drivers/misc/mei/mei_dev.h

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