From 9b4702b06c0e25abc612e6f02f3e25a51c684a01 Mon Sep 17 00:00:00 2001
From: Takashi Sakamoto <o-takashi@sakamocchi.jp>
Date: Sun, 4 Aug 2019 15:21:23 +0900
Subject: [PATCH] ALSA: firewire-lib: add a kernel API to start AMDTP streams in AMDTP domain
Git-commit: 9b4702b06c0e25abc612e6f02f3e25a51c684a01
Patch-mainline: v5.4-rc1
References: jsc#SLE-16518

This commit adds a kernel API to start a couple of isochronous contexts
for some AMDTP streams.

Signed-off-by: Takashi Sakamoto <o-takashi@sakamocchi.jp>
Signed-off-by: Takashi Iwai <tiwai@suse.de>

---
 sound/firewire/amdtp-stream.c | 24 ++++++++++++++++++++++++
 sound/firewire/amdtp-stream.h |  1 +
 2 files changed, 25 insertions(+)

diff --git a/sound/firewire/amdtp-stream.c b/sound/firewire/amdtp-stream.c
index fa7989ee4769..158d210caea7 100644
--- a/sound/firewire/amdtp-stream.c
+++ b/sound/firewire/amdtp-stream.c
@@ -1185,6 +1185,30 @@ int amdtp_domain_add_stream(struct amdtp_domain *d, struct amdtp_stream *s,
 }
 EXPORT_SYMBOL_GPL(amdtp_domain_add_stream);
 
+/**
+ * amdtp_domain_start - start sending packets for isoc context in the domain.
+ * @d: the AMDTP domain.
+ */
+int amdtp_domain_start(struct amdtp_domain *d)
+{
+	struct amdtp_stream *s;
+	int err = 0;
+
+	list_for_each_entry(s, &d->streams, list) {
+		err = amdtp_stream_start(s, s->channel, s->speed);
+		if (err < 0)
+			break;
+	}
+
+	if (err < 0) {
+		list_for_each_entry(s, &d->streams, list)
+			amdtp_stream_stop(s);
+	}
+
+	return err;
+}
+EXPORT_SYMBOL_GPL(amdtp_domain_start);
+
 /**
  * amdtp_domain_stop - stop sending packets for isoc context in the same domain.
  * @d: the AMDTP domain to which the isoc contexts belong.
diff --git a/sound/firewire/amdtp-stream.h b/sound/firewire/amdtp-stream.h
index 4b102fd7529d..15d471660a43 100644
--- a/sound/firewire/amdtp-stream.h
+++ b/sound/firewire/amdtp-stream.h
@@ -282,6 +282,7 @@ void amdtp_domain_destroy(struct amdtp_domain *d);
 int amdtp_domain_add_stream(struct amdtp_domain *d, struct amdtp_stream *s,
 			    int channel, int speed);
 
+int amdtp_domain_start(struct amdtp_domain *d);
 void amdtp_domain_stop(struct amdtp_domain *d);
 
 #endif
-- 
2.16.4