LXR linux/include/linux/platform

   1#ifndef __ASM_ARCH_DMA_H
   2#define __ASM_ARCH_DMA_H
   3
   4#include <linux/types.h>
   5#include <linux/dmaengine.h>
   6#include <linux/dma-mapping.h>
   7
   8/*
   9 * M2P channels.
  10 *
  11 * Note that these values are also directly used for setting the PPALLOC
  12 * register.
  13 */
  14#define EP93XX_DMA_I2S1         0
  15#define EP93XX_DMA_I2S2         1
  16#define EP93XX_DMA_AAC1         2
  17#define EP93XX_DMA_AAC2         3
  18#define EP93XX_DMA_AAC3         4
  19#define EP93XX_DMA_I2S3         5
  20#define EP93XX_DMA_UART1        6
  21#define EP93XX_DMA_UART2        7
  22#define EP93XX_DMA_UART3        8
  23#define EP93XX_DMA_IRDA         9
  24/* M2M channels */
  25#define EP93XX_DMA_SSP          10
  26#define EP93XX_DMA_IDE          11
  27
  28/**
  29 * struct ep93xx_dma_data - configuration data for the EP93xx dmaengine
  30 * @port: peripheral which is requesting the channel
  31 * @direction: TX/RX channel
  32 * @name: optional name for the channel, this is displayed in /proc/interrupts
  33 *
  34 * This information is passed as private channel parameter in a filter
  35 * function. Note that this is only needed for slave/cyclic channels.  For
  36 * memcpy channels %NULL data should be passed.
  37 */
  38struct ep93xx_dma_data {
  39        int                             port;
  40        enum dma_transfer_direction     direction;
  41        const char                      *name;
  42};
  43
  44/**
  45 * struct ep93xx_dma_chan_data - platform specific data for a DMA channel
  46 * @name: name of the channel, used for getting the right clock for the channel
  47 * @base: mapped registers
  48 * @irq: interrupt number used by this channel
  49 */
  50struct ep93xx_dma_chan_data {
  51        const char                      *name;
  52        void __iomem                    *base;
  53        int                             irq;
  54};
  55
  56/**
  57 * struct ep93xx_dma_platform_data - platform data for the dmaengine driver
  58 * @channels: array of channels which are passed to the driver
  59 * @num_channels: number of channels in the array
  60 *
  61 * This structure is passed to the DMA engine driver via platform data. For
  62 * M2P channels, contract is that even channels are for TX and odd for RX.
  63 * There is no requirement for the M2M channels.
  64 */
  65struct ep93xx_dma_platform_data {
  66        struct ep93xx_dma_chan_data     *channels;
  67        size_t                          num_channels;
  68};
  69
  70static inline bool ep93xx_dma_chan_is_m2p(struct dma_chan *chan)
  71{
  72        return !strcmp(dev_name(chan->device->dev), "ep93xx-dma-m2p");
  73}
  74
  75/**
  76 * ep93xx_dma_chan_direction - returns direction the channel can be used
  77 * @chan: channel
  78 *
  79 * This function can be used in filter functions to find out whether the
  80 * channel supports given DMA direction. Only M2P channels have such
  81 * limitation, for M2M channels the direction is configurable.
  82 */
  83static inline enum dma_transfer_direction
  84ep93xx_dma_chan_direction(struct dma_chan *chan)
  85{
  86        if (!ep93xx_dma_chan_is_m2p(chan))
  87                return DMA_NONE;
  88
  89        /* even channels are for TX, odd for RX */
  90        return (chan->chan_id % 2 == 0) ? DMA_MEM_TO_DEV : DMA_DEV_TO_MEM;
  91}
  92
  93#endif /* __ASM_ARCH_DMA_H */
  94