media: rcar-vin: sync which hardware buffer to start capture from

[linux-2.6-microblaze.git] / drivers / media / platform / rcar-vin / rcar-dma.c

diff --git a/drivers/media/platform/rcar-vin/rcar-dma.c b/drivers/media/platform/rcar-vin/rcar-dma.c
index ac07f99..cfe5d7a 100644 (file)
--- a/drivers/media/platform/rcar-vin/rcar-dma.c
+++ b/drivers/media/platform/rcar-vin/rcar-dma.c
@@ -856,7 +856,7 @@ static int rvin_capture_start(struct rvin_dev *vin)
        /* Continuous Frame Capture Mode */
        rvin_write(vin, VNFC_C_FRAME, VNFC_REG);
 
-       vin->state = RUNNING;
+       vin->state = STARTING;
 
        return 0;
 }
@@ -910,6 +910,20 @@ static irqreturn_t rvin_irq(int irq, void *data)
        vnms = rvin_read(vin, VNMS_REG);
        slot = (vnms & VNMS_FBS_MASK) >> VNMS_FBS_SHIFT;
 
+       /*
+        * To hand buffers back in a known order to userspace start
+        * to capture first from slot 0.
+        */
+       if (vin->state == STARTING) {
+               if (slot != 0) {
+                       vin_dbg(vin, "Starting sync slot: %d\n", slot);
+                       goto done;
+               }
+
+               vin_dbg(vin, "Capture start synced!\n");
+               vin->state = RUNNING;
+       }
+
        /* Capture frame */
        if (vin->queue_buf[slot]) {
                vin->queue_buf[slot]->field = vin->format.field;