On Fri, 2012-08-31 at 12:41 +0200, Jaroslav Kysela wrote:
Date 31.8.2012 03:14, Vinod Koul wrote:
Old wine in a new bottle with added flavour now. Based on our discussions in LPC, now we will report the combined delay value as sum of the buffering done in driver and hardware. This is used to report delay
Additionally we tell pcm what is buffer in device/driver, this is used to check for error calulcations
I'm afraid, but this won't work for the mmaped appl_ptr / hw_ptr, because the checks are done outside the kernel - in alsa-lib. I believe that this API should be enhanced, too. But the question is, how to pass two values (hwptr, device_buffer) atomically to the user space without locks for x86.
Yes for mmap case, tis needs to be done in lib and that can't be done without ABI/API changes?? Is there a reserved field we can perhaps use for this