tjh.dev
Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
kernel
os
linux
1/*
2 * S3C24XX DMA handling
3 *
4 * Copyright (c) 2013 Heiko Stuebner <heiko@sntech.de>
5 *
6 * This program is free software; you can redistribute it and/or modify it
7 * under the terms of the GNU General Public License as published by the Free
8 * Software Foundation; either version 2 of the License, or (at your option)
9 * any later version.
10 */
11
12/* Helper to encode the source selection constraints for early s3c socs. */
13#define S3C24XX_DMA_CHANREQ(src, chan) ((BIT(3) | src) << chan * 4)
14
15enum s3c24xx_dma_bus {
16 S3C24XX_DMA_APB,
17 S3C24XX_DMA_AHB,
18};
19
20/**
21 * @bus: on which bus does the peripheral reside - AHB or APB.
22 * @handshake: is a handshake with the peripheral necessary
23 * @chansel: channel selection information, depending on variant; reqsel for
24 * s3c2443 and later and channel-selection map for earlier SoCs
25 * see CHANSEL doc in s3c2443-dma.c
26 */
27struct s3c24xx_dma_channel {
28 enum s3c24xx_dma_bus bus;
29 bool handshake;
30 u16 chansel;
31};
32
33struct dma_slave_map;
34
35/**
36 * struct s3c24xx_dma_platdata - platform specific settings
37 * @num_phy_channels: number of physical channels
38 * @channels: array of virtual channel descriptions
39 * @num_channels: number of virtual channels
40 * @slave_map: dma slave map matching table
41 * @slavecnt: number of elements in slave_map
42 */
43struct s3c24xx_dma_platdata {
44 int num_phy_channels;
45 struct s3c24xx_dma_channel *channels;
46 int num_channels;
47 const struct dma_slave_map *slave_map;
48 int slavecnt;
49};
50
51struct dma_chan;
52bool s3c24xx_dma_filter(struct dma_chan *chan, void *param);