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);
49