include/asm-arm/arch-s3c24a0/dma.h

   1 /*
   2  *  include/asm-arm/arch-s3c24a0/dma.h
   3  *
   4  *  $Id: dma.h,v 1.2 2005/11/28 03:55:11 gerg Exp $
   5  *
   6  * This program is free software; you can redistribute it and/or modify
   7  * it under the terms of the GNU General Public License version 2 as
   8  * published by the Free Software Foundation.
   9  *
  10  * Based on linux/include/asm-arm/arch-s3c2410/dma.h
  11  *
  12  */
  13
  14 #ifndef __ASM_ARCH_DMA_H__
  15 #define __ASM_ARCH_DMA_H__
  16
  17 #include "hardware.h"
  18
  19 #define MAX_DMA_ADDRESS 0xffffffff
  20
  21 /*
  22  * NB: By nandy
  23  * If MAX_DMA_CHANNELS is zero, It means that this architecuture not use
  24  * the regular generic DMA interface provided by kernel.
  25  * Why? I don't know. I will investigate S3C24A0 DMA model and generic
  26  * DMA interface. But not yet.
  27  */
  28 #define MAX_DMA_CHANNELS        0
  29
  30 /* The S3C24A0 has four internal DMA channels. */
  31 #define S3C24A0_DMA_CHANNELS    4
  32
  33 #define MAX_S3C24A0_DMA_CHANNELS        S3C24A0_DMA_CHANNELS
  34
  35 #define DMA_CH0                 0
  36 #define DMA_CH1                 1
  37 #define DMA_CH2                 2
  38 #define DMA_CH3                 3
  39
  40 #define DMA_BUF_WR              1
  41 #define DMA_BUF_RD              0
  42
  43 typedef void (*dma_callback_t)(void *buf_id, int size);
  44
  45 /* S3C24A0 DMA API */
  46 extern int elfin_request_dma(const char *device_id, dmach_t channel,
  47                                 dma_callback_t write_cb, dma_callback_t read_cb);
  48 extern int elfin_dma_queue_buffer(dmach_t channel, void *buf_id,
  49                                         dma_addr_t data, int size, int write);
  50 extern int elfin_dma_flush_all(dmach_t channel);
  51 extern void elfin_free_dma(dmach_t channel);
  52 extern int elfin_dma_get_current(dmach_t channel, void **buf_id, dma_addr_t *addr);
  53 extern int elfin_dma_stop(dmach_t channel);
  54
  55 #endif /* __ASM_ARCH_DMA_H__ */