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 */ 38 struct 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 */ 50 struct 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 */ 65 struct ep93xx_dma_platform_data { 66 struct ep93xx_dma_chan_data *channels; 67 size_t num_channels; 68 }; 69 70 static 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 */ 83 static inline enum dma_transfer_direction 84 ep93xx_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