ASoC: jack - check status of GPIO-based pins on resume

[mirror_ubuntu-artful-kernel.git] / sound / soc / soc-jack.c

/*
 * 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/gpio/consumer.h>
#include <linux/interrupt.h>
#include <linux/workqueue.h>
#include <linux/delay.h>
#include <linux/export.h>
#include <linux/suspend.h>
#include <trace/events/asoc.h>

/**
 * snd_soc_card_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
 * @pins:  Array of jack pins to be added to the jack or NULL
 * @num_pins: Number of elements in the @pins array
 *
 * 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_card_jack_new(struct snd_soc_card *card, const char *id, int type,
        struct snd_soc_jack *jack, struct snd_soc_jack_pin *pins,
        unsigned int num_pins)
{
        int ret;

        mutex_init(&jack->mutex);
        jack->card = card;
        INIT_LIST_HEAD(&jack->pins);
        INIT_LIST_HEAD(&jack->jack_zones);
        BLOCKING_INIT_NOTIFIER_HEAD(&jack->notifier);

        ret = snd_jack_new(card->snd_card, id, type, &jack->jack, false, false);
        if (ret)
                return ret;

        if (num_pins)
                return snd_soc_jack_add_pins(jack, num_pins, pins);

        return 0;
}
EXPORT_SYMBOL_GPL(snd_soc_card_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_dapm_context *dapm;
        struct snd_soc_jack_pin *pin;
        unsigned int sync = 0;
        int enable;

        trace_snd_soc_jack_report(jack, mask, status);

        if (!jack)
                return;

        dapm = &jack->card->dapm;

        mutex_lock(&jack->mutex);

        jack->status &= ~mask;
        jack->status |= status & mask;

        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);

                /* we need to sync for this case only */
                sync = 1;
        }

        /* Report before the DAPM sync to help users updating micbias status */
        blocking_notifier_call_chain(&jack->notifier, jack->status, jack);

        if (sync)
                snd_soc_dapm_sync(dapm);

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

        mutex_unlock(&jack->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
 * @zones:  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 declared in the jack type
 *
 * @jack:  ASoC jack
 * @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 declared 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) {
                        dev_err(jack->card->dev, "ASoC: No name for pin %d\n",
                                i);
                        return -EINVAL;
                }
                if (!pins[i].mask) {
                        dev_err(jack->card->dev, "ASoC: No mask for pin %d"
                                " (%s)\n", i, pins[i].pin);
                        return -EINVAL;
                }

                INIT_LIST_HEAD(&pins[i].list);
                list_add(&(pins[i].list), &jack->pins);
                snd_jack_add_new_kctl(jack->jack, pins[i].pin, pins[i].mask);
        }

        /* 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 = gpiod_get_value_cansleep(gpio->desc);
        if (gpio->invert)
                enable = !enable;

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

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

        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->card->dev;

        trace_snd_soc_jack_irq(gpio->name);

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

        queue_delayed_work(system_power_efficient_wq, &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);
}

static int snd_soc_jack_pm_notifier(struct notifier_block *nb,
                                    unsigned long action, void *data)
{
        struct snd_soc_jack_gpio *gpio =
                        container_of(nb, struct snd_soc_jack_gpio, pm_notifier);

        switch (action) {
        case PM_POST_SUSPEND:
        case PM_POST_HIBERNATION:
        case PM_POST_RESTORE:
                /*
                 * Use workqueue so we do not have to care about running
                 * concurrently with work triggered by the interrupt handler.
                 */
                queue_delayed_work(system_power_efficient_wq, &gpio->work, 0);
                break;
        }

        return NOTIFY_DONE;
}

/**
 * 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 (!gpios[i].name) {
                        dev_err(jack->card->dev,
                                "ASoC: No name for gpio at index %d\n", i);
                        ret = -EINVAL;
                        goto undo;
                }

                if (gpios[i].desc) {
                        /* Already have a GPIO descriptor. */
                        goto got_gpio;
                } else if (gpios[i].gpiod_dev) {
                        /* Get a GPIO descriptor */
                        gpios[i].desc = gpiod_get_index(gpios[i].gpiod_dev,
                                                        gpios[i].name,
                                                        gpios[i].idx, GPIOD_IN);
                        if (IS_ERR(gpios[i].desc)) {
                                ret = PTR_ERR(gpios[i].desc);
                                dev_err(gpios[i].gpiod_dev,
                                        "ASoC: Cannot get gpio at index %d: %d",
                                        i, ret);
                                goto undo;
                        }
                } else {
                        /* legacy GPIO number */
                        if (!gpio_is_valid(gpios[i].gpio)) {
                                dev_err(jack->card->dev,
                                        "ASoC: Invalid gpio %d\n",
                                        gpios[i].gpio);
                                ret = -EINVAL;
                                goto undo;
                        }

                        ret = gpio_request_one(gpios[i].gpio, GPIOF_IN,
                                               gpios[i].name);
                        if (ret)
                                goto undo;

                        gpios[i].desc = gpio_to_desc(gpios[i].gpio);
                }
got_gpio:
                INIT_DELAYED_WORK(&gpios[i].work, gpio_work);
                gpios[i].jack = jack;

                ret = request_any_context_irq(gpiod_to_irq(gpios[i].desc),
                                              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(gpiod_to_irq(gpios[i].desc), 1);
                        if (ret != 0)
                                dev_err(jack->card->dev,
                                        "ASoC: Failed to mark GPIO at index %d as wake source: %d\n",
                                        i, ret);
                }

                /*
                 * Register PM notifier so we do not miss state transitions
                 * happening while system is asleep.
                 */
                gpios[i].pm_notifier.notifier_call = snd_soc_jack_pm_notifier;
                register_pm_notifier(&gpios[i].pm_notifier);

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

                /* Update initial jack status */
                schedule_delayed_work(&gpios[i].work,
                                      msecs_to_jiffies(gpios[i].debounce_time));
        }

        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_add_gpiods - Associate GPIO descriptor pins with an ASoC jack
 *
 * @gpiod_dev: GPIO consumer device
 * @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_gpiods(struct device *gpiod_dev,
                            struct snd_soc_jack *jack,
                            int count, struct snd_soc_jack_gpio *gpios)
{
        int i;

        for (i = 0; i < count; i++)
                gpios[i].gpiod_dev = gpiod_dev;

        return snd_soc_jack_add_gpios(jack, count, gpios);
}
EXPORT_SYMBOL_GPL(snd_soc_jack_add_gpiods);

/**
 * 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++) {
                gpiod_unexport(gpios[i].desc);
                unregister_pm_notifier(&gpios[i].pm_notifier);
                free_irq(gpiod_to_irq(gpios[i].desc), &gpios[i]);
                cancel_delayed_work_sync(&gpios[i].work);
                gpiod_put(gpios[i].desc);
                gpios[i].jack = NULL;
        }
}
EXPORT_SYMBOL_GPL(snd_soc_jack_free_gpios);
#endif  /* CONFIG_GPIOLIB */