tegrakernel/kernel/kernel-4.9/drivers/hid/intel-ish-hid/ishtp/init.c

116 lines
2.9 KiB
C

/*
* Initialization protocol for ISHTP driver
*
* Copyright (c) 2003-2016, 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/export.h>
#include <linux/slab.h>
#include <linux/sched.h>
#include <linux/miscdevice.h>
#include "ishtp-dev.h"
#include "hbm.h"
#include "client.h"
/**
* ishtp_dev_state_str() -Convert to string format
* @state: state to convert
*
* Convert state to string for prints
*
* Return: character pointer to converted string
*/
const char *ishtp_dev_state_str(int state)
{
switch (state) {
case ISHTP_DEV_INITIALIZING:
return "INITIALIZING";
case ISHTP_DEV_INIT_CLIENTS:
return "INIT_CLIENTS";
case ISHTP_DEV_ENABLED:
return "ENABLED";
case ISHTP_DEV_RESETTING:
return "RESETTING";
case ISHTP_DEV_DISABLED:
return "DISABLED";
case ISHTP_DEV_POWER_DOWN:
return "POWER_DOWN";
case ISHTP_DEV_POWER_UP:
return "POWER_UP";
default:
return "unknown";
}
}
/**
* ishtp_device_init() - ishtp device init
* @dev: ISHTP device instance
*
* After ISHTP device is alloacted, this function is used to initialize
* each field which includes spin lock, work struct and lists
*/
void ishtp_device_init(struct ishtp_device *dev)
{
dev->dev_state = ISHTP_DEV_INITIALIZING;
INIT_LIST_HEAD(&dev->cl_list);
INIT_LIST_HEAD(&dev->device_list);
dev->rd_msg_fifo_head = 0;
dev->rd_msg_fifo_tail = 0;
spin_lock_init(&dev->rd_msg_spinlock);
init_waitqueue_head(&dev->wait_hbm_recvd_msg);
spin_lock_init(&dev->read_list_spinlock);
spin_lock_init(&dev->device_lock);
spin_lock_init(&dev->device_list_lock);
spin_lock_init(&dev->cl_list_lock);
spin_lock_init(&dev->fw_clients_lock);
INIT_WORK(&dev->bh_hbm_work, bh_hbm_work_fn);
bitmap_zero(dev->host_clients_map, ISHTP_CLIENTS_MAX);
dev->open_handle_count = 0;
/*
* Reserving client ID 0 for ISHTP Bus Message communications
*/
bitmap_set(dev->host_clients_map, 0, 1);
INIT_LIST_HEAD(&dev->read_list.list);
}
EXPORT_SYMBOL(ishtp_device_init);
/**
* ishtp_start() - Start ISH processing
* @dev: ISHTP device instance
*
* Start ISHTP processing by sending query subscriber message
*
* Return: 0 on success else -ENODEV
*/
int ishtp_start(struct ishtp_device *dev)
{
if (ishtp_hbm_start_wait(dev)) {
dev_err(dev->devc, "HBM haven't started");
goto err;
}
/* suspend & resume notification - send QUERY_SUBSCRIBERS msg */
ishtp_query_subscribers(dev);
return 0;
err:
dev_err(dev->devc, "link layer initialization failed.\n");
dev->dev_state = ISHTP_DEV_DISABLED;
return -ENODEV;
}
EXPORT_SYMBOL(ishtp_start);