linux/sound/soc/soc-jack.c
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   1/*
   2 * soc-jack.c  --  ALSA SoC jack handling
   3 *
   4 * Copyright 2008 Wolfson Microelectronics PLC.
   5 *
   6 * Author: Mark Brown <broonie@opensource.wolfsonmicro.com>
   7 *
   8 *  This program is free software; you can redistribute  it and/or modify it
   9 *  under  the terms of  the GNU General  Public License as published by the
  10 *  Free Software Foundation;  either version 2 of the  License, or (at your
  11 *  option) any later version.
  12 */
  13
  14#include <sound/jack.h>
  15#include <sound/soc.h>
  16#include <linux/gpio.h>
  17#include <linux/interrupt.h>
  18#include <linux/workqueue.h>
  19#include <linux/delay.h>
  20#include <linux/export.h>
  21#include <trace/events/asoc.h>
  22
  23/**
  24 * snd_soc_jack_new - Create a new jack
  25 * @card:  ASoC card
  26 * @id:    an identifying string for this jack
  27 * @type:  a bitmask of enum snd_jack_type values that can be detected by
  28 *         this jack
  29 * @jack:  structure to use for the jack
  30 *
  31 * Creates a new jack object.
  32 *
  33 * Returns zero if successful, or a negative error code on failure.
  34 * On success jack will be initialised.
  35 */
  36int snd_soc_jack_new(struct snd_soc_codec *codec, const char *id, int type,
  37                     struct snd_soc_jack *jack)
  38{
  39        mutex_init(&jack->mutex);
  40        jack->codec = codec;
  41        INIT_LIST_HEAD(&jack->pins);
  42        INIT_LIST_HEAD(&jack->jack_zones);
  43        BLOCKING_INIT_NOTIFIER_HEAD(&jack->notifier);
  44
  45        return snd_jack_new(codec->card->snd_card, id, type, &jack->jack);
  46}
  47EXPORT_SYMBOL_GPL(snd_soc_jack_new);
  48
  49/**
  50 * snd_soc_jack_report - Report the current status for a jack
  51 *
  52 * @jack:   the jack
  53 * @status: a bitmask of enum snd_jack_type values that are currently detected.
  54 * @mask:   a bitmask of enum snd_jack_type values that being reported.
  55 *
  56 * If configured using snd_soc_jack_add_pins() then the associated
  57 * DAPM pins will be enabled or disabled as appropriate and DAPM
  58 * synchronised.
  59 *
  60 * Note: This function uses mutexes and should be called from a
  61 * context which can sleep (such as a workqueue).
  62 */
  63void snd_soc_jack_report(struct snd_soc_jack *jack, int status, int mask)
  64{
  65        struct snd_soc_codec *codec;
  66        struct snd_soc_dapm_context *dapm;
  67        struct snd_soc_jack_pin *pin;
  68        int enable;
  69        int oldstatus;
  70
  71        trace_snd_soc_jack_report(jack, mask, status);
  72
  73        if (!jack)
  74                return;
  75
  76        codec = jack->codec;
  77        dapm =  &codec->dapm;
  78
  79        mutex_lock(&jack->mutex);
  80
  81        oldstatus = jack->status;
  82
  83        jack->status &= ~mask;
  84        jack->status |= status & mask;
  85
  86        /* The DAPM sync is expensive enough to be worth skipping.
  87         * However, empty mask means pin synchronization is desired. */
  88        if (mask && (jack->status == oldstatus))
  89                goto out;
  90
  91        trace_snd_soc_jack_notify(jack, status);
  92
  93        list_for_each_entry(pin, &jack->pins, list) {
  94                enable = pin->mask & jack->status;
  95
  96                if (pin->invert)
  97                        enable = !enable;
  98
  99                if (enable)
 100                        snd_soc_dapm_enable_pin(dapm, pin->pin);
 101                else
 102                        snd_soc_dapm_disable_pin(dapm, pin->pin);
 103        }
 104
 105        /* Report before the DAPM sync to help users updating micbias status */
 106        blocking_notifier_call_chain(&jack->notifier, jack->status, jack);
 107
 108        snd_soc_dapm_sync(dapm);
 109
 110        snd_jack_report(jack->jack, jack->status);
 111
 112out:
 113        mutex_unlock(&jack->mutex);
 114}
 115EXPORT_SYMBOL_GPL(snd_soc_jack_report);
 116
 117/**
 118 * snd_soc_jack_add_zones - Associate voltage zones with jack
 119 *
 120 * @jack:  ASoC jack
 121 * @count: Number of zones
 122 * @zone:  Array of zones
 123 *
 124 * After this function has been called the zones specified in the
 125 * array will be associated with the jack.
 126 */
 127int snd_soc_jack_add_zones(struct snd_soc_jack *jack, int count,
 128                          struct snd_soc_jack_zone *zones)
 129{
 130        int i;
 131
 132        for (i = 0; i < count; i++) {
 133                INIT_LIST_HEAD(&zones[i].list);
 134                list_add(&(zones[i].list), &jack->jack_zones);
 135        }
 136        return 0;
 137}
 138EXPORT_SYMBOL_GPL(snd_soc_jack_add_zones);
 139
 140/**
 141 * snd_soc_jack_get_type - Based on the mic bias value, this function returns
 142 * the type of jack from the zones delcared in the jack type
 143 *
 144 * @micbias_voltage:  mic bias voltage at adc channel when jack is plugged in
 145 *
 146 * Based on the mic bias value passed, this function helps identify
 147 * the type of jack from the already delcared jack zones
 148 */
 149int snd_soc_jack_get_type(struct snd_soc_jack *jack, int micbias_voltage)
 150{
 151        struct snd_soc_jack_zone *zone;
 152
 153        list_for_each_entry(zone, &jack->jack_zones, list) {
 154                if (micbias_voltage >= zone->min_mv &&
 155                        micbias_voltage < zone->max_mv)
 156                                return zone->jack_type;
 157        }
 158        return 0;
 159}
 160EXPORT_SYMBOL_GPL(snd_soc_jack_get_type);
 161
 162/**
 163 * snd_soc_jack_add_pins - Associate DAPM pins with an ASoC jack
 164 *
 165 * @jack:  ASoC jack
 166 * @count: Number of pins
 167 * @pins:  Array of pins
 168 *
 169 * After this function has been called the DAPM pins specified in the
 170 * pins array will have their status updated to reflect the current
 171 * state of the jack whenever the jack status is updated.
 172 */
 173int snd_soc_jack_add_pins(struct snd_soc_jack *jack, int count,
 174                          struct snd_soc_jack_pin *pins)
 175{
 176        int i;
 177
 178        for (i = 0; i < count; i++) {
 179                if (!pins[i].pin) {
 180                        printk(KERN_ERR "No name for pin %d\n", i);
 181                        return -EINVAL;
 182                }
 183                if (!pins[i].mask) {
 184                        printk(KERN_ERR "No mask for pin %d (%s)\n", i,
 185                               pins[i].pin);
 186                        return -EINVAL;
 187                }
 188
 189                INIT_LIST_HEAD(&pins[i].list);
 190                list_add(&(pins[i].list), &jack->pins);
 191        }
 192
 193        snd_soc_dapm_new_widgets(&jack->codec->card->dapm);
 194
 195        /* Update to reflect the last reported status; canned jack
 196         * implementations are likely to set their state before the
 197         * card has an opportunity to associate pins.
 198         */
 199        snd_soc_jack_report(jack, 0, 0);
 200
 201        return 0;
 202}
 203EXPORT_SYMBOL_GPL(snd_soc_jack_add_pins);
 204
 205/**
 206 * snd_soc_jack_notifier_register - Register a notifier for jack status
 207 *
 208 * @jack:  ASoC jack
 209 * @nb:    Notifier block to register
 210 *
 211 * Register for notification of the current status of the jack.  Note
 212 * that it is not possible to report additional jack events in the
 213 * callback from the notifier, this is intended to support
 214 * applications such as enabling electrical detection only when a
 215 * mechanical detection event has occurred.
 216 */
 217void snd_soc_jack_notifier_register(struct snd_soc_jack *jack,
 218                                    struct notifier_block *nb)
 219{
 220        blocking_notifier_chain_register(&jack->notifier, nb);
 221}
 222EXPORT_SYMBOL_GPL(snd_soc_jack_notifier_register);
 223
 224/**
 225 * snd_soc_jack_notifier_unregister - Unregister a notifier for jack status
 226 *
 227 * @jack:  ASoC jack
 228 * @nb:    Notifier block to unregister
 229 *
 230 * Stop notifying for status changes.
 231 */
 232void snd_soc_jack_notifier_unregister(struct snd_soc_jack *jack,
 233                                      struct notifier_block *nb)
 234{
 235        blocking_notifier_chain_unregister(&jack->notifier, nb);
 236}
 237EXPORT_SYMBOL_GPL(snd_soc_jack_notifier_unregister);
 238
 239#ifdef CONFIG_GPIOLIB
 240/* gpio detect */
 241static void snd_soc_jack_gpio_detect(struct snd_soc_jack_gpio *gpio)
 242{
 243        struct snd_soc_jack *jack = gpio->jack;
 244        int enable;
 245        int report;
 246
 247        enable = gpio_get_value_cansleep(gpio->gpio);
 248        if (gpio->invert)
 249                enable = !enable;
 250
 251        if (enable)
 252                report = gpio->report;
 253        else
 254                report = 0;
 255
 256        if (gpio->jack_status_check)
 257                report = gpio->jack_status_check();
 258
 259        snd_soc_jack_report(jack, report, gpio->report);
 260}
 261
 262/* irq handler for gpio pin */
 263static irqreturn_t gpio_handler(int irq, void *data)
 264{
 265        struct snd_soc_jack_gpio *gpio = data;
 266        struct device *dev = gpio->jack->codec->card->dev;
 267
 268        trace_snd_soc_jack_irq(gpio->name);
 269
 270        if (device_may_wakeup(dev))
 271                pm_wakeup_event(dev, gpio->debounce_time + 50);
 272
 273        schedule_delayed_work(&gpio->work,
 274                              msecs_to_jiffies(gpio->debounce_time));
 275
 276        return IRQ_HANDLED;
 277}
 278
 279/* gpio work */
 280static void gpio_work(struct work_struct *work)
 281{
 282        struct snd_soc_jack_gpio *gpio;
 283
 284        gpio = container_of(work, struct snd_soc_jack_gpio, work.work);
 285        snd_soc_jack_gpio_detect(gpio);
 286}
 287
 288/**
 289 * snd_soc_jack_add_gpios - Associate GPIO pins with an ASoC jack
 290 *
 291 * @jack:  ASoC jack
 292 * @count: number of pins
 293 * @gpios: array of gpio pins
 294 *
 295 * This function will request gpio, set data direction and request irq
 296 * for each gpio in the array.
 297 */
 298int snd_soc_jack_add_gpios(struct snd_soc_jack *jack, int count,
 299                        struct snd_soc_jack_gpio *gpios)
 300{
 301        int i, ret;
 302
 303        for (i = 0; i < count; i++) {
 304                if (!gpio_is_valid(gpios[i].gpio)) {
 305                        printk(KERN_ERR "Invalid gpio %d\n",
 306                                gpios[i].gpio);
 307                        ret = -EINVAL;
 308                        goto undo;
 309                }
 310                if (!gpios[i].name) {
 311                        printk(KERN_ERR "No name for gpio %d\n",
 312                                gpios[i].gpio);
 313                        ret = -EINVAL;
 314                        goto undo;
 315                }
 316
 317                ret = gpio_request(gpios[i].gpio, gpios[i].name);
 318                if (ret)
 319                        goto undo;
 320
 321                ret = gpio_direction_input(gpios[i].gpio);
 322                if (ret)
 323                        goto err;
 324
 325                INIT_DELAYED_WORK(&gpios[i].work, gpio_work);
 326                gpios[i].jack = jack;
 327
 328                ret = request_any_context_irq(gpio_to_irq(gpios[i].gpio),
 329                                              gpio_handler,
 330                                              IRQF_TRIGGER_RISING |
 331                                              IRQF_TRIGGER_FALLING,
 332                                              gpios[i].name,
 333                                              &gpios[i]);
 334                if (ret < 0)
 335                        goto err;
 336
 337                if (gpios[i].wake) {
 338                        ret = irq_set_irq_wake(gpio_to_irq(gpios[i].gpio), 1);
 339                        if (ret != 0)
 340                                printk(KERN_ERR
 341                                  "Failed to mark GPIO %d as wake source: %d\n",
 342                                        gpios[i].gpio, ret);
 343                }
 344
 345                /* Expose GPIO value over sysfs for diagnostic purposes */
 346                gpio_export(gpios[i].gpio, false);
 347
 348                /* Update initial jack status */
 349                snd_soc_jack_gpio_detect(&gpios[i]);
 350        }
 351
 352        return 0;
 353
 354err:
 355        gpio_free(gpios[i].gpio);
 356undo:
 357        snd_soc_jack_free_gpios(jack, i, gpios);
 358
 359        return ret;
 360}
 361EXPORT_SYMBOL_GPL(snd_soc_jack_add_gpios);
 362
 363/**
 364 * snd_soc_jack_free_gpios - Release GPIO pins' resources of an ASoC jack
 365 *
 366 * @jack:  ASoC jack
 367 * @count: number of pins
 368 * @gpios: array of gpio pins
 369 *
 370 * Release gpio and irq resources for gpio pins associated with an ASoC jack.
 371 */
 372void snd_soc_jack_free_gpios(struct snd_soc_jack *jack, int count,
 373                        struct snd_soc_jack_gpio *gpios)
 374{
 375        int i;
 376
 377        for (i = 0; i < count; i++) {
 378                gpio_unexport(gpios[i].gpio);
 379                free_irq(gpio_to_irq(gpios[i].gpio), &gpios[i]);
 380                cancel_delayed_work_sync(&gpios[i].work);
 381                gpio_free(gpios[i].gpio);
 382                gpios[i].jack = NULL;
 383        }
 384}
 385EXPORT_SYMBOL_GPL(snd_soc_jack_free_gpios);
 386#endif  /* CONFIG_GPIOLIB */
 387
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