dma: fix ipu_idmac.c to not discard the last queued buffer

This also fixes the case of a single queued buffer, for example, when taking a
single frame snapshot with the mx3_camera driver.

Reported-by: Agustin Ferrin Pozuelo <gatoguan-os@yahoo.com>
Tested-by: Agustin Ferrin Pozuelo <gatoguan-os@yahoo.com>
Signed-off-by: Guennadi Liakhovetski <g.liakhovetski@gmx.de>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>

1 files changed, 2 insertions, 1 deletions

diff --git a/drivers/dma/ipu/ipu_idmac.c b/drivers/dma/ipu/ipu_idmac.c
index 3a4deea78a71..9a5bc1a7389e 100644
--- a/drivers/dma/ipu/ipu_idmac.c
+++ b/drivers/dma/ipu/ipu_idmac.c
@@ -1272,7 +1272,8 @@ static irqreturn_t idmac_interrupt(int irq, void *dev_id)
         /* Other interrupts do not interfere with this channel */
         spin_lock(&ichan->lock);
         if (unlikely(chan_id != IDMAC_SDC_0 && chan_id != IDMAC_SDC_1 &&
-                     ((curbuf >> chan_id) & 1) == ichan->active_buffer)) {
+                     ((curbuf >> chan_id) & 1) == ichan->active_buffer &&
+                     !list_is_last(ichan->queue.next, &ichan->queue))) {
                 int i = 100;
 
                 /* This doesn't help. See comment in ipu_disable_channel() */