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