git.oblomov.eu Git - linux-2.6/blob - drivers/staging/line6/dumprequest.c

   1 /*
   2  * Line6 Linux USB driver - 0.8.0
   3  *
   4  * Copyright (C) 2004-2009 Markus Grabner (grabner@icg.tugraz.at)
   5  *
   6  *      This program is free software; you can redistribute it and/or
   7  *      modify it under the terms of the GNU General Public License as
   8  *      published by the Free Software Foundation, version 2.
   9  *
  10  */
  11
  12 #include "driver.h"
  13 #include "dumprequest.h"
  14
  15
  16 /*
  17         Set "dump in progress" flag.
  18 */
  19 void line6_dump_started(struct line6_dump_request *l6dr, int dest)
  20 {
  21         l6dr->in_progress = dest;
  22 }
  23
  24 /*
  25         Invalidate current channel, i.e., set "dump in progress" flag.
  26         Reading from the "dump" special file blocks until dump is completed.
  27 */
  28 void line6_invalidate_current(struct line6_dump_request *l6dr)
  29 {
  30         line6_dump_started(l6dr, LINE6_DUMP_CURRENT);
  31 }
  32
  33 /*
  34         Clear "dump in progress" flag and notify waiting processes.
  35 */
  36 void line6_dump_finished(struct line6_dump_request *l6dr)
  37 {
  38         l6dr->in_progress = LINE6_DUMP_NONE;
  39         wake_up_interruptible(&l6dr->wait);
  40 }
  41
  42 /*
  43         Send an asynchronous channel dump request.
  44 */
  45 int line6_dump_request_async(struct line6_dump_request *l6dr, struct usb_line6 *line6, int num)
  46 {
  47         int ret;
  48         line6_invalidate_current(l6dr);
  49         ret = line6_send_raw_message_async(line6, l6dr->reqbufs[num].buffer, l6dr->reqbufs[num].length);
  50
  51         if(ret < 0)
  52                 line6_dump_finished(l6dr);
  53
  54         return ret;
  55 }
  56
  57 /*
  58         Send an asynchronous dump request after a given interval.
  59 */
  60 void line6_startup_delayed(struct line6_dump_request *l6dr, int seconds,
  61                                                                                                          void (*function)(unsigned long), void *data)
  62 {
  63         l6dr->timer.expires = jiffies + seconds * HZ;
  64         l6dr->timer.function = function;
  65         l6dr->timer.data = (unsigned long)data;
  66         add_timer(&l6dr->timer);
  67 }
  68
  69 /*
  70         Wait for completion.
  71 */
  72 int line6_wait_dump(struct line6_dump_request *l6dr, int nonblock)
  73 {
  74         int retval = 0;
  75         DECLARE_WAITQUEUE(wait, current);
  76         add_wait_queue(&l6dr->wait, &wait);
  77         current->state = TASK_INTERRUPTIBLE;
  78
  79         while(l6dr->in_progress) {
  80                 if(nonblock) {
  81                         retval = -EAGAIN;
  82                         break;
  83                 }
  84
  85                 if(signal_pending(current)) {
  86                         retval = -ERESTARTSYS;
  87                         break;
  88                 }
  89                 else
  90                         schedule();
  91         }
  92
  93         current->state = TASK_RUNNING;
  94         remove_wait_queue(&l6dr->wait, &wait);
  95         return retval;
  96 }
  97
  98 /*
  99         Initialize dump request buffer.
 100 */
 101 int line6_dumpreq_initbuf(struct line6_dump_request *l6dr, const void *buf, size_t len, int num)
 102 {
 103         l6dr->reqbufs[num].buffer = kmalloc(len, GFP_KERNEL);
 104         if(l6dr->reqbufs[num].buffer == NULL) return -ENOMEM;
 105         memcpy(l6dr->reqbufs[num].buffer, buf, len);
 106         l6dr->reqbufs[num].length = len;
 107         return 0;
 108 }
 109
 110 /*
 111         Initialize dump request data structure (including one buffer).
 112 */
 113 int line6_dumpreq_init(struct line6_dump_request *l6dr, const void *buf, size_t len)
 114 {
 115         int ret;
 116         ret = line6_dumpreq_initbuf(l6dr, buf, len, 0);
 117         if(ret < 0) return ret;
 118         init_waitqueue_head(&l6dr->wait);
 119         init_timer(&l6dr->timer);
 120         return 0;
 121 }
 122
 123 /*
 124         Destruct dump request data structure.
 125 */
 126 void line6_dumpreq_destructbuf(struct line6_dump_request *l6dr, int num)
 127 {
 128         if(l6dr == NULL) return;
 129         if(l6dr->reqbufs[num].buffer == NULL) return;
 130         kfree(l6dr->reqbufs[num].buffer);
 131         l6dr->reqbufs[num].buffer = NULL;
 132 }
 133
 134 /*
 135         Destruct dump request data structure.
 136 */
 137 void line6_dumpreq_destruct(struct line6_dump_request *l6dr)
 138 {
 139         if(l6dr->reqbufs[0].buffer == NULL) return;
 140         line6_dumpreq_destructbuf(l6dr, 0);
 141         l6dr->ok = 1;
 142         del_timer_sync(&l6dr->timer);
 143 }