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/* SPDX-License-Identifier: GPL-2.0 */
#ifndef __ASM_ARCH_DMA_H
#define __ASM_ARCH_DMA_H
#include <linux/types.h>
#include <linux/dmaengine.h>
#include <linux/dma-mapping.h>
/*
* M2P channels.
*
* Note that these values are also directly used for setting the PPALLOC
* register.
*/
#define EP93XX_DMA_I2S1 0
#define EP93XX_DMA_I2S2 1
#define EP93XX_DMA_AAC1 2
#define EP93XX_DMA_AAC2 3
#define EP93XX_DMA_AAC3 4
#define EP93XX_DMA_I2S3 5
#define EP93XX_DMA_UART1 6
#define EP93XX_DMA_UART2 7
#define EP93XX_DMA_UART3 8
#define EP93XX_DMA_IRDA 9
/* M2M channels */
#define EP93XX_DMA_SSP 10
#define EP93XX_DMA_IDE 11
/**
* struct ep93xx_dma_data - configuration data for the EP93xx dmaengine
* @port: peripheral which is requesting the channel
* @direction: TX/RX channel
* @name: optional name for the channel, this is displayed in /proc/interrupts
*
* This information is passed as private channel parameter in a filter
* function. Note that this is only needed for slave/cyclic channels. For
* memcpy channels %NULL data should be passed.
*/
struct ep93xx_dma_data {
int port;
enum dma_transfer_direction direction;
const char *name;
};
/**
* struct ep93xx_dma_chan_data - platform specific data for a DMA channel
* @name: name of the channel, used for getting the right clock for the channel
* @base: mapped registers
* @irq: interrupt number used by this channel
*/
struct ep93xx_dma_chan_data {
const char *name;
void __iomem *base;
int irq;
};
/**
* struct ep93xx_dma_platform_data - platform data for the dmaengine driver
* @channels: array of channels which are passed to the driver
* @num_channels: number of channels in the array
*
* This structure is passed to the DMA engine driver via platform data. For
* M2P channels, contract is that even channels are for TX and odd for RX.
* There is no requirement for the M2M channels.
*/
struct ep93xx_dma_platform_data {
struct ep93xx_dma_chan_data *channels;
size_t num_channels;
};
static inline bool ep93xx_dma_chan_is_m2p(struct dma_chan *chan)
{
return !strcmp(dev_name(chan->device->dev), "ep93xx-dma-m2p");
}
/**
* ep93xx_dma_chan_direction - returns direction the channel can be used
* @chan: channel
*
* This function can be used in filter functions to find out whether the
* channel supports given DMA direction. Only M2P channels have such
* limitation, for M2M channels the direction is configurable.
*/
static inline enum dma_transfer_direction
ep93xx_dma_chan_direction(struct dma_chan *chan)
{
if (!ep93xx_dma_chan_is_m2p(chan))
return DMA_TRANS_NONE;
/* even channels are for TX, odd for RX */
return (chan->chan_id % 2 == 0) ? DMA_MEM_TO_DEV : DMA_DEV_TO_MEM;
}
#endif /* __ASM_ARCH_DMA_H */
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