add LTC (linear timecode) read function via proc interface to the pcxhr driver
Signed-off-by: NMarkus Bollinger <bollinger@digigram.com>
Signed-off-by: NTakashi Iwai <tiwai@suse.de>

- add support for gpio ports (2 GPI, 2 GPO) of pcxhr stereo cards
- minor bugfixes : allow setting clock to internal by the mixer
                   even if there is no stream (but monitoring)
Signed-off-by: NMarkus Bollinger <bollinger@digigram.com>
Signed-off-by: NTakashi Iwai <tiwai@suse.de>

- add support for pcxhr stereo cards mixer controls
- adjust tlv db scales to real dBu values
- fix bug with monitoring volume control pcxhr_monitor_vol_put
- do some cleanup
Signed-off-by: NMarkus Bollinger <bollinger@digigram.com>
Signed-off-by: NTakashi Iwai <tiwai@suse.de>