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 <yoshihiro.shimoda.uh@xxxxxxxxxxx> --- drivers/dma/sh/rcar-dmac.c | 12 +++++++++++- 1 file changed, 11 insertions(+), 1 deletion(-) diff --git a/drivers/dma/sh/rcar-dmac.c b/drivers/dma/sh/rcar-dmac.c index 204160e..bae0fe8 100644 --- a/drivers/dma/sh/rcar-dmac.c +++ b/drivers/dma/sh/rcar-dmac.c @@ -1806,7 +1806,17 @@ static int rcar_dmac_parse_of(struct device *dev, struct rcar_dmac *dmac) return -EINVAL; } - dmac->channels_mask = GENMASK(dmac->n_channels - 1, 0); + /* + * If the driver is unable to read dma-channel-mask property, + * the driver assumes that it can use all channels. + */ + ret = of_property_read_u32(np, "dma-channel-mask", + &dmac->channels_mask); + if (ret < 0) + dmac->channels_mask = GENMASK(dmac->n_channels - 1, 0); + + /* 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
