xref: /linux/sound/soc/soc-jack.c (revision f2ee442115c9b6219083c019939a9cc0c9abb2f8)
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 <linux/gpio.h>
17 #include <linux/interrupt.h>
18 #include <linux/workqueue.h>
19 #include <linux/delay.h>
20 #include <linux/export.h>
21 #include <trace/events/asoc.h>
22 
23 /**
24  * snd_soc_jack_new - Create a new jack
25  * @card:  ASoC card
26  * @id:    an identifying string for this jack
27  * @type:  a bitmask of enum snd_jack_type values that can be detected by
28  *         this jack
29  * @jack:  structure to use for the jack
30  *
31  * Creates a new jack object.
32  *
33  * Returns zero if successful, or a negative error code on failure.
34  * On success jack will be initialised.
35  */
36 int snd_soc_jack_new(struct snd_soc_codec *codec, const char *id, int type,
37 		     struct snd_soc_jack *jack)
38 {
39 	jack->codec = codec;
40 	INIT_LIST_HEAD(&jack->pins);
41 	INIT_LIST_HEAD(&jack->jack_zones);
42 	BLOCKING_INIT_NOTIFIER_HEAD(&jack->notifier);
43 
44 	return snd_jack_new(codec->card->snd_card, id, type, &jack->jack);
45 }
46 EXPORT_SYMBOL_GPL(snd_soc_jack_new);
47 
48 /**
49  * snd_soc_jack_report - Report the current status for a jack
50  *
51  * @jack:   the jack
52  * @status: a bitmask of enum snd_jack_type values that are currently detected.
53  * @mask:   a bitmask of enum snd_jack_type values that being reported.
54  *
55  * If configured using snd_soc_jack_add_pins() then the associated
56  * DAPM pins will be enabled or disabled as appropriate and DAPM
57  * synchronised.
58  *
59  * Note: This function uses mutexes and should be called from a
60  * context which can sleep (such as a workqueue).
61  */
62 void snd_soc_jack_report(struct snd_soc_jack *jack, int status, int mask)
63 {
64 	struct snd_soc_codec *codec;
65 	struct snd_soc_dapm_context *dapm;
66 	struct snd_soc_jack_pin *pin;
67 	int enable;
68 	int oldstatus;
69 
70 	trace_snd_soc_jack_report(jack, mask, status);
71 
72 	if (!jack)
73 		return;
74 
75 	codec = jack->codec;
76 	dapm =  &codec->dapm;
77 
78 	mutex_lock(&codec->mutex);
79 
80 	oldstatus = jack->status;
81 
82 	jack->status &= ~mask;
83 	jack->status |= status & mask;
84 
85 	/* The DAPM sync is expensive enough to be worth skipping.
86 	 * However, empty mask means pin synchronization is desired. */
87 	if (mask && (jack->status == oldstatus))
88 		goto out;
89 
90 	trace_snd_soc_jack_notify(jack, status);
91 
92 	list_for_each_entry(pin, &jack->pins, list) {
93 		enable = pin->mask & jack->status;
94 
95 		if (pin->invert)
96 			enable = !enable;
97 
98 		if (enable)
99 			snd_soc_dapm_enable_pin(dapm, pin->pin);
100 		else
101 			snd_soc_dapm_disable_pin(dapm, pin->pin);
102 	}
103 
104 	/* Report before the DAPM sync to help users updating micbias status */
105 	blocking_notifier_call_chain(&jack->notifier, status, jack);
106 
107 	snd_soc_dapm_sync(dapm);
108 
109 	snd_jack_report(jack->jack, jack->status);
110 
111 out:
112 	mutex_unlock(&codec->mutex);
113 }
114 EXPORT_SYMBOL_GPL(snd_soc_jack_report);
115 
116 /**
117  * snd_soc_jack_add_zones - Associate voltage zones with jack
118  *
119  * @jack:  ASoC jack
120  * @count: Number of zones
121  * @zone:  Array of zones
122  *
123  * After this function has been called the zones specified in the
124  * array will be associated with the jack.
125  */
126 int snd_soc_jack_add_zones(struct snd_soc_jack *jack, int count,
127 			  struct snd_soc_jack_zone *zones)
128 {
129 	int i;
130 
131 	for (i = 0; i < count; i++) {
132 		INIT_LIST_HEAD(&zones[i].list);
133 		list_add(&(zones[i].list), &jack->jack_zones);
134 	}
135 	return 0;
136 }
137 EXPORT_SYMBOL_GPL(snd_soc_jack_add_zones);
138 
139 /**
140  * snd_soc_jack_get_type - Based on the mic bias value, this function returns
141  * the type of jack from the zones delcared in the jack type
142  *
143  * @micbias_voltage:  mic bias voltage at adc channel when jack is plugged in
144  *
145  * Based on the mic bias value passed, this function helps identify
146  * the type of jack from the already delcared jack zones
147  */
148 int snd_soc_jack_get_type(struct snd_soc_jack *jack, int micbias_voltage)
149 {
150 	struct snd_soc_jack_zone *zone;
151 
152 	list_for_each_entry(zone, &jack->jack_zones, list) {
153 		if (micbias_voltage >= zone->min_mv &&
154 			micbias_voltage < zone->max_mv)
155 				return zone->jack_type;
156 	}
157 	return 0;
158 }
159 EXPORT_SYMBOL_GPL(snd_soc_jack_get_type);
160 
161 /**
162  * snd_soc_jack_add_pins - Associate DAPM pins with an ASoC jack
163  *
164  * @jack:  ASoC jack
165  * @count: Number of pins
166  * @pins:  Array of pins
167  *
168  * After this function has been called the DAPM pins specified in the
169  * pins array will have their status updated to reflect the current
170  * state of the jack whenever the jack status is updated.
171  */
172 int snd_soc_jack_add_pins(struct snd_soc_jack *jack, int count,
173 			  struct snd_soc_jack_pin *pins)
174 {
175 	int i;
176 
177 	for (i = 0; i < count; i++) {
178 		if (!pins[i].pin) {
179 			printk(KERN_ERR "No name for pin %d\n", i);
180 			return -EINVAL;
181 		}
182 		if (!pins[i].mask) {
183 			printk(KERN_ERR "No mask for pin %d (%s)\n", i,
184 			       pins[i].pin);
185 			return -EINVAL;
186 		}
187 
188 		INIT_LIST_HEAD(&pins[i].list);
189 		list_add(&(pins[i].list), &jack->pins);
190 	}
191 
192 	snd_soc_dapm_new_widgets(&jack->codec->card->dapm);
193 
194 	/* Update to reflect the last reported status; canned jack
195 	 * implementations are likely to set their state before the
196 	 * card has an opportunity to associate pins.
197 	 */
198 	snd_soc_jack_report(jack, 0, 0);
199 
200 	return 0;
201 }
202 EXPORT_SYMBOL_GPL(snd_soc_jack_add_pins);
203 
204 /**
205  * snd_soc_jack_notifier_register - Register a notifier for jack status
206  *
207  * @jack:  ASoC jack
208  * @nb:    Notifier block to register
209  *
210  * Register for notification of the current status of the jack.  Note
211  * that it is not possible to report additional jack events in the
212  * callback from the notifier, this is intended to support
213  * applications such as enabling electrical detection only when a
214  * mechanical detection event has occurred.
215  */
216 void snd_soc_jack_notifier_register(struct snd_soc_jack *jack,
217 				    struct notifier_block *nb)
218 {
219 	blocking_notifier_chain_register(&jack->notifier, nb);
220 }
221 EXPORT_SYMBOL_GPL(snd_soc_jack_notifier_register);
222 
223 /**
224  * snd_soc_jack_notifier_unregister - Unregister a notifier for jack status
225  *
226  * @jack:  ASoC jack
227  * @nb:    Notifier block to unregister
228  *
229  * Stop notifying for status changes.
230  */
231 void snd_soc_jack_notifier_unregister(struct snd_soc_jack *jack,
232 				      struct notifier_block *nb)
233 {
234 	blocking_notifier_chain_unregister(&jack->notifier, nb);
235 }
236 EXPORT_SYMBOL_GPL(snd_soc_jack_notifier_unregister);
237 
238 #ifdef CONFIG_GPIOLIB
239 /* gpio detect */
240 static void snd_soc_jack_gpio_detect(struct snd_soc_jack_gpio *gpio)
241 {
242 	struct snd_soc_jack *jack = gpio->jack;
243 	int enable;
244 	int report;
245 
246 	enable = gpio_get_value_cansleep(gpio->gpio);
247 	if (gpio->invert)
248 		enable = !enable;
249 
250 	if (enable)
251 		report = gpio->report;
252 	else
253 		report = 0;
254 
255 	if (gpio->jack_status_check)
256 		report = gpio->jack_status_check();
257 
258 	snd_soc_jack_report(jack, report, gpio->report);
259 }
260 
261 /* irq handler for gpio pin */
262 static irqreturn_t gpio_handler(int irq, void *data)
263 {
264 	struct snd_soc_jack_gpio *gpio = data;
265 	struct device *dev = gpio->jack->codec->card->dev;
266 
267 	trace_snd_soc_jack_irq(gpio->name);
268 
269 	if (device_may_wakeup(dev))
270 		pm_wakeup_event(dev, gpio->debounce_time + 50);
271 
272 	schedule_delayed_work(&gpio->work,
273 			      msecs_to_jiffies(gpio->debounce_time));
274 
275 	return IRQ_HANDLED;
276 }
277 
278 /* gpio work */
279 static void gpio_work(struct work_struct *work)
280 {
281 	struct snd_soc_jack_gpio *gpio;
282 
283 	gpio = container_of(work, struct snd_soc_jack_gpio, work.work);
284 	snd_soc_jack_gpio_detect(gpio);
285 }
286 
287 /**
288  * snd_soc_jack_add_gpios - Associate GPIO pins with an ASoC jack
289  *
290  * @jack:  ASoC jack
291  * @count: number of pins
292  * @gpios: array of gpio pins
293  *
294  * This function will request gpio, set data direction and request irq
295  * for each gpio in the array.
296  */
297 int snd_soc_jack_add_gpios(struct snd_soc_jack *jack, int count,
298 			struct snd_soc_jack_gpio *gpios)
299 {
300 	int i, ret;
301 
302 	for (i = 0; i < count; i++) {
303 		if (!gpio_is_valid(gpios[i].gpio)) {
304 			printk(KERN_ERR "Invalid gpio %d\n",
305 				gpios[i].gpio);
306 			ret = -EINVAL;
307 			goto undo;
308 		}
309 		if (!gpios[i].name) {
310 			printk(KERN_ERR "No name for gpio %d\n",
311 				gpios[i].gpio);
312 			ret = -EINVAL;
313 			goto undo;
314 		}
315 
316 		ret = gpio_request(gpios[i].gpio, gpios[i].name);
317 		if (ret)
318 			goto undo;
319 
320 		ret = gpio_direction_input(gpios[i].gpio);
321 		if (ret)
322 			goto err;
323 
324 		INIT_DELAYED_WORK(&gpios[i].work, gpio_work);
325 		gpios[i].jack = jack;
326 
327 		ret = request_any_context_irq(gpio_to_irq(gpios[i].gpio),
328 					      gpio_handler,
329 					      IRQF_TRIGGER_RISING |
330 					      IRQF_TRIGGER_FALLING,
331 					      gpios[i].name,
332 					      &gpios[i]);
333 		if (ret < 0)
334 			goto err;
335 
336 		if (gpios[i].wake) {
337 			ret = irq_set_irq_wake(gpio_to_irq(gpios[i].gpio), 1);
338 			if (ret != 0)
339 				printk(KERN_ERR
340 				  "Failed to mark GPIO %d as wake source: %d\n",
341 					gpios[i].gpio, ret);
342 		}
343 
344 #ifdef CONFIG_GPIO_SYSFS
345 		/* Expose GPIO value over sysfs for diagnostic purposes */
346 		gpio_export(gpios[i].gpio, false);
347 #endif
348 
349 		/* Update initial jack status */
350 		snd_soc_jack_gpio_detect(&gpios[i]);
351 	}
352 
353 	return 0;
354 
355 err:
356 	gpio_free(gpios[i].gpio);
357 undo:
358 	snd_soc_jack_free_gpios(jack, i, gpios);
359 
360 	return ret;
361 }
362 EXPORT_SYMBOL_GPL(snd_soc_jack_add_gpios);
363 
364 /**
365  * snd_soc_jack_free_gpios - Release GPIO pins' resources of an ASoC jack
366  *
367  * @jack:  ASoC jack
368  * @count: number of pins
369  * @gpios: array of gpio pins
370  *
371  * Release gpio and irq resources for gpio pins associated with an ASoC jack.
372  */
373 void snd_soc_jack_free_gpios(struct snd_soc_jack *jack, int count,
374 			struct snd_soc_jack_gpio *gpios)
375 {
376 	int i;
377 
378 	for (i = 0; i < count; i++) {
379 #ifdef CONFIG_GPIO_SYSFS
380 		gpio_unexport(gpios[i].gpio);
381 #endif
382 		free_irq(gpio_to_irq(gpios[i].gpio), &gpios[i]);
383 		cancel_delayed_work_sync(&gpios[i].work);
384 		gpio_free(gpios[i].gpio);
385 		gpios[i].jack = NULL;
386 	}
387 }
388 EXPORT_SYMBOL_GPL(snd_soc_jack_free_gpios);
389 #endif	/* CONFIG_GPIOLIB */
390