v4.19.13 snapshot.
diff --git a/drivers/misc/mei/mei_dev.h b/drivers/misc/mei/mei_dev.h
new file mode 100644
index 0000000..377397e
--- /dev/null
+++ b/drivers/misc/mei/mei_dev.h
@@ -0,0 +1,752 @@
+/*
+ *
+ * Intel Management Engine Interface (Intel MEI) Linux driver
+ * Copyright (c) 2003-2018, 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"
+
+#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_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
+ */
+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,
+};
+
+/**
+ * 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;
+};
+
+/* 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
+ * @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;
+ const struct file *fp;
+ int status;
+ u32 internal:1;
+ u32 blocking: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
+ * @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: 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;
+ const struct file *fp;
+ u8 host_client_id;
+ 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;
+ struct list_head rd_completed;
+
+ 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
+ * @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);
+ 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);
+ 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,
+ unsigned int mode);
+ssize_t __mei_cl_recv(struct mei_cl *cl, u8 *buf, size_t length,
+ 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
+ *
+ * @hbuf_is_ready : query if the host host/write buffer is ready
+ *
+ * @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
+ *
+ * @fw_ver : FW versions
+ *
+ * @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
+ *
+ * @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;
+
+ /* write buffer */
+ bool hbuf_is_ready;
+
+ 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;
+
+ struct mei_fw_version fw_ver[MEI_MAX_FW_VER_BLOCKS];
+
+ 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;
+
+#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 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);
+
+/*
+ * 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 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 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_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 dma=%1d internal=%1d comp=%1d"
+#define MEI_HDR_PRM(hdr) \
+ (hdr)->host_addr, (hdr)->me_addr, \
+ (hdr)->length, (hdr)->dma_ring, (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