From 8426bb3aaf4ebbe17483a159edbc3c7dcf13e781 Mon Sep 17 00:00:00 2001
From: Robin Gareus <robin@gareus.org>
Date: Fri, 22 Jan 2021 16:06:18 +0100
Subject: [PATCH] ALSA: explicitly list millisecond buffer-sizes

---
 libs/backends/alsa/alsa_audiobackend.cc | 15 +++++++++++++++
 1 file changed, 15 insertions(+)

diff --git a/libs/backends/alsa/alsa_audiobackend.cc b/libs/backends/alsa/alsa_audiobackend.cc
index e0b25e114d..adb2990e46 100644
--- a/libs/backends/alsa/alsa_audiobackend.cc
+++ b/libs/backends/alsa/alsa_audiobackend.cc
@@ -236,6 +236,21 @@ AlsaAudioBackend::available_buffer_sizes (const std::string& device) const
 			bs.push_back (avail_sizes[i]);
 		}
 	}
+
+	if (!nfo) {
+		return bs;
+	}
+
+	static const unsigned long try_msec [] = { 2, 4, 5, 6, 8, 10, 15, 20, 25, 40};
+
+	for (size_t i = 0 ; i < sizeof(try_msec) / sizeof(unsigned long); ++i) {
+		unsigned int msbs = _samplerate * try_msec[i] / 1000;
+		if (msbs >= nfo->min_size && msbs <= nfo->max_size) {
+			bs.push_back (msbs);
+		}
+	}
+
+	std::sort (bs.begin (), bs.end ());
 	return bs;
 }