/*
*
* Intel Management Engine Interface (Intel MEI) Linux driver
* Copyright (c) 2003-2012, 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.
*
*/
#include <linux/kernel.h>
#include <linux/fs.h>
#include <linux/errno.h>
#include <linux/types.h>
#include <linux/fcntl.h>
#include <linux/ioctl.h>
#include <linux/cdev.h>
#include <linux/list.h>
#include <linux/delay.h>
#include <linux/sched.h>
#include <linux/uuid.h>
#include <linux/jiffies.h>
#include <linux/uaccess.h>
#include <linux/slab.h>
#include <linux/mei.h>
#include "mei_dev.h"
#include "hbm.h"
#include "client.h"
const uuid_le mei_amthif_guid = UUID_LE(0x12f80028, 0xb4b7, 0x4b2d,
0xac, 0xa8, 0x46, 0xe0,
0xff, 0x65, 0x81, 0x4c);
/**
* mei_amthif_reset_params - initializes mei device iamthif
*
* @dev: the device structure
*/
void mei_amthif_reset_params(struct mei_device *dev)
{
/* reset iamthif parameters. */
dev->iamthif_canceled = false;
dev->iamthif_state = MEI_IAMTHIF_IDLE;
dev->iamthif_stall_timer = 0;
dev->iamthif_open_count = 0;
}
/**
* mei_amthif_host_init - mei initialization amthif client.
*
* @dev: the device structure
* @me_cl: me client
*
* Return: 0 on success, <0 on failure.
*/
int mei_amthif_host_init(struct mei_device *dev, struct mei_me_client *me_cl)
{
struct mei_cl *cl = &dev->iamthif_cl;
int ret;
mutex_lock(&dev->device_lock);
if (mei_cl_is_connected(cl)) {
ret = 0;
goto out;
}
dev->iamthif_state = MEI_IAMTHIF_IDLE;
mei_cl_init(cl, dev);
ret = mei_cl_link(cl);
if (ret < 0) {
dev_err(dev->dev, "amthif: failed cl_link %d\n", ret);
goto out;
}
ret = mei_cl_connect(cl, me_cl, NULL);
out:
mutex_unlock(&dev->device_lock);
return ret;
}
/**
* mei_amthif_read_start - queue message for sending read credential
*
* @cl: host client
* @fp: file pointer of message recipient
*
* Return: 0 on success, <0 on failure.
*/
static int mei_amthif_read_start(struct mei_cl *cl, const struct file *fp)
{
struct mei_device *dev = cl->dev;
struct mei_cl_cb *cb;
cb = mei_cl_enqueue_ctrl_wr_cb(cl, mei_cl_mtu(cl), MEI_FOP_READ, fp);
if (!cb)
return -ENOMEM;
cl->rx_flow_ctrl_creds++;
dev->iamthif_state = MEI_IAMTHIF_READING;
cl->fp = cb->fp;
return 0;
}
/**
* mei_amthif_run_next_cmd - send next amt command from queue
*
* @dev: the device structure
*
* Return: 0 on success, <0 on failure.
*/
int mei_amthif_run_next_cmd(struct mei_device *dev)
{
struct mei_cl *cl = &dev->iamthif_cl;
struct mei_cl_cb *cb;
int ret;
dev->iamthif_canceled = false;
dev_dbg(dev->dev, "complete amthif cmd_list cb.\n");
cb = list_first_entry_or_null(&dev->amthif_cmd_list, typeof(*cb), list);
if (!cb) {
dev->iamthif_state = MEI_IAMTHIF_IDLE;
cl->fp = NULL;
return 0;
}
list_del_init(&cb->list);
dev->iamthif_state = MEI_IAMTHIF_WRITING;
cl->fp = cb->fp;
ret = mei_cl_write(cl, cb);
if (ret < 0)
return ret;
if (cb->completed)
cb->status = mei_amthif_read_start(cl, cb->fp);
return 0;
}
/**
* mei_amthif_write - write amthif data to amthif client
*
* @cl: host client
* @cb: mei call back struct
*
* Return: 0 on success, <0 on failure.
*/
int mei_amthif_write(struct mei_cl *cl, struct mei_cl_cb *cb)
{
struct mei_device *dev = cl->dev;
list_add_tail(&cb->list, &dev->amthif_cmd_list);
/*
* The previous request is still in processing, queue this one.
*/
if (dev->iamthif_state != MEI_IAMTHIF_IDLE)
return 0;
return mei_amthif_run_next_cmd(dev);
}
/**
* mei_amthif_poll - the amthif poll function
*
* @file: pointer to file structure
* @wait: pointer to poll_table structure
*
* Return: poll mask
*
* Locking: called under "dev->device_lock" lock
*/
unsigned int mei_amthif_poll(struct file *file, poll_table *wait)
{
struct mei_cl *cl = file->private_data;
struct mei_cl_cb *cb = mei_cl_read_cb(cl, file);
unsigned int mask = 0;
poll_wait(file, &cl->rx_wait, wait);
if (cb)
mask |= POLLIN | POLLRDNORM;
return mask;
}
/**
* mei_amthif_irq_write - write iamthif command in irq thread context.
*
* @cl: private data of the file object.
* @cb: callback block.
* @cmpl_list: complete list.
*
* Return: 0, OK; otherwise, error.
*/
int mei_amthif_irq_write(struct mei_cl *cl, struct mei_cl_cb *cb,
struct list_head *cmpl_list)
{
int ret;
ret = mei_cl_irq_write(cl, cb, cmpl_list);
if (ret)
return ret;
if (cb->completed)
cb->status = mei_amthif_read_start(cl, cb->fp);
return 0;
}
/**
* mei_amthif_irq_read_msg - read routine after ISR to
* handle the read amthif message
*
* @cl: mei client
* @mei_hdr: header of amthif message
* @cmpl_list: completed callbacks list
*
* Return: -ENODEV if cb is NULL 0 otherwise; error message is in cb->status
*/
int mei_amthif_irq_read_msg(struct mei_cl *cl,
struct mei_msg_hdr *mei_hdr,
struct list_head *cmpl_list)
{
struct mei_device *dev;
int ret;
dev = cl->dev;
if (dev->iamthif_state != MEI_IAMTHIF_READING) {
mei_irq_discard_msg(dev, mei_hdr);
return 0;
}
ret = mei_cl_irq_read_msg(cl, mei_hdr, cmpl_list);
if (ret)
return ret;
if (!mei_hdr->msg_complete)
return 0;
dev_dbg(dev->dev, "completed amthif read.\n ");
dev->iamthif_stall_timer = 0;
return 0;
}
/**
* mei_amthif_complete - complete amthif callback.
*
* @cl: host client
* @cb: callback block.
*/
void mei_amthif_complete(struct mei_cl *cl, struct mei_cl_cb *cb)
{
struct mei_device *dev = cl->dev;
dev_dbg(dev->dev, "completing amthif call back.\n");
switch (cb->fop_type) {
case MEI_FOP_WRITE:
if (!cb->status) {
dev->iamthif_stall_timer = MEI_IAMTHIF_STALL_TIMER;
mei_schedule_stall_timer(dev);
mei_io_cb_free(cb);
return;
}
dev->iamthif_state = MEI_IAMTHIF_IDLE;
cl->fp = NULL;
if (!dev->iamthif_canceled) {
/*
* in case of error enqueue the write cb to complete
* read list so it can be propagated to the reader
*/
list_add_tail(&cb->list, &cl->rd_completed);
wake_up_interruptible(&cl->rx_wait);
} else {
mei_io_cb_free(cb);
}
break;
case MEI_FOP_READ:
if (!dev->iamthif_canceled) {
list_add_tail(&cb->list, &cl->rd_completed);
dev_dbg(dev->dev, "amthif read completed\n");
wake_up_interruptible(&cl->rx_wait);
} else {
mei_io_cb_free(cb);
}
dev->iamthif_stall_timer = 0;
mei_amthif_run_next_cmd(dev);
break;
default:
WARN_ON(1);
}
}
/**
* mei_clear_list - removes all callbacks associated with file
* from mei_cb_list
*
* @file: file structure
* @mei_cb_list: callbacks list
*
* mei_clear_list is called to clear resources associated with file
* when application calls close function or Ctrl-C was pressed
*/
static void mei_clear_list(const struct file *file,
struct list_head *mei_cb_list)
{
struct mei_cl_cb *cb, *next;
list_for_each_entry_safe(cb, next, mei_cb_list, list)
if (file == cb->fp)
mei_io_cb_free(cb);
}
/**
* mei_amthif_release - the release function
*
* @dev: device structure
* @file: pointer to file structure
*
* Return: 0 on success, <0 on error
*/
int mei_amthif_release(struct mei_device *dev, struct file *file)
{
struct mei_cl *cl = file->private_data;
if (dev->iamthif_open_count > 0)
dev->iamthif_open_count--;
if (cl->fp == file && dev->iamthif_state != MEI_IAMTHIF_IDLE) {
dev_dbg(dev->dev, "amthif canceled iamthif state %d\n",
dev->iamthif_state);
dev->iamthif_canceled = true;
}
/* Don't clean ctrl_rd_list here, the reads has to be completed */
mei_clear_list(file, &dev->amthif_cmd_list);
mei_clear_list(file, &cl->rd_completed);
return 0;
}
