[PATCH 4.4 030/162] dmaengine: coh901318: Fix a double-lock bug

[Greg Kroah-Hartman]

From: Jia-Ju Bai <baijiaju1990@xxxxxxxxx>

[ Upstream commit 627469e4445b9b12e0229b3bdf8564d5ce384dd7 ]

The function coh901318_alloc_chan_resources() calls spin_lock_irqsave()
before calling coh901318_config().
But coh901318_config() calls spin_lock_irqsave() again in its
definition, which may cause a double-lock bug.

Because coh901318_config() is only called by
coh901318_alloc_chan_resources(), the bug fix is to remove the
calls to spin-lock and -unlock functions in coh901318_config().

Signed-off-by: Jia-Ju Bai <baijiaju1990@xxxxxxxxx>
Reviewed-by: Linus Walleij <linus.walleij@xxxxxxxxxx>
Signed-off-by: Vinod Koul <vkoul@xxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
 drivers/dma/coh901318.c |    4 ----
 1 file changed, 4 deletions(-)

--- a/drivers/dma/coh901318.c
+++ b/drivers/dma/coh901318.c
@@ -1815,8 +1815,6 @@ static int coh901318_config(struct coh90
 	int channel = cohc->id;
 	void __iomem *virtbase = cohc->base->virtbase;
 
-	spin_lock_irqsave(&cohc->lock, flags);
-
 	if (param)
 		p = param;
 	else
@@ -1836,8 +1834,6 @@ static int coh901318_config(struct coh90
 	coh901318_set_conf(cohc, p->config);
 	coh901318_set_ctrl(cohc, p->ctrl_lli_last);
 
-	spin_unlock_irqrestore(&cohc->lock, flags);
-
 	return 0;
 }