USB-Audio: Improve support for Focusrite 4th Gen devices

There are 4 capture channels (additional ones for mixer monitor).

Closes: #515
Closes: #516
Signed-off-by: Jaroslav Kysela <perex@perex.cz>

Author: perexg

ucm2/USB-Audio/Focusrite/Scarlett-2i-HiFi.conf

@@ -1,20 +1,42 @@
 Include.pcm_split.File "/common/pcm/split.conf"
 
-Macro [
-	{
-		SplitPCM {
-			Name "scarlett2i_mono_in"
-			Direction Capture
-			Format S32_LE
-			Channels 1
-			HWChannels 2
-			HWChannelPos0 MONO
-			HWChannelPos1 MONO
-		}
+If.cch4 {
+	Condition {
+		Type String
+		String1 "${var:CaptureChannels}"
+		String2 "4"
 	}
-]
+	True.Macro [
+		{
+			SplitPCM {
+				Name "scarlett2i_mono_in"
+				Direction Capture
+				Format S32_LE
+				Channels 1
+				HWChannels 4
+				HWChannelPos0 MONO
+				HWChannelPos1 MONO
+				HWChannelPos2 MONO
+				HWChannelPos3 MONO
+			}
+		}
+	]
+	False.Macro [
+		{
+			SplitPCM {
+				Name "scarlett2i_mono_in"
+				Direction Capture
+				Format S32_LE
+				Channels 1
+				HWChannels 2
+				HWChannelPos0 MONO
+				HWChannelPos1 MONO
+			}
+		}
+	]
+}
 
-If.2i4 {
+If.pch4 {
 	Condition {
 		Type String
 		String1 "${var:PlaybackChannels}"
@@ -65,7 +87,7 @@ SectionDevice."Line1" {
 	}
 }
 
-If.2i4 {
+If.line2 {
 	Condition {
 		Type String
 		String1 "${var:PlaybackChannels}"
@@ -94,12 +116,12 @@ SectionDevice."Mic1" {
 	Comment "${var:Capture1Name}"
 
 	Value {
-		CapturePriority 200
+		CapturePriority 400
 	}
 	Macro.pcm_split.SplitPCMDevice {
 		Name "scarlett2i_mono_in"
 		Direction Capture
-		HWChannels 2
+		HWChannels "${var:CaptureChannels}"
 		Channels 1
 		Channel0 0
 		ChannelPos0 MONO
@@ -110,14 +132,55 @@ SectionDevice."Mic2" {
 	Comment "${var:Capture2Name}"
 
 	Value {
-		CapturePriority 100
+		CapturePriority 300
 	}
 	Macro.pcm_split.SplitPCMDevice {
 		Name "scarlett2i_mono_in"
 		Direction Capture
-		HWChannels 2
+		HWChannels "${var:CaptureChannels}"
 		Channels 1
 		Channel0 1
 		ChannelPos0 MONO
 	}
 }
+
+If.cap4 {
+	Condition {
+		Type String
+		String1 "${var:CaptureChannels}"
+		String2 "4"
+	}
+	True {
+		SectionDevice."Line3" {
+			Comment "${var:Capture3Name}"
+
+			Value {
+				CapturePriority 200
+			}
+			Macro.pcm_split.SplitPCMDevice {
+				Name "scarlett2i_mono_in"
+				Direction Capture
+				HWChannels "${var:CaptureChannels}"
+				Channels 1
+				Channel0 0
+				ChannelPos0 MONO
+			}
+		}
+
+		SectionDevice."Line4" {
+			Comment "${var:Capture4Name}"
+
+			Value {
+				CapturePriority 100
+			}
+			Macro.pcm_split.SplitPCMDevice {
+				Name "scarlett2i_mono_in"
+				Direction Capture
+				HWChannels "${var:CaptureChannels}"
+				Channels 1
+				Channel0 1
+				ChannelPos0 MONO
+			}
+		}
+	}
+}

ucm2/USB-Audio/Focusrite/Scarlett-2i.conf

@@ -1,7 +1,6 @@
 Define {
 	PlaybackChannels 2
-	DirectPlaybackChannels 2
-	DirectCaptureChannels 2
+	CaptureChannels 2
 	Model "2i2"
 	Playback1Name "Headphones / Line 1-2"
 	Playback2Name "Line 3-4"
@@ -61,7 +60,12 @@ If.gen4 {
 		String "${CardComponents}"
 		Regex "USB1235:821[89]"
 	}
-	True.Define.Generation "4th"
+	True.Define {
+		Generation "4th"
+		CaptureChannels 4
+		Capture3Name "Input 3 Monitor"
+		Capture4Name "Input 4 Monitor"
+	}
 }
 
 Comment "Focusrite Scarlett ${var:Model} ${var:Generation} Gen"
@@ -71,4 +75,12 @@ SectionUseCase."HiFi" {
 	File "/USB-Audio/Focusrite/Scarlett-2i-HiFi.conf"
 }
 
+If.dhw {
+	Condition { Type AlwaysTrue }
+	True.Define {
+		DirectPlaybackChannels "${var:PlaybackChannels}"
+		DirectCaptureChannels "${var:CaptureChannels}"
+	}
+}
+
 Include.dhw.File "/common/direct.conf"