[PATCH 5.15.y] dmaengine: stm32: dmamux: fix OF node leak on route allocation failure

[Sasha Levin <sashal@kernel.org>]

From: Johan Hovold <johan@kernel.org>

[ Upstream commit b1b590a590af13ded598e70f0b72bc1e515787a1 ]

Make sure to drop the reference taken to the DMA master OF node also on
late route allocation failures.

Fixes: df7e762db5f6 ("dmaengine: Add STM32 DMAMUX driver")
Cc: stable@vger.kernel.org      # 4.15
Cc: Pierre-Yves MORDRET <pierre-yves.mordret@foss.st.com>
Signed-off-by: Johan Hovold <johan@kernel.org>
Reviewed-by: Amelie Delaunay <amelie.delaunay@foss.st.com>
Link: https://patch.msgid.link/20251117161258.10679-12-johan@kernel.org
Signed-off-by: Vinod Koul <vkoul@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 drivers/dma/stm32-dmamux.c | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/drivers/dma/stm32-dmamux.c b/drivers/dma/stm32-dmamux.c
index d5d55732adba1..ef4240ec94974 100644
--- a/drivers/dma/stm32-dmamux.c
+++ b/drivers/dma/stm32-dmamux.c
@@ -140,7 +140,7 @@ static void *stm32_dmamux_route_allocate(struct of_phandle_args *dma_spec,
 	ret = pm_runtime_resume_and_get(&pdev->dev);
 	if (ret < 0) {
 		spin_unlock_irqrestore(&dmamux->lock, flags);
-		goto error;
+		goto err_put_dma_spec_np;
 	}
 	spin_unlock_irqrestore(&dmamux->lock, flags);
 
@@ -160,6 +160,8 @@ static void *stm32_dmamux_route_allocate(struct of_phandle_args *dma_spec,
 
 	return mux;
 
+err_put_dma_spec_np:
+	of_node_put(dma_spec->np);
 error:
 	clear_bit(mux->chan_id, dmamux->dma_inuse);
 
-- 
2.51.0