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author | Yoshihiro Shimoda <yoshihiro.shimoda.uh@renesas.com> | 2019-09-09 09:34:52 +0300 |
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committer | Vinod Koul <vkoul@kernel.org> | 2019-10-14 09:56:58 +0300 |
commit | fcf8adb787073ba6c673c1bb9900a059c7f6676f (patch) | |
tree | 2bb9fb0072a8c6a84376842e7bf6f8846b22b998 /drivers/dma/sh | |
parent | d832c481bff39a28eb7e9b28485b749cab6b29b3 (diff) | |
download | linux-fcf8adb787073ba6c673c1bb9900a059c7f6676f.tar.xz |
dmaengine: rcar-dmac: Add dma-channel-mask property support
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@renesas.com>
Reviewed-by: Simon Horman <horms+renesas@verge.net.au>
Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be>
Link: https://lore.kernel.org/r/1568010892-17606-5-git-send-email-yoshihiro.shimoda.uh@renesas.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>
Diffstat (limited to 'drivers/dma/sh')
-rw-r--r-- | drivers/dma/sh/rcar-dmac.c | 10 |
1 files changed, 9 insertions, 1 deletions
diff --git a/drivers/dma/sh/rcar-dmac.c b/drivers/dma/sh/rcar-dmac.c index 542786de69a9..f06016d38a05 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; } |