Hello Clemens,
When there are multiple clients, there are multiple appl pointers. So the dmix plugin does not bother to tell the hardware about any of them.
Thanks,Understood.
Are you using a driver that lokos at appl_ptr?
We are working on Marvell chipset,88DE3006. Looks like our driver looks at appl_pointer though I am not sure how to confirm it. I see the appl_pointer coming through SNDRV_PCM_IOCTL_SYNC_PTR is always incremented in case of aplay -M and it works, if we don't increment appl_ptr it doesn't works,
So for dmix to work, I should have the driver that doesn't looks at appl_ptr, right? f appl_pointer should never be incremented, how will the kernel know the data is written? The MMAP to status/control is not implemented in our case. I would start looking to change my driver not to look at appl_ptr, would you please help me with some pointers to understand how/where in drivers should I typically change to adapt these changes?
Regards, Anoop
On Thu, Jan 26, 2017 at 5:33 PM, Clemens Ladisch clemens@ladisch.de wrote:
Anoop Rajan wrote:
I assume the issue is in Dmix, it is not incrementing the appl pointer.
When there are multiple clients, there are multiple appl pointers. So the dmix plugin does not bother to tell the hardware about any of them.
Are you using a driver that lokos at appl_ptr?
Regards, Clemens