xref: /openbmc/linux/drivers/regulator/lp3971.c (revision fd589a8f)
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 
22 struct lp3971 {
23 	struct device *dev;
24 	struct mutex io_lock;
25 	struct i2c_client *i2c;
26 	int num_regulators;
27 	struct regulator_dev **rdev;
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) (((1 << x) & ~0x01) << 1)
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 const static 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 const static int buck_voltage_map[] = {
67 	   0,  800,  850,  900,  950, 1000, 1050, 1100,
68 	1150, 1200, 1250, 1300, 1350, 1400, 1450, 1500,
69 	1550, 1600, 1650, 1700, 1800, 1900, 2500, 2800,
70 	3000, 3300,
71 };
72 
73 #define BUCK_TARGET_VOL_MASK 0x3f
74 #define BUCK_TARGET_VOL_MIN_IDX 0x01
75 #define BUCK_TARGET_VOL_MAX_IDX 0x19
76 
77 #define LP3971_BUCK_RAMP_REG(x)	(buck_base_addr[x]+2)
78 
79 #define LP3971_LDO_ENABLE_REG 0x12
80 #define LP3971_LDO_VOL_CONTR_BASE 0x39
81 
82 /*	Voltage control registers:
83 	LP3971_LDO1 -> LP3971_LDO_VOL_CONTR_BASE + 0
84 	LP3971_LDO2 -> LP3971_LDO_VOL_CONTR_BASE + 0
85 	LP3971_LDO3 -> LP3971_LDO_VOL_CONTR_BASE + 1
86 	LP3971_LDO4 -> LP3971_LDO_VOL_CONTR_BASE + 1
87 	LP3971_LDO5 -> LP3971_LDO_VOL_CONTR_BASE + 2
88 */
89 #define LP3971_LDO_VOL_CONTR_REG(x)	(LP3971_LDO_VOL_CONTR_BASE + (x >> 1))
90 
91 /*	Voltage control registers shift:
92 	LP3971_LDO1 -> 0, LP3971_LDO2 -> 4
93 	LP3971_LDO3 -> 0, LP3971_LDO4 -> 4
94 	LP3971_LDO5 -> 0
95 */
96 #define LDO_VOL_CONTR_SHIFT(x) ((x & 1) << 2)
97 #define LDO_VOL_CONTR_MASK 0x0f
98 
99 const static int ldo45_voltage_map[] = {
100 	1000, 1050, 1100, 1150, 1200, 1250, 1300, 1350,
101 	1400, 1500, 1800, 1900, 2500, 2800, 3000, 3300,
102 };
103 
104 const static int ldo123_voltage_map[] = {
105 	1800, 1900, 2000, 2100, 2200, 2300, 2400, 2500,
106 	2600, 2700, 2800, 2900, 3000, 3100, 3200, 3300,
107 };
108 
109 const static int *ldo_voltage_map[] = {
110 	ldo123_voltage_map, /* LDO1 */
111 	ldo123_voltage_map, /* LDO2 */
112 	ldo123_voltage_map, /* LDO3 */
113 	ldo45_voltage_map, /* LDO4 */
114 	ldo45_voltage_map, /* LDO5 */
115 };
116 
117 #define LDO_VOL_VALUE_MAP(x) (ldo_voltage_map[(x - LP3971_LDO1)])
118 
119 #define LDO_VOL_MIN_IDX 0x00
120 #define LDO_VOL_MAX_IDX 0x0f
121 
122 static int lp3971_ldo_list_voltage(struct regulator_dev *dev, unsigned index)
123 {
124 	int ldo = rdev_get_id(dev) - LP3971_LDO1;
125 	return 1000 * LDO_VOL_VALUE_MAP(ldo)[index];
126 }
127 
128 static int lp3971_ldo_is_enabled(struct regulator_dev *dev)
129 {
130 	struct lp3971 *lp3971 = rdev_get_drvdata(dev);
131 	int ldo = rdev_get_id(dev) - LP3971_LDO1;
132 	u16 mask = 1 << (1 + ldo);
133 	u16 val;
134 
135 	val = lp3971_reg_read(lp3971, LP3971_LDO_ENABLE_REG);
136 	return (val & mask) != 0;
137 }
138 
139 static int lp3971_ldo_enable(struct regulator_dev *dev)
140 {
141 	struct lp3971 *lp3971 = rdev_get_drvdata(dev);
142 	int ldo = rdev_get_id(dev) - LP3971_LDO1;
143 	u16 mask = 1 << (1 + ldo);
144 
145 	return lp3971_set_bits(lp3971, LP3971_LDO_ENABLE_REG, mask, mask);
146 }
147 
148 static int lp3971_ldo_disable(struct regulator_dev *dev)
149 {
150 	struct lp3971 *lp3971 = rdev_get_drvdata(dev);
151 	int ldo = rdev_get_id(dev) - LP3971_LDO1;
152 	u16 mask = 1 << (1 + ldo);
153 
154 	return lp3971_set_bits(lp3971, LP3971_LDO_ENABLE_REG, mask, 0);
155 }
156 
157 static int lp3971_ldo_get_voltage(struct regulator_dev *dev)
158 {
159 	struct lp3971 *lp3971 = rdev_get_drvdata(dev);
160 	int ldo = rdev_get_id(dev) - LP3971_LDO1;
161 	u16 val, reg;
162 
163 	reg = lp3971_reg_read(lp3971, LP3971_LDO_VOL_CONTR_REG(ldo));
164 	val = (reg >> LDO_VOL_CONTR_SHIFT(ldo)) & LDO_VOL_CONTR_MASK;
165 
166 	return 1000 * LDO_VOL_VALUE_MAP(ldo)[val];
167 }
168 
169 static int lp3971_ldo_set_voltage(struct regulator_dev *dev,
170 				  int min_uV, int max_uV)
171 {
172 	struct lp3971 *lp3971 = rdev_get_drvdata(dev);
173 	int ldo = rdev_get_id(dev) - LP3971_LDO1;
174 	int min_vol = min_uV / 1000, max_vol = max_uV / 1000;
175 	const int *vol_map = LDO_VOL_VALUE_MAP(ldo);
176 	u16 val;
177 
178 	if (min_vol < vol_map[LDO_VOL_MIN_IDX] ||
179 	    min_vol > vol_map[LDO_VOL_MAX_IDX])
180 		return -EINVAL;
181 
182 	for (val = LDO_VOL_MIN_IDX; val <= LDO_VOL_MAX_IDX; val++)
183 		if (vol_map[val] >= min_vol)
184 			break;
185 
186 	if (vol_map[val] > max_vol)
187 		return -EINVAL;
188 
189 	return lp3971_set_bits(lp3971, LP3971_LDO_VOL_CONTR_REG(ldo),
190 		LDO_VOL_CONTR_MASK << LDO_VOL_CONTR_SHIFT(ldo), val);
191 }
192 
193 static struct regulator_ops lp3971_ldo_ops = {
194 	.list_voltage = lp3971_ldo_list_voltage,
195 	.is_enabled = lp3971_ldo_is_enabled,
196 	.enable = lp3971_ldo_enable,
197 	.disable = lp3971_ldo_disable,
198 	.get_voltage = lp3971_ldo_get_voltage,
199 	.set_voltage = lp3971_ldo_set_voltage,
200 };
201 
202 static int lp3971_dcdc_list_voltage(struct regulator_dev *dev, unsigned index)
203 {
204 	return 1000 * buck_voltage_map[index];
205 }
206 
207 static int lp3971_dcdc_is_enabled(struct regulator_dev *dev)
208 {
209 	struct lp3971 *lp3971 = rdev_get_drvdata(dev);
210 	int buck = rdev_get_id(dev) - LP3971_DCDC1;
211 	u16 mask = 1 << (buck * 2);
212 	u16 val;
213 
214 	val = lp3971_reg_read(lp3971, LP3971_BUCK_VOL_ENABLE_REG);
215 	return (val & mask) != 0;
216 }
217 
218 static int lp3971_dcdc_enable(struct regulator_dev *dev)
219 {
220 	struct lp3971 *lp3971 = rdev_get_drvdata(dev);
221 	int buck = rdev_get_id(dev) - LP3971_DCDC1;
222 	u16 mask = 1 << (buck * 2);
223 
224 	return lp3971_set_bits(lp3971, LP3971_BUCK_VOL_ENABLE_REG, mask, mask);
225 }
226 
227 static int lp3971_dcdc_disable(struct regulator_dev *dev)
228 {
229 	struct lp3971 *lp3971 = rdev_get_drvdata(dev);
230 	int buck = rdev_get_id(dev) - LP3971_DCDC1;
231 	u16 mask = 1 << (buck * 2);
232 
233 	return lp3971_set_bits(lp3971, LP3971_BUCK_VOL_ENABLE_REG, mask, 0);
234 }
235 
236 static int lp3971_dcdc_get_voltage(struct regulator_dev *dev)
237 {
238 	struct lp3971 *lp3971 = rdev_get_drvdata(dev);
239 	int buck = rdev_get_id(dev) - LP3971_DCDC1;
240 	u16 reg;
241 	int val;
242 
243 	reg = lp3971_reg_read(lp3971, LP3971_BUCK_TARGET_VOL1_REG(buck));
244 	reg &= BUCK_TARGET_VOL_MASK;
245 
246 	if (reg <= BUCK_TARGET_VOL_MAX_IDX)
247 		val = 1000 * buck_voltage_map[reg];
248 	else {
249 		val = 0;
250 		dev_warn(&dev->dev, "chip reported incorrect voltage value.\n");
251 	}
252 
253 	return val;
254 }
255 
256 static int lp3971_dcdc_set_voltage(struct regulator_dev *dev,
257 				  int min_uV, int max_uV)
258 {
259 	struct lp3971 *lp3971 = rdev_get_drvdata(dev);
260 	int buck = rdev_get_id(dev) - LP3971_DCDC1;
261 	int min_vol = min_uV / 1000, max_vol = max_uV / 1000;
262 	const int *vol_map = buck_voltage_map;
263 	u16 val;
264 	int ret;
265 
266 	if (min_vol < vol_map[BUCK_TARGET_VOL_MIN_IDX] ||
267 	    min_vol > vol_map[BUCK_TARGET_VOL_MAX_IDX])
268 		return -EINVAL;
269 
270 	for (val = BUCK_TARGET_VOL_MIN_IDX; val <= BUCK_TARGET_VOL_MAX_IDX;
271 	     val++)
272 		if (vol_map[val] >= min_vol)
273 			break;
274 
275 	if (vol_map[val] > max_vol)
276 		return -EINVAL;
277 
278 	ret = lp3971_set_bits(lp3971, LP3971_BUCK_TARGET_VOL1_REG(buck),
279 	       BUCK_TARGET_VOL_MASK, val);
280 	if (ret)
281 		return ret;
282 
283 	ret = lp3971_set_bits(lp3971, LP3971_BUCK_VOL_CHANGE_REG,
284 	       BUCK_VOL_CHANGE_FLAG_MASK << BUCK_VOL_CHANGE_SHIFT(buck),
285 	       BUCK_VOL_CHANGE_FLAG_GO << BUCK_VOL_CHANGE_SHIFT(buck));
286 	if (ret)
287 		return ret;
288 
289 	return lp3971_set_bits(lp3971, LP3971_BUCK_VOL_CHANGE_REG,
290 	       BUCK_VOL_CHANGE_FLAG_MASK << BUCK_VOL_CHANGE_SHIFT(buck),
291 	       0 << BUCK_VOL_CHANGE_SHIFT(buck));
292 }
293 
294 static struct regulator_ops lp3971_dcdc_ops = {
295 	.list_voltage = lp3971_dcdc_list_voltage,
296 	.is_enabled = lp3971_dcdc_is_enabled,
297 	.enable = lp3971_dcdc_enable,
298 	.disable = lp3971_dcdc_disable,
299 	.get_voltage = lp3971_dcdc_get_voltage,
300 	.set_voltage = lp3971_dcdc_set_voltage,
301 };
302 
303 static struct regulator_desc regulators[] = {
304 	{
305 		.name = "LDO1",
306 		.id = LP3971_LDO1,
307 		.ops = &lp3971_ldo_ops,
308 		.n_voltages = ARRAY_SIZE(ldo123_voltage_map),
309 		.type = REGULATOR_VOLTAGE,
310 		.owner = THIS_MODULE,
311 	},
312 	{
313 		.name = "LDO2",
314 		.id = LP3971_LDO2,
315 		.ops = &lp3971_ldo_ops,
316 		.n_voltages = ARRAY_SIZE(ldo123_voltage_map),
317 		.type = REGULATOR_VOLTAGE,
318 		.owner = THIS_MODULE,
319 	},
320 	{
321 		.name = "LDO3",
322 		.id = LP3971_LDO3,
323 		.ops = &lp3971_ldo_ops,
324 		.n_voltages = ARRAY_SIZE(ldo123_voltage_map),
325 		.type = REGULATOR_VOLTAGE,
326 		.owner = THIS_MODULE,
327 	},
328 	{
329 		.name = "LDO4",
330 		.id = LP3971_LDO4,
331 		.ops = &lp3971_ldo_ops,
332 		.n_voltages = ARRAY_SIZE(ldo45_voltage_map),
333 		.type = REGULATOR_VOLTAGE,
334 		.owner = THIS_MODULE,
335 	},
336 	{
337 		.name = "LDO5",
338 		.id = LP3971_LDO5,
339 		.ops = &lp3971_ldo_ops,
340 		.n_voltages = ARRAY_SIZE(ldo45_voltage_map),
341 		.type = REGULATOR_VOLTAGE,
342 		.owner = THIS_MODULE,
343 	},
344 	{
345 		.name = "DCDC1",
346 		.id = LP3971_DCDC1,
347 		.ops = &lp3971_dcdc_ops,
348 		.n_voltages = ARRAY_SIZE(buck_voltage_map),
349 		.type = REGULATOR_VOLTAGE,
350 		.owner = THIS_MODULE,
351 	},
352 	{
353 		.name = "DCDC2",
354 		.id = LP3971_DCDC2,
355 		.ops = &lp3971_dcdc_ops,
356 		.n_voltages = ARRAY_SIZE(buck_voltage_map),
357 		.type = REGULATOR_VOLTAGE,
358 		.owner = THIS_MODULE,
359 	},
360 	{
361 		.name = "DCDC3",
362 		.id = LP3971_DCDC3,
363 		.ops = &lp3971_dcdc_ops,
364 		.n_voltages = ARRAY_SIZE(buck_voltage_map),
365 		.type = REGULATOR_VOLTAGE,
366 		.owner = THIS_MODULE,
367 	},
368 };
369 
370 static int lp3971_i2c_read(struct i2c_client *i2c, char reg, int count,
371 	u16 *dest)
372 {
373 	int ret;
374 
375 	if (count != 1)
376 		return -EIO;
377 	ret = i2c_smbus_read_byte_data(i2c, reg);
378 	if (ret < 0 || count != 1)
379 		return -EIO;
380 
381 	*dest = ret;
382 	return 0;
383 }
384 
385 static int lp3971_i2c_write(struct i2c_client *i2c, char reg, int count,
386 	const u16 *src)
387 {
388 	int ret;
389 
390 	if (count != 1)
391 		return -EIO;
392 	ret = i2c_smbus_write_byte_data(i2c, reg, *src);
393 	if (ret >= 0)
394 		return 0;
395 
396 	return ret;
397 }
398 
399 static u8 lp3971_reg_read(struct lp3971 *lp3971, u8 reg)
400 {
401 	u16 val = 0;
402 
403 	mutex_lock(&lp3971->io_lock);
404 
405 	lp3971_i2c_read(lp3971->i2c, reg, 1, &val);
406 
407 	dev_dbg(lp3971->dev, "reg read 0x%02x -> 0x%02x\n", (int)reg,
408 		(unsigned)val&0xff);
409 
410 	mutex_unlock(&lp3971->io_lock);
411 
412 	return val & 0xff;
413 }
414 
415 static int lp3971_set_bits(struct lp3971 *lp3971, u8 reg, u16 mask, u16 val)
416 {
417 	u16 tmp;
418 	int ret;
419 
420 	mutex_lock(&lp3971->io_lock);
421 
422 	ret = lp3971_i2c_read(lp3971->i2c, reg, 1, &tmp);
423 	tmp = (tmp & ~mask) | val;
424 	if (ret == 0) {
425 		ret = lp3971_i2c_write(lp3971->i2c, reg, 1, &tmp);
426 		dev_dbg(lp3971->dev, "reg write 0x%02x -> 0x%02x\n", (int)reg,
427 			(unsigned)val&0xff);
428 	}
429 	mutex_unlock(&lp3971->io_lock);
430 
431 	return ret;
432 }
433 
434 static int setup_regulators(struct lp3971 *lp3971,
435 	struct lp3971_platform_data *pdata)
436 {
437 	int i, err;
438 	int num_regulators = pdata->num_regulators;
439 	lp3971->num_regulators = num_regulators;
440 	lp3971->rdev = kzalloc(sizeof(struct regulator_dev *) * num_regulators,
441 		GFP_KERNEL);
442 
443 	/* Instantiate the regulators */
444 	for (i = 0; i < num_regulators; i++) {
445 		int id = pdata->regulators[i].id;
446 		lp3971->rdev[i] = regulator_register(&regulators[id],
447 			lp3971->dev, pdata->regulators[i].initdata, lp3971);
448 
449 		err = IS_ERR(lp3971->rdev[i]);
450 		if (err) {
451 			dev_err(lp3971->dev, "regulator init failed: %d\n",
452 				err);
453 			goto error;
454 		}
455 	}
456 
457 	return 0;
458 error:
459 	for (i = 0; i < num_regulators; i++)
460 		if (lp3971->rdev[i])
461 			regulator_unregister(lp3971->rdev[i]);
462 	kfree(lp3971->rdev);
463 	lp3971->rdev = NULL;
464 	return err;
465 }
466 
467 static int __devinit lp3971_i2c_probe(struct i2c_client *i2c,
468 			    const struct i2c_device_id *id)
469 {
470 	struct lp3971 *lp3971;
471 	struct lp3971_platform_data *pdata = i2c->dev.platform_data;
472 	int ret;
473 	u16 val;
474 
475 	lp3971 = kzalloc(sizeof(struct lp3971), GFP_KERNEL);
476 	if (lp3971 == NULL) {
477 		ret = -ENOMEM;
478 		goto err;
479 	}
480 
481 	lp3971->i2c = i2c;
482 	lp3971->dev = &i2c->dev;
483 	i2c_set_clientdata(i2c, lp3971);
484 
485 	mutex_init(&lp3971->io_lock);
486 
487 	/* Detect LP3971 */
488 	ret = lp3971_i2c_read(i2c, LP3971_SYS_CONTROL1_REG, 1, &val);
489 	if (ret == 0 && (val & SYS_CONTROL1_INIT_MASK) != SYS_CONTROL1_INIT_VAL)
490 		ret = -ENODEV;
491 	if (ret < 0) {
492 		dev_err(&i2c->dev, "failed to detect device\n");
493 		goto err_detect;
494 	}
495 
496 	if (pdata) {
497 		ret = setup_regulators(lp3971, pdata);
498 		if (ret < 0)
499 			goto err_detect;
500 	} else
501 		dev_warn(lp3971->dev, "No platform init data supplied\n");
502 
503 	return 0;
504 
505 err_detect:
506 	i2c_set_clientdata(i2c, NULL);
507 	kfree(lp3971);
508 err:
509 	return ret;
510 }
511 
512 static int __devexit lp3971_i2c_remove(struct i2c_client *i2c)
513 {
514 	struct lp3971 *lp3971 = i2c_get_clientdata(i2c);
515 	int i;
516 	for (i = 0; i < lp3971->num_regulators; i++)
517 		if (lp3971->rdev[i])
518 			regulator_unregister(lp3971->rdev[i]);
519 	kfree(lp3971->rdev);
520 	i2c_set_clientdata(i2c, NULL);
521 	kfree(lp3971);
522 
523 	return 0;
524 }
525 
526 static const struct i2c_device_id lp3971_i2c_id[] = {
527        { "lp3971", 0 },
528        { }
529 };
530 MODULE_DEVICE_TABLE(i2c, lp3971_i2c_id);
531 
532 static struct i2c_driver lp3971_i2c_driver = {
533 	.driver = {
534 		.name = "LP3971",
535 		.owner = THIS_MODULE,
536 	},
537 	.probe    = lp3971_i2c_probe,
538 	.remove   = __devexit_p(lp3971_i2c_remove),
539 	.id_table = lp3971_i2c_id,
540 };
541 
542 static int __init lp3971_module_init(void)
543 {
544 	int ret = -ENODEV;
545 
546 	ret = i2c_add_driver(&lp3971_i2c_driver);
547 	if (ret != 0)
548 		pr_err("Failed to register I2C driver: %d\n", ret);
549 
550 	return ret;
551 }
552 module_init(lp3971_module_init);
553 
554 static void __exit lp3971_module_exit(void)
555 {
556 	i2c_del_driver(&lp3971_i2c_driver);
557 }
558 module_exit(lp3971_module_exit);
559 
560 MODULE_LICENSE("GPL");
561 MODULE_AUTHOR("Marek Szyprowski <m.szyprowski@samsung.com>");
562 MODULE_DESCRIPTION("LP3971 PMIC driver");
563