sound/core/jack.c

   1 /*
   2  *  Jack abstraction layer
   3  *
   4  *  Copyright 2008 Wolfson Microelectronics
   5  *
   6  *   This program is free software; you can redistribute it and/or modify
   7  *   it under the terms of the GNU General Public License as published by
   8  *   the Free Software Foundation; either version 2 of the License, or
   9  *   (at your option) any later version.
  10  *
  11  *   This program is distributed in the hope that it will be useful,
  12  *   but WITHOUT ANY WARRANTY; without even the implied warranty of
  13  *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14  *   GNU General Public License for more details.
  15  *
  16  *   You should have received a copy of the GNU General Public License
  17  *   along with this program; if not, write to the Free Software
  18  *   Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307 USA
  19  *
  20  */
  21
  22 #include <linux/input.h>
  23 #include <linux/slab.h>
  24 #include <sound/jack.h>
  25 #include <sound/core.h>
  26
  27 static int jack_types[] = {
  28         SW_HEADPHONE_INSERT,
  29         SW_MICROPHONE_INSERT,
  30         SW_LINEOUT_INSERT,
  31         SW_JACK_PHYSICAL_INSERT,
  32         SW_VIDEOOUT_INSERT,
  33 };
  34
  35 static int snd_jack_dev_free(struct snd_device *device)
  36 {
  37         struct snd_jack *jack = device->device_data;
  38
  39         if (jack->private_free)
  40                 jack->private_free(jack);
  41
  42         /* If the input device is registered with the input subsystem
  43          * then we need to use a different deallocator. */
  44         if (jack->registered)
  45                 input_unregister_device(jack->input_dev);
  46         else
  47                 input_free_device(jack->input_dev);
  48
  49         kfree(jack->id);
  50         kfree(jack);
  51
  52         return 0;
  53 }
  54
  55 static int snd_jack_dev_register(struct snd_device *device)
  56 {
  57         struct snd_jack *jack = device->device_data;
  58         struct snd_card *card = device->card;
  59         int err;
  60
  61         snprintf(jack->name, sizeof(jack->name), "%s %s",
  62                  card->shortname, jack->id);
  63         jack->input_dev->name = jack->name;
  64
  65         /* Default to the sound card device. */
  66         if (!jack->input_dev->dev.parent)
  67                 jack->input_dev->dev.parent = snd_card_get_device_link(card);
  68
  69         err = input_register_device(jack->input_dev);
  70         if (err == 0)
  71                 jack->registered = 1;
  72
  73         return err;
  74 }
  75
  76 /**
  77  * snd_jack_new - Create a new jack
  78  * @card:  the card instance
  79  * @id:    an identifying string for this jack
  80  * @type:  a bitmask of enum snd_jack_type values that can be detected by
  81  *         this jack
  82  * @jjack: Used to provide the allocated jack object to the caller.
  83  *
  84  * Creates a new jack object.
  85  *
  86  * Returns zero if successful, or a negative error code on failure.
  87  * On success jjack will be initialised.
  88  */
  89 int snd_jack_new(struct snd_card *card, const char *id, int type,
  90                  struct snd_jack **jjack)
  91 {
  92         struct snd_jack *jack;
  93         int err;
  94         int i;
  95         static struct snd_device_ops ops = {
  96                 .dev_free = snd_jack_dev_free,
  97                 .dev_register = snd_jack_dev_register,
  98         };
  99
 100         jack = kzalloc(sizeof(struct snd_jack), GFP_KERNEL);
 101         if (jack == NULL)
 102                 return -ENOMEM;
 103
 104         jack->id = kstrdup(id, GFP_KERNEL);
 105
 106         jack->input_dev = input_allocate_device();
 107         if (jack->input_dev == NULL) {
 108                 err = -ENOMEM;
 109                 goto fail_input;
 110         }
 111
 112         jack->input_dev->phys = "ALSA";
 113
 114         jack->type = type;
 115
 116         for (i = 0; i < ARRAY_SIZE(jack_types); i++)
 117                 if (type & (1 << i))
 118                         input_set_capability(jack->input_dev, EV_SW,
 119                                              jack_types[i]);
 120
 121         err = snd_device_new(card, SNDRV_DEV_JACK, jack, &ops);
 122         if (err < 0)
 123                 goto fail_input;
 124
 125         *jjack = jack;
 126
 127         return 0;
 128
 129 fail_input:
 130         input_free_device(jack->input_dev);
 131         kfree(jack);
 132         return err;
 133 }
 134 EXPORT_SYMBOL(snd_jack_new);
 135
 136 /**
 137  * snd_jack_set_parent - Set the parent device for a jack
 138  *
 139  * @jack:   The jack to configure
 140  * @parent: The device to set as parent for the jack.
 141  *
 142  * Set the parent for the jack input device in the device tree.  This
 143  * function is only valid prior to registration of the jack.  If no
 144  * parent is configured then the parent device will be the sound card.
 145  */
 146 void snd_jack_set_parent(struct snd_jack *jack, struct device *parent)
 147 {
 148         WARN_ON(jack->registered);
 149
 150         jack->input_dev->dev.parent = parent;
 151 }
 152 EXPORT_SYMBOL(snd_jack_set_parent);
 153
 154 /**
 155  * snd_jack_report - Report the current status of a jack
 156  *
 157  * @jack:   The jack to report status for
 158  * @status: The current status of the jack
 159  */
 160 void snd_jack_report(struct snd_jack *jack, int status)
 161 {
 162         int i;
 163
 164         if (!jack)
 165                 return;
 166
 167         for (i = 0; i < ARRAY_SIZE(jack_types); i++) {
 168                 int testbit = 1 << i;
 169                 if (jack->type & testbit)
 170                         input_report_switch(jack->input_dev, jack_types[i],
 171                                             status & testbit);
 172         }
 173
 174         input_sync(jack->input_dev);
 175 }
 176 EXPORT_SYMBOL(snd_jack_report);
 177
 178 MODULE_AUTHOR("Mark Brown <broonie@opensource.wolfsonmicro.com>");
 179 MODULE_DESCRIPTION("Jack detection support for ALSA");
 180 MODULE_LICENSE("GPL");