Hi, On Wednesday 10 August 2011 16:03:12 Deepthy Ravi wrote: > From: Abhilash K V <abhilash.kv@xxxxxx> > > While resuming from the "suspended to memory" state, > occasionally CCDC fails to get enabled and thus fails > to capture frames any more till the next suspend/resume > is issued. > This is a race condition which happens only when a CCDC > frame-completion ISR is pending even as ISP device's > isp_pm_prepare() is getting called and only one buffer > is left on the DMA queue. > The DMA queue buffers are thus depleted which results in > its underrun.So when ISP resumes there are no buffers on > the queue (as the application which can issue buffers is > yet to resume) to start video capture. > This fix addresses this issue by dequeuing and enqueing > the last buffer in isp_pm_prepare() after its DMA gets > completed. Thus,when ISP resumes it always finds atleast > one buffer on the DMA queue - this is true if application > uses only 3 buffers. How is that problem specific to the CCDC ? Can't it be reproduce at the preview engine or resizer output as well ? -- Regards, Laurent Pinchart -- 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
