xref: /openbmc/linux/sound/core/jack.c (revision a09d2831)
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 jack_types[] = {
27 	SW_HEADPHONE_INSERT,
28 	SW_MICROPHONE_INSERT,
29 	SW_LINEOUT_INSERT,
30 	SW_JACK_PHYSICAL_INSERT,
31 	SW_VIDEOOUT_INSERT,
32 };
33 
34 static int snd_jack_dev_free(struct snd_device *device)
35 {
36 	struct snd_jack *jack = device->device_data;
37 
38 	if (jack->private_free)
39 		jack->private_free(jack);
40 
41 	/* If the input device is registered with the input subsystem
42 	 * then we need to use a different deallocator. */
43 	if (jack->registered)
44 		input_unregister_device(jack->input_dev);
45 	else
46 		input_free_device(jack->input_dev);
47 
48 	kfree(jack->id);
49 	kfree(jack);
50 
51 	return 0;
52 }
53 
54 static int snd_jack_dev_register(struct snd_device *device)
55 {
56 	struct snd_jack *jack = device->device_data;
57 	struct snd_card *card = device->card;
58 	int err;
59 
60 	snprintf(jack->name, sizeof(jack->name), "%s %s",
61 		 card->shortname, jack->id);
62 	jack->input_dev->name = jack->name;
63 
64 	/* Default to the sound card device. */
65 	if (!jack->input_dev->dev.parent)
66 		jack->input_dev->dev.parent = snd_card_get_device_link(card);
67 
68 	err = input_register_device(jack->input_dev);
69 	if (err == 0)
70 		jack->registered = 1;
71 
72 	return err;
73 }
74 
75 /**
76  * snd_jack_new - Create a new jack
77  * @card:  the card instance
78  * @id:    an identifying string for this jack
79  * @type:  a bitmask of enum snd_jack_type values that can be detected by
80  *         this jack
81  * @jjack: Used to provide the allocated jack object to the caller.
82  *
83  * Creates a new jack object.
84  *
85  * Returns zero if successful, or a negative error code on failure.
86  * On success jjack will be initialised.
87  */
88 int snd_jack_new(struct snd_card *card, const char *id, int type,
89 		 struct snd_jack **jjack)
90 {
91 	struct snd_jack *jack;
92 	int err;
93 	int i;
94 	static struct snd_device_ops ops = {
95 		.dev_free = snd_jack_dev_free,
96 		.dev_register = snd_jack_dev_register,
97 	};
98 
99 	jack = kzalloc(sizeof(struct snd_jack), GFP_KERNEL);
100 	if (jack == NULL)
101 		return -ENOMEM;
102 
103 	jack->id = kstrdup(id, GFP_KERNEL);
104 
105 	jack->input_dev = input_allocate_device();
106 	if (jack->input_dev == NULL) {
107 		err = -ENOMEM;
108 		goto fail_input;
109 	}
110 
111 	jack->input_dev->phys = "ALSA";
112 
113 	jack->type = type;
114 
115 	for (i = 0; i < ARRAY_SIZE(jack_types); i++)
116 		if (type & (1 << i))
117 			input_set_capability(jack->input_dev, EV_SW,
118 					     jack_types[i]);
119 
120 	err = snd_device_new(card, SNDRV_DEV_JACK, jack, &ops);
121 	if (err < 0)
122 		goto fail_input;
123 
124 	*jjack = jack;
125 
126 	return 0;
127 
128 fail_input:
129 	input_free_device(jack->input_dev);
130 	kfree(jack);
131 	return err;
132 }
133 EXPORT_SYMBOL(snd_jack_new);
134 
135 /**
136  * snd_jack_set_parent - Set the parent device for a jack
137  *
138  * @jack:   The jack to configure
139  * @parent: The device to set as parent for the jack.
140  *
141  * Set the parent for the jack input device in the device tree.  This
142  * function is only valid prior to registration of the jack.  If no
143  * parent is configured then the parent device will be the sound card.
144  */
145 void snd_jack_set_parent(struct snd_jack *jack, struct device *parent)
146 {
147 	WARN_ON(jack->registered);
148 
149 	jack->input_dev->dev.parent = parent;
150 }
151 EXPORT_SYMBOL(snd_jack_set_parent);
152 
153 /**
154  * snd_jack_report - Report the current status of a jack
155  *
156  * @jack:   The jack to report status for
157  * @status: The current status of the jack
158  */
159 void snd_jack_report(struct snd_jack *jack, int status)
160 {
161 	int i;
162 
163 	if (!jack)
164 		return;
165 
166 	for (i = 0; i < ARRAY_SIZE(jack_types); i++) {
167 		int testbit = 1 << i;
168 		if (jack->type & testbit)
169 			input_report_switch(jack->input_dev, jack_types[i],
170 					    status & testbit);
171 	}
172 
173 	input_sync(jack->input_dev);
174 }
175 EXPORT_SYMBOL(snd_jack_report);
176 
177 MODULE_AUTHOR("Mark Brown <broonie@opensource.wolfsonmicro.com>");
178 MODULE_DESCRIPTION("Jack detection support for ALSA");
179 MODULE_LICENSE("GPL");
180