kernel-fxtec-pro1x/include/linux/dma/pxa-dma.h
Robert Jarzmik b6d1a17f47 dmaengine: pxa: document pxad_param
Add some documentation for the pxad_param structure, and describe the
contract behind the minimal required priority of a DMA channel.

Signed-off-by: Robert Jarzmik <robert.jarzmik@free.fr>
Acked-by: Vinod Koul <vkoul@kernel.org>
2018-06-18 21:32:15 +02:00

37 lines
837 B
C

/* SPDX-License-Identifier: GPL-2.0 */
#ifndef _PXA_DMA_H_
#define _PXA_DMA_H_
enum pxad_chan_prio {
PXAD_PRIO_HIGHEST = 0,
PXAD_PRIO_NORMAL,
PXAD_PRIO_LOW,
PXAD_PRIO_LOWEST,
};
/**
* struct pxad_param - dma channel request parameters
* @drcmr: requestor line number
* @prio: minimal mandatory priority of the channel
*
* If a requested channel is granted, its priority will be at least @prio,
* ie. if PXAD_PRIO_LOW is required, the requested channel will be either
* PXAD_PRIO_LOW, PXAD_PRIO_NORMAL or PXAD_PRIO_HIGHEST.
*/
struct pxad_param {
unsigned int drcmr;
enum pxad_chan_prio prio;
};
struct dma_chan;
#ifdef CONFIG_PXA_DMA
bool pxad_filter_fn(struct dma_chan *chan, void *param);
#else
static inline bool pxad_filter_fn(struct dma_chan *chan, void *param)
{
return false;
}
#endif
#endif /* _PXA_DMA_H_ */