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 <sound/jack.h>
  24 #include <sound/core.h>
  25
  26 static int snd_jack_dev_free(struct snd_device *device)
  27 {
  28         struct snd_jack *jack = device->device_data;
  29
  30         /* If the input device is registered with the input subsystem
  31          * then we need to use a different deallocator. */
  32         if (jack->registered)
  33                 input_unregister_device(jack->input_dev);
  34         else
  35                 input_free_device(jack->input_dev);
  36
  37         kfree(jack);
  38
  39         return 0;
  40 }
  41
  42 static int snd_jack_dev_register(struct snd_device *device)
  43 {
  44         struct snd_jack *jack = device->device_data;
  45         struct snd_card *card = device->card;
  46         int err;
  47
  48         snprintf(jack->name, sizeof(jack->name), "%s %s",
  49                  card->longname, jack->id);
  50         jack->input_dev->name = jack->name;
  51
  52         /* Default to the sound card device. */
  53         if (!jack->input_dev->dev.parent)
  54                 jack->input_dev->dev.parent = card->dev;
  55
  56         err = input_register_device(jack->input_dev);
  57         if (err == 0)
  58                 jack->registered = 1;
  59
  60         return err;
  61 }
  62
  63 /**
  64  * snd_jack_new - Create a new jack
  65  * @card:  the card instance
  66  * @id:    an identifying string for this jack
  67  * @type:  a bitmask of enum snd_jack_type values that can be detected by
  68  *         this jack
  69  * @jjack: Used to provide the allocated jack object to the caller.
  70  *
  71  * Creates a new jack object.
  72  *
  73  * Returns zero if successful, or a negative error code on failure.
  74  * On success jjack will be initialised.
  75  */
  76 int snd_jack_new(struct snd_card *card, const char *id, int type,
  77                  struct snd_jack **jjack)
  78 {
  79         struct snd_jack *jack;
  80         int err;
  81         static struct snd_device_ops ops = {
  82                 .dev_free = snd_jack_dev_free,
  83                 .dev_register = snd_jack_dev_register,
  84         };
  85
  86         jack = kzalloc(sizeof(struct snd_jack), GFP_KERNEL);
  87         if (jack == NULL)
  88                 return -ENOMEM;
  89
  90         jack->id = id;
  91
  92         jack->input_dev = input_allocate_device();
  93         if (jack->input_dev == NULL) {
  94                 err = -ENOMEM;
  95                 goto fail_input;
  96         }
  97
  98         jack->input_dev->phys = "ALSA";
  99
 100         jack->type = type;
 101
 102         if (type & SND_JACK_HEADPHONE)
 103                 input_set_capability(jack->input_dev, EV_SW,
 104                                      SW_HEADPHONE_INSERT);
 105         if (type & SND_JACK_MICROPHONE)
 106                 input_set_capability(jack->input_dev, EV_SW,
 107                                      SW_MICROPHONE_INSERT);
 108
 109         err = snd_device_new(card, SNDRV_DEV_JACK, jack, &ops);
 110         if (err < 0)
 111                 goto fail_input;
 112
 113         *jjack = jack;
 114
 115         return 0;
 116
 117 fail_input:
 118         input_free_device(jack->input_dev);
 119         kfree(jack);
 120         return err;
 121 }
 122 EXPORT_SYMBOL(snd_jack_new);
 123
 124 /**
 125  * snd_jack_set_parent - Set the parent device for a jack
 126  *
 127  * @jack:   The jack to configure
 128  * @parent: The device to set as parent for the jack.
 129  *
 130  * Set the parent for the jack input device in the device tree.  This
 131  * function is only valid prior to registration of the jack.  If no
 132  * parent is configured then the parent device will be the sound card.
 133  */
 134 void snd_jack_set_parent(struct snd_jack *jack, struct device *parent)
 135 {
 136         WARN_ON(jack->registered);
 137
 138         jack->input_dev->dev.parent = parent;
 139 }
 140 EXPORT_SYMBOL(snd_jack_set_parent);
 141
 142 /**
 143  * snd_jack_report - Report the current status of a jack
 144  *
 145  * @jack:   The jack to report status for
 146  * @status: The current status of the jack
 147  */
 148 void snd_jack_report(struct snd_jack *jack, int status)
 149 {
 150         if (!jack)
 151                 return;
 152
 153         if (jack->type & SND_JACK_HEADPHONE)
 154                 input_report_switch(jack->input_dev, SW_HEADPHONE_INSERT,
 155                                     status & SND_JACK_HEADPHONE);
 156         if (jack->type & SND_JACK_MICROPHONE)
 157                 input_report_switch(jack->input_dev, SW_MICROPHONE_INSERT,
 158                                     status & SND_JACK_MICROPHONE);
 159
 160         input_sync(jack->input_dev);
 161 }
 162 EXPORT_SYMBOL(snd_jack_report);
 163
 164 MODULE_AUTHOR("Mark Brown <broonie@opensource.wolfsonmicro.com>");
 165 MODULE_DESCRIPTION("Jack detection support for ALSA");
 166 MODULE_LICENSE("GPL");