OpenCloudOS-Kernel/drivers/misc/mei/mei_dev.h

829 lines
21 KiB
C

/* SPDX-License-Identifier: GPL-2.0 */
/*
* Copyright (c) 2003-2019, Intel Corporation. All rights reserved.
* Intel Management Engine Interface (Intel MEI) Linux driver
*/
#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"
#define MEI_SLOT_SIZE sizeof(u32)
#define MEI_RD_MSG_BUF_SIZE (128 * MEI_SLOT_SIZE)
/*
* 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_UNINITIALIZED = 0,
MEI_FILE_INITIALIZING,
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_POWERING_DOWN,
MEI_DEV_POWER_DOWN,
MEI_DEV_POWER_UP
};
const char *mei_dev_state_str(int state);
enum mei_file_transaction_states {
MEI_IDLE,
MEI_WRITING,
MEI_WRITE_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
* @MEI_FOP_DMA_MAP: request client dma map
* @MEI_FOP_DMA_UNMAP: request client dma unmap
*/
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,
MEI_FOP_DMA_MAP,
MEI_FOP_DMA_UNMAP,
};
/**
* enum mei_cl_io_mode - io mode between driver and fw
*
* @MEI_CL_IO_TX_BLOCKING: send is blocking
* @MEI_CL_IO_TX_INTERNAL: internal communication between driver and FW
*
* @MEI_CL_IO_RX_NONBLOCK: recv is non-blocking
*/
enum mei_cl_io_mode {
MEI_CL_IO_TX_BLOCKING = BIT(0),
MEI_CL_IO_TX_INTERNAL = BIT(1),
MEI_CL_IO_RX_NONBLOCK = BIT(2),
};
/*
* Intel MEI message data struct
*/
struct mei_msg_data {
size_t size;
unsigned char *data;
};
struct mei_dma_data {
u8 buffer_id;
void *vaddr;
dma_addr_t daddr;
size_t size;
};
/**
* struct mei_dma_dscr - dma address descriptor
*
* @vaddr: dma buffer virtual address
* @daddr: dma buffer physical address
* @size : dma buffer size
*/
struct mei_dma_dscr {
void *vaddr;
dma_addr_t daddr;
size_t size;
};
/* 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
* @tx_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 tx_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
* @vtag: virtual tag
* @fp: pointer to file structure
* @status: io status of the cb
* @internal: communication between driver and FW flag
* @blocking: transmission blocking mode
*/
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;
u8 vtag;
const struct file *fp;
int status;
u32 internal:1;
u32 blocking:1;
};
/**
* struct mei_cl_vtag - file pointer to vtag mapping structure
*
* @list: link in map queue
* @fp: file pointer
* @vtag: corresponding vtag
* @pending_read: the read is pending on this file
*/
struct mei_cl_vtag {
struct list_head list;
const struct file *fp;
u8 vtag;
u8 pending_read: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
* @fp: file associated with client
* @host_client_id: host id
* @vtag_map: vtag map
* @tx_flow_ctrl_creds: transmit flow credentials
* @rx_flow_ctrl_creds: receive flow credentials
* @timer_count: watchdog timer for operation completion
* @notify_en: notification - enabled/disabled
* @notify_ev: pending notification event
* @tx_cb_queued: number of tx callbacks in queue
* @writing_state: state of the tx
* @rd_pending: pending read credits
* @rd_completed_lock: protects rd_completed queue
* @rd_completed: completed read
* @dma: dma settings
* @dma_mapped: dma buffer is currently mapped.
*
* @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;
const struct file *fp;
u8 host_client_id;
struct list_head vtag_map;
u8 tx_flow_ctrl_creds;
u8 rx_flow_ctrl_creds;
u8 timer_count;
u8 notify_en;
u8 notify_ev;
u8 tx_cb_queued;
enum mei_file_transaction_states writing_state;
struct list_head rd_pending;
spinlock_t rd_completed_lock; /* protects rd_completed queue */
struct list_head rd_completed;
struct mei_dma_data dma;
u8 dma_mapped;
struct mei_cl_device *cldev;
};
#define MEI_TX_QUEUE_LIMIT_DEFAULT 50
#define MEI_TX_QUEUE_LIMIT_MAX 255
#define MEI_TX_QUEUE_LIMIT_MIN 30
/**
* 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
* @trc_status : get trc status register
* @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
* @synchronize_irq : synchronize irqs
*
* @hbuf_free_slots : query for write buffer empty slots
* @hbuf_is_ready : query if write buffer is empty
* @hbuf_depth : query for write buffer depth
*
* @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);
int (*hw_config)(struct mei_device *dev);
int (*fw_status)(struct mei_device *dev, struct mei_fw_status *fw_sts);
int (*trc_status)(struct mei_device *dev, u32 *trc);
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);
void (*synchronize_irq)(struct mei_device *dev);
int (*hbuf_free_slots)(struct mei_device *dev);
bool (*hbuf_is_ready)(struct mei_device *dev);
u32 (*hbuf_depth)(const struct mei_device *dev);
int (*write)(struct mei_device *dev,
const void *hdr, size_t hdr_len,
const void *data, size_t data_len);
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_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, u8 vtag,
unsigned int mode);
ssize_t __mei_cl_recv(struct mei_cl *cl, u8 *buf, size_t length, u8 *vtag,
unsigned int mode, unsigned long timeout);
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_fw_version - MEI FW version struct
*
* @platform: platform identifier
* @major: major version field
* @minor: minor version field
* @buildno: build number version field
* @hotfix: hotfix number version field
*/
struct mei_fw_version {
u8 platform;
u8 major;
u16 minor;
u16 buildno;
u16 hotfix;
};
#define MEI_MAX_FW_VER_BLOCKS 3
/**
* 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
* @tx_queue_limit: tx queues per client linit
*
* @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
* @rd_msg_hdr_count : how many dwords were already read from header
*
* @hbuf_is_ready : query if the host host/write buffer is ready
* @dr_dscr: DMA ring descriptors: TX, RX, and CTRL
*
* @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
* @hbm_f_os_supported : hbm feature support OS ver message
* @hbm_f_dr_supported : hbm feature dma ring supported
* @hbm_f_vt_supported : hbm feature vtag supported
* @hbm_f_cap_supported : hbm feature capabilities message supported
* @hbm_f_cd_supported : hbm feature client dma supported
*
* @fw_ver : FW versions
*
* @fw_f_fw_ver_supported : fw feature: fw version supported
*
* @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
*
* @allow_fixed_address: allow user space to connect a fixed client
* @override_fixed_address: force allow fixed address behavior
*
* @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
*
* @kind : kind of mei device
*
* @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 list_head write_list;
struct list_head write_waiting_list;
struct list_head ctrl_wr_list;
struct list_head ctrl_rd_list;
u8 tx_queue_limit;
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[MEI_RD_MSG_BUF_SIZE];
int rd_msg_hdr_count;
/* write buffer */
bool hbuf_is_ready;
struct mei_dma_dscr dr_dscr[DMA_DSCR_NUM];
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;
unsigned int hbm_f_os_supported:1;
unsigned int hbm_f_dr_supported:1;
unsigned int hbm_f_vt_supported:1;
unsigned int hbm_f_cap_supported:1;
unsigned int hbm_f_cd_supported:1;
struct mei_fw_version fw_ver[MEI_MAX_FW_VER_BLOCKS];
unsigned int fw_f_fw_ver_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);
bool allow_fixed_address;
bool override_fixed_address;
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;
const char *kind;
#if IS_ENABLED(CONFIG_DEBUG_FS)
struct dentry *dbgfs_dir;
#endif /* CONFIG_DEBUG_FS */
const struct mei_hw_ops *ops;
char hw[] __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 from a message length
*
* @length: size of the messages in bytes
*
* Return: number of slots
*/
static inline u32 mei_data2slots(size_t length)
{
return DIV_ROUND_UP(length, MEI_SLOT_SIZE);
}
/**
* mei_hbm2slots - get slots number from a hbm message length
* length + size of the mei message header
*
* @length: size of the messages in bytes
*
* Return: number of slots
*/
static inline u32 mei_hbm2slots(size_t length)
{
return DIV_ROUND_UP(sizeof(struct mei_msg_hdr) + length, MEI_SLOT_SIZE);
}
/**
* 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 * MEI_SLOT_SIZE;
}
/*
* 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);
void mei_set_devstate(struct mei_device *dev, enum mei_dev_state state);
int mei_dmam_ring_alloc(struct mei_device *dev);
void mei_dmam_ring_free(struct mei_device *dev);
bool mei_dma_ring_is_allocated(struct mei_device *dev);
void mei_dma_ring_reset(struct mei_device *dev);
void mei_dma_ring_read(struct mei_device *dev, unsigned char *buf, u32 len);
void mei_dma_ring_write(struct mei_device *dev, unsigned char *buf, u32 len);
u32 mei_dma_ring_empty_slots(struct mei_device *dev);
/*
* MEI interrupt functions prototype
*/
void mei_timer(struct work_struct *work);
void mei_schedule_stall_timer(struct mei_device *dev);
int mei_irq_read_handler(struct mei_device *dev,
struct list_head *cmpl_list, s32 *slots);
int mei_irq_write_handler(struct mei_device *dev, struct list_head *cmpl_list);
void mei_irq_compl_handler(struct mei_device *dev, struct list_head *cmpl_list);
/*
* Register Access Function
*/
static inline int mei_hw_config(struct mei_device *dev)
{
return 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 void mei_synchronize_irq(struct mei_device *dev)
{
dev->ops->synchronize_irq(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 u32 mei_hbuf_depth(const struct mei_device *dev)
{
return dev->ops->hbuf_depth(dev);
}
static inline int mei_write_message(struct mei_device *dev,
const void *hdr, size_t hdr_len,
const void *data, size_t data_len)
{
return dev->ops->write(dev, hdr, hdr_len, data, data_len);
}
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_trc_status(struct mei_device *dev, u32 *trc)
{
if (dev->ops->trc_status)
return dev->ops->trc_status(dev, trc);
return -EOPNOTSUPP;
}
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)
void mei_dbgfs_register(struct mei_device *dev, const char *name);
void mei_dbgfs_deregister(struct mei_device *dev);
#else
static inline void mei_dbgfs_register(struct mei_device *dev, const char *name) {}
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 dma=%1d ext=%1d internal=%1d comp=%1d"
#define MEI_HDR_PRM(hdr) \
(hdr)->host_addr, (hdr)->me_addr, \
(hdr)->length, (hdr)->dma_ring, (hdr)->extended, \
(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