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 & mask;
  77
  78         /* The DAPM sync is expensive enough to be worth skipping.
  79          * However, empty mask means pin synchronization is desired. */
  80         if (mask && (jack->status == oldstatus))
  81                 goto out;
  82
  83         list_for_each_entry(pin, &jack->pins, list) {
  84                 enable = pin->mask & jack->status;
  85
  86                 if (pin->invert)
  87                         enable = !enable;
  88
  89                 if (enable)
  90                         snd_soc_dapm_enable_pin(codec, pin->pin);
  91                 else
  92                         snd_soc_dapm_disable_pin(codec, pin->pin);
  93         }
  94
  95         snd_soc_dapm_sync(codec);
  96
  97         snd_jack_report(jack->jack, jack->status);
  98
  99 out:
 100         mutex_unlock(&codec->mutex);
 101 }
 102 EXPORT_SYMBOL_GPL(snd_soc_jack_report);
 103
 104 /**
 105  * snd_soc_jack_add_pins - Associate DAPM pins with an ASoC jack
 106  *
 107  * @jack:  ASoC jack
 108  * @count: Number of pins
 109  * @pins:  Array of pins
 110  *
 111  * After this function has been called the DAPM pins specified in the
 112  * pins array will have their status updated to reflect the current
 113  * state of the jack whenever the jack status is updated.
 114  */
 115 int snd_soc_jack_add_pins(struct snd_soc_jack *jack, int count,
 116                           struct snd_soc_jack_pin *pins)
 117 {
 118         int i;
 119
 120         for (i = 0; i < count; i++) {
 121                 if (!pins[i].pin) {
 122                         printk(KERN_ERR "No name for pin %d\n", i);
 123                         return -EINVAL;
 124                 }
 125                 if (!pins[i].mask) {
 126                         printk(KERN_ERR "No mask for pin %d (%s)\n", i,
 127                                pins[i].pin);
 128                         return -EINVAL;
 129                 }
 130
 131                 INIT_LIST_HEAD(&pins[i].list);
 132                 list_add(&(pins[i].list), &jack->pins);
 133         }
 134
 135         /* Update to reflect the last reported status; canned jack
 136          * implementations are likely to set their state before the
 137          * card has an opportunity to associate pins.
 138          */
 139         snd_soc_jack_report(jack, 0, 0);
 140
 141         return 0;
 142 }
 143 EXPORT_SYMBOL_GPL(snd_soc_jack_add_pins);
 144
 145 #ifdef CONFIG_GPIOLIB
 146 /* gpio detect */
 147 static void snd_soc_jack_gpio_detect(struct snd_soc_jack_gpio *gpio)
 148 {
 149         struct snd_soc_jack *jack = gpio->jack;
 150         int enable;
 151         int report;
 152
 153         if (gpio->debounce_time > 0)
 154                 mdelay(gpio->debounce_time);
 155
 156         enable = gpio_get_value(gpio->gpio);
 157         if (gpio->invert)
 158                 enable = !enable;
 159
 160         if (enable)
 161                 report = gpio->report;
 162         else
 163                 report = 0;
 164
 165         snd_soc_jack_report(jack, report, gpio->report);
 166 }
 167
 168 /* irq handler for gpio pin */
 169 static irqreturn_t gpio_handler(int irq, void *data)
 170 {
 171         struct snd_soc_jack_gpio *gpio = data;
 172
 173         schedule_work(&gpio->work);
 174
 175         return IRQ_HANDLED;
 176 }
 177
 178 /* gpio work */
 179 static void gpio_work(struct work_struct *work)
 180 {
 181         struct snd_soc_jack_gpio *gpio;
 182
 183         gpio = container_of(work, struct snd_soc_jack_gpio, work);
 184         snd_soc_jack_gpio_detect(gpio);
 185 }
 186
 187 /**
 188  * snd_soc_jack_add_gpios - Associate GPIO pins with an ASoC jack
 189  *
 190  * @jack:  ASoC jack
 191  * @count: number of pins
 192  * @gpios: array of gpio pins
 193  *
 194  * This function will request gpio, set data direction and request irq
 195  * for each gpio in the array.
 196  */
 197 int snd_soc_jack_add_gpios(struct snd_soc_jack *jack, int count,
 198                         struct snd_soc_jack_gpio *gpios)
 199 {
 200         int i, ret;
 201
 202         for (i = 0; i < count; i++) {
 203                 if (!gpio_is_valid(gpios[i].gpio)) {
 204                         printk(KERN_ERR "Invalid gpio %d\n",
 205                                 gpios[i].gpio);
 206                         ret = -EINVAL;
 207                         goto undo;
 208                 }
 209                 if (!gpios[i].name) {
 210                         printk(KERN_ERR "No name for gpio %d\n",
 211                                 gpios[i].gpio);
 212                         ret = -EINVAL;
 213                         goto undo;
 214                 }
 215
 216                 ret = gpio_request(gpios[i].gpio, gpios[i].name);
 217                 if (ret)
 218                         goto undo;
 219
 220                 ret = gpio_direction_input(gpios[i].gpio);
 221                 if (ret)
 222                         goto err;
 223
 224                 INIT_WORK(&gpios[i].work, gpio_work);
 225                 gpios[i].jack = jack;
 226
 227                 ret = request_irq(gpio_to_irq(gpios[i].gpio),
 228                                 gpio_handler,
 229                                 IRQF_TRIGGER_RISING | IRQF_TRIGGER_FALLING,
 230                                 jack->card->dev->driver->name,
 231                                 &gpios[i]);
 232                 if (ret)
 233                         goto err;
 234
 235 #ifdef CONFIG_GPIO_SYSFS
 236                 /* Expose GPIO value over sysfs for diagnostic purposes */
 237                 gpio_export(gpios[i].gpio, false);
 238 #endif
 239
 240                 /* Update initial jack status */
 241                 snd_soc_jack_gpio_detect(&gpios[i]);
 242         }
 243
 244         return 0;
 245
 246 err:
 247         gpio_free(gpios[i].gpio);
 248 undo:
 249         snd_soc_jack_free_gpios(jack, i, gpios);
 250
 251         return ret;
 252 }
 253 EXPORT_SYMBOL_GPL(snd_soc_jack_add_gpios);
 254
 255 /**
 256  * snd_soc_jack_free_gpios - Release GPIO pins' resources of an ASoC jack
 257  *
 258  * @jack:  ASoC jack
 259  * @count: number of pins
 260  * @gpios: array of gpio pins
 261  *
 262  * Release gpio and irq resources for gpio pins associated with an ASoC jack.
 263  */
 264 void snd_soc_jack_free_gpios(struct snd_soc_jack *jack, int count,
 265                         struct snd_soc_jack_gpio *gpios)
 266 {
 267         int i;
 268
 269         for (i = 0; i < count; i++) {
 270 #ifdef CONFIG_GPIO_SYSFS
 271                 gpio_unexport(gpios[i].gpio);
 272 #endif
 273                 free_irq(gpio_to_irq(gpios[i].gpio), &gpios[i]);
 274                 gpio_free(gpios[i].gpio);
 275                 gpios[i].jack = NULL;
 276         }
 277 }
 278 EXPORT_SYMBOL_GPL(snd_soc_jack_free_gpios);
 279 #endif  /* CONFIG_GPIOLIB */