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>

diff --git a/drivers/dma/amba-pl08x.c b/drivers/dma/amba-pl08x.c
index b3b3180ce561c1073210db69dba4227c124e2b52..9a8d44504c6aab32e0a364287052ecd87c8ff8e5 100644 (file)
--- 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)) {