1// SPDX-License-Identifier: GPL-2.0-or-later
2/*
3 * cx20442.c  --  CX20442 ALSA Soc Audio driver
4 *
5 * Copyright 2009 Janusz Krzysztofik <jkrzyszt@tis.icnet.pl>
6 *
7 * Initially based on sound/soc/codecs/wm8400.c
8 * Copyright 2008, 2009 Wolfson Microelectronics PLC.
9 * Author: Mark Brown <broonie@opensource.wolfsonmicro.com>
10 */
11
12#include <linux/tty.h>
13#include <linux/slab.h>
14#include <linux/module.h>
15#include <linux/regulator/consumer.h>
16
17#include <sound/core.h>
18#include <sound/initval.h>
19#include <sound/soc.h>
20
21#include "cx20442.h"
22
23
24struct cx20442_priv {
25	struct tty_struct *tty;
26	struct regulator *por;
27	u8 reg_cache;
28};
29
30#define CX20442_PM		0x0
31
32#define CX20442_TELIN		0
33#define CX20442_TELOUT		1
34#define CX20442_MIC		2
35#define CX20442_SPKOUT		3
36#define CX20442_AGC		4
37
38static const struct snd_soc_dapm_widget cx20442_dapm_widgets[] = {
39	SND_SOC_DAPM_OUTPUT("TELOUT"),
40	SND_SOC_DAPM_OUTPUT("SPKOUT"),
41	SND_SOC_DAPM_OUTPUT("AGCOUT"),
42
43	SND_SOC_DAPM_MIXER("SPKOUT Mixer", SND_SOC_NOPM, 0, 0, NULL, 0),
44
45	SND_SOC_DAPM_PGA("TELOUT Amp", CX20442_PM, CX20442_TELOUT, 0, NULL, 0),
46	SND_SOC_DAPM_PGA("SPKOUT Amp", CX20442_PM, CX20442_SPKOUT, 0, NULL, 0),
47	SND_SOC_DAPM_PGA("SPKOUT AGC", CX20442_PM, CX20442_AGC, 0, NULL, 0),
48
49	SND_SOC_DAPM_DAC("DAC", "Playback", SND_SOC_NOPM, 0, 0),
50	SND_SOC_DAPM_ADC("ADC", "Capture", SND_SOC_NOPM, 0, 0),
51
52	SND_SOC_DAPM_MIXER("Input Mixer", SND_SOC_NOPM, 0, 0, NULL, 0),
53
54	SND_SOC_DAPM_MICBIAS("TELIN Bias", CX20442_PM, CX20442_TELIN, 0),
55	SND_SOC_DAPM_MICBIAS("MIC Bias", CX20442_PM, CX20442_MIC, 0),
56
57	SND_SOC_DAPM_PGA("MIC AGC", CX20442_PM, CX20442_AGC, 0, NULL, 0),
58
59	SND_SOC_DAPM_INPUT("TELIN"),
60	SND_SOC_DAPM_INPUT("MIC"),
61	SND_SOC_DAPM_INPUT("AGCIN"),
62};
63
64static const struct snd_soc_dapm_route cx20442_audio_map[] = {
65	{"TELOUT", NULL, "TELOUT Amp"},
66
67	{"SPKOUT", NULL, "SPKOUT Mixer"},
68	{"SPKOUT Mixer", NULL, "SPKOUT Amp"},
69
70	{"TELOUT Amp", NULL, "DAC"},
71	{"SPKOUT Amp", NULL, "DAC"},
72
73	{"SPKOUT Mixer", NULL, "SPKOUT AGC"},
74	{"SPKOUT AGC", NULL, "AGCIN"},
75
76	{"AGCOUT", NULL, "MIC AGC"},
77	{"MIC AGC", NULL, "MIC"},
78
79	{"MIC Bias", NULL, "MIC"},
80	{"Input Mixer", NULL, "MIC Bias"},
81
82	{"TELIN Bias", NULL, "TELIN"},
83	{"Input Mixer", NULL, "TELIN Bias"},
84
85	{"ADC", NULL, "Input Mixer"},
86};
87
88static unsigned int cx20442_read_reg_cache(struct snd_soc_component *component,
89					   unsigned int reg)
90{
91	struct cx20442_priv *cx20442 = snd_soc_component_get_drvdata(component);
92
93	if (reg >= 1)
94		return -EINVAL;
95
96	return cx20442->reg_cache;
97}
98
99enum v253_vls {
100	V253_VLS_NONE = 0,
101	V253_VLS_T,
102	V253_VLS_L,
103	V253_VLS_LT,
104	V253_VLS_S,
105	V253_VLS_ST,
106	V253_VLS_M,
107	V253_VLS_MST,
108	V253_VLS_S1,
109	V253_VLS_S1T,
110	V253_VLS_MS1T,
111	V253_VLS_M1,
112	V253_VLS_M1ST,
113	V253_VLS_M1S1T,
114	V253_VLS_H,
115	V253_VLS_HT,
116	V253_VLS_MS,
117	V253_VLS_MS1,
118	V253_VLS_M1S,
119	V253_VLS_M1S1,
120	V253_VLS_TEST,
121};
122
123static int cx20442_pm_to_v253_vls(u8 value)
124{
125	switch (value & ~(1 << CX20442_AGC)) {
126	case 0:
127		return V253_VLS_T;
128	case (1 << CX20442_SPKOUT):
129	case (1 << CX20442_MIC):
130	case (1 << CX20442_SPKOUT) | (1 << CX20442_MIC):
131		return V253_VLS_M1S1;
132	case (1 << CX20442_TELOUT):
133	case (1 << CX20442_TELIN):
134	case (1 << CX20442_TELOUT) | (1 << CX20442_TELIN):
135		return V253_VLS_L;
136	case (1 << CX20442_TELOUT) | (1 << CX20442_MIC):
137		return V253_VLS_NONE;
138	}
139	return -EINVAL;
140}
141static int cx20442_pm_to_v253_vsp(u8 value)
142{
143	switch (value & ~(1 << CX20442_AGC)) {
144	case (1 << CX20442_SPKOUT):
145	case (1 << CX20442_MIC):
146	case (1 << CX20442_SPKOUT) | (1 << CX20442_MIC):
147		return (bool)(value & (1 << CX20442_AGC));
148	}
149	return (value & (1 << CX20442_AGC)) ? -EINVAL : 0;
150}
151
152static int cx20442_write(struct snd_soc_component *component, unsigned int reg,
153							unsigned int value)
154{
155	struct cx20442_priv *cx20442 = snd_soc_component_get_drvdata(component);
156	int vls, vsp, old, len;
157	char buf[18];
158
159	if (reg >= 1)
160		return -EINVAL;
161
162	/* tty and write pointers required for talking to the modem
163	 * are expected to be set by the line discipline initialization code */
164	if (!cx20442->tty || !cx20442->tty->ops->write)
165		return -EIO;
166
167	old = cx20442->reg_cache;
168	cx20442->reg_cache = value;
169
170	vls = cx20442_pm_to_v253_vls(value);
171	if (vls < 0)
172		return vls;
173
174	vsp = cx20442_pm_to_v253_vsp(value);
175	if (vsp < 0)
176		return vsp;
177
178	if ((vls == V253_VLS_T) ||
179			(vls == cx20442_pm_to_v253_vls(old))) {
180		if (vsp == cx20442_pm_to_v253_vsp(old))
181			return 0;
182		len = snprintf(buf, ARRAY_SIZE(buf), "at+vsp=%d\r", vsp);
183	} else if (vsp == cx20442_pm_to_v253_vsp(old))
184		len = snprintf(buf, ARRAY_SIZE(buf), "at+vls=%d\r", vls);
185	else
186		len = snprintf(buf, ARRAY_SIZE(buf),
187					"at+vls=%d;+vsp=%d\r", vls, vsp);
188
189	if (unlikely(len > (ARRAY_SIZE(buf) - 1)))
190		return -ENOMEM;
191
192	dev_dbg(component->dev, "%s: %s\n", __func__, buf);
193	if (cx20442->tty->ops->write(cx20442->tty, buf, len) != len)
194		return -EIO;
195
196	return 0;
197}
198
199/*
200 * Line discpline related code
201 *
202 * Any of the callback functions below can be used in two ways:
203 * 1) registerd by a machine driver as one of line discipline operations,
204 * 2) called from a machine's provided line discipline callback function
205 *    in case when extra machine specific code must be run as well.
206 */
207
208/* Modem init: echo off, digital speaker off, quiet off, voice mode */
209static const char v253_init[] = "ate0m0q0+fclass=8\r";
210
211/* Line discipline .open() */
212static int v253_open(struct tty_struct *tty)
213{
214	int ret, len = strlen(v253_init);
215
216	/* Doesn't make sense without write callback */
217	if (!tty->ops->write)
218		return -EINVAL;
219
220	/* Won't work if no codec pointer has been passed by a card driver */
221	if (!tty->disc_data)
222		return -ENODEV;
223
224	tty->receive_room = 16;
225	if (tty->ops->write(tty, v253_init, len) != len) {
226		ret = -EIO;
227		goto err;
228	}
229	/* Actual setup will be performed after the modem responds. */
230	return 0;
231err:
232	tty->disc_data = NULL;
233	return ret;
234}
235
236/* Line discipline .close() */
237static void v253_close(struct tty_struct *tty)
238{
239	struct snd_soc_component *component = tty->disc_data;
240	struct cx20442_priv *cx20442;
241
242	tty->disc_data = NULL;
243
244	if (!component)
245		return;
246
247	cx20442 = snd_soc_component_get_drvdata(component);
248
249	/* Prevent the codec driver from further accessing the modem */
250	cx20442->tty = NULL;
251	component->card->pop_time = 0;
252}
253
254/* Line discipline .hangup() */
255static void v253_hangup(struct tty_struct *tty)
256{
257	v253_close(tty);
258}
259
260/* Line discipline .receive_buf() */
261static void v253_receive(struct tty_struct *tty, const u8 *cp, const u8 *fp,
262			 size_t count)
263{
264	struct snd_soc_component *component = tty->disc_data;
265	struct cx20442_priv *cx20442;
266
267	if (!component)
268		return;
269
270	cx20442 = snd_soc_component_get_drvdata(component);
271
272	if (!cx20442->tty) {
273		/* First modem response, complete setup procedure */
274
275		/* Set up codec driver access to modem controls */
276		cx20442->tty = tty;
277		component->card->pop_time = 1;
278	}
279}
280
281struct tty_ldisc_ops v253_ops = {
282	.name = "cx20442",
283	.owner = THIS_MODULE,
284	.open = v253_open,
285	.close = v253_close,
286	.hangup = v253_hangup,
287	.receive_buf = v253_receive,
288};
289EXPORT_SYMBOL_GPL(v253_ops);
290
291
292/*
293 * Codec DAI
294 */
295
296static struct snd_soc_dai_driver cx20442_dai = {
297	.name = "cx20442-voice",
298	.playback = {
299		.stream_name = "Playback",
300		.channels_min = 1,
301		.channels_max = 1,
302		.rates = SNDRV_PCM_RATE_8000,
303		.formats = SNDRV_PCM_FMTBIT_S16_LE,
304	},
305	.capture = {
306		.stream_name = "Capture",
307		.channels_min = 1,
308		.channels_max = 1,
309		.rates = SNDRV_PCM_RATE_8000,
310		.formats = SNDRV_PCM_FMTBIT_S16_LE,
311	},
312};
313
314static int cx20442_set_bias_level(struct snd_soc_component *component,
315		enum snd_soc_bias_level level)
316{
317	struct cx20442_priv *cx20442 = snd_soc_component_get_drvdata(component);
318	int err = 0;
319
320	switch (level) {
321	case SND_SOC_BIAS_PREPARE:
322		if (snd_soc_component_get_bias_level(component) != SND_SOC_BIAS_STANDBY)
323			break;
324		if (IS_ERR(cx20442->por))
325			err = PTR_ERR(cx20442->por);
326		else
327			err = regulator_enable(cx20442->por);
328		break;
329	case SND_SOC_BIAS_STANDBY:
330		if (snd_soc_component_get_bias_level(component) != SND_SOC_BIAS_PREPARE)
331			break;
332		if (IS_ERR(cx20442->por))
333			err = PTR_ERR(cx20442->por);
334		else
335			err = regulator_disable(cx20442->por);
336		break;
337	default:
338		break;
339	}
340
341	return err;
342}
343
344static int cx20442_component_probe(struct snd_soc_component *component)
345{
346	struct cx20442_priv *cx20442;
347
348	cx20442 = kzalloc(sizeof(struct cx20442_priv), GFP_KERNEL);
349	if (cx20442 == NULL)
350		return -ENOMEM;
351
352	cx20442->por = regulator_get(component->dev, "POR");
353	if (IS_ERR(cx20442->por)) {
354		int err = PTR_ERR(cx20442->por);
355
356		dev_warn(component->dev, "failed to get POR supply (%d)", err);
357		/*
358		 * When running on a non-dt platform and requested regulator
359		 * is not available, regulator_get() never returns
360		 * -EPROBE_DEFER as it is not able to justify if the regulator
361		 * may still appear later.  On the other hand, the board can
362		 * still set full constraints flag at late_initcall in order
363		 * to instruct regulator_get() to return a dummy one if
364		 * sufficient.  Hence, if we get -ENODEV here, let's convert
365		 * it to -EPROBE_DEFER and wait for the board to decide or
366		 * let Deferred Probe infrastructure handle this error.
367		 */
368		if (err == -ENODEV)
369			err = -EPROBE_DEFER;
370		kfree(cx20442);
371		return err;
372	}
373
374	cx20442->tty = NULL;
375
376	snd_soc_component_set_drvdata(component, cx20442);
377	component->card->pop_time = 0;
378
379	return 0;
380}
381
382/* power down chip */
383static void cx20442_component_remove(struct snd_soc_component *component)
384{
385	struct cx20442_priv *cx20442 = snd_soc_component_get_drvdata(component);
386
387	if (cx20442->tty) {
388		struct tty_struct *tty = cx20442->tty;
389		tty_hangup(tty);
390	}
391
392	if (!IS_ERR(cx20442->por)) {
393		/* should be already in STANDBY, hence disabled */
394		regulator_put(cx20442->por);
395	}
396
397	snd_soc_component_set_drvdata(component, NULL);
398	kfree(cx20442);
399}
400
401static const struct snd_soc_component_driver cx20442_component_dev = {
402	.probe			= cx20442_component_probe,
403	.remove			= cx20442_component_remove,
404	.set_bias_level		= cx20442_set_bias_level,
405	.read			= cx20442_read_reg_cache,
406	.write			= cx20442_write,
407	.dapm_widgets		= cx20442_dapm_widgets,
408	.num_dapm_widgets	= ARRAY_SIZE(cx20442_dapm_widgets),
409	.dapm_routes		= cx20442_audio_map,
410	.num_dapm_routes	= ARRAY_SIZE(cx20442_audio_map),
411	.idle_bias_on		= 1,
412	.use_pmdown_time	= 1,
413	.endianness		= 1,
414};
415
416static int cx20442_platform_probe(struct platform_device *pdev)
417{
418	return devm_snd_soc_register_component(&pdev->dev,
419			&cx20442_component_dev, &cx20442_dai, 1);
420}
421
422static struct platform_driver cx20442_platform_driver = {
423	.driver = {
424		.name = "cx20442-codec",
425		},
426	.probe = cx20442_platform_probe,
427};
428
429module_platform_driver(cx20442_platform_driver);
430
431MODULE_DESCRIPTION("ASoC CX20442-11 voice modem codec driver");
432MODULE_AUTHOR("Janusz Krzysztofik");
433MODULE_LICENSE("GPL");
434MODULE_ALIAS("platform:cx20442-codec");
435