diff options
| -rw-r--r-- | drivers/dma/dw/core.c | 29 |
1 files changed, 11 insertions, 18 deletions
diff --git a/drivers/dma/dw/core.c b/drivers/dma/dw/core.c index 87516246c445..e3749ec99016 100644 --- a/drivers/dma/dw/core.c +++ b/drivers/dma/dw/core.c @@ -901,25 +901,18 @@ bool dw_dma_filter(struct dma_chan *chan, void *param) } EXPORT_SYMBOL_GPL(dw_dma_filter); -/* - * 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) - */ -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); + struct dma_slave_config *sc = &dwc->dma_sconfig; + /* + * 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 DesignWare controller. + */ + 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; } |