1 /*
2  * Regulator driver for National Semiconductors LP3971 PMIC chip
3  *
4  *  Copyright (C) 2009 Samsung Electronics
5  *  Author: Marek Szyprowski <m.szyprowski@samsung.com>
6  *
7  * Based on wm8350.c
8  *
9  * This program is free software; you can redistribute it and/or modify
10  * it under the terms of the GNU General Public License version 2 as
11  * published by the Free Software Foundation.
12  *
13  */
14 
15 #include <linux/bug.h>
16 #include <linux/err.h>
17 #include <linux/i2c.h>
18 #include <linux/kernel.h>
19 #include <linux/module.h>
20 #include <linux/regulator/driver.h>
21 #include <linux/regulator/lp3971.h>
22 #include <linux/slab.h>
23 
24 struct lp3971 {
25 	struct device *dev;
26 	struct mutex io_lock;
27 	struct i2c_client *i2c;
28 };
29 
30 static u8 lp3971_reg_read(struct lp3971 *lp3971, u8 reg);
31 static int lp3971_set_bits(struct lp3971 *lp3971, u8 reg, u16 mask, u16 val);
32 
33 #define LP3971_SYS_CONTROL1_REG 0x07
34 
35 /* System control register 1 initial value,
36    bits 4 and 5 are EPROM programmable */
37 #define SYS_CONTROL1_INIT_VAL 0x40
38 #define SYS_CONTROL1_INIT_MASK 0xCF
39 
40 #define LP3971_BUCK_VOL_ENABLE_REG 0x10
41 #define LP3971_BUCK_VOL_CHANGE_REG 0x20
42 
43 /*	Voltage control registers shift:
44 	LP3971_BUCK1 -> 0
45 	LP3971_BUCK2 -> 4
46 	LP3971_BUCK3 -> 6
47 */
48 #define BUCK_VOL_CHANGE_SHIFT(x) (((!!x) << 2) | (x & ~0x01))
49 #define BUCK_VOL_CHANGE_FLAG_GO 0x01
50 #define BUCK_VOL_CHANGE_FLAG_TARGET 0x02
51 #define BUCK_VOL_CHANGE_FLAG_MASK 0x03
52 
53 #define LP3971_BUCK1_BASE 0x23
54 #define LP3971_BUCK2_BASE 0x29
55 #define LP3971_BUCK3_BASE 0x32
56 
57 static const int buck_base_addr[] = {
58 	LP3971_BUCK1_BASE,
59 	LP3971_BUCK2_BASE,
60 	LP3971_BUCK3_BASE,
61 };
62 
63 #define LP3971_BUCK_TARGET_VOL1_REG(x) (buck_base_addr[x])
64 #define LP3971_BUCK_TARGET_VOL2_REG(x) (buck_base_addr[x]+1)
65 
66 static const unsigned int buck_voltage_map[] = {
67 	      0,  800000,  850000,  900000,  950000, 1000000, 1050000, 1100000,
68 	1150000, 1200000, 1250000, 1300000, 1350000, 1400000, 1450000, 1500000,
69 	1550000, 1600000, 1650000, 1700000, 1800000, 1900000, 2500000, 2800000,
70 	3000000, 3300000,
71 };
72 
73 #define BUCK_TARGET_VOL_MASK 0x3f
74 
75 #define LP3971_BUCK_RAMP_REG(x)	(buck_base_addr[x]+2)
76 
77 #define LP3971_LDO_ENABLE_REG 0x12
78 #define LP3971_LDO_VOL_CONTR_BASE 0x39
79 
80 /*	Voltage control registers:
81 	LP3971_LDO1 -> LP3971_LDO_VOL_CONTR_BASE + 0
82 	LP3971_LDO2 -> LP3971_LDO_VOL_CONTR_BASE + 0
83 	LP3971_LDO3 -> LP3971_LDO_VOL_CONTR_BASE + 1
84 	LP3971_LDO4 -> LP3971_LDO_VOL_CONTR_BASE + 1
85 	LP3971_LDO5 -> LP3971_LDO_VOL_CONTR_BASE + 2
86 */
87 #define LP3971_LDO_VOL_CONTR_REG(x)	(LP3971_LDO_VOL_CONTR_BASE + (x >> 1))
88 
89 /*	Voltage control registers shift:
90 	LP3971_LDO1 -> 0, LP3971_LDO2 -> 4
91 	LP3971_LDO3 -> 0, LP3971_LDO4 -> 4
92 	LP3971_LDO5 -> 0
93 */
94 #define LDO_VOL_CONTR_SHIFT(x) ((x & 1) << 2)
95 #define LDO_VOL_CONTR_MASK 0x0f
96 
97 static const unsigned int ldo45_voltage_map[] = {
98 	1000000, 1050000, 1100000, 1150000, 1200000, 1250000, 1300000, 1350000,
99 	1400000, 1500000, 1800000, 1900000, 2500000, 2800000, 3000000, 3300000,
100 };
101 
102 static const unsigned int ldo123_voltage_map[] = {
103 	1800000, 1900000, 2000000, 2100000, 2200000, 2300000, 2400000, 2500000,
104 	2600000, 2700000, 2800000, 2900000, 3000000, 3100000, 3200000, 3300000,
105 };
106 
107 #define LDO_VOL_MIN_IDX 0x00
108 #define LDO_VOL_MAX_IDX 0x0f
109 
lp3971_ldo_is_enabled(struct regulator_dev * dev)110 static int lp3971_ldo_is_enabled(struct regulator_dev *dev)
111 {
112 	struct lp3971 *lp3971 = rdev_get_drvdata(dev);
113 	int ldo = rdev_get_id(dev) - LP3971_LDO1;
114 	u16 mask = 1 << (1 + ldo);
115 	u16 val;
116 
117 	val = lp3971_reg_read(lp3971, LP3971_LDO_ENABLE_REG);
118 	return (val & mask) != 0;
119 }
120 
lp3971_ldo_enable(struct regulator_dev * dev)121 static int lp3971_ldo_enable(struct regulator_dev *dev)
122 {
123 	struct lp3971 *lp3971 = rdev_get_drvdata(dev);
124 	int ldo = rdev_get_id(dev) - LP3971_LDO1;
125 	u16 mask = 1 << (1 + ldo);
126 
127 	return lp3971_set_bits(lp3971, LP3971_LDO_ENABLE_REG, mask, mask);
128 }
129 
lp3971_ldo_disable(struct regulator_dev * dev)130 static int lp3971_ldo_disable(struct regulator_dev *dev)
131 {
132 	struct lp3971 *lp3971 = rdev_get_drvdata(dev);
133 	int ldo = rdev_get_id(dev) - LP3971_LDO1;
134 	u16 mask = 1 << (1 + ldo);
135 
136 	return lp3971_set_bits(lp3971, LP3971_LDO_ENABLE_REG, mask, 0);
137 }
138 
lp3971_ldo_get_voltage_sel(struct regulator_dev * dev)139 static int lp3971_ldo_get_voltage_sel(struct regulator_dev *dev)
140 {
141 	struct lp3971 *lp3971 = rdev_get_drvdata(dev);
142 	int ldo = rdev_get_id(dev) - LP3971_LDO1;
143 	u16 val, reg;
144 
145 	reg = lp3971_reg_read(lp3971, LP3971_LDO_VOL_CONTR_REG(ldo));
146 	val = (reg >> LDO_VOL_CONTR_SHIFT(ldo)) & LDO_VOL_CONTR_MASK;
147 
148 	return val;
149 }
150 
lp3971_ldo_set_voltage_sel(struct regulator_dev * dev,unsigned int selector)151 static int lp3971_ldo_set_voltage_sel(struct regulator_dev *dev,
152 				      unsigned int selector)
153 {
154 	struct lp3971 *lp3971 = rdev_get_drvdata(dev);
155 	int ldo = rdev_get_id(dev) - LP3971_LDO1;
156 
157 	return lp3971_set_bits(lp3971, LP3971_LDO_VOL_CONTR_REG(ldo),
158 			LDO_VOL_CONTR_MASK << LDO_VOL_CONTR_SHIFT(ldo),
159 			selector << LDO_VOL_CONTR_SHIFT(ldo));
160 }
161 
162 static struct regulator_ops lp3971_ldo_ops = {
163 	.list_voltage = regulator_list_voltage_table,
164 	.map_voltage = regulator_map_voltage_ascend,
165 	.is_enabled = lp3971_ldo_is_enabled,
166 	.enable = lp3971_ldo_enable,
167 	.disable = lp3971_ldo_disable,
168 	.get_voltage_sel = lp3971_ldo_get_voltage_sel,
169 	.set_voltage_sel = lp3971_ldo_set_voltage_sel,
170 };
171 
lp3971_dcdc_is_enabled(struct regulator_dev * dev)172 static int lp3971_dcdc_is_enabled(struct regulator_dev *dev)
173 {
174 	struct lp3971 *lp3971 = rdev_get_drvdata(dev);
175 	int buck = rdev_get_id(dev) - LP3971_DCDC1;
176 	u16 mask = 1 << (buck * 2);
177 	u16 val;
178 
179 	val = lp3971_reg_read(lp3971, LP3971_BUCK_VOL_ENABLE_REG);
180 	return (val & mask) != 0;
181 }
182 
lp3971_dcdc_enable(struct regulator_dev * dev)183 static int lp3971_dcdc_enable(struct regulator_dev *dev)
184 {
185 	struct lp3971 *lp3971 = rdev_get_drvdata(dev);
186 	int buck = rdev_get_id(dev) - LP3971_DCDC1;
187 	u16 mask = 1 << (buck * 2);
188 
189 	return lp3971_set_bits(lp3971, LP3971_BUCK_VOL_ENABLE_REG, mask, mask);
190 }
191 
lp3971_dcdc_disable(struct regulator_dev * dev)192 static int lp3971_dcdc_disable(struct regulator_dev *dev)
193 {
194 	struct lp3971 *lp3971 = rdev_get_drvdata(dev);
195 	int buck = rdev_get_id(dev) - LP3971_DCDC1;
196 	u16 mask = 1 << (buck * 2);
197 
198 	return lp3971_set_bits(lp3971, LP3971_BUCK_VOL_ENABLE_REG, mask, 0);
199 }
200 
lp3971_dcdc_get_voltage_sel(struct regulator_dev * dev)201 static int lp3971_dcdc_get_voltage_sel(struct regulator_dev *dev)
202 {
203 	struct lp3971 *lp3971 = rdev_get_drvdata(dev);
204 	int buck = rdev_get_id(dev) - LP3971_DCDC1;
205 	u16 reg;
206 
207 	reg = lp3971_reg_read(lp3971, LP3971_BUCK_TARGET_VOL1_REG(buck));
208 	reg &= BUCK_TARGET_VOL_MASK;
209 
210 	return reg;
211 }
212 
lp3971_dcdc_set_voltage_sel(struct regulator_dev * dev,unsigned int selector)213 static int lp3971_dcdc_set_voltage_sel(struct regulator_dev *dev,
214 				       unsigned int selector)
215 {
216 	struct lp3971 *lp3971 = rdev_get_drvdata(dev);
217 	int buck = rdev_get_id(dev) - LP3971_DCDC1;
218 	int ret;
219 
220 	ret = lp3971_set_bits(lp3971, LP3971_BUCK_TARGET_VOL1_REG(buck),
221 	       BUCK_TARGET_VOL_MASK, selector);
222 	if (ret)
223 		return ret;
224 
225 	ret = lp3971_set_bits(lp3971, LP3971_BUCK_VOL_CHANGE_REG,
226 	       BUCK_VOL_CHANGE_FLAG_MASK << BUCK_VOL_CHANGE_SHIFT(buck),
227 	       BUCK_VOL_CHANGE_FLAG_GO << BUCK_VOL_CHANGE_SHIFT(buck));
228 	if (ret)
229 		return ret;
230 
231 	return lp3971_set_bits(lp3971, LP3971_BUCK_VOL_CHANGE_REG,
232 	       BUCK_VOL_CHANGE_FLAG_MASK << BUCK_VOL_CHANGE_SHIFT(buck),
233 	       0 << BUCK_VOL_CHANGE_SHIFT(buck));
234 }
235 
236 static struct regulator_ops lp3971_dcdc_ops = {
237 	.list_voltage = regulator_list_voltage_table,
238 	.map_voltage = regulator_map_voltage_ascend,
239 	.is_enabled = lp3971_dcdc_is_enabled,
240 	.enable = lp3971_dcdc_enable,
241 	.disable = lp3971_dcdc_disable,
242 	.get_voltage_sel = lp3971_dcdc_get_voltage_sel,
243 	.set_voltage_sel = lp3971_dcdc_set_voltage_sel,
244 };
245 
246 static const struct regulator_desc regulators[] = {
247 	{
248 		.name = "LDO1",
249 		.id = LP3971_LDO1,
250 		.ops = &lp3971_ldo_ops,
251 		.n_voltages = ARRAY_SIZE(ldo123_voltage_map),
252 		.volt_table = ldo123_voltage_map,
253 		.type = REGULATOR_VOLTAGE,
254 		.owner = THIS_MODULE,
255 	},
256 	{
257 		.name = "LDO2",
258 		.id = LP3971_LDO2,
259 		.ops = &lp3971_ldo_ops,
260 		.n_voltages = ARRAY_SIZE(ldo123_voltage_map),
261 		.volt_table = ldo123_voltage_map,
262 		.type = REGULATOR_VOLTAGE,
263 		.owner = THIS_MODULE,
264 	},
265 	{
266 		.name = "LDO3",
267 		.id = LP3971_LDO3,
268 		.ops = &lp3971_ldo_ops,
269 		.n_voltages = ARRAY_SIZE(ldo123_voltage_map),
270 		.volt_table = ldo123_voltage_map,
271 		.type = REGULATOR_VOLTAGE,
272 		.owner = THIS_MODULE,
273 	},
274 	{
275 		.name = "LDO4",
276 		.id = LP3971_LDO4,
277 		.ops = &lp3971_ldo_ops,
278 		.n_voltages = ARRAY_SIZE(ldo45_voltage_map),
279 		.volt_table = ldo45_voltage_map,
280 		.type = REGULATOR_VOLTAGE,
281 		.owner = THIS_MODULE,
282 	},
283 	{
284 		.name = "LDO5",
285 		.id = LP3971_LDO5,
286 		.ops = &lp3971_ldo_ops,
287 		.n_voltages = ARRAY_SIZE(ldo45_voltage_map),
288 		.volt_table = ldo45_voltage_map,
289 		.type = REGULATOR_VOLTAGE,
290 		.owner = THIS_MODULE,
291 	},
292 	{
293 		.name = "DCDC1",
294 		.id = LP3971_DCDC1,
295 		.ops = &lp3971_dcdc_ops,
296 		.n_voltages = ARRAY_SIZE(buck_voltage_map),
297 		.volt_table = buck_voltage_map,
298 		.type = REGULATOR_VOLTAGE,
299 		.owner = THIS_MODULE,
300 	},
301 	{
302 		.name = "DCDC2",
303 		.id = LP3971_DCDC2,
304 		.ops = &lp3971_dcdc_ops,
305 		.n_voltages = ARRAY_SIZE(buck_voltage_map),
306 		.volt_table = buck_voltage_map,
307 		.type = REGULATOR_VOLTAGE,
308 		.owner = THIS_MODULE,
309 	},
310 	{
311 		.name = "DCDC3",
312 		.id = LP3971_DCDC3,
313 		.ops = &lp3971_dcdc_ops,
314 		.n_voltages = ARRAY_SIZE(buck_voltage_map),
315 		.volt_table = buck_voltage_map,
316 		.type = REGULATOR_VOLTAGE,
317 		.owner = THIS_MODULE,
318 	},
319 };
320 
lp3971_i2c_read(struct i2c_client * i2c,char reg,int count,u16 * dest)321 static int lp3971_i2c_read(struct i2c_client *i2c, char reg, int count,
322 	u16 *dest)
323 {
324 	int ret;
325 
326 	if (count != 1)
327 		return -EIO;
328 	ret = i2c_smbus_read_byte_data(i2c, reg);
329 	if (ret < 0)
330 		return ret;
331 
332 	*dest = ret;
333 	return 0;
334 }
335 
lp3971_i2c_write(struct i2c_client * i2c,char reg,int count,const u16 * src)336 static int lp3971_i2c_write(struct i2c_client *i2c, char reg, int count,
337 	const u16 *src)
338 {
339 	if (count != 1)
340 		return -EIO;
341 	return i2c_smbus_write_byte_data(i2c, reg, *src);
342 }
343 
lp3971_reg_read(struct lp3971 * lp3971,u8 reg)344 static u8 lp3971_reg_read(struct lp3971 *lp3971, u8 reg)
345 {
346 	u16 val = 0;
347 
348 	mutex_lock(&lp3971->io_lock);
349 
350 	lp3971_i2c_read(lp3971->i2c, reg, 1, &val);
351 
352 	dev_dbg(lp3971->dev, "reg read 0x%02x -> 0x%02x\n", (int)reg,
353 		(unsigned)val&0xff);
354 
355 	mutex_unlock(&lp3971->io_lock);
356 
357 	return val & 0xff;
358 }
359 
lp3971_set_bits(struct lp3971 * lp3971,u8 reg,u16 mask,u16 val)360 static int lp3971_set_bits(struct lp3971 *lp3971, u8 reg, u16 mask, u16 val)
361 {
362 	u16 tmp;
363 	int ret;
364 
365 	mutex_lock(&lp3971->io_lock);
366 
367 	ret = lp3971_i2c_read(lp3971->i2c, reg, 1, &tmp);
368 	if (ret == 0) {
369 		tmp = (tmp & ~mask) | val;
370 		ret = lp3971_i2c_write(lp3971->i2c, reg, 1, &tmp);
371 		dev_dbg(lp3971->dev, "reg write 0x%02x -> 0x%02x\n", (int)reg,
372 			(unsigned)val&0xff);
373 	}
374 	mutex_unlock(&lp3971->io_lock);
375 
376 	return ret;
377 }
378 
setup_regulators(struct lp3971 * lp3971,struct lp3971_platform_data * pdata)379 static int setup_regulators(struct lp3971 *lp3971,
380 				      struct lp3971_platform_data *pdata)
381 {
382 	int i, err;
383 
384 	/* Instantiate the regulators */
385 	for (i = 0; i < pdata->num_regulators; i++) {
386 		struct regulator_config config = { };
387 		struct lp3971_regulator_subdev *reg = &pdata->regulators[i];
388 		struct regulator_dev *rdev;
389 
390 		config.dev = lp3971->dev;
391 		config.init_data = reg->initdata;
392 		config.driver_data = lp3971;
393 
394 		rdev = devm_regulator_register(lp3971->dev,
395 					       &regulators[reg->id], &config);
396 		if (IS_ERR(rdev)) {
397 			err = PTR_ERR(rdev);
398 			dev_err(lp3971->dev, "regulator init failed: %d\n",
399 				err);
400 			return err;
401 		}
402 	}
403 
404 	return 0;
405 }
406 
lp3971_i2c_probe(struct i2c_client * i2c,const struct i2c_device_id * id)407 static int lp3971_i2c_probe(struct i2c_client *i2c,
408 			    const struct i2c_device_id *id)
409 {
410 	struct lp3971 *lp3971;
411 	struct lp3971_platform_data *pdata = dev_get_platdata(&i2c->dev);
412 	int ret;
413 	u16 val;
414 
415 	if (!pdata) {
416 		dev_dbg(&i2c->dev, "No platform init data supplied\n");
417 		return -ENODEV;
418 	}
419 
420 	lp3971 = devm_kzalloc(&i2c->dev, sizeof(struct lp3971), GFP_KERNEL);
421 	if (lp3971 == NULL)
422 		return -ENOMEM;
423 
424 	lp3971->i2c = i2c;
425 	lp3971->dev = &i2c->dev;
426 
427 	mutex_init(&lp3971->io_lock);
428 
429 	/* Detect LP3971 */
430 	ret = lp3971_i2c_read(i2c, LP3971_SYS_CONTROL1_REG, 1, &val);
431 	if (ret == 0 && (val & SYS_CONTROL1_INIT_MASK) != SYS_CONTROL1_INIT_VAL)
432 		ret = -ENODEV;
433 	if (ret < 0) {
434 		dev_err(&i2c->dev, "failed to detect device\n");
435 		return ret;
436 	}
437 
438 	ret = setup_regulators(lp3971, pdata);
439 	if (ret < 0)
440 		return ret;
441 
442 	i2c_set_clientdata(i2c, lp3971);
443 	return 0;
444 }
445 
446 static const struct i2c_device_id lp3971_i2c_id[] = {
447 	{ "lp3971", 0 },
448 	{ }
449 };
450 MODULE_DEVICE_TABLE(i2c, lp3971_i2c_id);
451 
452 static struct i2c_driver lp3971_i2c_driver = {
453 	.driver = {
454 		.name = "LP3971",
455 	},
456 	.probe    = lp3971_i2c_probe,
457 	.id_table = lp3971_i2c_id,
458 };
459 
460 module_i2c_driver(lp3971_i2c_driver);
461 
462 MODULE_LICENSE("GPL");
463 MODULE_AUTHOR("Marek Szyprowski <m.szyprowski@samsung.com>");
464 MODULE_DESCRIPTION("LP3971 PMIC driver");
465