From: Clemens Ladisch <clemens@ladisch.de>
Date: Tue, 11 Dec 2007 07:55:16 +0000 (+0100)
Subject: [ALSA] cmipci: document 'Modem' control version check
X-Git-Tag: v3.12-rc1~24018^2~211
X-Git-Url: http://review.tizen.org/git/?a=commitdiff_plain;h=25543fa785a32ce22e7374ba403eb6d38854d037;p=kernel%2Fkernel-generic.git

[ALSA] cmipci: document 'Modem' control version check

Add a comment that explains why the 'Modem' control doesn't work with
newer chips.

Signed-off-by: Clemens Ladisch <clemens@ladisch.de>
Signed-off-by: Jaroslav Kysela <perex@perex.cz>
---

diff --git a/sound/pci/cmipci.c b/sound/pci/cmipci.c
index 8cb3436..bc0a195 100644
--- a/sound/pci/cmipci.c
+++ b/sound/pci/cmipci.c
@@ -2733,6 +2733,10 @@ static int __devinit snd_cmipci_mixer_new(struct cmipci *cm, int pcm_spdif_devic
 	}
 
 	/* card switches */
+	/*
+	 * newer chips don't have the register bits to force modem link
+	 * detection; the bit that was FLINKON now mutes CH1
+	 */
 	if (cm->chip_version < 39) {
 		err = snd_ctl_add(cm->card,
 				  snd_ctl_new1(&snd_cmipci_modem_switch, cm));