dmaengine: dw: replace convert_burst() with one liner (be242f4e) · Commits · 戴 / test

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;
		}