ALSA: Warn when control names are truncated

This is likely to confuse user interfaces since the end of the control
name is interpreted (eg, "Volume", "Switch").

Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Signed-off-by: Takashi Iwai <tiwai@suse.de>

sound/core/control.c

@@ -225,8 +225,13 @@ struct snd_kcontrol *snd_ctl_new1(const struct snd_kcontrol_new *ncontrol,
 	kctl.id.iface = ncontrol->iface;
 	kctl.id.device = ncontrol->device;
 	kctl.id.subdevice = ncontrol->subdevice;
-	if (ncontrol->name)
+	if (ncontrol->name) {
 		strlcpy(kctl.id.name, ncontrol->name, sizeof(kctl.id.name));
+		if (strcmp(ncontrol->name, kctl.id.name) != 0)
+			snd_printk(KERN_WARNING
+				   "Control name '%s' truncated to '%s'\n",
+				   ncontrol->name, kctl.id.name);
+	}
 	kctl.id.index = ncontrol->index;
 	kctl.count = ncontrol->count ? ncontrol->count : 1;
 	access = ncontrol->access == 0 ? SNDRV_CTL_ELEM_ACCESS_READWRITE :