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 <linux/module.h>
  25 #include <sound/jack.h>
  26 #include <sound/core.h>
  27
  28 static int jack_switch_types[] = {
  29         SW_HEADPHONE_INSERT,
  30         SW_MICROPHONE_INSERT,
  31         SW_LINEOUT_INSERT,
  32         SW_JACK_PHYSICAL_INSERT,
  33         SW_VIDEOOUT_INSERT,
  34 };
  35
  36 static int snd_jack_dev_free(struct snd_device *device)
  37 {
  38         struct snd_jack *jack = device->device_data;
  39
  40         if (jack->private_free)
  41                 jack->private_free(jack);
  42
  43         /* If the input device is registered with the input subsystem
  44          * then we need to use a different deallocator. */
  45         if (jack->registered)
  46                 input_unregister_device(jack->input_dev);
  47         else
  48                 input_free_device(jack->input_dev);
  49
  50         kfree(jack->id);
  51         kfree(jack);
  52
  53         return 0;
  54 }
  55
  56 static int snd_jack_dev_register(struct snd_device *device)
  57 {
  58         struct snd_jack *jack = device->device_data;
  59         struct snd_card *card = device->card;
  60         int err, i;
  61
  62         snprintf(jack->name, sizeof(jack->name), "%s %s",
  63                  card->shortname, jack->id);
  64         jack->input_dev->name = jack->name;
  65
  66         /* Default to the sound card device. */
  67         if (!jack->input_dev->dev.parent)
  68                 jack->input_dev->dev.parent = snd_card_get_device_link(card);
  69
  70         /* Add capabilities for any keys that are enabled */
  71         for (i = 0; i < ARRAY_SIZE(jack->key); i++) {
  72                 int testbit = SND_JACK_BTN_0 >> i;
  73
  74                 if (!(jack->type & testbit))
  75                         continue;
  76
  77                 if (!jack->key[i])
  78                         jack->key[i] = BTN_0 + i;
  79
  80                 input_set_capability(jack->input_dev, EV_KEY, jack->key[i]);
  81         }
  82
  83         err = input_register_device(jack->input_dev);
  84         if (err == 0)
  85                 jack->registered = 1;
  86
  87         return err;
  88 }
  89
  90 /**
  91  * snd_jack_new - Create a new jack
  92  * @card:  the card instance
  93  * @id:    an identifying string for this jack
  94  * @type:  a bitmask of enum snd_jack_type values that can be detected by
  95  *         this jack
  96  * @jjack: Used to provide the allocated jack object to the caller.
  97  *
  98  * Creates a new jack object.
  99  *
 100  * Returns zero if successful, or a negative error code on failure.
 101  * On success jjack will be initialised.
 102  */
 103 int snd_jack_new(struct snd_card *card, const char *id, int type,
 104                  struct snd_jack **jjack)
 105 {
 106         struct snd_jack *jack;
 107         int err;
 108         int i;
 109         static struct snd_device_ops ops = {
 110                 .dev_free = snd_jack_dev_free,
 111                 .dev_register = snd_jack_dev_register,
 112         };
 113
 114         jack = kzalloc(sizeof(struct snd_jack), GFP_KERNEL);
 115         if (jack == NULL)
 116                 return -ENOMEM;
 117
 118         jack->id = kstrdup(id, GFP_KERNEL);
 119
 120         jack->input_dev = input_allocate_device();
 121         if (jack->input_dev == NULL) {
 122                 err = -ENOMEM;
 123                 goto fail_input;
 124         }
 125
 126         jack->input_dev->phys = "ALSA";
 127
 128         jack->type = type;
 129
 130         for (i = 0; i < ARRAY_SIZE(jack_switch_types); i++)
 131                 if (type & (1 << i))
 132                         input_set_capability(jack->input_dev, EV_SW,
 133                                              jack_switch_types[i]);
 134
 135         err = snd_device_new(card, SNDRV_DEV_JACK, jack, &ops);
 136         if (err < 0)
 137                 goto fail_input;
 138
 139         *jjack = jack;
 140
 141         return 0;
 142
 143 fail_input:
 144         input_free_device(jack->input_dev);
 145         kfree(jack->id);
 146         kfree(jack);
 147         return err;
 148 }
 149 EXPORT_SYMBOL(snd_jack_new);
 150
 151 /**
 152  * snd_jack_set_parent - Set the parent device for a jack
 153  *
 154  * @jack:   The jack to configure
 155  * @parent: The device to set as parent for the jack.
 156  *
 157  * Set the parent for the jack input device in the device tree.  This
 158  * function is only valid prior to registration of the jack.  If no
 159  * parent is configured then the parent device will be the sound card.
 160  */
 161 void snd_jack_set_parent(struct snd_jack *jack, struct device *parent)
 162 {
 163         WARN_ON(jack->registered);
 164
 165         jack->input_dev->dev.parent = parent;
 166 }
 167 EXPORT_SYMBOL(snd_jack_set_parent);
 168
 169 /**
 170  * snd_jack_set_key - Set a key mapping on a jack
 171  *
 172  * @jack:    The jack to configure
 173  * @type:    Jack report type for this key
 174  * @keytype: Input layer key type to be reported
 175  *
 176  * Map a SND_JACK_BTN_ button type to an input layer key, allowing
 177  * reporting of keys on accessories via the jack abstraction.  If no
 178  * mapping is provided but keys are enabled in the jack type then
 179  * BTN_n numeric buttons will be reported.
 180  *
 181  * Note that this is intended to be use by simple devices with small
 182  * numbers of keys that can be reported.  It is also possible to
 183  * access the input device directly - devices with complex input
 184  * capabilities on accessories should consider doing this rather than
 185  * using this abstraction.
 186  *
 187  * This function may only be called prior to registration of the jack.
 188  */
 189 int snd_jack_set_key(struct snd_jack *jack, enum snd_jack_types type,
 190                      int keytype)
 191 {
 192         int key = fls(SND_JACK_BTN_0) - fls(type);
 193
 194         WARN_ON(jack->registered);
 195
 196         if (!keytype || key >= ARRAY_SIZE(jack->key))
 197                 return -EINVAL;
 198
 199         jack->type |= type;
 200         jack->key[key] = keytype;
 201
 202         return 0;
 203 }
 204 EXPORT_SYMBOL(snd_jack_set_key);
 205
 206 /**
 207  * snd_jack_report - Report the current status of a jack
 208  *
 209  * @jack:   The jack to report status for
 210  * @status: The current status of the jack
 211  */
 212 void snd_jack_report(struct snd_jack *jack, int status)
 213 {
 214         int i;
 215
 216         if (!jack)
 217                 return;
 218
 219         for (i = 0; i < ARRAY_SIZE(jack->key); i++) {
 220                 int testbit = SND_JACK_BTN_0 >> i;
 221
 222                 if (jack->type & testbit)
 223                         input_report_key(jack->input_dev, jack->key[i],
 224                                          status & testbit);
 225         }
 226
 227         for (i = 0; i < ARRAY_SIZE(jack_switch_types); i++) {
 228                 int testbit = 1 << i;
 229                 if (jack->type & testbit)
 230                         input_report_switch(jack->input_dev,
 231                                             jack_switch_types[i],
 232                                             status & testbit);
 233         }
 234
 235         input_sync(jack->input_dev);
 236 }
 237 EXPORT_SYMBOL(snd_jack_report);
 238
 239 MODULE_AUTHOR("Mark Brown <broonie@opensource.wolfsonmicro.com>");
 240 MODULE_DESCRIPTION("Jack detection support for ALSA");
 241 MODULE_LICENSE("GPL");