xref: /linux/drivers/regulator/lp3971.c (revision d39d0ed196aa1685bb24771e92f78633c66ac9cb)
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/regulator/driver.h>
20 #include <linux/regulator/lp3971.h>
21 #include <linux/slab.h>
22 
23 struct lp3971 {
24 	struct device *dev;
25 	struct mutex io_lock;
26 	struct i2c_client *i2c;
27 	int num_regulators;
28 	struct regulator_dev **rdev;
29 };
30 
31 static u8 lp3971_reg_read(struct lp3971 *lp3971, u8 reg);
32 static int lp3971_set_bits(struct lp3971 *lp3971, u8 reg, u16 mask, u16 val);
33 
34 #define LP3971_SYS_CONTROL1_REG 0x07
35 
36 /* System control register 1 initial value,
37    bits 4 and 5 are EPROM programmable */
38 #define SYS_CONTROL1_INIT_VAL 0x40
39 #define SYS_CONTROL1_INIT_MASK 0xCF
40 
41 #define LP3971_BUCK_VOL_ENABLE_REG 0x10
42 #define LP3971_BUCK_VOL_CHANGE_REG 0x20
43 
44 /*	Voltage control registers shift:
45 	LP3971_BUCK1 -> 0
46 	LP3971_BUCK2 -> 4
47 	LP3971_BUCK3 -> 6
48 */
49 #define BUCK_VOL_CHANGE_SHIFT(x) (((!!x) << 2) | (x & ~0x01))
50 #define BUCK_VOL_CHANGE_FLAG_GO 0x01
51 #define BUCK_VOL_CHANGE_FLAG_TARGET 0x02
52 #define BUCK_VOL_CHANGE_FLAG_MASK 0x03
53 
54 #define LP3971_BUCK1_BASE 0x23
55 #define LP3971_BUCK2_BASE 0x29
56 #define LP3971_BUCK3_BASE 0x32
57 
58 static const int buck_base_addr[] = {
59 	LP3971_BUCK1_BASE,
60 	LP3971_BUCK2_BASE,
61 	LP3971_BUCK3_BASE,
62 };
63 
64 #define LP3971_BUCK_TARGET_VOL1_REG(x) (buck_base_addr[x])
65 #define LP3971_BUCK_TARGET_VOL2_REG(x) (buck_base_addr[x]+1)
66 
67 static const int buck_voltage_map[] = {
68 	   0,  800,  850,  900,  950, 1000, 1050, 1100,
69 	1150, 1200, 1250, 1300, 1350, 1400, 1450, 1500,
70 	1550, 1600, 1650, 1700, 1800, 1900, 2500, 2800,
71 	3000, 3300,
72 };
73 
74 #define BUCK_TARGET_VOL_MASK 0x3f
75 #define BUCK_TARGET_VOL_MIN_IDX 0x01
76 #define BUCK_TARGET_VOL_MAX_IDX 0x19
77 
78 #define LP3971_BUCK_RAMP_REG(x)	(buck_base_addr[x]+2)
79 
80 #define LP3971_LDO_ENABLE_REG 0x12
81 #define LP3971_LDO_VOL_CONTR_BASE 0x39
82 
83 /*	Voltage control registers:
84 	LP3971_LDO1 -> LP3971_LDO_VOL_CONTR_BASE + 0
85 	LP3971_LDO2 -> LP3971_LDO_VOL_CONTR_BASE + 0
86 	LP3971_LDO3 -> LP3971_LDO_VOL_CONTR_BASE + 1
87 	LP3971_LDO4 -> LP3971_LDO_VOL_CONTR_BASE + 1
88 	LP3971_LDO5 -> LP3971_LDO_VOL_CONTR_BASE + 2
89 */
90 #define LP3971_LDO_VOL_CONTR_REG(x)	(LP3971_LDO_VOL_CONTR_BASE + (x >> 1))
91 
92 /*	Voltage control registers shift:
93 	LP3971_LDO1 -> 0, LP3971_LDO2 -> 4
94 	LP3971_LDO3 -> 0, LP3971_LDO4 -> 4
95 	LP3971_LDO5 -> 0
96 */
97 #define LDO_VOL_CONTR_SHIFT(x) ((x & 1) << 2)
98 #define LDO_VOL_CONTR_MASK 0x0f
99 
100 static const int ldo45_voltage_map[] = {
101 	1000, 1050, 1100, 1150, 1200, 1250, 1300, 1350,
102 	1400, 1500, 1800, 1900, 2500, 2800, 3000, 3300,
103 };
104 
105 static const int ldo123_voltage_map[] = {
106 	1800, 1900, 2000, 2100, 2200, 2300, 2400, 2500,
107 	2600, 2700, 2800, 2900, 3000, 3100, 3200, 3300,
108 };
109 
110 static const int *ldo_voltage_map[] = {
111 	ldo123_voltage_map, /* LDO1 */
112 	ldo123_voltage_map, /* LDO2 */
113 	ldo123_voltage_map, /* LDO3 */
114 	ldo45_voltage_map, /* LDO4 */
115 	ldo45_voltage_map, /* LDO5 */
116 };
117 
118 #define LDO_VOL_VALUE_MAP(x) (ldo_voltage_map[(x - LP3971_LDO1)])
119 
120 #define LDO_VOL_MIN_IDX 0x00
121 #define LDO_VOL_MAX_IDX 0x0f
122 
123 static int lp3971_ldo_list_voltage(struct regulator_dev *dev, unsigned index)
124 {
125 	int ldo = rdev_get_id(dev) - LP3971_LDO1;
126 	return 1000 * LDO_VOL_VALUE_MAP(ldo)[index];
127 }
128 
129 static int lp3971_ldo_is_enabled(struct regulator_dev *dev)
130 {
131 	struct lp3971 *lp3971 = rdev_get_drvdata(dev);
132 	int ldo = rdev_get_id(dev) - LP3971_LDO1;
133 	u16 mask = 1 << (1 + ldo);
134 	u16 val;
135 
136 	val = lp3971_reg_read(lp3971, LP3971_LDO_ENABLE_REG);
137 	return (val & mask) != 0;
138 }
139 
140 static int lp3971_ldo_enable(struct regulator_dev *dev)
141 {
142 	struct lp3971 *lp3971 = rdev_get_drvdata(dev);
143 	int ldo = rdev_get_id(dev) - LP3971_LDO1;
144 	u16 mask = 1 << (1 + ldo);
145 
146 	return lp3971_set_bits(lp3971, LP3971_LDO_ENABLE_REG, mask, mask);
147 }
148 
149 static int lp3971_ldo_disable(struct regulator_dev *dev)
150 {
151 	struct lp3971 *lp3971 = rdev_get_drvdata(dev);
152 	int ldo = rdev_get_id(dev) - LP3971_LDO1;
153 	u16 mask = 1 << (1 + ldo);
154 
155 	return lp3971_set_bits(lp3971, LP3971_LDO_ENABLE_REG, mask, 0);
156 }
157 
158 static int lp3971_ldo_get_voltage(struct regulator_dev *dev)
159 {
160 	struct lp3971 *lp3971 = rdev_get_drvdata(dev);
161 	int ldo = rdev_get_id(dev) - LP3971_LDO1;
162 	u16 val, reg;
163 
164 	reg = lp3971_reg_read(lp3971, LP3971_LDO_VOL_CONTR_REG(ldo));
165 	val = (reg >> LDO_VOL_CONTR_SHIFT(ldo)) & LDO_VOL_CONTR_MASK;
166 
167 	return 1000 * LDO_VOL_VALUE_MAP(ldo)[val];
168 }
169 
170 static int lp3971_ldo_set_voltage(struct regulator_dev *dev,
171 				  int min_uV, int max_uV)
172 {
173 	struct lp3971 *lp3971 = rdev_get_drvdata(dev);
174 	int ldo = rdev_get_id(dev) - LP3971_LDO1;
175 	int min_vol = min_uV / 1000, max_vol = max_uV / 1000;
176 	const int *vol_map = LDO_VOL_VALUE_MAP(ldo);
177 	u16 val;
178 
179 	if (min_vol < vol_map[LDO_VOL_MIN_IDX] ||
180 	    min_vol > vol_map[LDO_VOL_MAX_IDX])
181 		return -EINVAL;
182 
183 	for (val = LDO_VOL_MIN_IDX; val <= LDO_VOL_MAX_IDX; val++)
184 		if (vol_map[val] >= min_vol)
185 			break;
186 
187 	if (val > LDO_VOL_MAX_IDX || vol_map[val] > max_vol)
188 		return -EINVAL;
189 
190 	return lp3971_set_bits(lp3971, LP3971_LDO_VOL_CONTR_REG(ldo),
191 			LDO_VOL_CONTR_MASK << LDO_VOL_CONTR_SHIFT(ldo),
192 			val << LDO_VOL_CONTR_SHIFT(ldo));
193 }
194 
195 static struct regulator_ops lp3971_ldo_ops = {
196 	.list_voltage = lp3971_ldo_list_voltage,
197 	.is_enabled = lp3971_ldo_is_enabled,
198 	.enable = lp3971_ldo_enable,
199 	.disable = lp3971_ldo_disable,
200 	.get_voltage = lp3971_ldo_get_voltage,
201 	.set_voltage = lp3971_ldo_set_voltage,
202 };
203 
204 static int lp3971_dcdc_list_voltage(struct regulator_dev *dev, unsigned index)
205 {
206 	return 1000 * buck_voltage_map[index];
207 }
208 
209 static int lp3971_dcdc_is_enabled(struct regulator_dev *dev)
210 {
211 	struct lp3971 *lp3971 = rdev_get_drvdata(dev);
212 	int buck = rdev_get_id(dev) - LP3971_DCDC1;
213 	u16 mask = 1 << (buck * 2);
214 	u16 val;
215 
216 	val = lp3971_reg_read(lp3971, LP3971_BUCK_VOL_ENABLE_REG);
217 	return (val & mask) != 0;
218 }
219 
220 static int lp3971_dcdc_enable(struct regulator_dev *dev)
221 {
222 	struct lp3971 *lp3971 = rdev_get_drvdata(dev);
223 	int buck = rdev_get_id(dev) - LP3971_DCDC1;
224 	u16 mask = 1 << (buck * 2);
225 
226 	return lp3971_set_bits(lp3971, LP3971_BUCK_VOL_ENABLE_REG, mask, mask);
227 }
228 
229 static int lp3971_dcdc_disable(struct regulator_dev *dev)
230 {
231 	struct lp3971 *lp3971 = rdev_get_drvdata(dev);
232 	int buck = rdev_get_id(dev) - LP3971_DCDC1;
233 	u16 mask = 1 << (buck * 2);
234 
235 	return lp3971_set_bits(lp3971, LP3971_BUCK_VOL_ENABLE_REG, mask, 0);
236 }
237 
238 static int lp3971_dcdc_get_voltage(struct regulator_dev *dev)
239 {
240 	struct lp3971 *lp3971 = rdev_get_drvdata(dev);
241 	int buck = rdev_get_id(dev) - LP3971_DCDC1;
242 	u16 reg;
243 	int val;
244 
245 	reg = lp3971_reg_read(lp3971, LP3971_BUCK_TARGET_VOL1_REG(buck));
246 	reg &= BUCK_TARGET_VOL_MASK;
247 
248 	if (reg <= BUCK_TARGET_VOL_MAX_IDX)
249 		val = 1000 * buck_voltage_map[reg];
250 	else {
251 		val = 0;
252 		dev_warn(&dev->dev, "chip reported incorrect voltage value.\n");
253 	}
254 
255 	return val;
256 }
257 
258 static int lp3971_dcdc_set_voltage(struct regulator_dev *dev,
259 				  int min_uV, int max_uV)
260 {
261 	struct lp3971 *lp3971 = rdev_get_drvdata(dev);
262 	int buck = rdev_get_id(dev) - LP3971_DCDC1;
263 	int min_vol = min_uV / 1000, max_vol = max_uV / 1000;
264 	const int *vol_map = buck_voltage_map;
265 	u16 val;
266 	int ret;
267 
268 	if (min_vol < vol_map[BUCK_TARGET_VOL_MIN_IDX] ||
269 	    min_vol > vol_map[BUCK_TARGET_VOL_MAX_IDX])
270 		return -EINVAL;
271 
272 	for (val = BUCK_TARGET_VOL_MIN_IDX; val <= BUCK_TARGET_VOL_MAX_IDX;
273 	     val++)
274 		if (vol_map[val] >= min_vol)
275 			break;
276 
277 	if (val > BUCK_TARGET_VOL_MAX_IDX || vol_map[val] > max_vol)
278 		return -EINVAL;
279 
280 	ret = lp3971_set_bits(lp3971, LP3971_BUCK_TARGET_VOL1_REG(buck),
281 	       BUCK_TARGET_VOL_MASK, val);
282 	if (ret)
283 		return ret;
284 
285 	ret = lp3971_set_bits(lp3971, LP3971_BUCK_VOL_CHANGE_REG,
286 	       BUCK_VOL_CHANGE_FLAG_MASK << BUCK_VOL_CHANGE_SHIFT(buck),
287 	       BUCK_VOL_CHANGE_FLAG_GO << BUCK_VOL_CHANGE_SHIFT(buck));
288 	if (ret)
289 		return ret;
290 
291 	return lp3971_set_bits(lp3971, LP3971_BUCK_VOL_CHANGE_REG,
292 	       BUCK_VOL_CHANGE_FLAG_MASK << BUCK_VOL_CHANGE_SHIFT(buck),
293 	       0 << BUCK_VOL_CHANGE_SHIFT(buck));
294 }
295 
296 static struct regulator_ops lp3971_dcdc_ops = {
297 	.list_voltage = lp3971_dcdc_list_voltage,
298 	.is_enabled = lp3971_dcdc_is_enabled,
299 	.enable = lp3971_dcdc_enable,
300 	.disable = lp3971_dcdc_disable,
301 	.get_voltage = lp3971_dcdc_get_voltage,
302 	.set_voltage = lp3971_dcdc_set_voltage,
303 };
304 
305 static struct regulator_desc regulators[] = {
306 	{
307 		.name = "LDO1",
308 		.id = LP3971_LDO1,
309 		.ops = &lp3971_ldo_ops,
310 		.n_voltages = ARRAY_SIZE(ldo123_voltage_map),
311 		.type = REGULATOR_VOLTAGE,
312 		.owner = THIS_MODULE,
313 	},
314 	{
315 		.name = "LDO2",
316 		.id = LP3971_LDO2,
317 		.ops = &lp3971_ldo_ops,
318 		.n_voltages = ARRAY_SIZE(ldo123_voltage_map),
319 		.type = REGULATOR_VOLTAGE,
320 		.owner = THIS_MODULE,
321 	},
322 	{
323 		.name = "LDO3",
324 		.id = LP3971_LDO3,
325 		.ops = &lp3971_ldo_ops,
326 		.n_voltages = ARRAY_SIZE(ldo123_voltage_map),
327 		.type = REGULATOR_VOLTAGE,
328 		.owner = THIS_MODULE,
329 	},
330 	{
331 		.name = "LDO4",
332 		.id = LP3971_LDO4,
333 		.ops = &lp3971_ldo_ops,
334 		.n_voltages = ARRAY_SIZE(ldo45_voltage_map),
335 		.type = REGULATOR_VOLTAGE,
336 		.owner = THIS_MODULE,
337 	},
338 	{
339 		.name = "LDO5",
340 		.id = LP3971_LDO5,
341 		.ops = &lp3971_ldo_ops,
342 		.n_voltages = ARRAY_SIZE(ldo45_voltage_map),
343 		.type = REGULATOR_VOLTAGE,
344 		.owner = THIS_MODULE,
345 	},
346 	{
347 		.name = "DCDC1",
348 		.id = LP3971_DCDC1,
349 		.ops = &lp3971_dcdc_ops,
350 		.n_voltages = ARRAY_SIZE(buck_voltage_map),
351 		.type = REGULATOR_VOLTAGE,
352 		.owner = THIS_MODULE,
353 	},
354 	{
355 		.name = "DCDC2",
356 		.id = LP3971_DCDC2,
357 		.ops = &lp3971_dcdc_ops,
358 		.n_voltages = ARRAY_SIZE(buck_voltage_map),
359 		.type = REGULATOR_VOLTAGE,
360 		.owner = THIS_MODULE,
361 	},
362 	{
363 		.name = "DCDC3",
364 		.id = LP3971_DCDC3,
365 		.ops = &lp3971_dcdc_ops,
366 		.n_voltages = ARRAY_SIZE(buck_voltage_map),
367 		.type = REGULATOR_VOLTAGE,
368 		.owner = THIS_MODULE,
369 	},
370 };
371 
372 static int lp3971_i2c_read(struct i2c_client *i2c, char reg, int count,
373 	u16 *dest)
374 {
375 	int ret;
376 
377 	if (count != 1)
378 		return -EIO;
379 	ret = i2c_smbus_read_byte_data(i2c, reg);
380 	if (ret < 0)
381 		return -EIO;
382 
383 	*dest = ret;
384 	return 0;
385 }
386 
387 static int lp3971_i2c_write(struct i2c_client *i2c, char reg, int count,
388 	const u16 *src)
389 {
390 	if (count != 1)
391 		return -EIO;
392 	return i2c_smbus_write_byte_data(i2c, reg, *src);
393 }
394 
395 static u8 lp3971_reg_read(struct lp3971 *lp3971, u8 reg)
396 {
397 	u16 val = 0;
398 
399 	mutex_lock(&lp3971->io_lock);
400 
401 	lp3971_i2c_read(lp3971->i2c, reg, 1, &val);
402 
403 	dev_dbg(lp3971->dev, "reg read 0x%02x -> 0x%02x\n", (int)reg,
404 		(unsigned)val&0xff);
405 
406 	mutex_unlock(&lp3971->io_lock);
407 
408 	return val & 0xff;
409 }
410 
411 static int lp3971_set_bits(struct lp3971 *lp3971, u8 reg, u16 mask, u16 val)
412 {
413 	u16 tmp;
414 	int ret;
415 
416 	mutex_lock(&lp3971->io_lock);
417 
418 	ret = lp3971_i2c_read(lp3971->i2c, reg, 1, &tmp);
419 	tmp = (tmp & ~mask) | val;
420 	if (ret == 0) {
421 		ret = lp3971_i2c_write(lp3971->i2c, reg, 1, &tmp);
422 		dev_dbg(lp3971->dev, "reg write 0x%02x -> 0x%02x\n", (int)reg,
423 			(unsigned)val&0xff);
424 	}
425 	mutex_unlock(&lp3971->io_lock);
426 
427 	return ret;
428 }
429 
430 static int __devinit setup_regulators(struct lp3971 *lp3971,
431 				      struct lp3971_platform_data *pdata)
432 {
433 	int i, err;
434 
435 	lp3971->num_regulators = pdata->num_regulators;
436 	lp3971->rdev = kcalloc(pdata->num_regulators,
437 				sizeof(struct regulator_dev *), GFP_KERNEL);
438 	if (!lp3971->rdev) {
439 		err = -ENOMEM;
440 		goto err_nomem;
441 	}
442 
443 	/* Instantiate the regulators */
444 	for (i = 0; i < pdata->num_regulators; i++) {
445 		struct lp3971_regulator_subdev *reg = &pdata->regulators[i];
446 		lp3971->rdev[i] = regulator_register(&regulators[reg->id],
447 					lp3971->dev, reg->initdata, lp3971);
448 
449 		if (IS_ERR(lp3971->rdev[i])) {
450 			err = PTR_ERR(lp3971->rdev[i]);
451 			dev_err(lp3971->dev, "regulator init failed: %d\n",
452 				err);
453 			goto error;
454 		}
455 	}
456 
457 	return 0;
458 
459 error:
460 	while (--i >= 0)
461 		regulator_unregister(lp3971->rdev[i]);
462 	kfree(lp3971->rdev);
463 	lp3971->rdev = NULL;
464 err_nomem:
465 	return err;
466 }
467 
468 static int __devinit lp3971_i2c_probe(struct i2c_client *i2c,
469 			    const struct i2c_device_id *id)
470 {
471 	struct lp3971 *lp3971;
472 	struct lp3971_platform_data *pdata = i2c->dev.platform_data;
473 	int ret;
474 	u16 val;
475 
476 	if (!pdata) {
477 		dev_dbg(&i2c->dev, "No platform init data supplied\n");
478 		return -ENODEV;
479 	}
480 
481 	lp3971 = kzalloc(sizeof(struct lp3971), GFP_KERNEL);
482 	if (lp3971 == NULL)
483 		return -ENOMEM;
484 
485 	lp3971->i2c = i2c;
486 	lp3971->dev = &i2c->dev;
487 
488 	mutex_init(&lp3971->io_lock);
489 
490 	/* Detect LP3971 */
491 	ret = lp3971_i2c_read(i2c, LP3971_SYS_CONTROL1_REG, 1, &val);
492 	if (ret == 0 && (val & SYS_CONTROL1_INIT_MASK) != SYS_CONTROL1_INIT_VAL)
493 		ret = -ENODEV;
494 	if (ret < 0) {
495 		dev_err(&i2c->dev, "failed to detect device\n");
496 		goto err_detect;
497 	}
498 
499 	ret = setup_regulators(lp3971, pdata);
500 	if (ret < 0)
501 		goto err_detect;
502 
503 	i2c_set_clientdata(i2c, lp3971);
504 	return 0;
505 
506 err_detect:
507 	kfree(lp3971);
508 	return ret;
509 }
510 
511 static int __devexit lp3971_i2c_remove(struct i2c_client *i2c)
512 {
513 	struct lp3971 *lp3971 = i2c_get_clientdata(i2c);
514 	int i;
515 
516 	for (i = 0; i < lp3971->num_regulators; i++)
517 		regulator_unregister(lp3971->rdev[i]);
518 
519 	kfree(lp3971->rdev);
520 	kfree(lp3971);
521 
522 	return 0;
523 }
524 
525 static const struct i2c_device_id lp3971_i2c_id[] = {
526        { "lp3971", 0 },
527        { }
528 };
529 MODULE_DEVICE_TABLE(i2c, lp3971_i2c_id);
530 
531 static struct i2c_driver lp3971_i2c_driver = {
532 	.driver = {
533 		.name = "LP3971",
534 		.owner = THIS_MODULE,
535 	},
536 	.probe    = lp3971_i2c_probe,
537 	.remove   = __devexit_p(lp3971_i2c_remove),
538 	.id_table = lp3971_i2c_id,
539 };
540 
541 static int __init lp3971_module_init(void)
542 {
543 	int ret;
544 
545 	ret = i2c_add_driver(&lp3971_i2c_driver);
546 	if (ret != 0)
547 		pr_err("Failed to register I2C driver: %d\n", ret);
548 
549 	return ret;
550 }
551 module_init(lp3971_module_init);
552 
553 static void __exit lp3971_module_exit(void)
554 {
555 	i2c_del_driver(&lp3971_i2c_driver);
556 }
557 module_exit(lp3971_module_exit);
558 
559 MODULE_LICENSE("GPL");
560 MODULE_AUTHOR("Marek Szyprowski <m.szyprowski@samsung.com>");
561 MODULE_DESCRIPTION("LP3971 PMIC driver");
562