From 5b2aa9f918f6837ae943557f8cec02c34fcf80e7 Mon Sep 17 00:00:00 2001
From: Peter Ujfalusi <peter.ujfalusi@ti.com>
Date: Thu, 6 Aug 2020 13:49:28 +0300
Subject: [PATCH] dmaengine: of-dma: Fix of_dma_router_xlate's of_dma_xlate handling
Git-commit: 5b2aa9f918f6837ae943557f8cec02c34fcf80e7
Patch-mainline: v5.9-rc4
References: git-fixes

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>
Acked-by: Takashi Iwai <tiwai@suse.de>

---
 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 863f2aaf5c8f..8a4f608904b9 100644
--- 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;
 	}
 
 	/*
-- 
2.16.4