On Tue, 05 Nov 2019 15:32:18 +0100, Andrew Gabbasov wrote:
Show and change sound card timer source with read-write info file in proc filesystem. Initial string can still be set as module parameter.
The timer source string value can be changed at any time, but it is latched by PCM substream open callback (the first one for a particular cable). At this point it is actually used, that is the string is parsed, and the timer is looked up and opened.
The timer source is set for a loopback card (the same as initial setting by module parameter), but every cable uses the value, current at the moment of open.
Setting the value to empty string switches the timer to jiffies.
Signed-off-by: Andrew Gabbasov andrew_gabbasov@mentor.com
Unfortunately the whole code here are racy. It may lead to a crash or use-after-free easily. Some locking is needed definitely.
thanks,
Takashi