This patch adds dma-channel-mask property support not to reserve some DMA channels for some reasons. (for example: a heterogeneous CPU uses it.)
Signed-off-by: Yoshihiro Shimoda <[email protected]> Reviewed-by: Simon Horman <[email protected]> Reviewed-by: Geert Uytterhoeven <[email protected]> --- drivers/dma/sh/rcar-dmac.c | 10 +++++++++- 1 file changed, 9 insertions(+), 1 deletion(-) diff --git a/drivers/dma/sh/rcar-dmac.c b/drivers/dma/sh/rcar-dmac.c index 542786d..f06016d 100644 --- a/drivers/dma/sh/rcar-dmac.c +++ b/drivers/dma/sh/rcar-dmac.c @@ -203,7 +203,7 @@ struct rcar_dmac { unsigned int n_channels; struct rcar_dmac_chan *channels; - unsigned int channels_mask; + u32 channels_mask; DECLARE_BITMAP(modules, 256); }; @@ -1810,7 +1810,15 @@ static int rcar_dmac_parse_of(struct device *dev, struct rcar_dmac *dmac) return -EINVAL; } + /* + * If the driver is unable to read dma-channel-mask property, + * the driver assumes that it can use all channels. + */ dmac->channels_mask = GENMASK(dmac->n_channels - 1, 0); + of_property_read_u32(np, "dma-channel-mask", &dmac->channels_mask); + + /* If the property has out-of-channel mask, this driver clears it */ + dmac->channels_mask &= GENMASK(dmac->n_channels - 1, 0); return 0; } -- 2.7.4
