xref: /linux/drivers/mfd/max14577.c (revision cc04a46f11ea046ed53e2c832ae29e4790f7e35f)
1 /*
2  * max14577.c - mfd core driver for the Maxim 14577/77836
3  *
4  * Copyright (C) 2014 Samsung Electronics
5  * Chanwoo Choi <cw00.choi@samsung.com>
6  * Krzysztof Kozlowski <k.kozlowski@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  * This driver is based on max8997.c
19  */
20 
21 #include <linux/err.h>
22 #include <linux/module.h>
23 #include <linux/interrupt.h>
24 #include <linux/of_device.h>
25 #include <linux/mfd/core.h>
26 #include <linux/mfd/max14577.h>
27 #include <linux/mfd/max14577-private.h>
28 
29 /*
30  * Table of valid charger currents for different Maxim chipsets.
31  * It is placed here because it is used by both charger and regulator driver.
32  */
33 const struct maxim_charger_current maxim_charger_currents[] = {
34 	[MAXIM_DEVICE_TYPE_UNKNOWN] = { 0, 0, 0, 0 },
35 	[MAXIM_DEVICE_TYPE_MAX14577] = {
36 		.min		= MAX14577_CHARGER_CURRENT_LIMIT_MIN,
37 		.high_start	= MAX14577_CHARGER_CURRENT_LIMIT_HIGH_START,
38 		.high_step	= MAX14577_CHARGER_CURRENT_LIMIT_HIGH_STEP,
39 		.max		= MAX14577_CHARGER_CURRENT_LIMIT_MAX,
40 	},
41 	[MAXIM_DEVICE_TYPE_MAX77836] = {
42 		.min		= MAX77836_CHARGER_CURRENT_LIMIT_MIN,
43 		.high_start	= MAX77836_CHARGER_CURRENT_LIMIT_HIGH_START,
44 		.high_step	= MAX77836_CHARGER_CURRENT_LIMIT_HIGH_STEP,
45 		.max		= MAX77836_CHARGER_CURRENT_LIMIT_MAX,
46 	},
47 };
48 EXPORT_SYMBOL_GPL(maxim_charger_currents);
49 
50 /*
51  * maxim_charger_calc_reg_current - Calculate register value for current
52  * @limits:	constraints for charger, matching the MBCICHWRC register
53  * @min_ua:	minimal requested current, micro Amps
54  * @max_ua:	maximum requested current, micro Amps
55  * @dst:	destination to store calculated register value
56  *
57  * Calculates the value of MBCICHWRC (Fast Battery Charge Current) register
58  * for given current and stores it under pointed 'dst'. The stored value
59  * combines low bit (MBCICHWRCL) and high bits (MBCICHWRCH). It is also
60  * properly shifted.
61  *
62  * The calculated register value matches the current which:
63  *  - is always between <limits.min, limits.max>;
64  *  - is always less or equal to max_ua;
65  *  - is the highest possible value;
66  *  - may be lower than min_ua.
67  *
68  * On success returns 0. On error returns -EINVAL (requested min/max current
69  * is outside of given charger limits) and 'dst' is not set.
70  */
71 int maxim_charger_calc_reg_current(const struct maxim_charger_current *limits,
72 		unsigned int min_ua, unsigned int max_ua, u8 *dst)
73 {
74 	unsigned int current_bits = 0xf;
75 
76 	if (min_ua > max_ua)
77 		return -EINVAL;
78 
79 	if (min_ua > limits->max || max_ua < limits->min)
80 		return -EINVAL;
81 
82 	if (max_ua < limits->high_start) {
83 		/*
84 		 * Less than high_start, so set the minimal current
85 		 * (turn Low Bit off, 0 as high bits).
86 		 */
87 		*dst = 0x0;
88 		return 0;
89 	}
90 
91 	/* max_ua is in range: <high_start, infinite>, cut it to limits.max */
92 	max_ua = min(limits->max, max_ua);
93 	max_ua -= limits->high_start;
94 	/*
95 	 * There is no risk of overflow 'max_ua' here because:
96 	 *  - max_ua >= limits.high_start
97 	 *  - BUILD_BUG checks that 'limits' are: max >= high_start + high_step
98 	 */
99 	current_bits = max_ua / limits->high_step;
100 
101 	/* Turn Low Bit on (use range <limits.high_start, limits.max>) ... */
102 	*dst = 0x1 << CHGCTRL4_MBCICHWRCL_SHIFT;
103 	/* and set proper High Bits */
104 	*dst |= current_bits << CHGCTRL4_MBCICHWRCH_SHIFT;
105 
106 	return 0;
107 }
108 EXPORT_SYMBOL_GPL(maxim_charger_calc_reg_current);
109 
110 static const struct mfd_cell max14577_devs[] = {
111 	{
112 		.name = "max14577-muic",
113 		.of_compatible = "maxim,max14577-muic",
114 	},
115 	{
116 		.name = "max14577-regulator",
117 		.of_compatible = "maxim,max14577-regulator",
118 	},
119 	{
120 		.name = "max14577-charger",
121 		.of_compatible = "maxim,max14577-charger",
122 	},
123 };
124 
125 static const struct mfd_cell max77836_devs[] = {
126 	{
127 		.name = "max77836-muic",
128 		.of_compatible = "maxim,max77836-muic",
129 	},
130 	{
131 		.name = "max77836-regulator",
132 		.of_compatible = "maxim,max77836-regulator",
133 	},
134 	{
135 		.name = "max77836-charger",
136 		.of_compatible = "maxim,max77836-charger",
137 	},
138 	{
139 		.name = "max77836-battery",
140 		.of_compatible = "maxim,max77836-battery",
141 	},
142 };
143 
144 static const struct of_device_id max14577_dt_match[] = {
145 	{
146 		.compatible = "maxim,max14577",
147 		.data = (void *)MAXIM_DEVICE_TYPE_MAX14577,
148 	},
149 	{
150 		.compatible = "maxim,max77836",
151 		.data = (void *)MAXIM_DEVICE_TYPE_MAX77836,
152 	},
153 	{},
154 };
155 
156 static bool max14577_muic_volatile_reg(struct device *dev, unsigned int reg)
157 {
158 	switch (reg) {
159 	case MAX14577_REG_INT1 ... MAX14577_REG_STATUS3:
160 		return true;
161 	default:
162 		break;
163 	}
164 	return false;
165 }
166 
167 static bool max77836_muic_volatile_reg(struct device *dev, unsigned int reg)
168 {
169 	/* Any max14577 volatile registers are also max77836 volatile. */
170 	if (max14577_muic_volatile_reg(dev, reg))
171 		return true;
172 
173 	switch (reg) {
174 	case MAX77836_FG_REG_VCELL_MSB ... MAX77836_FG_REG_SOC_LSB:
175 	case MAX77836_FG_REG_CRATE_MSB ... MAX77836_FG_REG_CRATE_LSB:
176 	case MAX77836_FG_REG_STATUS_H ... MAX77836_FG_REG_STATUS_L:
177 	case MAX77836_PMIC_REG_INTSRC:
178 	case MAX77836_PMIC_REG_TOPSYS_INT:
179 	case MAX77836_PMIC_REG_TOPSYS_STAT:
180 		return true;
181 	default:
182 		break;
183 	}
184 	return false;
185 }
186 
187 static const struct regmap_config max14577_muic_regmap_config = {
188 	.reg_bits	= 8,
189 	.val_bits	= 8,
190 	.volatile_reg	= max14577_muic_volatile_reg,
191 	.max_register	= MAX14577_REG_END,
192 };
193 
194 static const struct regmap_config max77836_pmic_regmap_config = {
195 	.reg_bits	= 8,
196 	.val_bits	= 8,
197 	.volatile_reg	= max77836_muic_volatile_reg,
198 	.max_register	= MAX77836_PMIC_REG_END,
199 };
200 
201 static const struct regmap_irq max14577_irqs[] = {
202 	/* INT1 interrupts */
203 	{ .reg_offset = 0, .mask = MAX14577_INT1_ADC_MASK, },
204 	{ .reg_offset = 0, .mask = MAX14577_INT1_ADCLOW_MASK, },
205 	{ .reg_offset = 0, .mask = MAX14577_INT1_ADCERR_MASK, },
206 	/* INT2 interrupts */
207 	{ .reg_offset = 1, .mask = MAX14577_INT2_CHGTYP_MASK, },
208 	{ .reg_offset = 1, .mask = MAX14577_INT2_CHGDETRUN_MASK, },
209 	{ .reg_offset = 1, .mask = MAX14577_INT2_DCDTMR_MASK, },
210 	{ .reg_offset = 1, .mask = MAX14577_INT2_DBCHG_MASK, },
211 	{ .reg_offset = 1, .mask = MAX14577_INT2_VBVOLT_MASK, },
212 	/* INT3 interrupts */
213 	{ .reg_offset = 2, .mask = MAX14577_INT3_EOC_MASK, },
214 	{ .reg_offset = 2, .mask = MAX14577_INT3_CGMBC_MASK, },
215 	{ .reg_offset = 2, .mask = MAX14577_INT3_OVP_MASK, },
216 	{ .reg_offset = 2, .mask = MAX14577_INT3_MBCCHGERR_MASK, },
217 };
218 
219 static const struct regmap_irq_chip max14577_irq_chip = {
220 	.name			= "max14577",
221 	.status_base		= MAX14577_REG_INT1,
222 	.mask_base		= MAX14577_REG_INTMASK1,
223 	.mask_invert		= true,
224 	.num_regs		= 3,
225 	.irqs			= max14577_irqs,
226 	.num_irqs		= ARRAY_SIZE(max14577_irqs),
227 };
228 
229 static const struct regmap_irq max77836_muic_irqs[] = {
230 	/* INT1 interrupts */
231 	{ .reg_offset = 0, .mask = MAX14577_INT1_ADC_MASK, },
232 	{ .reg_offset = 0, .mask = MAX14577_INT1_ADCLOW_MASK, },
233 	{ .reg_offset = 0, .mask = MAX14577_INT1_ADCERR_MASK, },
234 	{ .reg_offset = 0, .mask = MAX77836_INT1_ADC1K_MASK, },
235 	/* INT2 interrupts */
236 	{ .reg_offset = 1, .mask = MAX14577_INT2_CHGTYP_MASK, },
237 	{ .reg_offset = 1, .mask = MAX14577_INT2_CHGDETRUN_MASK, },
238 	{ .reg_offset = 1, .mask = MAX14577_INT2_DCDTMR_MASK, },
239 	{ .reg_offset = 1, .mask = MAX14577_INT2_DBCHG_MASK, },
240 	{ .reg_offset = 1, .mask = MAX14577_INT2_VBVOLT_MASK, },
241 	{ .reg_offset = 1, .mask = MAX77836_INT2_VIDRM_MASK, },
242 	/* INT3 interrupts */
243 	{ .reg_offset = 2, .mask = MAX14577_INT3_EOC_MASK, },
244 	{ .reg_offset = 2, .mask = MAX14577_INT3_CGMBC_MASK, },
245 	{ .reg_offset = 2, .mask = MAX14577_INT3_OVP_MASK, },
246 	{ .reg_offset = 2, .mask = MAX14577_INT3_MBCCHGERR_MASK, },
247 };
248 
249 static const struct regmap_irq_chip max77836_muic_irq_chip = {
250 	.name			= "max77836-muic",
251 	.status_base		= MAX14577_REG_INT1,
252 	.mask_base		= MAX14577_REG_INTMASK1,
253 	.mask_invert		= true,
254 	.num_regs		= 3,
255 	.irqs			= max77836_muic_irqs,
256 	.num_irqs		= ARRAY_SIZE(max77836_muic_irqs),
257 };
258 
259 static const struct regmap_irq max77836_pmic_irqs[] = {
260 	{ .reg_offset = 0, .mask = MAX77836_TOPSYS_INT_T120C_MASK, },
261 	{ .reg_offset = 0, .mask = MAX77836_TOPSYS_INT_T140C_MASK, },
262 };
263 
264 static const struct regmap_irq_chip max77836_pmic_irq_chip = {
265 	.name			= "max77836-pmic",
266 	.status_base		= MAX77836_PMIC_REG_TOPSYS_INT,
267 	.mask_base		= MAX77836_PMIC_REG_TOPSYS_INT_MASK,
268 	.mask_invert		= false,
269 	.num_regs		= 1,
270 	.irqs			= max77836_pmic_irqs,
271 	.num_irqs		= ARRAY_SIZE(max77836_pmic_irqs),
272 };
273 
274 static void max14577_print_dev_type(struct max14577 *max14577)
275 {
276 	u8 reg_data, vendor_id, device_id;
277 	int ret;
278 
279 	ret = max14577_read_reg(max14577->regmap, MAX14577_REG_DEVICEID,
280 			&reg_data);
281 	if (ret) {
282 		dev_err(max14577->dev,
283 			"Failed to read DEVICEID register: %d\n", ret);
284 		return;
285 	}
286 
287 	vendor_id = ((reg_data & DEVID_VENDORID_MASK) >>
288 				DEVID_VENDORID_SHIFT);
289 	device_id = ((reg_data & DEVID_DEVICEID_MASK) >>
290 				DEVID_DEVICEID_SHIFT);
291 
292 	dev_info(max14577->dev, "Device type: %u (ID: 0x%x, vendor: 0x%x)\n",
293 			max14577->dev_type, device_id, vendor_id);
294 }
295 
296 /*
297  * Max77836 specific initialization code for driver probe.
298  * Adds new I2C dummy device, regmap and regmap IRQ chip.
299  * Unmasks Interrupt Source register.
300  *
301  * On success returns 0.
302  * On failure returns errno and reverts any changes done so far (e.g. remove
303  * I2C dummy device), except masking the INT SRC register.
304  */
305 static int max77836_init(struct max14577 *max14577)
306 {
307 	int ret;
308 	u8 intsrc_mask;
309 
310 	max14577->i2c_pmic = i2c_new_dummy(max14577->i2c->adapter,
311 			I2C_ADDR_PMIC);
312 	if (!max14577->i2c_pmic) {
313 		dev_err(max14577->dev, "Failed to register PMIC I2C device\n");
314 		return -ENODEV;
315 	}
316 	i2c_set_clientdata(max14577->i2c_pmic, max14577);
317 
318 	max14577->regmap_pmic = devm_regmap_init_i2c(max14577->i2c_pmic,
319 			&max77836_pmic_regmap_config);
320 	if (IS_ERR(max14577->regmap_pmic)) {
321 		ret = PTR_ERR(max14577->regmap_pmic);
322 		dev_err(max14577->dev, "Failed to allocate PMIC register map: %d\n",
323 				ret);
324 		goto err;
325 	}
326 
327 	/* Un-mask MAX77836 Interrupt Source register */
328 	ret = max14577_read_reg(max14577->regmap_pmic,
329 			MAX77836_PMIC_REG_INTSRC_MASK, &intsrc_mask);
330 	if (ret < 0) {
331 		dev_err(max14577->dev, "Failed to read PMIC register\n");
332 		goto err;
333 	}
334 
335 	intsrc_mask &= ~(MAX77836_INTSRC_MASK_TOP_INT_MASK);
336 	intsrc_mask &= ~(MAX77836_INTSRC_MASK_MUIC_CHG_INT_MASK);
337 	ret = max14577_write_reg(max14577->regmap_pmic,
338 			MAX77836_PMIC_REG_INTSRC_MASK, intsrc_mask);
339 	if (ret < 0) {
340 		dev_err(max14577->dev, "Failed to write PMIC register\n");
341 		goto err;
342 	}
343 
344 	ret = regmap_add_irq_chip(max14577->regmap_pmic, max14577->irq,
345 			IRQF_TRIGGER_FALLING | IRQF_ONESHOT | IRQF_SHARED,
346 			0, &max77836_pmic_irq_chip,
347 			&max14577->irq_data_pmic);
348 	if (ret != 0) {
349 		dev_err(max14577->dev, "Failed to request PMIC IRQ %d: %d\n",
350 				max14577->irq, ret);
351 		goto err;
352 	}
353 
354 	return 0;
355 
356 err:
357 	i2c_unregister_device(max14577->i2c_pmic);
358 
359 	return ret;
360 }
361 
362 /*
363  * Max77836 specific de-initialization code for driver remove.
364  */
365 static void max77836_remove(struct max14577 *max14577)
366 {
367 	regmap_del_irq_chip(max14577->irq, max14577->irq_data_pmic);
368 	i2c_unregister_device(max14577->i2c_pmic);
369 }
370 
371 static int max14577_i2c_probe(struct i2c_client *i2c,
372 			      const struct i2c_device_id *id)
373 {
374 	struct max14577 *max14577;
375 	struct max14577_platform_data *pdata = dev_get_platdata(&i2c->dev);
376 	struct device_node *np = i2c->dev.of_node;
377 	int ret = 0;
378 	const struct regmap_irq_chip *irq_chip;
379 	const struct mfd_cell *mfd_devs;
380 	unsigned int mfd_devs_size;
381 	int irq_flags;
382 
383 	if (np) {
384 		pdata = devm_kzalloc(&i2c->dev, sizeof(*pdata), GFP_KERNEL);
385 		if (!pdata)
386 			return -ENOMEM;
387 		i2c->dev.platform_data = pdata;
388 	}
389 
390 	if (!pdata) {
391 		dev_err(&i2c->dev, "No platform data found.\n");
392 		return -EINVAL;
393 	}
394 
395 	max14577 = devm_kzalloc(&i2c->dev, sizeof(*max14577), GFP_KERNEL);
396 	if (!max14577)
397 		return -ENOMEM;
398 
399 	i2c_set_clientdata(i2c, max14577);
400 	max14577->dev = &i2c->dev;
401 	max14577->i2c = i2c;
402 	max14577->irq = i2c->irq;
403 
404 	max14577->regmap = devm_regmap_init_i2c(i2c,
405 			&max14577_muic_regmap_config);
406 	if (IS_ERR(max14577->regmap)) {
407 		ret = PTR_ERR(max14577->regmap);
408 		dev_err(max14577->dev, "Failed to allocate register map: %d\n",
409 				ret);
410 		return ret;
411 	}
412 
413 	if (np) {
414 		const struct of_device_id *of_id;
415 
416 		of_id = of_match_device(max14577_dt_match, &i2c->dev);
417 		if (of_id)
418 			max14577->dev_type =
419 				(enum maxim_device_type)of_id->data;
420 	} else {
421 		max14577->dev_type = id->driver_data;
422 	}
423 
424 	max14577_print_dev_type(max14577);
425 
426 	switch (max14577->dev_type) {
427 	case MAXIM_DEVICE_TYPE_MAX77836:
428 		irq_chip = &max77836_muic_irq_chip;
429 		mfd_devs = max77836_devs;
430 		mfd_devs_size = ARRAY_SIZE(max77836_devs);
431 		irq_flags = IRQF_TRIGGER_FALLING | IRQF_ONESHOT | IRQF_SHARED;
432 		break;
433 	case MAXIM_DEVICE_TYPE_MAX14577:
434 	default:
435 		irq_chip = &max14577_irq_chip;
436 		mfd_devs = max14577_devs;
437 		mfd_devs_size = ARRAY_SIZE(max14577_devs);
438 		irq_flags = IRQF_TRIGGER_FALLING | IRQF_ONESHOT;
439 		break;
440 	}
441 
442 	ret = regmap_add_irq_chip(max14577->regmap, max14577->irq,
443 				  irq_flags, 0, irq_chip,
444 				  &max14577->irq_data);
445 	if (ret != 0) {
446 		dev_err(&i2c->dev, "Failed to request IRQ %d: %d\n",
447 				max14577->irq, ret);
448 		return ret;
449 	}
450 
451 	/* Max77836 specific initialization code (additional regmap) */
452 	if (max14577->dev_type == MAXIM_DEVICE_TYPE_MAX77836) {
453 		ret = max77836_init(max14577);
454 		if (ret < 0)
455 			goto err_max77836;
456 	}
457 
458 	ret = mfd_add_devices(max14577->dev, -1, mfd_devs,
459 			mfd_devs_size, NULL, 0, NULL);
460 	if (ret < 0)
461 		goto err_mfd;
462 
463 	device_init_wakeup(max14577->dev, 1);
464 
465 	return 0;
466 
467 err_mfd:
468 	if (max14577->dev_type == MAXIM_DEVICE_TYPE_MAX77836)
469 		max77836_remove(max14577);
470 err_max77836:
471 	regmap_del_irq_chip(max14577->irq, max14577->irq_data);
472 
473 	return ret;
474 }
475 
476 static int max14577_i2c_remove(struct i2c_client *i2c)
477 {
478 	struct max14577 *max14577 = i2c_get_clientdata(i2c);
479 
480 	mfd_remove_devices(max14577->dev);
481 	regmap_del_irq_chip(max14577->irq, max14577->irq_data);
482 	if (max14577->dev_type == MAXIM_DEVICE_TYPE_MAX77836)
483 		max77836_remove(max14577);
484 
485 	return 0;
486 }
487 
488 static const struct i2c_device_id max14577_i2c_id[] = {
489 	{ "max14577", MAXIM_DEVICE_TYPE_MAX14577, },
490 	{ "max77836", MAXIM_DEVICE_TYPE_MAX77836, },
491 	{ }
492 };
493 MODULE_DEVICE_TABLE(i2c, max14577_i2c_id);
494 
495 #ifdef CONFIG_PM_SLEEP
496 static int max14577_suspend(struct device *dev)
497 {
498 	struct i2c_client *i2c = container_of(dev, struct i2c_client, dev);
499 	struct max14577 *max14577 = i2c_get_clientdata(i2c);
500 
501 	if (device_may_wakeup(dev))
502 		enable_irq_wake(max14577->irq);
503 	/*
504 	 * MUIC IRQ must be disabled during suspend because if it happens
505 	 * while suspended it will be handled before resuming I2C.
506 	 *
507 	 * When device is woken up from suspend (e.g. by ADC change),
508 	 * an interrupt occurs before resuming I2C bus controller.
509 	 * Interrupt handler tries to read registers but this read
510 	 * will fail because I2C is still suspended.
511 	 */
512 	disable_irq(max14577->irq);
513 
514 	return 0;
515 }
516 
517 static int max14577_resume(struct device *dev)
518 {
519 	struct i2c_client *i2c = container_of(dev, struct i2c_client, dev);
520 	struct max14577 *max14577 = i2c_get_clientdata(i2c);
521 
522 	if (device_may_wakeup(dev))
523 		disable_irq_wake(max14577->irq);
524 	enable_irq(max14577->irq);
525 
526 	return 0;
527 }
528 #endif /* CONFIG_PM_SLEEP */
529 
530 static SIMPLE_DEV_PM_OPS(max14577_pm, max14577_suspend, max14577_resume);
531 
532 static struct i2c_driver max14577_i2c_driver = {
533 	.driver = {
534 		.name = "max14577",
535 		.pm = &max14577_pm,
536 		.of_match_table = max14577_dt_match,
537 	},
538 	.probe = max14577_i2c_probe,
539 	.remove = max14577_i2c_remove,
540 	.id_table = max14577_i2c_id,
541 };
542 
543 static int __init max14577_i2c_init(void)
544 {
545 	BUILD_BUG_ON(ARRAY_SIZE(max14577_i2c_id) != MAXIM_DEVICE_TYPE_NUM);
546 	BUILD_BUG_ON(ARRAY_SIZE(max14577_dt_match) != MAXIM_DEVICE_TYPE_NUM);
547 
548 	/* Valid charger current values must be provided for each chipset */
549 	BUILD_BUG_ON(ARRAY_SIZE(maxim_charger_currents) != MAXIM_DEVICE_TYPE_NUM);
550 
551 	/* Check for valid values for charger */
552 	BUILD_BUG_ON(MAX14577_CHARGER_CURRENT_LIMIT_HIGH_START +
553 			MAX14577_CHARGER_CURRENT_LIMIT_HIGH_STEP * 0xf !=
554 			MAX14577_CHARGER_CURRENT_LIMIT_MAX);
555 	BUILD_BUG_ON(MAX14577_CHARGER_CURRENT_LIMIT_HIGH_STEP == 0);
556 
557 	BUILD_BUG_ON(MAX77836_CHARGER_CURRENT_LIMIT_HIGH_START +
558 			MAX77836_CHARGER_CURRENT_LIMIT_HIGH_STEP * 0xf !=
559 			MAX77836_CHARGER_CURRENT_LIMIT_MAX);
560 	BUILD_BUG_ON(MAX77836_CHARGER_CURRENT_LIMIT_HIGH_STEP == 0);
561 
562 	return i2c_add_driver(&max14577_i2c_driver);
563 }
564 subsys_initcall(max14577_i2c_init);
565 
566 static void __exit max14577_i2c_exit(void)
567 {
568 	i2c_del_driver(&max14577_i2c_driver);
569 }
570 module_exit(max14577_i2c_exit);
571 
572 MODULE_AUTHOR("Chanwoo Choi <cw00.choi@samsung.com>, Krzysztof Kozlowski <k.kozlowski@samsung.com>");
573 MODULE_DESCRIPTION("Maxim 14577/77836 multi-function core driver");
574 MODULE_LICENSE("GPL");
575