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/module.h>
13 #include <linux/interrupt.h>
14 #include <linux/of_device.h>
15 #include <linux/mfd/core.h>
16 #include <linux/mfd/max14577.h>
17 #include <linux/mfd/max14577-private.h>
18
19 /*
20 * Table of valid charger currents for different Maxim chipsets.
21 * It is placed here because it is used by both charger and regulator driver.
22 */
23 const struct maxim_charger_current maxim_charger_currents[] = {
24 [MAXIM_DEVICE_TYPE_UNKNOWN] = { 0, 0, 0, 0 },
25 [MAXIM_DEVICE_TYPE_MAX14577] = {
26 .min = MAX14577_CHARGER_CURRENT_LIMIT_MIN,
27 .high_start = MAX14577_CHARGER_CURRENT_LIMIT_HIGH_START,
28 .high_step = MAX14577_CHARGER_CURRENT_LIMIT_HIGH_STEP,
29 .max = MAX14577_CHARGER_CURRENT_LIMIT_MAX,
30 },
31 [MAXIM_DEVICE_TYPE_MAX77836] = {
32 .min = MAX77836_CHARGER_CURRENT_LIMIT_MIN,
33 .high_start = MAX77836_CHARGER_CURRENT_LIMIT_HIGH_START,
34 .high_step = MAX77836_CHARGER_CURRENT_LIMIT_HIGH_STEP,
35 .max = MAX77836_CHARGER_CURRENT_LIMIT_MAX,
36 },
37 };
38 EXPORT_SYMBOL_GPL(maxim_charger_currents);
39
40 /*
41 * maxim_charger_calc_reg_current - Calculate register value for current
42 * @limits: constraints for charger, matching the MBCICHWRC register
43 * @min_ua: minimal requested current, micro Amps
44 * @max_ua: maximum requested current, micro Amps
45 * @dst: destination to store calculated register value
46 *
47 * Calculates the value of MBCICHWRC (Fast Battery Charge Current) register
48 * for given current and stores it under pointed 'dst'. The stored value
49 * combines low bit (MBCICHWRCL) and high bits (MBCICHWRCH). It is also
50 * properly shifted.
51 *
52 * The calculated register value matches the current which:
53 * - is always between <limits.min, limits.max>;
54 * - is always less or equal to max_ua;
55 * - is the highest possible value;
56 * - may be lower than min_ua.
57 *
58 * On success returns 0. On error returns -EINVAL (requested min/max current
59 * is outside of given charger limits) and 'dst' is not set.
60 */
maxim_charger_calc_reg_current(const struct maxim_charger_current * limits,unsigned int min_ua,unsigned int max_ua,u8 * dst)61 int maxim_charger_calc_reg_current(const struct maxim_charger_current *limits,
62 unsigned int min_ua, unsigned int max_ua, u8 *dst)
63 {
64 unsigned int current_bits;
65
66 if (min_ua > max_ua)
67 return -EINVAL;
68
69 if (min_ua > limits->max || max_ua < limits->min)
70 return -EINVAL;
71
72 if (max_ua < limits->high_start) {
73 /*
74 * Less than high_start, so set the minimal current
75 * (turn Low Bit off, 0 as high bits).
76 */
77 *dst = 0x0;
78 return 0;
79 }
80
81 /* max_ua is in range: <high_start, infinite>, cut it to limits.max */
82 max_ua = min(limits->max, max_ua);
83 max_ua -= limits->high_start;
84 /*
85 * There is no risk of overflow 'max_ua' here because:
86 * - max_ua >= limits.high_start
87 * - BUILD_BUG checks that 'limits' are: max >= high_start + high_step
88 */
89 current_bits = max_ua / limits->high_step;
90
91 /* Turn Low Bit on (use range <limits.high_start, limits.max>) ... */
92 *dst = 0x1 << CHGCTRL4_MBCICHWRCL_SHIFT;
93 /* and set proper High Bits */
94 *dst |= current_bits << CHGCTRL4_MBCICHWRCH_SHIFT;
95
96 return 0;
97 }
98 EXPORT_SYMBOL_GPL(maxim_charger_calc_reg_current);
99
100 static const struct mfd_cell max14577_devs[] = {
101 {
102 .name = "max14577-muic",
103 .of_compatible = "maxim,max14577-muic",
104 },
105 {
106 .name = "max14577-regulator",
107 .of_compatible = "maxim,max14577-regulator",
108 },
109 {
110 .name = "max14577-charger",
111 .of_compatible = "maxim,max14577-charger",
112 },
113 };
114
115 static const struct mfd_cell max77836_devs[] = {
116 {
117 .name = "max77836-muic",
118 .of_compatible = "maxim,max77836-muic",
119 },
120 {
121 .name = "max77836-regulator",
122 .of_compatible = "maxim,max77836-regulator",
123 },
124 {
125 .name = "max77836-charger",
126 .of_compatible = "maxim,max77836-charger",
127 },
128 {
129 .name = "max77836-battery",
130 .of_compatible = "maxim,max77836-battery",
131 },
132 };
133
134 static const struct of_device_id max14577_dt_match[] = {
135 {
136 .compatible = "maxim,max14577",
137 .data = (void *)MAXIM_DEVICE_TYPE_MAX14577,
138 },
139 {
140 .compatible = "maxim,max77836",
141 .data = (void *)MAXIM_DEVICE_TYPE_MAX77836,
142 },
143 {},
144 };
145
max14577_muic_volatile_reg(struct device * dev,unsigned int reg)146 static bool max14577_muic_volatile_reg(struct device *dev, unsigned int reg)
147 {
148 switch (reg) {
149 case MAX14577_REG_INT1 ... MAX14577_REG_STATUS3:
150 return true;
151 default:
152 break;
153 }
154 return false;
155 }
156
max77836_muic_volatile_reg(struct device * dev,unsigned int reg)157 static bool max77836_muic_volatile_reg(struct device *dev, unsigned int reg)
158 {
159 /* Any max14577 volatile registers are also max77836 volatile. */
160 if (max14577_muic_volatile_reg(dev, reg))
161 return true;
162
163 switch (reg) {
164 case MAX77836_FG_REG_VCELL_MSB ... MAX77836_FG_REG_SOC_LSB:
165 case MAX77836_FG_REG_CRATE_MSB ... MAX77836_FG_REG_CRATE_LSB:
166 case MAX77836_FG_REG_STATUS_H ... MAX77836_FG_REG_STATUS_L:
167 case MAX77836_PMIC_REG_INTSRC:
168 case MAX77836_PMIC_REG_TOPSYS_INT:
169 case MAX77836_PMIC_REG_TOPSYS_STAT:
170 return true;
171 default:
172 break;
173 }
174 return false;
175 }
176
177 static const struct regmap_config max14577_muic_regmap_config = {
178 .reg_bits = 8,
179 .val_bits = 8,
180 .volatile_reg = max14577_muic_volatile_reg,
181 .max_register = MAX14577_REG_END,
182 };
183
184 static const struct regmap_config max77836_pmic_regmap_config = {
185 .reg_bits = 8,
186 .val_bits = 8,
187 .volatile_reg = max77836_muic_volatile_reg,
188 .max_register = MAX77836_PMIC_REG_END,
189 };
190
191 static const struct regmap_irq max14577_irqs[] = {
192 /* INT1 interrupts */
193 { .reg_offset = 0, .mask = MAX14577_INT1_ADC_MASK, },
194 { .reg_offset = 0, .mask = MAX14577_INT1_ADCLOW_MASK, },
195 { .reg_offset = 0, .mask = MAX14577_INT1_ADCERR_MASK, },
196 /* INT2 interrupts */
197 { .reg_offset = 1, .mask = MAX14577_INT2_CHGTYP_MASK, },
198 { .reg_offset = 1, .mask = MAX14577_INT2_CHGDETRUN_MASK, },
199 { .reg_offset = 1, .mask = MAX14577_INT2_DCDTMR_MASK, },
200 { .reg_offset = 1, .mask = MAX14577_INT2_DBCHG_MASK, },
201 { .reg_offset = 1, .mask = MAX14577_INT2_VBVOLT_MASK, },
202 /* INT3 interrupts */
203 { .reg_offset = 2, .mask = MAX14577_INT3_EOC_MASK, },
204 { .reg_offset = 2, .mask = MAX14577_INT3_CGMBC_MASK, },
205 { .reg_offset = 2, .mask = MAX14577_INT3_OVP_MASK, },
206 { .reg_offset = 2, .mask = MAX14577_INT3_MBCCHGERR_MASK, },
207 };
208
209 static const struct regmap_irq_chip max14577_irq_chip = {
210 .name = "max14577",
211 .status_base = MAX14577_REG_INT1,
212 .unmask_base = MAX14577_REG_INTMASK1,
213 .num_regs = 3,
214 .irqs = max14577_irqs,
215 .num_irqs = ARRAY_SIZE(max14577_irqs),
216 };
217
218 static const struct regmap_irq max77836_muic_irqs[] = {
219 /* INT1 interrupts */
220 { .reg_offset = 0, .mask = MAX14577_INT1_ADC_MASK, },
221 { .reg_offset = 0, .mask = MAX14577_INT1_ADCLOW_MASK, },
222 { .reg_offset = 0, .mask = MAX14577_INT1_ADCERR_MASK, },
223 { .reg_offset = 0, .mask = MAX77836_INT1_ADC1K_MASK, },
224 /* INT2 interrupts */
225 { .reg_offset = 1, .mask = MAX14577_INT2_CHGTYP_MASK, },
226 { .reg_offset = 1, .mask = MAX14577_INT2_CHGDETRUN_MASK, },
227 { .reg_offset = 1, .mask = MAX14577_INT2_DCDTMR_MASK, },
228 { .reg_offset = 1, .mask = MAX14577_INT2_DBCHG_MASK, },
229 { .reg_offset = 1, .mask = MAX14577_INT2_VBVOLT_MASK, },
230 { .reg_offset = 1, .mask = MAX77836_INT2_VIDRM_MASK, },
231 /* INT3 interrupts */
232 { .reg_offset = 2, .mask = MAX14577_INT3_EOC_MASK, },
233 { .reg_offset = 2, .mask = MAX14577_INT3_CGMBC_MASK, },
234 { .reg_offset = 2, .mask = MAX14577_INT3_OVP_MASK, },
235 { .reg_offset = 2, .mask = MAX14577_INT3_MBCCHGERR_MASK, },
236 };
237
238 static const struct regmap_irq_chip max77836_muic_irq_chip = {
239 .name = "max77836-muic",
240 .status_base = MAX14577_REG_INT1,
241 .unmask_base = MAX14577_REG_INTMASK1,
242 .num_regs = 3,
243 .irqs = max77836_muic_irqs,
244 .num_irqs = ARRAY_SIZE(max77836_muic_irqs),
245 };
246
247 static const struct regmap_irq max77836_pmic_irqs[] = {
248 { .reg_offset = 0, .mask = MAX77836_TOPSYS_INT_T120C_MASK, },
249 { .reg_offset = 0, .mask = MAX77836_TOPSYS_INT_T140C_MASK, },
250 };
251
252 static const struct regmap_irq_chip max77836_pmic_irq_chip = {
253 .name = "max77836-pmic",
254 .status_base = MAX77836_PMIC_REG_TOPSYS_INT,
255 .mask_base = MAX77836_PMIC_REG_TOPSYS_INT_MASK,
256 .num_regs = 1,
257 .irqs = max77836_pmic_irqs,
258 .num_irqs = ARRAY_SIZE(max77836_pmic_irqs),
259 };
260
max14577_print_dev_type(struct max14577 * max14577)261 static void max14577_print_dev_type(struct max14577 *max14577)
262 {
263 u8 reg_data, vendor_id, device_id;
264 int ret;
265
266 ret = max14577_read_reg(max14577->regmap, MAX14577_REG_DEVICEID,
267 ®_data);
268 if (ret) {
269 dev_err(max14577->dev,
270 "Failed to read DEVICEID register: %d\n", ret);
271 return;
272 }
273
274 vendor_id = ((reg_data & DEVID_VENDORID_MASK) >>
275 DEVID_VENDORID_SHIFT);
276 device_id = ((reg_data & DEVID_DEVICEID_MASK) >>
277 DEVID_DEVICEID_SHIFT);
278
279 dev_info(max14577->dev, "Device type: %u (ID: 0x%x, vendor: 0x%x)\n",
280 max14577->dev_type, device_id, vendor_id);
281 }
282
283 /*
284 * Max77836 specific initialization code for driver probe.
285 * Adds new I2C dummy device, regmap and regmap IRQ chip.
286 * Unmasks Interrupt Source register.
287 *
288 * On success returns 0.
289 * On failure returns errno and reverts any changes done so far (e.g. remove
290 * I2C dummy device), except masking the INT SRC register.
291 */
max77836_init(struct max14577 * max14577)292 static int max77836_init(struct max14577 *max14577)
293 {
294 int ret;
295 u8 intsrc_mask;
296
297 max14577->i2c_pmic = i2c_new_dummy_device(max14577->i2c->adapter,
298 I2C_ADDR_PMIC);
299 if (IS_ERR(max14577->i2c_pmic)) {
300 dev_err(max14577->dev, "Failed to register PMIC I2C device\n");
301 return PTR_ERR(max14577->i2c_pmic);
302 }
303 i2c_set_clientdata(max14577->i2c_pmic, max14577);
304
305 max14577->regmap_pmic = devm_regmap_init_i2c(max14577->i2c_pmic,
306 &max77836_pmic_regmap_config);
307 if (IS_ERR(max14577->regmap_pmic)) {
308 ret = PTR_ERR(max14577->regmap_pmic);
309 dev_err(max14577->dev, "Failed to allocate PMIC register map: %d\n",
310 ret);
311 goto err;
312 }
313
314 /* Un-mask MAX77836 Interrupt Source register */
315 ret = max14577_read_reg(max14577->regmap_pmic,
316 MAX77836_PMIC_REG_INTSRC_MASK, &intsrc_mask);
317 if (ret < 0) {
318 dev_err(max14577->dev, "Failed to read PMIC register\n");
319 goto err;
320 }
321
322 intsrc_mask &= ~(MAX77836_INTSRC_MASK_TOP_INT_MASK);
323 intsrc_mask &= ~(MAX77836_INTSRC_MASK_MUIC_CHG_INT_MASK);
324 ret = max14577_write_reg(max14577->regmap_pmic,
325 MAX77836_PMIC_REG_INTSRC_MASK, intsrc_mask);
326 if (ret < 0) {
327 dev_err(max14577->dev, "Failed to write PMIC register\n");
328 goto err;
329 }
330
331 ret = regmap_add_irq_chip(max14577->regmap_pmic, max14577->irq,
332 IRQF_ONESHOT | IRQF_SHARED,
333 0, &max77836_pmic_irq_chip,
334 &max14577->irq_data_pmic);
335 if (ret != 0) {
336 dev_err(max14577->dev, "Failed to request PMIC IRQ %d: %d\n",
337 max14577->irq, ret);
338 goto err;
339 }
340
341 return 0;
342
343 err:
344 i2c_unregister_device(max14577->i2c_pmic);
345
346 return ret;
347 }
348
349 /*
350 * Max77836 specific de-initialization code for driver remove.
351 */
max77836_remove(struct max14577 * max14577)352 static void max77836_remove(struct max14577 *max14577)
353 {
354 regmap_del_irq_chip(max14577->irq, max14577->irq_data_pmic);
355 i2c_unregister_device(max14577->i2c_pmic);
356 }
357
max14577_i2c_probe(struct i2c_client * i2c)358 static int max14577_i2c_probe(struct i2c_client *i2c)
359 {
360 const struct i2c_device_id *id = i2c_client_get_device_id(i2c);
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 if (np) {
401 const struct of_device_id *of_id;
402
403 of_id = of_match_device(max14577_dt_match, &i2c->dev);
404 if (of_id)
405 max14577->dev_type = (uintptr_t)of_id->data;
406 } else {
407 max14577->dev_type = id->driver_data;
408 }
409
410 max14577_print_dev_type(max14577);
411
412 switch (max14577->dev_type) {
413 case MAXIM_DEVICE_TYPE_MAX77836:
414 irq_chip = &max77836_muic_irq_chip;
415 mfd_devs = max77836_devs;
416 mfd_devs_size = ARRAY_SIZE(max77836_devs);
417 irq_flags = IRQF_ONESHOT | IRQF_SHARED;
418 break;
419 case MAXIM_DEVICE_TYPE_MAX14577:
420 default:
421 irq_chip = &max14577_irq_chip;
422 mfd_devs = max14577_devs;
423 mfd_devs_size = ARRAY_SIZE(max14577_devs);
424 irq_flags = IRQF_ONESHOT;
425 break;
426 }
427
428 ret = regmap_add_irq_chip(max14577->regmap, max14577->irq,
429 irq_flags, 0, irq_chip,
430 &max14577->irq_data);
431 if (ret != 0) {
432 dev_err(&i2c->dev, "Failed to request IRQ %d: %d\n",
433 max14577->irq, ret);
434 return ret;
435 }
436
437 /* Max77836 specific initialization code (additional regmap) */
438 if (max14577->dev_type == MAXIM_DEVICE_TYPE_MAX77836) {
439 ret = max77836_init(max14577);
440 if (ret < 0)
441 goto err_max77836;
442 }
443
444 ret = mfd_add_devices(max14577->dev, -1, mfd_devs,
445 mfd_devs_size, NULL, 0, NULL);
446 if (ret < 0)
447 goto err_mfd;
448
449 device_init_wakeup(max14577->dev, 1);
450
451 return 0;
452
453 err_mfd:
454 if (max14577->dev_type == MAXIM_DEVICE_TYPE_MAX77836)
455 max77836_remove(max14577);
456 err_max77836:
457 regmap_del_irq_chip(max14577->irq, max14577->irq_data);
458
459 return ret;
460 }
461
max14577_i2c_remove(struct i2c_client * i2c)462 static void max14577_i2c_remove(struct i2c_client *i2c)
463 {
464 struct max14577 *max14577 = i2c_get_clientdata(i2c);
465
466 mfd_remove_devices(max14577->dev);
467 regmap_del_irq_chip(max14577->irq, max14577->irq_data);
468 if (max14577->dev_type == MAXIM_DEVICE_TYPE_MAX77836)
469 max77836_remove(max14577);
470 }
471
472 static const struct i2c_device_id max14577_i2c_id[] = {
473 { "max14577", MAXIM_DEVICE_TYPE_MAX14577, },
474 { "max77836", MAXIM_DEVICE_TYPE_MAX77836, },
475 { }
476 };
477 MODULE_DEVICE_TABLE(i2c, max14577_i2c_id);
478
max14577_suspend(struct device * dev)479 static int max14577_suspend(struct device *dev)
480 {
481 struct i2c_client *i2c = to_i2c_client(dev);
482 struct max14577 *max14577 = i2c_get_clientdata(i2c);
483
484 if (device_may_wakeup(dev))
485 enable_irq_wake(max14577->irq);
486 /*
487 * MUIC IRQ must be disabled during suspend because if it happens
488 * while suspended it will be handled before resuming I2C.
489 *
490 * When device is woken up from suspend (e.g. by ADC change),
491 * an interrupt occurs before resuming I2C bus controller.
492 * Interrupt handler tries to read registers but this read
493 * will fail because I2C is still suspended.
494 */
495 disable_irq(max14577->irq);
496
497 return 0;
498 }
499
max14577_resume(struct device * dev)500 static int max14577_resume(struct device *dev)
501 {
502 struct i2c_client *i2c = to_i2c_client(dev);
503 struct max14577 *max14577 = i2c_get_clientdata(i2c);
504
505 if (device_may_wakeup(dev))
506 disable_irq_wake(max14577->irq);
507 enable_irq(max14577->irq);
508
509 return 0;
510 }
511
512 static DEFINE_SIMPLE_DEV_PM_OPS(max14577_pm, max14577_suspend, max14577_resume);
513
514 static struct i2c_driver max14577_i2c_driver = {
515 .driver = {
516 .name = "max14577",
517 .pm = pm_sleep_ptr(&max14577_pm),
518 .of_match_table = max14577_dt_match,
519 },
520 .probe = max14577_i2c_probe,
521 .remove = max14577_i2c_remove,
522 .id_table = max14577_i2c_id,
523 };
524
max14577_i2c_init(void)525 static int __init max14577_i2c_init(void)
526 {
527 BUILD_BUG_ON(ARRAY_SIZE(max14577_i2c_id) != MAXIM_DEVICE_TYPE_NUM);
528 BUILD_BUG_ON(ARRAY_SIZE(max14577_dt_match) != MAXIM_DEVICE_TYPE_NUM);
529
530 /* Valid charger current values must be provided for each chipset */
531 BUILD_BUG_ON(ARRAY_SIZE(maxim_charger_currents) != MAXIM_DEVICE_TYPE_NUM);
532
533 /* Check for valid values for charger */
534 BUILD_BUG_ON(MAX14577_CHARGER_CURRENT_LIMIT_HIGH_START +
535 MAX14577_CHARGER_CURRENT_LIMIT_HIGH_STEP * 0xf !=
536 MAX14577_CHARGER_CURRENT_LIMIT_MAX);
537 BUILD_BUG_ON(MAX14577_CHARGER_CURRENT_LIMIT_HIGH_STEP == 0);
538
539 BUILD_BUG_ON(MAX77836_CHARGER_CURRENT_LIMIT_HIGH_START +
540 MAX77836_CHARGER_CURRENT_LIMIT_HIGH_STEP * 0xf !=
541 MAX77836_CHARGER_CURRENT_LIMIT_MAX);
542 BUILD_BUG_ON(MAX77836_CHARGER_CURRENT_LIMIT_HIGH_STEP == 0);
543
544 return i2c_add_driver(&max14577_i2c_driver);
545 }
546 module_init(max14577_i2c_init);
547
max14577_i2c_exit(void)548 static void __exit max14577_i2c_exit(void)
549 {
550 i2c_del_driver(&max14577_i2c_driver);
551 }
552 module_exit(max14577_i2c_exit);
553
554 MODULE_AUTHOR("Chanwoo Choi <cw00.choi@samsung.com>, Krzysztof Kozlowski <krzk@kernel.org>");
555 MODULE_DESCRIPTION("Maxim 14577/77836 multi-function core driver");
556 MODULE_LICENSE("GPL");
557