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/uaccess.h>
23#include <linux/regulator/driver.h>
24#include <linux/regulator/machine.h>
25#include <linux/platform_data/lp8755.h>
26
27#define LP8755_REG_BUCK0 0x00
28#define LP8755_REG_BUCK1 0x03
29#define LP8755_REG_BUCK2 0x04
30#define LP8755_REG_BUCK3 0x01
31#define LP8755_REG_BUCK4 0x05
32#define LP8755_REG_BUCK5 0x02
33#define LP8755_REG_MAX 0xFF
34
35#define LP8755_BUCK_EN_M BIT(7)
36#define LP8755_BUCK_LINEAR_OUT_MAX 0x76
37#define LP8755_BUCK_VOUT_M 0x7F
38
39struct lp8755_mphase {
40 int nreg;
41 int buck_num[LP8755_BUCK_MAX];
42};
43
44struct lp8755_chip {
45 struct device *dev;
46 struct regmap *regmap;
47 struct lp8755_platform_data *pdata;
48
49 int irq;
50 unsigned int irqmask;
51
52 int mphase;
53 struct regulator_dev *rdev[LP8755_BUCK_MAX];
54};
55
56/**
57 *lp8755_read : read a single register value from lp8755.
58 *@pchip : device to read from
59 *@reg : register to read from
60 *@val : pointer to store read value
61 */
62static int lp8755_read(struct lp8755_chip *pchip, unsigned int reg,
63 unsigned int *val)
64{
65 return regmap_read(pchip->regmap, reg, val);
66}
67
68/**
69 *lp8755_write : write a single register value to lp8755.
70 *@pchip : device to write to
71 *@reg : register to write to
72 *@val : value to be written
73 */
74static int lp8755_write(struct lp8755_chip *pchip, unsigned int reg,
75 unsigned int val)
76{
77 return regmap_write(pchip->regmap, reg, val);
78}
79
80/**
81 *lp8755_update_bits : set the values of bit fields in lp8755 register.
82 *@pchip : device to read from
83 *@reg : register to update
84 *@mask : bitmask to be changed
85 *@val : value for bitmask
86 */
87static int lp8755_update_bits(struct lp8755_chip *pchip, unsigned int reg,
88 unsigned int mask, unsigned int val)
89{
90 return regmap_update_bits(pchip->regmap, reg, mask, val);
91}
92
93static int lp8755_buck_enable_time(struct regulator_dev *rdev)
94{
95 int ret;
96 unsigned int regval;
97 enum lp8755_bucks id = rdev_get_id(rdev);
98 struct lp8755_chip *pchip = rdev_get_drvdata(rdev);
99
100 ret = lp8755_read(pchip, 0x12 + id, &regval);
101 if (ret < 0) {
102 dev_err(pchip->dev, "i2c access error %s\n", __func__);
103 return ret;
104 }
105 return (regval & 0xff) * 100;
106}
107
108static int lp8755_buck_set_mode(struct regulator_dev *rdev, unsigned int mode)
109{
110 int ret;
111 unsigned int regbval = 0x0;
112 enum lp8755_bucks id = rdev_get_id(rdev);
113 struct lp8755_chip *pchip = rdev_get_drvdata(rdev);
114
115 switch (mode) {
116 case REGULATOR_MODE_FAST:
117 /* forced pwm mode */
118 regbval = (0x01 << id);
119 break;
120 case REGULATOR_MODE_NORMAL:
121 /* enable automatic pwm/pfm mode */
122 ret = lp8755_update_bits(pchip, 0x08 + id, 0x20, 0x00);
123 if (ret < 0)
124 goto err_i2c;
125 break;
126 case REGULATOR_MODE_IDLE:
127 /* enable automatic pwm/pfm/lppfm mode */
128 ret = lp8755_update_bits(pchip, 0x08 + id, 0x20, 0x20);
129 if (ret < 0)
130 goto err_i2c;
131
132 ret = lp8755_update_bits(pchip, 0x10, 0x01, 0x01);
133 if (ret < 0)
134 goto err_i2c;
135 break;
136 default:
137 dev_err(pchip->dev, "Not supported buck mode %s\n", __func__);
138 /* forced pwm mode */
139 regbval = (0x01 << id);
140 }
141
142 ret = lp8755_update_bits(pchip, 0x06, 0x01 << id, regbval);
143 if (ret < 0)
144 goto err_i2c;
145 return ret;
146err_i2c:
147 dev_err(pchip->dev, "i2c access error %s\n", __func__);
148 return ret;
149}
150
151static unsigned int lp8755_buck_get_mode(struct regulator_dev *rdev)
152{
153 int ret;
154 unsigned int regval;
155 enum lp8755_bucks id = rdev_get_id(rdev);
156 struct lp8755_chip *pchip = rdev_get_drvdata(rdev);
157
158 ret = lp8755_read(pchip, 0x06, &regval);
159 if (ret < 0)
160 goto err_i2c;
161
162 /* mode fast means forced pwm mode */
163 if (regval & (0x01 << id))
164 return REGULATOR_MODE_FAST;
165
166 ret = lp8755_read(pchip, 0x08 + id, &regval);
167 if (ret < 0)
168 goto err_i2c;
169
170 /* mode idle means automatic pwm/pfm/lppfm mode */
171 if (regval & 0x20)
172 return REGULATOR_MODE_IDLE;
173
174 /* mode normal means automatic pwm/pfm mode */
175 return REGULATOR_MODE_NORMAL;
176
177err_i2c:
178 dev_err(pchip->dev, "i2c access error %s\n", __func__);
179 return 0;
180}
181
182static int lp8755_buck_set_ramp(struct regulator_dev *rdev, int ramp)
183{
184 int ret;
185 unsigned int regval = 0x00;
186 enum lp8755_bucks id = rdev_get_id(rdev);
187 struct lp8755_chip *pchip = rdev_get_drvdata(rdev);
188
189 /* uV/us */
190 switch (ramp) {
191 case 0 ... 230:
192 regval = 0x07;
193 break;
194 case 231 ... 470:
195 regval = 0x06;
196 break;
197 case 471 ... 940:
198 regval = 0x05;
199 break;
200 case 941 ... 1900:
201 regval = 0x04;
202 break;
203 case 1901 ... 3800:
204 regval = 0x03;
205 break;
206 case 3801 ... 7500:
207 regval = 0x02;
208 break;
209 case 7501 ... 15000:
210 regval = 0x01;
211 break;
212 case 15001 ... 30000:
213 regval = 0x00;
214 break;
215 default:
216 dev_err(pchip->dev,
217 "Not supported ramp value %d %s\n", ramp, __func__);
218 return -EINVAL;
219 }
220
221 ret = lp8755_update_bits(pchip, 0x07 + id, 0x07, regval);
222 if (ret < 0)
223 goto err_i2c;
224 return ret;
225err_i2c:
226 dev_err(pchip->dev, "i2c access error %s\n", __func__);
227 return ret;
228}
229
230static const struct regulator_ops lp8755_buck_ops = {
231 .map_voltage = regulator_map_voltage_linear,
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
255static 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
264static 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
278static 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
297out_i2c_error:
298 dev_err(pchip->dev, "i2c access 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
318static const 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
327static 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 devm_regulator_register(pchip->dev,
343 &lp8755_regulators[buck_num], &rconfig);
344 if (IS_ERR(pchip->rdev[buck_num])) {
345 ret = PTR_ERR(pchip->rdev[buck_num]);
346 pchip->rdev[buck_num] = NULL;
347 dev_err(pchip->dev, "regulator init failed: buck %d\n",
348 buck_num);
349 return ret;
350 }
351 }
352
353 return 0;
354}
355
356static irqreturn_t lp8755_irq_handler(int irq, void *data)
357{
358 int ret, icnt;
359 unsigned int flag0, flag1;
360 struct lp8755_chip *pchip = data;
361
362 /* read flag0 register */
363 ret = lp8755_read(pchip, 0x0D, &flag0);
364 if (ret < 0)
365 goto err_i2c;
366 /* clear flag register to pull up int. pin */
367 ret = lp8755_write(pchip, 0x0D, 0x00);
368 if (ret < 0)
369 goto err_i2c;
370
371 /* sent power fault detection event to specific regulator */
372 for (icnt = 0; icnt < LP8755_BUCK_MAX; icnt++)
373 if ((flag0 & (0x4 << icnt))
374 && (pchip->irqmask & (0x04 << icnt))
375 && (pchip->rdev[icnt] != NULL))
376 regulator_notifier_call_chain(pchip->rdev[icnt],
377 LP8755_EVENT_PWR_FAULT,
378 NULL);
379
380 /* read flag1 register */
381 ret = lp8755_read(pchip, 0x0E, &flag1);
382 if (ret < 0)
383 goto err_i2c;
384 /* clear flag register to pull up int. pin */
385 ret = lp8755_write(pchip, 0x0E, 0x00);
386 if (ret < 0)
387 goto err_i2c;
388
389 /* send OCP event to all regulator devices */
390 if ((flag1 & 0x01) && (pchip->irqmask & 0x01))
391 for (icnt = 0; icnt < LP8755_BUCK_MAX; icnt++)
392 if (pchip->rdev[icnt] != NULL)
393 regulator_notifier_call_chain(pchip->rdev[icnt],
394 LP8755_EVENT_OCP,
395 NULL);
396
397 /* send OVP event to all regulator devices */
398 if ((flag1 & 0x02) && (pchip->irqmask & 0x02))
399 for (icnt = 0; icnt < LP8755_BUCK_MAX; icnt++)
400 if (pchip->rdev[icnt] != NULL)
401 regulator_notifier_call_chain(pchip->rdev[icnt],
402 LP8755_EVENT_OVP,
403 NULL);
404 return IRQ_HANDLED;
405
406err_i2c:
407 dev_err(pchip->dev, "i2c access error %s\n", __func__);
408 return IRQ_NONE;
409}
410
411static int lp8755_int_config(struct lp8755_chip *pchip)
412{
413 int ret;
414 unsigned int regval;
415
416 if (pchip->irq == 0) {
417 dev_warn(pchip->dev, "not use interrupt : %s\n", __func__);
418 return 0;
419 }
420
421 ret = lp8755_read(pchip, 0x0F, &regval);
422 if (ret < 0) {
423 dev_err(pchip->dev, "i2c access error %s\n", __func__);
424 return ret;
425 }
426
427 pchip->irqmask = regval;
428 return devm_request_threaded_irq(pchip->dev, pchip->irq, NULL,
429 lp8755_irq_handler,
430 IRQF_TRIGGER_FALLING | IRQF_ONESHOT,
431 "lp8755-irq", pchip);
432}
433
434static const struct regmap_config lp8755_regmap = {
435 .reg_bits = 8,
436 .val_bits = 8,
437 .max_register = LP8755_REG_MAX,
438};
439
440static int lp8755_probe(struct i2c_client *client,
441 const struct i2c_device_id *id)
442{
443 int ret, icnt;
444 struct lp8755_chip *pchip;
445 struct lp8755_platform_data *pdata = dev_get_platdata(&client->dev);
446
447 if (!i2c_check_functionality(client->adapter, I2C_FUNC_I2C)) {
448 dev_err(&client->dev, "i2c functionality check fail.\n");
449 return -EOPNOTSUPP;
450 }
451
452 pchip = devm_kzalloc(&client->dev,
453 sizeof(struct lp8755_chip), GFP_KERNEL);
454 if (!pchip)
455 return -ENOMEM;
456
457 pchip->dev = &client->dev;
458 pchip->regmap = devm_regmap_init_i2c(client, &lp8755_regmap);
459 if (IS_ERR(pchip->regmap)) {
460 ret = PTR_ERR(pchip->regmap);
461 dev_err(&client->dev, "fail to allocate regmap %d\n", ret);
462 return ret;
463 }
464 i2c_set_clientdata(client, pchip);
465
466 if (pdata != NULL) {
467 pchip->pdata = pdata;
468 pchip->mphase = pdata->mphase;
469 } else {
470 pchip->pdata = devm_kzalloc(pchip->dev,
471 sizeof(struct lp8755_platform_data),
472 GFP_KERNEL);
473 if (!pchip->pdata)
474 return -ENOMEM;
475 ret = lp8755_init_data(pchip);
476 if (ret < 0) {
477 dev_err(&client->dev, "fail to initialize chip\n");
478 return ret;
479 }
480 }
481
482 ret = lp8755_regulator_init(pchip);
483 if (ret < 0) {
484 dev_err(&client->dev, "fail to initialize regulators\n");
485 goto err;
486 }
487
488 pchip->irq = client->irq;
489 ret = lp8755_int_config(pchip);
490 if (ret < 0) {
491 dev_err(&client->dev, "fail to irq config\n");
492 goto err;
493 }
494
495 return ret;
496
497err:
498 /* output disable */
499 for (icnt = 0; icnt < LP8755_BUCK_MAX; icnt++)
500 lp8755_write(pchip, icnt, 0x00);
501
502 return ret;
503}
504
505static int lp8755_remove(struct i2c_client *client)
506{
507 int icnt;
508 struct lp8755_chip *pchip = i2c_get_clientdata(client);
509
510 for (icnt = 0; icnt < LP8755_BUCK_MAX; icnt++)
511 lp8755_write(pchip, icnt, 0x00);
512
513 return 0;
514}
515
516static const struct i2c_device_id lp8755_id[] = {
517 {LP8755_NAME, 0},
518 {}
519};
520
521MODULE_DEVICE_TABLE(i2c, lp8755_id);
522
523static struct i2c_driver lp8755_i2c_driver = {
524 .driver = {
525 .name = LP8755_NAME,
526 },
527 .probe = lp8755_probe,
528 .remove = lp8755_remove,
529 .id_table = lp8755_id,
530};
531
532static int __init lp8755_init(void)
533{
534 return i2c_add_driver(&lp8755_i2c_driver);
535}
536
537subsys_initcall(lp8755_init);
538
539static void __exit lp8755_exit(void)
540{
541 i2c_del_driver(&lp8755_i2c_driver);
542}
543
544module_exit(lp8755_exit);
545
546MODULE_DESCRIPTION("Texas Instruments lp8755 driver");
547MODULE_AUTHOR("Daniel Jeong <daniel.jeong@ti.com>");
548MODULE_LICENSE("GPL v2");
549