xref: /openbmc/linux/sound/soc/ti/ams-delta.c (revision b830f94f)
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 /* Board specific DAPM widgets */
27 static const struct snd_soc_dapm_widget ams_delta_dapm_widgets[] = {
28 	/* Handset */
29 	SND_SOC_DAPM_MIC("Mouthpiece", NULL),
30 	SND_SOC_DAPM_HP("Earpiece", NULL),
31 	/* Handsfree/Speakerphone */
32 	SND_SOC_DAPM_MIC("Microphone", NULL),
33 	SND_SOC_DAPM_SPK("Speaker", NULL),
34 };
35 
36 /* How they are connected to codec pins */
37 static const struct snd_soc_dapm_route ams_delta_audio_map[] = {
38 	{"TELIN", NULL, "Mouthpiece"},
39 	{"Earpiece", NULL, "TELOUT"},
40 
41 	{"MIC", NULL, "Microphone"},
42 	{"Speaker", NULL, "SPKOUT"},
43 };
44 
45 /*
46  * Controls, functional after the modem line discipline is activated.
47  */
48 
49 /* Virtual switch: audio input/output constellations */
50 static const char *ams_delta_audio_mode[] =
51 	{"Mixed", "Handset", "Handsfree", "Speakerphone"};
52 
53 /* Selection <-> pin translation */
54 #define AMS_DELTA_MOUTHPIECE	0
55 #define AMS_DELTA_EARPIECE	1
56 #define AMS_DELTA_MICROPHONE	2
57 #define AMS_DELTA_SPEAKER	3
58 #define AMS_DELTA_AGC		4
59 
60 #define AMS_DELTA_MIXED		((1 << AMS_DELTA_EARPIECE) | \
61 						(1 << AMS_DELTA_MICROPHONE))
62 #define AMS_DELTA_HANDSET	((1 << AMS_DELTA_MOUTHPIECE) | \
63 						(1 << AMS_DELTA_EARPIECE))
64 #define AMS_DELTA_HANDSFREE	((1 << AMS_DELTA_MICROPHONE) | \
65 						(1 << AMS_DELTA_SPEAKER))
66 #define AMS_DELTA_SPEAKERPHONE	(AMS_DELTA_HANDSFREE | (1 << AMS_DELTA_AGC))
67 
68 static const unsigned short ams_delta_audio_mode_pins[] = {
69 	AMS_DELTA_MIXED,
70 	AMS_DELTA_HANDSET,
71 	AMS_DELTA_HANDSFREE,
72 	AMS_DELTA_SPEAKERPHONE,
73 };
74 
75 static unsigned short ams_delta_audio_agc;
76 
77 /*
78  * Used for passing a codec structure pointer
79  * from the board initialization code to the tty line discipline.
80  */
81 static struct snd_soc_component *cx20442_codec;
82 
83 static int ams_delta_set_audio_mode(struct snd_kcontrol *kcontrol,
84 					struct snd_ctl_elem_value *ucontrol)
85 {
86 	struct snd_soc_card *card = snd_kcontrol_chip(kcontrol);
87 	struct snd_soc_dapm_context *dapm = &card->dapm;
88 	struct soc_enum *control = (struct soc_enum *)kcontrol->private_value;
89 	unsigned short pins;
90 	int pin, changed = 0;
91 
92 	/* Refuse any mode changes if we are not able to control the codec. */
93 	if (!cx20442_codec->card->pop_time)
94 		return -EUNATCH;
95 
96 	if (ucontrol->value.enumerated.item[0] >= control->items)
97 		return -EINVAL;
98 
99 	snd_soc_dapm_mutex_lock(dapm);
100 
101 	/* Translate selection to bitmap */
102 	pins = ams_delta_audio_mode_pins[ucontrol->value.enumerated.item[0]];
103 
104 	/* Setup pins after corresponding bits if changed */
105 	pin = !!(pins & (1 << AMS_DELTA_MOUTHPIECE));
106 
107 	if (pin != snd_soc_dapm_get_pin_status(dapm, "Mouthpiece")) {
108 		changed = 1;
109 		if (pin)
110 			snd_soc_dapm_enable_pin_unlocked(dapm, "Mouthpiece");
111 		else
112 			snd_soc_dapm_disable_pin_unlocked(dapm, "Mouthpiece");
113 	}
114 	pin = !!(pins & (1 << AMS_DELTA_EARPIECE));
115 	if (pin != snd_soc_dapm_get_pin_status(dapm, "Earpiece")) {
116 		changed = 1;
117 		if (pin)
118 			snd_soc_dapm_enable_pin_unlocked(dapm, "Earpiece");
119 		else
120 			snd_soc_dapm_disable_pin_unlocked(dapm, "Earpiece");
121 	}
122 	pin = !!(pins & (1 << AMS_DELTA_MICROPHONE));
123 	if (pin != snd_soc_dapm_get_pin_status(dapm, "Microphone")) {
124 		changed = 1;
125 		if (pin)
126 			snd_soc_dapm_enable_pin_unlocked(dapm, "Microphone");
127 		else
128 			snd_soc_dapm_disable_pin_unlocked(dapm, "Microphone");
129 	}
130 	pin = !!(pins & (1 << AMS_DELTA_SPEAKER));
131 	if (pin != snd_soc_dapm_get_pin_status(dapm, "Speaker")) {
132 		changed = 1;
133 		if (pin)
134 			snd_soc_dapm_enable_pin_unlocked(dapm, "Speaker");
135 		else
136 			snd_soc_dapm_disable_pin_unlocked(dapm, "Speaker");
137 	}
138 	pin = !!(pins & (1 << AMS_DELTA_AGC));
139 	if (pin != ams_delta_audio_agc) {
140 		ams_delta_audio_agc = pin;
141 		changed = 1;
142 		if (pin)
143 			snd_soc_dapm_enable_pin_unlocked(dapm, "AGCIN");
144 		else
145 			snd_soc_dapm_disable_pin_unlocked(dapm, "AGCIN");
146 	}
147 
148 	if (changed)
149 		snd_soc_dapm_sync_unlocked(dapm);
150 
151 	snd_soc_dapm_mutex_unlock(dapm);
152 
153 	return changed;
154 }
155 
156 static int ams_delta_get_audio_mode(struct snd_kcontrol *kcontrol,
157 					struct snd_ctl_elem_value *ucontrol)
158 {
159 	struct snd_soc_card *card = snd_kcontrol_chip(kcontrol);
160 	struct snd_soc_dapm_context *dapm = &card->dapm;
161 	unsigned short pins, mode;
162 
163 	pins = ((snd_soc_dapm_get_pin_status(dapm, "Mouthpiece") <<
164 							AMS_DELTA_MOUTHPIECE) |
165 			(snd_soc_dapm_get_pin_status(dapm, "Earpiece") <<
166 							AMS_DELTA_EARPIECE));
167 	if (pins)
168 		pins |= (snd_soc_dapm_get_pin_status(dapm, "Microphone") <<
169 							AMS_DELTA_MICROPHONE);
170 	else
171 		pins = ((snd_soc_dapm_get_pin_status(dapm, "Microphone") <<
172 							AMS_DELTA_MICROPHONE) |
173 			(snd_soc_dapm_get_pin_status(dapm, "Speaker") <<
174 							AMS_DELTA_SPEAKER) |
175 			(ams_delta_audio_agc << AMS_DELTA_AGC));
176 
177 	for (mode = 0; mode < ARRAY_SIZE(ams_delta_audio_mode); mode++)
178 		if (pins == ams_delta_audio_mode_pins[mode])
179 			break;
180 
181 	if (mode >= ARRAY_SIZE(ams_delta_audio_mode))
182 		return -EINVAL;
183 
184 	ucontrol->value.enumerated.item[0] = mode;
185 
186 	return 0;
187 }
188 
189 static SOC_ENUM_SINGLE_EXT_DECL(ams_delta_audio_enum,
190 				      ams_delta_audio_mode);
191 
192 static const struct snd_kcontrol_new ams_delta_audio_controls[] = {
193 	SOC_ENUM_EXT("Audio Mode", ams_delta_audio_enum,
194 			ams_delta_get_audio_mode, ams_delta_set_audio_mode),
195 };
196 
197 /* Hook switch */
198 static struct snd_soc_jack ams_delta_hook_switch;
199 static struct snd_soc_jack_gpio ams_delta_hook_switch_gpios[] = {
200 	{
201 		.name = "hook_switch",
202 		.report = SND_JACK_HEADSET,
203 		.invert = 1,
204 		.debounce_time = 150,
205 	}
206 };
207 
208 /* After we are able to control the codec over the modem,
209  * the hook switch can be used for dynamic DAPM reconfiguration. */
210 static struct snd_soc_jack_pin ams_delta_hook_switch_pins[] = {
211 	/* Handset */
212 	{
213 		.pin = "Mouthpiece",
214 		.mask = SND_JACK_MICROPHONE,
215 	},
216 	{
217 		.pin = "Earpiece",
218 		.mask = SND_JACK_HEADPHONE,
219 	},
220 	/* Handsfree */
221 	{
222 		.pin = "Microphone",
223 		.mask = SND_JACK_MICROPHONE,
224 		.invert = 1,
225 	},
226 	{
227 		.pin = "Speaker",
228 		.mask = SND_JACK_HEADPHONE,
229 		.invert = 1,
230 	},
231 };
232 
233 
234 /*
235  * Modem line discipline, required for making above controls functional.
236  * Activated from userspace with ldattach, possibly invoked from udev rule.
237  */
238 
239 /* To actually apply any modem controlled configuration changes to the codec,
240  * we must connect codec DAI pins to the modem for a moment.  Be careful not
241  * to interfere with our digital mute function that shares the same hardware. */
242 static struct timer_list cx81801_timer;
243 static bool cx81801_cmd_pending;
244 static bool ams_delta_muted;
245 static DEFINE_SPINLOCK(ams_delta_lock);
246 static struct gpio_desc *gpiod_modem_codec;
247 
248 static void cx81801_timeout(struct timer_list *unused)
249 {
250 	int muted;
251 
252 	spin_lock(&ams_delta_lock);
253 	cx81801_cmd_pending = 0;
254 	muted = ams_delta_muted;
255 	spin_unlock(&ams_delta_lock);
256 
257 	/* Reconnect the codec DAI back from the modem to the CPU DAI
258 	 * only if digital mute still off */
259 	if (!muted)
260 		gpiod_set_value(gpiod_modem_codec, 0);
261 }
262 
263 /* Line discipline .open() */
264 static int cx81801_open(struct tty_struct *tty)
265 {
266 	int ret;
267 
268 	if (!cx20442_codec)
269 		return -ENODEV;
270 
271 	/*
272 	 * Pass the codec structure pointer for use by other ldisc callbacks,
273 	 * both the card and the codec specific parts.
274 	 */
275 	tty->disc_data = cx20442_codec;
276 
277 	ret = v253_ops.open(tty);
278 
279 	if (ret < 0)
280 		tty->disc_data = NULL;
281 
282 	return ret;
283 }
284 
285 /* Line discipline .close() */
286 static void cx81801_close(struct tty_struct *tty)
287 {
288 	struct snd_soc_component *component = tty->disc_data;
289 	struct snd_soc_dapm_context *dapm = &component->card->dapm;
290 
291 	del_timer_sync(&cx81801_timer);
292 
293 	/* Prevent the hook switch from further changing the DAPM pins */
294 	INIT_LIST_HEAD(&ams_delta_hook_switch.pins);
295 
296 	if (!component)
297 		return;
298 
299 	v253_ops.close(tty);
300 
301 	/* Revert back to default audio input/output constellation */
302 	snd_soc_dapm_mutex_lock(dapm);
303 
304 	snd_soc_dapm_disable_pin_unlocked(dapm, "Mouthpiece");
305 	snd_soc_dapm_enable_pin_unlocked(dapm, "Earpiece");
306 	snd_soc_dapm_enable_pin_unlocked(dapm, "Microphone");
307 	snd_soc_dapm_disable_pin_unlocked(dapm, "Speaker");
308 	snd_soc_dapm_disable_pin_unlocked(dapm, "AGCIN");
309 
310 	snd_soc_dapm_sync_unlocked(dapm);
311 
312 	snd_soc_dapm_mutex_unlock(dapm);
313 }
314 
315 /* Line discipline .hangup() */
316 static int cx81801_hangup(struct tty_struct *tty)
317 {
318 	cx81801_close(tty);
319 	return 0;
320 }
321 
322 /* Line discipline .receive_buf() */
323 static void cx81801_receive(struct tty_struct *tty,
324 				const unsigned char *cp, char *fp, int count)
325 {
326 	struct snd_soc_component *component = tty->disc_data;
327 	const unsigned char *c;
328 	int apply, ret;
329 
330 	if (!component)
331 		return;
332 
333 	if (!component->card->pop_time) {
334 		/* First modem response, complete setup procedure */
335 
336 		/* Initialize timer used for config pulse generation */
337 		timer_setup(&cx81801_timer, cx81801_timeout, 0);
338 
339 		v253_ops.receive_buf(tty, cp, fp, count);
340 
341 		/* Link hook switch to DAPM pins */
342 		ret = snd_soc_jack_add_pins(&ams_delta_hook_switch,
343 					ARRAY_SIZE(ams_delta_hook_switch_pins),
344 					ams_delta_hook_switch_pins);
345 		if (ret)
346 			dev_warn(component->dev,
347 				"Failed to link hook switch to DAPM pins, "
348 				"will continue with hook switch unlinked.\n");
349 
350 		return;
351 	}
352 
353 	v253_ops.receive_buf(tty, cp, fp, count);
354 
355 	for (c = &cp[count - 1]; c >= cp; c--) {
356 		if (*c != '\r')
357 			continue;
358 		/* Complete modem response received, apply config to codec */
359 
360 		spin_lock_bh(&ams_delta_lock);
361 		mod_timer(&cx81801_timer, jiffies + msecs_to_jiffies(150));
362 		apply = !ams_delta_muted && !cx81801_cmd_pending;
363 		cx81801_cmd_pending = 1;
364 		spin_unlock_bh(&ams_delta_lock);
365 
366 		/* Apply config pulse by connecting the codec to the modem
367 		 * if not already done */
368 		if (apply)
369 			gpiod_set_value(gpiod_modem_codec, 1);
370 		break;
371 	}
372 }
373 
374 /* Line discipline .write_wakeup() */
375 static void cx81801_wakeup(struct tty_struct *tty)
376 {
377 	v253_ops.write_wakeup(tty);
378 }
379 
380 static struct tty_ldisc_ops cx81801_ops = {
381 	.magic = TTY_LDISC_MAGIC,
382 	.name = "cx81801",
383 	.owner = THIS_MODULE,
384 	.open = cx81801_open,
385 	.close = cx81801_close,
386 	.hangup = cx81801_hangup,
387 	.receive_buf = cx81801_receive,
388 	.write_wakeup = cx81801_wakeup,
389 };
390 
391 
392 /*
393  * Even if not very useful, the sound card can still work without any of the
394  * above functonality activated.  You can still control its audio input/output
395  * constellation and speakerphone gain from userspace by issuing AT commands
396  * over the modem port.
397  */
398 
399 static struct snd_soc_ops ams_delta_ops;
400 
401 
402 /* Digital mute implemented using modem/CPU multiplexer.
403  * Shares hardware with codec config pulse generation */
404 static bool ams_delta_muted = 1;
405 
406 static int ams_delta_digital_mute(struct snd_soc_dai *dai, int mute)
407 {
408 	int apply;
409 
410 	if (ams_delta_muted == mute)
411 		return 0;
412 
413 	spin_lock_bh(&ams_delta_lock);
414 	ams_delta_muted = mute;
415 	apply = !cx81801_cmd_pending;
416 	spin_unlock_bh(&ams_delta_lock);
417 
418 	if (apply)
419 		gpiod_set_value(gpiod_modem_codec, !!mute);
420 	return 0;
421 }
422 
423 /* Our codec DAI probably doesn't have its own .ops structure */
424 static const struct snd_soc_dai_ops ams_delta_dai_ops = {
425 	.digital_mute = ams_delta_digital_mute,
426 };
427 
428 /* Will be used if the codec ever has its own digital_mute function */
429 static int ams_delta_startup(struct snd_pcm_substream *substream)
430 {
431 	return ams_delta_digital_mute(NULL, 0);
432 }
433 
434 static void ams_delta_shutdown(struct snd_pcm_substream *substream)
435 {
436 	ams_delta_digital_mute(NULL, 1);
437 }
438 
439 
440 /*
441  * Card initialization
442  */
443 
444 static int ams_delta_cx20442_init(struct snd_soc_pcm_runtime *rtd)
445 {
446 	struct snd_soc_dai *codec_dai = rtd->codec_dai;
447 	struct snd_soc_card *card = rtd->card;
448 	struct snd_soc_dapm_context *dapm = &card->dapm;
449 	int ret;
450 	/* Codec is ready, now add/activate board specific controls */
451 
452 	/* Store a pointer to the codec structure for tty ldisc use */
453 	cx20442_codec = rtd->codec_dai->component;
454 
455 	/* Add hook switch - can be used to control the codec from userspace
456 	 * even if line discipline fails */
457 	ret = snd_soc_card_jack_new(card, "hook_switch", SND_JACK_HEADSET,
458 				    &ams_delta_hook_switch, NULL, 0);
459 	if (ret)
460 		dev_warn(card->dev,
461 				"Failed to allocate resources for hook switch, "
462 				"will continue without one.\n");
463 	else {
464 		ret = snd_soc_jack_add_gpiods(card->dev, &ams_delta_hook_switch,
465 					ARRAY_SIZE(ams_delta_hook_switch_gpios),
466 					ams_delta_hook_switch_gpios);
467 		if (ret)
468 			dev_warn(card->dev,
469 				"Failed to set up hook switch GPIO line, "
470 				"will continue with hook switch inactive.\n");
471 	}
472 
473 	gpiod_modem_codec = devm_gpiod_get(card->dev, "modem_codec",
474 					   GPIOD_OUT_HIGH);
475 	if (IS_ERR(gpiod_modem_codec)) {
476 		dev_warn(card->dev, "Failed to obtain modem_codec GPIO\n");
477 		return 0;
478 	}
479 
480 	/* Set up digital mute if not provided by the codec */
481 	if (!codec_dai->driver->ops) {
482 		codec_dai->driver->ops = &ams_delta_dai_ops;
483 	} else {
484 		ams_delta_ops.startup = ams_delta_startup;
485 		ams_delta_ops.shutdown = ams_delta_shutdown;
486 	}
487 
488 	/* Register optional line discipline for over the modem control */
489 	ret = tty_register_ldisc(N_V253, &cx81801_ops);
490 	if (ret) {
491 		dev_warn(card->dev,
492 				"Failed to register line discipline, "
493 				"will continue without any controls.\n");
494 		return 0;
495 	}
496 
497 	/* Set up initial pin constellation */
498 	snd_soc_dapm_disable_pin(dapm, "Mouthpiece");
499 	snd_soc_dapm_disable_pin(dapm, "Speaker");
500 	snd_soc_dapm_disable_pin(dapm, "AGCIN");
501 	snd_soc_dapm_disable_pin(dapm, "AGCOUT");
502 
503 	return 0;
504 }
505 
506 /* DAI glue - connects codec <--> CPU */
507 SND_SOC_DAILINK_DEFS(cx20442,
508 	DAILINK_COMP_ARRAY(COMP_CPU("omap-mcbsp.1")),
509 	DAILINK_COMP_ARRAY(COMP_CODEC("cx20442-codec", "cx20442-voice")),
510 	DAILINK_COMP_ARRAY(COMP_PLATFORM("omap-mcbsp.1")));
511 
512 static struct snd_soc_dai_link ams_delta_dai_link = {
513 	.name = "CX20442",
514 	.stream_name = "CX20442",
515 	.init = ams_delta_cx20442_init,
516 	.ops = &ams_delta_ops,
517 	.dai_fmt = SND_SOC_DAIFMT_DSP_A | SND_SOC_DAIFMT_NB_NF |
518 		   SND_SOC_DAIFMT_CBM_CFM,
519 	SND_SOC_DAILINK_REG(cx20442),
520 };
521 
522 /* Audio card driver */
523 static struct snd_soc_card ams_delta_audio_card = {
524 	.name = "AMS_DELTA",
525 	.owner = THIS_MODULE,
526 	.dai_link = &ams_delta_dai_link,
527 	.num_links = 1,
528 
529 	.controls = ams_delta_audio_controls,
530 	.num_controls = ARRAY_SIZE(ams_delta_audio_controls),
531 	.dapm_widgets = ams_delta_dapm_widgets,
532 	.num_dapm_widgets = ARRAY_SIZE(ams_delta_dapm_widgets),
533 	.dapm_routes = ams_delta_audio_map,
534 	.num_dapm_routes = ARRAY_SIZE(ams_delta_audio_map),
535 };
536 
537 /* Module init/exit */
538 static int ams_delta_probe(struct platform_device *pdev)
539 {
540 	struct snd_soc_card *card = &ams_delta_audio_card;
541 	int ret;
542 
543 	card->dev = &pdev->dev;
544 
545 	ret = snd_soc_register_card(card);
546 	if (ret) {
547 		dev_err(&pdev->dev, "snd_soc_register_card failed (%d)\n", ret);
548 		card->dev = NULL;
549 		return ret;
550 	}
551 	return 0;
552 }
553 
554 static int ams_delta_remove(struct platform_device *pdev)
555 {
556 	struct snd_soc_card *card = platform_get_drvdata(pdev);
557 
558 	if (tty_unregister_ldisc(N_V253) != 0)
559 		dev_warn(&pdev->dev,
560 			"failed to unregister V253 line discipline\n");
561 
562 	snd_soc_unregister_card(card);
563 	card->dev = NULL;
564 	return 0;
565 }
566 
567 #define DRV_NAME "ams-delta-audio"
568 
569 static struct platform_driver ams_delta_driver = {
570 	.driver = {
571 		.name = DRV_NAME,
572 	},
573 	.probe = ams_delta_probe,
574 	.remove = ams_delta_remove,
575 };
576 
577 module_platform_driver(ams_delta_driver);
578 
579 MODULE_AUTHOR("Janusz Krzysztofik <jkrzyszt@tis.icnet.pl>");
580 MODULE_DESCRIPTION("ALSA SoC driver for Amstrad E3 (Delta) videophone");
581 MODULE_LICENSE("GPL");
582 MODULE_ALIAS("platform:" DRV_NAME);
583