[PATCH 5.12 659/700] ALSA: firewire-lib: Fix amdtp_domain_start() when no AMDTP_OUT_STREAM stream is found

[Greg Kroah-Hartman]

From: Christophe JAILLET <christophe.jaillet@xxxxxxxxxx>

[ Upstream commit 0cbbeaf370221fc469c95945dd3c1198865c5fe4 ]

The intent here is to return an error code if we don't find what we are
looking for in the 'list_for_each_entry()' loop.

's' is not NULL if the list is empty or if we scan the complete list.
Introduce a new 'found' variable to handle such cases.

Fixes: 60dd49298ec5 ("ALSA: firewire-lib: handle several AMDTP streams in callback handler of IRQ target")
Signed-off-by: Christophe JAILLET <christophe.jaillet@xxxxxxxxxx>
Acked-by: Takashi Sakamoto <o-takashi@xxxxxxxxxxxxx>
Link: https://lore.kernel.org/r/9c9a53a4905984a570ba5672cbab84f2027dedc1.1624560484.git.christophe.jaillet@xxxxxxxxxx
Signed-off-by: Takashi Iwai <tiwai@xxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
 sound/firewire/amdtp-stream.c | 7 +++++--
 1 file changed, 5 insertions(+), 2 deletions(-)

diff --git a/sound/firewire/amdtp-stream.c b/sound/firewire/amdtp-stream.c
index 5805c5de39fb..7a282d8e7148 100644
--- a/sound/firewire/amdtp-stream.c
+++ b/sound/firewire/amdtp-stream.c
@@ -1404,14 +1404,17 @@ int amdtp_domain_start(struct amdtp_domain *d, unsigned int ir_delay_cycle)
 	unsigned int queue_size;
 	struct amdtp_stream *s;
 	int cycle;
+	bool found = false;
 	int err;
 
 	// Select an IT context as IRQ target.
 	list_for_each_entry(s, &d->streams, list) {
-		if (s->direction == AMDTP_OUT_STREAM)
+		if (s->direction == AMDTP_OUT_STREAM) {
+			found = true;
 			break;
+		}
 	}
-	if (!s)
+	if (!found)
 		return -ENXIO;
 	d->irq_target = s;
 
-- 
2.30.2