1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
|
/*
* arch/arm/kernel/dma.h
*
* Copyright (C) 1998 Russell King
*
* This header file describes the interface between the generic DMA handler
* (dma.c) and the architecture-specific DMA backends (dma-*.c)
*/
typedef struct {
dmasg_t buf; /* single DMA */
int sgcount; /* number of DMA SG */
dmasg_t *sg; /* DMA Scatter-Gather List */
unsigned int active:1; /* Transfer active */
unsigned int invalid:1; /* Address/Count changed */
dmamode_t dma_mode; /* DMA mode */
unsigned int lock; /* Device is allocated */
const char *device_id; /* Device name */
unsigned int dma_base; /* Controller base address */
int dma_irq; /* Controller IRQ */
int state; /* Controller state */
dmasg_t cur_sg; /* Current controller buffer */
} dma_t;
/* Prototype: int arch_request_dma(channel, dma, dev_id)
* Purpose : Perform architecture specific claiming of a DMA channel
* Params : channel - DMA channel number
* : dma - DMA structure (above) for channel
* : dev_id - device ID string passed with request
* Returns : 0 on success, E????? number on error
*/
int arch_request_dma(dmach_t channel, dma_t *dma, const char *dev_id);
/* Prototype: int arch_free_dma(channel, dma)
* Purpose : Perform architecture specific freeing of a DMA channel
* Params : channel - DMA channel number
* : dma - DMA structure for channel
*/
void arch_free_dma(dmach_t channel, dma_t *dma);
/* Prototype: void arch_enable_dma(channel, dma)
* Purpose : Enable a claimed DMA channel
* Params : channel - DMA channel number
* : dma - DMA structure for channel
*/
void arch_enable_dma(dmach_t channel, dma_t *dma);
/* Prototype: void arch_disable_dma(channel, dma)
* Purpose : Disable a claimed DMA channel
* Params : channel - DMA channel number
* : dma - DMA structure for channel
*/
void arch_disable_dma(dmach_t channel, dma_t *dma);
/* Prototype: int arch_get_dma_residue(channel, dma)
* Purpose : Return number of bytes left to DMA
* Params : channel - DMA channel number
* : dma - DMA structure for channel
* Returns : Number of bytes left to DMA
*/
int arch_get_dma_residue(dmach_t channel, dma_t *dma);
/* Prototype: void arch_dma_init(dma)
* Purpose : Initialise architecture specific DMA
* Params : dma - pointer to array of DMA structures
*/
void arch_dma_init(dma_t *dma);
|
