1/*
2 * TS3A227E Autonomous Audio Accessory Detection and Configuration Switch
3 *
4 * Copyright (C) 2014 Google, Inc.
5 *
6 * This program is free software; you can redistribute it and/or modify
7 * it under the terms of the GNU General Public License version 2 as
8 * published by the Free Software Foundation.
9 */
10
11#include <linux/gpio.h>
12#include <linux/i2c.h>
13#include <linux/init.h>
14#include <linux/input.h>
15#include <linux/module.h>
16#include <linux/of_gpio.h>
17#include <linux/regmap.h>
18
19#include <sound/core.h>
20#include <sound/jack.h>
21#include <sound/soc.h>
22
23#include "ts3a227e.h"
24
25struct ts3a227e {
26	struct regmap *regmap;
27	struct snd_soc_jack *jack;
28	bool plugged;
29	bool mic_present;
30	unsigned int buttons_held;
31};
32
33/* Button values to be reported on the jack */
34static const int ts3a227e_buttons[] = {
35	SND_JACK_BTN_0,
36	SND_JACK_BTN_1,
37	SND_JACK_BTN_2,
38	SND_JACK_BTN_3,
39};
40
41#define TS3A227E_NUM_BUTTONS 4
42#define TS3A227E_JACK_MASK (SND_JACK_HEADPHONE | \
43			    SND_JACK_MICROPHONE | \
44			    SND_JACK_BTN_0 | \
45			    SND_JACK_BTN_1 | \
46			    SND_JACK_BTN_2 | \
47			    SND_JACK_BTN_3)
48
49/* TS3A227E registers */
50#define TS3A227E_REG_DEVICE_ID		0x00
51#define TS3A227E_REG_INTERRUPT		0x01
52#define TS3A227E_REG_KP_INTERRUPT	0x02
53#define TS3A227E_REG_INTERRUPT_DISABLE	0x03
54#define TS3A227E_REG_SETTING_1		0x04
55#define TS3A227E_REG_SETTING_2		0x05
56#define TS3A227E_REG_SETTING_3		0x06
57#define TS3A227E_REG_SWITCH_CONTROL_1	0x07
58#define TS3A227E_REG_SWITCH_CONTROL_2	0x08
59#define TS3A227E_REG_SWITCH_STATUS_1	0x09
60#define TS3A227E_REG_SWITCH_STATUS_2	0x0a
61#define TS3A227E_REG_ACCESSORY_STATUS	0x0b
62#define TS3A227E_REG_ADC_OUTPUT		0x0c
63#define TS3A227E_REG_KP_THRESHOLD_1	0x0d
64#define TS3A227E_REG_KP_THRESHOLD_2	0x0e
65#define TS3A227E_REG_KP_THRESHOLD_3	0x0f
66
67/* TS3A227E_REG_INTERRUPT 0x01 */
68#define INS_REM_EVENT 0x01
69#define DETECTION_COMPLETE_EVENT 0x02
70
71/* TS3A227E_REG_KP_INTERRUPT 0x02 */
72#define PRESS_MASK(idx) (0x01 << (2 * (idx)))
73#define RELEASE_MASK(idx) (0x02 << (2 * (idx)))
74
75/* TS3A227E_REG_INTERRUPT_DISABLE 0x03 */
76#define INS_REM_INT_DISABLE 0x01
77#define DETECTION_COMPLETE_INT_DISABLE 0x02
78#define ADC_COMPLETE_INT_DISABLE 0x04
79#define INTB_DISABLE 0x08
80
81/* TS3A227E_REG_SETTING_2 0x05 */
82#define KP_ENABLE 0x04
83
84/* TS3A227E_REG_SETTING_3 0x06 */
85#define MICBIAS_SETTING_SFT (3)
86#define MICBIAS_SETTING_MASK (0x7 << MICBIAS_SETTING_SFT)
87
88/* TS3A227E_REG_ACCESSORY_STATUS  0x0b */
89#define TYPE_3_POLE 0x01
90#define TYPE_4_POLE_OMTP 0x02
91#define TYPE_4_POLE_STANDARD 0x04
92#define JACK_INSERTED 0x08
93#define EITHER_MIC_MASK (TYPE_4_POLE_OMTP | TYPE_4_POLE_STANDARD)
94
95static const struct reg_default ts3a227e_reg_defaults[] = {
96	{ TS3A227E_REG_DEVICE_ID, 0x10 },
97	{ TS3A227E_REG_INTERRUPT, 0x00 },
98	{ TS3A227E_REG_KP_INTERRUPT, 0x00 },
99	{ TS3A227E_REG_INTERRUPT_DISABLE, 0x08 },
100	{ TS3A227E_REG_SETTING_1, 0x23 },
101	{ TS3A227E_REG_SETTING_2, 0x00 },
102	{ TS3A227E_REG_SETTING_3, 0x0e },
103	{ TS3A227E_REG_SWITCH_CONTROL_1, 0x00 },
104	{ TS3A227E_REG_SWITCH_CONTROL_2, 0x00 },
105	{ TS3A227E_REG_SWITCH_STATUS_1, 0x0c },
106	{ TS3A227E_REG_SWITCH_STATUS_2, 0x00 },
107	{ TS3A227E_REG_ACCESSORY_STATUS, 0x00 },
108	{ TS3A227E_REG_ADC_OUTPUT, 0x00 },
109	{ TS3A227E_REG_KP_THRESHOLD_1, 0x20 },
110	{ TS3A227E_REG_KP_THRESHOLD_2, 0x40 },
111	{ TS3A227E_REG_KP_THRESHOLD_3, 0x68 },
112};
113
114static bool ts3a227e_readable_reg(struct device *dev, unsigned int reg)
115{
116	switch (reg) {
117	case TS3A227E_REG_DEVICE_ID ... TS3A227E_REG_KP_THRESHOLD_3:
118		return true;
119	default:
120		return false;
121	}
122}
123
124static bool ts3a227e_writeable_reg(struct device *dev, unsigned int reg)
125{
126	switch (reg) {
127	case TS3A227E_REG_INTERRUPT_DISABLE ... TS3A227E_REG_SWITCH_CONTROL_2:
128	case TS3A227E_REG_KP_THRESHOLD_1 ... TS3A227E_REG_KP_THRESHOLD_3:
129		return true;
130	default:
131		return false;
132	}
133}
134
135static bool ts3a227e_volatile_reg(struct device *dev, unsigned int reg)
136{
137	switch (reg) {
138	case TS3A227E_REG_INTERRUPT ... TS3A227E_REG_INTERRUPT_DISABLE:
139	case TS3A227E_REG_SETTING_2:
140	case TS3A227E_REG_SWITCH_STATUS_1 ... TS3A227E_REG_ADC_OUTPUT:
141		return true;
142	default:
143		return false;
144	}
145}
146
147static void ts3a227e_jack_report(struct ts3a227e *ts3a227e)
148{
149	unsigned int i;
150	int report = 0;
151
152	if (!ts3a227e->jack)
153		return;
154
155	if (ts3a227e->plugged)
156		report = SND_JACK_HEADPHONE;
157	if (ts3a227e->mic_present)
158		report |= SND_JACK_MICROPHONE;
159	for (i = 0; i < TS3A227E_NUM_BUTTONS; i++) {
160		if (ts3a227e->buttons_held & (1 << i))
161			report |= ts3a227e_buttons[i];
162	}
163	snd_soc_jack_report(ts3a227e->jack, report, TS3A227E_JACK_MASK);
164}
165
166static void ts3a227e_new_jack_state(struct ts3a227e *ts3a227e, unsigned acc_reg)
167{
168	bool plugged, mic_present;
169
170	plugged = !!(acc_reg & JACK_INSERTED);
171	mic_present = plugged && !!(acc_reg & EITHER_MIC_MASK);
172
173	ts3a227e->plugged = plugged;
174
175	if (mic_present != ts3a227e->mic_present) {
176		ts3a227e->mic_present = mic_present;
177		ts3a227e->buttons_held = 0;
178		if (mic_present) {
179			/* Enable key press detection. */
180			regmap_update_bits(ts3a227e->regmap,
181					   TS3A227E_REG_SETTING_2,
182					   KP_ENABLE, KP_ENABLE);
183		}
184	}
185}
186
187static irqreturn_t ts3a227e_interrupt(int irq, void *data)
188{
189	struct ts3a227e *ts3a227e = (struct ts3a227e *)data;
190	struct regmap *regmap = ts3a227e->regmap;
191	unsigned int int_reg, kp_int_reg, acc_reg, i;
192
193	/* Check for plug/unplug. */
194	regmap_read(regmap, TS3A227E_REG_INTERRUPT, &int_reg);
195	if (int_reg & (DETECTION_COMPLETE_EVENT | INS_REM_EVENT)) {
196		regmap_read(regmap, TS3A227E_REG_ACCESSORY_STATUS, &acc_reg);
197		ts3a227e_new_jack_state(ts3a227e, acc_reg);
198	}
199
200	/* Report any key events. */
201	regmap_read(regmap, TS3A227E_REG_KP_INTERRUPT, &kp_int_reg);
202	for (i = 0; i < TS3A227E_NUM_BUTTONS; i++) {
203		if (kp_int_reg & PRESS_MASK(i))
204			ts3a227e->buttons_held |= (1 << i);
205		if (kp_int_reg & RELEASE_MASK(i))
206			ts3a227e->buttons_held &= ~(1 << i);
207	}
208
209	ts3a227e_jack_report(ts3a227e);
210
211	return IRQ_HANDLED;
212}
213
214/**
215 * ts3a227e_enable_jack_detect - Specify a jack for event reporting
216 *
217 * @component:  component to register the jack with
218 * @jack: jack to use to report headset and button events on
219 *
220 * After this function has been called the headset insert/remove and button
221 * events 0-3 will be routed to the given jack.  Jack can be null to stop
222 * reporting.
223 */
224int ts3a227e_enable_jack_detect(struct snd_soc_component *component,
225				struct snd_soc_jack *jack)
226{
227	struct ts3a227e *ts3a227e = snd_soc_component_get_drvdata(component);
228
229	snd_jack_set_key(jack->jack, SND_JACK_BTN_0, KEY_MEDIA);
230	snd_jack_set_key(jack->jack, SND_JACK_BTN_1, KEY_VOICECOMMAND);
231	snd_jack_set_key(jack->jack, SND_JACK_BTN_2, KEY_VOLUMEUP);
232	snd_jack_set_key(jack->jack, SND_JACK_BTN_3, KEY_VOLUMEDOWN);
233
234	ts3a227e->jack = jack;
235	ts3a227e_jack_report(ts3a227e);
236
237	return 0;
238}
239EXPORT_SYMBOL_GPL(ts3a227e_enable_jack_detect);
240
241static struct snd_soc_component_driver ts3a227e_soc_driver;
242
243static const struct regmap_config ts3a227e_regmap_config = {
244	.val_bits = 8,
245	.reg_bits = 8,
246
247	.max_register = TS3A227E_REG_KP_THRESHOLD_3,
248	.readable_reg = ts3a227e_readable_reg,
249	.writeable_reg = ts3a227e_writeable_reg,
250	.volatile_reg = ts3a227e_volatile_reg,
251
252	.cache_type = REGCACHE_RBTREE,
253	.reg_defaults = ts3a227e_reg_defaults,
254	.num_reg_defaults = ARRAY_SIZE(ts3a227e_reg_defaults),
255};
256
257static int ts3a227e_parse_dt(struct ts3a227e *ts3a227e, struct device_node *np)
258{
259	u32 micbias;
260	int err;
261
262	err = of_property_read_u32(np, "ti,micbias", &micbias);
263	if (!err) {
264		regmap_update_bits(ts3a227e->regmap, TS3A227E_REG_SETTING_3,
265			MICBIAS_SETTING_MASK,
266			(micbias & 0x07) << MICBIAS_SETTING_SFT);
267	}
268
269	return 0;
270}
271
272static int ts3a227e_i2c_probe(struct i2c_client *i2c,
273			      const struct i2c_device_id *id)
274{
275	struct ts3a227e *ts3a227e;
276	struct device *dev = &i2c->dev;
277	int ret;
278	unsigned int acc_reg;
279
280	ts3a227e = devm_kzalloc(&i2c->dev, sizeof(*ts3a227e), GFP_KERNEL);
281	if (ts3a227e == NULL)
282		return -ENOMEM;
283
284	i2c_set_clientdata(i2c, ts3a227e);
285
286	ts3a227e->regmap = devm_regmap_init_i2c(i2c, &ts3a227e_regmap_config);
287	if (IS_ERR(ts3a227e->regmap))
288		return PTR_ERR(ts3a227e->regmap);
289
290	if (dev->of_node) {
291		ret = ts3a227e_parse_dt(ts3a227e, dev->of_node);
292		if (ret) {
293			dev_err(dev, "Failed to parse device tree: %d\n", ret);
294			return ret;
295		}
296	}
297
298	ret = devm_request_threaded_irq(dev, i2c->irq, NULL, ts3a227e_interrupt,
299					IRQF_TRIGGER_LOW | IRQF_ONESHOT,
300					"TS3A227E", ts3a227e);
301	if (ret) {
302		dev_err(dev, "Cannot request irq %d (%d)\n", i2c->irq, ret);
303		return ret;
304	}
305
306	ret = devm_snd_soc_register_component(&i2c->dev, &ts3a227e_soc_driver,
307					      NULL, 0);
308	if (ret)
309		return ret;
310
311	/* Enable interrupts except for ADC complete. */
312	regmap_update_bits(ts3a227e->regmap, TS3A227E_REG_INTERRUPT_DISABLE,
313			   INTB_DISABLE | ADC_COMPLETE_INT_DISABLE,
314			   ADC_COMPLETE_INT_DISABLE);
315
316	/* Read jack status because chip might not trigger interrupt at boot. */
317	regmap_read(ts3a227e->regmap, TS3A227E_REG_ACCESSORY_STATUS, &acc_reg);
318	ts3a227e_new_jack_state(ts3a227e, acc_reg);
319	ts3a227e_jack_report(ts3a227e);
320
321	return 0;
322}
323
324static const struct i2c_device_id ts3a227e_i2c_ids[] = {
325	{ "ts3a227e", 0 },
326	{ }
327};
328MODULE_DEVICE_TABLE(i2c, ts3a227e_i2c_ids);
329
330static const struct of_device_id ts3a227e_of_match[] = {
331	{ .compatible = "ti,ts3a227e", },
332	{ }
333};
334MODULE_DEVICE_TABLE(of, ts3a227e_of_match);
335
336static struct i2c_driver ts3a227e_driver = {
337	.driver = {
338		.name = "ts3a227e",
339		.owner = THIS_MODULE,
340		.of_match_table = of_match_ptr(ts3a227e_of_match),
341	},
342	.probe = ts3a227e_i2c_probe,
343	.id_table = ts3a227e_i2c_ids,
344};
345module_i2c_driver(ts3a227e_driver);
346
347MODULE_DESCRIPTION("ASoC ts3a227e driver");
348MODULE_AUTHOR("Dylan Reid <dgreid@chromium.org>");
349MODULE_LICENSE("GPL v2");
350