From 1bb0739acfc9bbfe61ffaf4707ea9a9d98cdb82b Mon Sep 17 00:00:00 2001
From: Jaroslav Kysela <perex@perex.cz>
Date: Thu, 4 Dec 2025 16:26:23 +0100
Subject: [PATCH] USB-Audio: add support for conf.d configurations

It may be useful to add new or override specific hardware
configurations until they are merged to the main USB-Audio.conf file.

Closes: https://github.com/alsa-project/alsa-ucm-conf/pull/654
BugLink: https://github.com/alsa-project/alsa-ucm-conf/issues/609
Signed-off-by: Jaroslav Kysela <perex@perex.cz>
---
 ucm2/USB-Audio/USB-Audio.conf | 21 +++++++++++++++++++++
 1 file changed, 21 insertions(+)

diff --git a/ucm2/USB-Audio/USB-Audio.conf b/ucm2/USB-Audio/USB-Audio.conf
index fe840fa..7f7d865 100644
--- a/ucm2/USB-Audio/USB-Audio.conf
+++ b/ucm2/USB-Audio/USB-Audio.conf
@@ -1,8 +1,16 @@
 Syntax 8
 
+#
+# Optional configuration can be stored to USB-Audio/conf.d/{VENDOR}-{DEVICE}.conf files
+#
+
 Define.ProfileName ""
 Define.MixerRemap ""
 Define.SplitPCMPeriodTime 10000		# 10ms
+DefineRegex.USBID {
+	Regex "USB([0-9a-f]{4}):([0-9a-f]{4})"
+	String "${CardComponents}"
+}
 
 If.env1 {
 	Condition {
@@ -12,6 +20,10 @@ If.env1 {
 	False.Define.SplitPCMPeriodTime "${env:UCM_USB_PERIOD_TIME}"
 }
 
+#
+# device specific configuration block
+#
+
 If.linked {
 	Condition {
 		Type RegexMatch
@@ -616,6 +628,15 @@ If.beacn-studio {
 	True.Define.ProfileName "Beacn/Beacn-Studio"
 }
 
+#
+# end of device specific configuration block
+#
+
+If.opt.Append.Include.opt {
+	File "/USB-Audio/conf.d/${var:USBID1}-${var:USBID2}.conf"
+	Optional true
+}
+
 If.mixremap {
 	Condition {
 		Type String
-- 
2.47.3