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 <sound/soc-dapm.h>
  17 #include <linux/gpio.h>
  18 #include <linux/interrupt.h>
  19 #include <linux/workqueue.h>
  20 #include <linux/delay.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_card *card, const char *id, int type,
  36                      struct snd_soc_jack *jack)
  37 {
  38         jack->card = card;
  39         INIT_LIST_HEAD(&jack->pins);
  40
  41         return snd_jack_new(card->codec->card, id, type, &jack->jack);
  42 }
  43 EXPORT_SYMBOL_GPL(snd_soc_jack_new);
  44
  45 /**
  46  * snd_soc_jack_report - Report the current status for a jack
  47  *
  48  * @jack:   the jack
  49  * @status: a bitmask of enum snd_jack_type values that are currently detected.
  50  * @mask:   a bitmask of enum snd_jack_type values that being reported.
  51  *
  52  * If configured using snd_soc_jack_add_pins() then the associated
  53  * DAPM pins will be enabled or disabled as appropriate and DAPM
  54  * synchronised.
  55  *
  56  * Note: This function uses mutexes and should be called from a
  57  * context which can sleep (such as a workqueue).
  58  */
  59 void snd_soc_jack_report(struct snd_soc_jack *jack, int status, int mask)
  60 {
  61         struct snd_soc_codec *codec;
  62         struct snd_soc_jack_pin *pin;
  63         int enable;
  64         int oldstatus;
  65
  66         if (!jack) {
  67                 WARN_ON_ONCE(!jack);
  68                 return;
  69         }
  70         codec = jack->card->codec;
  71
  72         mutex_lock(&codec->mutex);
  73
  74         oldstatus = jack->status;
  75
  76         jack->status &= ~mask;
  77         jack->status |= status & mask;
  78
  79         /* The DAPM sync is expensive enough to be worth skipping.
  80          * However, empty mask means pin synchronization is desired. */
  81         if (mask && (jack->status == oldstatus))
  82                 goto out;
  83
  84         list_for_each_entry(pin, &jack->pins, list) {
  85                 enable = pin->mask & jack->status;
  86
  87                 if (pin->invert)
  88                         enable = !enable;
  89
  90                 if (enable)
  91                         snd_soc_dapm_enable_pin(codec, pin->pin);
  92                 else
  93                         snd_soc_dapm_disable_pin(codec, pin->pin);
  94         }
  95
  96         snd_soc_dapm_sync(codec);
  97
  98         snd_jack_report(jack->jack, status);
  99
 100 out:
 101         mutex_unlock(&codec->mutex);
 102 }
 103 EXPORT_SYMBOL_GPL(snd_soc_jack_report);
 104
 105 /**
 106  * snd_soc_jack_add_pins - Associate DAPM pins with an ASoC jack
 107  *
 108  * @jack:  ASoC jack
 109  * @count: Number of pins
 110  * @pins:  Array of pins
 111  *
 112  * After this function has been called the DAPM pins specified in the
 113  * pins array will have their status updated to reflect the current
 114  * state of the jack whenever the jack status is updated.
 115  */
 116 int snd_soc_jack_add_pins(struct snd_soc_jack *jack, int count,
 117                           struct snd_soc_jack_pin *pins)
 118 {
 119         int i;
 120
 121         for (i = 0; i < count; i++) {
 122                 if (!pins[i].pin) {
 123                         printk(KERN_ERR "No name for pin %d\n", i);
 124                         return -EINVAL;
 125                 }
 126                 if (!pins[i].mask) {
 127                         printk(KERN_ERR "No mask for pin %d (%s)\n", i,
 128                                pins[i].pin);
 129                         return -EINVAL;
 130                 }
 131
 132                 INIT_LIST_HEAD(&pins[i].list);
 133                 list_add(&(pins[i].list), &jack->pins);
 134         }
 135
 136         /* Update to reflect the last reported status; canned jack
 137          * implementations are likely to set their state before the
 138          * card has an opportunity to associate pins.
 139          */
 140         snd_soc_jack_report(jack, 0, 0);
 141
 142         return 0;
 143 }
 144 EXPORT_SYMBOL_GPL(snd_soc_jack_add_pins);
 145
 146 #ifdef CONFIG_GPIOLIB
 147 /* gpio detect */
 148 static void snd_soc_jack_gpio_detect(struct snd_soc_jack_gpio *gpio)
 149 {
 150         struct snd_soc_jack *jack = gpio->jack;
 151         int enable;
 152         int report;
 153
 154         if (gpio->debounce_time > 0)
 155                 mdelay(gpio->debounce_time);
 156
 157         enable = gpio_get_value(gpio->gpio);
 158         if (gpio->invert)
 159                 enable = !enable;
 160
 161         if (enable)
 162                 report = gpio->report;
 163         else
 164                 report = 0;
 165
 166         if (gpio->jack_status_check)
 167                 report = gpio->jack_status_check();
 168
 169         snd_soc_jack_report(jack, report, gpio->report);
 170 }
 171
 172 /* irq handler for gpio pin */
 173 static irqreturn_t gpio_handler(int irq, void *data)
 174 {
 175         struct snd_soc_jack_gpio *gpio = data;
 176
 177         schedule_work(&gpio->work);
 178
 179         return IRQ_HANDLED;
 180 }
 181
 182 /* gpio work */
 183 static void gpio_work(struct work_struct *work)
 184 {
 185         struct snd_soc_jack_gpio *gpio;
 186
 187         gpio = container_of(work, struct snd_soc_jack_gpio, work);
 188         snd_soc_jack_gpio_detect(gpio);
 189 }
 190
 191 /**
 192  * snd_soc_jack_add_gpios - Associate GPIO pins with an ASoC jack
 193  *
 194  * @jack:  ASoC jack
 195  * @count: number of pins
 196  * @gpios: array of gpio pins
 197  *
 198  * This function will request gpio, set data direction and request irq
 199  * for each gpio in the array.
 200  */
 201 int snd_soc_jack_add_gpios(struct snd_soc_jack *jack, int count,
 202                         struct snd_soc_jack_gpio *gpios)
 203 {
 204         int i, ret;
 205
 206         for (i = 0; i < count; i++) {
 207                 if (!gpio_is_valid(gpios[i].gpio)) {
 208                         printk(KERN_ERR "Invalid gpio %d\n",
 209                                 gpios[i].gpio);
 210                         ret = -EINVAL;
 211                         goto undo;
 212                 }
 213                 if (!gpios[i].name) {
 214                         printk(KERN_ERR "No name for gpio %d\n",
 215                                 gpios[i].gpio);
 216                         ret = -EINVAL;
 217                         goto undo;
 218                 }
 219
 220                 ret = gpio_request(gpios[i].gpio, gpios[i].name);
 221                 if (ret)
 222                         goto undo;
 223
 224                 ret = gpio_direction_input(gpios[i].gpio);
 225                 if (ret)
 226                         goto err;
 227
 228                 INIT_WORK(&gpios[i].work, gpio_work);
 229                 gpios[i].jack = jack;
 230
 231                 ret = request_irq(gpio_to_irq(gpios[i].gpio),
 232                                 gpio_handler,
 233                                 IRQF_TRIGGER_RISING | IRQF_TRIGGER_FALLING,
 234                                 jack->card->dev->driver->name,
 235                                 &gpios[i]);
 236                 if (ret)
 237                         goto err;
 238
 239 #ifdef CONFIG_GPIO_SYSFS
 240                 /* Expose GPIO value over sysfs for diagnostic purposes */
 241                 gpio_export(gpios[i].gpio, false);
 242 #endif
 243
 244                 /* Update initial jack status */
 245                 snd_soc_jack_gpio_detect(&gpios[i]);
 246         }
 247
 248         return 0;
 249
 250 err:
 251         gpio_free(gpios[i].gpio);
 252 undo:
 253         snd_soc_jack_free_gpios(jack, i, gpios);
 254
 255         return ret;
 256 }
 257 EXPORT_SYMBOL_GPL(snd_soc_jack_add_gpios);
 258
 259 /**
 260  * snd_soc_jack_free_gpios - Release GPIO pins' resources of an ASoC jack
 261  *
 262  * @jack:  ASoC jack
 263  * @count: number of pins
 264  * @gpios: array of gpio pins
 265  *
 266  * Release gpio and irq resources for gpio pins associated with an ASoC jack.
 267  */
 268 void snd_soc_jack_free_gpios(struct snd_soc_jack *jack, int count,
 269                         struct snd_soc_jack_gpio *gpios)
 270 {
 271         int i;
 272
 273         for (i = 0; i < count; i++) {
 274 #ifdef CONFIG_GPIO_SYSFS
 275                 gpio_unexport(gpios[i].gpio);
 276 #endif
 277                 free_irq(gpio_to_irq(gpios[i].gpio), &gpios[i]);
 278                 gpio_free(gpios[i].gpio);
 279                 gpios[i].jack = NULL;
 280         }
 281 }
 282 EXPORT_SYMBOL_GPL(snd_soc_jack_free_gpios);
 283 #endif  /* CONFIG_GPIOLIB */