1/*
2 * max8998.c - Voltage regulator driver for the Maxim 8998
3 *
4 *  Copyright (C) 2009-2010 Samsung Electronics
5 *  Kyungmin Park <kyungmin.park@samsung.com>
6 *  Marek Szyprowski <m.szyprowski@samsung.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 as published by
10 * the Free Software Foundation; either version 2 of the License, or
11 * (at your option) any later version.
12 *
13 * This program is distributed in the hope that it will be useful,
14 * but WITHOUT ANY WARRANTY; without even the implied warranty of
15 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
16 * GNU General Public License for more details.
17 *
18 * You should have received a copy of the GNU General Public License
19 * along with this program; if not, write to the Free Software
20 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
21 */
22
23#include <linux/module.h>
24#include <linux/init.h>
25#include <linux/i2c.h>
26#include <linux/err.h>
27#include <linux/gpio.h>
28#include <linux/slab.h>
29#include <linux/interrupt.h>
30#include <linux/mutex.h>
31#include <linux/of.h>
32#include <linux/of_gpio.h>
33#include <linux/platform_device.h>
34#include <linux/regulator/driver.h>
35#include <linux/regulator/of_regulator.h>
36#include <linux/mfd/max8998.h>
37#include <linux/mfd/max8998-private.h>
38
39struct max8998_data {
40	struct device		*dev;
41	struct max8998_dev	*iodev;
42	int			num_regulators;
43	u8                      buck1_vol[4]; /* voltages for selection */
44	u8                      buck2_vol[2];
45	unsigned int		buck1_idx; /* index to last changed voltage */
46					   /* value in a set */
47	unsigned int		buck2_idx;
48};
49
50struct voltage_map_desc {
51	int min;
52	int max;
53	int step;
54};
55
56/* Voltage maps in uV*/
57static const struct voltage_map_desc ldo23_voltage_map_desc = {
58	.min = 800000,	.step = 50000,	.max = 1300000,
59};
60static const struct voltage_map_desc ldo456711_voltage_map_desc = {
61	.min = 1600000,	.step = 100000,	.max = 3600000,
62};
63static const struct voltage_map_desc ldo8_voltage_map_desc = {
64	.min = 3000000,	.step = 100000,	.max = 3600000,
65};
66static const struct voltage_map_desc ldo9_voltage_map_desc = {
67	.min = 2800000,	.step = 100000,	.max = 3100000,
68};
69static const struct voltage_map_desc ldo10_voltage_map_desc = {
70	.min = 950000,	.step = 50000,	.max = 1300000,
71};
72static const struct voltage_map_desc ldo1213_voltage_map_desc = {
73	.min = 800000,	.step = 100000,	.max = 3300000,
74};
75static const struct voltage_map_desc ldo1415_voltage_map_desc = {
76	.min = 1200000,	.step = 100000,	.max = 3300000,
77};
78static const struct voltage_map_desc ldo1617_voltage_map_desc = {
79	.min = 1600000,	.step = 100000,	.max = 3600000,
80};
81static const struct voltage_map_desc buck12_voltage_map_desc = {
82	.min = 750000,	.step = 25000,	.max = 1525000,
83};
84static const struct voltage_map_desc buck3_voltage_map_desc = {
85	.min = 1600000,	.step = 100000,	.max = 3600000,
86};
87static const struct voltage_map_desc buck4_voltage_map_desc = {
88	.min = 800000,	.step = 100000,	.max = 2300000,
89};
90
91static const struct voltage_map_desc *ldo_voltage_map[] = {
92	NULL,
93	NULL,
94	&ldo23_voltage_map_desc,	/* LDO2 */
95	&ldo23_voltage_map_desc,	/* LDO3 */
96	&ldo456711_voltage_map_desc,	/* LDO4 */
97	&ldo456711_voltage_map_desc,	/* LDO5 */
98	&ldo456711_voltage_map_desc,	/* LDO6 */
99	&ldo456711_voltage_map_desc,	/* LDO7 */
100	&ldo8_voltage_map_desc,		/* LDO8 */
101	&ldo9_voltage_map_desc,		/* LDO9 */
102	&ldo10_voltage_map_desc,	/* LDO10 */
103	&ldo456711_voltage_map_desc,	/* LDO11 */
104	&ldo1213_voltage_map_desc,	/* LDO12 */
105	&ldo1213_voltage_map_desc,	/* LDO13 */
106	&ldo1415_voltage_map_desc,	/* LDO14 */
107	&ldo1415_voltage_map_desc,	/* LDO15 */
108	&ldo1617_voltage_map_desc,	/* LDO16 */
109	&ldo1617_voltage_map_desc,	/* LDO17 */
110	&buck12_voltage_map_desc,	/* BUCK1 */
111	&buck12_voltage_map_desc,	/* BUCK2 */
112	&buck3_voltage_map_desc,	/* BUCK3 */
113	&buck4_voltage_map_desc,	/* BUCK4 */
114};
115
116static int max8998_get_enable_register(struct regulator_dev *rdev,
117					int *reg, int *shift)
118{
119	int ldo = rdev_get_id(rdev);
120
121	switch (ldo) {
122	case MAX8998_LDO2 ... MAX8998_LDO5:
123		*reg = MAX8998_REG_ONOFF1;
124		*shift = 3 - (ldo - MAX8998_LDO2);
125		break;
126	case MAX8998_LDO6 ... MAX8998_LDO13:
127		*reg = MAX8998_REG_ONOFF2;
128		*shift = 7 - (ldo - MAX8998_LDO6);
129		break;
130	case MAX8998_LDO14 ... MAX8998_LDO17:
131		*reg = MAX8998_REG_ONOFF3;
132		*shift = 7 - (ldo - MAX8998_LDO14);
133		break;
134	case MAX8998_BUCK1 ... MAX8998_BUCK4:
135		*reg = MAX8998_REG_ONOFF1;
136		*shift = 7 - (ldo - MAX8998_BUCK1);
137		break;
138	case MAX8998_EN32KHZ_AP ... MAX8998_ENVICHG:
139		*reg = MAX8998_REG_ONOFF4;
140		*shift = 7 - (ldo - MAX8998_EN32KHZ_AP);
141		break;
142	case MAX8998_ESAFEOUT1 ... MAX8998_ESAFEOUT2:
143		*reg = MAX8998_REG_CHGR2;
144		*shift = 7 - (ldo - MAX8998_ESAFEOUT1);
145		break;
146	default:
147		return -EINVAL;
148	}
149
150	return 0;
151}
152
153static int max8998_ldo_is_enabled(struct regulator_dev *rdev)
154{
155	struct max8998_data *max8998 = rdev_get_drvdata(rdev);
156	struct i2c_client *i2c = max8998->iodev->i2c;
157	int ret, reg, shift = 8;
158	u8 val;
159
160	ret = max8998_get_enable_register(rdev, &reg, &shift);
161	if (ret)
162		return ret;
163
164	ret = max8998_read_reg(i2c, reg, &val);
165	if (ret)
166		return ret;
167
168	return val & (1 << shift);
169}
170
171static int max8998_ldo_enable(struct regulator_dev *rdev)
172{
173	struct max8998_data *max8998 = rdev_get_drvdata(rdev);
174	struct i2c_client *i2c = max8998->iodev->i2c;
175	int reg, shift = 8, ret;
176
177	ret = max8998_get_enable_register(rdev, &reg, &shift);
178	if (ret)
179		return ret;
180
181	return max8998_update_reg(i2c, reg, 1<<shift, 1<<shift);
182}
183
184static int max8998_ldo_disable(struct regulator_dev *rdev)
185{
186	struct max8998_data *max8998 = rdev_get_drvdata(rdev);
187	struct i2c_client *i2c = max8998->iodev->i2c;
188	int reg, shift = 8, ret;
189
190	ret = max8998_get_enable_register(rdev, &reg, &shift);
191	if (ret)
192		return ret;
193
194	return max8998_update_reg(i2c, reg, 0, 1<<shift);
195}
196
197static int max8998_get_voltage_register(struct regulator_dev *rdev,
198				int *_reg, int *_shift, int *_mask)
199{
200	int ldo = rdev_get_id(rdev);
201	struct max8998_data *max8998 = rdev_get_drvdata(rdev);
202	int reg, shift = 0, mask = 0xff;
203
204	switch (ldo) {
205	case MAX8998_LDO2 ... MAX8998_LDO3:
206		reg = MAX8998_REG_LDO2_LDO3;
207		mask = 0xf;
208		if (ldo == MAX8998_LDO2)
209			shift = 4;
210		else
211			shift = 0;
212		break;
213	case MAX8998_LDO4 ... MAX8998_LDO7:
214		reg = MAX8998_REG_LDO4 + (ldo - MAX8998_LDO4);
215		break;
216	case MAX8998_LDO8 ... MAX8998_LDO9:
217		reg = MAX8998_REG_LDO8_LDO9;
218		mask = 0xf;
219		if (ldo == MAX8998_LDO8)
220			shift = 4;
221		else
222			shift = 0;
223		break;
224	case MAX8998_LDO10 ... MAX8998_LDO11:
225		reg = MAX8998_REG_LDO10_LDO11;
226		if (ldo == MAX8998_LDO10) {
227			shift = 5;
228			mask = 0x7;
229		} else {
230			shift = 0;
231			mask = 0x1f;
232		}
233		break;
234	case MAX8998_LDO12 ... MAX8998_LDO17:
235		reg = MAX8998_REG_LDO12 + (ldo - MAX8998_LDO12);
236		break;
237	case MAX8998_BUCK1:
238		reg = MAX8998_REG_BUCK1_VOLTAGE1 + max8998->buck1_idx;
239		break;
240	case MAX8998_BUCK2:
241		reg = MAX8998_REG_BUCK2_VOLTAGE1 + max8998->buck2_idx;
242		break;
243	case MAX8998_BUCK3:
244		reg = MAX8998_REG_BUCK3;
245		break;
246	case MAX8998_BUCK4:
247		reg = MAX8998_REG_BUCK4;
248		break;
249	default:
250		return -EINVAL;
251	}
252
253	*_reg = reg;
254	*_shift = shift;
255	*_mask = mask;
256
257	return 0;
258}
259
260static int max8998_get_voltage_sel(struct regulator_dev *rdev)
261{
262	struct max8998_data *max8998 = rdev_get_drvdata(rdev);
263	struct i2c_client *i2c = max8998->iodev->i2c;
264	int reg, shift = 0, mask, ret;
265	u8 val;
266
267	ret = max8998_get_voltage_register(rdev, &reg, &shift, &mask);
268	if (ret)
269		return ret;
270
271	ret = max8998_read_reg(i2c, reg, &val);
272	if (ret)
273		return ret;
274
275	val >>= shift;
276	val &= mask;
277
278	return val;
279}
280
281static int max8998_set_voltage_ldo_sel(struct regulator_dev *rdev,
282				       unsigned selector)
283{
284	struct max8998_data *max8998 = rdev_get_drvdata(rdev);
285	struct i2c_client *i2c = max8998->iodev->i2c;
286	int reg, shift = 0, mask, ret;
287
288	ret = max8998_get_voltage_register(rdev, &reg, &shift, &mask);
289	if (ret)
290		return ret;
291
292	ret = max8998_update_reg(i2c, reg, selector<<shift, mask<<shift);
293
294	return ret;
295}
296
297static inline void buck1_gpio_set(int gpio1, int gpio2, int v)
298{
299	gpio_set_value(gpio1, v & 0x1);
300	gpio_set_value(gpio2, (v >> 1) & 0x1);
301}
302
303static inline void buck2_gpio_set(int gpio, int v)
304{
305	gpio_set_value(gpio, v & 0x1);
306}
307
308static int max8998_set_voltage_buck_sel(struct regulator_dev *rdev,
309					unsigned selector)
310{
311	struct max8998_data *max8998 = rdev_get_drvdata(rdev);
312	struct max8998_platform_data *pdata =
313		dev_get_platdata(max8998->iodev->dev);
314	struct i2c_client *i2c = max8998->iodev->i2c;
315	int buck = rdev_get_id(rdev);
316	int reg, shift = 0, mask, ret, j;
317	static u8 buck1_last_val;
318
319	ret = max8998_get_voltage_register(rdev, &reg, &shift, &mask);
320	if (ret)
321		return ret;
322
323	switch (buck) {
324	case MAX8998_BUCK1:
325		dev_dbg(max8998->dev,
326			"BUCK1, selector:%d, buck1_vol1:%d, buck1_vol2:%d\n"
327			"buck1_vol3:%d, buck1_vol4:%d\n",
328			selector, max8998->buck1_vol[0], max8998->buck1_vol[1],
329			max8998->buck1_vol[2], max8998->buck1_vol[3]);
330
331		if (gpio_is_valid(pdata->buck1_set1) &&
332		    gpio_is_valid(pdata->buck1_set2)) {
333
334			/* check if requested voltage */
335			/* value is already defined */
336			for (j = 0; j < ARRAY_SIZE(max8998->buck1_vol); j++) {
337				if (max8998->buck1_vol[j] == selector) {
338					max8998->buck1_idx = j;
339					buck1_gpio_set(pdata->buck1_set1,
340						       pdata->buck1_set2, j);
341					goto buck1_exit;
342				}
343			}
344
345			if (pdata->buck_voltage_lock)
346				return -EINVAL;
347
348			/* no predefine regulator found */
349			max8998->buck1_idx = (buck1_last_val % 2) + 2;
350			dev_dbg(max8998->dev, "max8998->buck1_idx:%d\n",
351				max8998->buck1_idx);
352			max8998->buck1_vol[max8998->buck1_idx] = selector;
353			ret = max8998_get_voltage_register(rdev, &reg,
354							   &shift,
355							   &mask);
356			ret = max8998_write_reg(i2c, reg, selector);
357			buck1_gpio_set(pdata->buck1_set1,
358				       pdata->buck1_set2, max8998->buck1_idx);
359			buck1_last_val++;
360buck1_exit:
361			dev_dbg(max8998->dev, "%s: SET1:%d, SET2:%d\n",
362				i2c->name, gpio_get_value(pdata->buck1_set1),
363				gpio_get_value(pdata->buck1_set2));
364			break;
365		} else {
366			ret = max8998_write_reg(i2c, reg, selector);
367		}
368		break;
369
370	case MAX8998_BUCK2:
371		dev_dbg(max8998->dev,
372			"BUCK2, selector:%d buck2_vol1:%d, buck2_vol2:%d\n",
373			selector, max8998->buck2_vol[0], max8998->buck2_vol[1]);
374		if (gpio_is_valid(pdata->buck2_set3)) {
375
376			/* check if requested voltage */
377			/* value is already defined */
378			for (j = 0; j < ARRAY_SIZE(max8998->buck2_vol); j++) {
379				if (max8998->buck2_vol[j] == selector) {
380					max8998->buck2_idx = j;
381					buck2_gpio_set(pdata->buck2_set3, j);
382					goto buck2_exit;
383				}
384			}
385
386			if (pdata->buck_voltage_lock)
387				return -EINVAL;
388
389			max8998_get_voltage_register(rdev,
390					&reg, &shift, &mask);
391			ret = max8998_write_reg(i2c, reg, selector);
392			max8998->buck2_vol[max8998->buck2_idx] = selector;
393			buck2_gpio_set(pdata->buck2_set3, max8998->buck2_idx);
394buck2_exit:
395			dev_dbg(max8998->dev, "%s: SET3:%d\n", i2c->name,
396				gpio_get_value(pdata->buck2_set3));
397		} else {
398			ret = max8998_write_reg(i2c, reg, selector);
399		}
400		break;
401
402	case MAX8998_BUCK3:
403	case MAX8998_BUCK4:
404		ret = max8998_update_reg(i2c, reg, selector<<shift,
405					 mask<<shift);
406		break;
407	}
408
409	return ret;
410}
411
412static int max8998_set_voltage_buck_time_sel(struct regulator_dev *rdev,
413					     unsigned int old_selector,
414					     unsigned int new_selector)
415{
416	struct max8998_data *max8998 = rdev_get_drvdata(rdev);
417	struct i2c_client *i2c = max8998->iodev->i2c;
418	const struct voltage_map_desc *desc;
419	int buck = rdev_get_id(rdev);
420	u8 val = 0;
421	int difference, ret;
422
423	if (buck < MAX8998_BUCK1 || buck > MAX8998_BUCK4)
424		return -EINVAL;
425
426	desc = ldo_voltage_map[buck];
427
428	/* Voltage stabilization */
429	ret = max8998_read_reg(i2c, MAX8998_REG_ONOFF4, &val);
430	if (ret)
431		return ret;
432
433	/* lp3974 hasn't got ENRAMP bit - ramp is assumed as true */
434	/* MAX8998 has ENRAMP bit implemented, so test it*/
435	if (max8998->iodev->type == TYPE_MAX8998 && !(val & MAX8998_ENRAMP))
436		return 0;
437
438	difference = (new_selector - old_selector) * desc->step / 1000;
439	if (difference > 0)
440		return DIV_ROUND_UP(difference, (val & 0x0f) + 1);
441
442	return 0;
443}
444
445static struct regulator_ops max8998_ldo_ops = {
446	.list_voltage		= regulator_list_voltage_linear,
447	.map_voltage		= regulator_map_voltage_linear,
448	.is_enabled		= max8998_ldo_is_enabled,
449	.enable			= max8998_ldo_enable,
450	.disable		= max8998_ldo_disable,
451	.get_voltage_sel	= max8998_get_voltage_sel,
452	.set_voltage_sel	= max8998_set_voltage_ldo_sel,
453};
454
455static struct regulator_ops max8998_buck_ops = {
456	.list_voltage		= regulator_list_voltage_linear,
457	.map_voltage		= regulator_map_voltage_linear,
458	.is_enabled		= max8998_ldo_is_enabled,
459	.enable			= max8998_ldo_enable,
460	.disable		= max8998_ldo_disable,
461	.get_voltage_sel	= max8998_get_voltage_sel,
462	.set_voltage_sel	= max8998_set_voltage_buck_sel,
463	.set_voltage_time_sel	= max8998_set_voltage_buck_time_sel,
464};
465
466static struct regulator_ops max8998_others_ops = {
467	.is_enabled		= max8998_ldo_is_enabled,
468	.enable			= max8998_ldo_enable,
469	.disable		= max8998_ldo_disable,
470};
471
472static struct regulator_desc regulators[] = {
473	{
474		.name		= "LDO2",
475		.id		= MAX8998_LDO2,
476		.ops		= &max8998_ldo_ops,
477		.type		= REGULATOR_VOLTAGE,
478		.owner		= THIS_MODULE,
479	}, {
480		.name		= "LDO3",
481		.id		= MAX8998_LDO3,
482		.ops		= &max8998_ldo_ops,
483		.type		= REGULATOR_VOLTAGE,
484		.owner		= THIS_MODULE,
485	}, {
486		.name		= "LDO4",
487		.id		= MAX8998_LDO4,
488		.ops		= &max8998_ldo_ops,
489		.type		= REGULATOR_VOLTAGE,
490		.owner		= THIS_MODULE,
491	}, {
492		.name		= "LDO5",
493		.id		= MAX8998_LDO5,
494		.ops		= &max8998_ldo_ops,
495		.type		= REGULATOR_VOLTAGE,
496		.owner		= THIS_MODULE,
497	}, {
498		.name		= "LDO6",
499		.id		= MAX8998_LDO6,
500		.ops		= &max8998_ldo_ops,
501		.type		= REGULATOR_VOLTAGE,
502		.owner		= THIS_MODULE,
503	}, {
504		.name		= "LDO7",
505		.id		= MAX8998_LDO7,
506		.ops		= &max8998_ldo_ops,
507		.type		= REGULATOR_VOLTAGE,
508		.owner		= THIS_MODULE,
509	}, {
510		.name		= "LDO8",
511		.id		= MAX8998_LDO8,
512		.ops		= &max8998_ldo_ops,
513		.type		= REGULATOR_VOLTAGE,
514		.owner		= THIS_MODULE,
515	}, {
516		.name		= "LDO9",
517		.id		= MAX8998_LDO9,
518		.ops		= &max8998_ldo_ops,
519		.type		= REGULATOR_VOLTAGE,
520		.owner		= THIS_MODULE,
521	}, {
522		.name		= "LDO10",
523		.id		= MAX8998_LDO10,
524		.ops		= &max8998_ldo_ops,
525		.type		= REGULATOR_VOLTAGE,
526		.owner		= THIS_MODULE,
527	}, {
528		.name		= "LDO11",
529		.id		= MAX8998_LDO11,
530		.ops		= &max8998_ldo_ops,
531		.type		= REGULATOR_VOLTAGE,
532		.owner		= THIS_MODULE,
533	}, {
534		.name		= "LDO12",
535		.id		= MAX8998_LDO12,
536		.ops		= &max8998_ldo_ops,
537		.type		= REGULATOR_VOLTAGE,
538		.owner		= THIS_MODULE,
539	}, {
540		.name		= "LDO13",
541		.id		= MAX8998_LDO13,
542		.ops		= &max8998_ldo_ops,
543		.type		= REGULATOR_VOLTAGE,
544		.owner		= THIS_MODULE,
545	}, {
546		.name		= "LDO14",
547		.id		= MAX8998_LDO14,
548		.ops		= &max8998_ldo_ops,
549		.type		= REGULATOR_VOLTAGE,
550		.owner		= THIS_MODULE,
551	}, {
552		.name		= "LDO15",
553		.id		= MAX8998_LDO15,
554		.ops		= &max8998_ldo_ops,
555		.type		= REGULATOR_VOLTAGE,
556		.owner		= THIS_MODULE,
557	}, {
558		.name		= "LDO16",
559		.id		= MAX8998_LDO16,
560		.ops		= &max8998_ldo_ops,
561		.type		= REGULATOR_VOLTAGE,
562		.owner		= THIS_MODULE,
563	}, {
564		.name		= "LDO17",
565		.id		= MAX8998_LDO17,
566		.ops		= &max8998_ldo_ops,
567		.type		= REGULATOR_VOLTAGE,
568		.owner		= THIS_MODULE,
569	}, {
570		.name		= "BUCK1",
571		.id		= MAX8998_BUCK1,
572		.ops		= &max8998_buck_ops,
573		.type		= REGULATOR_VOLTAGE,
574		.owner		= THIS_MODULE,
575	}, {
576		.name		= "BUCK2",
577		.id		= MAX8998_BUCK2,
578		.ops		= &max8998_buck_ops,
579		.type		= REGULATOR_VOLTAGE,
580		.owner		= THIS_MODULE,
581	}, {
582		.name		= "BUCK3",
583		.id		= MAX8998_BUCK3,
584		.ops		= &max8998_buck_ops,
585		.type		= REGULATOR_VOLTAGE,
586		.owner		= THIS_MODULE,
587	}, {
588		.name		= "BUCK4",
589		.id		= MAX8998_BUCK4,
590		.ops		= &max8998_buck_ops,
591		.type		= REGULATOR_VOLTAGE,
592		.owner		= THIS_MODULE,
593	}, {
594		.name		= "EN32KHz-AP",
595		.id		= MAX8998_EN32KHZ_AP,
596		.ops		= &max8998_others_ops,
597		.type		= REGULATOR_VOLTAGE,
598		.owner		= THIS_MODULE,
599	}, {
600		.name		= "EN32KHz-CP",
601		.id		= MAX8998_EN32KHZ_CP,
602		.ops		= &max8998_others_ops,
603		.type		= REGULATOR_VOLTAGE,
604		.owner		= THIS_MODULE,
605	}, {
606		.name		= "ENVICHG",
607		.id		= MAX8998_ENVICHG,
608		.ops		= &max8998_others_ops,
609		.type		= REGULATOR_VOLTAGE,
610		.owner		= THIS_MODULE,
611	}, {
612		.name		= "ESAFEOUT1",
613		.id		= MAX8998_ESAFEOUT1,
614		.ops		= &max8998_others_ops,
615		.type		= REGULATOR_VOLTAGE,
616		.owner		= THIS_MODULE,
617	}, {
618		.name		= "ESAFEOUT2",
619		.id		= MAX8998_ESAFEOUT2,
620		.ops		= &max8998_others_ops,
621		.type		= REGULATOR_VOLTAGE,
622		.owner		= THIS_MODULE,
623	}
624};
625
626static int max8998_pmic_dt_parse_dvs_gpio(struct max8998_dev *iodev,
627			struct max8998_platform_data *pdata,
628			struct device_node *pmic_np)
629{
630	int gpio;
631
632	gpio = of_get_named_gpio(pmic_np, "max8998,pmic-buck1-dvs-gpios", 0);
633	if (!gpio_is_valid(gpio)) {
634		dev_err(iodev->dev, "invalid buck1 gpio[0]: %d\n", gpio);
635		return -EINVAL;
636	}
637	pdata->buck1_set1 = gpio;
638
639	gpio = of_get_named_gpio(pmic_np, "max8998,pmic-buck1-dvs-gpios", 1);
640	if (!gpio_is_valid(gpio)) {
641		dev_err(iodev->dev, "invalid buck1 gpio[1]: %d\n", gpio);
642		return -EINVAL;
643	}
644	pdata->buck1_set2 = gpio;
645
646	gpio = of_get_named_gpio(pmic_np, "max8998,pmic-buck2-dvs-gpio", 0);
647	if (!gpio_is_valid(gpio)) {
648		dev_err(iodev->dev, "invalid buck 2 gpio: %d\n", gpio);
649		return -EINVAL;
650	}
651	pdata->buck2_set3 = gpio;
652
653	return 0;
654}
655
656static int max8998_pmic_dt_parse_pdata(struct max8998_dev *iodev,
657					struct max8998_platform_data *pdata)
658{
659	struct device_node *pmic_np = iodev->dev->of_node;
660	struct device_node *regulators_np, *reg_np;
661	struct max8998_regulator_data *rdata;
662	unsigned int i;
663	int ret;
664
665	regulators_np = of_get_child_by_name(pmic_np, "regulators");
666	if (!regulators_np) {
667		dev_err(iodev->dev, "could not find regulators sub-node\n");
668		return -EINVAL;
669	}
670
671	/* count the number of regulators to be supported in pmic */
672	pdata->num_regulators = of_get_child_count(regulators_np);
673
674	rdata = devm_kzalloc(iodev->dev, sizeof(*rdata) *
675				pdata->num_regulators, GFP_KERNEL);
676	if (!rdata) {
677		of_node_put(regulators_np);
678		return -ENOMEM;
679	}
680
681	pdata->regulators = rdata;
682	for (i = 0; i < ARRAY_SIZE(regulators); ++i) {
683		reg_np = of_get_child_by_name(regulators_np,
684							regulators[i].name);
685		if (!reg_np)
686			continue;
687
688		rdata->id = regulators[i].id;
689		rdata->initdata = of_get_regulator_init_data(iodev->dev,
690							     reg_np,
691							     &regulators[i]);
692		rdata->reg_node = reg_np;
693		++rdata;
694	}
695	pdata->num_regulators = rdata - pdata->regulators;
696
697	of_node_put(reg_np);
698	of_node_put(regulators_np);
699
700	ret = max8998_pmic_dt_parse_dvs_gpio(iodev, pdata, pmic_np);
701	if (ret)
702		return -EINVAL;
703
704	if (of_find_property(pmic_np, "max8998,pmic-buck-voltage-lock", NULL))
705		pdata->buck_voltage_lock = true;
706
707	ret = of_property_read_u32(pmic_np,
708					"max8998,pmic-buck1-default-dvs-idx",
709					&pdata->buck1_default_idx);
710	if (!ret && pdata->buck1_default_idx >= 4) {
711		pdata->buck1_default_idx = 0;
712		dev_warn(iodev->dev, "invalid value for default dvs index, using 0 instead\n");
713	}
714
715	ret = of_property_read_u32(pmic_np,
716					"max8998,pmic-buck2-default-dvs-idx",
717					&pdata->buck2_default_idx);
718	if (!ret && pdata->buck2_default_idx >= 2) {
719		pdata->buck2_default_idx = 0;
720		dev_warn(iodev->dev, "invalid value for default dvs index, using 0 instead\n");
721	}
722
723	ret = of_property_read_u32_array(pmic_np,
724					"max8998,pmic-buck1-dvs-voltage",
725					pdata->buck1_voltage,
726					ARRAY_SIZE(pdata->buck1_voltage));
727	if (ret) {
728		dev_err(iodev->dev, "buck1 voltages not specified\n");
729		return -EINVAL;
730	}
731
732	ret = of_property_read_u32_array(pmic_np,
733					"max8998,pmic-buck2-dvs-voltage",
734					pdata->buck2_voltage,
735					ARRAY_SIZE(pdata->buck2_voltage));
736	if (ret) {
737		dev_err(iodev->dev, "buck2 voltages not specified\n");
738		return -EINVAL;
739	}
740
741	return 0;
742}
743
744static int max8998_pmic_probe(struct platform_device *pdev)
745{
746	struct max8998_dev *iodev = dev_get_drvdata(pdev->dev.parent);
747	struct max8998_platform_data *pdata = iodev->pdata;
748	struct regulator_config config = { };
749	struct regulator_dev *rdev;
750	struct max8998_data *max8998;
751	struct i2c_client *i2c;
752	int i, ret;
753	unsigned int v;
754
755	if (!pdata) {
756		dev_err(pdev->dev.parent, "No platform init data supplied\n");
757		return -ENODEV;
758	}
759
760	if (IS_ENABLED(CONFIG_OF) && iodev->dev->of_node) {
761		ret = max8998_pmic_dt_parse_pdata(iodev, pdata);
762		if (ret)
763			return ret;
764	}
765
766	max8998 = devm_kzalloc(&pdev->dev, sizeof(struct max8998_data),
767			       GFP_KERNEL);
768	if (!max8998)
769		return -ENOMEM;
770
771	max8998->dev = &pdev->dev;
772	max8998->iodev = iodev;
773	max8998->num_regulators = pdata->num_regulators;
774	platform_set_drvdata(pdev, max8998);
775	i2c = max8998->iodev->i2c;
776
777	max8998->buck1_idx = pdata->buck1_default_idx;
778	max8998->buck2_idx = pdata->buck2_default_idx;
779
780	/* NOTE: */
781	/* For unused GPIO NOT marked as -1 (thereof equal to 0)  WARN_ON */
782	/* will be displayed */
783
784	/* Check if MAX8998 voltage selection GPIOs are defined */
785	if (gpio_is_valid(pdata->buck1_set1) &&
786	    gpio_is_valid(pdata->buck1_set2)) {
787		/* Check if SET1 is not equal to 0 */
788		if (!pdata->buck1_set1) {
789			dev_err(&pdev->dev,
790				"MAX8998 SET1 GPIO defined as 0 !\n");
791			WARN_ON(!pdata->buck1_set1);
792			return -EIO;
793		}
794		/* Check if SET2 is not equal to 0 */
795		if (!pdata->buck1_set2) {
796			dev_err(&pdev->dev,
797				"MAX8998 SET2 GPIO defined as 0 !\n");
798			WARN_ON(!pdata->buck1_set2);
799			return -EIO;
800		}
801
802		gpio_request(pdata->buck1_set1, "MAX8998 BUCK1_SET1");
803		gpio_direction_output(pdata->buck1_set1,
804				      max8998->buck1_idx & 0x1);
805
806
807		gpio_request(pdata->buck1_set2, "MAX8998 BUCK1_SET2");
808		gpio_direction_output(pdata->buck1_set2,
809				      (max8998->buck1_idx >> 1) & 0x1);
810
811		/* Set predefined values for BUCK1 registers */
812		for (v = 0; v < ARRAY_SIZE(pdata->buck1_voltage); ++v) {
813			i = 0;
814			while (buck12_voltage_map_desc.min +
815			       buck12_voltage_map_desc.step*i
816			       < pdata->buck1_voltage[v])
817				i++;
818
819			max8998->buck1_vol[v] = i;
820			ret = max8998_write_reg(i2c,
821					MAX8998_REG_BUCK1_VOLTAGE1 + v, i);
822			if (ret)
823				return ret;
824		}
825	}
826
827	if (gpio_is_valid(pdata->buck2_set3)) {
828		/* Check if SET3 is not equal to 0 */
829		if (!pdata->buck2_set3) {
830			dev_err(&pdev->dev,
831				"MAX8998 SET3 GPIO defined as 0 !\n");
832			WARN_ON(!pdata->buck2_set3);
833			return -EIO;
834		}
835		gpio_request(pdata->buck2_set3, "MAX8998 BUCK2_SET3");
836		gpio_direction_output(pdata->buck2_set3,
837				      max8998->buck2_idx & 0x1);
838
839		/* Set predefined values for BUCK2 registers */
840		for (v = 0; v < ARRAY_SIZE(pdata->buck2_voltage); ++v) {
841			i = 0;
842			while (buck12_voltage_map_desc.min +
843			       buck12_voltage_map_desc.step*i
844			       < pdata->buck2_voltage[v])
845				i++;
846
847			max8998->buck2_vol[v] = i;
848			ret = max8998_write_reg(i2c,
849					MAX8998_REG_BUCK2_VOLTAGE1 + v, i);
850			if (ret)
851				return ret;
852		}
853	}
854
855	for (i = 0; i < pdata->num_regulators; i++) {
856		const struct voltage_map_desc *desc;
857		int id = pdata->regulators[i].id;
858		int index = id - MAX8998_LDO2;
859
860		desc = ldo_voltage_map[id];
861		if (desc && regulators[index].ops != &max8998_others_ops) {
862			int count = (desc->max - desc->min) / desc->step + 1;
863
864			regulators[index].n_voltages = count;
865			regulators[index].min_uV = desc->min;
866			regulators[index].uV_step = desc->step;
867		}
868
869		config.dev = max8998->dev;
870		config.of_node = pdata->regulators[i].reg_node;
871		config.init_data = pdata->regulators[i].initdata;
872		config.driver_data = max8998;
873
874		rdev = devm_regulator_register(&pdev->dev, &regulators[index],
875					       &config);
876		if (IS_ERR(rdev)) {
877			ret = PTR_ERR(rdev);
878			dev_err(max8998->dev, "regulator %s init failed (%d)\n",
879						regulators[index].name, ret);
880			return ret;
881		}
882	}
883
884
885	return 0;
886}
887
888static const struct platform_device_id max8998_pmic_id[] = {
889	{ "max8998-pmic", TYPE_MAX8998 },
890	{ "lp3974-pmic", TYPE_LP3974 },
891	{ }
892};
893MODULE_DEVICE_TABLE(platform, max8998_pmic_id);
894
895static struct platform_driver max8998_pmic_driver = {
896	.driver = {
897		.name = "max8998-pmic",
898	},
899	.probe = max8998_pmic_probe,
900	.id_table = max8998_pmic_id,
901};
902
903static int __init max8998_pmic_init(void)
904{
905	return platform_driver_register(&max8998_pmic_driver);
906}
907subsys_initcall(max8998_pmic_init);
908
909static void __exit max8998_pmic_cleanup(void)
910{
911	platform_driver_unregister(&max8998_pmic_driver);
912}
913module_exit(max8998_pmic_cleanup);
914
915MODULE_DESCRIPTION("MAXIM 8998 voltage regulator driver");
916MODULE_AUTHOR("Kyungmin Park <kyungmin.park@samsung.com>");
917MODULE_LICENSE("GPL");
918