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 
20 struct lp3971 {
21 	struct device *dev;
22 	struct mutex io_lock;
23 	struct i2c_client *i2c;
24 };
25 
26 static u8 lp3971_reg_read(struct lp3971 *lp3971, u8 reg);
27 static 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 
53 static 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 
62 static 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 
93 static 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 
98 static 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 
lp3971_ldo_is_enabled(struct regulator_dev * dev)106 static 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 
lp3971_ldo_enable(struct regulator_dev * dev)117 static 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 
lp3971_ldo_disable(struct regulator_dev * dev)126 static 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 
lp3971_ldo_get_voltage_sel(struct regulator_dev * dev)135 static 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 
lp3971_ldo_set_voltage_sel(struct regulator_dev * dev,unsigned int selector)147 static 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 
158 static 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 
lp3971_dcdc_is_enabled(struct regulator_dev * dev)168 static 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 
lp3971_dcdc_enable(struct regulator_dev * dev)179 static 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 
lp3971_dcdc_disable(struct regulator_dev * dev)188 static 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 
lp3971_dcdc_get_voltage_sel(struct regulator_dev * dev)197 static 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 
lp3971_dcdc_set_voltage_sel(struct regulator_dev * dev,unsigned int selector)209 static 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 
232 static 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 
242 static 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 
lp3971_i2c_read(struct i2c_client * i2c,char reg,int count,u16 * dest)317 static 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 
lp3971_i2c_write(struct i2c_client * i2c,char reg,int count,const u16 * src)332 static 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 
lp3971_reg_read(struct lp3971 * lp3971,u8 reg)340 static 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 
lp3971_set_bits(struct lp3971 * lp3971,u8 reg,u16 mask,u16 val)356 static 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 
setup_regulators(struct lp3971 * lp3971,struct lp3971_platform_data * pdata)375 static 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 
lp3971_i2c_probe(struct i2c_client * i2c)403 static 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 
441 static const struct i2c_device_id lp3971_i2c_id[] = {
442 	{ "lp3971", 0 },
443 	{ }
444 };
445 MODULE_DEVICE_TABLE(i2c, lp3971_i2c_id);
446 
447 static struct i2c_driver lp3971_i2c_driver = {
448 	.driver = {
449 		.name = "LP3971",
450 	},
451 	.probe_new = lp3971_i2c_probe,
452 	.id_table = lp3971_i2c_id,
453 };
454 
455 module_i2c_driver(lp3971_i2c_driver);
456 
457 MODULE_LICENSE("GPL");
458 MODULE_AUTHOR("Marek Szyprowski <m.szyprowski@samsung.com>");
459 MODULE_DESCRIPTION("LP3971 PMIC driver");
460