On Wed, 17 Jun 2020 12:14:42 +0100 (BST) Mark Hills mark@xwax.org wrote:
On Wed, 17 Jun 2020, Giuliano Pochini wrote: [...]
- pipe->position += step; /* bytes */
- buffer_bytes = frames_to_bytes(runtime, runtime->buffer_size);
- while (pipe->position >= buffer_bytes)
pipe->position -= buffer_bytes;- return 1;
I think this risks returning to a case where it concludes nothing advances if the counter advances by a whole buffer?
Yes, it can, but you can detect that case checking for step >= period_bytes.
You might be able to do the comparison before wrapping pipe_position, but hopefully you'll consider my patch in reply to Takashi has more clarity.
Your patch is very interesting. I didn't take into account the idea of advancing the position by full periods only. If the PCM subsystem hasn't changed much since I last checked (I wrote the driver many years ago), it should work fine (and I'm sure you tested it). But I don't know if something else requires better resolution.