xref: /linux/sound/core/jack.c (revision 4dc7ccf7e9d9bca1989b840be9e8e84911387cf2)
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");
181