xref: /openbmc/linux/sound/soc/soc-jack.c (revision 7dd65feb)
1 /*
2  * soc-jack.c  --  ALSA SoC jack handling
3  *
4  * Copyright 2008 Wolfson Microelectronics PLC.
5  *
6  * Author: Mark Brown <broonie@opensource.wolfsonmicro.com>
7  *
8  *  This program is free software; you can redistribute  it and/or modify it
9  *  under  the terms of  the GNU General  Public License as published by the
10  *  Free Software Foundation;  either version 2 of the  License, or (at your
11  *  option) any later version.
12  */
13 
14 #include <sound/jack.h>
15 #include <sound/soc.h>
16 #include <sound/soc-dapm.h>
17 #include <linux/gpio.h>
18 #include <linux/interrupt.h>
19 #include <linux/workqueue.h>
20 #include <linux/delay.h>
21 
22 /**
23  * snd_soc_jack_new - Create a new jack
24  * @card:  ASoC card
25  * @id:    an identifying string for this jack
26  * @type:  a bitmask of enum snd_jack_type values that can be detected by
27  *         this jack
28  * @jack:  structure to use for the jack
29  *
30  * Creates a new jack object.
31  *
32  * Returns zero if successful, or a negative error code on failure.
33  * On success jack will be initialised.
34  */
35 int snd_soc_jack_new(struct snd_soc_card *card, const char *id, int type,
36 		     struct snd_soc_jack *jack)
37 {
38 	jack->card = card;
39 	INIT_LIST_HEAD(&jack->pins);
40 
41 	return snd_jack_new(card->codec->card, id, type, &jack->jack);
42 }
43 EXPORT_SYMBOL_GPL(snd_soc_jack_new);
44 
45 /**
46  * snd_soc_jack_report - Report the current status for a jack
47  *
48  * @jack:   the jack
49  * @status: a bitmask of enum snd_jack_type values that are currently detected.
50  * @mask:   a bitmask of enum snd_jack_type values that being reported.
51  *
52  * If configured using snd_soc_jack_add_pins() then the associated
53  * DAPM pins will be enabled or disabled as appropriate and DAPM
54  * synchronised.
55  *
56  * Note: This function uses mutexes and should be called from a
57  * context which can sleep (such as a workqueue).
58  */
59 void snd_soc_jack_report(struct snd_soc_jack *jack, int status, int mask)
60 {
61 	struct snd_soc_codec *codec;
62 	struct snd_soc_jack_pin *pin;
63 	int enable;
64 	int oldstatus;
65 
66 	if (!jack) {
67 		WARN_ON_ONCE(!jack);
68 		return;
69 	}
70 	codec = jack->card->codec;
71 
72 	mutex_lock(&codec->mutex);
73 
74 	oldstatus = jack->status;
75 
76 	jack->status &= ~mask;
77 	jack->status |= status & mask;
78 
79 	/* The DAPM sync is expensive enough to be worth skipping.
80 	 * However, empty mask means pin synchronization is desired. */
81 	if (mask && (jack->status == oldstatus))
82 		goto out;
83 
84 	list_for_each_entry(pin, &jack->pins, list) {
85 		enable = pin->mask & jack->status;
86 
87 		if (pin->invert)
88 			enable = !enable;
89 
90 		if (enable)
91 			snd_soc_dapm_enable_pin(codec, pin->pin);
92 		else
93 			snd_soc_dapm_disable_pin(codec, pin->pin);
94 	}
95 
96 	snd_soc_dapm_sync(codec);
97 
98 	snd_jack_report(jack->jack, status);
99 
100 out:
101 	mutex_unlock(&codec->mutex);
102 }
103 EXPORT_SYMBOL_GPL(snd_soc_jack_report);
104 
105 /**
106  * snd_soc_jack_add_pins - Associate DAPM pins with an ASoC jack
107  *
108  * @jack:  ASoC jack
109  * @count: Number of pins
110  * @pins:  Array of pins
111  *
112  * After this function has been called the DAPM pins specified in the
113  * pins array will have their status updated to reflect the current
114  * state of the jack whenever the jack status is updated.
115  */
116 int snd_soc_jack_add_pins(struct snd_soc_jack *jack, int count,
117 			  struct snd_soc_jack_pin *pins)
118 {
119 	int i;
120 
121 	for (i = 0; i < count; i++) {
122 		if (!pins[i].pin) {
123 			printk(KERN_ERR "No name for pin %d\n", i);
124 			return -EINVAL;
125 		}
126 		if (!pins[i].mask) {
127 			printk(KERN_ERR "No mask for pin %d (%s)\n", i,
128 			       pins[i].pin);
129 			return -EINVAL;
130 		}
131 
132 		INIT_LIST_HEAD(&pins[i].list);
133 		list_add(&(pins[i].list), &jack->pins);
134 	}
135 
136 	/* Update to reflect the last reported status; canned jack
137 	 * implementations are likely to set their state before the
138 	 * card has an opportunity to associate pins.
139 	 */
140 	snd_soc_jack_report(jack, 0, 0);
141 
142 	return 0;
143 }
144 EXPORT_SYMBOL_GPL(snd_soc_jack_add_pins);
145 
146 #ifdef CONFIG_GPIOLIB
147 /* gpio detect */
148 static void snd_soc_jack_gpio_detect(struct snd_soc_jack_gpio *gpio)
149 {
150 	struct snd_soc_jack *jack = gpio->jack;
151 	int enable;
152 	int report;
153 
154 	if (gpio->debounce_time > 0)
155 		mdelay(gpio->debounce_time);
156 
157 	enable = gpio_get_value(gpio->gpio);
158 	if (gpio->invert)
159 		enable = !enable;
160 
161 	if (enable)
162 		report = gpio->report;
163 	else
164 		report = 0;
165 
166 	if (gpio->jack_status_check)
167 		report = gpio->jack_status_check();
168 
169 	snd_soc_jack_report(jack, report, gpio->report);
170 }
171 
172 /* irq handler for gpio pin */
173 static irqreturn_t gpio_handler(int irq, void *data)
174 {
175 	struct snd_soc_jack_gpio *gpio = data;
176 
177 	schedule_work(&gpio->work);
178 
179 	return IRQ_HANDLED;
180 }
181 
182 /* gpio work */
183 static void gpio_work(struct work_struct *work)
184 {
185 	struct snd_soc_jack_gpio *gpio;
186 
187 	gpio = container_of(work, struct snd_soc_jack_gpio, work);
188 	snd_soc_jack_gpio_detect(gpio);
189 }
190 
191 /**
192  * snd_soc_jack_add_gpios - Associate GPIO pins with an ASoC jack
193  *
194  * @jack:  ASoC jack
195  * @count: number of pins
196  * @gpios: array of gpio pins
197  *
198  * This function will request gpio, set data direction and request irq
199  * for each gpio in the array.
200  */
201 int snd_soc_jack_add_gpios(struct snd_soc_jack *jack, int count,
202 			struct snd_soc_jack_gpio *gpios)
203 {
204 	int i, ret;
205 
206 	for (i = 0; i < count; i++) {
207 		if (!gpio_is_valid(gpios[i].gpio)) {
208 			printk(KERN_ERR "Invalid gpio %d\n",
209 				gpios[i].gpio);
210 			ret = -EINVAL;
211 			goto undo;
212 		}
213 		if (!gpios[i].name) {
214 			printk(KERN_ERR "No name for gpio %d\n",
215 				gpios[i].gpio);
216 			ret = -EINVAL;
217 			goto undo;
218 		}
219 
220 		ret = gpio_request(gpios[i].gpio, gpios[i].name);
221 		if (ret)
222 			goto undo;
223 
224 		ret = gpio_direction_input(gpios[i].gpio);
225 		if (ret)
226 			goto err;
227 
228 		INIT_WORK(&gpios[i].work, gpio_work);
229 		gpios[i].jack = jack;
230 
231 		ret = request_irq(gpio_to_irq(gpios[i].gpio),
232 				gpio_handler,
233 				IRQF_TRIGGER_RISING | IRQF_TRIGGER_FALLING,
234 				jack->card->dev->driver->name,
235 				&gpios[i]);
236 		if (ret)
237 			goto err;
238 
239 #ifdef CONFIG_GPIO_SYSFS
240 		/* Expose GPIO value over sysfs for diagnostic purposes */
241 		gpio_export(gpios[i].gpio, false);
242 #endif
243 
244 		/* Update initial jack status */
245 		snd_soc_jack_gpio_detect(&gpios[i]);
246 	}
247 
248 	return 0;
249 
250 err:
251 	gpio_free(gpios[i].gpio);
252 undo:
253 	snd_soc_jack_free_gpios(jack, i, gpios);
254 
255 	return ret;
256 }
257 EXPORT_SYMBOL_GPL(snd_soc_jack_add_gpios);
258 
259 /**
260  * snd_soc_jack_free_gpios - Release GPIO pins' resources of an ASoC jack
261  *
262  * @jack:  ASoC jack
263  * @count: number of pins
264  * @gpios: array of gpio pins
265  *
266  * Release gpio and irq resources for gpio pins associated with an ASoC jack.
267  */
268 void snd_soc_jack_free_gpios(struct snd_soc_jack *jack, int count,
269 			struct snd_soc_jack_gpio *gpios)
270 {
271 	int i;
272 
273 	for (i = 0; i < count; i++) {
274 #ifdef CONFIG_GPIO_SYSFS
275 		gpio_unexport(gpios[i].gpio);
276 #endif
277 		free_irq(gpio_to_irq(gpios[i].gpio), &gpios[i]);
278 		gpio_free(gpios[i].gpio);
279 		gpios[i].jack = NULL;
280 	}
281 }
282 EXPORT_SYMBOL_GPL(snd_soc_jack_free_gpios);
283 #endif	/* CONFIG_GPIOLIB */
284