From 77e75fda94d2ebb86aa9d35fb1860f6395bf95de Mon Sep 17 00:00:00 2001
From: Richard Genoud <richard.genoud@gmail.com>
Date: Tue, 27 Nov 2018 17:06:35 +0100
Subject: [PATCH] dmaengine: at_hdmac: fix module unloading
Git-commit: 77e75fda94d2ebb86aa9d35fb1860f6395bf95de
Patch-mainline: v4.20-rc5
References: bsc#1051510
of_dma_controller_free() was not called on module onloading.
This lead to a soft lockup:
Watchdog: BUG: soft lockup - CPU#0 stuck for 23s!
Modules linked in: at_hdmac [last unloaded: at_hdmac]
when of_dma_request_slave_channel() tried to call ofdma->of_dma_xlate().
Cc: stable@vger.kernel.org
Fixes: bbe89c8e3d59 ("at_hdmac: move to generic DMA binding")
Acked-by: Ludovic Desroches <ludovic.desroches@microchip.com>
Signed-off-by: Richard Genoud <richard.genoud@gmail.com>
Signed-off-by: Vinod Koul <vkoul@kernel.org>
Acked-by: Takashi Iwai <tiwai@suse.de>
---
drivers/dma/at_hdmac.c | 2 ++
1 file changed, 2 insertions(+)
diff --git a/drivers/dma/at_hdmac.c b/drivers/dma/at_hdmac.c
index 1b7f0ca0d5cd..01d936c9fe89 100644
--- a/drivers/dma/at_hdmac.c
+++ b/drivers/dma/at_hdmac.c
@@ -2006,6 +2006,8 @@ static int at_dma_remove(struct platform_device *pdev)
struct resource *io;
at_dma_off(atdma);
+ if (pdev->dev.of_node)
+ of_dma_controller_free(pdev->dev.of_node);
dma_async_device_unregister(&atdma->dma_common);
dma_pool_destroy(atdma->memset_pool);
--
2.16.4