2010/11/5 Michael Jones <michael.jo...@matrix-vision.de>: > Hi Bastian (Laurent, and Sakari), >> >> I want to clarify this: >> >> I try to read images with yafta. >> I read in 4 images with 5MP size (no skipping). All 4 images contain only >> zeros. >> I repeat the process some times and keep checking the data. After - >> let's say the 6th time - the images contain exactly the data I expect. >> WHEN they are read they are good. I just don't want to read 20 black >> images before 1 image is transferred right. >> >> -Bastian >> > > I'm on to your problem, having reproduced it myself. I suspect that you're > actually only getting one frame: your very first buffer. You don't touch it, > and neither does the CCDC after you requeue it, and after you've cycled > through all your other buffers, you get back the non-zero frame. If you > clear the "good" frame in your application once, you won't get any more > non-zero frames afterwards. Or if you request more buffers, you'll have > fewer non-zero frames. That's the behavior I observe.
I can confirm the very first buffer theorem. I indeed get 1 valid frame after each reboot. First I didn'notice it because I used Laurent's yafta .... --skip 3 ... command line. I read 4 frames and only saved the last. Btw, heaven sent you... I keep working on this problem 1 week now and am pretty desperate. I started reading about the linux memory management system to understand all the buffer dma streaming. (well that is probably not the worst thing to sacrifice time...) Tell me if I can do something for you to help. cheers, Bastian > The CCDC is getting disabled by the VD1 interrupt: > ispccdc_vd1_isr()->__ispccdc_handle_stopping()->__ispccdc_enable(ccdc, 0) > > To test this theory I tried disabling the VD1 interrupt, but it didn't solve > the problem. In fact, I was still getting VD1 interrupts even though I had > disabled them. Has anybody else observed that VD1 cannot be disabled? > > I also found it strange that the CCDC seemed to continue to generate > interrupts when it's disabled. > > Here's my suggestion for a fix, hopefully Laurent or Sakari can comment on it: > > --- a/drivers/media/video/isp/ispccdc.c > +++ b/drivers/media/video/isp/ispccdc.c > @@ -1477,7 +1477,7 @@ static void ispccdc_vd1_isr(struct isp_ccdc_device > *ccdc) > spin_lock_irqsave(&ccdc->lsc.req_lock, flags); > > /* We are about to stop CCDC and/without LSC */ > - if ((ccdc->output & CCDC_OUTPUT_MEMORY) || > + if ((ccdc->output & CCDC_OUTPUT_MEMORY) && > (ccdc->state == ISP_PIPELINE_STREAM_SINGLESHOT)) > ccdc->stopping = CCDC_STOP_REQUEST; > > > -- > Michael Jones > > MATRIX VISION GmbH, Talstrasse 16, DE-71570 Oppenweiler > Registergericht: Amtsgericht Stuttgart, HRB 271090 > Geschaeftsfuehrer: Gerhard Thullner, Werner Armingeon, Uwe Furtner > -- To unsubscribe from this list: send the line "unsubscribe linux-media" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
