drivers/hid/intel-ish-hid/ishtp/init.c

   1 /*
   2  * Initialization protocol for ISHTP driver
   3  *
   4  * Copyright (c) 2003-2016, Intel Corporation.
   5  *
   6  * This program is free software; you can redistribute it and/or modify it
   7  * under the terms and conditions of the GNU General Public License,
   8  * version 2, as published by the Free Software Foundation.
   9  *
  10  * This program is distributed in the hope it will be useful, but WITHOUT
  11  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  12  * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
  13  * more details.
  14  */
  15
  16 #include <linux/export.h>
  17 #include <linux/slab.h>
  18 #include <linux/sched.h>
  19 #include <linux/miscdevice.h>
  20 #include "ishtp-dev.h"
  21 #include "hbm.h"
  22 #include "client.h"
  23
  24 /**
  25  * ishtp_dev_state_str() -Convert to string format
  26  * @state: state to convert
  27  *
  28  * Convert state to string for prints
  29  *
  30  * Return: character pointer to converted string
  31  */
  32 const char *ishtp_dev_state_str(int state)
  33 {
  34         switch (state) {
  35         case ISHTP_DEV_INITIALIZING:
  36                 return  "INITIALIZING";
  37         case ISHTP_DEV_INIT_CLIENTS:
  38                 return  "INIT_CLIENTS";
  39         case ISHTP_DEV_ENABLED:
  40                 return  "ENABLED";
  41         case ISHTP_DEV_RESETTING:
  42                 return  "RESETTING";
  43         case ISHTP_DEV_DISABLED:
  44                 return  "DISABLED";
  45         case ISHTP_DEV_POWER_DOWN:
  46                 return  "POWER_DOWN";
  47         case ISHTP_DEV_POWER_UP:
  48                 return  "POWER_UP";
  49         default:
  50                 return "unknown";
  51         }
  52 }
  53
  54 /**
  55  * ishtp_device_init() - ishtp device init
  56  * @dev: ISHTP device instance
  57  *
  58  * After ISHTP device is alloacted, this function is used to initialize
  59  * each field which includes spin lock, work struct and lists
  60  */
  61 void ishtp_device_init(struct ishtp_device *dev)
  62 {
  63         dev->dev_state = ISHTP_DEV_INITIALIZING;
  64         INIT_LIST_HEAD(&dev->cl_list);
  65         INIT_LIST_HEAD(&dev->device_list);
  66         dev->rd_msg_fifo_head = 0;
  67         dev->rd_msg_fifo_tail = 0;
  68         spin_lock_init(&dev->rd_msg_spinlock);
  69
  70         init_waitqueue_head(&dev->wait_hbm_recvd_msg);
  71         spin_lock_init(&dev->read_list_spinlock);
  72         spin_lock_init(&dev->device_lock);
  73         spin_lock_init(&dev->device_list_lock);
  74         spin_lock_init(&dev->cl_list_lock);
  75         spin_lock_init(&dev->fw_clients_lock);
  76         INIT_WORK(&dev->bh_hbm_work, bh_hbm_work_fn);
  77
  78         bitmap_zero(dev->host_clients_map, ISHTP_CLIENTS_MAX);
  79         dev->open_handle_count = 0;
  80
  81         /*
  82          * Reserving client ID 0 for ISHTP Bus Message communications
  83          */
  84         bitmap_set(dev->host_clients_map, 0, 1);
  85
  86         INIT_LIST_HEAD(&dev->read_list.list);
  87
  88 }
  89 EXPORT_SYMBOL(ishtp_device_init);
  90
  91 /**
  92  * ishtp_start() - Start ISH processing
  93  * @dev: ISHTP device instance
  94  *
  95  * Start ISHTP processing by sending query subscriber message
  96  *
  97  * Return: 0 on success else -ENODEV
  98  */
  99 int ishtp_start(struct ishtp_device *dev)
 100 {
 101         if (ishtp_hbm_start_wait(dev)) {
 102                 dev_err(dev->devc, "HBM haven't started");
 103                 goto err;
 104         }
 105
 106         /* suspend & resume notification - send QUERY_SUBSCRIBERS msg */
 107         ishtp_query_subscribers(dev);
 108
 109         return 0;
 110 err:
 111         dev_err(dev->devc, "link layer initialization failed.\n");
 112         dev->dev_state = ISHTP_DEV_DISABLED;
 113         return -ENODEV;
 114 }
 115 EXPORT_SYMBOL(ishtp_start);