Experience shows that, on the Armada platform, it can take as much as 120ms for the DMA engine to actually shut down after it has been told to. So a 40ms timeout is not adequate; use 150ms instead. Also make sure we don't leave the DMA_ACTIVE flag set once things are down. Signed-off-by: Jonathan Corbet <corbet@xxxxxxx> --- drivers/media/video/marvell-ccic/mcam-core.c | 10 +++++++++- 1 file changed, 9 insertions(+), 1 deletion(-) diff --git a/drivers/media/video/marvell-ccic/mcam-core.c b/drivers/media/video/marvell-ccic/mcam-core.c index b261182..050724f 100644 --- a/drivers/media/video/marvell-ccic/mcam-core.c +++ b/drivers/media/video/marvell-ccic/mcam-core.c @@ -742,7 +742,14 @@ static void mcam_ctlr_stop_dma(struct mcam_camera *cam) mcam_ctlr_stop(cam); cam->state = S_IDLE; spin_unlock_irqrestore(&cam->dev_lock, flags); - msleep(40); + /* + * This is a brutally long sleep, but experience shows that + * it can take the controller a while to get the message that + * it needs to stop grabbing frames. In particular, we can + * sometimes (on mmp) get a frame at the end WITHOUT the + * start-of-frame indication. + */ + msleep(150); if (test_bit(CF_DMA_ACTIVE, &cam->flags)) cam_err(cam, "Timeout waiting for DMA to end\n"); /* This would be bad news - what now? */ @@ -885,6 +892,7 @@ static int mcam_read_setup(struct mcam_camera *cam) * Turn it loose. */ spin_lock_irqsave(&cam->dev_lock, flags); + clear_bit(CF_DMA_ACTIVE, &cam->flags); mcam_reset_buffers(cam); mcam_ctlr_irq_enable(cam); cam->state = S_STREAMING; -- 1.7.9.3 -- To unsubscribe from this list: send the line "unsubscribe linux-media" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
