[PATCH] spi_dw_midpci: fix oops during modprobe -r

[Andy Shevchenko <andriy.shevchenko-VuQAYsv1563Yd54FQh9/CA@public.gmane.org>]

In case there were no DMA channel requested the modprobe -r spi_dw_midpci is
going to crash. This patch fixes an issue.

Signed-off-by: Andy Shevchenko <andriy.shevchenko-VuQAYsv1563Yd54FQh9/CA@public.gmane.org>
---
 drivers/spi/spi-dw-mid.c |    6 ++++--
 1 file changed, 4 insertions(+), 2 deletions(-)

diff --git a/drivers/spi/spi-dw-mid.c b/drivers/spi/spi-dw-mid.c
index b9f0192..4fac682 100644
--- a/drivers/spi/spi-dw-mid.c
+++ b/drivers/spi/spi-dw-mid.c
@@ -89,8 +89,10 @@ err_exit:
 
 static void mid_spi_dma_exit(struct dw_spi *dws)
 {
-	dma_release_channel(dws->txchan);
-	dma_release_channel(dws->rxchan);
+	if (dws->dma_inited) {
+		dma_release_channel(dws->txchan);
+		dma_release_channel(dws->rxchan);
+	}
 }
 
 /*
-- 
1.7.10.4


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