Merge commit 'linus/master' into HEAD

Conflicts:
	MAINTAINERS

Signed-off-by: Vegard Nossum <vegard.nossum@gmail.com>

1 files changed, 285 insertions, 142 deletions

diff --git a/sound/soc/soc-dapm.c b/sound/soc/soc-dapm.c
index 735903a74675..21c69074aa17 100644
--- a/sound/soc/soc-dapm.c
+++ b/sound/soc/soc-dapm.c
@@ -12,7 +12,7 @@
  *  Features:
  *    o Changes power status of internal codec blocks depending on the
  *      dynamic configuration of codec internal audio paths and active
- *      DAC's/ADC's.
+ *      DACs/ADCs.
  *    o Platform power domain - can support external components i.e. amps and
  *      mic/meadphone insertion events.
  *    o Automatic Mic Bias support
@@ -52,23 +52,21 @@
 
 /* dapm power sequences - make this per codec in the future */
 static int dapm_up_seq[] = {
-	snd_soc_dapm_pre, snd_soc_dapm_micbias, snd_soc_dapm_mic,
-	snd_soc_dapm_mux, snd_soc_dapm_value_mux, snd_soc_dapm_dac,
-	snd_soc_dapm_mixer, snd_soc_dapm_mixer_named_ctl, snd_soc_dapm_pga,
-	snd_soc_dapm_adc, snd_soc_dapm_hp, snd_soc_dapm_spk, snd_soc_dapm_post
+	snd_soc_dapm_pre, snd_soc_dapm_supply, snd_soc_dapm_micbias,
+	snd_soc_dapm_mic, snd_soc_dapm_mux, snd_soc_dapm_value_mux,
+	snd_soc_dapm_dac, snd_soc_dapm_mixer, snd_soc_dapm_mixer_named_ctl,
+	snd_soc_dapm_pga, snd_soc_dapm_adc, snd_soc_dapm_hp, snd_soc_dapm_spk,
+	snd_soc_dapm_post
 };
 
 static int dapm_down_seq[] = {
 	snd_soc_dapm_pre, snd_soc_dapm_adc, snd_soc_dapm_hp, snd_soc_dapm_spk,
 	snd_soc_dapm_pga, snd_soc_dapm_mixer_named_ctl, snd_soc_dapm_mixer,
 	snd_soc_dapm_dac, snd_soc_dapm_mic, snd_soc_dapm_micbias,
-	snd_soc_dapm_mux, snd_soc_dapm_value_mux, snd_soc_dapm_post
+	snd_soc_dapm_mux, snd_soc_dapm_value_mux, snd_soc_dapm_supply,
+	snd_soc_dapm_post
 };
 
-static int dapm_status = 1;
-module_param(dapm_status, int, 0);
-MODULE_PARM_DESC(dapm_status, "enable DPM sysfs entries");
-
 static void pop_wait(u32 pop_time)
 {
 	if (pop_time)
@@ -96,6 +94,48 @@ static inline struct snd_soc_dapm_widget *dapm_cnew_widget(
 	return kmemdup(_widget, sizeof(*_widget), GFP_KERNEL);
 }
 
+/**
+ * snd_soc_dapm_set_bias_level - set the bias level for the system
+ * @socdev: audio device
+ * @level: level to configure
+ *
+ * Configure the bias (power) levels for the SoC audio device.
+ *
+ * Returns 0 for success else error.
+ */
+static int snd_soc_dapm_set_bias_level(struct snd_soc_device *socdev,
+				       enum snd_soc_bias_level level)
+{
+	struct snd_soc_card *card = socdev->card;
+	struct snd_soc_codec *codec = socdev->card->codec;
+	int ret = 0;
+
+	switch (level) {
+	case SND_SOC_BIAS_ON:
+		dev_dbg(socdev->dev, "Setting full bias\n");
+		break;
+	case SND_SOC_BIAS_PREPARE:
+		dev_dbg(socdev->dev, "Setting bias prepare\n");
+		break;
+	case SND_SOC_BIAS_STANDBY:
+		dev_dbg(socdev->dev, "Setting standby bias\n");
+		break;
+	case SND_SOC_BIAS_OFF:
+		dev_dbg(socdev->dev, "Setting bias off\n");
+		break;
+	default:
+		dev_err(socdev->dev, "Setting invalid bias %d\n", level);
+		return -EINVAL;
+	}
+
+	if (card->set_bias_level)
+		ret = card->set_bias_level(card, level);
+	if (ret == 0 && codec->set_bias_level)
+		ret = codec->set_bias_level(codec, level);
+
+	return ret;
+}
+
 /* set up initial codec paths */
 static void dapm_set_path_status(struct snd_soc_dapm_widget *w,
 	struct snd_soc_dapm_path *p, int i)
@@ -165,6 +205,7 @@ static void dapm_set_path_status(struct snd_soc_dapm_widget *w,
 	case snd_soc_dapm_dac:
 	case snd_soc_dapm_micbias:
 	case snd_soc_dapm_vmid:
+	case snd_soc_dapm_supply:
 		p->connect = 1;
 	break;
 	/* does effect routing - dynamically connected */
@@ -179,7 +220,7 @@ static void dapm_set_path_status(struct snd_soc_dapm_widget *w,
 	}
 }
 
-/* connect mux widget to it's interconnecting audio paths */
+/* connect mux widget to its interconnecting audio paths */
 static int dapm_connect_mux(struct snd_soc_codec *codec,
 	struct snd_soc_dapm_widget *src, struct snd_soc_dapm_widget *dest,
 	struct snd_soc_dapm_path *path, const char *control_name,
@@ -202,7 +243,7 @@ static int dapm_connect_mux(struct snd_soc_codec *codec,
 	return -ENODEV;
 }
 
-/* connect mixer widget to it's interconnecting audio paths */
+/* connect mixer widget to its interconnecting audio paths */
 static int dapm_connect_mixer(struct snd_soc_codec *codec,
 	struct snd_soc_dapm_widget *src, struct snd_soc_dapm_widget *dest,
 	struct snd_soc_dapm_path *path, const char *control_name)
@@ -357,8 +398,9 @@ static int dapm_new_mixer(struct snd_soc_codec *codec,
 				path->long_name);
 			ret = snd_ctl_add(codec->card, path->kcontrol);
 			if (ret < 0) {
-				printk(KERN_ERR "asoc: failed to add dapm kcontrol %s\n",
-						path->long_name);
+				printk(KERN_ERR "asoc: failed to add dapm kcontrol %s: %d\n",
+				       path->long_name,
+				       ret);
 				kfree(path->long_name);
 				path->long_name = NULL;
 				return ret;
@@ -434,6 +476,9 @@ static int is_connected_output_ep(struct snd_soc_dapm_widget *widget)
 	struct snd_soc_dapm_path *path;
 	int con = 0;
 
+	if (widget->id == snd_soc_dapm_supply)
+		return 0;
+
 	if (widget->id == snd_soc_dapm_adc && widget->active)
 		return 1;
 
@@ -470,6 +515,9 @@ static int is_connected_input_ep(struct snd_soc_dapm_widget *widget)
 	struct snd_soc_dapm_path *path;
 	int con = 0;
 
+	if (widget->id == snd_soc_dapm_supply)
+		return 0;
+
 	/* active stream ? */
 	if (widget->id == snd_soc_dapm_dac && widget->active)
 		return 1;
@@ -521,84 +569,12 @@ int dapm_reg_event(struct snd_soc_dapm_widget *w,
 }
 EXPORT_SYMBOL_GPL(dapm_reg_event);
 
-/*
- * Scan a single DAPM widget for a complete audio path and update the
- * power status appropriately.
+/* Standard power change method, used to apply power changes to most
+ * widgets.
  */
-static int dapm_power_widget(struct snd_soc_codec *codec, int event,
-			     struct snd_soc_dapm_widget *w)
+static int dapm_generic_apply_power(struct snd_soc_dapm_widget *w)
 {
-	int in, out, power_change, power, ret;
-
-	/* vmid - no action */
-	if (w->id == snd_soc_dapm_vmid)
-		return 0;
-
-	/* active ADC */
-	if (w->id == snd_soc_dapm_adc && w->active) {
-		in = is_connected_input_ep(w);
-		dapm_clear_walk(w->codec);
-		w->power = (in != 0) ? 1 : 0;
-		dapm_update_bits(w);
-		return 0;
-	}
-
-	/* active DAC */
-	if (w->id == snd_soc_dapm_dac && w->active) {
-		out = is_connected_output_ep(w);
-		dapm_clear_walk(w->codec);
-		w->power = (out != 0) ? 1 : 0;
-		dapm_update_bits(w);
-		return 0;
-	}
-
-	/* pre and post event widgets */
-	if (w->id == snd_soc_dapm_pre) {
-		if (!w->event)
-			return 0;
-
-		if (event == SND_SOC_DAPM_STREAM_START) {
-			ret = w->event(w,
-				       NULL, SND_SOC_DAPM_PRE_PMU);
-			if (ret < 0)
-				return ret;
-		} else if (event == SND_SOC_DAPM_STREAM_STOP) {
-			ret = w->event(w,
-				       NULL, SND_SOC_DAPM_PRE_PMD);
-			if (ret < 0)
-				return ret;
-		}
-		return 0;
-	}
-	if (w->id == snd_soc_dapm_post) {
-		if (!w->event)
-			return 0;
-
-		if (event == SND_SOC_DAPM_STREAM_START) {
-			ret = w->event(w,
-				       NULL, SND_SOC_DAPM_POST_PMU);
-			if (ret < 0)
-				return ret;
-		} else if (event == SND_SOC_DAPM_STREAM_STOP) {
-			ret = w->event(w,
-				       NULL, SND_SOC_DAPM_POST_PMD);
-			if (ret < 0)
-				return ret;
-		}
-		return 0;
-	}
-
-	/* all other widgets */
-	in = is_connected_input_ep(w);
-	dapm_clear_walk(w->codec);
-	out = is_connected_output_ep(w);
-	dapm_clear_walk(w->codec);
-	power = (out != 0 && in != 0) ? 1 : 0;
-	power_change = (w->power == power) ? 0 : 1;
-	w->power = power;
-
-	if (!power_change)
-		return 0;
+	int ret;
 
 	/* call any power change event handlers */
 	if (w->event)
@@ -607,7 +583,7 @@ static int dapm_power_widget(struct snd_soc_codec *codec, int event,
 			 w->name, w->event_flags);
 
 	/* power up pre event */
-	if (power && w->event &&
+	if (w->power && w->event &&
 	    (w->event_flags & SND_SOC_DAPM_PRE_PMU)) {
 		ret = w->event(w, NULL, SND_SOC_DAPM_PRE_PMU);
 		if (ret < 0)
@@ -615,7 +591,7 @@ static int dapm_power_widget(struct snd_soc_codec *codec, int event,
 	}
 
 	/* power down pre event */
-	if (!power && w->event &&
+	if (!w->power && w->event &&
 	    (w->event_flags & SND_SOC_DAPM_PRE_PMD)) {
 		ret = w->event(w, NULL, SND_SOC_DAPM_PRE_PMD);
 		if (ret < 0)
@@ -623,17 +599,17 @@ static int dapm_power_widget(struct snd_soc_codec *codec, int event,
 	}
 
 	/* Lower PGA volume to reduce pops */
-	if (w->id == snd_soc_dapm_pga && !power)
-		dapm_set_pga(w, power);
+	if (w->id == snd_soc_dapm_pga && !w->power)
+		dapm_set_pga(w, w->power);
 
 	dapm_update_bits(w);
 
 	/* Raise PGA volume to reduce pops */
-	if (w->id == snd_soc_dapm_pga && power)
-		dapm_set_pga(w, power);
+	if (w->id == snd_soc_dapm_pga && w->power)
+		dapm_set_pga(w, w->power);
 
 	/* power up post event */
-	if (power && w->event &&
+	if (w->power && w->event &&
 	    (w->event_flags & SND_SOC_DAPM_POST_PMU)) {
 		ret = w->event(w,
 			       NULL, SND_SOC_DAPM_POST_PMU);
@@ -642,7 +618,7 @@ static int dapm_power_widget(struct snd_soc_codec *codec, int event,
 	}
 
 	/* power down post event */
-	if (!power && w->event &&
+	if (!w->power && w->event &&
 	    (w->event_flags & SND_SOC_DAPM_POST_PMD)) {
 		ret = w->event(w, NULL, SND_SOC_DAPM_POST_PMD);
 		if (ret < 0)
@@ -652,6 +628,116 @@ static int dapm_power_widget(struct snd_soc_codec *codec, int event,
 	return 0;
 }
 
+/* Generic check to see if a widget should be powered.
+ */
+static int dapm_generic_check_power(struct snd_soc_dapm_widget *w)
+{
+	int in, out;
+
+	in = is_connected_input_ep(w);
+	dapm_clear_walk(w->codec);
+	out = is_connected_output_ep(w);
+	dapm_clear_walk(w->codec);
+	return out != 0 && in != 0;
+}
+
+/* Check to see if an ADC has power */
+static int dapm_adc_check_power(struct snd_soc_dapm_widget *w)
+{
+	int in;
+
+	if (w->active) {
+		in = is_connected_input_ep(w);
+		dapm_clear_walk(w->codec);
+		return in != 0;
+	} else {
+		return dapm_generic_check_power(w);
+	}
+}
+
+/* Check to see if a DAC has power */
+static int dapm_dac_check_power(struct snd_soc_dapm_widget *w)
+{
+	int out;
+
+	if (w->active) {
+		out = is_connected_output_ep(w);
+		dapm_clear_walk(w->codec);
+		return out != 0;
+	} else {
+		return dapm_generic_check_power(w);
+	}
+}
+
+/* Check to see if a power supply is needed */
+static int dapm_supply_check_power(struct snd_soc_dapm_widget *w)
+{
+	struct snd_soc_dapm_path *path;
+	int power = 0;
+
+	/* Check if one of our outputs is connected */
+	list_for_each_entry(path, &w->sinks, list_source) {
+		if (path->sink && path->sink->power_check &&
+		    path->sink->power_check(path->sink)) {
+			power = 1;
+			break;
+		}
+	}
+
+	dapm_clear_walk(w->codec);
+
+	return power;
+}
+
+/*
+ * Scan a single DAPM widget for a complete audio path and update the
+ * power status appropriately.
+ */
+static int dapm_power_widget(struct snd_soc_codec *codec, int event,
+			     struct snd_soc_dapm_widget *w)
+{
+	int ret;
+
+	switch (w->id) {
+	case snd_soc_dapm_pre:
+		if (!w->event)
+			return 0;
+
+		if (event == SND_SOC_DAPM_STREAM_START) {
+			ret = w->event(w,
+				       NULL, SND_SOC_DAPM_PRE_PMU);
+			if (ret < 0)
+				return ret;
+		} else if (event == SND_SOC_DAPM_STREAM_STOP) {
+			ret = w->event(w,
+				       NULL, SND_SOC_DAPM_PRE_PMD);
+			if (ret < 0)
+				return ret;
+		}
+		return 0;
+
+	case snd_soc_dapm_post:
+		if (!w->event)
+			return 0;
+
+		if (event == SND_SOC_DAPM_STREAM_START) {
+			ret = w->event(w,
+				       NULL, SND_SOC_DAPM_POST_PMU);
+			if (ret < 0)
+				return ret;
+		} else if (event == SND_SOC_DAPM_STREAM_STOP) {
+			ret = w->event(w,
+				       NULL, SND_SOC_DAPM_POST_PMD);
+			if (ret < 0)
+				return ret;
+		}
+		return 0;
+
+	default:
+		return dapm_generic_apply_power(w);
+	}
+}
+
 /*
  * Scan each dapm widget for complete audio path.
  * A complete path is a route that has valid endpoints i.e.:-
@@ -663,31 +749,102 @@ static int dapm_power_widget(struct snd_soc_codec *codec, int event,
  */
 static int dapm_power_widgets(struct snd_soc_codec *codec, int event)
 {
+	struct snd_soc_device *socdev = codec->socdev;
 	struct snd_soc_dapm_widget *w;
-	int i, c = 1, *seq = NULL, ret = 0;
-
-	/* do we have a sequenced stream event */
-	if (event == SND_SOC_DAPM_STREAM_START) {
-		c = ARRAY_SIZE(dapm_up_seq);
-		seq = dapm_up_seq;
-	} else if (event == SND_SOC_DAPM_STREAM_STOP) {
-		c = ARRAY_SIZE(dapm_down_seq);
-		seq = dapm_down_seq;
+	int ret = 0;
+	int i, power;
+	int sys_power = 0;
+
+	INIT_LIST_HEAD(&codec->up_list);
+	INIT_LIST_HEAD(&codec->down_list);
+
+	/* Check which widgets we need to power and store them in
+	 * lists indicating if they should be powered up or down.
+	 */
+	list_for_each_entry(w, &codec->dapm_widgets, list) {
+		switch (w->id) {
+		case snd_soc_dapm_pre:
+			list_add_tail(&codec->down_list, &w->power_list);
+			break;
+		case snd_soc_dapm_post:
+			list_add_tail(&codec->up_list, &w->power_list);
+			break;
+
+		default:
+			if (!w->power_check)
+				continue;
+
+			power = w->power_check(w);
+			if (power)
+				sys_power = 1;
+
+			if (w->power == power)
+				continue;
+
+			if (power)
+				list_add_tail(&w->power_list, &codec->up_list);
+			else
+				list_add_tail(&w->power_list,
+					      &codec->down_list);
+
+			w->power = power;
+			break;
+		}
 	}
 
-	for (i = 0; i < c; i++) {
-		list_for_each_entry(w, &codec->dapm_widgets, list) {
+	/* If we're changing to all on or all off then prepare */
+	if ((sys_power && codec->bias_level == SND_SOC_BIAS_STANDBY) ||
+	    (!sys_power && codec->bias_level == SND_SOC_BIAS_ON)) {
+		ret = snd_soc_dapm_set_bias_level(socdev,
+						  SND_SOC_BIAS_PREPARE);
+		if (ret != 0)
+			pr_err("Failed to prepare bias: %d\n", ret);
+	}
 
+	/* Power down widgets first; try to avoid amplifying pops. */
+	for (i = 0; i < ARRAY_SIZE(dapm_down_seq); i++) {
+		list_for_each_entry(w, &codec->down_list, power_list) {
 			/* is widget in stream order */
-			if (seq && seq[i] && w->id != seq[i])
+			if (w->id != dapm_down_seq[i])
 				continue;
 
 			ret = dapm_power_widget(codec, event, w);
 			if (ret != 0)
-				return ret;
+				pr_err("Failed to power down %s: %d\n",
+				       w->name, ret);
 		}
 	}
 
+	/* Now power up. */
+	for (i = 0; i < ARRAY_SIZE(dapm_up_seq); i++) {
+		list_for_each_entry(w, &codec->up_list, power_list) {
+			/* is widget in stream order */
+			if (w->id != dapm_up_seq[i])
+				continue;
+
+			ret = dapm_power_widget(codec, event, w);
+			if (ret != 0)
+				pr_err("Failed to power up %s: %d\n",
+				       w->name, ret);
+		}
+	}
+
+	/* If we just powered the last thing off drop to standby bias */
+	if (codec->bias_level == SND_SOC_BIAS_PREPARE && !sys_power) {
+		ret = snd_soc_dapm_set_bias_level(socdev,
+						  SND_SOC_BIAS_STANDBY);
+		if (ret != 0)
+			pr_err("Failed to apply standby bias: %d\n", ret);
+	}
+
+	/* If we just powered up then move to active bias */
+	if (codec->bias_level == SND_SOC_BIAS_PREPARE && sys_power) {
+		ret = snd_soc_dapm_set_bias_level(socdev,
+						  SND_SOC_BIAS_ON);
+		if (ret != 0)
+			pr_err("Failed to apply active bias: %d\n", ret);
+	}
+
 	return 0;
 }
 
@@ -723,6 +880,7 @@ static void dbg_dump_dapm(struct snd_soc_codec* codec, const char *action)
 		case snd_soc_dapm_pga:
 		case snd_soc_dapm_mixer:
 		case snd_soc_dapm_mixer_named_ctl:
+		case snd_soc_dapm_supply:
 			if (w->name) {
 				in = is_connected_input_ep(w);
 				dapm_clear_walk(w->codec);
@@ -851,6 +1009,7 @@ static ssize_t dapm_widget_show(struct device *dev,
 		case snd_soc_dapm_pga:
 		case snd_soc_dapm_mixer:
 		case snd_soc_dapm_mixer_named_ctl:
+		case snd_soc_dapm_supply:
 			if (w->name)
 				count += sprintf(buf + count, "%s: %s\n",
 					w->name, w->power ? "On":"Off");
@@ -883,16 +1042,12 @@ static DEVICE_ATTR(dapm_widget, 0444, dapm_widget_show, NULL);
 
 int snd_soc_dapm_sys_add(struct device *dev)
 {
-	if (!dapm_status)
-		return 0;
 	return device_create_file(dev, &dev_attr_dapm_widget);
 }
 
 static void snd_soc_dapm_sys_remove(struct device *dev)
 {
-	if (dapm_status) {
-		device_remove_file(dev, &dev_attr_dapm_widget);
-	}
+	device_remove_file(dev, &dev_attr_dapm_widget);
 }
 
 /* free all dapm widgets and resources */
@@ -1015,6 +1170,7 @@ static int snd_soc_dapm_add_route(struct snd_soc_codec *codec,
 	case snd_soc_dapm_vmid:
 	case snd_soc_dapm_pre:
 	case snd_soc_dapm_post:
+	case snd_soc_dapm_supply:
 		list_add(&path->list, &codec->dapm_paths);
 		list_add(&path->list_sink, &wsink->sources);
 		list_add(&path->list_source, &wsource->sinks);
@@ -1108,15 +1264,22 @@ int snd_soc_dapm_new_widgets(struct snd_soc_codec *codec)
 		case snd_soc_dapm_switch:
 		case snd_soc_dapm_mixer:
 		case snd_soc_dapm_mixer_named_ctl:
+			w->power_check = dapm_generic_check_power;
 			dapm_new_mixer(codec, w);
 			break;
 		case snd_soc_dapm_mux:
 		case snd_soc_dapm_value_mux:
+			w->power_check = dapm_generic_check_power;
 			dapm_new_mux(codec, w);
 			break;
 		case snd_soc_dapm_adc:
+			w->power_check = dapm_adc_check_power;
+			break;
 		case snd_soc_dapm_dac:
+			w->power_check = dapm_dac_check_power;
+			break;
 		case snd_soc_dapm_pga:
+			w->power_check = dapm_generic_check_power;
 			dapm_new_pga(codec, w);
 			break;
 		case snd_soc_dapm_input:
@@ -1126,6 +1289,10 @@ int snd_soc_dapm_new_widgets(struct snd_soc_codec *codec)
 		case snd_soc_dapm_hp:
 		case snd_soc_dapm_mic:
 		case snd_soc_dapm_line:
+			w->power_check = dapm_generic_check_power;
+			break;
+		case snd_soc_dapm_supply:
+			w->power_check = dapm_supply_check_power;
 		case snd_soc_dapm_vmid:
 		case snd_soc_dapm_pre:
 		case snd_soc_dapm_post:
@@ -1626,35 +1793,11 @@ int snd_soc_dapm_stream_event(struct snd_soc_codec *codec,
 EXPORT_SYMBOL_GPL(snd_soc_dapm_stream_event);
 
 /**
- * snd_soc_dapm_set_bias_level - set the bias level for the system
- * @socdev: audio device
- * @level: level to configure
- *
- * Configure the bias (power) levels for the SoC audio device.
- *
- * Returns 0 for success else error.
- */
-int snd_soc_dapm_set_bias_level(struct snd_soc_device *socdev,
-				enum snd_soc_bias_level level)
-{
-	struct snd_soc_card *card = socdev->card;
-	struct snd_soc_codec *codec = socdev->card->codec;
-	int ret = 0;
-
-	if (card->set_bias_level)
-		ret = card->set_bias_level(card, level);
-	if (ret == 0 && codec->set_bias_level)
-		ret = codec->set_bias_level(codec, level);
-
-	return ret;
-}
-
-/**
  * snd_soc_dapm_enable_pin - enable pin.
  * @codec: SoC codec
  * @pin: pin name
  *
- * Enables input/output pin and it's parents or children widgets iff there is
+ * Enables input/output pin and its parents or children widgets iff there is
  * a valid audio route and active audio stream.
  * NOTE: snd_soc_dapm_sync() needs to be called after this for DAPM to
  * do any widget power switching.
@@ -1670,7 +1813,7 @@ EXPORT_SYMBOL_GPL(snd_soc_dapm_enable_pin);
  * @codec: SoC codec
  * @pin: pin name
  *
- * Disables input/output pin and it's parents or children widgets.
+ * Disables input/output pin and its parents or children widgets.
  * NOTE: snd_soc_dapm_sync() needs to be called after this for DAPM to
  * do any widget power switching.
  */