xref: /openbmc/linux/drivers/regulator/lp8755.c (revision b830f94f)
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * LP8755 High Performance Power Management Unit : System Interface Driver
4  * (based on rev. 0.26)
5  * Copyright 2012 Texas Instruments
6  *
7  * Author: Daniel(Geon Si) Jeong <daniel.jeong@ti.com>
8  */
9 
10 #include <linux/module.h>
11 #include <linux/slab.h>
12 #include <linux/i2c.h>
13 #include <linux/err.h>
14 #include <linux/irq.h>
15 #include <linux/interrupt.h>
16 #include <linux/gpio.h>
17 #include <linux/regmap.h>
18 #include <linux/uaccess.h>
19 #include <linux/regulator/driver.h>
20 #include <linux/regulator/machine.h>
21 #include <linux/platform_data/lp8755.h>
22 
23 #define LP8755_REG_BUCK0	0x00
24 #define LP8755_REG_BUCK1	0x03
25 #define LP8755_REG_BUCK2	0x04
26 #define LP8755_REG_BUCK3	0x01
27 #define LP8755_REG_BUCK4	0x05
28 #define LP8755_REG_BUCK5	0x02
29 #define LP8755_REG_MAX		0xFF
30 
31 #define LP8755_BUCK_EN_M	BIT(7)
32 #define LP8755_BUCK_LINEAR_OUT_MAX	0x76
33 #define LP8755_BUCK_VOUT_M	0x7F
34 
35 struct lp8755_mphase {
36 	int nreg;
37 	int buck_num[LP8755_BUCK_MAX];
38 };
39 
40 struct lp8755_chip {
41 	struct device *dev;
42 	struct regmap *regmap;
43 	struct lp8755_platform_data *pdata;
44 
45 	int irq;
46 	unsigned int irqmask;
47 
48 	int mphase;
49 	struct regulator_dev *rdev[LP8755_BUCK_MAX];
50 };
51 
52 /**
53  *lp8755_read : read a single register value from lp8755.
54  *@pchip : device to read from
55  *@reg   : register to read from
56  *@val   : pointer to store read value
57  */
58 static int lp8755_read(struct lp8755_chip *pchip, unsigned int reg,
59 		       unsigned int *val)
60 {
61 	return regmap_read(pchip->regmap, reg, val);
62 }
63 
64 /**
65  *lp8755_write : write a single register value to lp8755.
66  *@pchip : device to write to
67  *@reg   : register to write to
68  *@val   : value to be written
69  */
70 static int lp8755_write(struct lp8755_chip *pchip, unsigned int reg,
71 			unsigned int val)
72 {
73 	return regmap_write(pchip->regmap, reg, val);
74 }
75 
76 /**
77  *lp8755_update_bits : set the values of bit fields in lp8755 register.
78  *@pchip : device to read from
79  *@reg   : register to update
80  *@mask  : bitmask to be changed
81  *@val   : value for bitmask
82  */
83 static int lp8755_update_bits(struct lp8755_chip *pchip, unsigned int reg,
84 			      unsigned int mask, unsigned int val)
85 {
86 	return regmap_update_bits(pchip->regmap, reg, mask, val);
87 }
88 
89 static int lp8755_buck_enable_time(struct regulator_dev *rdev)
90 {
91 	int ret;
92 	unsigned int regval;
93 	enum lp8755_bucks id = rdev_get_id(rdev);
94 	struct lp8755_chip *pchip = rdev_get_drvdata(rdev);
95 
96 	ret = lp8755_read(pchip, 0x12 + id, &regval);
97 	if (ret < 0) {
98 		dev_err(pchip->dev, "i2c access error %s\n", __func__);
99 		return ret;
100 	}
101 	return (regval & 0xff) * 100;
102 }
103 
104 static int lp8755_buck_set_mode(struct regulator_dev *rdev, unsigned int mode)
105 {
106 	int ret;
107 	unsigned int regbval = 0x0;
108 	enum lp8755_bucks id = rdev_get_id(rdev);
109 	struct lp8755_chip *pchip = rdev_get_drvdata(rdev);
110 
111 	switch (mode) {
112 	case REGULATOR_MODE_FAST:
113 		/* forced pwm mode */
114 		regbval = (0x01 << id);
115 		break;
116 	case REGULATOR_MODE_NORMAL:
117 		/* enable automatic pwm/pfm mode */
118 		ret = lp8755_update_bits(pchip, 0x08 + id, 0x20, 0x00);
119 		if (ret < 0)
120 			goto err_i2c;
121 		break;
122 	case REGULATOR_MODE_IDLE:
123 		/* enable automatic pwm/pfm/lppfm mode */
124 		ret = lp8755_update_bits(pchip, 0x08 + id, 0x20, 0x20);
125 		if (ret < 0)
126 			goto err_i2c;
127 
128 		ret = lp8755_update_bits(pchip, 0x10, 0x01, 0x01);
129 		if (ret < 0)
130 			goto err_i2c;
131 		break;
132 	default:
133 		dev_err(pchip->dev, "Not supported buck mode %s\n", __func__);
134 		/* forced pwm mode */
135 		regbval = (0x01 << id);
136 	}
137 
138 	ret = lp8755_update_bits(pchip, 0x06, 0x01 << id, regbval);
139 	if (ret < 0)
140 		goto err_i2c;
141 	return ret;
142 err_i2c:
143 	dev_err(pchip->dev, "i2c access error %s\n", __func__);
144 	return ret;
145 }
146 
147 static unsigned int lp8755_buck_get_mode(struct regulator_dev *rdev)
148 {
149 	int ret;
150 	unsigned int regval;
151 	enum lp8755_bucks id = rdev_get_id(rdev);
152 	struct lp8755_chip *pchip = rdev_get_drvdata(rdev);
153 
154 	ret = lp8755_read(pchip, 0x06, &regval);
155 	if (ret < 0)
156 		goto err_i2c;
157 
158 	/* mode fast means forced pwm mode */
159 	if (regval & (0x01 << id))
160 		return REGULATOR_MODE_FAST;
161 
162 	ret = lp8755_read(pchip, 0x08 + id, &regval);
163 	if (ret < 0)
164 		goto err_i2c;
165 
166 	/* mode idle means automatic pwm/pfm/lppfm mode */
167 	if (regval & 0x20)
168 		return REGULATOR_MODE_IDLE;
169 
170 	/* mode normal means automatic pwm/pfm mode */
171 	return REGULATOR_MODE_NORMAL;
172 
173 err_i2c:
174 	dev_err(pchip->dev, "i2c access error %s\n", __func__);
175 	return 0;
176 }
177 
178 static int lp8755_buck_set_ramp(struct regulator_dev *rdev, int ramp)
179 {
180 	int ret;
181 	unsigned int regval = 0x00;
182 	enum lp8755_bucks id = rdev_get_id(rdev);
183 	struct lp8755_chip *pchip = rdev_get_drvdata(rdev);
184 
185 	/* uV/us */
186 	switch (ramp) {
187 	case 0 ... 230:
188 		regval = 0x07;
189 		break;
190 	case 231 ... 470:
191 		regval = 0x06;
192 		break;
193 	case 471 ... 940:
194 		regval = 0x05;
195 		break;
196 	case 941 ... 1900:
197 		regval = 0x04;
198 		break;
199 	case 1901 ... 3800:
200 		regval = 0x03;
201 		break;
202 	case 3801 ... 7500:
203 		regval = 0x02;
204 		break;
205 	case 7501 ... 15000:
206 		regval = 0x01;
207 		break;
208 	case 15001 ... 30000:
209 		regval = 0x00;
210 		break;
211 	default:
212 		dev_err(pchip->dev,
213 			"Not supported ramp value %d %s\n", ramp, __func__);
214 		return -EINVAL;
215 	}
216 
217 	ret = lp8755_update_bits(pchip, 0x07 + id, 0x07, regval);
218 	if (ret < 0)
219 		goto err_i2c;
220 	return ret;
221 err_i2c:
222 	dev_err(pchip->dev, "i2c access error %s\n", __func__);
223 	return ret;
224 }
225 
226 static const struct regulator_ops lp8755_buck_ops = {
227 	.map_voltage = regulator_map_voltage_linear,
228 	.list_voltage = regulator_list_voltage_linear,
229 	.set_voltage_sel = regulator_set_voltage_sel_regmap,
230 	.get_voltage_sel = regulator_get_voltage_sel_regmap,
231 	.enable = regulator_enable_regmap,
232 	.disable = regulator_disable_regmap,
233 	.is_enabled = regulator_is_enabled_regmap,
234 	.enable_time = lp8755_buck_enable_time,
235 	.set_mode = lp8755_buck_set_mode,
236 	.get_mode = lp8755_buck_get_mode,
237 	.set_ramp_delay = lp8755_buck_set_ramp,
238 };
239 
240 #define lp8755_rail(_id) "lp8755_buck"#_id
241 #define lp8755_buck_init(_id)\
242 {\
243 	.constraints = {\
244 		.name = lp8755_rail(_id),\
245 		.valid_ops_mask = REGULATOR_CHANGE_VOLTAGE,\
246 		.min_uV = 500000,\
247 		.max_uV = 1675000,\
248 	},\
249 }
250 
251 static struct regulator_init_data lp8755_reg_default[LP8755_BUCK_MAX] = {
252 	[LP8755_BUCK0] = lp8755_buck_init(0),
253 	[LP8755_BUCK1] = lp8755_buck_init(1),
254 	[LP8755_BUCK2] = lp8755_buck_init(2),
255 	[LP8755_BUCK3] = lp8755_buck_init(3),
256 	[LP8755_BUCK4] = lp8755_buck_init(4),
257 	[LP8755_BUCK5] = lp8755_buck_init(5),
258 };
259 
260 static const struct lp8755_mphase mphase_buck[MPHASE_CONF_MAX] = {
261 	{ 3, { LP8755_BUCK0, LP8755_BUCK3, LP8755_BUCK5 } },
262 	{ 6, { LP8755_BUCK0, LP8755_BUCK1, LP8755_BUCK2, LP8755_BUCK3,
263 	       LP8755_BUCK4, LP8755_BUCK5 } },
264 	{ 5, { LP8755_BUCK0, LP8755_BUCK2, LP8755_BUCK3, LP8755_BUCK4,
265 	       LP8755_BUCK5} },
266 	{ 4, { LP8755_BUCK0, LP8755_BUCK3, LP8755_BUCK4, LP8755_BUCK5} },
267 	{ 3, { LP8755_BUCK0, LP8755_BUCK4, LP8755_BUCK5} },
268 	{ 2, { LP8755_BUCK0, LP8755_BUCK5} },
269 	{ 1, { LP8755_BUCK0} },
270 	{ 2, { LP8755_BUCK0, LP8755_BUCK3} },
271 	{ 4, { LP8755_BUCK0, LP8755_BUCK2, LP8755_BUCK3, LP8755_BUCK5} },
272 };
273 
274 static int lp8755_init_data(struct lp8755_chip *pchip)
275 {
276 	unsigned int regval;
277 	int ret, icnt, buck_num;
278 	struct lp8755_platform_data *pdata = pchip->pdata;
279 
280 	/* read back  muti-phase configuration */
281 	ret = lp8755_read(pchip, 0x3D, &regval);
282 	if (ret < 0)
283 		goto out_i2c_error;
284 	pchip->mphase = regval & 0x0F;
285 
286 	/* set default data based on multi-phase config */
287 	for (icnt = 0; icnt < mphase_buck[pchip->mphase].nreg; icnt++) {
288 		buck_num = mphase_buck[pchip->mphase].buck_num[icnt];
289 		pdata->buck_data[buck_num] = &lp8755_reg_default[buck_num];
290 	}
291 	return ret;
292 
293 out_i2c_error:
294 	dev_err(pchip->dev, "i2c access error %s\n", __func__);
295 	return ret;
296 }
297 
298 #define lp8755_buck_desc(_id)\
299 {\
300 	.name = lp8755_rail(_id),\
301 	.id   = LP8755_BUCK##_id,\
302 	.ops  = &lp8755_buck_ops,\
303 	.n_voltages = LP8755_BUCK_LINEAR_OUT_MAX+1,\
304 	.uV_step = 10000,\
305 	.min_uV = 500000,\
306 	.type = REGULATOR_VOLTAGE,\
307 	.owner = THIS_MODULE,\
308 	.enable_reg = LP8755_REG_BUCK##_id,\
309 	.enable_mask = LP8755_BUCK_EN_M,\
310 	.vsel_reg = LP8755_REG_BUCK##_id,\
311 	.vsel_mask = LP8755_BUCK_VOUT_M,\
312 }
313 
314 static const struct regulator_desc lp8755_regulators[] = {
315 	lp8755_buck_desc(0),
316 	lp8755_buck_desc(1),
317 	lp8755_buck_desc(2),
318 	lp8755_buck_desc(3),
319 	lp8755_buck_desc(4),
320 	lp8755_buck_desc(5),
321 };
322 
323 static int lp8755_regulator_init(struct lp8755_chip *pchip)
324 {
325 	int ret, icnt, buck_num;
326 	struct lp8755_platform_data *pdata = pchip->pdata;
327 	struct regulator_config rconfig = { };
328 
329 	rconfig.regmap = pchip->regmap;
330 	rconfig.dev = pchip->dev;
331 	rconfig.driver_data = pchip;
332 
333 	for (icnt = 0; icnt < mphase_buck[pchip->mphase].nreg; icnt++) {
334 		buck_num = mphase_buck[pchip->mphase].buck_num[icnt];
335 		rconfig.init_data = pdata->buck_data[buck_num];
336 		rconfig.of_node = pchip->dev->of_node;
337 		pchip->rdev[buck_num] =
338 		    devm_regulator_register(pchip->dev,
339 				    &lp8755_regulators[buck_num], &rconfig);
340 		if (IS_ERR(pchip->rdev[buck_num])) {
341 			ret = PTR_ERR(pchip->rdev[buck_num]);
342 			pchip->rdev[buck_num] = NULL;
343 			dev_err(pchip->dev, "regulator init failed: buck %d\n",
344 				buck_num);
345 			return ret;
346 		}
347 	}
348 
349 	return 0;
350 }
351 
352 static irqreturn_t lp8755_irq_handler(int irq, void *data)
353 {
354 	int ret, icnt;
355 	unsigned int flag0, flag1;
356 	struct lp8755_chip *pchip = data;
357 
358 	/* read flag0 register */
359 	ret = lp8755_read(pchip, 0x0D, &flag0);
360 	if (ret < 0)
361 		goto err_i2c;
362 	/* clear flag register to pull up int. pin */
363 	ret = lp8755_write(pchip, 0x0D, 0x00);
364 	if (ret < 0)
365 		goto err_i2c;
366 
367 	/* sent power fault detection event to specific regulator */
368 	for (icnt = 0; icnt < LP8755_BUCK_MAX; icnt++)
369 		if ((flag0 & (0x4 << icnt))
370 		    && (pchip->irqmask & (0x04 << icnt))
371 		    && (pchip->rdev[icnt] != NULL)) {
372 			regulator_lock(pchip->rdev[icnt]);
373 			regulator_notifier_call_chain(pchip->rdev[icnt],
374 						      LP8755_EVENT_PWR_FAULT,
375 						      NULL);
376 			regulator_unlock(pchip->rdev[icnt]);
377 		}
378 
379 	/* read flag1 register */
380 	ret = lp8755_read(pchip, 0x0E, &flag1);
381 	if (ret < 0)
382 		goto err_i2c;
383 	/* clear flag register to pull up int. pin */
384 	ret = lp8755_write(pchip, 0x0E, 0x00);
385 	if (ret < 0)
386 		goto err_i2c;
387 
388 	/* send OCP event to all regulator devices */
389 	if ((flag1 & 0x01) && (pchip->irqmask & 0x01))
390 		for (icnt = 0; icnt < LP8755_BUCK_MAX; icnt++)
391 			if (pchip->rdev[icnt] != NULL) {
392 				regulator_lock(pchip->rdev[icnt]);
393 				regulator_notifier_call_chain(pchip->rdev[icnt],
394 							      LP8755_EVENT_OCP,
395 							      NULL);
396 				regulator_unlock(pchip->rdev[icnt]);
397 			}
398 
399 	/* send OVP event to all regulator devices */
400 	if ((flag1 & 0x02) && (pchip->irqmask & 0x02))
401 		for (icnt = 0; icnt < LP8755_BUCK_MAX; icnt++)
402 			if (pchip->rdev[icnt] != NULL) {
403 				regulator_lock(pchip->rdev[icnt]);
404 				regulator_notifier_call_chain(pchip->rdev[icnt],
405 							      LP8755_EVENT_OVP,
406 							      NULL);
407 				regulator_unlock(pchip->rdev[icnt]);
408 			}
409 	return IRQ_HANDLED;
410 
411 err_i2c:
412 	dev_err(pchip->dev, "i2c access error %s\n", __func__);
413 	return IRQ_NONE;
414 }
415 
416 static int lp8755_int_config(struct lp8755_chip *pchip)
417 {
418 	int ret;
419 	unsigned int regval;
420 
421 	if (pchip->irq == 0) {
422 		dev_warn(pchip->dev, "not use interrupt : %s\n", __func__);
423 		return 0;
424 	}
425 
426 	ret = lp8755_read(pchip, 0x0F, &regval);
427 	if (ret < 0) {
428 		dev_err(pchip->dev, "i2c access error %s\n", __func__);
429 		return ret;
430 	}
431 
432 	pchip->irqmask = regval;
433 	return devm_request_threaded_irq(pchip->dev, pchip->irq, NULL,
434 					 lp8755_irq_handler,
435 					 IRQF_TRIGGER_FALLING | IRQF_ONESHOT,
436 					 "lp8755-irq", pchip);
437 }
438 
439 static const struct regmap_config lp8755_regmap = {
440 	.reg_bits = 8,
441 	.val_bits = 8,
442 	.max_register = LP8755_REG_MAX,
443 };
444 
445 static int lp8755_probe(struct i2c_client *client,
446 			const struct i2c_device_id *id)
447 {
448 	int ret, icnt;
449 	struct lp8755_chip *pchip;
450 	struct lp8755_platform_data *pdata = dev_get_platdata(&client->dev);
451 
452 	if (!i2c_check_functionality(client->adapter, I2C_FUNC_I2C)) {
453 		dev_err(&client->dev, "i2c functionality check fail.\n");
454 		return -EOPNOTSUPP;
455 	}
456 
457 	pchip = devm_kzalloc(&client->dev,
458 			     sizeof(struct lp8755_chip), GFP_KERNEL);
459 	if (!pchip)
460 		return -ENOMEM;
461 
462 	pchip->dev = &client->dev;
463 	pchip->regmap = devm_regmap_init_i2c(client, &lp8755_regmap);
464 	if (IS_ERR(pchip->regmap)) {
465 		ret = PTR_ERR(pchip->regmap);
466 		dev_err(&client->dev, "fail to allocate regmap %d\n", ret);
467 		return ret;
468 	}
469 	i2c_set_clientdata(client, pchip);
470 
471 	if (pdata != NULL) {
472 		pchip->pdata = pdata;
473 		pchip->mphase = pdata->mphase;
474 	} else {
475 		pchip->pdata = devm_kzalloc(pchip->dev,
476 					    sizeof(struct lp8755_platform_data),
477 					    GFP_KERNEL);
478 		if (!pchip->pdata)
479 			return -ENOMEM;
480 		ret = lp8755_init_data(pchip);
481 		if (ret < 0) {
482 			dev_err(&client->dev, "fail to initialize chip\n");
483 			return ret;
484 		}
485 	}
486 
487 	ret = lp8755_regulator_init(pchip);
488 	if (ret < 0) {
489 		dev_err(&client->dev, "fail to initialize regulators\n");
490 		goto err;
491 	}
492 
493 	pchip->irq = client->irq;
494 	ret = lp8755_int_config(pchip);
495 	if (ret < 0) {
496 		dev_err(&client->dev, "fail to irq config\n");
497 		goto err;
498 	}
499 
500 	return ret;
501 
502 err:
503 	/* output disable */
504 	for (icnt = 0; icnt < LP8755_BUCK_MAX; icnt++)
505 		lp8755_write(pchip, icnt, 0x00);
506 
507 	return ret;
508 }
509 
510 static int lp8755_remove(struct i2c_client *client)
511 {
512 	int icnt;
513 	struct lp8755_chip *pchip = i2c_get_clientdata(client);
514 
515 	for (icnt = 0; icnt < LP8755_BUCK_MAX; icnt++)
516 		lp8755_write(pchip, icnt, 0x00);
517 
518 	return 0;
519 }
520 
521 static const struct i2c_device_id lp8755_id[] = {
522 	{LP8755_NAME, 0},
523 	{}
524 };
525 
526 MODULE_DEVICE_TABLE(i2c, lp8755_id);
527 
528 static struct i2c_driver lp8755_i2c_driver = {
529 	.driver = {
530 		   .name = LP8755_NAME,
531 		   },
532 	.probe = lp8755_probe,
533 	.remove = lp8755_remove,
534 	.id_table = lp8755_id,
535 };
536 
537 static int __init lp8755_init(void)
538 {
539 	return i2c_add_driver(&lp8755_i2c_driver);
540 }
541 
542 subsys_initcall(lp8755_init);
543 
544 static void __exit lp8755_exit(void)
545 {
546 	i2c_del_driver(&lp8755_i2c_driver);
547 }
548 
549 module_exit(lp8755_exit);
550 
551 MODULE_DESCRIPTION("Texas Instruments lp8755 driver");
552 MODULE_AUTHOR("Daniel Jeong <daniel.jeong@ti.com>");
553 MODULE_LICENSE("GPL v2");
554