xref: /openbmc/linux/drivers/regulator/lp8755.c (revision ee89bd6b)
1 /*
2  * LP8755 High Performance Power Management Unit : System Interface Driver
3  * (based on rev. 0.26)
4  * Copyright 2012 Texas Instruments
5  *
6  * Author: Daniel(Geon Si) Jeong <daniel.jeong@ti.com>
7  *
8  * This program is free software; you can redistribute it and/or modify
9  * it under the terms of the GNU General Public License version 2 as
10  * published by the Free Software Foundation.
11  *
12  */
13 
14 #include <linux/module.h>
15 #include <linux/slab.h>
16 #include <linux/i2c.h>
17 #include <linux/err.h>
18 #include <linux/irq.h>
19 #include <linux/interrupt.h>
20 #include <linux/gpio.h>
21 #include <linux/regmap.h>
22 #include <linux/delay.h>
23 #include <linux/uaccess.h>
24 #include <linux/regulator/driver.h>
25 #include <linux/regulator/machine.h>
26 #include <linux/platform_data/lp8755.h>
27 
28 #define LP8755_REG_BUCK0	0x00
29 #define LP8755_REG_BUCK1	0x03
30 #define LP8755_REG_BUCK2	0x04
31 #define LP8755_REG_BUCK3	0x01
32 #define LP8755_REG_BUCK4	0x05
33 #define LP8755_REG_BUCK5	0x02
34 #define LP8755_REG_MAX		0xFF
35 
36 #define LP8755_BUCK_EN_M	BIT(7)
37 #define LP8755_BUCK_LINEAR_OUT_MAX	0x76
38 #define LP8755_BUCK_VOUT_M	0x7F
39 
40 struct lp8755_mphase {
41 	int nreg;
42 	int buck_num[LP8755_BUCK_MAX];
43 };
44 
45 struct lp8755_chip {
46 	struct device *dev;
47 	struct regmap *regmap;
48 	struct lp8755_platform_data *pdata;
49 
50 	int irq;
51 	unsigned int irqmask;
52 
53 	int mphase;
54 	struct regulator_dev *rdev[LP8755_BUCK_MAX];
55 };
56 
57 /**
58  *lp8755_read : read a single register value from lp8755.
59  *@pchip : device to read from
60  *@reg   : register to read from
61  *@val   : pointer to store read value
62  */
63 static int lp8755_read(struct lp8755_chip *pchip, unsigned int reg,
64 		       unsigned int *val)
65 {
66 	return regmap_read(pchip->regmap, reg, val);
67 }
68 
69 /**
70  *lp8755_write : write a single register value to lp8755.
71  *@pchip : device to write to
72  *@reg   : register to write to
73  *@val   : value to be written
74  */
75 static int lp8755_write(struct lp8755_chip *pchip, unsigned int reg,
76 			unsigned int val)
77 {
78 	return regmap_write(pchip->regmap, reg, val);
79 }
80 
81 /**
82  *lp8755_update_bits : set the values of bit fields in lp8755 register.
83  *@pchip : device to read from
84  *@reg   : register to update
85  *@mask  : bitmask to be changed
86  *@val   : value for bitmask
87  */
88 static int lp8755_update_bits(struct lp8755_chip *pchip, unsigned int reg,
89 			      unsigned int mask, unsigned int val)
90 {
91 	return regmap_update_bits(pchip->regmap, reg, mask, val);
92 }
93 
94 static int lp8755_buck_enable_time(struct regulator_dev *rdev)
95 {
96 	int ret;
97 	unsigned int regval;
98 	enum lp8755_bucks id = rdev_get_id(rdev);
99 	struct lp8755_chip *pchip = rdev_get_drvdata(rdev);
100 
101 	ret = lp8755_read(pchip, 0x12 + id, &regval);
102 	if (ret < 0) {
103 		dev_err(pchip->dev, "i2c acceess error %s\n", __func__);
104 		return ret;
105 	}
106 	return (regval & 0xff) * 100;
107 }
108 
109 static int lp8755_buck_set_mode(struct regulator_dev *rdev, unsigned int mode)
110 {
111 	int ret;
112 	unsigned int regbval = 0x0;
113 	enum lp8755_bucks id = rdev_get_id(rdev);
114 	struct lp8755_chip *pchip = rdev_get_drvdata(rdev);
115 
116 	switch (mode) {
117 	case REGULATOR_MODE_FAST:
118 		/* forced pwm mode */
119 		regbval = (0x01 << id);
120 		break;
121 	case REGULATOR_MODE_NORMAL:
122 		/* enable automatic pwm/pfm mode */
123 		ret = lp8755_update_bits(pchip, 0x08 + id, 0x20, 0x00);
124 		if (ret < 0)
125 			goto err_i2c;
126 		break;
127 	case REGULATOR_MODE_IDLE:
128 		/* enable automatic pwm/pfm/lppfm mode */
129 		ret = lp8755_update_bits(pchip, 0x08 + id, 0x20, 0x20);
130 		if (ret < 0)
131 			goto err_i2c;
132 
133 		ret = lp8755_update_bits(pchip, 0x10, 0x01, 0x01);
134 		if (ret < 0)
135 			goto err_i2c;
136 		break;
137 	default:
138 		dev_err(pchip->dev, "Not supported buck mode %s\n", __func__);
139 		/* forced pwm mode */
140 		regbval = (0x01 << id);
141 	}
142 
143 	ret = lp8755_update_bits(pchip, 0x06, 0x01 << id, regbval);
144 	if (ret < 0)
145 		goto err_i2c;
146 	return ret;
147 err_i2c:
148 	dev_err(pchip->dev, "i2c acceess error %s\n", __func__);
149 	return ret;
150 }
151 
152 static unsigned int lp8755_buck_get_mode(struct regulator_dev *rdev)
153 {
154 	int ret;
155 	unsigned int regval;
156 	enum lp8755_bucks id = rdev_get_id(rdev);
157 	struct lp8755_chip *pchip = rdev_get_drvdata(rdev);
158 
159 	ret = lp8755_read(pchip, 0x06, &regval);
160 	if (ret < 0)
161 		goto err_i2c;
162 
163 	/* mode fast means forced pwm mode */
164 	if (regval & (0x01 << id))
165 		return REGULATOR_MODE_FAST;
166 
167 	ret = lp8755_read(pchip, 0x08 + id, &regval);
168 	if (ret < 0)
169 		goto err_i2c;
170 
171 	/* mode idle means automatic pwm/pfm/lppfm mode */
172 	if (regval & 0x20)
173 		return REGULATOR_MODE_IDLE;
174 
175 	/* mode normal means automatic pwm/pfm mode */
176 	return REGULATOR_MODE_NORMAL;
177 
178 err_i2c:
179 	dev_err(pchip->dev, "i2c acceess error %s\n", __func__);
180 	return 0;
181 }
182 
183 static int lp8755_buck_set_ramp(struct regulator_dev *rdev, int ramp)
184 {
185 	int ret;
186 	unsigned int regval = 0x00;
187 	enum lp8755_bucks id = rdev_get_id(rdev);
188 	struct lp8755_chip *pchip = rdev_get_drvdata(rdev);
189 
190 	/* uV/us */
191 	switch (ramp) {
192 	case 0 ... 230:
193 		regval = 0x07;
194 		break;
195 	case 231 ... 470:
196 		regval = 0x06;
197 		break;
198 	case 471 ... 940:
199 		regval = 0x05;
200 		break;
201 	case 941 ... 1900:
202 		regval = 0x04;
203 		break;
204 	case 1901 ... 3800:
205 		regval = 0x03;
206 		break;
207 	case 3801 ... 7500:
208 		regval = 0x02;
209 		break;
210 	case 7501 ... 15000:
211 		regval = 0x01;
212 		break;
213 	case 15001 ... 30000:
214 		regval = 0x00;
215 		break;
216 	default:
217 		dev_err(pchip->dev,
218 			"Not supported ramp value %d %s\n", ramp, __func__);
219 		return -EINVAL;
220 	}
221 
222 	ret = lp8755_update_bits(pchip, 0x07 + id, 0x07, regval);
223 	if (ret < 0)
224 		goto err_i2c;
225 	return ret;
226 err_i2c:
227 	dev_err(pchip->dev, "i2c acceess error %s\n", __func__);
228 	return ret;
229 }
230 
231 static struct regulator_ops lp8755_buck_ops = {
232 	.list_voltage = regulator_list_voltage_linear,
233 	.set_voltage_sel = regulator_set_voltage_sel_regmap,
234 	.get_voltage_sel = regulator_get_voltage_sel_regmap,
235 	.enable = regulator_enable_regmap,
236 	.disable = regulator_disable_regmap,
237 	.is_enabled = regulator_is_enabled_regmap,
238 	.enable_time = lp8755_buck_enable_time,
239 	.set_mode = lp8755_buck_set_mode,
240 	.get_mode = lp8755_buck_get_mode,
241 	.set_ramp_delay = lp8755_buck_set_ramp,
242 };
243 
244 #define lp8755_rail(_id) "lp8755_buck"#_id
245 #define lp8755_buck_init(_id)\
246 {\
247 	.constraints = {\
248 		.name = lp8755_rail(_id),\
249 		.valid_ops_mask = REGULATOR_CHANGE_VOLTAGE,\
250 		.min_uV = 500000,\
251 		.max_uV = 1675000,\
252 	},\
253 }
254 
255 static struct regulator_init_data lp8755_reg_default[LP8755_BUCK_MAX] = {
256 	[LP8755_BUCK0] = lp8755_buck_init(0),
257 	[LP8755_BUCK1] = lp8755_buck_init(1),
258 	[LP8755_BUCK2] = lp8755_buck_init(2),
259 	[LP8755_BUCK3] = lp8755_buck_init(3),
260 	[LP8755_BUCK4] = lp8755_buck_init(4),
261 	[LP8755_BUCK5] = lp8755_buck_init(5),
262 };
263 
264 static const struct lp8755_mphase mphase_buck[MPHASE_CONF_MAX] = {
265 	{ 3, { LP8755_BUCK0, LP8755_BUCK3, LP8755_BUCK5 } },
266 	{ 6, { LP8755_BUCK0, LP8755_BUCK1, LP8755_BUCK2, LP8755_BUCK3,
267 	       LP8755_BUCK4, LP8755_BUCK5 } },
268 	{ 5, { LP8755_BUCK0, LP8755_BUCK2, LP8755_BUCK3, LP8755_BUCK4,
269 	       LP8755_BUCK5} },
270 	{ 4, { LP8755_BUCK0, LP8755_BUCK3, LP8755_BUCK4, LP8755_BUCK5} },
271 	{ 3, { LP8755_BUCK0, LP8755_BUCK4, LP8755_BUCK5} },
272 	{ 2, { LP8755_BUCK0, LP8755_BUCK5} },
273 	{ 1, { LP8755_BUCK0} },
274 	{ 2, { LP8755_BUCK0, LP8755_BUCK3} },
275 	{ 4, { LP8755_BUCK0, LP8755_BUCK2, LP8755_BUCK3, LP8755_BUCK5} },
276 };
277 
278 static int lp8755_init_data(struct lp8755_chip *pchip)
279 {
280 	unsigned int regval;
281 	int ret, icnt, buck_num;
282 	struct lp8755_platform_data *pdata = pchip->pdata;
283 
284 	/* read back  muti-phase configuration */
285 	ret = lp8755_read(pchip, 0x3D, &regval);
286 	if (ret < 0)
287 		goto out_i2c_error;
288 	pchip->mphase = regval & 0x0F;
289 
290 	/* set default data based on multi-phase config */
291 	for (icnt = 0; icnt < mphase_buck[pchip->mphase].nreg; icnt++) {
292 		buck_num = mphase_buck[pchip->mphase].buck_num[icnt];
293 		pdata->buck_data[buck_num] = &lp8755_reg_default[buck_num];
294 	}
295 	return ret;
296 
297 out_i2c_error:
298 	dev_err(pchip->dev, "i2c acceess error %s\n", __func__);
299 	return ret;
300 }
301 
302 #define lp8755_buck_desc(_id)\
303 {\
304 	.name = lp8755_rail(_id),\
305 	.id   = LP8755_BUCK##_id,\
306 	.ops  = &lp8755_buck_ops,\
307 	.n_voltages = LP8755_BUCK_LINEAR_OUT_MAX+1,\
308 	.uV_step = 10000,\
309 	.min_uV = 500000,\
310 	.type = REGULATOR_VOLTAGE,\
311 	.owner = THIS_MODULE,\
312 	.enable_reg = LP8755_REG_BUCK##_id,\
313 	.enable_mask = LP8755_BUCK_EN_M,\
314 	.vsel_reg = LP8755_REG_BUCK##_id,\
315 	.vsel_mask = LP8755_BUCK_VOUT_M,\
316 }
317 
318 static struct regulator_desc lp8755_regulators[] = {
319 	lp8755_buck_desc(0),
320 	lp8755_buck_desc(1),
321 	lp8755_buck_desc(2),
322 	lp8755_buck_desc(3),
323 	lp8755_buck_desc(4),
324 	lp8755_buck_desc(5),
325 };
326 
327 static int lp8755_regulator_init(struct lp8755_chip *pchip)
328 {
329 	int ret, icnt, buck_num;
330 	struct lp8755_platform_data *pdata = pchip->pdata;
331 	struct regulator_config rconfig = { };
332 
333 	rconfig.regmap = pchip->regmap;
334 	rconfig.dev = pchip->dev;
335 	rconfig.driver_data = pchip;
336 
337 	for (icnt = 0; icnt < mphase_buck[pchip->mphase].nreg; icnt++) {
338 		buck_num = mphase_buck[pchip->mphase].buck_num[icnt];
339 		rconfig.init_data = pdata->buck_data[buck_num];
340 		rconfig.of_node = pchip->dev->of_node;
341 		pchip->rdev[buck_num] =
342 		    regulator_register(&lp8755_regulators[buck_num], &rconfig);
343 		if (IS_ERR(pchip->rdev[buck_num])) {
344 			ret = PTR_ERR(pchip->rdev[buck_num]);
345 			pchip->rdev[buck_num] = NULL;
346 			dev_err(pchip->dev, "regulator init failed: buck %d\n",
347 				buck_num);
348 			goto err_buck;
349 		}
350 	}
351 
352 	return 0;
353 
354 err_buck:
355 	for (icnt = 0; icnt < LP8755_BUCK_MAX; icnt++)
356 		regulator_unregister(pchip->rdev[icnt]);
357 	return ret;
358 }
359 
360 static irqreturn_t lp8755_irq_handler(int irq, void *data)
361 {
362 	int ret, icnt;
363 	unsigned int flag0, flag1;
364 	struct lp8755_chip *pchip = data;
365 
366 	/* read flag0 register */
367 	ret = lp8755_read(pchip, 0x0D, &flag0);
368 	if (ret < 0)
369 		goto err_i2c;
370 	/* clear flag register to pull up int. pin */
371 	ret = lp8755_write(pchip, 0x0D, 0x00);
372 	if (ret < 0)
373 		goto err_i2c;
374 
375 	/* sent power fault detection event to specific regulator */
376 	for (icnt = 0; icnt < LP8755_BUCK_MAX; icnt++)
377 		if ((flag0 & (0x4 << icnt))
378 		    && (pchip->irqmask & (0x04 << icnt))
379 		    && (pchip->rdev[icnt] != NULL))
380 			regulator_notifier_call_chain(pchip->rdev[icnt],
381 						      LP8755_EVENT_PWR_FAULT,
382 						      NULL);
383 
384 	/* read flag1 register */
385 	ret = lp8755_read(pchip, 0x0E, &flag1);
386 	if (ret < 0)
387 		goto err_i2c;
388 	/* clear flag register to pull up int. pin */
389 	ret = lp8755_write(pchip, 0x0E, 0x00);
390 	if (ret < 0)
391 		goto err_i2c;
392 
393 	/* send OCP event to all regualtor devices */
394 	if ((flag1 & 0x01) && (pchip->irqmask & 0x01))
395 		for (icnt = 0; icnt < LP8755_BUCK_MAX; icnt++)
396 			if (pchip->rdev[icnt] != NULL)
397 				regulator_notifier_call_chain(pchip->rdev[icnt],
398 							      LP8755_EVENT_OCP,
399 							      NULL);
400 
401 	/* send OVP event to all regualtor devices */
402 	if ((flag1 & 0x02) && (pchip->irqmask & 0x02))
403 		for (icnt = 0; icnt < LP8755_BUCK_MAX; icnt++)
404 			if (pchip->rdev[icnt] != NULL)
405 				regulator_notifier_call_chain(pchip->rdev[icnt],
406 							      LP8755_EVENT_OVP,
407 							      NULL);
408 	return IRQ_HANDLED;
409 
410 err_i2c:
411 	dev_err(pchip->dev, "i2c acceess error %s\n", __func__);
412 	return IRQ_NONE;
413 }
414 
415 static int lp8755_int_config(struct lp8755_chip *pchip)
416 {
417 	int ret;
418 	unsigned int regval;
419 
420 	if (pchip->irq == 0) {
421 		dev_warn(pchip->dev, "not use interrupt : %s\n", __func__);
422 		return 0;
423 	}
424 
425 	ret = lp8755_read(pchip, 0x0F, &regval);
426 	if (ret < 0)
427 		goto err_i2c;
428 	pchip->irqmask = regval;
429 	ret = request_threaded_irq(pchip->irq, NULL, lp8755_irq_handler,
430 				   IRQF_TRIGGER_FALLING | IRQF_ONESHOT,
431 				   "lp8755-irq", pchip);
432 	if (ret)
433 		return ret;
434 
435 	return ret;
436 
437 err_i2c:
438 	dev_err(pchip->dev, "i2c acceess error %s\n", __func__);
439 	return ret;
440 }
441 
442 static const struct regmap_config lp8755_regmap = {
443 	.reg_bits = 8,
444 	.val_bits = 8,
445 	.max_register = LP8755_REG_MAX,
446 };
447 
448 static int lp8755_probe(struct i2c_client *client,
449 			const struct i2c_device_id *id)
450 {
451 	int ret, icnt;
452 	struct lp8755_chip *pchip;
453 	struct lp8755_platform_data *pdata = client->dev.platform_data;
454 
455 	if (!i2c_check_functionality(client->adapter, I2C_FUNC_I2C)) {
456 		dev_err(&client->dev, "i2c functionality check fail.\n");
457 		return -EOPNOTSUPP;
458 	}
459 
460 	pchip = devm_kzalloc(&client->dev,
461 			     sizeof(struct lp8755_chip), GFP_KERNEL);
462 	if (!pchip)
463 		return -ENOMEM;
464 
465 	pchip->dev = &client->dev;
466 	pchip->regmap = devm_regmap_init_i2c(client, &lp8755_regmap);
467 	if (IS_ERR(pchip->regmap)) {
468 		ret = PTR_ERR(pchip->regmap);
469 		dev_err(&client->dev, "fail to allocate regmap %d\n", ret);
470 		return ret;
471 	}
472 	i2c_set_clientdata(client, pchip);
473 
474 	if (pdata != NULL) {
475 		pchip->pdata = pdata;
476 		pchip->mphase = pdata->mphase;
477 	} else {
478 		pchip->pdata = devm_kzalloc(pchip->dev,
479 					    sizeof(struct lp8755_platform_data),
480 					    GFP_KERNEL);
481 		if (!pchip->pdata)
482 			return -ENOMEM;
483 		ret = lp8755_init_data(pchip);
484 		if (ret < 0) {
485 			dev_err(&client->dev, "fail to initialize chip\n");
486 			return ret;
487 		}
488 	}
489 
490 	ret = lp8755_regulator_init(pchip);
491 	if (ret < 0) {
492 		dev_err(&client->dev, "fail to initialize regulators\n");
493 		goto err_regulator;
494 	}
495 
496 	pchip->irq = client->irq;
497 	ret = lp8755_int_config(pchip);
498 	if (ret < 0) {
499 		dev_err(&client->dev, "fail to irq config\n");
500 		goto err_irq;
501 	}
502 
503 	return ret;
504 
505 err_irq:
506 	for (icnt = 0; icnt < mphase_buck[pchip->mphase].nreg; icnt++)
507 		regulator_unregister(pchip->rdev[icnt]);
508 
509 err_regulator:
510 	/* output disable */
511 	for (icnt = 0; icnt < LP8755_BUCK_MAX; icnt++)
512 		lp8755_write(pchip, icnt, 0x00);
513 
514 	return ret;
515 }
516 
517 static int lp8755_remove(struct i2c_client *client)
518 {
519 	int icnt;
520 	struct lp8755_chip *pchip = i2c_get_clientdata(client);
521 
522 	for (icnt = 0; icnt < mphase_buck[pchip->mphase].nreg; icnt++)
523 		regulator_unregister(pchip->rdev[icnt]);
524 
525 	for (icnt = 0; icnt < LP8755_BUCK_MAX; icnt++)
526 		lp8755_write(pchip, icnt, 0x00);
527 
528 	if (pchip->irq != 0)
529 		free_irq(pchip->irq, pchip);
530 
531 	return 0;
532 }
533 
534 static const struct i2c_device_id lp8755_id[] = {
535 	{LP8755_NAME, 0},
536 	{}
537 };
538 
539 MODULE_DEVICE_TABLE(i2c, lp8755_id);
540 
541 static struct i2c_driver lp8755_i2c_driver = {
542 	.driver = {
543 		   .name = LP8755_NAME,
544 		   },
545 	.probe = lp8755_probe,
546 	.remove = lp8755_remove,
547 	.id_table = lp8755_id,
548 };
549 
550 static int __init lp8755_init(void)
551 {
552 	return i2c_add_driver(&lp8755_i2c_driver);
553 }
554 
555 subsys_initcall(lp8755_init);
556 
557 static void __exit lp8755_exit(void)
558 {
559 	i2c_del_driver(&lp8755_i2c_driver);
560 }
561 
562 module_exit(lp8755_exit);
563 
564 MODULE_DESCRIPTION("Texas Instruments lp8755 driver");
565 MODULE_AUTHOR("Daniel Jeong <daniel.jeong@ti.com>");
566 MODULE_LICENSE("GPL v2");
567