Hi,
this is a revised patchset for supporting the explicit appl_ptr update. Since the protocol version from user-space needs to be stored locally for each opened file, the check of status/control mmap was slightly changed as well. But the basic strategy is same as the previous patchset.
Note that this patchset doesn't solve the issue that appl_ptr update isn't properly notified to ack ops as Sakamoto-san pointed out previously. We'll still need to sort it out. But the hack I introduced here doesn't basically conflict with it, and it'll even make it easier to solve later, by the new USER_PVERSION ioctl.
thanks,
Takashi
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Takashi Iwai (3): ALSA: pcm: Add the explicit appl_ptr sync support ALSA: pcm: Add an ioctl to specify the supported protocol version ALSA: pcm: Limit the appl_ptr sync workaround only for old user-space
include/sound/pcm.h | 1 + include/uapi/sound/asound.h | 4 +++- sound/core/pcm_compat.c | 1 + sound/core/pcm_native.c | 34 ++++++++++++++++++++++++++++++++-- 4 files changed, 37 insertions(+), 3 deletions(-)