1// SPDX-License-Identifier: GPL-2.0+
2//
3// max14577.c - mfd core driver for the Maxim 14577/77836
4//
5// Copyright (C) 2014 Samsung Electronics
6// Chanwoo Choi <cw00.choi@samsung.com>
7// Krzysztof Kozlowski <krzk@kernel.org>
8//
9// This driver is based on max8997.c
10
11#include <linux/err.h>
12#include <linux/i2c.h>
13#include <linux/mod_devicetable.h>
14#include <linux/module.h>
15#include <linux/interrupt.h>
16#include <linux/mfd/core.h>
17#include <linux/mfd/max14577.h>
18#include <linux/mfd/max14577-private.h>
19
20/*
21 * Table of valid charger currents for different Maxim chipsets.
22 * It is placed here because it is used by both charger and regulator driver.
23 */
24const struct maxim_charger_current maxim_charger_currents[] = {
25	[MAXIM_DEVICE_TYPE_UNKNOWN] = { 0, 0, 0, 0 },
26	[MAXIM_DEVICE_TYPE_MAX14577] = {
27		.min		= MAX14577_CHARGER_CURRENT_LIMIT_MIN,
28		.high_start	= MAX14577_CHARGER_CURRENT_LIMIT_HIGH_START,
29		.high_step	= MAX14577_CHARGER_CURRENT_LIMIT_HIGH_STEP,
30		.max		= MAX14577_CHARGER_CURRENT_LIMIT_MAX,
31	},
32	[MAXIM_DEVICE_TYPE_MAX77836] = {
33		.min		= MAX77836_CHARGER_CURRENT_LIMIT_MIN,
34		.high_start	= MAX77836_CHARGER_CURRENT_LIMIT_HIGH_START,
35		.high_step	= MAX77836_CHARGER_CURRENT_LIMIT_HIGH_STEP,
36		.max		= MAX77836_CHARGER_CURRENT_LIMIT_MAX,
37	},
38};
39EXPORT_SYMBOL_GPL(maxim_charger_currents);
40
41/*
42 * maxim_charger_calc_reg_current - Calculate register value for current
43 * @limits:	constraints for charger, matching the MBCICHWRC register
44 * @min_ua:	minimal requested current, micro Amps
45 * @max_ua:	maximum requested current, micro Amps
46 * @dst:	destination to store calculated register value
47 *
48 * Calculates the value of MBCICHWRC (Fast Battery Charge Current) register
49 * for given current and stores it under pointed 'dst'. The stored value
50 * combines low bit (MBCICHWRCL) and high bits (MBCICHWRCH). It is also
51 * properly shifted.
52 *
53 * The calculated register value matches the current which:
54 *  - is always between <limits.min, limits.max>;
55 *  - is always less or equal to max_ua;
56 *  - is the highest possible value;
57 *  - may be lower than min_ua.
58 *
59 * On success returns 0. On error returns -EINVAL (requested min/max current
60 * is outside of given charger limits) and 'dst' is not set.
61 */
62int maxim_charger_calc_reg_current(const struct maxim_charger_current *limits,
63		unsigned int min_ua, unsigned int max_ua, u8 *dst)
64{
65	unsigned int current_bits;
66
67	if (min_ua > max_ua)
68		return -EINVAL;
69
70	if (min_ua > limits->max || max_ua < limits->min)
71		return -EINVAL;
72
73	if (max_ua < limits->high_start) {
74		/*
75		 * Less than high_start, so set the minimal current
76		 * (turn Low Bit off, 0 as high bits).
77		 */
78		*dst = 0x0;
79		return 0;
80	}
81
82	/* max_ua is in range: <high_start, infinite>, cut it to limits.max */
83	max_ua = min(limits->max, max_ua);
84	max_ua -= limits->high_start;
85	/*
86	 * There is no risk of overflow 'max_ua' here because:
87	 *  - max_ua >= limits.high_start
88	 *  - BUILD_BUG checks that 'limits' are: max >= high_start + high_step
89	 */
90	current_bits = max_ua / limits->high_step;
91
92	/* Turn Low Bit on (use range <limits.high_start, limits.max>) ... */
93	*dst = 0x1 << CHGCTRL4_MBCICHWRCL_SHIFT;
94	/* and set proper High Bits */
95	*dst |= current_bits << CHGCTRL4_MBCICHWRCH_SHIFT;
96
97	return 0;
98}
99EXPORT_SYMBOL_GPL(maxim_charger_calc_reg_current);
100
101static const struct mfd_cell max14577_devs[] = {
102	{
103		.name = "max14577-muic",
104		.of_compatible = "maxim,max14577-muic",
105	},
106	{
107		.name = "max14577-regulator",
108		.of_compatible = "maxim,max14577-regulator",
109	},
110	{
111		.name = "max14577-charger",
112		.of_compatible = "maxim,max14577-charger",
113	},
114};
115
116static const struct mfd_cell max77836_devs[] = {
117	{
118		.name = "max77836-muic",
119		.of_compatible = "maxim,max77836-muic",
120	},
121	{
122		.name = "max77836-regulator",
123		.of_compatible = "maxim,max77836-regulator",
124	},
125	{
126		.name = "max77836-charger",
127		.of_compatible = "maxim,max77836-charger",
128	},
129	{
130		.name = "max77836-battery",
131		.of_compatible = "maxim,max77836-battery",
132	},
133};
134
135static const struct of_device_id max14577_dt_match[] = {
136	{
137		.compatible = "maxim,max14577",
138		.data = (void *)MAXIM_DEVICE_TYPE_MAX14577,
139	},
140	{
141		.compatible = "maxim,max77836",
142		.data = (void *)MAXIM_DEVICE_TYPE_MAX77836,
143	},
144	{},
145};
146
147static bool max14577_muic_volatile_reg(struct device *dev, unsigned int reg)
148{
149	switch (reg) {
150	case MAX14577_REG_INT1 ... MAX14577_REG_STATUS3:
151		return true;
152	default:
153		break;
154	}
155	return false;
156}
157
158static bool max77836_muic_volatile_reg(struct device *dev, unsigned int reg)
159{
160	/* Any max14577 volatile registers are also max77836 volatile. */
161	if (max14577_muic_volatile_reg(dev, reg))
162		return true;
163
164	switch (reg) {
165	case MAX77836_FG_REG_VCELL_MSB ... MAX77836_FG_REG_SOC_LSB:
166	case MAX77836_FG_REG_CRATE_MSB ... MAX77836_FG_REG_CRATE_LSB:
167	case MAX77836_FG_REG_STATUS_H ... MAX77836_FG_REG_STATUS_L:
168	case MAX77836_PMIC_REG_INTSRC:
169	case MAX77836_PMIC_REG_TOPSYS_INT:
170	case MAX77836_PMIC_REG_TOPSYS_STAT:
171		return true;
172	default:
173		break;
174	}
175	return false;
176}
177
178static const struct regmap_config max14577_muic_regmap_config = {
179	.reg_bits	= 8,
180	.val_bits	= 8,
181	.volatile_reg	= max14577_muic_volatile_reg,
182	.max_register	= MAX14577_REG_END,
183};
184
185static const struct regmap_config max77836_pmic_regmap_config = {
186	.reg_bits	= 8,
187	.val_bits	= 8,
188	.volatile_reg	= max77836_muic_volatile_reg,
189	.max_register	= MAX77836_PMIC_REG_END,
190};
191
192static const struct regmap_irq max14577_irqs[] = {
193	/* INT1 interrupts */
194	{ .reg_offset = 0, .mask = MAX14577_INT1_ADC_MASK, },
195	{ .reg_offset = 0, .mask = MAX14577_INT1_ADCLOW_MASK, },
196	{ .reg_offset = 0, .mask = MAX14577_INT1_ADCERR_MASK, },
197	/* INT2 interrupts */
198	{ .reg_offset = 1, .mask = MAX14577_INT2_CHGTYP_MASK, },
199	{ .reg_offset = 1, .mask = MAX14577_INT2_CHGDETRUN_MASK, },
200	{ .reg_offset = 1, .mask = MAX14577_INT2_DCDTMR_MASK, },
201	{ .reg_offset = 1, .mask = MAX14577_INT2_DBCHG_MASK, },
202	{ .reg_offset = 1, .mask = MAX14577_INT2_VBVOLT_MASK, },
203	/* INT3 interrupts */
204	{ .reg_offset = 2, .mask = MAX14577_INT3_EOC_MASK, },
205	{ .reg_offset = 2, .mask = MAX14577_INT3_CGMBC_MASK, },
206	{ .reg_offset = 2, .mask = MAX14577_INT3_OVP_MASK, },
207	{ .reg_offset = 2, .mask = MAX14577_INT3_MBCCHGERR_MASK, },
208};
209
210static const struct regmap_irq_chip max14577_irq_chip = {
211	.name			= "max14577",
212	.status_base		= MAX14577_REG_INT1,
213	.unmask_base		= MAX14577_REG_INTMASK1,
214	.num_regs		= 3,
215	.irqs			= max14577_irqs,
216	.num_irqs		= ARRAY_SIZE(max14577_irqs),
217};
218
219static const struct regmap_irq max77836_muic_irqs[] = {
220	/* INT1 interrupts */
221	{ .reg_offset = 0, .mask = MAX14577_INT1_ADC_MASK, },
222	{ .reg_offset = 0, .mask = MAX14577_INT1_ADCLOW_MASK, },
223	{ .reg_offset = 0, .mask = MAX14577_INT1_ADCERR_MASK, },
224	{ .reg_offset = 0, .mask = MAX77836_INT1_ADC1K_MASK, },
225	/* INT2 interrupts */
226	{ .reg_offset = 1, .mask = MAX14577_INT2_CHGTYP_MASK, },
227	{ .reg_offset = 1, .mask = MAX14577_INT2_CHGDETRUN_MASK, },
228	{ .reg_offset = 1, .mask = MAX14577_INT2_DCDTMR_MASK, },
229	{ .reg_offset = 1, .mask = MAX14577_INT2_DBCHG_MASK, },
230	{ .reg_offset = 1, .mask = MAX14577_INT2_VBVOLT_MASK, },
231	{ .reg_offset = 1, .mask = MAX77836_INT2_VIDRM_MASK, },
232	/* INT3 interrupts */
233	{ .reg_offset = 2, .mask = MAX14577_INT3_EOC_MASK, },
234	{ .reg_offset = 2, .mask = MAX14577_INT3_CGMBC_MASK, },
235	{ .reg_offset = 2, .mask = MAX14577_INT3_OVP_MASK, },
236	{ .reg_offset = 2, .mask = MAX14577_INT3_MBCCHGERR_MASK, },
237};
238
239static const struct regmap_irq_chip max77836_muic_irq_chip = {
240	.name			= "max77836-muic",
241	.status_base		= MAX14577_REG_INT1,
242	.unmask_base		= MAX14577_REG_INTMASK1,
243	.num_regs		= 3,
244	.irqs			= max77836_muic_irqs,
245	.num_irqs		= ARRAY_SIZE(max77836_muic_irqs),
246};
247
248static const struct regmap_irq max77836_pmic_irqs[] = {
249	{ .reg_offset = 0, .mask = MAX77836_TOPSYS_INT_T120C_MASK, },
250	{ .reg_offset = 0, .mask = MAX77836_TOPSYS_INT_T140C_MASK, },
251};
252
253static const struct regmap_irq_chip max77836_pmic_irq_chip = {
254	.name			= "max77836-pmic",
255	.status_base		= MAX77836_PMIC_REG_TOPSYS_INT,
256	.mask_base		= MAX77836_PMIC_REG_TOPSYS_INT_MASK,
257	.num_regs		= 1,
258	.irqs			= max77836_pmic_irqs,
259	.num_irqs		= ARRAY_SIZE(max77836_pmic_irqs),
260};
261
262static void max14577_print_dev_type(struct max14577 *max14577)
263{
264	u8 reg_data, vendor_id, device_id;
265	int ret;
266
267	ret = max14577_read_reg(max14577->regmap, MAX14577_REG_DEVICEID,
268			&reg_data);
269	if (ret) {
270		dev_err(max14577->dev,
271			"Failed to read DEVICEID register: %d\n", ret);
272		return;
273	}
274
275	vendor_id = ((reg_data & DEVID_VENDORID_MASK) >>
276				DEVID_VENDORID_SHIFT);
277	device_id = ((reg_data & DEVID_DEVICEID_MASK) >>
278				DEVID_DEVICEID_SHIFT);
279
280	dev_info(max14577->dev, "Device type: %u (ID: 0x%x, vendor: 0x%x)\n",
281			max14577->dev_type, device_id, vendor_id);
282}
283
284/*
285 * Max77836 specific initialization code for driver probe.
286 * Adds new I2C dummy device, regmap and regmap IRQ chip.
287 * Unmasks Interrupt Source register.
288 *
289 * On success returns 0.
290 * On failure returns errno and reverts any changes done so far (e.g. remove
291 * I2C dummy device), except masking the INT SRC register.
292 */
293static int max77836_init(struct max14577 *max14577)
294{
295	int ret;
296	u8 intsrc_mask;
297
298	max14577->i2c_pmic = i2c_new_dummy_device(max14577->i2c->adapter,
299			I2C_ADDR_PMIC);
300	if (IS_ERR(max14577->i2c_pmic)) {
301		dev_err(max14577->dev, "Failed to register PMIC I2C device\n");
302		return PTR_ERR(max14577->i2c_pmic);
303	}
304	i2c_set_clientdata(max14577->i2c_pmic, max14577);
305
306	max14577->regmap_pmic = devm_regmap_init_i2c(max14577->i2c_pmic,
307			&max77836_pmic_regmap_config);
308	if (IS_ERR(max14577->regmap_pmic)) {
309		ret = PTR_ERR(max14577->regmap_pmic);
310		dev_err(max14577->dev, "Failed to allocate PMIC register map: %d\n",
311				ret);
312		goto err;
313	}
314
315	/* Un-mask MAX77836 Interrupt Source register */
316	ret = max14577_read_reg(max14577->regmap_pmic,
317			MAX77836_PMIC_REG_INTSRC_MASK, &intsrc_mask);
318	if (ret < 0) {
319		dev_err(max14577->dev, "Failed to read PMIC register\n");
320		goto err;
321	}
322
323	intsrc_mask &= ~(MAX77836_INTSRC_MASK_TOP_INT_MASK);
324	intsrc_mask &= ~(MAX77836_INTSRC_MASK_MUIC_CHG_INT_MASK);
325	ret = max14577_write_reg(max14577->regmap_pmic,
326			MAX77836_PMIC_REG_INTSRC_MASK, intsrc_mask);
327	if (ret < 0) {
328		dev_err(max14577->dev, "Failed to write PMIC register\n");
329		goto err;
330	}
331
332	ret = regmap_add_irq_chip(max14577->regmap_pmic, max14577->irq,
333			IRQF_ONESHOT | IRQF_SHARED,
334			0, &max77836_pmic_irq_chip,
335			&max14577->irq_data_pmic);
336	if (ret != 0) {
337		dev_err(max14577->dev, "Failed to request PMIC IRQ %d: %d\n",
338				max14577->irq, ret);
339		goto err;
340	}
341
342	return 0;
343
344err:
345	i2c_unregister_device(max14577->i2c_pmic);
346
347	return ret;
348}
349
350/*
351 * Max77836 specific de-initialization code for driver remove.
352 */
353static void max77836_remove(struct max14577 *max14577)
354{
355	regmap_del_irq_chip(max14577->irq, max14577->irq_data_pmic);
356	i2c_unregister_device(max14577->i2c_pmic);
357}
358
359static int max14577_i2c_probe(struct i2c_client *i2c)
360{
361	struct max14577 *max14577;
362	struct max14577_platform_data *pdata = dev_get_platdata(&i2c->dev);
363	struct device_node *np = i2c->dev.of_node;
364	int ret = 0;
365	const struct regmap_irq_chip *irq_chip;
366	const struct mfd_cell *mfd_devs;
367	unsigned int mfd_devs_size;
368	int irq_flags;
369
370	if (np) {
371		pdata = devm_kzalloc(&i2c->dev, sizeof(*pdata), GFP_KERNEL);
372		if (!pdata)
373			return -ENOMEM;
374		i2c->dev.platform_data = pdata;
375	}
376
377	if (!pdata) {
378		dev_err(&i2c->dev, "No platform data found.\n");
379		return -EINVAL;
380	}
381
382	max14577 = devm_kzalloc(&i2c->dev, sizeof(*max14577), GFP_KERNEL);
383	if (!max14577)
384		return -ENOMEM;
385
386	i2c_set_clientdata(i2c, max14577);
387	max14577->dev = &i2c->dev;
388	max14577->i2c = i2c;
389	max14577->irq = i2c->irq;
390
391	max14577->regmap = devm_regmap_init_i2c(i2c,
392			&max14577_muic_regmap_config);
393	if (IS_ERR(max14577->regmap)) {
394		ret = PTR_ERR(max14577->regmap);
395		dev_err(max14577->dev, "Failed to allocate register map: %d\n",
396				ret);
397		return ret;
398	}
399
400	max14577->dev_type = (enum maxim_device_type)i2c_get_match_data(i2c);
401
402	max14577_print_dev_type(max14577);
403
404	switch (max14577->dev_type) {
405	case MAXIM_DEVICE_TYPE_MAX77836:
406		irq_chip = &max77836_muic_irq_chip;
407		mfd_devs = max77836_devs;
408		mfd_devs_size = ARRAY_SIZE(max77836_devs);
409		irq_flags = IRQF_ONESHOT | IRQF_SHARED;
410		break;
411	case MAXIM_DEVICE_TYPE_MAX14577:
412	default:
413		irq_chip = &max14577_irq_chip;
414		mfd_devs = max14577_devs;
415		mfd_devs_size = ARRAY_SIZE(max14577_devs);
416		irq_flags = IRQF_ONESHOT;
417		break;
418	}
419
420	ret = regmap_add_irq_chip(max14577->regmap, max14577->irq,
421				  irq_flags, 0, irq_chip,
422				  &max14577->irq_data);
423	if (ret != 0) {
424		dev_err(&i2c->dev, "Failed to request IRQ %d: %d\n",
425				max14577->irq, ret);
426		return ret;
427	}
428
429	/* Max77836 specific initialization code (additional regmap) */
430	if (max14577->dev_type == MAXIM_DEVICE_TYPE_MAX77836) {
431		ret = max77836_init(max14577);
432		if (ret < 0)
433			goto err_max77836;
434	}
435
436	ret = mfd_add_devices(max14577->dev, -1, mfd_devs,
437			mfd_devs_size, NULL, 0, NULL);
438	if (ret < 0)
439		goto err_mfd;
440
441	device_init_wakeup(max14577->dev, 1);
442
443	return 0;
444
445err_mfd:
446	if (max14577->dev_type == MAXIM_DEVICE_TYPE_MAX77836)
447		max77836_remove(max14577);
448err_max77836:
449	regmap_del_irq_chip(max14577->irq, max14577->irq_data);
450
451	return ret;
452}
453
454static void max14577_i2c_remove(struct i2c_client *i2c)
455{
456	struct max14577 *max14577 = i2c_get_clientdata(i2c);
457
458	mfd_remove_devices(max14577->dev);
459	regmap_del_irq_chip(max14577->irq, max14577->irq_data);
460	if (max14577->dev_type == MAXIM_DEVICE_TYPE_MAX77836)
461		max77836_remove(max14577);
462}
463
464static const struct i2c_device_id max14577_i2c_id[] = {
465	{ "max14577", MAXIM_DEVICE_TYPE_MAX14577, },
466	{ "max77836", MAXIM_DEVICE_TYPE_MAX77836, },
467	{ }
468};
469MODULE_DEVICE_TABLE(i2c, max14577_i2c_id);
470
471static int max14577_suspend(struct device *dev)
472{
473	struct i2c_client *i2c = to_i2c_client(dev);
474	struct max14577 *max14577 = i2c_get_clientdata(i2c);
475
476	if (device_may_wakeup(dev))
477		enable_irq_wake(max14577->irq);
478	/*
479	 * MUIC IRQ must be disabled during suspend because if it happens
480	 * while suspended it will be handled before resuming I2C.
481	 *
482	 * When device is woken up from suspend (e.g. by ADC change),
483	 * an interrupt occurs before resuming I2C bus controller.
484	 * Interrupt handler tries to read registers but this read
485	 * will fail because I2C is still suspended.
486	 */
487	disable_irq(max14577->irq);
488
489	return 0;
490}
491
492static int max14577_resume(struct device *dev)
493{
494	struct i2c_client *i2c = to_i2c_client(dev);
495	struct max14577 *max14577 = i2c_get_clientdata(i2c);
496
497	if (device_may_wakeup(dev))
498		disable_irq_wake(max14577->irq);
499	enable_irq(max14577->irq);
500
501	return 0;
502}
503
504static DEFINE_SIMPLE_DEV_PM_OPS(max14577_pm, max14577_suspend, max14577_resume);
505
506static struct i2c_driver max14577_i2c_driver = {
507	.driver = {
508		.name = "max14577",
509		.pm = pm_sleep_ptr(&max14577_pm),
510		.of_match_table = max14577_dt_match,
511	},
512	.probe = max14577_i2c_probe,
513	.remove = max14577_i2c_remove,
514	.id_table = max14577_i2c_id,
515};
516
517static int __init max14577_i2c_init(void)
518{
519	BUILD_BUG_ON(ARRAY_SIZE(max14577_i2c_id) != MAXIM_DEVICE_TYPE_NUM);
520	BUILD_BUG_ON(ARRAY_SIZE(max14577_dt_match) != MAXIM_DEVICE_TYPE_NUM);
521
522	/* Valid charger current values must be provided for each chipset */
523	BUILD_BUG_ON(ARRAY_SIZE(maxim_charger_currents) != MAXIM_DEVICE_TYPE_NUM);
524
525	/* Check for valid values for charger */
526	BUILD_BUG_ON(MAX14577_CHARGER_CURRENT_LIMIT_HIGH_START +
527			MAX14577_CHARGER_CURRENT_LIMIT_HIGH_STEP * 0xf !=
528			MAX14577_CHARGER_CURRENT_LIMIT_MAX);
529	BUILD_BUG_ON(MAX14577_CHARGER_CURRENT_LIMIT_HIGH_STEP == 0);
530
531	BUILD_BUG_ON(MAX77836_CHARGER_CURRENT_LIMIT_HIGH_START +
532			MAX77836_CHARGER_CURRENT_LIMIT_HIGH_STEP * 0xf !=
533			MAX77836_CHARGER_CURRENT_LIMIT_MAX);
534	BUILD_BUG_ON(MAX77836_CHARGER_CURRENT_LIMIT_HIGH_STEP == 0);
535
536	return i2c_add_driver(&max14577_i2c_driver);
537}
538module_init(max14577_i2c_init);
539
540static void __exit max14577_i2c_exit(void)
541{
542	i2c_del_driver(&max14577_i2c_driver);
543}
544module_exit(max14577_i2c_exit);
545
546MODULE_AUTHOR("Chanwoo Choi <cw00.choi@samsung.com>, Krzysztof Kozlowski <krzk@kernel.org>");
547MODULE_DESCRIPTION("Maxim 14577/77836 multi-function core driver");
548MODULE_LICENSE("GPL");
549