On Tue, 02 May 2023 13:55:36 +0200, Jaroslav Kysela wrote: > > Introduce SNDRV_PCM_INFO_PERFECT_DRAIN and SNDRV_PCM_HW_PARAMS_NO_DRAIN_SILENCE > flags to fully control the filling of the silence samples in the drain ioctl. > Actually, the configurable silencing is going to be implemented in the user > space [1], but drivers (hardware) may not require this operation. Those flags > do the bidirectional setup for this operation: > > 1) driver may notify the presence of the perfect drain > 2) user space may not require the filling of the silence samples to inhibit clicks > > If we decide to move this operation to the kernel space in future, the > SNDRV_PCM_INFO_PERFECT_DRAIN flag may handle this situation without > double "silence" processing (user + kernel space). > > The ALSA API should be universal, so forcing the behaviour (modifying of > the ring buffer with any samples) for the drain operation is not ideal. > > [1] https://lore.kernel.org/alsa-devel/20230502115010.986325-1-perex@xxxxxxxx/ > > Signed-off-by: Jaroslav Kysela <perex@xxxxxxxx> Now applied to for-next branch (with a typo fix in the comment). thanks, Takashi
