ALSA: hdspm - Enable AD/DA/PH gains and S/PDIF-Input select on AIO

This patch uses the newly introduced HDSPM_CONTROL_TRISTATE functions to
create and expose the following ALSA controls:

   - Gain selection for Input, Output and Phones (HiGain, +4dBu, -10dbV)
   - S/PDIF Input select (Coaxial, Optical, Internal)

Signed-off-by: Adrian Knoth <adi@drcomp.erfurt.thur.de>
Signed-off-by: Takashi Iwai <tiwai@suse.de>

sound/pci/rme9652/hdspm.c

@@ -4412,11 +4412,15 @@ static struct snd_kcontrol_new snd_hdspm_controls_aio[] = {
 	HDSPM_AUTOSYNC_SAMPLE_RATE("ADAT Frequency", 3),
 	HDSPM_AUTOSYNC_SAMPLE_RATE("TCO Frequency", 4),
 	HDSPM_AUTOSYNC_SAMPLE_RATE("SYNC IN Frequency", 5),
+	HDSPM_CONTROL_TRISTATE("S/PDIF Input", HDSPM_c0_Input0),
 	HDSPM_TOGGLE_SETTING("S/PDIF Out Optical", HDSPM_c0_Spdif_Opt),
 	HDSPM_TOGGLE_SETTING("S/PDIF Out Professional", HDSPM_c0_Pro),
 	HDSPM_TOGGLE_SETTING("ADAT internal (AEB/TEB)", HDSPM_c0_AEB1),
 	HDSPM_TOGGLE_SETTING("XLR Breakout Cable", HDSPM_c0_Sym6db),
-	HDSPM_TOGGLE_SETTING("Single Speed WordClock Out", HDSPM_c0_Wck48)
+	HDSPM_TOGGLE_SETTING("Single Speed WordClock Out", HDSPM_c0_Wck48),
+	HDSPM_CONTROL_TRISTATE("Input Level", HDSPM_c0_AD_GAIN0),
+	HDSPM_CONTROL_TRISTATE("Output Level", HDSPM_c0_DA_GAIN0),
+	HDSPM_CONTROL_TRISTATE("Phones Level", HDSPM_c0_PH_GAIN0)
 
 		/*
 		   HDSPM_INPUT_SELECT("Input Select", 0),