From 377bab0430f07144cc2b059e4e965f155095fa54 Mon Sep 17 00:00:00 2001
From: Wim Taymans <wtaymans@redhat.com>
Date: Thu, 18 Jun 2026 11:06:44 +0200
Subject: [PATCH] mixer-dsp: fade-in/out on xrun as well

When there is no input buffer because of an xrun or the io was removed,
ramp down the signal. Only remove the port from the mix list when the io
was removed, otherwise, ramp back up when there is a buffers on the
input again.

This avoids pops and click around xrun nodes.
---
 spa/plugins/audiomixer/mixer-dsp.c | 7 +++++--
 1 file changed, 5 insertions(+), 2 deletions(-)

diff --git a/spa/plugins/audiomixer/mixer-dsp.c b/spa/plugins/audiomixer/mixer-dsp.c
index d5e23b295..7278139b1 100644
--- a/spa/plugins/audiomixer/mixer-dsp.c
+++ b/spa/plugins/audiomixer/mixer-dsp.c
@@ -87,6 +87,7 @@ struct port {
 
 	struct spa_list mix_link;
 	bool active:1;
+	bool removing:1;
 	uint32_t ramp_pos;
 	float history[1];
 };
@@ -750,6 +751,7 @@ static int do_port_set_io(struct spa_loop *loop, bool async, uint32_t seq,
 	if (info->data == NULL || info->size < sizeof(struct spa_io_buffers)) {
 		port->io[0] = NULL;
 		port->io[1] = NULL;
+		port->removing = true;
 		port->ramp_pos = impl->n_curve;
 	} else {
 		if (info->size >= sizeof(struct spa_io_async_buffers)) {
@@ -760,6 +762,7 @@ static int do_port_set_io(struct spa_loop *loop, bool async, uint32_t seq,
 			port->io[0] = info->data;
 			port->io[1] = info->data;
 		}
+		port->removing = false;
 		port->ramp_pos = 0;
 		if (port->direction == SPA_DIRECTION_INPUT && !port->active) {
 			spa_list_append(&info->impl->mix_list, &port->mix_link);
@@ -843,7 +846,7 @@ static void ramp_down(struct impl *this, float *dst, uint32_t size, struct ramp_
 	for (c = port->ramp_pos, i = 0; i < size && c > 0; i++, c--)
 		dst[i] += last_sample * this->curve[c-1];
 	port->ramp_pos = c;
-	if (c == 0 && port->active) {
+	if (c == 0 && port->active && port->removing) {
 		spa_list_remove(&port->mix_link);
 		port->active = false;
 	}
@@ -933,7 +936,7 @@ static int impl_node_process(void *object)
 			if (size >= sizeof(float))
 				inport->history[0] = s[size/sizeof(float)-1];
 			inio->status = SPA_STATUS_NEED_DATA;
-		} else if (inio == NULL) {
+		} else if (inport->ramp_pos > 0) {
 			/* removed port, ramp down */
 			struct ramp_info *ri = &ramps[n_ramps++];
 			ri->port = inport;