[PATCH 5.4 022/129] dmaengine: of-dma: Fix of_dma_router_xlates of_dma_xlate handling

From: Greg Kroah-Hartman
Date: Tue Sep 08 2020 - 14:21:57 EST


From: Peter Ujfalusi <peter.ujfalusi@xxxxxx>

[ Upstream commit 5b2aa9f918f6837ae943557f8cec02c34fcf80e7 ]

of_dma_xlate callback can return ERR_PTR as well NULL in case of failure.

If error code is returned (not NULL) then the route should be released and
the router should not be registered for the channel.

Fixes: 56f13c0d9524c ("dmaengine: of_dma: Support for DMA routers")
Signed-off-by: Peter Ujfalusi <peter.ujfalusi@xxxxxx>
Link: https://lore.kernel.org/r/20200806104928.25975-1-peter.ujfalusi@xxxxxx
Signed-off-by: Vinod Koul <vkoul@xxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
drivers/dma/of-dma.c | 8 ++++----
1 file changed, 4 insertions(+), 4 deletions(-)

diff --git a/drivers/dma/of-dma.c b/drivers/dma/of-dma.c
index c2d779daa4b51..4bbf4172b9bf9 100644
--- a/drivers/dma/of-dma.c
+++ b/drivers/dma/of-dma.c
@@ -69,12 +69,12 @@ static struct dma_chan *of_dma_router_xlate(struct of_phandle_args *dma_spec,
return NULL;

chan = ofdma_target->of_dma_xlate(&dma_spec_target, ofdma_target);
- if (chan) {
- chan->router = ofdma->dma_router;
- chan->route_data = route_data;
- } else {
+ if (IS_ERR_OR_NULL(chan)) {
ofdma->dma_router->route_free(ofdma->dma_router->dev,
route_data);
+ } else {
+ chan->router = ofdma->dma_router;
+ chan->route_data = route_data;
}

/*
--
2.25.1