[ALSA] powermac - Add AUTO_DRC config

PPC,PPC Tumbler driver
Added AUTO_DRC kernel config to enable/disable the auto-DRC-toggle
feature on tumbler/snapper.

Signed-off-by: Takashi Iwai <tiwai@suse.de>

sound/ppc/Kconfig

@@ -20,5 +20,17 @@ config SND_POWERMAC
 	  To compile this driver as a module, choose M here: the module
 	  will be called snd-powermac.
 
-endmenu
+config SND_POWERMAC_AUTO_DRC
+	bool "Toggle DRC automatically at headphone/line plug-in"
+	depends on SND_POWERMAC
+	default y
+	help
+	  Say Y here to enable the automatic toggle of DRC (dynamic
+	  range compression) on Tumbler/Snapper.
+	  If this feature is enabled, DRC is turned off when the
+	  headphone/line jack is plugged, and turned on when unplugged.
 
+	  Note that you can turn on/off DRC manually even without this
+	  option.
+
+endmenu

sound/ppc/tumbler.c

@@ -948,7 +948,6 @@ static void device_change_handler(void *self)
 			msleep(10);
 		check_mute(chip, &mix->amp_mute, 1, mix->auto_mute_notify,
 			   chip->speaker_sw_ctl);
-		mix->drc_enable = 0;
 	} else {
 		/* unmute speaker, mute others */
 		check_mute(chip, &mix->amp_mute, 0, mix->auto_mute_notify,
@@ -960,20 +959,21 @@ static void device_change_handler(void *self)
 		if (mix->line_mute.addr != 0)
 			check_mute(chip, &mix->line_mute, 1, mix->auto_mute_notify,
 				   chip->lineout_sw_ctl);
-		mix->drc_enable = 1;
 	}
-	if (mix->auto_mute_notify) {
+	if (mix->auto_mute_notify)
 		snd_ctl_notify(chip->card, SNDRV_CTL_EVENT_MASK_VALUE,
 				       &chip->hp_detect_ctl->id);
+
+#ifdef CONFIG_SND_POWERMAC_AUTO_DRC
+	mix->drc_enable = ! (headphone || lineout);
+	if (mix->auto_mute_notify)
 		snd_ctl_notify(chip->card, SNDRV_CTL_EVENT_MASK_VALUE,
 			       &chip->drc_sw_ctl->id);
-	}
-
-	/* first set the DRC so the speaker do not explode -ReneR */
 	if (chip->model == PMAC_TUMBLER)
 		tumbler_set_drc(mix);
 	else
 		snapper_set_drc(mix);
+#endif
 
 	/* reset the master volume so the correct amplification is applied */
 	tumbler_set_master_volume(mix);
@@ -1370,6 +1370,17 @@ int __init snd_pmac_tumbler_init(pmac_t *chip)
 	if ((err = snd_ctl_add(chip->card, chip->drc_sw_ctl)) < 0)
 		return err;
 
+	/* set initial DRC range to 60% */
+	if (chip->model == PMAC_TUMBLER)
+		mix->drc_range = (TAS3001_DRC_MAX * 6) / 10;
+	else
+		mix->drc_range = (TAS3004_DRC_MAX * 6) / 10;
+	mix->drc_enable = 1; /* will be changed later if AUTO_DRC is set */
+	if (chip->model == PMAC_TUMBLER)
+		tumbler_set_drc(mix);
+	else
+		snapper_set_drc(mix);
+
 #ifdef CONFIG_PM
 	chip->suspend = tumbler_suspend;
 	chip->resume = tumbler_resume;