include/asm-sh/dma.h

   1 /*
   2  * include/asm-sh/dma.h
   3  *
   4  * Copyright (C) 2003, 2004  Paul Mundt
   5  *
   6  * This file is subject to the terms and conditions of the GNU General Public
   7  * License.  See the file "COPYING" in the main directory of this archive
   8  * for more details.
   9  */
  10 #ifndef __ASM_SH_DMA_H
  11 #define __ASM_SH_DMA_H
  12 #ifdef __KERNEL__
  13
  14 #include <linux/config.h>
  15 #include <linux/spinlock.h>
  16 #include <linux/wait.h>
  17 #include <linux/sysdev.h>
  18 #include <asm/cpu/dma.h>
  19 #include <asm/semaphore.h>
  20
  21 /* The maximum address that we can perform a DMA transfer to on this platform */
  22 /* Don't define MAX_DMA_ADDRESS; it's useless on the SuperH and any
  23    occurrence should be flagged as an error.  */
  24 /* But... */
  25 /* XXX: This is not applicable to SuperH, just needed for alloc_bootmem */
  26 #define MAX_DMA_ADDRESS         (PAGE_OFFSET+0x10000000)
  27
  28 #ifdef CONFIG_NR_DMA_CHANNELS
  29 #  define MAX_DMA_CHANNELS      (CONFIG_NR_DMA_CHANNELS)
  30 #else
  31 #  define MAX_DMA_CHANNELS      (CONFIG_NR_ONCHIP_DMA_CHANNELS)
  32 #endif
  33
  34 /*
  35  * Read and write modes can mean drastically different things depending on the
  36  * channel configuration. Consult your DMAC documentation and module
  37  * implementation for further clues.
  38  */
  39 #define DMA_MODE_READ           0x00
  40 #define DMA_MODE_WRITE          0x01
  41 #define DMA_MODE_MASK           0x01
  42
  43 #define DMA_AUTOINIT            0x10
  44
  45 /*
  46  * DMAC (dma_info) flags
  47  */
  48 enum {
  49         DMAC_CHANNELS_CONFIGURED        = 0x00,
  50         DMAC_CHANNELS_TEI_CAPABLE       = 0x01,
  51 };
  52
  53 /*
  54  * DMA channel capabilities / flags
  55  */
  56 enum {
  57         DMA_CONFIGURED                  = 0x00,
  58         DMA_TEI_CAPABLE                 = 0x01,
  59 };
  60
  61 extern spinlock_t dma_spin_lock;
  62
  63 struct dma_channel;
  64
  65 struct dma_ops {
  66         int (*request)(struct dma_channel *chan);
  67         void (*free)(struct dma_channel *chan);
  68
  69         int (*get_residue)(struct dma_channel *chan);
  70         int (*xfer)(struct dma_channel *chan);
  71         void (*configure)(struct dma_channel *chan, unsigned long flags);
  72 };
  73
  74 struct dma_channel {
  75         char dev_id[16];
  76
  77         unsigned int chan;
  78         unsigned int mode;
  79         unsigned int count;
  80
  81         unsigned long sar;
  82         unsigned long dar;
  83
  84         unsigned long flags;
  85         atomic_t busy;
  86
  87         struct semaphore sem;
  88         wait_queue_head_t wait_queue;
  89
  90         struct sys_device dev;
  91 };
  92
  93 struct dma_info {
  94         const char *name;
  95         unsigned int nr_channels;
  96         unsigned long flags;
  97
  98         struct dma_ops *ops;
  99         struct dma_channel *channels;
 100
 101         struct list_head list;
 102 };
 103
 104 #define to_dma_channel(channel) container_of(channel, struct dma_channel, dev)
 105
 106 /* arch/sh/drivers/dma/dma-api.c */
 107 extern int dma_xfer(unsigned int chan, unsigned long from,
 108                     unsigned long to, size_t size, unsigned int mode);
 109
 110 #define dma_write(chan, from, to, size) \
 111         dma_xfer(chan, from, to, size, DMA_MODE_WRITE)
 112 #define dma_write_page(chan, from, to)  \
 113         dma_write(chan, from, to, PAGE_SIZE)
 114
 115 #define dma_read(chan, from, to, size)  \
 116         dma_xfer(chan, from, to, size, DMA_MODE_READ)
 117 #define dma_read_page(chan, from, to)   \
 118         dma_read(chan, from, to, PAGE_SIZE)
 119
 120 extern int request_dma(unsigned int chan, const char *dev_id);
 121 extern void free_dma(unsigned int chan);
 122 extern int get_dma_residue(unsigned int chan);
 123 extern struct dma_info *get_dma_info(unsigned int chan);
 124 extern struct dma_channel *get_dma_channel(unsigned int chan);
 125 extern void dma_wait_for_completion(unsigned int chan);
 126 extern void dma_configure_channel(unsigned int chan, unsigned long flags);
 127
 128 extern int register_dmac(struct dma_info *info);
 129 extern void unregister_dmac(struct dma_info *info);
 130
 131 #ifdef CONFIG_SYSFS
 132 /* arch/sh/drivers/dma/dma-sysfs.c */
 133 extern int dma_create_sysfs_files(struct dma_channel *);
 134 #endif
 135
 136 #ifdef CONFIG_PCI
 137 extern int isa_dma_bridge_buggy;
 138 #else
 139 #define isa_dma_bridge_buggy    (0)
 140 #endif
 141
 142 #endif /* __KERNEL__ */
 143 #endif /* __ASM_SH_DMA_H */