Commit be242f4e authored by Andy Shevchenko's avatar Andy Shevchenko Committed by Vinod Koul
Browse files

dmaengine: dw: replace convert_burst() with one liner 



Replace convert_burst() with one liner in place.

The change simplifies further extension of the driver to cover new DMA
controller hardware.

Signed-off-by: default avatarAndy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: default avatarVinod Koul <vinod.koul@intel.com>
parent 08d62f58

drivers/dma/dw/core.c

+11 −18
Original line number Diff line number Diff line
@@ -901,25 +901,18 @@ bool dw_dma_filter(struct dma_chan *chan, void *param) 
}

EXPORT_SYMBOL_GPL(dw_dma_filter);



static int dwc_config(struct dma_chan *chan, struct dma_slave_config *sconfig)

{

	struct dw_dma_chan *dwc = to_dw_dma_chan(chan);

	struct dma_slave_config *sc = &dwc->dma_sconfig;

	/*

 * Fix sconfig's burst size according to dw_dmac. We need to convert them as:

	 * Fix sconfig's burst size according to dw_dmac. We need to convert

	 * them as:

	 * 1 -> 0, 4 -> 1, 8 -> 2, 16 -> 3.

	 *

 * NOTE: burst size 2 is not supported by controller.

 *

 * This can be done by finding least significant bit set: n & (n - 1)

	 * NOTE: burst size 2 is not supported by DesignWare controller.

	 */

static inline void convert_burst(u32 *maxburst)

{

	if (*maxburst > 1)

		*maxburst = fls(*maxburst) - 2;

	else

		*maxburst = 0;

}



static int dwc_config(struct dma_chan *chan, struct dma_slave_config *sconfig)

{

	struct dw_dma_chan *dwc = to_dw_dma_chan(chan);

	u32 s = 2;



	/* Check if chan will be configured for slave transfers */

	if (!is_slave_direction(sconfig->direction))
@@ -928,8 +921,8 @@ static int dwc_config(struct dma_chan *chan, struct dma_slave_config *sconfig) 
	memcpy(&dwc->dma_sconfig, sconfig, sizeof(*sconfig));

	dwc->direction = sconfig->direction;



	convert_burst(&dwc->dma_sconfig.src_maxburst);

	convert_burst(&dwc->dma_sconfig.dst_maxburst);

	sc->src_maxburst = sc->src_maxburst > 1 ? fls(sc->src_maxburst) - s : 0;

	sc->dst_maxburst = sc->dst_maxburst > 1 ? fls(sc->dst_maxburst) - s : 0;



	return 0;

}