// SPDX-License-Identifier: GPL-2.0
/*
* Copyright (c) 2003-2022, Intel Corporation. All rights reserved.
* Intel Management Engine Interface (Intel MEI) Linux driver
*/
#include <linux/module.h>
#include <linux/moduleparam.h>
#include <linux/kernel.h>
#include <linux/device.h>
#include <linux/slab.h>
#include <linux/fs.h>
#include <linux/errno.h>
#include <linux/types.h>
#include <linux/fcntl.h>
#include <linux/poll.h>
#include <linux/init.h>
#include <linux/ioctl.h>
#include <linux/cdev.h>
#include <linux/sched/signal.h>
#include <linux/compat.h>
#include <linux/jiffies.h>
#include <linux/interrupt.h>
#include <linux/mei.h>
#include "mei_dev.h"
#include "client.h"
static const struct class mei_class = {
.name = "mei",
};
static dev_t mei_devt;
#define MEI_MAX_DEVS MINORMASK
static DEFINE_MUTEX(mei_minor_lock);
static DEFINE_IDR(mei_idr);
/**
* mei_open - the open function
*
* @inode: pointer to inode structure
* @file: pointer to file structure
*
* Return: 0 on success, <0 on error
*/
static int mei_open(struct inode *inode, struct file *file)
{
struct mei_device *dev;
struct mei_cl *cl;
int err;
dev = container_of(inode->i_cdev, struct mei_device, cdev);
mutex_lock(&dev->device_lock);
if (dev->dev_state != MEI_DEV_ENABLED) {
dev_dbg(dev->dev, "dev_state != MEI_ENABLED dev_state = %s\n",
mei_dev_state_str(dev->dev_state));
err = -ENODEV;
goto err_unlock;
}
cl = mei_cl_alloc_linked(dev);
if (IS_ERR(cl)) {
err = PTR_ERR(cl);
goto err_unlock;
}
cl->fp = file;
file->private_data = cl;
mutex_unlock(&dev->device_lock);
return nonseekable_open(inode, file);
err_unlock:
mutex_unlock(&dev->device_lock);
return err;
}
/**
* mei_cl_vtag_remove_by_fp - remove vtag that corresponds to fp from list
*
* @cl: host client
* @fp: pointer to file structure
*
*/
static void mei_cl_vtag_remove_by_fp(const struct mei_cl *cl,
const struct file *fp)
{
struct mei_cl_vtag *vtag_l, *next;
list_for_each_entry_safe(vtag_l, next, &cl->vtag_map, list) {
if (vtag_l->fp == fp) {
list_del(&vtag_l->list);
kfree(vtag_l);
return;
}
}
}
/**
* mei_release - the release function
*
* @inode: pointer to inode structure
* @file: pointer to file structure
*
* Return: 0 on success, <0 on error
*/
static int mei_release(struct inode *inode, struct file *file)
{
struct mei_cl *cl = file->private_data;
struct mei_device *dev;
int rets;
if (WARN_ON(!cl || !cl->dev))
return -ENODEV;
dev = cl->dev;
mutex_lock(&dev->device_lock);
mei_cl_vtag_remove_by_fp(cl, file);
if (!list_empty(&cl->vtag_map)) {
cl_dbg(dev, cl, "not the last vtag\n");
mei_cl_flush_queues(cl, file);
rets = 0;
goto out;
}
rets = mei_cl_disconnect(cl);
/*
* Check again: This is necessary since disconnect releases the lock
* and another client can connect in the meantime.
*/
if (!list_empty(&cl->vtag_map)) {
cl_dbg(dev, cl, "not the last vtag after disconnect\n");
mei_cl_flush_queues(cl, file);
goto out;
}
mei_cl_flush_queues(cl, NULL);
cl_dbg(dev, cl, "removing\n");
mei_cl_unlink(cl);
kfree(cl);
out:
file->private_data = NULL;
mutex_unlock(&dev->device_lock);
return rets;
}
/**
* mei_read - the read function.
*
* @file: pointer to file structure
* @ubuf: pointer to user buffer
* @length: buffer length
* @offset: data offset in buffer
*
* Return: >=0 data length on success , <0 on error
*/
static ssize_t mei_read(struct file *file, char __user *ubuf,
size_t length, loff_t *offset)
{
struct mei_cl *cl = file->private_data;
struct mei_device *dev;
struct mei_cl_cb *cb = NULL;
bool nonblock = !!(file->f_flags & O_NONBLOCK);
ssize_t rets;
if (WARN_ON(!cl || !cl->dev))
return -ENODEV;
dev = cl->dev;
mutex_lock(&dev->device_lock);
if (dev->dev_state != MEI_DEV_ENABLED) {
rets = -ENODEV;
goto out;
}
if (length == 0) {
rets = 0;
goto out;
}
if (ubuf == NULL) {
rets = -EMSGSIZE;
goto out;
}
cb = mei_cl_read_cb(cl, file);
if (cb)
goto copy_buffer;
if (*offset > 0)
*offset = 0;
rets = mei_cl_read_start(cl, length, file);
if (rets && rets != -EBUSY) {
cl_dbg(dev, cl, "mei start read failure status = %zd\n", rets);
goto out;
}
if (nonblock) {
rets = -EAGAIN;
goto out;
}
mutex_unlock(&dev->device_lock);
if (wait_event_interruptible(cl->rx_wait,
mei_cl_read_cb(cl, file) ||
!mei_cl_is_connected(cl))) {
if (signal_pending(current))
return -EINTR;
return -ERESTARTSYS;
}
mutex_lock(&dev->device_lock);
if (!mei_cl_is_connected(cl)) {
rets = -ENODEV;
goto out;
}
cb = mei_cl_read_cb(cl, file);
if (!cb) {
rets = 0;
goto out;
}
copy_buffer:
/* now copy the data to user space */
if (cb->status) {
rets = cb->status;
cl_dbg(dev, cl, "read operation failed %zd\n", rets);
goto free;
}
cl_dbg(dev, cl, "buf.size = %zu buf.idx = %zu offset = %lld\n",
cb->buf.size, cb->buf_idx, *offset);
if (*offset >= cb->buf_idx) {
rets = 0;
goto free;
}
/* length is being truncated to PAGE_SIZE,
* however buf_idx may point beyond that */
length = min_t(size_t, length, cb->buf_idx - *offset);
if (copy_to_user(ubuf, cb->buf.data + *offset, length)) {
dev_dbg(dev->dev, "failed to copy data to userland\n");
rets = -EFAULT;
goto free;
}
rets = length;
*offset += length;
/* not all data was read, keep the cb */
if (*offset < cb->buf_idx)
goto out;
free:
mei_cl_del_rd_completed(cl, cb);
*offset = 0;
out:
cl_dbg(dev, cl, "end mei read rets = %zd\n", rets);
mutex_unlock(&dev->device_lock);
return rets;
}
/**
* mei_cl_vtag_by_fp - obtain the vtag by file pointer
*
* @cl: host client
* @fp: pointer to file structure
*
* Return: vtag value on success, otherwise 0
*/
static u8 mei_cl_vtag_by_fp(const struct mei_cl *cl, const struct file *fp)
{
struct mei_cl_vtag *cl_vtag;
if (!fp)
return 0;
list_for_each_entry(cl_vtag, &cl->vtag_map, list)
if (cl_vtag->fp == fp)
return cl_vtag->vtag;
return 0;
}
/**
* mei_write - the write function.
*
* @file: pointer to file structure
* @ubuf: pointer to user buffer
* @length: buffer length
* @offset: data offset in buffer
*
* Return: >=0 data length on success , <0 on error
*/
static ssize_t mei_write(struct file *file, const char __user *ubuf,
size_t length, loff_t *offset)
{
struct mei_cl *cl = file->private_data;
struct mei_cl_cb *cb;
struct mei_device *dev;
ssize_t rets;
if (WARN_ON(!cl || !cl->dev))
return -ENODEV;
dev = cl->dev;
mutex_lock(&dev->device_lock);
if (dev->dev_state != MEI_DEV_ENABLED) {
rets = -ENODEV;
goto out;
}
if (!mei_cl_is_connected(cl)) {
cl_dbg(dev, cl, "is not connected");
rets = -ENODEV;
goto out;
}
if (!mei_me_cl_is_active(cl->me_cl)) {
rets = -ENOTTY;
goto out;
}
if (length > mei_cl_mtu(cl)) {
rets = -EFBIG;
goto out;
}
if (length == 0) {
rets = 0;
goto out;
}
while (cl->tx_cb_queued >= dev->tx_queue_limit) {
if (file->f_flags & O_NONBLOCK) {
rets = -EAGAIN;
goto out;
}
mutex_unlock(&dev->device_lock);
rets = wait_event_interruptible(cl->tx_wait,
cl->writing_state == MEI_WRITE_COMPLETE ||
(!mei_cl_is_connected(cl)));
mutex_lock(&dev->device_lock);
if (rets) {
if (signal_pending(current))
rets = -EINTR;
goto out;
}
if (!mei_cl_is_connected(cl)) {
rets = -ENODEV;
goto out;
}
}
cb = mei_cl_alloc_cb(cl, length, MEI_FOP_WRITE, file);
if (!cb) {
rets = -ENOMEM;
goto out;
}
cb->vtag = mei_cl_vtag_by_fp(cl, file);
rets = copy_from_user(cb->buf.data, ubuf, length);
if (rets) {
dev_dbg(dev->dev, "failed to copy data from userland\n");
rets = -EFAULT;
mei_io_cb_free(cb);
goto out;
}
rets = mei_cl_write(cl, cb, MAX_SCHEDULE_TIMEOUT);
out:
mutex_unlock(&dev->device_lock);
return rets;
}
/**
* mei_ioctl_connect_client - the connect to fw client IOCTL function
*
* @file: private data of the file object
* @in_client_uuid: requested UUID for connection
* @client: IOCTL connect data, output parameters
*
* Locking: called under "dev->device_lock" lock
*
* Return: 0 on success, <0 on failure.
*/
static int mei_ioctl_connect_client(struct file *file,
const uuid_le *in_client_uuid,
struct mei_client *client)
{
struct mei_device *dev;
struct mei_me_client *me_cl;
struct mei_cl *cl;
int rets;
cl = file->private_data;
dev = cl->dev;
if (cl->state != MEI_FILE_INITIALIZING &&
cl->state != MEI_FILE_DISCONNECTED)
return -EBUSY;
/* find ME client we're trying to connect to */
me_cl = mei_me_cl_by_uuid(dev, in_client_uuid);
if (!me_cl) {
dev_dbg(dev->dev, "Cannot connect to FW Client UUID = %pUl\n",
in_client_uuid);
rets = -ENOTTY;
goto end;
}
if (me_cl->props.fixed_address) {
bool forbidden = dev->override_fixed_address ?
!dev->allow_fixed_address : !dev->hbm_f_fa_supported;
if (forbidden) {
dev_dbg(dev->dev, "Connection forbidden to FW Client UUID = %pUl\n",
in_client_uuid);
rets = -ENOTTY;
goto end;
}
}
dev_dbg(dev->dev, "Connect to FW Client ID = %d\n",
me_cl->client_id);
dev_dbg(dev->dev, "FW Client - Protocol Version = %d\n",
me_cl->props.protocol_version);
dev_dbg(dev->dev, "FW Client - Max Msg Len = %d\n",
me_cl->props.max_msg_length);
/* prepare the output buffer */
client->max_msg_length = me_cl->props.max_msg_length;
client->protocol_version = me_cl->props.protocol_version;
dev_dbg(dev->dev, "Can connect?\n");
rets = mei_cl_connect(cl, me_cl, file);
end:
mei_me_cl_put(me_cl);
return rets;
}
/**
* mei_vt_support_check - check if client support vtags
*
* @dev: mei_device
* @uuid: client UUID
*
* Locking: called under "dev->device_lock" lock
*
* Return:
* 0 - supported
* -ENOTTY - no such client
* -EOPNOTSUPP - vtags are not supported by client
*/
static int mei_vt_support_check(struct mei_device *dev, const uuid_le *uuid)
{
struct mei_me_client *me_cl;
int ret;
if (!dev->hbm_f_vt_supported)
return -EOPNOTSUPP;
me_cl = mei_me_cl_by_uuid(dev, uuid);
if (!me_cl) {
dev_dbg(dev->dev, "Cannot connect to FW Client UUID = %pUl\n",
uuid);
return -ENOTTY;
}
ret = me_cl->props.vt_supported ? 0 : -EOPNOTSUPP;
mei_me_cl_put(me_cl);
return ret;
}
/**
* mei_ioctl_connect_vtag - connect to fw client with vtag IOCTL function
*
* @file: private data of the file object
* @in_client_uuid: requested UUID for connection
* @client: IOCTL connect data, output parameters
* @vtag: vm tag
*
* Locking: called under "dev->device_lock" lock
*
* Return: 0 on success, <0 on failure.
*/
static int mei_ioctl_connect_vtag(struct file *file,
const uuid_le *in_client_uuid,
struct mei_client *client,
u8 vtag)
{
struct mei_device *dev;
struct mei_cl *cl;
struct mei_cl *pos;
struct mei_cl_vtag *cl_vtag;
cl = file->private_data;
dev = cl->dev;
dev_dbg(dev->dev, "FW Client %pUl vtag %d\n", in_client_uuid, vtag);
switch (cl->state) {
case MEI_FILE_DISCONNECTED:
if (mei_cl_vtag_by_fp(cl, file) != vtag) {
dev_err(dev->dev, "reconnect with different vtag\n");
return -EINVAL;
}
break;
case MEI_FILE_INITIALIZING:
/* malicious connect from another thread may push vtag */
if (!IS_ERR(mei_cl_fp_by_vtag(cl, vtag))) {
dev_err(dev->dev, "vtag already filled\n");
return -EINVAL;
}
list_for_each_entry(pos, &dev->file_list, link) {
if (pos == cl)
continue;
if (!pos->me_cl)
continue;
/* only search for same UUID */
if (uuid_le_cmp(*mei_cl_uuid(pos), *in_client_uuid))
continue;
/* if tag already exist try another fp */
if (!IS_ERR(mei_cl_fp_by_vtag(pos, vtag)))
continue;
/* replace cl with acquired one */
dev_dbg(dev->dev, "replacing with existing cl\n");
mei_cl_unlink(cl);
kfree(cl);
file->private_data = pos;
cl = pos;
break;
}
cl_vtag = mei_cl_vtag_alloc(file, vtag);
if (IS_ERR(cl_vtag))
return -ENOMEM;
list_add_tail(&cl_vtag->list, &cl->vtag_map);
break;
default:
return -EBUSY;
}
while (cl->state != MEI_FILE_INITIALIZING &&
cl->state != MEI_FILE_DISCONNECTED &&
cl->state != MEI_FILE_CONNECTED) {
mutex_unlock(&dev->device_lock);
wait_event_timeout(cl->wait,
(cl->state == MEI_FILE_CONNECTED ||
cl->state == MEI_FILE_DISCONNECTED ||
cl->state == MEI_FILE_DISCONNECT_REQUIRED ||
cl->state == MEI_FILE_DISCONNECT_REPLY),
dev->timeouts.cl_connect);
mutex_lock(&dev->device_lock);
}
if (!mei_cl_is_connected(cl))
return mei_ioctl_connect_client(file, in_client_uuid, client);
client->max_msg_length = cl->me_cl->props.max_msg_length;
client->protocol_version = cl->me_cl->props.protocol_version;
return 0;
}
/**
* mei_ioctl_client_notify_request - propagate event notification
* request to client
*
* @file: pointer to file structure
* @request: 0 - disable, 1 - enable
*
* Return: 0 on success , <0 on error
*/
static int mei_ioctl_client_notify_request(const struct file *file, u32 request)
{
struct mei_cl *cl = file->private_data;
if (request != MEI_HBM_NOTIFICATION_START &&
request != MEI_HBM_NOTIFICATION_STOP)
return -EINVAL;
return mei_cl_notify_request(cl, file, (u8)request);
}
/**
* mei_ioctl_client_notify_get - wait for notification request
*
* @file: pointer to file structure
* @notify_get: 0 - disable, 1 - enable
*
* Return: 0 on success , <0 on error
*/
static int mei_ioctl_client_notify_get(const struct file *file, u32 *notify_get)
{
struct mei_cl *cl = file->private_data;
bool notify_ev;
bool block = (file->f_flags & O_NONBLOCK) == 0;
int rets;
rets = mei_cl_notify_get(cl, block, ¬ify_ev);
if (rets)
return rets;
*notify_get = notify_ev ? 1 : 0;
return 0;
}
/**
* mei_ioctl - the IOCTL function
*
* @file: pointer to file structure
* @cmd: ioctl command
* @data: pointer to mei message structure
*
* Return: 0 on success , <0 on error
*/
static long mei_ioctl(struct file *file, unsigned int cmd, unsigned long data)
{
struct mei_device *dev;
struct mei_cl *cl = file->private_data;
struct mei_connect_client_data conn;
struct mei_connect_client_data_vtag conn_vtag;
const uuid_le *cl_uuid;
struct mei_client *props;
u8 vtag;
u32 notify_get, notify_req;
int rets;
if (WARN_ON(!cl || !cl->dev))
return -ENODEV;
dev = cl->dev;
dev_dbg(dev->dev, "IOCTL cmd = 0x%x", cmd);
mutex_lock(&dev->device_lock);
if (dev->dev_state != MEI_DEV_ENABLED) {
rets = -ENODEV;
goto out;
}
switch (cmd) {
case IOCTL_MEI_CONNECT_CLIENT:
dev_dbg(dev->dev, ": IOCTL_MEI_CONNECT_CLIENT.\n");
if (copy_from_user(&conn, (char __user *)data, sizeof(conn))) {
dev_dbg(dev->dev, "failed to copy data from userland\n");
rets = -EFAULT;
goto out;
}
cl_uuid = &conn.in_client_uuid;
props = &conn.out_client_properties;
vtag = 0;
rets = mei_vt_support_check(dev, cl_uuid);
if (rets == -ENOTTY)
goto out;
if (!rets)
rets = mei_ioctl_connect_vtag(file, cl_uuid, props,
vtag);
else
rets = mei_ioctl_connect_client(file, cl_uuid, props);
if (rets)
goto out;
/* if all is ok, copying the data back to user. */
if (copy_to_user((char __user *)data, &conn, sizeof(conn))) {
dev_dbg(dev->dev, "failed to copy data to userland\n");
rets = -EFAULT;
goto out;
}
break;
case IOCTL_MEI_CONNECT_CLIENT_VTAG:
dev_dbg(dev->dev, "IOCTL_MEI_CONNECT_CLIENT_VTAG\n");
if (copy_from_user(&conn_vtag, (char __user *)data,
sizeof(conn_vtag))) {
dev_dbg(dev->dev, "failed to copy data from userland\n");
rets = -EFAULT;
goto out;
}
cl_uuid = &conn_vtag.connect.in_client_uuid;
props = &conn_vtag.out_client_properties;
vtag = conn_vtag.connect.vtag;
rets = mei_vt_support_check(dev, cl_uuid);
if (rets == -EOPNOTSUPP)
dev_dbg(dev->dev, "FW Client %pUl does not support vtags\n",
cl_uuid);
if (rets)
goto out;
if (!vtag) {
dev_dbg(dev->dev, "vtag can't be zero\n");
rets = -EINVAL;
goto out;
}
rets = mei_ioctl_connect_vtag(file, cl_uuid, props, vtag);
if (rets)
goto out;
/* if all is ok, copying the data back to user. */
if (copy_to_user((char __user *)data, &conn_vtag,
sizeof(conn_vtag))) {
dev_dbg(dev->dev, "failed to copy data to userland\n");
rets = -EFAULT;
goto out;
}
break;
case IOCTL_MEI_NOTIFY_SET:
dev_dbg(dev->dev, ": IOCTL_MEI_NOTIFY_SET.\n");
if (copy_from_user(¬ify_req,
(char __user *)data, sizeof(notify_req))) {
dev_dbg(dev->dev, "failed to copy data from userland\n");
rets = -EFAULT;
goto out;
}
rets = mei_ioctl_client_notify_request(file, notify_req);
break;
case IOCTL_MEI_NOTIFY_GET:
dev_dbg(dev->dev, ": IOCTL_MEI_NOTIFY_GET.\n");
rets = mei_ioctl_client_notify_get(file, ¬ify_get);
if (rets)
goto out;
dev_dbg(dev->dev, "copy connect data to user\n");
if (copy_to_user((char __user *)data,
¬ify_get, sizeof(notify_get))) {
dev_dbg(dev->dev, "failed to copy data to userland\n");
rets = -EFAULT;
goto out;
}
break;
default:
rets = -ENOIOCTLCMD;
}
out:
mutex_unlock(&dev->device_lock);
return rets;
}
/**
* mei_poll - the poll function
*
* @file: pointer to file structure
* @wait: pointer to poll_table structure
*
* Return: poll mask
*/
static __poll_t mei_poll(struct file *file, poll_table *wait)
{
__poll_t req_events = poll_requested_events(wait);
struct mei_cl *cl = file->private_data;
struct mei_device *dev;
__poll_t mask = 0;
bool notify_en;
if (WARN_ON(!cl || !cl->dev))
return EPOLLERR;
dev = cl->dev;
mutex_lock(&dev->device_lock);
notify_en = cl->notify_en && (req_events & EPOLLPRI);
if (dev->dev_state != MEI_DEV_ENABLED ||
!mei_cl_is_connected(cl)) {
mask = EPOLLERR;
goto out;
}
if (notify_en) {
poll_wait(file, &cl->ev_wait, wait);
if (cl->notify_ev)
mask |= EPOLLPRI;
}
if (req_events & (EPOLLIN | EPOLLRDNORM)) {
poll_wait(file, &cl->rx_wait, wait);
if (mei_cl_read_cb(cl, file))
mask |= EPOLLIN | EPOLLRDNORM;
else
mei_cl_read_start(cl, mei_cl_mtu(cl), file);
}
if (req_events & (EPOLLOUT | EPOLLWRNORM)) {
poll_wait(file, &cl->tx_wait, wait);
if (cl->tx_cb_queued < dev->tx_queue_limit)
mask |= EPOLLOUT | EPOLLWRNORM;
}
out:
mutex_unlock(&dev->device_lock);
return mask;
}
/**
* mei_cl_is_write_queued - check if the client has pending writes.
*
* @cl: writing host client
*
* Return: true if client is writing, false otherwise.
*/
static bool mei_cl_is_write_queued(struct mei_cl *cl)
{
struct mei_device *dev = cl->dev;
struct mei_cl_cb *cb;
list_for_each_entry(cb, &dev->write_list, list)
if (cb->cl == cl)
return true;
list_for_each_entry(cb, &dev->write_waiting_list, list)
if (cb->cl == cl)
return true;
return false;
}
/**
* mei_fsync - the fsync handler
*
* @fp: pointer to file structure
* @start: unused
* @end: unused
* @datasync: unused
*
* Return: 0 on success, -ENODEV if client is not connected
*/
static int mei_fsync(struct file *fp, loff_t start, loff_t end, int datasync)
{
struct mei_cl *cl = fp->private_data;
struct mei_device *dev;
int rets;
if (WARN_ON(!cl || !cl->dev))
return -ENODEV;
dev = cl->dev;
mutex_lock(&dev->device_lock);
if (dev->dev_state != MEI_DEV_ENABLED || !mei_cl_is_connected(cl)) {
rets = -ENODEV;
goto out;
}
while (mei_cl_is_write_queued(cl)) {
mutex_unlock(&dev->device_lock);
rets = wait_event_interruptible(cl->tx_wait,
cl->writing_state == MEI_WRITE_COMPLETE ||
!mei_cl_is_connected(cl));
mutex_lock(&dev->device_lock);
if (rets) {
if (signal_pending(current))
rets = -EINTR;
goto out;
}
if (!mei_cl_is_connected(cl)) {
rets = -ENODEV;
goto out;
}
}
rets = 0;
out:
mutex_unlock(&dev->device_lock);
return rets;
}
/**
* mei_fasync - asynchronous io support
*
* @fd: file descriptor
* @file: pointer to file structure
* @band: band bitmap
*
* Return: negative on error,
* 0 if it did no changes,
* and positive a process was added or deleted
*/
static int mei_fasync(int fd, struct file *file, int band)
{
struct mei_cl *cl = file->private_data;
if (!mei_cl_is_connected(cl))
return -ENODEV;
return fasync_helper(fd, file, band, &cl->ev_async);
}
/**
* trc_show - mei device trc attribute show method
*
* @device: device pointer
* @attr: attribute pointer
* @buf: char out buffer
*
* Return: number of the bytes printed into buf or error
*/
static ssize_t trc_show(struct device *device,
struct device_attribute *attr, char *buf)
{
struct mei_device *dev = dev_get_drvdata(device);
u32 trc;
int ret;
ret = mei_trc_status(dev, &trc);
if (ret)
return ret;
return sprintf(buf, "%08X\n", trc);
}
static DEVICE_ATTR_RO(trc);
/**
* fw_status_show - mei device fw_status attribute show method
*
* @device: device pointer
* @attr: attribute pointer
* @buf: char out buffer
*
* Return: number of the bytes printed into buf or error
*/
static ssize_t fw_status_show(struct device *device,
struct device_attribute *attr, char *buf)
{
struct mei_device *dev = dev_get_drvdata(device);
struct mei_fw_status fw_status;
int err, i;
ssize_t cnt = 0;
mutex_lock(&dev->device_lock);
err = mei_fw_status(dev, &fw_status);
mutex_unlock(&dev->device_lock);
if (err) {
dev_err(device, "read fw_status error = %d\n", err);
return err;
}
for (i = 0; i < fw_status.count; i++)
cnt += scnprintf(buf + cnt, PAGE_SIZE - cnt, "%08X\n",
fw_status.status[i]);
return cnt;
}
static DEVICE_ATTR_RO(fw_status);
/**
* hbm_ver_show - display HBM protocol version negotiated with FW
*
* @device: device pointer
* @attr: attribute pointer
* @buf: char out buffer
*
* Return: number of the bytes printed into buf or error
*/
static ssize_t hbm_ver_show(struct device *device,
struct device_attribute *attr, char *buf)
{
struct mei_device *dev = dev_get_drvdata(device);
struct hbm_version ver;
mutex_lock(&dev->device_lock);
ver = dev->version;
mutex_unlock(&dev->device_lock);
return sprintf(buf, "%u.%u\n", ver.major_version, ver.minor_version);
}
static DEVICE_ATTR_RO(hbm_ver);
/**
* hbm_ver_drv_show - display HBM protocol version advertised by driver
*
* @device: device pointer
* @attr: attribute pointer
* @buf: char out buffer
*
* Return: number of the bytes printed into buf or error
*/
static ssize_t hbm_ver_drv_show(struct device *device,
struct device_attribute *attr, char *buf)
{
return sprintf(buf, "%u.%u\n", HBM_MAJOR_VERSION, HBM_MINOR_VERSION);
}
static DEVICE_ATTR_RO(hbm_ver_drv);
static ssize_t tx_queue_limit_show(struct device *device,
struct device_attribute *attr, char *buf)
{
struct mei_device *dev = dev_get_drvdata(device);
u8 size = 0;
mutex_lock(&dev->device_lock);
size = dev->tx_queue_limit;
mutex_unlock(&dev->device_lock);
return sysfs_emit(buf, "%u\n", size);
}
static ssize_t tx_queue_limit_store(struct device *device,
struct device_attribute *attr,
const char *buf, size_t count)
{
struct mei_device *dev = dev_get_drvdata(device);
u8 limit;
unsigned int inp;
int err;
err = kstrtouint(buf, 10, &inp);
if (err)
return err;
if (inp > MEI_TX_QUEUE_LIMIT_MAX || inp < MEI_TX_QUEUE_LIMIT_MIN)
return -EINVAL;
limit = inp;
mutex_lock(&dev->device_lock);
dev->tx_queue_limit = limit;
mutex_unlock(&dev->device_lock);
return count;
}
static DEVICE_ATTR_RW(tx_queue_limit);
/**
* fw_ver_show - display ME FW version
*
* @device: device pointer
* @attr: attribute pointer
* @buf: char out buffer
*
* Return: number of the bytes printed into buf or error
*/
static ssize_t fw_ver_show(struct device *device,
struct device_attribute *attr, char *buf)
{
struct mei_device *dev = dev_get_drvdata(device);
struct mei_fw_version *ver;
ssize_t cnt = 0;
int i;
ver = dev->fw_ver;
for (i = 0; i < MEI_MAX_FW_VER_BLOCKS; i++)
cnt += scnprintf(buf + cnt, PAGE_SIZE - cnt, "%u:%u.%u.%u.%u\n",
ver[i].platform, ver[i].major, ver[i].minor,
ver[i].hotfix, ver[i].buildno);
return cnt;
}
static DEVICE_ATTR_RO(fw_ver);
/**
* dev_state_show - display device state
*
* @device: device pointer
* @attr: attribute pointer
* @buf: char out buffer
*
* Return: number of the bytes printed into buf or error
*/
static ssize_t dev_state_show(struct device *device,
struct device_attribute *attr, char *buf)
{
struct mei_device *dev = dev_get_drvdata(device);
enum mei_dev_state dev_state;
mutex_lock(&dev->device_lock);
dev_state = dev->dev_state;
mutex_unlock(&dev->device_lock);
return sprintf(buf, "%s", mei_dev_state_str(dev_state));
}
static DEVICE_ATTR_RO(dev_state);
/**
* mei_set_devstate: set to new device state and notify sysfs file.
*
* @dev: mei_device
* @state: new device state
*/
void mei_set_devstate(struct mei_device *dev, enum mei_dev_state state)
{
struct device *clsdev;
if (dev->dev_state == state)
return;
dev->dev_state = state;
clsdev = class_find_device_by_devt(&mei_class, dev->cdev.dev);
if (clsdev) {
sysfs_notify(&clsdev->kobj, NULL, "dev_state");
put_device(clsdev);
}
}
/**
* kind_show - display device kind
*
* @device: device pointer
* @attr: attribute pointer
* @buf: char out buffer
*
* Return: number of the bytes printed into buf or error
*/
static ssize_t kind_show(struct device *device,
struct device_attribute *attr, char *buf)
{
struct mei_device *dev = dev_get_drvdata(device);
ssize_t ret;
if (dev->kind)
ret = sprintf(buf, "%s\n", dev->kind);
else
ret = sprintf(buf, "%s\n", "mei");
return ret;
}
static DEVICE_ATTR_RO(kind);
static struct attribute *mei_attrs[] = {
&dev_attr_fw_status.attr,
&dev_attr_hbm_ver.attr,
&dev_attr_hbm_ver_drv.attr,
&dev_attr_tx_queue_limit.attr,
&dev_attr_fw_ver.attr,
&dev_attr_dev_state.attr,
&dev_attr_trc.attr,
&dev_attr_kind.attr,
NULL
};
ATTRIBUTE_GROUPS(mei);
/*
* file operations structure will be used for mei char device.
*/
static const struct file_operations mei_fops = {
.owner = THIS_MODULE,
.read = mei_read,
.unlocked_ioctl = mei_ioctl,
.compat_ioctl = compat_ptr_ioctl,
.open = mei_open,
.release = mei_release,
.write = mei_write,
.poll = mei_poll,
.fsync = mei_fsync,
.fasync = mei_fasync,
};
/**
* mei_minor_get - obtain next free device minor number
*
* @dev: device pointer
*
* Return: allocated minor, or -ENOSPC if no free minor left
*/
static int mei_minor_get(struct mei_device *dev)
{
int ret;
mutex_lock(&mei_minor_lock);
ret = idr_alloc(&mei_idr, dev, 0, MEI_MAX_DEVS, GFP_KERNEL);
if (ret >= 0)
dev->minor = ret;
else if (ret == -ENOSPC)
dev_err(dev->dev, "too many mei devices\n");
mutex_unlock(&mei_minor_lock);
return ret;
}
/**
* mei_minor_free - mark device minor number as free
*
* @dev: device pointer
*/
static void mei_minor_free(struct mei_device *dev)
{
mutex_lock(&mei_minor_lock);
idr_remove(&mei_idr, dev->minor);
mutex_unlock(&mei_minor_lock);
}
int mei_register(struct mei_device *dev, struct device *parent)
{
struct device *clsdev; /* class device */
int ret, devno;
ret = mei_minor_get(dev);
if (ret < 0)
return ret;
/* Fill in the data structures */
devno = MKDEV(MAJOR(mei_devt), dev->minor);
cdev_init(&dev->cdev, &mei_fops);
dev->cdev.owner = parent->driver->owner;
/* Add the device */
ret = cdev_add(&dev->cdev, devno, 1);
if (ret) {
dev_err(parent, "unable to add device %d:%d\n",
MAJOR(mei_devt), dev->minor);
goto err_dev_add;
}
clsdev = device_create_with_groups(&mei_class, parent, devno,
dev, mei_groups,
"mei%d", dev->minor);
if (IS_ERR(clsdev)) {
dev_err(parent, "unable to create device %d:%d\n",
MAJOR(mei_devt), dev->minor);
ret = PTR_ERR(clsdev);
goto err_dev_create;
}
mei_dbgfs_register(dev, dev_name(clsdev));
return 0;
err_dev_create:
cdev_del(&dev->cdev);
err_dev_add:
mei_minor_free(dev);
return ret;
}
EXPORT_SYMBOL_GPL(mei_register);
void mei_deregister(struct mei_device *dev)
{
int devno;
devno = dev->cdev.dev;
cdev_del(&dev->cdev);
mei_dbgfs_deregister(dev);
device_destroy(&mei_class, devno);
mei_minor_free(dev);
}
EXPORT_SYMBOL_GPL(mei_deregister);
static int __init mei_init(void)
{
int ret;
ret = class_register(&mei_class);
if (ret)
return ret;
ret = alloc_chrdev_region(&mei_devt, 0, MEI_MAX_DEVS, "mei");
if (ret < 0) {
pr_err("unable to allocate char dev region\n");
goto err_class;
}
ret = mei_cl_bus_init();
if (ret < 0) {
pr_err("unable to initialize bus\n");
goto err_chrdev;
}
return 0;
err_chrdev:
unregister_chrdev_region(mei_devt, MEI_MAX_DEVS);
err_class:
class_unregister(&mei_class);
return ret;
}
static void __exit mei_exit(void)
{
unregister_chrdev_region(mei_devt, MEI_MAX_DEVS);
class_unregister(&mei_class);
mei_cl_bus_exit();
}
module_init(mei_init);
module_exit(mei_exit);
MODULE_AUTHOR("Intel Corporation");
MODULE_DESCRIPTION("Intel(R) Management Engine Interface");
MODULE_LICENSE("GPL v2");
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