Root/arch/arm/plat-samsung/dma.c

1/* linux/arch/arm/plat-samsung/dma.c
2 *
3 * Copyright (c) 2003-2009 Simtec Electronics
4 * Ben Dooks <ben@simtec.co.uk>
5 * http://armlinux.simtec.co.uk/
6 *
7 * S3C DMA core
8 *
9 * This program is free software; you can redistribute it and/or modify
10 * it under the terms of the GNU General Public License version 2 as
11 * published by the Free Software Foundation.
12*/
13
14struct s3c2410_dma_buf;
15
16#include <linux/kernel.h>
17#include <linux/module.h>
18#include <linux/errno.h>
19
20#include <mach/dma.h>
21#include <mach/irqs.h>
22
23/* dma channel state information */
24struct s3c2410_dma_chan s3c2410_chans[S3C_DMA_CHANNELS];
25struct s3c2410_dma_chan *s3c_dma_chan_map[DMACH_MAX];
26
27/* s3c_dma_lookup_channel
28 *
29 * change the dma channel number given into a real dma channel id
30*/
31
32struct s3c2410_dma_chan *s3c_dma_lookup_channel(unsigned int channel)
33{
34    if (channel & DMACH_LOW_LEVEL)
35        return &s3c2410_chans[channel & ~DMACH_LOW_LEVEL];
36    else
37        return s3c_dma_chan_map[channel];
38}
39
40/* do we need to protect the settings of the fields from
41 * irq?
42*/
43
44int s3c2410_dma_set_opfn(unsigned int channel, s3c2410_dma_opfn_t rtn)
45{
46    struct s3c2410_dma_chan *chan = s3c_dma_lookup_channel(channel);
47
48    if (chan == NULL)
49        return -EINVAL;
50
51    pr_debug("%s: chan=%p, op rtn=%p\n", __func__, chan, rtn);
52
53    chan->op_fn = rtn;
54
55    return 0;
56}
57EXPORT_SYMBOL(s3c2410_dma_set_opfn);
58
59int s3c2410_dma_set_buffdone_fn(unsigned int channel, s3c2410_dma_cbfn_t rtn)
60{
61    struct s3c2410_dma_chan *chan = s3c_dma_lookup_channel(channel);
62
63    if (chan == NULL)
64        return -EINVAL;
65
66    pr_debug("%s: chan=%p, callback rtn=%p\n", __func__, chan, rtn);
67
68    chan->callback_fn = rtn;
69
70    return 0;
71}
72EXPORT_SYMBOL(s3c2410_dma_set_buffdone_fn);
73
74int s3c2410_dma_setflags(unsigned int channel, unsigned int flags)
75{
76    struct s3c2410_dma_chan *chan = s3c_dma_lookup_channel(channel);
77
78    if (chan == NULL)
79        return -EINVAL;
80
81    chan->flags = flags;
82    return 0;
83}
84EXPORT_SYMBOL(s3c2410_dma_setflags);
85

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