[alsa-devel] [PATCH]: sound/usb/mixer.c: Volume quirks compare empty string kctl->id.name.

[Christian Melki]

> > Hi,
> > 
> > Sorry to mail you directly. But I have tried to mail several times to 
> > the mailing list but I don't get through. Everything checks out fine, 
> > no html etc, other mailing lists work fine, but not alsa devel.
> > Anyway, could you please have a look at this?
> 
> Could you resend the patch but just add me, Clemens and Daniel to Cc, so that it reaches to main developers for usb-audio?  Even if we take your patch as is, it'd be needed to be applicable via git-am.
> 
> 
> thanks,
> 
> Takashi

Hi.

I noticied that volume quirks in usb-audio did not get applied.
This is because kctl->id.name gets built properly _after_ calling the quirk adjustments.
My solution is a bit ugly, but check_mapped_dB needs the adjustment before getting called.
I split the call over the switch. If someone feels like writing something cleaner, please feel free.
This works for me atleast.

Regards,
Christian Melki

Signed-off-by: Christian Melki <christian.melki at ericsson.se>
---

diff -urN linux-3.3.2.orig/sound/usb/mixer.c linux-3.3.2/sound/usb/mixer.c
--- linux-3.3.2.orig//sound/usb/mixer.c	2012-04-30 09:08:29.000000000 +0200
+++ linux-3.3.2/sound/usb/mixer.c	2012-04-30 09:46:28.000000000 +0200
@@ -1121,9 +1121,6 @@
 		len = snd_usb_copy_string_desc(state, nameid,
 				kctl->id.name, sizeof(kctl->id.name));
 
-	/* get min/max values */
-	get_min_max_with_quirks(cval, 0, kctl);
-
 	switch (control) {
 	case UAC_FU_MUTE:
 	case UAC_FU_VOLUME:
@@ -1155,6 +1152,7 @@
 		}
 		append_ctl_name(kctl, control == UAC_FU_MUTE ?
 				" Switch" : " Volume");
+		get_min_max_with_quirks(cval, 0, kctl);
 		if (control == UAC_FU_VOLUME) {
 			check_mapped_dB(map, cval);
 			if (cval->dBmin < cval->dBmax || !cval->initialized) {
@@ -1170,6 +1168,7 @@
 		if (! len)
 			strlcpy(kctl->id.name, audio_feature_info[control-1].name,
 				sizeof(kctl->id.name));
+		get_min_max_with_quirks(cval, 0, kctl);
 		break;
 	}