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