1// SPDX-License-Identifier: GPL-2.0-only
2/*
3 * Regulator driver for National Semiconductors LP3971 PMIC chip
4 *
5 *  Copyright (C) 2009 Samsung Electronics
6 *  Author: Marek Szyprowski <m.szyprowski@samsung.com>
7 *
8 * Based on wm8350.c
9 */
10
11#include <linux/bug.h>
12#include <linux/err.h>
13#include <linux/i2c.h>
14#include <linux/kernel.h>
15#include <linux/module.h>
16#include <linux/regulator/driver.h>
17#include <linux/regulator/lp3971.h>
18#include <linux/slab.h>
19
20struct lp3971 {
21	struct device *dev;
22	struct mutex io_lock;
23	struct i2c_client *i2c;
24};
25
26static u8 lp3971_reg_read(struct lp3971 *lp3971, u8 reg);
27static int lp3971_set_bits(struct lp3971 *lp3971, u8 reg, u16 mask, u16 val);
28
29#define LP3971_SYS_CONTROL1_REG 0x07
30
31/* System control register 1 initial value,
32   bits 4 and 5 are EPROM programmable */
33#define SYS_CONTROL1_INIT_VAL 0x40
34#define SYS_CONTROL1_INIT_MASK 0xCF
35
36#define LP3971_BUCK_VOL_ENABLE_REG 0x10
37#define LP3971_BUCK_VOL_CHANGE_REG 0x20
38
39/*	Voltage control registers shift:
40	LP3971_BUCK1 -> 0
41	LP3971_BUCK2 -> 4
42	LP3971_BUCK3 -> 6
43*/
44#define BUCK_VOL_CHANGE_SHIFT(x) (((!!x) << 2) | (x & ~0x01))
45#define BUCK_VOL_CHANGE_FLAG_GO 0x01
46#define BUCK_VOL_CHANGE_FLAG_TARGET 0x02
47#define BUCK_VOL_CHANGE_FLAG_MASK 0x03
48
49#define LP3971_BUCK1_BASE 0x23
50#define LP3971_BUCK2_BASE 0x29
51#define LP3971_BUCK3_BASE 0x32
52
53static const int buck_base_addr[] = {
54	LP3971_BUCK1_BASE,
55	LP3971_BUCK2_BASE,
56	LP3971_BUCK3_BASE,
57};
58
59#define LP3971_BUCK_TARGET_VOL1_REG(x) (buck_base_addr[x])
60#define LP3971_BUCK_TARGET_VOL2_REG(x) (buck_base_addr[x]+1)
61
62static const unsigned int buck_voltage_map[] = {
63	      0,  800000,  850000,  900000,  950000, 1000000, 1050000, 1100000,
64	1150000, 1200000, 1250000, 1300000, 1350000, 1400000, 1450000, 1500000,
65	1550000, 1600000, 1650000, 1700000, 1800000, 1900000, 2500000, 2800000,
66	3000000, 3300000,
67};
68
69#define BUCK_TARGET_VOL_MASK 0x3f
70
71#define LP3971_BUCK_RAMP_REG(x)	(buck_base_addr[x]+2)
72
73#define LP3971_LDO_ENABLE_REG 0x12
74#define LP3971_LDO_VOL_CONTR_BASE 0x39
75
76/*	Voltage control registers:
77	LP3971_LDO1 -> LP3971_LDO_VOL_CONTR_BASE + 0
78	LP3971_LDO2 -> LP3971_LDO_VOL_CONTR_BASE + 0
79	LP3971_LDO3 -> LP3971_LDO_VOL_CONTR_BASE + 1
80	LP3971_LDO4 -> LP3971_LDO_VOL_CONTR_BASE + 1
81	LP3971_LDO5 -> LP3971_LDO_VOL_CONTR_BASE + 2
82*/
83#define LP3971_LDO_VOL_CONTR_REG(x)	(LP3971_LDO_VOL_CONTR_BASE + (x >> 1))
84
85/*	Voltage control registers shift:
86	LP3971_LDO1 -> 0, LP3971_LDO2 -> 4
87	LP3971_LDO3 -> 0, LP3971_LDO4 -> 4
88	LP3971_LDO5 -> 0
89*/
90#define LDO_VOL_CONTR_SHIFT(x) ((x & 1) << 2)
91#define LDO_VOL_CONTR_MASK 0x0f
92
93static const unsigned int ldo45_voltage_map[] = {
94	1000000, 1050000, 1100000, 1150000, 1200000, 1250000, 1300000, 1350000,
95	1400000, 1500000, 1800000, 1900000, 2500000, 2800000, 3000000, 3300000,
96};
97
98static const unsigned int ldo123_voltage_map[] = {
99	1800000, 1900000, 2000000, 2100000, 2200000, 2300000, 2400000, 2500000,
100	2600000, 2700000, 2800000, 2900000, 3000000, 3100000, 3200000, 3300000,
101};
102
103#define LDO_VOL_MIN_IDX 0x00
104#define LDO_VOL_MAX_IDX 0x0f
105
106static int lp3971_ldo_is_enabled(struct regulator_dev *dev)
107{
108	struct lp3971 *lp3971 = rdev_get_drvdata(dev);
109	int ldo = rdev_get_id(dev) - LP3971_LDO1;
110	u16 mask = 1 << (1 + ldo);
111	u16 val;
112
113	val = lp3971_reg_read(lp3971, LP3971_LDO_ENABLE_REG);
114	return (val & mask) != 0;
115}
116
117static int lp3971_ldo_enable(struct regulator_dev *dev)
118{
119	struct lp3971 *lp3971 = rdev_get_drvdata(dev);
120	int ldo = rdev_get_id(dev) - LP3971_LDO1;
121	u16 mask = 1 << (1 + ldo);
122
123	return lp3971_set_bits(lp3971, LP3971_LDO_ENABLE_REG, mask, mask);
124}
125
126static int lp3971_ldo_disable(struct regulator_dev *dev)
127{
128	struct lp3971 *lp3971 = rdev_get_drvdata(dev);
129	int ldo = rdev_get_id(dev) - LP3971_LDO1;
130	u16 mask = 1 << (1 + ldo);
131
132	return lp3971_set_bits(lp3971, LP3971_LDO_ENABLE_REG, mask, 0);
133}
134
135static int lp3971_ldo_get_voltage_sel(struct regulator_dev *dev)
136{
137	struct lp3971 *lp3971 = rdev_get_drvdata(dev);
138	int ldo = rdev_get_id(dev) - LP3971_LDO1;
139	u16 val, reg;
140
141	reg = lp3971_reg_read(lp3971, LP3971_LDO_VOL_CONTR_REG(ldo));
142	val = (reg >> LDO_VOL_CONTR_SHIFT(ldo)) & LDO_VOL_CONTR_MASK;
143
144	return val;
145}
146
147static int lp3971_ldo_set_voltage_sel(struct regulator_dev *dev,
148				      unsigned int selector)
149{
150	struct lp3971 *lp3971 = rdev_get_drvdata(dev);
151	int ldo = rdev_get_id(dev) - LP3971_LDO1;
152
153	return lp3971_set_bits(lp3971, LP3971_LDO_VOL_CONTR_REG(ldo),
154			LDO_VOL_CONTR_MASK << LDO_VOL_CONTR_SHIFT(ldo),
155			selector << LDO_VOL_CONTR_SHIFT(ldo));
156}
157
158static const struct regulator_ops lp3971_ldo_ops = {
159	.list_voltage = regulator_list_voltage_table,
160	.map_voltage = regulator_map_voltage_ascend,
161	.is_enabled = lp3971_ldo_is_enabled,
162	.enable = lp3971_ldo_enable,
163	.disable = lp3971_ldo_disable,
164	.get_voltage_sel = lp3971_ldo_get_voltage_sel,
165	.set_voltage_sel = lp3971_ldo_set_voltage_sel,
166};
167
168static int lp3971_dcdc_is_enabled(struct regulator_dev *dev)
169{
170	struct lp3971 *lp3971 = rdev_get_drvdata(dev);
171	int buck = rdev_get_id(dev) - LP3971_DCDC1;
172	u16 mask = 1 << (buck * 2);
173	u16 val;
174
175	val = lp3971_reg_read(lp3971, LP3971_BUCK_VOL_ENABLE_REG);
176	return (val & mask) != 0;
177}
178
179static int lp3971_dcdc_enable(struct regulator_dev *dev)
180{
181	struct lp3971 *lp3971 = rdev_get_drvdata(dev);
182	int buck = rdev_get_id(dev) - LP3971_DCDC1;
183	u16 mask = 1 << (buck * 2);
184
185	return lp3971_set_bits(lp3971, LP3971_BUCK_VOL_ENABLE_REG, mask, mask);
186}
187
188static int lp3971_dcdc_disable(struct regulator_dev *dev)
189{
190	struct lp3971 *lp3971 = rdev_get_drvdata(dev);
191	int buck = rdev_get_id(dev) - LP3971_DCDC1;
192	u16 mask = 1 << (buck * 2);
193
194	return lp3971_set_bits(lp3971, LP3971_BUCK_VOL_ENABLE_REG, mask, 0);
195}
196
197static int lp3971_dcdc_get_voltage_sel(struct regulator_dev *dev)
198{
199	struct lp3971 *lp3971 = rdev_get_drvdata(dev);
200	int buck = rdev_get_id(dev) - LP3971_DCDC1;
201	u16 reg;
202
203	reg = lp3971_reg_read(lp3971, LP3971_BUCK_TARGET_VOL1_REG(buck));
204	reg &= BUCK_TARGET_VOL_MASK;
205
206	return reg;
207}
208
209static int lp3971_dcdc_set_voltage_sel(struct regulator_dev *dev,
210				       unsigned int selector)
211{
212	struct lp3971 *lp3971 = rdev_get_drvdata(dev);
213	int buck = rdev_get_id(dev) - LP3971_DCDC1;
214	int ret;
215
216	ret = lp3971_set_bits(lp3971, LP3971_BUCK_TARGET_VOL1_REG(buck),
217	       BUCK_TARGET_VOL_MASK, selector);
218	if (ret)
219		return ret;
220
221	ret = lp3971_set_bits(lp3971, LP3971_BUCK_VOL_CHANGE_REG,
222	       BUCK_VOL_CHANGE_FLAG_MASK << BUCK_VOL_CHANGE_SHIFT(buck),
223	       BUCK_VOL_CHANGE_FLAG_GO << BUCK_VOL_CHANGE_SHIFT(buck));
224	if (ret)
225		return ret;
226
227	return lp3971_set_bits(lp3971, LP3971_BUCK_VOL_CHANGE_REG,
228	       BUCK_VOL_CHANGE_FLAG_MASK << BUCK_VOL_CHANGE_SHIFT(buck),
229	       0 << BUCK_VOL_CHANGE_SHIFT(buck));
230}
231
232static const struct regulator_ops lp3971_dcdc_ops = {
233	.list_voltage = regulator_list_voltage_table,
234	.map_voltage = regulator_map_voltage_ascend,
235	.is_enabled = lp3971_dcdc_is_enabled,
236	.enable = lp3971_dcdc_enable,
237	.disable = lp3971_dcdc_disable,
238	.get_voltage_sel = lp3971_dcdc_get_voltage_sel,
239	.set_voltage_sel = lp3971_dcdc_set_voltage_sel,
240};
241
242static const struct regulator_desc regulators[] = {
243	{
244		.name = "LDO1",
245		.id = LP3971_LDO1,
246		.ops = &lp3971_ldo_ops,
247		.n_voltages = ARRAY_SIZE(ldo123_voltage_map),
248		.volt_table = ldo123_voltage_map,
249		.type = REGULATOR_VOLTAGE,
250		.owner = THIS_MODULE,
251	},
252	{
253		.name = "LDO2",
254		.id = LP3971_LDO2,
255		.ops = &lp3971_ldo_ops,
256		.n_voltages = ARRAY_SIZE(ldo123_voltage_map),
257		.volt_table = ldo123_voltage_map,
258		.type = REGULATOR_VOLTAGE,
259		.owner = THIS_MODULE,
260	},
261	{
262		.name = "LDO3",
263		.id = LP3971_LDO3,
264		.ops = &lp3971_ldo_ops,
265		.n_voltages = ARRAY_SIZE(ldo123_voltage_map),
266		.volt_table = ldo123_voltage_map,
267		.type = REGULATOR_VOLTAGE,
268		.owner = THIS_MODULE,
269	},
270	{
271		.name = "LDO4",
272		.id = LP3971_LDO4,
273		.ops = &lp3971_ldo_ops,
274		.n_voltages = ARRAY_SIZE(ldo45_voltage_map),
275		.volt_table = ldo45_voltage_map,
276		.type = REGULATOR_VOLTAGE,
277		.owner = THIS_MODULE,
278	},
279	{
280		.name = "LDO5",
281		.id = LP3971_LDO5,
282		.ops = &lp3971_ldo_ops,
283		.n_voltages = ARRAY_SIZE(ldo45_voltage_map),
284		.volt_table = ldo45_voltage_map,
285		.type = REGULATOR_VOLTAGE,
286		.owner = THIS_MODULE,
287	},
288	{
289		.name = "DCDC1",
290		.id = LP3971_DCDC1,
291		.ops = &lp3971_dcdc_ops,
292		.n_voltages = ARRAY_SIZE(buck_voltage_map),
293		.volt_table = buck_voltage_map,
294		.type = REGULATOR_VOLTAGE,
295		.owner = THIS_MODULE,
296	},
297	{
298		.name = "DCDC2",
299		.id = LP3971_DCDC2,
300		.ops = &lp3971_dcdc_ops,
301		.n_voltages = ARRAY_SIZE(buck_voltage_map),
302		.volt_table = buck_voltage_map,
303		.type = REGULATOR_VOLTAGE,
304		.owner = THIS_MODULE,
305	},
306	{
307		.name = "DCDC3",
308		.id = LP3971_DCDC3,
309		.ops = &lp3971_dcdc_ops,
310		.n_voltages = ARRAY_SIZE(buck_voltage_map),
311		.volt_table = buck_voltage_map,
312		.type = REGULATOR_VOLTAGE,
313		.owner = THIS_MODULE,
314	},
315};
316
317static int lp3971_i2c_read(struct i2c_client *i2c, char reg, int count,
318	u16 *dest)
319{
320	int ret;
321
322	if (count != 1)
323		return -EIO;
324	ret = i2c_smbus_read_byte_data(i2c, reg);
325	if (ret < 0)
326		return ret;
327
328	*dest = ret;
329	return 0;
330}
331
332static int lp3971_i2c_write(struct i2c_client *i2c, char reg, int count,
333	const u16 *src)
334{
335	if (count != 1)
336		return -EIO;
337	return i2c_smbus_write_byte_data(i2c, reg, *src);
338}
339
340static u8 lp3971_reg_read(struct lp3971 *lp3971, u8 reg)
341{
342	u16 val = 0;
343
344	mutex_lock(&lp3971->io_lock);
345
346	lp3971_i2c_read(lp3971->i2c, reg, 1, &val);
347
348	dev_dbg(lp3971->dev, "reg read 0x%02x -> 0x%02x\n", (int)reg,
349		(unsigned)val&0xff);
350
351	mutex_unlock(&lp3971->io_lock);
352
353	return val & 0xff;
354}
355
356static int lp3971_set_bits(struct lp3971 *lp3971, u8 reg, u16 mask, u16 val)
357{
358	u16 tmp;
359	int ret;
360
361	mutex_lock(&lp3971->io_lock);
362
363	ret = lp3971_i2c_read(lp3971->i2c, reg, 1, &tmp);
364	if (ret == 0) {
365		tmp = (tmp & ~mask) | val;
366		ret = lp3971_i2c_write(lp3971->i2c, reg, 1, &tmp);
367		dev_dbg(lp3971->dev, "reg write 0x%02x -> 0x%02x\n", (int)reg,
368			(unsigned)val&0xff);
369	}
370	mutex_unlock(&lp3971->io_lock);
371
372	return ret;
373}
374
375static int setup_regulators(struct lp3971 *lp3971,
376				      struct lp3971_platform_data *pdata)
377{
378	int i, err;
379
380	/* Instantiate the regulators */
381	for (i = 0; i < pdata->num_regulators; i++) {
382		struct regulator_config config = { };
383		struct lp3971_regulator_subdev *reg = &pdata->regulators[i];
384		struct regulator_dev *rdev;
385
386		config.dev = lp3971->dev;
387		config.init_data = reg->initdata;
388		config.driver_data = lp3971;
389
390		rdev = devm_regulator_register(lp3971->dev,
391					       &regulators[reg->id], &config);
392		if (IS_ERR(rdev)) {
393			err = PTR_ERR(rdev);
394			dev_err(lp3971->dev, "regulator init failed: %d\n",
395				err);
396			return err;
397		}
398	}
399
400	return 0;
401}
402
403static int lp3971_i2c_probe(struct i2c_client *i2c)
404{
405	struct lp3971 *lp3971;
406	struct lp3971_platform_data *pdata = dev_get_platdata(&i2c->dev);
407	int ret;
408	u16 val;
409
410	if (!pdata) {
411		dev_dbg(&i2c->dev, "No platform init data supplied\n");
412		return -ENODEV;
413	}
414
415	lp3971 = devm_kzalloc(&i2c->dev, sizeof(struct lp3971), GFP_KERNEL);
416	if (lp3971 == NULL)
417		return -ENOMEM;
418
419	lp3971->i2c = i2c;
420	lp3971->dev = &i2c->dev;
421
422	mutex_init(&lp3971->io_lock);
423
424	/* Detect LP3971 */
425	ret = lp3971_i2c_read(i2c, LP3971_SYS_CONTROL1_REG, 1, &val);
426	if (ret == 0 && (val & SYS_CONTROL1_INIT_MASK) != SYS_CONTROL1_INIT_VAL)
427		ret = -ENODEV;
428	if (ret < 0) {
429		dev_err(&i2c->dev, "failed to detect device\n");
430		return ret;
431	}
432
433	ret = setup_regulators(lp3971, pdata);
434	if (ret < 0)
435		return ret;
436
437	i2c_set_clientdata(i2c, lp3971);
438	return 0;
439}
440
441static const struct i2c_device_id lp3971_i2c_id[] = {
442	{ "lp3971", 0 },
443	{ }
444};
445MODULE_DEVICE_TABLE(i2c, lp3971_i2c_id);
446
447static struct i2c_driver lp3971_i2c_driver = {
448	.driver = {
449		.name = "LP3971",
450		.probe_type = PROBE_PREFER_ASYNCHRONOUS,
451	},
452	.probe = lp3971_i2c_probe,
453	.id_table = lp3971_i2c_id,
454};
455
456module_i2c_driver(lp3971_i2c_driver);
457
458MODULE_LICENSE("GPL");
459MODULE_AUTHOR("Marek Szyprowski <m.szyprowski@samsung.com>");
460MODULE_DESCRIPTION("LP3971 PMIC driver");
461