xref: /linux/arch/sh/include/asm/dma.h (revision 8ea636848aca35b9f97c5b5dee30225cf2dd0fe6)
1 /* SPDX-License-Identifier: GPL-2.0
2  *
3  * include/asm-sh/dma.h
4  *
5  * Copyright (C) 2003, 2004  Paul Mundt
6  */
7 #ifndef __ASM_SH_DMA_H
8 #define __ASM_SH_DMA_H
9 
10 #include <linux/spinlock.h>
11 #include <linux/wait.h>
12 #include <linux/sched.h>
13 #include <linux/device.h>
14 #include <asm-generic/dma.h>
15 
16 /*
17  * Read and write modes can mean drastically different things depending on the
18  * channel configuration. Consult your DMAC documentation and module
19  * implementation for further clues.
20  */
21 #define DMA_MODE_READ		0x00
22 #define DMA_MODE_WRITE		0x01
23 #define DMA_MODE_MASK		0x01
24 
25 #define DMA_AUTOINIT		0x10
26 
27 /*
28  * DMAC (dma_info) flags
29  */
30 enum {
31 	DMAC_CHANNELS_CONFIGURED	= 0x01,
32 	DMAC_CHANNELS_TEI_CAPABLE	= 0x02,	/* Transfer end interrupt */
33 };
34 
35 /*
36  * DMA channel capabilities / flags
37  */
38 enum {
39 	DMA_CONFIGURED			= 0x01,
40 
41 	/*
42 	 * Transfer end interrupt, inherited from DMAC.
43 	 * wait_queue used in dma_wait_for_completion.
44 	 */
45 	DMA_TEI_CAPABLE			= 0x02,
46 };
47 
48 extern spinlock_t dma_spin_lock;
49 
50 struct dma_channel;
51 
52 struct dma_ops {
53 	int (*request)(struct dma_channel *chan);
54 	void (*free)(struct dma_channel *chan);
55 
56 	int (*get_residue)(struct dma_channel *chan);
57 	int (*xfer)(struct dma_channel *chan);
58 	int (*configure)(struct dma_channel *chan, unsigned long flags);
59 	int (*extend)(struct dma_channel *chan, unsigned long op, void *param);
60 };
61 
62 struct dma_channel {
63 	char dev_id[16];		/* unique name per DMAC of channel */
64 
65 	unsigned int chan;		/* DMAC channel number */
66 	unsigned int vchan;		/* Virtual channel number */
67 
68 	unsigned int mode;
69 	unsigned int count;
70 
71 	unsigned long sar;
72 	unsigned long dar;
73 
74 	const char **caps;
75 
76 	unsigned long flags;
77 	atomic_t busy;
78 
79 	wait_queue_head_t wait_queue;
80 
81 	struct device dev;
82 	void *priv_data;
83 };
84 
85 struct dma_info {
86 	struct platform_device *pdev;
87 
88 	const char *name;
89 	unsigned int nr_channels;
90 	unsigned long flags;
91 
92 	struct dma_ops *ops;
93 	struct dma_channel *channels;
94 
95 	struct list_head list;
96 	int first_channel_nr;
97 	int first_vchannel_nr;
98 };
99 
100 struct dma_chan_caps {
101 	int ch_num;
102 	const char **caplist;
103 };
104 
105 #define to_dma_channel(channel) container_of(channel, struct dma_channel, dev)
106 
107 /* arch/sh/drivers/dma/dma-api.c */
108 extern int dma_xfer(unsigned int chan, unsigned long from,
109 		    unsigned long to, size_t size, unsigned int mode);
110 
111 #define dma_write(chan, from, to, size)	\
112 	dma_xfer(chan, from, to, size, DMA_MODE_WRITE)
113 #define dma_write_page(chan, from, to)	\
114 	dma_write(chan, from, to, PAGE_SIZE)
115 
116 #define dma_read(chan, from, to, size)	\
117 	dma_xfer(chan, from, to, size, DMA_MODE_READ)
118 #define dma_read_page(chan, from, to)	\
119 	dma_read(chan, from, to, PAGE_SIZE)
120 
121 extern int request_dma_bycap(const char **dmac, const char **caps,
122 			     const char *dev_id);
123 extern int get_dma_residue(unsigned int chan);
124 extern struct dma_info *get_dma_info(unsigned int chan);
125 extern struct dma_channel *get_dma_channel(unsigned int chan);
126 extern void dma_wait_for_completion(unsigned int chan);
127 extern void dma_configure_channel(unsigned int chan, unsigned long flags);
128 
129 extern int register_dmac(struct dma_info *info);
130 extern void unregister_dmac(struct dma_info *info);
131 extern struct dma_info *get_dma_info_by_name(const char *dmac_name);
132 
133 extern int dma_extend(unsigned int chan, unsigned long op, void *param);
134 extern int register_chan_caps(const char *dmac, struct dma_chan_caps *capslist);
135 
136 /* arch/sh/drivers/dma/dma-sysfs.c */
137 extern int dma_create_sysfs_files(struct dma_channel *, struct dma_info *);
138 extern void dma_remove_sysfs_files(struct dma_channel *, struct dma_info *);
139 
140 #ifdef CONFIG_PCI
141 extern int isa_dma_bridge_buggy;
142 #else
143 #define isa_dma_bridge_buggy	(0)
144 #endif
145 
146 #endif /* __ASM_SH_DMA_H */
147