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 = jack->card->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
  71         mutex_lock(&codec->mutex);
  72
  73         oldstatus = jack->status;
  74
  75         jack->status &= ~mask;
  76         jack->status |= status;
  77
  78         /* The DAPM sync is expensive enough to be worth skipping */
  79         if (jack->status == oldstatus)
  80                 goto out;
  81
  82         list_for_each_entry(pin, &jack->pins, list) {
  83                 enable = pin->mask & status;
  84
  85                 if (pin->invert)
  86                         enable = !enable;
  87
  88                 if (enable)
  89                         snd_soc_dapm_enable_pin(codec, pin->pin);
  90                 else
  91                         snd_soc_dapm_disable_pin(codec, pin->pin);
  92         }
  93
  94         snd_soc_dapm_sync(codec);
  95
  96         snd_jack_report(jack->jack, status);
  97
  98 out:
  99         mutex_unlock(&codec->mutex);
 100 }
 101 EXPORT_SYMBOL_GPL(snd_soc_jack_report);
 102
 103 /**
 104  * snd_soc_jack_add_pins - Associate DAPM pins with an ASoC jack
 105  *
 106  * @jack:  ASoC jack
 107  * @count: Number of pins
 108  * @pins:  Array of pins
 109  *
 110  * After this function has been called the DAPM pins specified in the
 111  * pins array will have their status updated to reflect the current
 112  * state of the jack whenever the jack status is updated.
 113  */
 114 int snd_soc_jack_add_pins(struct snd_soc_jack *jack, int count,
 115                           struct snd_soc_jack_pin *pins)
 116 {
 117         int i;
 118
 119         for (i = 0; i < count; i++) {
 120                 if (!pins[i].pin) {
 121                         printk(KERN_ERR "No name for pin %d\n", i);
 122                         return -EINVAL;
 123                 }
 124                 if (!pins[i].mask) {
 125                         printk(KERN_ERR "No mask for pin %d (%s)\n", i,
 126                                pins[i].pin);
 127                         return -EINVAL;
 128                 }
 129
 130                 INIT_LIST_HEAD(&pins[i].list);
 131                 list_add(&(pins[i].list), &jack->pins);
 132         }
 133
 134         /* Update to reflect the last reported status; canned jack
 135          * implementations are likely to set their state before the
 136          * card has an opportunity to associate pins.
 137          */
 138         snd_soc_jack_report(jack, 0, 0);
 139
 140         return 0;
 141 }
 142 EXPORT_SYMBOL_GPL(snd_soc_jack_add_pins);
 143
 144 #ifdef CONFIG_GPIOLIB
 145 /* gpio detect */
 146 static void snd_soc_jack_gpio_detect(struct snd_soc_jack_gpio *gpio)
 147 {
 148         struct snd_soc_jack *jack = gpio->jack;
 149         int enable;
 150         int report;
 151
 152         if (gpio->debounce_time > 0)
 153                 mdelay(gpio->debounce_time);
 154
 155         enable = gpio_get_value(gpio->gpio);
 156         if (gpio->invert)
 157                 enable = !enable;
 158
 159         if (enable)
 160                 report = gpio->report;
 161         else
 162                 report = 0;
 163
 164         snd_soc_jack_report(jack, report, gpio->report);
 165 }
 166
 167 /* irq handler for gpio pin */
 168 static irqreturn_t gpio_handler(int irq, void *data)
 169 {
 170         struct snd_soc_jack_gpio *gpio = data;
 171
 172         schedule_work(&gpio->work);
 173
 174         return IRQ_HANDLED;
 175 }
 176
 177 /* gpio work */
 178 static void gpio_work(struct work_struct *work)
 179 {
 180         struct snd_soc_jack_gpio *gpio;
 181
 182         gpio = container_of(work, struct snd_soc_jack_gpio, work);
 183         snd_soc_jack_gpio_detect(gpio);
 184 }
 185
 186 /**
 187  * snd_soc_jack_add_gpios - Associate GPIO pins with an ASoC jack
 188  *
 189  * @jack:  ASoC jack
 190  * @count: number of pins
 191  * @gpios: array of gpio pins
 192  *
 193  * This function will request gpio, set data direction and request irq
 194  * for each gpio in the array.
 195  */
 196 int snd_soc_jack_add_gpios(struct snd_soc_jack *jack, int count,
 197                         struct snd_soc_jack_gpio *gpios)
 198 {
 199         int i, ret;
 200
 201         for (i = 0; i < count; i++) {
 202                 if (!gpio_is_valid(gpios[i].gpio)) {
 203                         printk(KERN_ERR "Invalid gpio %d\n",
 204                                 gpios[i].gpio);
 205                         ret = -EINVAL;
 206                         goto undo;
 207                 }
 208                 if (!gpios[i].name) {
 209                         printk(KERN_ERR "No name for gpio %d\n",
 210                                 gpios[i].gpio);
 211                         ret = -EINVAL;
 212                         goto undo;
 213                 }
 214
 215                 ret = gpio_request(gpios[i].gpio, gpios[i].name);
 216                 if (ret)
 217                         goto undo;
 218
 219                 ret = gpio_direction_input(gpios[i].gpio);
 220                 if (ret)
 221                         goto err;
 222
 223                 ret = request_irq(gpio_to_irq(gpios[i].gpio),
 224                                 gpio_handler,
 225                                 IRQF_TRIGGER_RISING | IRQF_TRIGGER_FALLING,
 226                                 jack->card->dev->driver->name,
 227                                 &gpios[i]);
 228                 if (ret)
 229                         goto err;
 230
 231                 INIT_WORK(&gpios[i].work, gpio_work);
 232                 gpios[i].jack = jack;
 233         }
 234
 235         return 0;
 236
 237 err:
 238         gpio_free(gpios[i].gpio);
 239 undo:
 240         snd_soc_jack_free_gpios(jack, i, gpios);
 241
 242         return ret;
 243 }
 244 EXPORT_SYMBOL_GPL(snd_soc_jack_add_gpios);
 245
 246 /**
 247  * snd_soc_jack_free_gpios - Release GPIO pins' resources of an ASoC jack
 248  *
 249  * @jack:  ASoC jack
 250  * @count: number of pins
 251  * @gpios: array of gpio pins
 252  *
 253  * Release gpio and irq resources for gpio pins associated with an ASoC jack.
 254  */
 255 void snd_soc_jack_free_gpios(struct snd_soc_jack *jack, int count,
 256                         struct snd_soc_jack_gpio *gpios)
 257 {
 258         int i;
 259
 260         for (i = 0; i < count; i++) {
 261                 free_irq(gpio_to_irq(gpios[i].gpio), &gpios[i]);
 262                 gpio_free(gpios[i].gpio);
 263                 gpios[i].jack = NULL;
 264         }
 265 }
 266 EXPORT_SYMBOL_GPL(snd_soc_jack_free_gpios);
 267 #endif  /* CONFIG_GPIOLIB */