1 /* linux/arch/arm/plat-samsung/s3c-dma-ops.c
2 *
3 * Copyright (c) 2011 Samsung Electronics Co., Ltd.
4 * http://www.samsung.com
5 *
6 * Samsung S3C-DMA Operations
7 *
8 * This program is free software; you can redistribute it and/or modify
9 * it under the terms of the GNU General Public License version 2 as
10 * published by the Free Software Foundation.
11 */
12
13 #include <linux/kernel.h>
14 #include <linux/errno.h>
15 #include <linux/slab.h>
16 #include <linux/types.h>
17 #include <linux/export.h>
18
19 #include <mach/dma.h>
20
21 struct cb_data {
22 void (*fp) (void *);
23 void *fp_param;
24 unsigned ch;
25 struct list_head node;
26 };
27
28 static LIST_HEAD(dma_list);
29
s3c_dma_cb(struct s3c2410_dma_chan * channel,void * param,int size,enum s3c2410_dma_buffresult res)30 static void s3c_dma_cb(struct s3c2410_dma_chan *channel, void *param,
31 int size, enum s3c2410_dma_buffresult res)
32 {
33 struct cb_data *data = param;
34
35 data->fp(data->fp_param);
36 }
37
s3c_dma_request(enum dma_ch dma_ch,struct samsung_dma_info * info)38 static unsigned s3c_dma_request(enum dma_ch dma_ch,
39 struct samsung_dma_info *info)
40 {
41 struct cb_data *data;
42
43 if (s3c2410_dma_request(dma_ch, info->client, NULL) < 0) {
44 s3c2410_dma_free(dma_ch, info->client);
45 return 0;
46 }
47
48 data = kzalloc(sizeof(struct cb_data), GFP_KERNEL);
49 data->ch = dma_ch;
50 list_add_tail(&data->node, &dma_list);
51
52 s3c2410_dma_devconfig(dma_ch, info->direction, info->fifo);
53
54 if (info->cap == DMA_CYCLIC)
55 s3c2410_dma_setflags(dma_ch, S3C2410_DMAF_CIRCULAR);
56
57 s3c2410_dma_config(dma_ch, info->width);
58
59 return (unsigned)dma_ch;
60 }
61
s3c_dma_release(unsigned ch,struct s3c2410_dma_client * client)62 static int s3c_dma_release(unsigned ch, struct s3c2410_dma_client *client)
63 {
64 struct cb_data *data;
65
66 list_for_each_entry(data, &dma_list, node)
67 if (data->ch == ch)
68 break;
69 list_del(&data->node);
70
71 s3c2410_dma_free(ch, client);
72 kfree(data);
73
74 return 0;
75 }
76
s3c_dma_prepare(unsigned ch,struct samsung_dma_prep_info * info)77 static int s3c_dma_prepare(unsigned ch, struct samsung_dma_prep_info *info)
78 {
79 struct cb_data *data;
80 int len = (info->cap == DMA_CYCLIC) ? info->period : info->len;
81
82 list_for_each_entry(data, &dma_list, node)
83 if (data->ch == ch)
84 break;
85
86 if (!data->fp) {
87 s3c2410_dma_set_buffdone_fn(ch, s3c_dma_cb);
88 data->fp = info->fp;
89 data->fp_param = info->fp_param;
90 }
91
92 s3c2410_dma_enqueue(ch, (void *)data, info->buf, len);
93
94 return 0;
95 }
96
s3c_dma_trigger(unsigned ch)97 static inline int s3c_dma_trigger(unsigned ch)
98 {
99 return s3c2410_dma_ctrl(ch, S3C2410_DMAOP_START);
100 }
101
s3c_dma_started(unsigned ch)102 static inline int s3c_dma_started(unsigned ch)
103 {
104 return s3c2410_dma_ctrl(ch, S3C2410_DMAOP_STARTED);
105 }
106
s3c_dma_flush(unsigned ch)107 static inline int s3c_dma_flush(unsigned ch)
108 {
109 return s3c2410_dma_ctrl(ch, S3C2410_DMAOP_FLUSH);
110 }
111
s3c_dma_stop(unsigned ch)112 static inline int s3c_dma_stop(unsigned ch)
113 {
114 return s3c2410_dma_ctrl(ch, S3C2410_DMAOP_STOP);
115 }
116
117 static struct samsung_dma_ops s3c_dma_ops = {
118 .request = s3c_dma_request,
119 .release = s3c_dma_release,
120 .prepare = s3c_dma_prepare,
121 .trigger = s3c_dma_trigger,
122 .started = s3c_dma_started,
123 .flush = s3c_dma_flush,
124 .stop = s3c_dma_stop,
125 };
126
s3c_dma_get_ops(void)127 void *s3c_dma_get_ops(void)
128 {
129 return &s3c_dma_ops;
130 }
131 EXPORT_SYMBOL(s3c_dma_get_ops);
132