xref: /openbmc/linux/drivers/misc/mei/mei_dev.h (revision 0c874100)
1 /*
2  *
3  * Intel Management Engine Interface (Intel MEI) Linux driver
4  * Copyright (c) 2003-2018, 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 #define MEI_SLOT_SIZE             sizeof(u32)
30 #define MEI_RD_MSG_BUF_SIZE       (128 * MEI_SLOT_SIZE)
31 
32 /*
33  * Number of Maximum MEI Clients
34  */
35 #define MEI_CLIENTS_MAX 256
36 
37 /*
38  * maximum number of consecutive resets
39  */
40 #define MEI_MAX_CONSEC_RESET  3
41 
42 /*
43  * Number of File descriptors/handles
44  * that can be opened to the driver.
45  *
46  * Limit to 255: 256 Total Clients
47  * minus internal client for MEI Bus Messages
48  */
49 #define  MEI_MAX_OPEN_HANDLE_COUNT (MEI_CLIENTS_MAX - 1)
50 
51 /* File state */
52 enum file_state {
53 	MEI_FILE_UNINITIALIZED = 0,
54 	MEI_FILE_INITIALIZING,
55 	MEI_FILE_CONNECTING,
56 	MEI_FILE_CONNECTED,
57 	MEI_FILE_DISCONNECTING,
58 	MEI_FILE_DISCONNECT_REPLY,
59 	MEI_FILE_DISCONNECT_REQUIRED,
60 	MEI_FILE_DISCONNECTED,
61 };
62 
63 /* MEI device states */
64 enum mei_dev_state {
65 	MEI_DEV_INITIALIZING = 0,
66 	MEI_DEV_INIT_CLIENTS,
67 	MEI_DEV_ENABLED,
68 	MEI_DEV_RESETTING,
69 	MEI_DEV_DISABLED,
70 	MEI_DEV_POWER_DOWN,
71 	MEI_DEV_POWER_UP
72 };
73 
74 const char *mei_dev_state_str(int state);
75 
76 enum mei_file_transaction_states {
77 	MEI_IDLE,
78 	MEI_WRITING,
79 	MEI_WRITE_COMPLETE,
80 };
81 
82 /**
83  * enum mei_cb_file_ops  - file operation associated with the callback
84  * @MEI_FOP_READ:       read
85  * @MEI_FOP_WRITE:      write
86  * @MEI_FOP_CONNECT:    connect
87  * @MEI_FOP_DISCONNECT: disconnect
88  * @MEI_FOP_DISCONNECT_RSP: disconnect response
89  * @MEI_FOP_NOTIFY_START:   start notification
90  * @MEI_FOP_NOTIFY_STOP:    stop notification
91  */
92 enum mei_cb_file_ops {
93 	MEI_FOP_READ = 0,
94 	MEI_FOP_WRITE,
95 	MEI_FOP_CONNECT,
96 	MEI_FOP_DISCONNECT,
97 	MEI_FOP_DISCONNECT_RSP,
98 	MEI_FOP_NOTIFY_START,
99 	MEI_FOP_NOTIFY_STOP,
100 };
101 
102 /**
103  * enum mei_cl_io_mode - io mode between driver and fw
104  *
105  * @MEI_CL_IO_TX_BLOCKING: send is blocking
106  * @MEI_CL_IO_TX_INTERNAL: internal communication between driver and FW
107  *
108  * @MEI_CL_IO_RX_NONBLOCK: recv is non-blocking
109  */
110 enum mei_cl_io_mode {
111 	MEI_CL_IO_TX_BLOCKING = BIT(0),
112 	MEI_CL_IO_TX_INTERNAL = BIT(1),
113 
114 	MEI_CL_IO_RX_NONBLOCK = BIT(2),
115 };
116 
117 /*
118  * Intel MEI message data struct
119  */
120 struct mei_msg_data {
121 	size_t size;
122 	unsigned char *data;
123 };
124 
125 /* Maximum number of processed FW status registers */
126 #define MEI_FW_STATUS_MAX 6
127 /* Minimal  buffer for FW status string (8 bytes in dw + space or '\0') */
128 #define MEI_FW_STATUS_STR_SZ (MEI_FW_STATUS_MAX * (8 + 1))
129 
130 
131 /*
132  * struct mei_fw_status - storage of FW status data
133  *
134  * @count: number of actually available elements in array
135  * @status: FW status registers
136  */
137 struct mei_fw_status {
138 	int count;
139 	u32 status[MEI_FW_STATUS_MAX];
140 };
141 
142 /**
143  * struct mei_me_client - representation of me (fw) client
144  *
145  * @list: link in me client list
146  * @refcnt: struct reference count
147  * @props: client properties
148  * @client_id: me client id
149  * @tx_flow_ctrl_creds: flow control credits
150  * @connect_count: number connections to this client
151  * @bus_added: added to bus
152  */
153 struct mei_me_client {
154 	struct list_head list;
155 	struct kref refcnt;
156 	struct mei_client_properties props;
157 	u8 client_id;
158 	u8 tx_flow_ctrl_creds;
159 	u8 connect_count;
160 	u8 bus_added;
161 };
162 
163 
164 struct mei_cl;
165 
166 /**
167  * struct mei_cl_cb - file operation callback structure
168  *
169  * @list: link in callback queue
170  * @cl: file client who is running this operation
171  * @fop_type: file operation type
172  * @buf: buffer for data associated with the callback
173  * @buf_idx: last read index
174  * @fp: pointer to file structure
175  * @status: io status of the cb
176  * @internal: communication between driver and FW flag
177  * @blocking: transmission blocking mode
178  */
179 struct mei_cl_cb {
180 	struct list_head list;
181 	struct mei_cl *cl;
182 	enum mei_cb_file_ops fop_type;
183 	struct mei_msg_data buf;
184 	size_t buf_idx;
185 	const struct file *fp;
186 	int status;
187 	u32 internal:1;
188 	u32 blocking:1;
189 };
190 
191 /**
192  * struct mei_cl - me client host representation
193  *    carried in file->private_data
194  *
195  * @link: link in the clients list
196  * @dev: mei parent device
197  * @state: file operation state
198  * @tx_wait: wait queue for tx completion
199  * @rx_wait: wait queue for rx completion
200  * @wait:  wait queue for management operation
201  * @ev_wait: notification wait queue
202  * @ev_async: event async notification
203  * @status: connection status
204  * @me_cl: fw client connected
205  * @fp: file associated with client
206  * @host_client_id: host id
207  * @tx_flow_ctrl_creds: transmit flow credentials
208  * @rx_flow_ctrl_creds: receive flow credentials
209  * @timer_count:  watchdog timer for operation completion
210  * @notify_en: notification - enabled/disabled
211  * @notify_ev: pending notification event
212  * @tx_cb_queued: number of tx callbacks in queue
213  * @writing_state: state of the tx
214  * @rd_pending: pending read credits
215  * @rd_completed: completed read
216  *
217  * @cldev: device on the mei client bus
218  */
219 struct mei_cl {
220 	struct list_head link;
221 	struct mei_device *dev;
222 	enum file_state state;
223 	wait_queue_head_t tx_wait;
224 	wait_queue_head_t rx_wait;
225 	wait_queue_head_t wait;
226 	wait_queue_head_t ev_wait;
227 	struct fasync_struct *ev_async;
228 	int status;
229 	struct mei_me_client *me_cl;
230 	const struct file *fp;
231 	u8 host_client_id;
232 	u8 tx_flow_ctrl_creds;
233 	u8 rx_flow_ctrl_creds;
234 	u8 timer_count;
235 	u8 notify_en;
236 	u8 notify_ev;
237 	u8 tx_cb_queued;
238 	enum mei_file_transaction_states writing_state;
239 	struct list_head rd_pending;
240 	struct list_head rd_completed;
241 
242 	struct mei_cl_device *cldev;
243 };
244 
245 #define MEI_TX_QUEUE_LIMIT_DEFAULT 50
246 #define MEI_TX_QUEUE_LIMIT_MAX 255
247 #define MEI_TX_QUEUE_LIMIT_MIN 30
248 
249 /**
250  * struct mei_hw_ops - hw specific ops
251  *
252  * @host_is_ready    : query for host readiness
253  *
254  * @hw_is_ready      : query if hw is ready
255  * @hw_reset         : reset hw
256  * @hw_start         : start hw after reset
257  * @hw_config        : configure hw
258  *
259  * @fw_status        : get fw status registers
260  * @pg_state         : power gating state of the device
261  * @pg_in_transition : is device now in pg transition
262  * @pg_is_enabled    : is power gating enabled
263  *
264  * @intr_clear       : clear pending interrupts
265  * @intr_enable      : enable interrupts
266  * @intr_disable     : disable interrupts
267  * @synchronize_irq  : synchronize irqs
268  *
269  * @hbuf_free_slots  : query for write buffer empty slots
270  * @hbuf_is_ready    : query if write buffer is empty
271  * @hbuf_depth       : query for write buffer depth
272  *
273  * @write            : write a message to FW
274  *
275  * @rdbuf_full_slots : query how many slots are filled
276  *
277  * @read_hdr         : get first 4 bytes (header)
278  * @read             : read a buffer from the FW
279  */
280 struct mei_hw_ops {
281 
282 	bool (*host_is_ready)(struct mei_device *dev);
283 
284 	bool (*hw_is_ready)(struct mei_device *dev);
285 	int (*hw_reset)(struct mei_device *dev, bool enable);
286 	int (*hw_start)(struct mei_device *dev);
287 	void (*hw_config)(struct mei_device *dev);
288 
289 	int (*fw_status)(struct mei_device *dev, struct mei_fw_status *fw_sts);
290 	enum mei_pg_state (*pg_state)(struct mei_device *dev);
291 	bool (*pg_in_transition)(struct mei_device *dev);
292 	bool (*pg_is_enabled)(struct mei_device *dev);
293 
294 	void (*intr_clear)(struct mei_device *dev);
295 	void (*intr_enable)(struct mei_device *dev);
296 	void (*intr_disable)(struct mei_device *dev);
297 	void (*synchronize_irq)(struct mei_device *dev);
298 
299 	int (*hbuf_free_slots)(struct mei_device *dev);
300 	bool (*hbuf_is_ready)(struct mei_device *dev);
301 	u32 (*hbuf_depth)(const struct mei_device *dev);
302 	int (*write)(struct mei_device *dev,
303 		     const void *hdr, size_t hdr_len,
304 		     const void *data, size_t data_len);
305 
306 	int (*rdbuf_full_slots)(struct mei_device *dev);
307 
308 	u32 (*read_hdr)(const struct mei_device *dev);
309 	int (*read)(struct mei_device *dev,
310 		     unsigned char *buf, unsigned long len);
311 };
312 
313 /* MEI bus API*/
314 void mei_cl_bus_rescan_work(struct work_struct *work);
315 void mei_cl_bus_dev_fixup(struct mei_cl_device *dev);
316 ssize_t __mei_cl_send(struct mei_cl *cl, u8 *buf, size_t length,
317 		      unsigned int mode);
318 ssize_t __mei_cl_recv(struct mei_cl *cl, u8 *buf, size_t length,
319 		      unsigned int mode, unsigned long timeout);
320 bool mei_cl_bus_rx_event(struct mei_cl *cl);
321 bool mei_cl_bus_notify_event(struct mei_cl *cl);
322 void mei_cl_bus_remove_devices(struct mei_device *bus);
323 int mei_cl_bus_init(void);
324 void mei_cl_bus_exit(void);
325 
326 /**
327  * enum mei_pg_event - power gating transition events
328  *
329  * @MEI_PG_EVENT_IDLE: the driver is not in power gating transition
330  * @MEI_PG_EVENT_WAIT: the driver is waiting for a pg event to complete
331  * @MEI_PG_EVENT_RECEIVED: the driver received pg event
332  * @MEI_PG_EVENT_INTR_WAIT: the driver is waiting for a pg event interrupt
333  * @MEI_PG_EVENT_INTR_RECEIVED: the driver received pg event interrupt
334  */
335 enum mei_pg_event {
336 	MEI_PG_EVENT_IDLE,
337 	MEI_PG_EVENT_WAIT,
338 	MEI_PG_EVENT_RECEIVED,
339 	MEI_PG_EVENT_INTR_WAIT,
340 	MEI_PG_EVENT_INTR_RECEIVED,
341 };
342 
343 /**
344  * enum mei_pg_state - device internal power gating state
345  *
346  * @MEI_PG_OFF: device is not power gated - it is active
347  * @MEI_PG_ON:  device is power gated - it is in lower power state
348  */
349 enum mei_pg_state {
350 	MEI_PG_OFF = 0,
351 	MEI_PG_ON =  1,
352 };
353 
354 const char *mei_pg_state_str(enum mei_pg_state state);
355 
356 /**
357  * struct mei_fw_version - MEI FW version struct
358  *
359  * @platform: platform identifier
360  * @major: major version field
361  * @minor: minor version field
362  * @buildno: build number version field
363  * @hotfix: hotfix number version field
364  */
365 struct mei_fw_version {
366 	u8 platform;
367 	u8 major;
368 	u16 minor;
369 	u16 buildno;
370 	u16 hotfix;
371 };
372 
373 #define MEI_MAX_FW_VER_BLOCKS 3
374 
375 /**
376  * struct mei_device -  MEI private device struct
377  *
378  * @dev         : device on a bus
379  * @cdev        : character device
380  * @minor       : minor number allocated for device
381  *
382  * @write_list  : write pending list
383  * @write_waiting_list : write completion list
384  * @ctrl_wr_list : pending control write list
385  * @ctrl_rd_list : pending control read list
386  * @tx_queue_limit: tx queues per client linit
387  *
388  * @file_list   : list of opened handles
389  * @open_handle_count: number of opened handles
390  *
391  * @device_lock : big device lock
392  * @timer_work  : MEI timer delayed work (timeouts)
393  *
394  * @recvd_hw_ready : hw ready message received flag
395  *
396  * @wait_hw_ready : wait queue for receive HW ready message form FW
397  * @wait_pg     : wait queue for receive PG message from FW
398  * @wait_hbm_start : wait queue for receive HBM start message from FW
399  *
400  * @reset_count : number of consecutive resets
401  * @dev_state   : device state
402  * @hbm_state   : state of host bus message protocol
403  * @init_clients_timer : HBM init handshake timeout
404  *
405  * @pg_event    : power gating event
406  * @pg_domain   : runtime PM domain
407  *
408  * @rd_msg_buf  : control messages buffer
409  * @rd_msg_hdr  : read message header storage
410  *
411  * @hbuf_is_ready : query if the host host/write buffer is ready
412  *
413  * @version     : HBM protocol version in use
414  * @hbm_f_pg_supported  : hbm feature pgi protocol
415  * @hbm_f_dc_supported  : hbm feature dynamic clients
416  * @hbm_f_dot_supported : hbm feature disconnect on timeout
417  * @hbm_f_ev_supported  : hbm feature event notification
418  * @hbm_f_fa_supported  : hbm feature fixed address client
419  * @hbm_f_ie_supported  : hbm feature immediate reply to enum request
420  * @hbm_f_os_supported  : hbm feature support OS ver message
421  * @hbm_f_dr_supported  : hbm feature dma ring supported
422  *
423  * @fw_ver : FW versions
424  *
425  * @me_clients_rwsem: rw lock over me_clients list
426  * @me_clients  : list of FW clients
427  * @me_clients_map : FW clients bit map
428  * @host_clients_map : host clients id pool
429  *
430  * @allow_fixed_address: allow user space to connect a fixed client
431  * @override_fixed_address: force allow fixed address behavior
432  *
433  * @reset_work  : work item for the device reset
434  * @bus_rescan_work : work item for the bus rescan
435  *
436  * @device_list : mei client bus list
437  * @cl_bus_lock : client bus list lock
438  *
439  * @dbgfs_dir   : debugfs mei root directory
440  *
441  * @ops:        : hw specific operations
442  * @hw          : hw specific data
443  */
444 struct mei_device {
445 	struct device *dev;
446 	struct cdev cdev;
447 	int minor;
448 
449 	struct list_head write_list;
450 	struct list_head write_waiting_list;
451 	struct list_head ctrl_wr_list;
452 	struct list_head ctrl_rd_list;
453 	u8 tx_queue_limit;
454 
455 	struct list_head file_list;
456 	long open_handle_count;
457 
458 	struct mutex device_lock;
459 	struct delayed_work timer_work;
460 
461 	bool recvd_hw_ready;
462 	/*
463 	 * waiting queue for receive message from FW
464 	 */
465 	wait_queue_head_t wait_hw_ready;
466 	wait_queue_head_t wait_pg;
467 	wait_queue_head_t wait_hbm_start;
468 
469 	/*
470 	 * mei device  states
471 	 */
472 	unsigned long reset_count;
473 	enum mei_dev_state dev_state;
474 	enum mei_hbm_state hbm_state;
475 	u16 init_clients_timer;
476 
477 	/*
478 	 * Power Gating support
479 	 */
480 	enum mei_pg_event pg_event;
481 #ifdef CONFIG_PM
482 	struct dev_pm_domain pg_domain;
483 #endif /* CONFIG_PM */
484 
485 	unsigned char rd_msg_buf[MEI_RD_MSG_BUF_SIZE];
486 	u32 rd_msg_hdr;
487 
488 	/* write buffer */
489 	bool hbuf_is_ready;
490 
491 	struct hbm_version version;
492 	unsigned int hbm_f_pg_supported:1;
493 	unsigned int hbm_f_dc_supported:1;
494 	unsigned int hbm_f_dot_supported:1;
495 	unsigned int hbm_f_ev_supported:1;
496 	unsigned int hbm_f_fa_supported:1;
497 	unsigned int hbm_f_ie_supported:1;
498 	unsigned int hbm_f_os_supported:1;
499 	unsigned int hbm_f_dr_supported:1;
500 
501 	struct mei_fw_version fw_ver[MEI_MAX_FW_VER_BLOCKS];
502 
503 	struct rw_semaphore me_clients_rwsem;
504 	struct list_head me_clients;
505 	DECLARE_BITMAP(me_clients_map, MEI_CLIENTS_MAX);
506 	DECLARE_BITMAP(host_clients_map, MEI_CLIENTS_MAX);
507 
508 	bool allow_fixed_address;
509 	bool override_fixed_address;
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 from a message length
534  *
535  * @length: size of the messages in bytes
536  *
537  * Return: number of slots
538  */
539 static inline u32 mei_data2slots(size_t length)
540 {
541 	return DIV_ROUND_UP(length, MEI_SLOT_SIZE);
542 }
543 
544 /**
545  * mei_hbm2slots - get slots number from a hbm message length
546  *                 length + size of the mei message header
547  *
548  * @length: size of the messages in bytes
549  *
550  * Return: number of slots
551  */
552 static inline u32 mei_hbm2slots(size_t length)
553 {
554 	return DIV_ROUND_UP(sizeof(struct mei_msg_hdr) + length, MEI_SLOT_SIZE);
555 }
556 
557 /**
558  * mei_slots2data - get data in slots - bytes from slots
559  *
560  * @slots: number of available slots
561  *
562  * Return: number of bytes in slots
563  */
564 static inline u32 mei_slots2data(int slots)
565 {
566 	return slots * MEI_SLOT_SIZE;
567 }
568 
569 /*
570  * mei init function prototypes
571  */
572 void mei_device_init(struct mei_device *dev,
573 		     struct device *device,
574 		     const struct mei_hw_ops *hw_ops);
575 int mei_reset(struct mei_device *dev);
576 int mei_start(struct mei_device *dev);
577 int mei_restart(struct mei_device *dev);
578 void mei_stop(struct mei_device *dev);
579 void mei_cancel_work(struct mei_device *dev);
580 
581 /*
582  *  MEI interrupt functions prototype
583  */
584 
585 void mei_timer(struct work_struct *work);
586 void mei_schedule_stall_timer(struct mei_device *dev);
587 int mei_irq_read_handler(struct mei_device *dev,
588 			 struct list_head *cmpl_list, s32 *slots);
589 
590 int mei_irq_write_handler(struct mei_device *dev, struct list_head *cmpl_list);
591 void mei_irq_compl_handler(struct mei_device *dev, struct list_head *cmpl_list);
592 
593 /*
594  * Register Access Function
595  */
596 
597 
598 static inline void mei_hw_config(struct mei_device *dev)
599 {
600 	dev->ops->hw_config(dev);
601 }
602 
603 static inline enum mei_pg_state mei_pg_state(struct mei_device *dev)
604 {
605 	return dev->ops->pg_state(dev);
606 }
607 
608 static inline bool mei_pg_in_transition(struct mei_device *dev)
609 {
610 	return dev->ops->pg_in_transition(dev);
611 }
612 
613 static inline bool mei_pg_is_enabled(struct mei_device *dev)
614 {
615 	return dev->ops->pg_is_enabled(dev);
616 }
617 
618 static inline int mei_hw_reset(struct mei_device *dev, bool enable)
619 {
620 	return dev->ops->hw_reset(dev, enable);
621 }
622 
623 static inline int mei_hw_start(struct mei_device *dev)
624 {
625 	return dev->ops->hw_start(dev);
626 }
627 
628 static inline void mei_clear_interrupts(struct mei_device *dev)
629 {
630 	dev->ops->intr_clear(dev);
631 }
632 
633 static inline void mei_enable_interrupts(struct mei_device *dev)
634 {
635 	dev->ops->intr_enable(dev);
636 }
637 
638 static inline void mei_disable_interrupts(struct mei_device *dev)
639 {
640 	dev->ops->intr_disable(dev);
641 }
642 
643 static inline void mei_synchronize_irq(struct mei_device *dev)
644 {
645 	dev->ops->synchronize_irq(dev);
646 }
647 
648 static inline bool mei_host_is_ready(struct mei_device *dev)
649 {
650 	return dev->ops->host_is_ready(dev);
651 }
652 static inline bool mei_hw_is_ready(struct mei_device *dev)
653 {
654 	return dev->ops->hw_is_ready(dev);
655 }
656 
657 static inline bool mei_hbuf_is_ready(struct mei_device *dev)
658 {
659 	return dev->ops->hbuf_is_ready(dev);
660 }
661 
662 static inline int mei_hbuf_empty_slots(struct mei_device *dev)
663 {
664 	return dev->ops->hbuf_free_slots(dev);
665 }
666 
667 static inline u32 mei_hbuf_depth(const struct mei_device *dev)
668 {
669 	return dev->ops->hbuf_depth(dev);
670 }
671 
672 static inline int mei_write_message(struct mei_device *dev,
673 				    const void *hdr, size_t hdr_len,
674 				    const void *data, size_t data_len)
675 {
676 	return dev->ops->write(dev, hdr, hdr_len, data, data_len);
677 }
678 
679 static inline u32 mei_read_hdr(const struct mei_device *dev)
680 {
681 	return dev->ops->read_hdr(dev);
682 }
683 
684 static inline void mei_read_slots(struct mei_device *dev,
685 		     unsigned char *buf, unsigned long len)
686 {
687 	dev->ops->read(dev, buf, len);
688 }
689 
690 static inline int mei_count_full_read_slots(struct mei_device *dev)
691 {
692 	return dev->ops->rdbuf_full_slots(dev);
693 }
694 
695 static inline int mei_fw_status(struct mei_device *dev,
696 				struct mei_fw_status *fw_status)
697 {
698 	return dev->ops->fw_status(dev, fw_status);
699 }
700 
701 bool mei_hbuf_acquire(struct mei_device *dev);
702 
703 bool mei_write_is_idle(struct mei_device *dev);
704 
705 #if IS_ENABLED(CONFIG_DEBUG_FS)
706 int mei_dbgfs_register(struct mei_device *dev, const char *name);
707 void mei_dbgfs_deregister(struct mei_device *dev);
708 #else
709 static inline int mei_dbgfs_register(struct mei_device *dev, const char *name)
710 {
711 	return 0;
712 }
713 static inline void mei_dbgfs_deregister(struct mei_device *dev) {}
714 #endif /* CONFIG_DEBUG_FS */
715 
716 int mei_register(struct mei_device *dev, struct device *parent);
717 void mei_deregister(struct mei_device *dev);
718 
719 #define MEI_HDR_FMT "hdr:host=%02d me=%02d len=%d dma=%1d internal=%1d comp=%1d"
720 #define MEI_HDR_PRM(hdr)                  \
721 	(hdr)->host_addr, (hdr)->me_addr, \
722 	(hdr)->length, (hdr)->dma_ring, (hdr)->internal, (hdr)->msg_complete
723 
724 ssize_t mei_fw_status2str(struct mei_fw_status *fw_sts, char *buf, size_t len);
725 /**
726  * mei_fw_status_str - fetch and convert fw status registers to printable string
727  *
728  * @dev: the device structure
729  * @buf: string buffer at minimal size MEI_FW_STATUS_STR_SZ
730  * @len: buffer len must be >= MEI_FW_STATUS_STR_SZ
731  *
732  * Return: number of bytes written or < 0 on failure
733  */
734 static inline ssize_t mei_fw_status_str(struct mei_device *dev,
735 					char *buf, size_t len)
736 {
737 	struct mei_fw_status fw_status;
738 	int ret;
739 
740 	buf[0] = '\0';
741 
742 	ret = mei_fw_status(dev, &fw_status);
743 	if (ret)
744 		return ret;
745 
746 	ret = mei_fw_status2str(&fw_status, buf, MEI_FW_STATUS_STR_SZ);
747 
748 	return ret;
749 }
750 
751 
752 #endif
753