/*
   * soc-jack.c  --  ALSA SoC jack handling
   *
   * Copyright 2008 Wolfson Microelectronics PLC.
   *
   * Author: Mark Brown <broonie@opensource.wolfsonmicro.com>
   *
   *  This program is free software; you can redistribute  it and/or modify it
   *  under  the terms of  the GNU General  Public License as published by the
   *  Free Software Foundation;  either version 2 of the  License, or (at your
   *  option) any later version.
   */
  
  #include <sound/jack.h>
  #include <sound/soc.h>

  #include <linux/gpio.h>
  #include <linux/interrupt.h>
  #include <linux/workqueue.h>
  #include <linux/delay.h>

  #include <linux/export.h>

  #include <trace/events/asoc.h>

  
  /**
   * snd_soc_jack_new - Create a new jack
   * @card:  ASoC card
   * @id:    an identifying string for this jack
   * @type:  a bitmask of enum snd_jack_type values that can be detected by
   *         this jack
   * @jack:  structure to use for the jack
   *
   * Creates a new jack object.
   *
   * Returns zero if successful, or a negative error code on failure.
   * On success jack will be initialised.
   */

  int snd_soc_jack_new(struct snd_soc_codec *codec, const char *id, int type,

  		     struct snd_soc_jack *jack)
  {

  	jack->codec = codec;

  	INIT_LIST_HEAD(&jack->pins);

  	INIT_LIST_HEAD(&jack->jack_zones);

  	BLOCKING_INIT_NOTIFIER_HEAD(&jack->notifier);

  	return snd_jack_new(codec->card->snd_card, id, type, &jack->jack);

  }
  EXPORT_SYMBOL_GPL(snd_soc_jack_new);
  
  /**
   * snd_soc_jack_report - Report the current status for a jack
   *
   * @jack:   the jack
   * @status: a bitmask of enum snd_jack_type values that are currently detected.
   * @mask:   a bitmask of enum snd_jack_type values that being reported.
   *
   * If configured using snd_soc_jack_add_pins() then the associated
   * DAPM pins will be enabled or disabled as appropriate and DAPM
   * synchronised.
   *
   * Note: This function uses mutexes and should be called from a
   * context which can sleep (such as a workqueue).
   */
  void snd_soc_jack_report(struct snd_soc_jack *jack, int status, int mask)
  {

  	struct snd_soc_codec *codec;

  	struct snd_soc_dapm_context *dapm;

  	struct snd_soc_jack_pin *pin;
  	int enable;
  	int oldstatus;

  	trace_snd_soc_jack_report(jack, mask, status);

  	if (!jack)

  		return;

  	codec = jack->codec;

  	dapm =  &codec->dapm;

  
  	mutex_lock(&codec->mutex);
  
  	oldstatus = jack->status;
  
  	jack->status &= ~mask;

  	jack->status |= status & mask;

  	/* The DAPM sync is expensive enough to be worth skipping.
  	 * However, empty mask means pin synchronization is desired. */
  	if (mask && (jack->status == oldstatus))

  		goto out;

  	trace_snd_soc_jack_notify(jack, status);

  	list_for_each_entry(pin, &jack->pins, list) {

  		enable = pin->mask & jack->status;

  
  		if (pin->invert)
  			enable = !enable;
  
  		if (enable)

  			snd_soc_dapm_enable_pin(dapm, pin->pin);

  		else

  			snd_soc_dapm_disable_pin(dapm, pin->pin);

  	}

  	/* Report before the DAPM sync to help users updating micbias status */

  	blocking_notifier_call_chain(&jack->notifier, status, jack);

  	snd_soc_dapm_sync(dapm);

  	snd_jack_report(jack->jack, jack->status);

  
  out:
  	mutex_unlock(&codec->mutex);
  }
  EXPORT_SYMBOL_GPL(snd_soc_jack_report);
  
  /**

   * snd_soc_jack_add_zones - Associate voltage zones with jack
   *
   * @jack:  ASoC jack
   * @count: Number of zones
   * @zone:  Array of zones
   *
   * After this function has been called the zones specified in the
   * array will be associated with the jack.
   */
  int snd_soc_jack_add_zones(struct snd_soc_jack *jack, int count,
  			  struct snd_soc_jack_zone *zones)
  {
  	int i;
  
  	for (i = 0; i < count; i++) {
  		INIT_LIST_HEAD(&zones[i].list);
  		list_add(&(zones[i].list), &jack->jack_zones);
  	}
  	return 0;
  }
  EXPORT_SYMBOL_GPL(snd_soc_jack_add_zones);
  
  /**
   * snd_soc_jack_get_type - Based on the mic bias value, this function returns
   * the type of jack from the zones delcared in the jack type
   *
   * @micbias_voltage:  mic bias voltage at adc channel when jack is plugged in
   *
   * Based on the mic bias value passed, this function helps identify
   * the type of jack from the already delcared jack zones
   */
  int snd_soc_jack_get_type(struct snd_soc_jack *jack, int micbias_voltage)
  {
  	struct snd_soc_jack_zone *zone;
  
  	list_for_each_entry(zone, &jack->jack_zones, list) {
  		if (micbias_voltage >= zone->min_mv &&
  			micbias_voltage < zone->max_mv)
  				return zone->jack_type;
  	}
  	return 0;
  }
  EXPORT_SYMBOL_GPL(snd_soc_jack_get_type);
  
  /**

   * snd_soc_jack_add_pins - Associate DAPM pins with an ASoC jack
   *
   * @jack:  ASoC jack
   * @count: Number of pins
   * @pins:  Array of pins
   *
   * After this function has been called the DAPM pins specified in the
   * pins array will have their status updated to reflect the current
   * state of the jack whenever the jack status is updated.
   */
  int snd_soc_jack_add_pins(struct snd_soc_jack *jack, int count,
  			  struct snd_soc_jack_pin *pins)
  {
  	int i;
  
  	for (i = 0; i < count; i++) {
  		if (!pins[i].pin) {
  			printk(KERN_ERR "No name for pin %d
  ", i);
  			return -EINVAL;
  		}
  		if (!pins[i].mask) {
  			printk(KERN_ERR "No mask for pin %d (%s)
  ", i,
  			       pins[i].pin);
  			return -EINVAL;
  		}
  
  		INIT_LIST_HEAD(&pins[i].list);
  		list_add(&(pins[i].list), &jack->pins);
  	}

  	snd_soc_dapm_new_widgets(&jack->codec->card->dapm);

  	/* Update to reflect the last reported status; canned jack
  	 * implementations are likely to set their state before the
  	 * card has an opportunity to associate pins.
  	 */
  	snd_soc_jack_report(jack, 0, 0);
  
  	return 0;
  }
  EXPORT_SYMBOL_GPL(snd_soc_jack_add_pins);

  /**
   * snd_soc_jack_notifier_register - Register a notifier for jack status
   *
   * @jack:  ASoC jack
   * @nb:    Notifier block to register
   *
   * Register for notification of the current status of the jack.  Note
   * that it is not possible to report additional jack events in the
   * callback from the notifier, this is intended to support
   * applications such as enabling electrical detection only when a
   * mechanical detection event has occurred.
   */
  void snd_soc_jack_notifier_register(struct snd_soc_jack *jack,
  				    struct notifier_block *nb)
  {
  	blocking_notifier_chain_register(&jack->notifier, nb);
  }
  EXPORT_SYMBOL_GPL(snd_soc_jack_notifier_register);
  
  /**
   * snd_soc_jack_notifier_unregister - Unregister a notifier for jack status
   *
   * @jack:  ASoC jack
   * @nb:    Notifier block to unregister
   *
   * Stop notifying for status changes.
   */
  void snd_soc_jack_notifier_unregister(struct snd_soc_jack *jack,
  				      struct notifier_block *nb)
  {
  	blocking_notifier_chain_unregister(&jack->notifier, nb);
  }
  EXPORT_SYMBOL_GPL(snd_soc_jack_notifier_unregister);

  #ifdef CONFIG_GPIOLIB
  /* gpio detect */

  static void snd_soc_jack_gpio_detect(struct snd_soc_jack_gpio *gpio)

  {
  	struct snd_soc_jack *jack = gpio->jack;
  	int enable;
  	int report;

  	enable = gpio_get_value_cansleep(gpio->gpio);

  	if (gpio->invert)
  		enable = !enable;
  
  	if (enable)
  		report = gpio->report;
  	else
  		report = 0;

  	if (gpio->jack_status_check)
  		report = gpio->jack_status_check();

  	snd_soc_jack_report(jack, report, gpio->report);
  }
  
  /* irq handler for gpio pin */
  static irqreturn_t gpio_handler(int irq, void *data)
  {
  	struct snd_soc_jack_gpio *gpio = data;

  	struct device *dev = gpio->jack->codec->card->dev;

  	trace_snd_soc_jack_irq(gpio->name);

  	if (device_may_wakeup(dev))
  		pm_wakeup_event(dev, gpio->debounce_time + 50);

  	schedule_delayed_work(&gpio->work,
  			      msecs_to_jiffies(gpio->debounce_time));

  
  	return IRQ_HANDLED;
  }
  
  /* gpio work */
  static void gpio_work(struct work_struct *work)
  {
  	struct snd_soc_jack_gpio *gpio;

  	gpio = container_of(work, struct snd_soc_jack_gpio, work.work);

  	snd_soc_jack_gpio_detect(gpio);
  }
  
  /**
   * snd_soc_jack_add_gpios - Associate GPIO pins with an ASoC jack
   *
   * @jack:  ASoC jack
   * @count: number of pins
   * @gpios: array of gpio pins
   *
   * This function will request gpio, set data direction and request irq
   * for each gpio in the array.
   */
  int snd_soc_jack_add_gpios(struct snd_soc_jack *jack, int count,
  			struct snd_soc_jack_gpio *gpios)
  {
  	int i, ret;
  
  	for (i = 0; i < count; i++) {
  		if (!gpio_is_valid(gpios[i].gpio)) {
  			printk(KERN_ERR "Invalid gpio %d
  ",
  				gpios[i].gpio);
  			ret = -EINVAL;
  			goto undo;
  		}
  		if (!gpios[i].name) {
  			printk(KERN_ERR "No name for gpio %d
  ",
  				gpios[i].gpio);
  			ret = -EINVAL;
  			goto undo;
  		}
  
  		ret = gpio_request(gpios[i].gpio, gpios[i].name);
  		if (ret)
  			goto undo;
  
  		ret = gpio_direction_input(gpios[i].gpio);
  		if (ret)
  			goto err;

  		INIT_DELAYED_WORK(&gpios[i].work, gpio_work);

  		gpios[i].jack = jack;

  		ret = request_any_context_irq(gpio_to_irq(gpios[i].gpio),
  					      gpio_handler,
  					      IRQF_TRIGGER_RISING |
  					      IRQF_TRIGGER_FALLING,

  					      gpios[i].name,

  					      &gpios[i]);

  		if (ret < 0)

  			goto err;

  		if (gpios[i].wake) {

  			ret = irq_set_irq_wake(gpio_to_irq(gpios[i].gpio), 1);

  			if (ret != 0)
  				printk(KERN_ERR
  				  "Failed to mark GPIO %d as wake source: %d
  ",
  					gpios[i].gpio, ret);
  		}

  		/* Expose GPIO value over sysfs for diagnostic purposes */
  		gpio_export(gpios[i].gpio, false);

  		/* Update initial jack status */
  		snd_soc_jack_gpio_detect(&gpios[i]);

  	}
  
  	return 0;
  
  err:
  	gpio_free(gpios[i].gpio);
  undo:
  	snd_soc_jack_free_gpios(jack, i, gpios);
  
  	return ret;
  }
  EXPORT_SYMBOL_GPL(snd_soc_jack_add_gpios);
  
  /**
   * snd_soc_jack_free_gpios - Release GPIO pins' resources of an ASoC jack
   *
   * @jack:  ASoC jack
   * @count: number of pins
   * @gpios: array of gpio pins
   *
   * Release gpio and irq resources for gpio pins associated with an ASoC jack.
   */
  void snd_soc_jack_free_gpios(struct snd_soc_jack *jack, int count,
  			struct snd_soc_jack_gpio *gpios)
  {
  	int i;
  
  	for (i = 0; i < count; i++) {

  		gpio_unexport(gpios[i].gpio);

  		free_irq(gpio_to_irq(gpios[i].gpio), &gpios[i]);

  		cancel_delayed_work_sync(&gpios[i].work);

  		gpio_free(gpios[i].gpio);
  		gpios[i].jack = NULL;
  	}
  }
  EXPORT_SYMBOL_GPL(snd_soc_jack_free_gpios);
  #endif	/* CONFIG_GPIOLIB */