From 0d34c6c6eeb6159370db6e7dc85d730e562048c5 Mon Sep 17 00:00:00 2001 From: Xinyu Chen Date: Fri, 9 Dec 2011 14:47:57 +0800 Subject: [PATCH] ENGR00169891 v4l2 capture: avoid streamon with only one buffer queued If user space only queue one buffer into ready list, and call streamon, camera csi enc ISR will crash. Since for CSI ENC, the ping pong buffer is initilized without checking ready buffer on streamon. The second buffer will be wrongly in cam_data struct, and causes DMA fill buffers into cam_data global variable. Here just add one sanity check for ready buffer. Signed-off-by: Xinyu Chen --- drivers/media/video/mxc/capture/mxc_v4l2_capture.c | 6 ++++++ 1 file changed, 6 insertions(+) diff --git a/drivers/media/video/mxc/capture/mxc_v4l2_capture.c b/drivers/media/video/mxc/capture/mxc_v4l2_capture.c index a6045061f505..e4108c291c40 100644 --- a/drivers/media/video/mxc/capture/mxc_v4l2_capture.c +++ b/drivers/media/video/mxc/capture/mxc_v4l2_capture.c @@ -382,6 +382,12 @@ static int mxc_streamon(cam_data *cam) "queued yet\n"); return -EINVAL; } + if (cam->enc_update_eba && + cam->ready_q.prev == cam->ready_q.next) { + pr_err("ERROR: v4l2 capture: mxc_streamon buffer need ping pong " + "at least two buffers\n"); + return -EINVAL; + } cam->capture_pid = current->pid; -- 2.39.5