On 31. 08. 23 19:06, Curtis Malainey wrote:
Curtis Malainey | Chrome OS Audio Senior Software Engineer | cujomalainey@google.com | Sound Open Firmware Lead
On Sat, Aug 26, 2023 at 4:31 AM Jaroslav Kysela perex@perex.cz wrote:
On 24. 08. 23 23:33, cujomalainey@chromium.org wrote:
From: Curtis Malainey cujomalainey@chromium.org
Provide a UCM value to mark devices which are needed to be opened only for HW purposes but should not be consumed for userspace.
It would be probably better to describe this in the standard ALSA PCM API than UCM. If the device is special, applications without UCM should be also allowed to identify them.
JaroslavWould something like an additional device class and a format subclass be acceptable?
The device class extension sounds good.
I don't know details for the format extension - does app require to set hw_params ? If yes, is the goal to prevent standard applications to set the hw_params ? If no, the format bitmask may be set to zero, thus hw_params will always fail.
Jaroslav