sound/soc/soc-jack.c

   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 <trace/events/asoc.h>
  21
  22 /**
  23  * snd_soc_jack_new - Create a new jack
  24  * @card:  ASoC card
  25  * @id:    an identifying string for this jack
  26  * @type:  a bitmask of enum snd_jack_type values that can be detected by
  27  *         this jack
  28  * @jack:  structure to use for the jack
  29  *
  30  * Creates a new jack object.
  31  *
  32  * Returns zero if successful, or a negative error code on failure.
  33  * On success jack will be initialised.
  34  */
  35 int snd_soc_jack_new(struct snd_soc_codec *codec, const char *id, int type,
  36                      struct snd_soc_jack *jack)
  37 {
  38         jack->codec = codec;
  39         INIT_LIST_HEAD(&jack->pins);
  40         BLOCKING_INIT_NOTIFIER_HEAD(&jack->notifier);
  41
  42         return snd_jack_new(codec->card->snd_card, id, type, &jack->jack);
  43 }
  44 EXPORT_SYMBOL_GPL(snd_soc_jack_new);
  45
  46 /**
  47  * snd_soc_jack_report - Report the current status for a jack
  48  *
  49  * @jack:   the jack
  50  * @status: a bitmask of enum snd_jack_type values that are currently detected.
  51  * @mask:   a bitmask of enum snd_jack_type values that being reported.
  52  *
  53  * If configured using snd_soc_jack_add_pins() then the associated
  54  * DAPM pins will be enabled or disabled as appropriate and DAPM
  55  * synchronised.
  56  *
  57  * Note: This function uses mutexes and should be called from a
  58  * context which can sleep (such as a workqueue).
  59  */
  60 void snd_soc_jack_report(struct snd_soc_jack *jack, int status, int mask)
  61 {
  62         struct snd_soc_codec *codec;
  63         struct snd_soc_dapm_context *dapm;
  64         struct snd_soc_jack_pin *pin;
  65         int enable;
  66         int oldstatus;
  67
  68         trace_snd_soc_jack_report(jack, mask, status);
  69
  70         if (!jack)
  71                 return;
  72
  73         codec = jack->codec;
  74         dapm =  &codec->dapm;
  75
  76         mutex_lock(&codec->mutex);
  77
  78         oldstatus = jack->status;
  79
  80         jack->status &= ~mask;
  81         jack->status |= status & mask;
  82
  83         /* The DAPM sync is expensive enough to be worth skipping.
  84          * However, empty mask means pin synchronization is desired. */
  85         if (mask && (jack->status == oldstatus))
  86                 goto out;
  87
  88         trace_snd_soc_jack_notify(jack, status);
  89
  90         list_for_each_entry(pin, &jack->pins, list) {
  91                 enable = pin->mask & jack->status;
  92
  93                 if (pin->invert)
  94                         enable = !enable;
  95
  96                 if (enable)
  97                         snd_soc_dapm_enable_pin(dapm, pin->pin);
  98                 else
  99                         snd_soc_dapm_disable_pin(dapm, pin->pin);
 100         }
 101
 102         /* Report before the DAPM sync to help users updating micbias status */
 103         blocking_notifier_call_chain(&jack->notifier, status, NULL);
 104
 105         snd_soc_dapm_sync(dapm);
 106
 107         snd_jack_report(jack->jack, status);
 108
 109 out:
 110         mutex_unlock(&codec->mutex);
 111 }
 112 EXPORT_SYMBOL_GPL(snd_soc_jack_report);
 113
 114 /**
 115  * snd_soc_jack_add_pins - Associate DAPM pins with an ASoC jack
 116  *
 117  * @jack:  ASoC jack
 118  * @count: Number of pins
 119  * @pins:  Array of pins
 120  *
 121  * After this function has been called the DAPM pins specified in the
 122  * pins array will have their status updated to reflect the current
 123  * state of the jack whenever the jack status is updated.
 124  */
 125 int snd_soc_jack_add_pins(struct snd_soc_jack *jack, int count,
 126                           struct snd_soc_jack_pin *pins)
 127 {
 128         int i;
 129
 130         for (i = 0; i < count; i++) {
 131                 if (!pins[i].pin) {
 132                         printk(KERN_ERR "No name for pin %d\n", i);
 133                         return -EINVAL;
 134                 }
 135                 if (!pins[i].mask) {
 136                         printk(KERN_ERR "No mask for pin %d (%s)\n", i,
 137                                pins[i].pin);
 138                         return -EINVAL;
 139                 }
 140
 141                 INIT_LIST_HEAD(&pins[i].list);
 142                 list_add(&(pins[i].list), &jack->pins);
 143         }
 144
 145         /* Update to reflect the last reported status; canned jack
 146          * implementations are likely to set their state before the
 147          * card has an opportunity to associate pins.
 148          */
 149         snd_soc_jack_report(jack, 0, 0);
 150
 151         return 0;
 152 }
 153 EXPORT_SYMBOL_GPL(snd_soc_jack_add_pins);
 154
 155 /**
 156  * snd_soc_jack_notifier_register - Register a notifier for jack status
 157  *
 158  * @jack:  ASoC jack
 159  * @nb:    Notifier block to register
 160  *
 161  * Register for notification of the current status of the jack.  Note
 162  * that it is not possible to report additional jack events in the
 163  * callback from the notifier, this is intended to support
 164  * applications such as enabling electrical detection only when a
 165  * mechanical detection event has occurred.
 166  */
 167 void snd_soc_jack_notifier_register(struct snd_soc_jack *jack,
 168                                     struct notifier_block *nb)
 169 {
 170         blocking_notifier_chain_register(&jack->notifier, nb);
 171 }
 172 EXPORT_SYMBOL_GPL(snd_soc_jack_notifier_register);
 173
 174 /**
 175  * snd_soc_jack_notifier_unregister - Unregister a notifier for jack status
 176  *
 177  * @jack:  ASoC jack
 178  * @nb:    Notifier block to unregister
 179  *
 180  * Stop notifying for status changes.
 181  */
 182 void snd_soc_jack_notifier_unregister(struct snd_soc_jack *jack,
 183                                       struct notifier_block *nb)
 184 {
 185         blocking_notifier_chain_unregister(&jack->notifier, nb);
 186 }
 187 EXPORT_SYMBOL_GPL(snd_soc_jack_notifier_unregister);
 188
 189 #ifdef CONFIG_GPIOLIB
 190 /* gpio detect */
 191 static void snd_soc_jack_gpio_detect(struct snd_soc_jack_gpio *gpio)
 192 {
 193         struct snd_soc_jack *jack = gpio->jack;
 194         int enable;
 195         int report;
 196
 197         enable = gpio_get_value(gpio->gpio);
 198         if (gpio->invert)
 199                 enable = !enable;
 200
 201         if (enable)
 202                 report = gpio->report;
 203         else
 204                 report = 0;
 205
 206         if (gpio->jack_status_check)
 207                 report = gpio->jack_status_check();
 208
 209         snd_soc_jack_report(jack, report, gpio->report);
 210 }
 211
 212 /* irq handler for gpio pin */
 213 static irqreturn_t gpio_handler(int irq, void *data)
 214 {
 215         struct snd_soc_jack_gpio *gpio = data;
 216         struct device *dev = gpio->jack->codec->card->dev;
 217
 218         trace_snd_soc_jack_irq(gpio->name);
 219
 220         if (device_may_wakeup(dev))
 221                 pm_wakeup_event(dev, gpio->debounce_time + 50);
 222
 223         schedule_delayed_work(&gpio->work,
 224                               msecs_to_jiffies(gpio->debounce_time));
 225
 226         return IRQ_HANDLED;
 227 }
 228
 229 /* gpio work */
 230 static void gpio_work(struct work_struct *work)
 231 {
 232         struct snd_soc_jack_gpio *gpio;
 233
 234         gpio = container_of(work, struct snd_soc_jack_gpio, work.work);
 235         snd_soc_jack_gpio_detect(gpio);
 236 }
 237
 238 /**
 239  * snd_soc_jack_add_gpios - Associate GPIO pins with an ASoC jack
 240  *
 241  * @jack:  ASoC jack
 242  * @count: number of pins
 243  * @gpios: array of gpio pins
 244  *
 245  * This function will request gpio, set data direction and request irq
 246  * for each gpio in the array.
 247  */
 248 int snd_soc_jack_add_gpios(struct snd_soc_jack *jack, int count,
 249                         struct snd_soc_jack_gpio *gpios)
 250 {
 251         int i, ret;
 252
 253         for (i = 0; i < count; i++) {
 254                 if (!gpio_is_valid(gpios[i].gpio)) {
 255                         printk(KERN_ERR "Invalid gpio %d\n",
 256                                 gpios[i].gpio);
 257                         ret = -EINVAL;
 258                         goto undo;
 259                 }
 260                 if (!gpios[i].name) {
 261                         printk(KERN_ERR "No name for gpio %d\n",
 262                                 gpios[i].gpio);
 263                         ret = -EINVAL;
 264                         goto undo;
 265                 }
 266
 267                 ret = gpio_request(gpios[i].gpio, gpios[i].name);
 268                 if (ret)
 269                         goto undo;
 270
 271                 ret = gpio_direction_input(gpios[i].gpio);
 272                 if (ret)
 273                         goto err;
 274
 275                 INIT_DELAYED_WORK(&gpios[i].work, gpio_work);
 276                 gpios[i].jack = jack;
 277
 278                 ret = request_any_context_irq(gpio_to_irq(gpios[i].gpio),
 279                                               gpio_handler,
 280                                               IRQF_TRIGGER_RISING |
 281                                               IRQF_TRIGGER_FALLING,
 282                                               jack->codec->dev->driver->name,
 283                                               &gpios[i]);
 284                 if (ret)
 285                         goto err;
 286
 287 #ifdef CONFIG_GPIO_SYSFS
 288                 /* Expose GPIO value over sysfs for diagnostic purposes */
 289                 gpio_export(gpios[i].gpio, false);
 290 #endif
 291
 292                 /* Update initial jack status */
 293                 snd_soc_jack_gpio_detect(&gpios[i]);
 294         }
 295
 296         return 0;
 297
 298 err:
 299         gpio_free(gpios[i].gpio);
 300 undo:
 301         snd_soc_jack_free_gpios(jack, i, gpios);
 302
 303         return ret;
 304 }
 305 EXPORT_SYMBOL_GPL(snd_soc_jack_add_gpios);
 306
 307 /**
 308  * snd_soc_jack_free_gpios - Release GPIO pins' resources of an ASoC jack
 309  *
 310  * @jack:  ASoC jack
 311  * @count: number of pins
 312  * @gpios: array of gpio pins
 313  *
 314  * Release gpio and irq resources for gpio pins associated with an ASoC jack.
 315  */
 316 void snd_soc_jack_free_gpios(struct snd_soc_jack *jack, int count,
 317                         struct snd_soc_jack_gpio *gpios)
 318 {
 319         int i;
 320
 321         for (i = 0; i < count; i++) {
 322 #ifdef CONFIG_GPIO_SYSFS
 323                 gpio_unexport(gpios[i].gpio);
 324 #endif
 325                 free_irq(gpio_to_irq(gpios[i].gpio), &gpios[i]);
 326                 cancel_delayed_work_sync(&gpios[i].work);
 327                 gpio_free(gpios[i].gpio);
 328                 gpios[i].jack = NULL;
 329         }
 330 }
 331 EXPORT_SYMBOL_GPL(snd_soc_jack_free_gpios);
 332 #endif  /* CONFIG_GPIOLIB */