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