xref: /openbmc/linux/sound/soc/ti/ams-delta.c (revision 37744fee)
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * ams-delta.c  --  SoC audio for Amstrad E3 (Delta) videophone
4  *
5  * Copyright (C) 2009 Janusz Krzysztofik <jkrzyszt@tis.icnet.pl>
6  *
7  * Initially based on sound/soc/omap/osk5912.x
8  * Copyright (C) 2008 Mistral Solutions
9  */
10 
11 #include <linux/gpio/consumer.h>
12 #include <linux/spinlock.h>
13 #include <linux/tty.h>
14 #include <linux/module.h>
15 
16 #include <sound/soc.h>
17 #include <sound/jack.h>
18 
19 #include <asm/mach-types.h>
20 
21 #include <linux/platform_data/asoc-ti-mcbsp.h>
22 
23 #include "omap-mcbsp.h"
24 #include "../codecs/cx20442.h"
25 
26 static struct gpio_desc *handset_mute;
27 static struct gpio_desc *handsfree_mute;
28 
29 static int ams_delta_event_handset(struct snd_soc_dapm_widget *w,
30 				   struct snd_kcontrol *k, int event)
31 {
32 	gpiod_set_value_cansleep(handset_mute, !SND_SOC_DAPM_EVENT_ON(event));
33 	return 0;
34 }
35 
36 static int ams_delta_event_handsfree(struct snd_soc_dapm_widget *w,
37 				     struct snd_kcontrol *k, int event)
38 {
39 	gpiod_set_value_cansleep(handsfree_mute, !SND_SOC_DAPM_EVENT_ON(event));
40 	return 0;
41 }
42 
43 /* Board specific DAPM widgets */
44 static const struct snd_soc_dapm_widget ams_delta_dapm_widgets[] = {
45 	/* Handset */
46 	SND_SOC_DAPM_MIC("Mouthpiece", NULL),
47 	SND_SOC_DAPM_HP("Earpiece", ams_delta_event_handset),
48 	/* Handsfree/Speakerphone */
49 	SND_SOC_DAPM_MIC("Microphone", NULL),
50 	SND_SOC_DAPM_SPK("Speaker", ams_delta_event_handsfree),
51 };
52 
53 /* How they are connected to codec pins */
54 static const struct snd_soc_dapm_route ams_delta_audio_map[] = {
55 	{"TELIN", NULL, "Mouthpiece"},
56 	{"Earpiece", NULL, "TELOUT"},
57 
58 	{"MIC", NULL, "Microphone"},
59 	{"Speaker", NULL, "SPKOUT"},
60 };
61 
62 /*
63  * Controls, functional after the modem line discipline is activated.
64  */
65 
66 /* Virtual switch: audio input/output constellations */
67 static const char *ams_delta_audio_mode[] =
68 	{"Mixed", "Handset", "Handsfree", "Speakerphone"};
69 
70 /* Selection <-> pin translation */
71 #define AMS_DELTA_MOUTHPIECE	0
72 #define AMS_DELTA_EARPIECE	1
73 #define AMS_DELTA_MICROPHONE	2
74 #define AMS_DELTA_SPEAKER	3
75 #define AMS_DELTA_AGC		4
76 
77 #define AMS_DELTA_MIXED		((1 << AMS_DELTA_EARPIECE) | \
78 						(1 << AMS_DELTA_MICROPHONE))
79 #define AMS_DELTA_HANDSET	((1 << AMS_DELTA_MOUTHPIECE) | \
80 						(1 << AMS_DELTA_EARPIECE))
81 #define AMS_DELTA_HANDSFREE	((1 << AMS_DELTA_MICROPHONE) | \
82 						(1 << AMS_DELTA_SPEAKER))
83 #define AMS_DELTA_SPEAKERPHONE	(AMS_DELTA_HANDSFREE | (1 << AMS_DELTA_AGC))
84 
85 static const unsigned short ams_delta_audio_mode_pins[] = {
86 	AMS_DELTA_MIXED,
87 	AMS_DELTA_HANDSET,
88 	AMS_DELTA_HANDSFREE,
89 	AMS_DELTA_SPEAKERPHONE,
90 };
91 
92 static unsigned short ams_delta_audio_agc;
93 
94 /*
95  * Used for passing a codec structure pointer
96  * from the board initialization code to the tty line discipline.
97  */
98 static struct snd_soc_component *cx20442_codec;
99 
100 static int ams_delta_set_audio_mode(struct snd_kcontrol *kcontrol,
101 					struct snd_ctl_elem_value *ucontrol)
102 {
103 	struct snd_soc_card *card = snd_kcontrol_chip(kcontrol);
104 	struct snd_soc_dapm_context *dapm = &card->dapm;
105 	struct soc_enum *control = (struct soc_enum *)kcontrol->private_value;
106 	unsigned short pins;
107 	int pin, changed = 0;
108 
109 	/* Refuse any mode changes if we are not able to control the codec. */
110 	if (!cx20442_codec->card->pop_time)
111 		return -EUNATCH;
112 
113 	if (ucontrol->value.enumerated.item[0] >= control->items)
114 		return -EINVAL;
115 
116 	snd_soc_dapm_mutex_lock(dapm);
117 
118 	/* Translate selection to bitmap */
119 	pins = ams_delta_audio_mode_pins[ucontrol->value.enumerated.item[0]];
120 
121 	/* Setup pins after corresponding bits if changed */
122 	pin = !!(pins & (1 << AMS_DELTA_MOUTHPIECE));
123 
124 	if (pin != snd_soc_dapm_get_pin_status(dapm, "Mouthpiece")) {
125 		changed = 1;
126 		if (pin)
127 			snd_soc_dapm_enable_pin_unlocked(dapm, "Mouthpiece");
128 		else
129 			snd_soc_dapm_disable_pin_unlocked(dapm, "Mouthpiece");
130 	}
131 	pin = !!(pins & (1 << AMS_DELTA_EARPIECE));
132 	if (pin != snd_soc_dapm_get_pin_status(dapm, "Earpiece")) {
133 		changed = 1;
134 		if (pin)
135 			snd_soc_dapm_enable_pin_unlocked(dapm, "Earpiece");
136 		else
137 			snd_soc_dapm_disable_pin_unlocked(dapm, "Earpiece");
138 	}
139 	pin = !!(pins & (1 << AMS_DELTA_MICROPHONE));
140 	if (pin != snd_soc_dapm_get_pin_status(dapm, "Microphone")) {
141 		changed = 1;
142 		if (pin)
143 			snd_soc_dapm_enable_pin_unlocked(dapm, "Microphone");
144 		else
145 			snd_soc_dapm_disable_pin_unlocked(dapm, "Microphone");
146 	}
147 	pin = !!(pins & (1 << AMS_DELTA_SPEAKER));
148 	if (pin != snd_soc_dapm_get_pin_status(dapm, "Speaker")) {
149 		changed = 1;
150 		if (pin)
151 			snd_soc_dapm_enable_pin_unlocked(dapm, "Speaker");
152 		else
153 			snd_soc_dapm_disable_pin_unlocked(dapm, "Speaker");
154 	}
155 	pin = !!(pins & (1 << AMS_DELTA_AGC));
156 	if (pin != ams_delta_audio_agc) {
157 		ams_delta_audio_agc = pin;
158 		changed = 1;
159 		if (pin)
160 			snd_soc_dapm_enable_pin_unlocked(dapm, "AGCIN");
161 		else
162 			snd_soc_dapm_disable_pin_unlocked(dapm, "AGCIN");
163 	}
164 
165 	if (changed)
166 		snd_soc_dapm_sync_unlocked(dapm);
167 
168 	snd_soc_dapm_mutex_unlock(dapm);
169 
170 	return changed;
171 }
172 
173 static int ams_delta_get_audio_mode(struct snd_kcontrol *kcontrol,
174 					struct snd_ctl_elem_value *ucontrol)
175 {
176 	struct snd_soc_card *card = snd_kcontrol_chip(kcontrol);
177 	struct snd_soc_dapm_context *dapm = &card->dapm;
178 	unsigned short pins, mode;
179 
180 	pins = ((snd_soc_dapm_get_pin_status(dapm, "Mouthpiece") <<
181 							AMS_DELTA_MOUTHPIECE) |
182 			(snd_soc_dapm_get_pin_status(dapm, "Earpiece") <<
183 							AMS_DELTA_EARPIECE));
184 	if (pins)
185 		pins |= (snd_soc_dapm_get_pin_status(dapm, "Microphone") <<
186 							AMS_DELTA_MICROPHONE);
187 	else
188 		pins = ((snd_soc_dapm_get_pin_status(dapm, "Microphone") <<
189 							AMS_DELTA_MICROPHONE) |
190 			(snd_soc_dapm_get_pin_status(dapm, "Speaker") <<
191 							AMS_DELTA_SPEAKER) |
192 			(ams_delta_audio_agc << AMS_DELTA_AGC));
193 
194 	for (mode = 0; mode < ARRAY_SIZE(ams_delta_audio_mode); mode++)
195 		if (pins == ams_delta_audio_mode_pins[mode])
196 			break;
197 
198 	if (mode >= ARRAY_SIZE(ams_delta_audio_mode))
199 		return -EINVAL;
200 
201 	ucontrol->value.enumerated.item[0] = mode;
202 
203 	return 0;
204 }
205 
206 static SOC_ENUM_SINGLE_EXT_DECL(ams_delta_audio_enum,
207 				      ams_delta_audio_mode);
208 
209 static const struct snd_kcontrol_new ams_delta_audio_controls[] = {
210 	SOC_ENUM_EXT("Audio Mode", ams_delta_audio_enum,
211 			ams_delta_get_audio_mode, ams_delta_set_audio_mode),
212 };
213 
214 /* Hook switch */
215 static struct snd_soc_jack ams_delta_hook_switch;
216 static struct snd_soc_jack_gpio ams_delta_hook_switch_gpios[] = {
217 	{
218 		.name = "hook_switch",
219 		.report = SND_JACK_HEADSET,
220 		.invert = 1,
221 		.debounce_time = 150,
222 	}
223 };
224 
225 /* After we are able to control the codec over the modem,
226  * the hook switch can be used for dynamic DAPM reconfiguration. */
227 static struct snd_soc_jack_pin ams_delta_hook_switch_pins[] = {
228 	/* Handset */
229 	{
230 		.pin = "Mouthpiece",
231 		.mask = SND_JACK_MICROPHONE,
232 	},
233 	{
234 		.pin = "Earpiece",
235 		.mask = SND_JACK_HEADPHONE,
236 	},
237 	/* Handsfree */
238 	{
239 		.pin = "Microphone",
240 		.mask = SND_JACK_MICROPHONE,
241 		.invert = 1,
242 	},
243 	{
244 		.pin = "Speaker",
245 		.mask = SND_JACK_HEADPHONE,
246 		.invert = 1,
247 	},
248 };
249 
250 
251 /*
252  * Modem line discipline, required for making above controls functional.
253  * Activated from userspace with ldattach, possibly invoked from udev rule.
254  */
255 
256 /* To actually apply any modem controlled configuration changes to the codec,
257  * we must connect codec DAI pins to the modem for a moment.  Be careful not
258  * to interfere with our digital mute function that shares the same hardware. */
259 static struct timer_list cx81801_timer;
260 static bool cx81801_cmd_pending;
261 static bool ams_delta_muted;
262 static DEFINE_SPINLOCK(ams_delta_lock);
263 static struct gpio_desc *gpiod_modem_codec;
264 
265 static void cx81801_timeout(struct timer_list *unused)
266 {
267 	int muted;
268 
269 	spin_lock(&ams_delta_lock);
270 	cx81801_cmd_pending = 0;
271 	muted = ams_delta_muted;
272 	spin_unlock(&ams_delta_lock);
273 
274 	/* Reconnect the codec DAI back from the modem to the CPU DAI
275 	 * only if digital mute still off */
276 	if (!muted)
277 		gpiod_set_value(gpiod_modem_codec, 0);
278 }
279 
280 /* Line discipline .open() */
281 static int cx81801_open(struct tty_struct *tty)
282 {
283 	int ret;
284 
285 	if (!cx20442_codec)
286 		return -ENODEV;
287 
288 	/*
289 	 * Pass the codec structure pointer for use by other ldisc callbacks,
290 	 * both the card and the codec specific parts.
291 	 */
292 	tty->disc_data = cx20442_codec;
293 
294 	ret = v253_ops.open(tty);
295 
296 	if (ret < 0)
297 		tty->disc_data = NULL;
298 
299 	return ret;
300 }
301 
302 /* Line discipline .close() */
303 static void cx81801_close(struct tty_struct *tty)
304 {
305 	struct snd_soc_component *component = tty->disc_data;
306 	struct snd_soc_dapm_context *dapm = &component->card->dapm;
307 
308 	del_timer_sync(&cx81801_timer);
309 
310 	/* Prevent the hook switch from further changing the DAPM pins */
311 	INIT_LIST_HEAD(&ams_delta_hook_switch.pins);
312 
313 	if (!component)
314 		return;
315 
316 	v253_ops.close(tty);
317 
318 	/* Revert back to default audio input/output constellation */
319 	snd_soc_dapm_mutex_lock(dapm);
320 
321 	snd_soc_dapm_disable_pin_unlocked(dapm, "Mouthpiece");
322 	snd_soc_dapm_enable_pin_unlocked(dapm, "Earpiece");
323 	snd_soc_dapm_enable_pin_unlocked(dapm, "Microphone");
324 	snd_soc_dapm_disable_pin_unlocked(dapm, "Speaker");
325 	snd_soc_dapm_disable_pin_unlocked(dapm, "AGCIN");
326 
327 	snd_soc_dapm_sync_unlocked(dapm);
328 
329 	snd_soc_dapm_mutex_unlock(dapm);
330 }
331 
332 /* Line discipline .hangup() */
333 static int cx81801_hangup(struct tty_struct *tty)
334 {
335 	cx81801_close(tty);
336 	return 0;
337 }
338 
339 /* Line discipline .receive_buf() */
340 static void cx81801_receive(struct tty_struct *tty,
341 				const unsigned char *cp, char *fp, int count)
342 {
343 	struct snd_soc_component *component = tty->disc_data;
344 	const unsigned char *c;
345 	int apply, ret;
346 
347 	if (!component)
348 		return;
349 
350 	if (!component->card->pop_time) {
351 		/* First modem response, complete setup procedure */
352 
353 		/* Initialize timer used for config pulse generation */
354 		timer_setup(&cx81801_timer, cx81801_timeout, 0);
355 
356 		v253_ops.receive_buf(tty, cp, fp, count);
357 
358 		/* Link hook switch to DAPM pins */
359 		ret = snd_soc_jack_add_pins(&ams_delta_hook_switch,
360 					ARRAY_SIZE(ams_delta_hook_switch_pins),
361 					ams_delta_hook_switch_pins);
362 		if (ret)
363 			dev_warn(component->dev,
364 				"Failed to link hook switch to DAPM pins, "
365 				"will continue with hook switch unlinked.\n");
366 
367 		return;
368 	}
369 
370 	v253_ops.receive_buf(tty, cp, fp, count);
371 
372 	for (c = &cp[count - 1]; c >= cp; c--) {
373 		if (*c != '\r')
374 			continue;
375 		/* Complete modem response received, apply config to codec */
376 
377 		spin_lock_bh(&ams_delta_lock);
378 		mod_timer(&cx81801_timer, jiffies + msecs_to_jiffies(150));
379 		apply = !ams_delta_muted && !cx81801_cmd_pending;
380 		cx81801_cmd_pending = 1;
381 		spin_unlock_bh(&ams_delta_lock);
382 
383 		/* Apply config pulse by connecting the codec to the modem
384 		 * if not already done */
385 		if (apply)
386 			gpiod_set_value(gpiod_modem_codec, 1);
387 		break;
388 	}
389 }
390 
391 /* Line discipline .write_wakeup() */
392 static void cx81801_wakeup(struct tty_struct *tty)
393 {
394 	v253_ops.write_wakeup(tty);
395 }
396 
397 static struct tty_ldisc_ops cx81801_ops = {
398 	.magic = TTY_LDISC_MAGIC,
399 	.name = "cx81801",
400 	.owner = THIS_MODULE,
401 	.open = cx81801_open,
402 	.close = cx81801_close,
403 	.hangup = cx81801_hangup,
404 	.receive_buf = cx81801_receive,
405 	.write_wakeup = cx81801_wakeup,
406 };
407 
408 
409 /*
410  * Even if not very useful, the sound card can still work without any of the
411  * above functonality activated.  You can still control its audio input/output
412  * constellation and speakerphone gain from userspace by issuing AT commands
413  * over the modem port.
414  */
415 
416 static struct snd_soc_ops ams_delta_ops;
417 
418 
419 /* Digital mute implemented using modem/CPU multiplexer.
420  * Shares hardware with codec config pulse generation */
421 static bool ams_delta_muted = 1;
422 
423 static int ams_delta_digital_mute(struct snd_soc_dai *dai, int mute)
424 {
425 	int apply;
426 
427 	if (ams_delta_muted == mute)
428 		return 0;
429 
430 	spin_lock_bh(&ams_delta_lock);
431 	ams_delta_muted = mute;
432 	apply = !cx81801_cmd_pending;
433 	spin_unlock_bh(&ams_delta_lock);
434 
435 	if (apply)
436 		gpiod_set_value(gpiod_modem_codec, !!mute);
437 	return 0;
438 }
439 
440 /* Our codec DAI probably doesn't have its own .ops structure */
441 static const struct snd_soc_dai_ops ams_delta_dai_ops = {
442 	.digital_mute = ams_delta_digital_mute,
443 };
444 
445 /* Will be used if the codec ever has its own digital_mute function */
446 static int ams_delta_startup(struct snd_pcm_substream *substream)
447 {
448 	return ams_delta_digital_mute(NULL, 0);
449 }
450 
451 static void ams_delta_shutdown(struct snd_pcm_substream *substream)
452 {
453 	ams_delta_digital_mute(NULL, 1);
454 }
455 
456 
457 /*
458  * Card initialization
459  */
460 
461 static int ams_delta_cx20442_init(struct snd_soc_pcm_runtime *rtd)
462 {
463 	struct snd_soc_dai *codec_dai = asoc_rtd_to_codec(rtd, 0);
464 	struct snd_soc_card *card = rtd->card;
465 	struct snd_soc_dapm_context *dapm = &card->dapm;
466 	int ret;
467 	/* Codec is ready, now add/activate board specific controls */
468 
469 	/* Store a pointer to the codec structure for tty ldisc use */
470 	cx20442_codec = asoc_rtd_to_codec(rtd, 0)->component;
471 
472 	/* Add hook switch - can be used to control the codec from userspace
473 	 * even if line discipline fails */
474 	ret = snd_soc_card_jack_new(card, "hook_switch", SND_JACK_HEADSET,
475 				    &ams_delta_hook_switch, NULL, 0);
476 	if (ret)
477 		dev_warn(card->dev,
478 				"Failed to allocate resources for hook switch, "
479 				"will continue without one.\n");
480 	else {
481 		ret = snd_soc_jack_add_gpiods(card->dev, &ams_delta_hook_switch,
482 					ARRAY_SIZE(ams_delta_hook_switch_gpios),
483 					ams_delta_hook_switch_gpios);
484 		if (ret)
485 			dev_warn(card->dev,
486 				"Failed to set up hook switch GPIO line, "
487 				"will continue with hook switch inactive.\n");
488 	}
489 
490 	gpiod_modem_codec = devm_gpiod_get(card->dev, "modem_codec",
491 					   GPIOD_OUT_HIGH);
492 	if (IS_ERR(gpiod_modem_codec)) {
493 		dev_warn(card->dev, "Failed to obtain modem_codec GPIO\n");
494 		return 0;
495 	}
496 
497 	/* Set up digital mute if not provided by the codec */
498 	if (!codec_dai->driver->ops) {
499 		codec_dai->driver->ops = &ams_delta_dai_ops;
500 	} else {
501 		ams_delta_ops.startup = ams_delta_startup;
502 		ams_delta_ops.shutdown = ams_delta_shutdown;
503 	}
504 
505 	/* Register optional line discipline for over the modem control */
506 	ret = tty_register_ldisc(N_V253, &cx81801_ops);
507 	if (ret) {
508 		dev_warn(card->dev,
509 				"Failed to register line discipline, "
510 				"will continue without any controls.\n");
511 		return 0;
512 	}
513 
514 	/* Set up initial pin constellation */
515 	snd_soc_dapm_disable_pin(dapm, "Mouthpiece");
516 	snd_soc_dapm_disable_pin(dapm, "Speaker");
517 	snd_soc_dapm_disable_pin(dapm, "AGCIN");
518 	snd_soc_dapm_disable_pin(dapm, "AGCOUT");
519 
520 	return 0;
521 }
522 
523 /* DAI glue - connects codec <--> CPU */
524 SND_SOC_DAILINK_DEFS(cx20442,
525 	DAILINK_COMP_ARRAY(COMP_CPU("omap-mcbsp.1")),
526 	DAILINK_COMP_ARRAY(COMP_CODEC("cx20442-codec", "cx20442-voice")),
527 	DAILINK_COMP_ARRAY(COMP_PLATFORM("omap-mcbsp.1")));
528 
529 static struct snd_soc_dai_link ams_delta_dai_link = {
530 	.name = "CX20442",
531 	.stream_name = "CX20442",
532 	.init = ams_delta_cx20442_init,
533 	.ops = &ams_delta_ops,
534 	.dai_fmt = SND_SOC_DAIFMT_DSP_A | SND_SOC_DAIFMT_NB_NF |
535 		   SND_SOC_DAIFMT_CBM_CFM,
536 	SND_SOC_DAILINK_REG(cx20442),
537 };
538 
539 /* Audio card driver */
540 static struct snd_soc_card ams_delta_audio_card = {
541 	.name = "AMS_DELTA",
542 	.owner = THIS_MODULE,
543 	.dai_link = &ams_delta_dai_link,
544 	.num_links = 1,
545 
546 	.controls = ams_delta_audio_controls,
547 	.num_controls = ARRAY_SIZE(ams_delta_audio_controls),
548 	.dapm_widgets = ams_delta_dapm_widgets,
549 	.num_dapm_widgets = ARRAY_SIZE(ams_delta_dapm_widgets),
550 	.dapm_routes = ams_delta_audio_map,
551 	.num_dapm_routes = ARRAY_SIZE(ams_delta_audio_map),
552 };
553 
554 /* Module init/exit */
555 static int ams_delta_probe(struct platform_device *pdev)
556 {
557 	struct snd_soc_card *card = &ams_delta_audio_card;
558 	int ret;
559 
560 	card->dev = &pdev->dev;
561 
562 	handset_mute = devm_gpiod_get(card->dev, "handset_mute",
563 				      GPIOD_OUT_HIGH);
564 	if (IS_ERR(handset_mute))
565 		return PTR_ERR(handset_mute);
566 
567 	handsfree_mute = devm_gpiod_get(card->dev, "handsfree_mute",
568 					GPIOD_OUT_HIGH);
569 	if (IS_ERR(handsfree_mute))
570 		return PTR_ERR(handsfree_mute);
571 
572 	ret = snd_soc_register_card(card);
573 	if (ret) {
574 		dev_err(&pdev->dev, "snd_soc_register_card failed (%d)\n", ret);
575 		card->dev = NULL;
576 		return ret;
577 	}
578 	return 0;
579 }
580 
581 static int ams_delta_remove(struct platform_device *pdev)
582 {
583 	struct snd_soc_card *card = platform_get_drvdata(pdev);
584 
585 	if (tty_unregister_ldisc(N_V253) != 0)
586 		dev_warn(&pdev->dev,
587 			"failed to unregister V253 line discipline\n");
588 
589 	snd_soc_unregister_card(card);
590 	card->dev = NULL;
591 	return 0;
592 }
593 
594 #define DRV_NAME "ams-delta-audio"
595 
596 static struct platform_driver ams_delta_driver = {
597 	.driver = {
598 		.name = DRV_NAME,
599 	},
600 	.probe = ams_delta_probe,
601 	.remove = ams_delta_remove,
602 };
603 
604 module_platform_driver(ams_delta_driver);
605 
606 MODULE_AUTHOR("Janusz Krzysztofik <jkrzyszt@tis.icnet.pl>");
607 MODULE_DESCRIPTION("ALSA SoC driver for Amstrad E3 (Delta) videophone");
608 MODULE_LICENSE("GPL");
609 MODULE_ALIAS("platform:" DRV_NAME);
610