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 */
33const 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};
48EXPORT_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 */
71int 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}
108EXPORT_SYMBOL_GPL(maxim_charger_calc_reg_current);
109
110static 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
125static 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
144static 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
156static 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
167static 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
187static 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
194static 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
201static 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
219static 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
229static 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
249static 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
259static 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
264static 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
274static 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 */
305static 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
356err:
357	i2c_unregister_device(max14577->i2c_pmic);
358
359	return ret;
360}
361
362/*
363 * Max77836 specific de-initialization code for driver remove.
364 */
365static 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
371static 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
467err_mfd:
468	if (max14577->dev_type == MAXIM_DEVICE_TYPE_MAX77836)
469		max77836_remove(max14577);
470err_max77836:
471	regmap_del_irq_chip(max14577->irq, max14577->irq_data);
472
473	return ret;
474}
475
476static 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
488static const struct i2c_device_id max14577_i2c_id[] = {
489	{ "max14577", MAXIM_DEVICE_TYPE_MAX14577, },
490	{ "max77836", MAXIM_DEVICE_TYPE_MAX77836, },
491	{ }
492};
493MODULE_DEVICE_TABLE(i2c, max14577_i2c_id);
494
495#ifdef CONFIG_PM_SLEEP
496static 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
517static 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
530static SIMPLE_DEV_PM_OPS(max14577_pm, max14577_suspend, max14577_resume);
531
532static 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
543static 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}
564subsys_initcall(max14577_i2c_init);
565
566static void __exit max14577_i2c_exit(void)
567{
568	i2c_del_driver(&max14577_i2c_driver);
569}
570module_exit(max14577_i2c_exit);
571
572MODULE_AUTHOR("Chanwoo Choi <cw00.choi@samsung.com>, Krzysztof Kozlowski <k.kozlowski@samsung.com>");
573MODULE_DESCRIPTION("Maxim 14577/77836 multi-function core driver");
574MODULE_LICENSE("GPL");
575