xref: /openbmc/linux/drivers/regulator/lp3971.c (revision 79f08d9e)
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 	int num_regulators;
29 	struct regulator_dev **rdev;
30 };
31 
32 static u8 lp3971_reg_read(struct lp3971 *lp3971, u8 reg);
33 static int lp3971_set_bits(struct lp3971 *lp3971, u8 reg, u16 mask, u16 val);
34 
35 #define LP3971_SYS_CONTROL1_REG 0x07
36 
37 /* System control register 1 initial value,
38    bits 4 and 5 are EPROM programmable */
39 #define SYS_CONTROL1_INIT_VAL 0x40
40 #define SYS_CONTROL1_INIT_MASK 0xCF
41 
42 #define LP3971_BUCK_VOL_ENABLE_REG 0x10
43 #define LP3971_BUCK_VOL_CHANGE_REG 0x20
44 
45 /*	Voltage control registers shift:
46 	LP3971_BUCK1 -> 0
47 	LP3971_BUCK2 -> 4
48 	LP3971_BUCK3 -> 6
49 */
50 #define BUCK_VOL_CHANGE_SHIFT(x) (((!!x) << 2) | (x & ~0x01))
51 #define BUCK_VOL_CHANGE_FLAG_GO 0x01
52 #define BUCK_VOL_CHANGE_FLAG_TARGET 0x02
53 #define BUCK_VOL_CHANGE_FLAG_MASK 0x03
54 
55 #define LP3971_BUCK1_BASE 0x23
56 #define LP3971_BUCK2_BASE 0x29
57 #define LP3971_BUCK3_BASE 0x32
58 
59 static const int buck_base_addr[] = {
60 	LP3971_BUCK1_BASE,
61 	LP3971_BUCK2_BASE,
62 	LP3971_BUCK3_BASE,
63 };
64 
65 #define LP3971_BUCK_TARGET_VOL1_REG(x) (buck_base_addr[x])
66 #define LP3971_BUCK_TARGET_VOL2_REG(x) (buck_base_addr[x]+1)
67 
68 static const unsigned int buck_voltage_map[] = {
69 	      0,  800000,  850000,  900000,  950000, 1000000, 1050000, 1100000,
70 	1150000, 1200000, 1250000, 1300000, 1350000, 1400000, 1450000, 1500000,
71 	1550000, 1600000, 1650000, 1700000, 1800000, 1900000, 2500000, 2800000,
72 	3000000, 3300000,
73 };
74 
75 #define BUCK_TARGET_VOL_MASK 0x3f
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 static const unsigned int ldo45_voltage_map[] = {
100 	1000000, 1050000, 1100000, 1150000, 1200000, 1250000, 1300000, 1350000,
101 	1400000, 1500000, 1800000, 1900000, 2500000, 2800000, 3000000, 3300000,
102 };
103 
104 static const unsigned int ldo123_voltage_map[] = {
105 	1800000, 1900000, 2000000, 2100000, 2200000, 2300000, 2400000, 2500000,
106 	2600000, 2700000, 2800000, 2900000, 3000000, 3100000, 3200000, 3300000,
107 };
108 
109 #define LDO_VOL_MIN_IDX 0x00
110 #define LDO_VOL_MAX_IDX 0x0f
111 
112 static int lp3971_ldo_is_enabled(struct regulator_dev *dev)
113 {
114 	struct lp3971 *lp3971 = rdev_get_drvdata(dev);
115 	int ldo = rdev_get_id(dev) - LP3971_LDO1;
116 	u16 mask = 1 << (1 + ldo);
117 	u16 val;
118 
119 	val = lp3971_reg_read(lp3971, LP3971_LDO_ENABLE_REG);
120 	return (val & mask) != 0;
121 }
122 
123 static int lp3971_ldo_enable(struct regulator_dev *dev)
124 {
125 	struct lp3971 *lp3971 = rdev_get_drvdata(dev);
126 	int ldo = rdev_get_id(dev) - LP3971_LDO1;
127 	u16 mask = 1 << (1 + ldo);
128 
129 	return lp3971_set_bits(lp3971, LP3971_LDO_ENABLE_REG, mask, mask);
130 }
131 
132 static int lp3971_ldo_disable(struct regulator_dev *dev)
133 {
134 	struct lp3971 *lp3971 = rdev_get_drvdata(dev);
135 	int ldo = rdev_get_id(dev) - LP3971_LDO1;
136 	u16 mask = 1 << (1 + ldo);
137 
138 	return lp3971_set_bits(lp3971, LP3971_LDO_ENABLE_REG, mask, 0);
139 }
140 
141 static int lp3971_ldo_get_voltage_sel(struct regulator_dev *dev)
142 {
143 	struct lp3971 *lp3971 = rdev_get_drvdata(dev);
144 	int ldo = rdev_get_id(dev) - LP3971_LDO1;
145 	u16 val, reg;
146 
147 	reg = lp3971_reg_read(lp3971, LP3971_LDO_VOL_CONTR_REG(ldo));
148 	val = (reg >> LDO_VOL_CONTR_SHIFT(ldo)) & LDO_VOL_CONTR_MASK;
149 
150 	return val;
151 }
152 
153 static int lp3971_ldo_set_voltage_sel(struct regulator_dev *dev,
154 				      unsigned int selector)
155 {
156 	struct lp3971 *lp3971 = rdev_get_drvdata(dev);
157 	int ldo = rdev_get_id(dev) - LP3971_LDO1;
158 
159 	return lp3971_set_bits(lp3971, LP3971_LDO_VOL_CONTR_REG(ldo),
160 			LDO_VOL_CONTR_MASK << LDO_VOL_CONTR_SHIFT(ldo),
161 			selector << LDO_VOL_CONTR_SHIFT(ldo));
162 }
163 
164 static struct regulator_ops lp3971_ldo_ops = {
165 	.list_voltage = regulator_list_voltage_table,
166 	.map_voltage = regulator_map_voltage_ascend,
167 	.is_enabled = lp3971_ldo_is_enabled,
168 	.enable = lp3971_ldo_enable,
169 	.disable = lp3971_ldo_disable,
170 	.get_voltage_sel = lp3971_ldo_get_voltage_sel,
171 	.set_voltage_sel = lp3971_ldo_set_voltage_sel,
172 };
173 
174 static int lp3971_dcdc_is_enabled(struct regulator_dev *dev)
175 {
176 	struct lp3971 *lp3971 = rdev_get_drvdata(dev);
177 	int buck = rdev_get_id(dev) - LP3971_DCDC1;
178 	u16 mask = 1 << (buck * 2);
179 	u16 val;
180 
181 	val = lp3971_reg_read(lp3971, LP3971_BUCK_VOL_ENABLE_REG);
182 	return (val & mask) != 0;
183 }
184 
185 static int lp3971_dcdc_enable(struct regulator_dev *dev)
186 {
187 	struct lp3971 *lp3971 = rdev_get_drvdata(dev);
188 	int buck = rdev_get_id(dev) - LP3971_DCDC1;
189 	u16 mask = 1 << (buck * 2);
190 
191 	return lp3971_set_bits(lp3971, LP3971_BUCK_VOL_ENABLE_REG, mask, mask);
192 }
193 
194 static int lp3971_dcdc_disable(struct regulator_dev *dev)
195 {
196 	struct lp3971 *lp3971 = rdev_get_drvdata(dev);
197 	int buck = rdev_get_id(dev) - LP3971_DCDC1;
198 	u16 mask = 1 << (buck * 2);
199 
200 	return lp3971_set_bits(lp3971, LP3971_BUCK_VOL_ENABLE_REG, mask, 0);
201 }
202 
203 static int lp3971_dcdc_get_voltage_sel(struct regulator_dev *dev)
204 {
205 	struct lp3971 *lp3971 = rdev_get_drvdata(dev);
206 	int buck = rdev_get_id(dev) - LP3971_DCDC1;
207 	u16 reg;
208 
209 	reg = lp3971_reg_read(lp3971, LP3971_BUCK_TARGET_VOL1_REG(buck));
210 	reg &= BUCK_TARGET_VOL_MASK;
211 
212 	return reg;
213 }
214 
215 static int lp3971_dcdc_set_voltage_sel(struct regulator_dev *dev,
216 				       unsigned int selector)
217 {
218 	struct lp3971 *lp3971 = rdev_get_drvdata(dev);
219 	int buck = rdev_get_id(dev) - LP3971_DCDC1;
220 	int ret;
221 
222 	ret = lp3971_set_bits(lp3971, LP3971_BUCK_TARGET_VOL1_REG(buck),
223 	       BUCK_TARGET_VOL_MASK, selector);
224 	if (ret)
225 		return ret;
226 
227 	ret = lp3971_set_bits(lp3971, LP3971_BUCK_VOL_CHANGE_REG,
228 	       BUCK_VOL_CHANGE_FLAG_MASK << BUCK_VOL_CHANGE_SHIFT(buck),
229 	       BUCK_VOL_CHANGE_FLAG_GO << BUCK_VOL_CHANGE_SHIFT(buck));
230 	if (ret)
231 		return ret;
232 
233 	return lp3971_set_bits(lp3971, LP3971_BUCK_VOL_CHANGE_REG,
234 	       BUCK_VOL_CHANGE_FLAG_MASK << BUCK_VOL_CHANGE_SHIFT(buck),
235 	       0 << BUCK_VOL_CHANGE_SHIFT(buck));
236 }
237 
238 static struct regulator_ops lp3971_dcdc_ops = {
239 	.list_voltage = regulator_list_voltage_table,
240 	.map_voltage = regulator_map_voltage_ascend,
241 	.is_enabled = lp3971_dcdc_is_enabled,
242 	.enable = lp3971_dcdc_enable,
243 	.disable = lp3971_dcdc_disable,
244 	.get_voltage_sel = lp3971_dcdc_get_voltage_sel,
245 	.set_voltage_sel = lp3971_dcdc_set_voltage_sel,
246 };
247 
248 static const struct regulator_desc regulators[] = {
249 	{
250 		.name = "LDO1",
251 		.id = LP3971_LDO1,
252 		.ops = &lp3971_ldo_ops,
253 		.n_voltages = ARRAY_SIZE(ldo123_voltage_map),
254 		.volt_table = ldo123_voltage_map,
255 		.type = REGULATOR_VOLTAGE,
256 		.owner = THIS_MODULE,
257 	},
258 	{
259 		.name = "LDO2",
260 		.id = LP3971_LDO2,
261 		.ops = &lp3971_ldo_ops,
262 		.n_voltages = ARRAY_SIZE(ldo123_voltage_map),
263 		.volt_table = ldo123_voltage_map,
264 		.type = REGULATOR_VOLTAGE,
265 		.owner = THIS_MODULE,
266 	},
267 	{
268 		.name = "LDO3",
269 		.id = LP3971_LDO3,
270 		.ops = &lp3971_ldo_ops,
271 		.n_voltages = ARRAY_SIZE(ldo123_voltage_map),
272 		.volt_table = ldo123_voltage_map,
273 		.type = REGULATOR_VOLTAGE,
274 		.owner = THIS_MODULE,
275 	},
276 	{
277 		.name = "LDO4",
278 		.id = LP3971_LDO4,
279 		.ops = &lp3971_ldo_ops,
280 		.n_voltages = ARRAY_SIZE(ldo45_voltage_map),
281 		.volt_table = ldo45_voltage_map,
282 		.type = REGULATOR_VOLTAGE,
283 		.owner = THIS_MODULE,
284 	},
285 	{
286 		.name = "LDO5",
287 		.id = LP3971_LDO5,
288 		.ops = &lp3971_ldo_ops,
289 		.n_voltages = ARRAY_SIZE(ldo45_voltage_map),
290 		.volt_table = ldo45_voltage_map,
291 		.type = REGULATOR_VOLTAGE,
292 		.owner = THIS_MODULE,
293 	},
294 	{
295 		.name = "DCDC1",
296 		.id = LP3971_DCDC1,
297 		.ops = &lp3971_dcdc_ops,
298 		.n_voltages = ARRAY_SIZE(buck_voltage_map),
299 		.volt_table = buck_voltage_map,
300 		.type = REGULATOR_VOLTAGE,
301 		.owner = THIS_MODULE,
302 	},
303 	{
304 		.name = "DCDC2",
305 		.id = LP3971_DCDC2,
306 		.ops = &lp3971_dcdc_ops,
307 		.n_voltages = ARRAY_SIZE(buck_voltage_map),
308 		.volt_table = buck_voltage_map,
309 		.type = REGULATOR_VOLTAGE,
310 		.owner = THIS_MODULE,
311 	},
312 	{
313 		.name = "DCDC3",
314 		.id = LP3971_DCDC3,
315 		.ops = &lp3971_dcdc_ops,
316 		.n_voltages = ARRAY_SIZE(buck_voltage_map),
317 		.volt_table = buck_voltage_map,
318 		.type = REGULATOR_VOLTAGE,
319 		.owner = THIS_MODULE,
320 	},
321 };
322 
323 static int lp3971_i2c_read(struct i2c_client *i2c, char reg, int count,
324 	u16 *dest)
325 {
326 	int ret;
327 
328 	if (count != 1)
329 		return -EIO;
330 	ret = i2c_smbus_read_byte_data(i2c, reg);
331 	if (ret < 0)
332 		return -EIO;
333 
334 	*dest = ret;
335 	return 0;
336 }
337 
338 static int lp3971_i2c_write(struct i2c_client *i2c, char reg, int count,
339 	const u16 *src)
340 {
341 	if (count != 1)
342 		return -EIO;
343 	return i2c_smbus_write_byte_data(i2c, reg, *src);
344 }
345 
346 static u8 lp3971_reg_read(struct lp3971 *lp3971, u8 reg)
347 {
348 	u16 val = 0;
349 
350 	mutex_lock(&lp3971->io_lock);
351 
352 	lp3971_i2c_read(lp3971->i2c, reg, 1, &val);
353 
354 	dev_dbg(lp3971->dev, "reg read 0x%02x -> 0x%02x\n", (int)reg,
355 		(unsigned)val&0xff);
356 
357 	mutex_unlock(&lp3971->io_lock);
358 
359 	return val & 0xff;
360 }
361 
362 static int lp3971_set_bits(struct lp3971 *lp3971, u8 reg, u16 mask, u16 val)
363 {
364 	u16 tmp;
365 	int ret;
366 
367 	mutex_lock(&lp3971->io_lock);
368 
369 	ret = lp3971_i2c_read(lp3971->i2c, reg, 1, &tmp);
370 	tmp = (tmp & ~mask) | val;
371 	if (ret == 0) {
372 		ret = lp3971_i2c_write(lp3971->i2c, reg, 1, &tmp);
373 		dev_dbg(lp3971->dev, "reg write 0x%02x -> 0x%02x\n", (int)reg,
374 			(unsigned)val&0xff);
375 	}
376 	mutex_unlock(&lp3971->io_lock);
377 
378 	return ret;
379 }
380 
381 static int setup_regulators(struct lp3971 *lp3971,
382 				      struct lp3971_platform_data *pdata)
383 {
384 	int i, err;
385 
386 	lp3971->num_regulators = pdata->num_regulators;
387 	lp3971->rdev = kcalloc(pdata->num_regulators,
388 				sizeof(struct regulator_dev *), GFP_KERNEL);
389 	if (!lp3971->rdev) {
390 		err = -ENOMEM;
391 		goto err_nomem;
392 	}
393 
394 	/* Instantiate the regulators */
395 	for (i = 0; i < pdata->num_regulators; i++) {
396 		struct regulator_config config = { };
397 		struct lp3971_regulator_subdev *reg = &pdata->regulators[i];
398 
399 		config.dev = lp3971->dev;
400 		config.init_data = reg->initdata;
401 		config.driver_data = lp3971;
402 
403 		lp3971->rdev[i] = regulator_register(&regulators[reg->id],
404 						     &config);
405 		if (IS_ERR(lp3971->rdev[i])) {
406 			err = PTR_ERR(lp3971->rdev[i]);
407 			dev_err(lp3971->dev, "regulator init failed: %d\n",
408 				err);
409 			goto error;
410 		}
411 	}
412 
413 	return 0;
414 
415 error:
416 	while (--i >= 0)
417 		regulator_unregister(lp3971->rdev[i]);
418 	kfree(lp3971->rdev);
419 	lp3971->rdev = NULL;
420 err_nomem:
421 	return err;
422 }
423 
424 static int lp3971_i2c_probe(struct i2c_client *i2c,
425 			    const struct i2c_device_id *id)
426 {
427 	struct lp3971 *lp3971;
428 	struct lp3971_platform_data *pdata = dev_get_platdata(&i2c->dev);
429 	int ret;
430 	u16 val;
431 
432 	if (!pdata) {
433 		dev_dbg(&i2c->dev, "No platform init data supplied\n");
434 		return -ENODEV;
435 	}
436 
437 	lp3971 = devm_kzalloc(&i2c->dev, sizeof(struct lp3971), GFP_KERNEL);
438 	if (lp3971 == NULL)
439 		return -ENOMEM;
440 
441 	lp3971->i2c = i2c;
442 	lp3971->dev = &i2c->dev;
443 
444 	mutex_init(&lp3971->io_lock);
445 
446 	/* Detect LP3971 */
447 	ret = lp3971_i2c_read(i2c, LP3971_SYS_CONTROL1_REG, 1, &val);
448 	if (ret == 0 && (val & SYS_CONTROL1_INIT_MASK) != SYS_CONTROL1_INIT_VAL)
449 		ret = -ENODEV;
450 	if (ret < 0) {
451 		dev_err(&i2c->dev, "failed to detect device\n");
452 		return ret;
453 	}
454 
455 	ret = setup_regulators(lp3971, pdata);
456 	if (ret < 0)
457 		return ret;
458 
459 	i2c_set_clientdata(i2c, lp3971);
460 	return 0;
461 }
462 
463 static int lp3971_i2c_remove(struct i2c_client *i2c)
464 {
465 	struct lp3971 *lp3971 = i2c_get_clientdata(i2c);
466 	int i;
467 
468 	for (i = 0; i < lp3971->num_regulators; i++)
469 		regulator_unregister(lp3971->rdev[i]);
470 
471 	kfree(lp3971->rdev);
472 
473 	return 0;
474 }
475 
476 static const struct i2c_device_id lp3971_i2c_id[] = {
477 	{ "lp3971", 0 },
478 	{ }
479 };
480 MODULE_DEVICE_TABLE(i2c, lp3971_i2c_id);
481 
482 static struct i2c_driver lp3971_i2c_driver = {
483 	.driver = {
484 		.name = "LP3971",
485 		.owner = THIS_MODULE,
486 	},
487 	.probe    = lp3971_i2c_probe,
488 	.remove   = lp3971_i2c_remove,
489 	.id_table = lp3971_i2c_id,
490 };
491 
492 module_i2c_driver(lp3971_i2c_driver);
493 
494 MODULE_LICENSE("GPL");
495 MODULE_AUTHOR("Marek Szyprowski <m.szyprowski@samsung.com>");
496 MODULE_DESCRIPTION("LP3971 PMIC driver");
497