ARM: PL08x: fix missed spin-unlock in pl08x_issue_pending()

pl08x_issue_pending() returns with the spinlock locked and interrupts
disabled if the channel is waiting for a physical DMA to become free.
This is wrong - especially as pl08x_issue_pending() is an API function
as it leads to deadlocks.  Fix it to always return with the spinlock
unlocked.

Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Acked-by: Linus Walleij <linus.walleij@stericsson.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>

1 files changed, 4 insertions, 8 deletions

diff --git a/drivers/dma/amba-pl08x.c b/drivers/dma/amba-pl08x.c
index b3b3180ce561..9a8d44504c6a 100644
--- a/drivers/dma/amba-pl08x.c
+++ b/drivers/dma/amba-pl08x.c
@@ -1294,15 +1294,11 @@ static void pl08x_issue_pending(struct dma_chan *chan)
         unsigned long flags;
 
         spin_lock_irqsave(&plchan->lock, flags);
-        /* Something is already active */
-        if (plchan->at) {
-                        spin_unlock_irqrestore(&plchan->lock, flags);
-                        return;
-        }
-
-        /* Didn't get a physical channel so waiting for it ... */
-        if (plchan->state == PL08X_CHAN_WAITING)
+        /* Something is already active, or we're waiting for a channel... */
+        if (plchan->at || plchan->state == PL08X_CHAN_WAITING) {
+                spin_unlock_irqrestore(&plchan->lock, flags);
                 return;
+        }
 
         /* Take the first element in the queue and execute it */
         if (!list_empty(&plchan->desc_list)) {