dmaengine: of-dma: Fix of_dma_router_xlate's of_dma_xlate handling

[ 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@ti.com>
Link: https://lore.kernel.org/r/20200806104928.25975-1-peter.ujfalusi@ti.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>

diff --git a/drivers/dma/of-dma.c b/drivers/dma/of-dma.c
index b2c2b5e8093cf0d7c64898e06be41f3b79e0f76b..0db816eb8080db32c60d21b441540318f1a1a7d9 100644 (file)
--- a/drivers/dma/of-dma.c
+++ b/drivers/dma/of-dma.c
@@ -71,12 +71,12 @@ 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;
        }
 
        /*