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 "ishtp-dev.h"
  20 #include "hbm.h"
  21 #include "client.h"
  22
  23 /**
  24  * ishtp_dev_state_str() -Convert to string format
  25  * @state: state to convert
  26  *
  27  * Convert state to string for prints
  28  *
  29  * Return: character pointer to converted string
  30  */
  31 const char *ishtp_dev_state_str(int state)
  32 {
  33         switch (state) {
  34         case ISHTP_DEV_INITIALIZING:
  35                 return  "INITIALIZING";
  36         case ISHTP_DEV_INIT_CLIENTS:
  37                 return  "INIT_CLIENTS";
  38         case ISHTP_DEV_ENABLED:
  39                 return  "ENABLED";
  40         case ISHTP_DEV_RESETTING:
  41                 return  "RESETTING";
  42         case ISHTP_DEV_DISABLED:
  43                 return  "DISABLED";
  44         case ISHTP_DEV_POWER_DOWN:
  45                 return  "POWER_DOWN";
  46         case ISHTP_DEV_POWER_UP:
  47                 return  "POWER_UP";
  48         default:
  49                 return "unknown";
  50         }
  51 }
  52
  53 /**
  54  * ishtp_device_init() - ishtp device init
  55  * @dev: ISHTP device instance
  56  *
  57  * After ISHTP device is alloacted, this function is used to initialize
  58  * each field which includes spin lock, work struct and lists
  59  */
  60 void ishtp_device_init(struct ishtp_device *dev)
  61 {
  62         dev->dev_state = ISHTP_DEV_INITIALIZING;
  63         INIT_LIST_HEAD(&dev->cl_list);
  64         INIT_LIST_HEAD(&dev->device_list);
  65         dev->rd_msg_fifo_head = 0;
  66         dev->rd_msg_fifo_tail = 0;
  67         spin_lock_init(&dev->rd_msg_spinlock);
  68
  69         init_waitqueue_head(&dev->wait_hbm_recvd_msg);
  70         spin_lock_init(&dev->read_list_spinlock);
  71         spin_lock_init(&dev->device_lock);
  72         spin_lock_init(&dev->device_list_lock);
  73         spin_lock_init(&dev->cl_list_lock);
  74         spin_lock_init(&dev->fw_clients_lock);
  75         INIT_WORK(&dev->bh_hbm_work, bh_hbm_work_fn);
  76
  77         bitmap_zero(dev->host_clients_map, ISHTP_CLIENTS_MAX);
  78         dev->open_handle_count = 0;
  79
  80         /*
  81          * Reserving client ID 0 for ISHTP Bus Message communications
  82          */
  83         bitmap_set(dev->host_clients_map, 0, 1);
  84
  85         INIT_LIST_HEAD(&dev->read_list.list);
  86
  87 }
  88 EXPORT_SYMBOL(ishtp_device_init);
  89
  90 /**
  91  * ishtp_start() - Start ISH processing
  92  * @dev: ISHTP device instance
  93  *
  94  * Start ISHTP processing by sending query subscriber message
  95  *
  96  * Return: 0 on success else -ENODEV
  97  */
  98 int ishtp_start(struct ishtp_device *dev)
  99 {
 100         if (ishtp_hbm_start_wait(dev)) {
 101                 dev_err(dev->devc, "HBM haven't started");
 102                 goto err;
 103         }
 104
 105         /* suspend & resume notification - send QUERY_SUBSCRIBERS msg */
 106         ishtp_query_subscribers(dev);
 107
 108         return 0;
 109 err:
 110         dev_err(dev->devc, "link layer initialization failed.\n");
 111         dev->dev_state = ISHTP_DEV_DISABLED;
 112         return -ENODEV;
 113 }
 114 EXPORT_SYMBOL(ishtp_start);