Allow external control plugins to provide TLV data. This allows
user-space pcms to specify dB ranges for controls.
This follows the same model as the ALSA drivers for accessing the
data. The code is based on that implementation. The control can
provide static data or a callback. The data is accessed or modified
in the new snd_ctl_ext_elem_tlv callback.
Rev bump the protocol version to enable checking if an external
control supports TLV.
Signed-off-by: Dylan Reid <dgreid@chromium.org>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
So far, external ctl plugins don't change numid. Some apps expect the
non-zero numids with list, and the plugin doesn't work for them.
This patch adds a fake numid to each control based on the offset
number. The lookup with non-zero numid is supported but is pretty
inefficient. Eventually the plugin side may be optimized to look
at the numid, too.
Signed-off-by: Takashi Iwai <tiwai@suse.de>
int64_t and long long isn't strictly identical, and thus gcc gives us
a heartful warning. Suppress the warning by a pointer cast.
Signed-off-by: Takashi Iwai <tiwai@suse.de>
