1 /* SPDX-License-Identifier: GPL-2.0-or-later */
2 /*
3 * S3C24XX DMA handling
4 *
5 * Copyright (c) 2013 Heiko Stuebner <heiko@sntech.de>
6 */
7
8 /* Helper to encode the source selection constraints for early s3c socs. */
9 #define S3C24XX_DMA_CHANREQ(src, chan) ((BIT(3) | src) << chan * 4)
10
11 enum s3c24xx_dma_bus {
12 S3C24XX_DMA_APB,
13 S3C24XX_DMA_AHB,
14 };
15
16 /**
17 * @bus: on which bus does the peripheral reside - AHB or APB.
18 * @handshake: is a handshake with the peripheral necessary
19 * @chansel: channel selection information, depending on variant; reqsel for
20 * s3c2443 and later and channel-selection map for earlier SoCs
21 * see CHANSEL doc in s3c2443-dma.c
22 */
23 struct s3c24xx_dma_channel {
24 enum s3c24xx_dma_bus bus;
25 bool handshake;
26 u16 chansel;
27 };
28
29 struct dma_slave_map;
30
31 /**
32 * struct s3c24xx_dma_platdata - platform specific settings
33 * @num_phy_channels: number of physical channels
34 * @channels: array of virtual channel descriptions
35 * @num_channels: number of virtual channels
36 * @slave_map: dma slave map matching table
37 * @slavecnt: number of elements in slave_map
38 */
39 struct s3c24xx_dma_platdata {
40 int num_phy_channels;
41 struct s3c24xx_dma_channel *channels;
42 int num_channels;
43 const struct dma_slave_map *slave_map;
44 int slavecnt;
45 };
46
47 struct dma_chan;
48 bool s3c24xx_dma_filter(struct dma_chan *chan, void *param);