include/linux/dma/mxs-dma.h

Source file repositories/reference/linux-study-clean/include/linux/dma/mxs-dma.h

File Facts

System
Linux kernel
Corpus path
include/linux/dma/mxs-dma.h
Extension
.h
Size
798 bytes
Lines
25
Domain
Core OS
Bucket
Core Kernel Interface
Inferred role
Core OS: implementation source
Status
source implementation candidate

Why This File Exists

Core operating-system implementation surface: boot, tasks, memory, VFS, syscall-facing interfaces, synchronization, credentials, and isolation.

Dependency Surface

Detected Declarations

Annotated Snippet

#ifndef _MXS_DMA_H_
#define _MXS_DMA_H_

#include <linux/dmaengine.h>

#define MXS_DMA_CTRL_WAIT4END	BIT(31)
#define MXS_DMA_CTRL_WAIT4RDY	BIT(30)

/*
 * The mxs dmaengine can do PIO transfers. We pass a pointer to the PIO words
 * in the second argument to dmaengine_prep_slave_sg when the direction is
 * set to DMA_TRANS_NONE. To make this clear and to prevent users from doing
 * the error prone casting we have this wrapper function
 */
static inline struct dma_async_tx_descriptor *mxs_dmaengine_prep_pio(
        struct dma_chan *chan, u32 *pio, unsigned int npio,
        enum dma_transfer_direction dir, unsigned long flags)
{
	return dmaengine_prep_slave_sg(chan, (struct scatterlist *)pio, npio,
				       dir, flags);
}

#endif /* _MXS_DMA_H_ */

Annotation

Implementation Notes