xref: /openbmc/linux/drivers/regulator/lp3971.c (revision 9d749629)
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 	.is_enabled = lp3971_ldo_is_enabled,
167 	.enable = lp3971_ldo_enable,
168 	.disable = lp3971_ldo_disable,
169 	.get_voltage_sel = lp3971_ldo_get_voltage_sel,
170 	.set_voltage_sel = lp3971_ldo_set_voltage_sel,
171 };
172 
173 static int lp3971_dcdc_is_enabled(struct regulator_dev *dev)
174 {
175 	struct lp3971 *lp3971 = rdev_get_drvdata(dev);
176 	int buck = rdev_get_id(dev) - LP3971_DCDC1;
177 	u16 mask = 1 << (buck * 2);
178 	u16 val;
179 
180 	val = lp3971_reg_read(lp3971, LP3971_BUCK_VOL_ENABLE_REG);
181 	return (val & mask) != 0;
182 }
183 
184 static int lp3971_dcdc_enable(struct regulator_dev *dev)
185 {
186 	struct lp3971 *lp3971 = rdev_get_drvdata(dev);
187 	int buck = rdev_get_id(dev) - LP3971_DCDC1;
188 	u16 mask = 1 << (buck * 2);
189 
190 	return lp3971_set_bits(lp3971, LP3971_BUCK_VOL_ENABLE_REG, mask, mask);
191 }
192 
193 static int lp3971_dcdc_disable(struct regulator_dev *dev)
194 {
195 	struct lp3971 *lp3971 = rdev_get_drvdata(dev);
196 	int buck = rdev_get_id(dev) - LP3971_DCDC1;
197 	u16 mask = 1 << (buck * 2);
198 
199 	return lp3971_set_bits(lp3971, LP3971_BUCK_VOL_ENABLE_REG, mask, 0);
200 }
201 
202 static int lp3971_dcdc_get_voltage_sel(struct regulator_dev *dev)
203 {
204 	struct lp3971 *lp3971 = rdev_get_drvdata(dev);
205 	int buck = rdev_get_id(dev) - LP3971_DCDC1;
206 	u16 reg;
207 
208 	reg = lp3971_reg_read(lp3971, LP3971_BUCK_TARGET_VOL1_REG(buck));
209 	reg &= BUCK_TARGET_VOL_MASK;
210 
211 	return reg;
212 }
213 
214 static int lp3971_dcdc_set_voltage_sel(struct regulator_dev *dev,
215 				       unsigned int selector)
216 {
217 	struct lp3971 *lp3971 = rdev_get_drvdata(dev);
218 	int buck = rdev_get_id(dev) - LP3971_DCDC1;
219 	int ret;
220 
221 	ret = lp3971_set_bits(lp3971, LP3971_BUCK_TARGET_VOL1_REG(buck),
222 	       BUCK_TARGET_VOL_MASK, selector);
223 	if (ret)
224 		return ret;
225 
226 	ret = lp3971_set_bits(lp3971, LP3971_BUCK_VOL_CHANGE_REG,
227 	       BUCK_VOL_CHANGE_FLAG_MASK << BUCK_VOL_CHANGE_SHIFT(buck),
228 	       BUCK_VOL_CHANGE_FLAG_GO << BUCK_VOL_CHANGE_SHIFT(buck));
229 	if (ret)
230 		return ret;
231 
232 	return lp3971_set_bits(lp3971, LP3971_BUCK_VOL_CHANGE_REG,
233 	       BUCK_VOL_CHANGE_FLAG_MASK << BUCK_VOL_CHANGE_SHIFT(buck),
234 	       0 << BUCK_VOL_CHANGE_SHIFT(buck));
235 }
236 
237 static struct regulator_ops lp3971_dcdc_ops = {
238 	.list_voltage = regulator_list_voltage_table,
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 
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 -EIO;
331 
332 	*dest = ret;
333 	return 0;
334 }
335 
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 
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 
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 	tmp = (tmp & ~mask) | val;
369 	if (ret == 0) {
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 
379 static int setup_regulators(struct lp3971 *lp3971,
380 				      struct lp3971_platform_data *pdata)
381 {
382 	int i, err;
383 
384 	lp3971->num_regulators = pdata->num_regulators;
385 	lp3971->rdev = kcalloc(pdata->num_regulators,
386 				sizeof(struct regulator_dev *), GFP_KERNEL);
387 	if (!lp3971->rdev) {
388 		err = -ENOMEM;
389 		goto err_nomem;
390 	}
391 
392 	/* Instantiate the regulators */
393 	for (i = 0; i < pdata->num_regulators; i++) {
394 		struct regulator_config config = { };
395 		struct lp3971_regulator_subdev *reg = &pdata->regulators[i];
396 
397 		config.dev = lp3971->dev;
398 		config.init_data = reg->initdata;
399 		config.driver_data = lp3971;
400 
401 		lp3971->rdev[i] = regulator_register(&regulators[reg->id],
402 						     &config);
403 		if (IS_ERR(lp3971->rdev[i])) {
404 			err = PTR_ERR(lp3971->rdev[i]);
405 			dev_err(lp3971->dev, "regulator init failed: %d\n",
406 				err);
407 			goto error;
408 		}
409 	}
410 
411 	return 0;
412 
413 error:
414 	while (--i >= 0)
415 		regulator_unregister(lp3971->rdev[i]);
416 	kfree(lp3971->rdev);
417 	lp3971->rdev = NULL;
418 err_nomem:
419 	return err;
420 }
421 
422 static int lp3971_i2c_probe(struct i2c_client *i2c,
423 			    const struct i2c_device_id *id)
424 {
425 	struct lp3971 *lp3971;
426 	struct lp3971_platform_data *pdata = i2c->dev.platform_data;
427 	int ret;
428 	u16 val;
429 
430 	if (!pdata) {
431 		dev_dbg(&i2c->dev, "No platform init data supplied\n");
432 		return -ENODEV;
433 	}
434 
435 	lp3971 = kzalloc(sizeof(struct lp3971), GFP_KERNEL);
436 	if (lp3971 == NULL)
437 		return -ENOMEM;
438 
439 	lp3971->i2c = i2c;
440 	lp3971->dev = &i2c->dev;
441 
442 	mutex_init(&lp3971->io_lock);
443 
444 	/* Detect LP3971 */
445 	ret = lp3971_i2c_read(i2c, LP3971_SYS_CONTROL1_REG, 1, &val);
446 	if (ret == 0 && (val & SYS_CONTROL1_INIT_MASK) != SYS_CONTROL1_INIT_VAL)
447 		ret = -ENODEV;
448 	if (ret < 0) {
449 		dev_err(&i2c->dev, "failed to detect device\n");
450 		goto err_detect;
451 	}
452 
453 	ret = setup_regulators(lp3971, pdata);
454 	if (ret < 0)
455 		goto err_detect;
456 
457 	i2c_set_clientdata(i2c, lp3971);
458 	return 0;
459 
460 err_detect:
461 	kfree(lp3971);
462 	return ret;
463 }
464 
465 static int lp3971_i2c_remove(struct i2c_client *i2c)
466 {
467 	struct lp3971 *lp3971 = i2c_get_clientdata(i2c);
468 	int i;
469 
470 	for (i = 0; i < lp3971->num_regulators; i++)
471 		regulator_unregister(lp3971->rdev[i]);
472 
473 	kfree(lp3971->rdev);
474 	kfree(lp3971);
475 
476 	return 0;
477 }
478 
479 static const struct i2c_device_id lp3971_i2c_id[] = {
480        { "lp3971", 0 },
481        { }
482 };
483 MODULE_DEVICE_TABLE(i2c, lp3971_i2c_id);
484 
485 static struct i2c_driver lp3971_i2c_driver = {
486 	.driver = {
487 		.name = "LP3971",
488 		.owner = THIS_MODULE,
489 	},
490 	.probe    = lp3971_i2c_probe,
491 	.remove   = lp3971_i2c_remove,
492 	.id_table = lp3971_i2c_id,
493 };
494 
495 module_i2c_driver(lp3971_i2c_driver);
496 
497 MODULE_LICENSE("GPL");
498 MODULE_AUTHOR("Marek Szyprowski <m.szyprowski@samsung.com>");
499 MODULE_DESCRIPTION("LP3971 PMIC driver");
500