1 /* linux/arch/arm/plat-samsung/dma-ops.c
3 * Copyright (c) 2011 Samsung Electronics Co., Ltd.
4 * http://www.samsung.com
6 * Samsung DMA Operations
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.
13 #include <linux/kernel.h>
14 #include <linux/errno.h>
15 #include <linux/amba/pl330.h>
16 #include <linux/scatterlist.h>
17 #include <linux/export.h>
21 static inline bool pl330_filter(struct dma_chan *chan, void *param)
23 struct dma_pl330_peri *peri = chan->private;
24 return peri->peri_id == (unsigned)param;
27 static unsigned samsung_dmadev_request(enum dma_ch dma_ch,
28 struct samsung_dma_info *info)
30 struct dma_chan *chan;
32 struct dma_slave_config slave_config;
35 dma_cap_set(info->cap, mask);
37 chan = dma_request_channel(mask, pl330_filter, (void *)dma_ch);
39 if (info->direction == DMA_FROM_DEVICE) {
40 memset(&slave_config, 0, sizeof(struct dma_slave_config));
41 slave_config.direction = info->direction;
42 slave_config.src_addr = info->fifo;
43 slave_config.src_addr_width = info->width;
44 slave_config.src_maxburst = 1;
45 dmaengine_slave_config(chan, &slave_config);
46 } else if (info->direction == DMA_TO_DEVICE) {
47 memset(&slave_config, 0, sizeof(struct dma_slave_config));
48 slave_config.direction = info->direction;
49 slave_config.dst_addr = info->fifo;
50 slave_config.dst_addr_width = info->width;
51 slave_config.dst_maxburst = 1;
52 dmaengine_slave_config(chan, &slave_config);
55 return (unsigned)chan;
58 static int samsung_dmadev_release(unsigned ch,
59 struct s3c2410_dma_client *client)
61 dma_release_channel((struct dma_chan *)ch);
66 static int samsung_dmadev_prepare(unsigned ch,
67 struct samsung_dma_prep_info *info)
69 struct scatterlist sg;
70 struct dma_chan *chan = (struct dma_chan *)ch;
71 struct dma_async_tx_descriptor *desc;
75 sg_init_table(&sg, 1);
76 sg_dma_len(&sg) = info->len;
77 sg_set_page(&sg, pfn_to_page(PFN_DOWN(info->buf)),
78 info->len, offset_in_page(info->buf));
79 sg_dma_address(&sg) = info->buf;
81 desc = chan->device->device_prep_slave_sg(chan,
82 &sg, 1, info->direction, DMA_PREP_INTERRUPT);
85 desc = chan->device->device_prep_dma_cyclic(chan,
86 info->buf, info->len, info->period, info->direction);
89 dev_err(&chan->dev->device, "unsupported format\n");
94 dev_err(&chan->dev->device, "cannot prepare cyclic dma\n");
98 desc->callback = info->fp;
99 desc->callback_param = info->fp_param;
101 dmaengine_submit((struct dma_async_tx_descriptor *)desc);
106 static inline int samsung_dmadev_trigger(unsigned ch)
108 dma_async_issue_pending((struct dma_chan *)ch);
113 static inline int samsung_dmadev_flush(unsigned ch)
115 return dmaengine_terminate_all((struct dma_chan *)ch);
118 struct samsung_dma_ops dmadev_ops = {
119 .request = samsung_dmadev_request,
120 .release = samsung_dmadev_release,
121 .prepare = samsung_dmadev_prepare,
122 .trigger = samsung_dmadev_trigger,
124 .flush = samsung_dmadev_flush,
125 .stop = samsung_dmadev_flush,
128 void *samsung_dmadev_get_ops(void)
132 EXPORT_SYMBOL(samsung_dmadev_get_ops);