diff mbox

[4/4] pxa_camera: Fix overrun condition on last buffer

Message ID 1236282351-28471-5-git-send-email-robert.jarzmik@free.fr (mailing list archive)
State Superseded, archived
Headers

Commit Message

Robert Jarzmik March 5, 2009, 7:45 p.m. UTC 
  The last buffer queued will often overrun, as the DMA chain
is finished, and the time the dma irq handler is activated,
the QIF fifos are filled by the sensor.

The fix is to ignore the overrun condition on the last
queued buffer, and restart the capture only on intermediate
buffers of the chain.

Signed-off-by: Robert Jarzmik <robert.jarzmik@free.fr>
---
 drivers/media/video/pxa_camera.c |    8 ++++++--
 1 files changed, 6 insertions(+), 2 deletions(-)
diff mbox

Patch

diff --git a/drivers/media/video/pxa_camera.c b/drivers/media/video/pxa_camera.c
index 16bf0a3..dd56c35 100644
--- a/drivers/media/video/pxa_camera.c
+++ b/drivers/media/video/pxa_camera.c
@@ -734,14 +734,18 @@  static void pxa_camera_dma_irq(int channel, struct pxa_camera_dev *pcdev,
 		status & DCSR_ENDINTR ? "EOF " : "", vb, DDADR(channel));
 
 	if (status & DCSR_ENDINTR) {
-		if (camera_status & overrun) {
+		/*
+		 * It's normal if the last frame creates an overrun, as there
+		 * are no more DMA descriptors to fetch from QIF fifos
+		 */
+		if (camera_status & overrun
+		    && !list_is_last(pcdev->capture.next, &pcdev->capture)) {
 			dev_dbg(pcdev->dev, "FIFO overrun! CISR: %x\n",
 				camera_status);
 			pxa_camera_stop_capture(pcdev);
 			pxa_camera_start_capture(pcdev);
 			goto out;
 		}
-
 		buf->active_dma &= ~act_dma;
 		if (!buf->active_dma)
 			pxa_camera_wakeup(pcdev, vb, buf);