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hpios.c
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1 /******************************************************************************
2 
3  AudioScience HPI driver
4  Copyright (C) 1997-2012 AudioScience Inc. <[email protected]>
5 
6  This program is free software; you can redistribute it and/or modify
7  it under the terms of version 2 of the GNU General Public License as
8  published by the Free Software Foundation;
9 
10  This program is distributed in the hope that it will be useful,
11  but WITHOUT ANY WARRANTY; without even the implied warranty of
12  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
13  GNU General Public License for more details.
14 
15  You should have received a copy of the GNU General Public License
16  along with this program; if not, write to the Free Software
17  Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
18 
19 HPI Operating System function implementation for Linux
20 
21 (C) Copyright AudioScience Inc. 1997-2003
22 ******************************************************************************/
23 #define SOURCEFILE_NAME "hpios.c"
24 #include "hpi_internal.h"
25 #include "hpidebug.h"
26 #include <linux/delay.h>
27 #include <linux/sched.h>
28 
29 void hpios_delay_micro_seconds(u32 num_micro_sec)
30 {
31  if ((usecs_to_jiffies(num_micro_sec) > 1) && !in_interrupt()) {
32  /* MUST NOT SCHEDULE IN INTERRUPT CONTEXT! */
34  (num_micro_sec));
35  } else if (num_micro_sec <= 2000)
36  udelay(num_micro_sec);
37  else
38  mdelay(num_micro_sec / 1000);
39 
40 }
41 
47  struct pci_dev *pdev)
48 {
49  /*?? any benefit in using managed dmam_alloc_coherent? */
50  p_mem_area->vaddr =
51  dma_alloc_coherent(&pdev->dev, size, &p_mem_area->dma_handle,
53 
54  if (p_mem_area->vaddr) {
55  HPI_DEBUG_LOG(DEBUG, "allocated %d bytes, dma 0x%x vma %p\n",
56  size, (unsigned int)p_mem_area->dma_handle,
57  p_mem_area->vaddr);
58  p_mem_area->pdev = &pdev->dev;
59  p_mem_area->size = size;
60  return 0;
61  } else {
63  "failed to allocate %d bytes locked memory\n", size);
64  p_mem_area->size = 0;
65  return 1;
66  }
67 }
68 
70 {
71  if (p_mem_area->size) {
72  dma_free_coherent(p_mem_area->pdev, p_mem_area->size,
73  p_mem_area->vaddr, p_mem_area->dma_handle);
74  HPI_DEBUG_LOG(DEBUG, "freed %lu bytes, dma 0x%x vma %p\n",
75  (unsigned long)p_mem_area->size,
76  (unsigned int)p_mem_area->dma_handle,
77  p_mem_area->vaddr);
78  p_mem_area->size = 0;
79  return 0;
80  } else {
81  return 1;
82  }
83 }