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
28static int jack_switch_types[SND_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	SW_LINEIN_INSERT,
35};
36
37static int snd_jack_dev_disconnect(struct snd_device *device)
38{
39	struct snd_jack *jack = device->device_data;
40
41	if (!jack->input_dev)
42		return 0;
43
44	/* If the input device is registered with the input subsystem
45	 * then we need to use a different deallocator. */
46	if (jack->registered)
47		input_unregister_device(jack->input_dev);
48	else
49		input_free_device(jack->input_dev);
50	jack->input_dev = NULL;
51	return 0;
52}
53
54static int snd_jack_dev_free(struct snd_device *device)
55{
56	struct snd_jack *jack = device->device_data;
57
58	if (jack->private_free)
59		jack->private_free(jack);
60
61	snd_jack_dev_disconnect(device);
62
63	kfree(jack->id);
64	kfree(jack);
65
66	return 0;
67}
68
69static int snd_jack_dev_register(struct snd_device *device)
70{
71	struct snd_jack *jack = device->device_data;
72	struct snd_card *card = device->card;
73	int err, i;
74
75	snprintf(jack->name, sizeof(jack->name), "%s %s",
76		 card->shortname, jack->id);
77	jack->input_dev->name = jack->name;
78
79	/* Default to the sound card device. */
80	if (!jack->input_dev->dev.parent)
81		jack->input_dev->dev.parent = snd_card_get_device_link(card);
82
83	/* Add capabilities for any keys that are enabled */
84	for (i = 0; i < ARRAY_SIZE(jack->key); i++) {
85		int testbit = SND_JACK_BTN_0 >> i;
86
87		if (!(jack->type & testbit))
88			continue;
89
90		if (!jack->key[i])
91			jack->key[i] = BTN_0 + i;
92
93		input_set_capability(jack->input_dev, EV_KEY, jack->key[i]);
94	}
95
96	err = input_register_device(jack->input_dev);
97	if (err == 0)
98		jack->registered = 1;
99
100	return err;
101}
102
103/**
104 * snd_jack_new - Create a new jack
105 * @card:  the card instance
106 * @id:    an identifying string for this jack
107 * @type:  a bitmask of enum snd_jack_type values that can be detected by
108 *         this jack
109 * @jjack: Used to provide the allocated jack object to the caller.
110 *
111 * Creates a new jack object.
112 *
113 * Return: Zero if successful, or a negative error code on failure.
114 * On success @jjack will be initialised.
115 */
116int snd_jack_new(struct snd_card *card, const char *id, int type,
117		 struct snd_jack **jjack)
118{
119	struct snd_jack *jack;
120	int err;
121	int i;
122	static struct snd_device_ops ops = {
123		.dev_free = snd_jack_dev_free,
124		.dev_register = snd_jack_dev_register,
125		.dev_disconnect = snd_jack_dev_disconnect,
126	};
127
128	jack = kzalloc(sizeof(struct snd_jack), GFP_KERNEL);
129	if (jack == NULL)
130		return -ENOMEM;
131
132	jack->id = kstrdup(id, GFP_KERNEL);
133
134	jack->input_dev = input_allocate_device();
135	if (jack->input_dev == NULL) {
136		err = -ENOMEM;
137		goto fail_input;
138	}
139
140	jack->input_dev->phys = "ALSA";
141
142	jack->type = type;
143
144	for (i = 0; i < SND_JACK_SWITCH_TYPES; i++)
145		if (type & (1 << i))
146			input_set_capability(jack->input_dev, EV_SW,
147					     jack_switch_types[i]);
148
149	err = snd_device_new(card, SNDRV_DEV_JACK, jack, &ops);
150	if (err < 0)
151		goto fail_input;
152
153	*jjack = jack;
154
155	return 0;
156
157fail_input:
158	input_free_device(jack->input_dev);
159	kfree(jack->id);
160	kfree(jack);
161	return err;
162}
163EXPORT_SYMBOL(snd_jack_new);
164
165/**
166 * snd_jack_set_parent - Set the parent device for a jack
167 *
168 * @jack:   The jack to configure
169 * @parent: The device to set as parent for the jack.
170 *
171 * Set the parent for the jack devices in the device tree.  This
172 * function is only valid prior to registration of the jack.  If no
173 * parent is configured then the parent device will be the sound card.
174 */
175void snd_jack_set_parent(struct snd_jack *jack, struct device *parent)
176{
177	WARN_ON(jack->registered);
178
179	jack->input_dev->dev.parent = parent;
180}
181EXPORT_SYMBOL(snd_jack_set_parent);
182
183/**
184 * snd_jack_set_key - Set a key mapping on a jack
185 *
186 * @jack:    The jack to configure
187 * @type:    Jack report type for this key
188 * @keytype: Input layer key type to be reported
189 *
190 * Map a SND_JACK_BTN_ button type to an input layer key, allowing
191 * reporting of keys on accessories via the jack abstraction.  If no
192 * mapping is provided but keys are enabled in the jack type then
193 * BTN_n numeric buttons will be reported.
194 *
195 * If jacks are not reporting via the input API this call will have no
196 * effect.
197 *
198 * Note that this is intended to be use by simple devices with small
199 * numbers of keys that can be reported.  It is also possible to
200 * access the input device directly - devices with complex input
201 * capabilities on accessories should consider doing this rather than
202 * using this abstraction.
203 *
204 * This function may only be called prior to registration of the jack.
205 *
206 * Return: Zero if successful, or a negative error code on failure.
207 */
208int snd_jack_set_key(struct snd_jack *jack, enum snd_jack_types type,
209		     int keytype)
210{
211	int key = fls(SND_JACK_BTN_0) - fls(type);
212
213	WARN_ON(jack->registered);
214
215	if (!keytype || key >= ARRAY_SIZE(jack->key))
216		return -EINVAL;
217
218	jack->type |= type;
219	jack->key[key] = keytype;
220
221	return 0;
222}
223EXPORT_SYMBOL(snd_jack_set_key);
224
225/**
226 * snd_jack_report - Report the current status of a jack
227 *
228 * @jack:   The jack to report status for
229 * @status: The current status of the jack
230 */
231void snd_jack_report(struct snd_jack *jack, int status)
232{
233	int i;
234
235	if (!jack)
236		return;
237
238	for (i = 0; i < ARRAY_SIZE(jack->key); i++) {
239		int testbit = SND_JACK_BTN_0 >> i;
240
241		if (jack->type & testbit)
242			input_report_key(jack->input_dev, jack->key[i],
243					 status & testbit);
244	}
245
246	for (i = 0; i < ARRAY_SIZE(jack_switch_types); i++) {
247		int testbit = 1 << i;
248		if (jack->type & testbit)
249			input_report_switch(jack->input_dev,
250					    jack_switch_types[i],
251					    status & testbit);
252	}
253
254	input_sync(jack->input_dev);
255}
256EXPORT_SYMBOL(snd_jack_report);
257
258MODULE_AUTHOR("Mark Brown <broonie@opensource.wolfsonmicro.com>");
259MODULE_DESCRIPTION("Jack detection support for ALSA");
260MODULE_LICENSE("GPL");
261