[3.16.y-ckt stable] Patch "ALSA: synth: Fix conflicting OSS device registration on AWE32" has been added to staging queue

[Luis Henriques]

This is a note to let you know that I have just added a patch titled

    ALSA: synth: Fix conflicting OSS device registration on AWE32

to the linux-3.16.y-queue branch of the 3.16.y-ckt extended stable tree 
which can be found at:

    http://kernel.ubuntu.com/git/ubuntu/linux.git/log/?h=linux-3.16.y-queue

This patch is scheduled to be released in version 3.16.7-ckt20.

If you, or anyone else, feels it should not be added to this tree, please 
reply to this email.

For more information about the 3.16.y-ckt tree, see
https://wiki.ubuntu.com/Kernel/Dev/ExtendedStable

Thanks.
-Luis

------

>From 6be8542eb3618692dfb607626ad55d12f87484b3 Mon Sep 17 00:00:00 2001
From: Takashi Iwai <tiwai at suse.de>
Date: Mon, 5 Oct 2015 16:55:09 +0200
Subject: ALSA: synth: Fix conflicting OSS device registration on AWE32

commit 225db5762dc1a35b26850477ffa06e5cd0097243 upstream.

When OSS emulation is loaded on ISA SB AWE32 chip, we get now kernel
warnings like:
  WARNING: CPU: 0 PID: 2791 at fs/sysfs/dir.c:31 sysfs_warn_dup+0x51/0x80()
  sysfs: cannot create duplicate filename '/devices/isa/sbawe.0/sound/card0/seq-oss-0-0'

It's because both emux synth and opl3 drivers try to register their
OSS device object with the same static index number 0.  This hasn't
been a big problem until the recent rewrite of device management code
(that exposes sysfs at the same time), but it's been an obvious bug.

This patch works around it just by using a different index number of
emux synth object.  There can be a more elegant way to fix, but it's
enough for now, as this code won't be touched so often, in anyway.

Reported-and-tested-by: Michael Shell <list1 at michaelshell.org>
Signed-off-by: Takashi Iwai <tiwai at suse.de>
Signed-off-by: Luis Henriques <luis.henriques at canonical.com>
---
 sound/synth/emux/emux_oss.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/sound/synth/emux/emux_oss.c b/sound/synth/emux/emux_oss.c
index daf61abc3670..646b66703bd8 100644
--- a/sound/synth/emux/emux_oss.c
+++ b/sound/synth/emux/emux_oss.c
@@ -69,7 +69,8 @@ snd_emux_init_seq_oss(struct snd_emux *emu)
 	struct snd_seq_oss_reg *arg;
 	struct snd_seq_device *dev;

-	if (snd_seq_device_new(emu->card, 0, SNDRV_SEQ_DEV_ID_OSS,
+	/* using device#1 here for avoiding conflicts with OPL3 */
+	if (snd_seq_device_new(emu->card, 1, SNDRV_SEQ_DEV_ID_OSS,
 			       sizeof(struct snd_seq_oss_reg), &dev) < 0)
 		return;