuf_max_len)(const struct mei_device *dev);
309 	int (*write)(struct mei_device *dev,
310 		     struct mei_msg_hdr *hdr,
311 		     const unsigned char *buf);
312 
313 	int (*rdbuf_full_slots)(struct mei_device *dev);
314 
315 	u32 (*read_hdr)(const struct mei_device *dev);
316 	int (*read)(struct mei_device *dev,
317 		     unsigned char *buf, unsigned long len);
318 };
319 
320 /* MEI bus API*/
321 void mei_cl_bus_rescan(struct mei_device *bus);
322 void mei_cl_bus_rescan_work(struct work_struct *work);
323 void mei_cl_bus_dev_fixup(struct mei_cl_device *dev);
324 ssize_t __mei_cl_send(struct mei_cl *cl, u8 *buf, size_t length,
325 		      unsigned int mode);
326 ssize_t __mei_cl_recv(struct mei_cl *cl, u8 *buf, size_t length,
327 		      unsigned int mode);
328 bool mei_cl_bus_rx_event(struct mei_cl *cl);
329 bool mei_cl_bus_notify_event(struct mei_cl *cl);
330 void mei_cl_bus_remove_devices(struct mei_device *bus);
331 bool mei_cl_bus_module_get(struct mei_cl *cl);
332 void mei_cl_bus_module_put(struct mei_cl *cl);
333 int mei_cl_bus_init(void);
334 void mei_cl_bus_exit(void);
335 
336 /**
337  * enum mei_pg_event - power gating transition events
338  *
339  * @MEI_PG_EVENT_IDLE: the driver is not in power gating transition
340  * @MEI_PG_EVENT_WAIT: the driver is waiting for a pg event to complete
341  * @MEI_PG_EVENT_RECEIVED: the driver received pg event
342  * @MEI_PG_EVENT_INTR_WAIT: the driver is waiting for a pg event interrupt
343  * @MEI_PG_EVENT_INTR_RECEIVED: the driver received pg event interrupt
344  */
345 enum mei_pg_event {
346 	MEI_PG_EVENT_IDLE,
347 	MEI_PG_EVENT_WAIT,
348 	MEI_PG_EVENT_RECEIVED,
349 	MEI_PG_EVENT_INTR_WAIT,
350 	MEI_PG_EVENT_INTR_RECEIVED,
351 };
352 
353 /**
354  * enum mei_pg_state - device internal power gating state
355  *
356  * @MEI_PG_OFF: device is not power gated - it is active
357  * @MEI_PG_ON:  device is power gated - it is in lower power state
358  */
359 enum mei_pg_state {
360 	MEI_PG_OFF = 0,
361 	MEI_PG_ON =  1,
362 };
363 
364 const char *mei_pg_state_str(enum mei_pg_state state);
365 
366 /**
367  * struct mei_device -  MEI private device struct
368  *
369  * @dev         : device on a bus
370  * @cdev        : character device
371  * @minor       : minor number allocated for device
372  *
373  * @write_list  : write pending list
374  * @write_waiting_list : write completion list
375  * @ctrl_wr_list : pending control write list
376  * @ctrl_rd_list : pending control read list
377  *
378  * @file_list   : list of opened handles
379  * @open_handle_count: number of opened handles
380  *
381  * @device_lock : big device lock
382  * @timer_work  : MEI timer delayed work (timeouts)
383  *
384  * @recvd_hw_ready : hw ready message received flag
385  *
386  * @wait_hw_ready : wait queue for receive HW ready message form FW
387  * @wait_pg     : wait queue for receive PG message from FW
388  * @wait_hbm_start : wait queue for receive HBM start message from FW
389  *
390  * @reset_count : number of consecutive resets
391  * @dev_state   : device state
392  * @hbm_state   : state of host bus message protocol
393  * @init_clients_timer : HBM init handshake timeout
394  *
395  * @pg_event    : power gating event
396  * @pg_domain   : runtime PM domain
397  *
398  * @rd_msg_buf  : control messages buffer
399  * @rd_msg_hdr  : read message header storage
400  *
401  * @hbuf_depth  : depth of hardware host/write buffer is slots
402  * @hbuf_is_ready : query if the host host/write buffer is ready
403  *
404  * @version     : HBM protocol version in use
405  * @hbm_f_pg_supported  : hbm feature pgi protocol
406  * @hbm_f_dc_supported  : hbm feature dynamic clients
407  * @hbm_f_dot_supported : hbm feature disconnect on timeout
408  * @hbm_f_ev_supported  : hbm feature event notification
409  * @hbm_f_fa_supported  : hbm feature fixed address client
410  * @hbm_f_ie_supported  : hbm feature immediate reply to enum request
411  * @hbm_f_os_supported  : hbm feature support OS ver message
412  *
413  * @me_clients_rwsem: rw lock over me_clients list
414  * @me_clients  : list of FW clients
415  * @me_clients_map : FW clients bit map
416  * @host_clients_map : host clients id pool
417  *
418  * @allow_fixed_address: allow user space to connect a fixed client
419  * @override_fixed_address: force allow fixed address behavior
420  *
421  * @amthif_cmd_list : amthif list for cmd waiting
422  * @iamthif_cl  : amthif host client
423  * @iamthif_open_count : number of opened amthif connections
424  * @iamthif_stall_timer : timer to detect amthif hang
425  * @iamthif_state : amthif processor state
426  * @iamthif_canceled : current amthif command is canceled
427  *
428  * @reset_work  : work item for the device reset
429  * @bus_rescan_work : work item for the bus rescan
430  *
431  * @device_list : mei client bus list
432  * @cl_bus_lock : client bus list lock
433  *
434  * @dbgfs_dir   : debugfs mei root directory
435  *
436  * @ops:        : hw specific operations
437  * @hw          : hw specific data
438  */
439 struct mei_device {
440 	struct device *dev;
441 	struct cdev cdev;
442 	int minor;
443 
444 	struct list_head write_list;
445 	struct list_head write_waiting_list;
446 	struct list_head ctrl_wr_list;
447 	struct list_head ctrl_rd_list;
448 
449 	struct list_head file_list;
450 	long open_handle_count;
451 
452 	struct mutex device_lock;
453 	struct delayed_work timer_work;
454 
455 	bool recvd_hw_ready;
456 	/*
457 	 * waiting queue for receive message from FW
458 	 */
459 	wait_queue_head_t wait_hw_ready;
460 	wait_queue_head_t wait_pg;
461 	wait_queue_head_t wait_hbm_start;
462 
463 	/*
464 	 * mei device  states
465 	 */
466 	unsigned long reset_count;
467 	enum mei_dev_state dev_state;
468 	enum mei_hbm_state hbm_state;
469 	u16 init_clients_timer;
470 
471 	/*
472 	 * Power Gating support
473 	 */
474 	enum mei_pg_event pg_event;
475 #ifdef CONFIG_PM
476 	struct dev_pm_domain pg_domain;
477 #endif /* CONFIG_PM */
478 
479 	unsigned char rd_msg_buf[MEI_RD_MSG_BUF_SIZE];
480 	u32 rd_msg_hdr;
481 
482 	/* write buffer */
483 	u8 hbuf_depth;
484 	bool hbuf_is_ready;
485 
486 	struct hbm_version version;
487 	unsigned int hbm_f_pg_supported:1;
488 	unsigned int hbm_f_dc_supported:1;
489 	unsigned int hbm_f_dot_supported:1;
490 	unsigned int hbm_f_ev_supported:1;
491 	unsigned int hbm_f_fa_supported:1;
492 	unsigned int hbm_f_ie_supported:1;
493 	unsigned int hbm_f_os_supported:1;
494 
495 	struct rw_semaphore me_clients_rwsem;
496 	struct list_head me_clients;
497 	DECLARE_BITMAP(me_clients_map, MEI_CLIENTS_MAX);
498 	DECLARE_BITMAP(host_clients_map, MEI_CLIENTS_MAX);
499 
500 	bool allow_fixed_address;
501 	bool override_fixed_address;
502 
503 	/* amthif list for cmd waiting */
504 	struct list_head amthif_cmd_list;
505 	struct mei_cl iamthif_cl;
506 	long iamthif_open_count;
507 	u32 iamthif_stall_timer;
508 	enum iamthif_states iamthif_state;
509 	bool iamthif_canceled;
510 
511 	struct work_struct reset_work;
512 	struct work_struct bus_rescan_work;
513 
514 	/* List of bus devices */
515 	struct list_head device_list;
516 	struct mutex cl_bus_lock;
517 
518 #if IS_ENABLED(CONFIG_DEBUG_FS)
519 	struct dentry *dbgfs_dir;
520 #endif /* CONFIG_DEBUG_FS */
521 
522 
523 	const struct mei_hw_ops *ops;
524 	char hw[0] __aligned(sizeof(void *));
525 };
526 
527 static inline unsigned long mei_secs_to_jiffies(unsigned long sec)
528 {
529 	return msecs_to_jiffies(sec * MSEC_PER_SEC);
530 }
531 
532 /**
533  * mei_data2slots - get slots - number of (dwords) from a message length
534  *	+ size of the mei header
535  *
536  * @length: size of the messages in bytes
537  *
538  * Return: number of slots
539  */
540 static inline u32 mei_data2slots(size_t length)
541 {
542 	return DIV_ROUND_UP(sizeof(struct mei_msg_hdr) + length, 4);
543 }
544 
545 /**
546  * mei_slots2data - get data in slots - bytes from slots
547  *
548  * @slots: number of available slots
549  *
550  * Return: number of bytes in slots
551  */
552 static inline u32 mei_slots2data(int slots)
553 {
554 	return slots * 4;
555 }
556 
557 /*
558  * mei init function prototypes
559  */
560 void mei_device_init(struct mei_device *dev,
561 		     struct device *device,
562 		     const struct mei_hw_ops *hw_ops);
563 int mei_reset(struct mei_device *dev);
564 int mei_start(struct mei_device *dev);
565 int mei_restart(struct mei_device *dev);
566 void mei_stop(struct mei_device *dev);
567 void mei_cancel_work(struct mei_device *dev);
568 
569 /*
570  *  MEI interrupt functions prototype
571  */
572 
573 void mei_timer(struct work_struct *work);
574 void mei_schedule_stall_timer(struct mei_device *dev);
575 int mei_irq_read_handler(struct mei_device *dev,
576 			 struct list_head *cmpl_list, s32 *slots);
577 
578 int mei_irq_write_handler(struct mei_device *dev, struct list_head *cmpl_list);
579 void mei_irq_compl_handler(struct mei_device *dev, struct list_head *cmpl_list);
580 
581 /*
582  * AMTHIF - AMT Host Interface Functions
583  */
584 void mei_amthif_reset_params(struct mei_device *dev);
585 
586 int mei_amthif_host_init(struct mei_device *dev, struct mei_me_client *me_cl);
587 
588 unsigned int mei_amthif_poll(struct file *file, poll_table *wait);
589 
590 int mei_amthif_release(struct mei_device *dev, struct file *file);
591 
592 int mei_amthif_write(struct mei_cl *cl, struct mei_cl_cb *cb);
593 int mei_amthif_run_next_cmd(struct mei_device *dev);
594 int mei_amthif_irq_write(struct mei_cl *cl, struct mei_cl_cb *cb,
595 			 struct list_head *cmpl_list);
596 
597 void mei_amthif_complete(struct mei_cl *cl, struct mei_cl_cb *cb);
598 int mei_amthif_irq_read_msg(struct mei_cl *cl,
599 			    struct mei_msg_hdr *mei_hdr,
600 			    struct list_head *cmpl_list);
601 int mei_amthif_irq_read(struct mei_device *dev, s32 *slots);
602 
603 /*
604  * Register Access Function
605  */
606 
607 
608 static inline void mei_hw_config(struct mei_device *dev)
609 {
610 	dev->ops->hw_config(dev);
611 }
612 
613 static inline enum mei_pg_state mei_pg_state(struct mei_device *dev)
614 {
615 	return dev->ops->pg_state(dev);
616 }
617 
618 static inline bool mei_pg_in_transition(struct mei_device *dev)
619 {
620 	return dev->ops->pg_in_transition(dev);
621 }
622 
623 static inline bool mei_pg_is_enabled(struct mei_device *dev)
624 {
625 	return dev->ops->pg_is_enabled(dev);
626 }
627 
628 static inline int mei_hw_reset(struct mei_device *dev, bool enable)
629 {
630 	return dev->ops->hw_reset(dev, enable);
631 }
632 
633 static inline int mei_hw_start(struct mei_device *dev)
634 {
635 	return dev->ops->hw_start(dev);
636 }
637 
638 static inline void mei_clear_interrupts(struct mei_device *dev)
639 {
640 	dev->ops->intr_clear(dev);
641 }
642 
643 static inline void mei_enable_interrupts(struct mei_device *dev)
644 {
645 	dev->ops->intr_enable(dev);
646 }
647 
648 static inline void mei_disable_interrupts(struct mei_device *dev)
649 {
650 	dev->ops->intr_disable(dev);
651 }
652 
653 static inline void mei_synchronize_irq(struct mei_device *dev)
654 {
655 	dev->ops->synchronize_irq(dev);
656 }
657 
658 static inline bool mei_host_is_ready(struct mei_device *dev)
659 {
660 	return dev->ops->host_is_ready(dev);
661 }
662 static inline bool mei_hw_is_ready(struct mei_device *dev)
663 {
664 	return dev->ops->hw_is_ready(dev);
665 }
666 
667 static inline bool mei_hbuf_is_ready(struct mei_device *dev)
668 {
669 	return dev->ops->hbuf_is_ready(dev);
670 }
671 
672 static inline int mei_hbuf_empty_slots(struct mei_device *dev)
673 {
674 	return dev->ops->hbuf_free_slots(dev);
675 }
676 
677 static inline size_t mei_hbuf_max_len(const struct mei_device *dev)
678 {
679 	return dev->ops->hbuf_max_len(dev);
680 }
681 
682 static inline int mei_write_message(struct mei_device *dev,
683 				    struct mei_msg_hdr *hdr, const void *buf)
684 {
685 	return dev->ops->write(dev, hdr, buf);
686 }
687 
688 static inline u32 mei_read_hdr(const struct mei_device *dev)
689 {
690 	return dev->ops->read_hdr(dev);
691 }
692 
693 static inline void mei_read_slots(struct mei_device *dev,
694 		     unsigned char *buf, unsigned long len)
695 {
696 	dev->ops->read(dev, buf, len);
697 }
698 
699 static inline int mei_count_full_read_slots(struct mei_device *dev)
700 {
701 	return dev->ops->rdbuf_full_slots(dev);
702 }
703 
704 static inline int mei_fw_status(struct mei_device *dev,
705 				struct mei_fw_status *fw_status)
706 {
707 	return dev->ops->fw_status(dev, fw_status);
708 }
709 
710 bool mei_hbuf_acquire(struct mei_device *dev);
711 
712 bool mei_write_is_idle(struct mei_device *dev);
713 
714 void mei_irq_discard_msg(struct mei_device *dev, struct mei_msg_hdr *hdr);
715 
716 #if IS_ENABLED(CONFIG_DEBUG_FS)
717 int mei_dbgfs_register(struct mei_device *dev, const char *name);
718 void mei_dbgfs_deregister(struct mei_device *dev);
719 #else
720 static inline int mei_dbgfs_register(struct mei_device *dev, const char *name)
721 {
722 	return 0;
723 }
724 static inline void mei_dbgfs_deregister(struct mei_device *dev) {}
725 #endif /* CONFIG_DEBUG_FS */
726 
727 int mei_register(struct mei_device *dev, struct device *parent);
728 void mei_deregister(struct mei_device *dev);
729 
730 #define MEI_HDR_FMT "hdr:host=%02d me=%02d len=%d internal=%1d comp=%1d"
731 #define MEI_HDR_PRM(hdr)                  \
732 	(hdr)->host_addr, (hdr)->me_addr, \
733 	(hdr)->length, (hdr)->internal, (hdr)->msg_complete
734 
735 ssize_t mei_fw_status2str(struct mei_fw_status *fw_sts, char *buf, size_t len);
736 /**
737  * mei_fw_status_str - fetch and convert fw status registers to printable string
738  *
739  * @dev: the device structure
740  * @buf: string buffer at minimal size MEI_FW_STATUS_STR_SZ
741  * @len: buffer len must be >= MEI_FW_STATUS_STR_SZ
742  *
743  * Return: number of bytes written or < 0 on failure
744  */
745 static inline ssize_t mei_fw_status_str(struct mei_device *dev,
746 					char *buf, size_t len)
747 {
748 	struct mei_fw_status fw_status;
749 	int ret;
750 
751 	buf[0] = '\0';
752 
753 	ret = mei_fw_status(dev, &fw_status);
754 	if (ret)
755 		return ret;
756 
757 	ret = mei_fw_status2str(&fw_status, buf, MEI_FW_STATUS_STR_SZ);
758 
759 	return ret;
760 }
761 
762 
763 #endif
764