drivers/staging/line6/dumprequest.c

   1 /*
   2  * Line6 Linux USB driver - 0.9.1beta
   3  *
   4  * Copyright (C) 2004-2010 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 <linux/slab.h>
  13
  14 #include "driver.h"
  15 #include "dumprequest.h"
  16
  17 /*
  18         Set "dump in progress" flag.
  19 */
  20 void line6_dump_started(struct line6_dump_request *l6dr, int dest)
  21 {
  22         l6dr->in_progress = dest;
  23 }
  24
  25 /*
  26         Invalidate current channel, i.e., set "dump in progress" flag.
  27         Reading from the "dump" special file blocks until dump is completed.
  28 */
  29 void line6_invalidate_current(struct line6_dump_request *l6dr)
  30 {
  31         line6_dump_started(l6dr, LINE6_DUMP_CURRENT);
  32 }
  33
  34 /*
  35         Clear "dump in progress" flag and notify waiting processes.
  36 */
  37 void line6_dump_finished(struct line6_dump_request *l6dr)
  38 {
  39         l6dr->in_progress = LINE6_DUMP_NONE;
  40         wake_up(&l6dr->wait);
  41 }
  42
  43 /*
  44         Send an asynchronous channel dump request.
  45 */
  46 int line6_dump_request_async(struct line6_dump_request *l6dr,
  47                              struct usb_line6 *line6, int num, int dest)
  48 {
  49         int ret;
  50         line6_dump_started(l6dr, dest);
  51         ret = line6_send_raw_message_async(line6, l6dr->reqbufs[num].buffer,
  52                                            l6dr->reqbufs[num].length);
  53
  54         if (ret < 0)
  55                 line6_dump_finished(l6dr);
  56
  57         return ret;
  58 }
  59
  60 /*
  61         Wait for completion (interruptible).
  62 */
  63 int line6_dump_wait_interruptible(struct line6_dump_request *l6dr)
  64 {
  65         return wait_event_interruptible(l6dr->wait,
  66                                         l6dr->in_progress == LINE6_DUMP_NONE);
  67 }
  68
  69 /*
  70         Wait for completion.
  71 */
  72 void line6_dump_wait(struct line6_dump_request *l6dr)
  73 {
  74         wait_event(l6dr->wait, l6dr->in_progress == LINE6_DUMP_NONE);
  75 }
  76
  77 /*
  78         Wait for completion (with timeout).
  79 */
  80 int line6_dump_wait_timeout(struct line6_dump_request *l6dr, long timeout)
  81 {
  82         return wait_event_timeout(l6dr->wait,
  83                                   l6dr->in_progress == LINE6_DUMP_NONE,
  84                                   timeout);
  85 }
  86
  87 /*
  88         Initialize dump request buffer.
  89 */
  90 int line6_dumpreq_initbuf(struct line6_dump_request *l6dr, const void *buf,
  91                           size_t len, int num)
  92 {
  93         l6dr->reqbufs[num].buffer = kmemdup(buf, len, GFP_KERNEL);
  94         if (l6dr->reqbufs[num].buffer == NULL)
  95                 return -ENOMEM;
  96         l6dr->reqbufs[num].length = len;
  97         return 0;
  98 }
  99
 100 /*
 101         Initialize dump request data structure (including one buffer).
 102 */
 103 int line6_dumpreq_init(struct line6_dump_request *l6dr, const void *buf,
 104                        size_t len)
 105 {
 106         int ret;
 107         ret = line6_dumpreq_initbuf(l6dr, buf, len, 0);
 108         if (ret < 0)
 109                 return ret;
 110         init_waitqueue_head(&l6dr->wait);
 111         return 0;
 112 }
 113
 114 /*
 115         Destruct dump request data structure.
 116 */
 117 void line6_dumpreq_destructbuf(struct line6_dump_request *l6dr, int num)
 118 {
 119         if (l6dr == NULL)
 120                 return;
 121         if (l6dr->reqbufs[num].buffer == NULL)
 122                 return;
 123         kfree(l6dr->reqbufs[num].buffer);
 124         l6dr->reqbufs[num].buffer = NULL;
 125 }
 126
 127 /*
 128         Destruct dump request data structure.
 129 */
 130 void line6_dumpreq_destruct(struct line6_dump_request *l6dr)
 131 {
 132         if (l6dr->reqbufs[0].buffer == NULL)
 133                 return;
 134         line6_dumpreq_destructbuf(l6dr, 0);
 135 }