Hi Sakamoto-san > Could I request you to explain about usage of this lock primitive in SoC > with a few cores (i.e. 2) when dts allows the driver to handle several > PCM substreams and userspace applications try to use the PCM substreams > almost the same time? > http://git.kernel.org/cgit/linux/kernel/git/tiwai/sound.git/tree/sound/soc/sh/rcar/core.c#n501 Your concern is that my driver is using "trigger", and it will be called from several context. Indeed, one side might be locked if few substreams are used in same time, because it is using shared lock. But, I think I need to use it since it is using shared register. And, I'm confusing that what is the problem in this case ? Do you mean I shoudn't use "trigger" ? _______________________________________________ Alsa-devel mailing list Alsa-devel@xxxxxxxxxxxxxxxx http://mailman.alsa-project.org/mailman/listinfo/alsa-devel