shdma-of.c
1.91 KB
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
/*
* SHDMA Device Tree glue
*
* Copyright (C) 2013 Renesas Electronics Inc.
* Author: Guennadi Liakhovetski <g.liakhovetski@gmx.de>
*
* This is free software; you can redistribute it and/or modify
* it under the terms of version 2 of the GNU General Public License as
* published by the Free Software Foundation.
*/
#include <linux/dmaengine.h>
#include <linux/module.h>
#include <linux/of.h>
#include <linux/of_dma.h>
#include <linux/of_platform.h>
#include <linux/platform_device.h>
#include <linux/shdma-base.h>
#define to_shdma_chan(c) container_of(c, struct shdma_chan, dma_chan)
static struct dma_chan *shdma_of_xlate(struct of_phandle_args *dma_spec,
struct of_dma *ofdma)
{
u32 id = dma_spec->args[0];
dma_cap_mask_t mask;
struct dma_chan *chan;
if (dma_spec->args_count != 1)
return NULL;
dma_cap_zero(mask);
/* Only slave DMA channels can be allocated via DT */
dma_cap_set(DMA_SLAVE, mask);
chan = dma_request_channel(mask, shdma_chan_filter, (void *)id);
if (chan)
to_shdma_chan(chan)->hw_req = id;
return chan;
}
static int shdma_of_probe(struct platform_device *pdev)
{
const struct of_dev_auxdata *lookup = dev_get_platdata(&pdev->dev);
int ret;
ret = of_dma_controller_register(pdev->dev.of_node,
shdma_of_xlate, pdev);
if (ret < 0)
return ret;
ret = of_platform_populate(pdev->dev.of_node, NULL, lookup, &pdev->dev);
if (ret < 0)
of_dma_controller_free(pdev->dev.of_node);
return ret;
}
static const struct of_device_id shdma_of_match[] = {
{ .compatible = "renesas,shdma-mux", },
{ }
};
MODULE_DEVICE_TABLE(of, sh_dmae_of_match);
static struct platform_driver shdma_of = {
.driver = {
.owner = THIS_MODULE,
.name = "shdma-of",
.of_match_table = shdma_of_match,
},
.probe = shdma_of_probe,
};
module_platform_driver(shdma_of);
MODULE_LICENSE("GPL v2");
MODULE_DESCRIPTION("SH-DMA driver DT glue");
MODULE_AUTHOR("Guennadi Liakhovetski <g.liakhovetski@gmx.de>");