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/module.h>
14 #include <linux/interrupt.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 MODULE_DEVICE_TABLE(of, max14577_dt_match);
146
max14577_muic_volatile_reg(struct device * dev,unsigned int reg)147 static 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
max77836_muic_volatile_reg(struct device * dev,unsigned int reg)158 static 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
178 static 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
185 static 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
192 static 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
210 static 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
219 static 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
239 static 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
248 static 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
253 static 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
max14577_print_dev_type(struct max14577 * max14577)262 static 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 ®_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 */
max77836_init(struct max14577 * max14577)293 static 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
344 err:
345 i2c_unregister_device(max14577->i2c_pmic);
346
347 return ret;
348 }
349
350 /*
351 * Max77836 specific de-initialization code for driver remove.
352 */
max77836_remove(struct max14577 * max14577)353 static 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
max14577_i2c_probe(struct i2c_client * i2c)359 static 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 = (kernel_ulong_t)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
445 err_mfd:
446 if (max14577->dev_type == MAXIM_DEVICE_TYPE_MAX77836)
447 max77836_remove(max14577);
448 err_max77836:
449 regmap_del_irq_chip(max14577->irq, max14577->irq_data);
450
451 return ret;
452 }
453
max14577_i2c_remove(struct i2c_client * i2c)454 static void max14577_i2c_remove(struct i2c_client *i2c)
455 {
456 struct max14577 *max14577 = i2c_get_clientdata(i2c);
457
458 device_init_wakeup(max14577->dev, false);
459 mfd_remove_devices(max14577->dev);
460 regmap_del_irq_chip(max14577->irq, max14577->irq_data);
461 if (max14577->dev_type == MAXIM_DEVICE_TYPE_MAX77836)
462 max77836_remove(max14577);
463 }
464
465 static const struct i2c_device_id max14577_i2c_id[] = {
466 { "max14577", MAXIM_DEVICE_TYPE_MAX14577, },
467 { "max77836", MAXIM_DEVICE_TYPE_MAX77836, },
468 { }
469 };
470 MODULE_DEVICE_TABLE(i2c, max14577_i2c_id);
471
max14577_suspend(struct device * dev)472 static int max14577_suspend(struct device *dev)
473 {
474 struct i2c_client *i2c = to_i2c_client(dev);
475 struct max14577 *max14577 = i2c_get_clientdata(i2c);
476
477 if (device_may_wakeup(dev))
478 enable_irq_wake(max14577->irq);
479 /*
480 * MUIC IRQ must be disabled during suspend because if it happens
481 * while suspended it will be handled before resuming I2C.
482 *
483 * When device is woken up from suspend (e.g. by ADC change),
484 * an interrupt occurs before resuming I2C bus controller.
485 * Interrupt handler tries to read registers but this read
486 * will fail because I2C is still suspended.
487 */
488 disable_irq(max14577->irq);
489
490 return 0;
491 }
492
max14577_resume(struct device * dev)493 static int max14577_resume(struct device *dev)
494 {
495 struct i2c_client *i2c = to_i2c_client(dev);
496 struct max14577 *max14577 = i2c_get_clientdata(i2c);
497
498 if (device_may_wakeup(dev))
499 disable_irq_wake(max14577->irq);
500 enable_irq(max14577->irq);
501
502 return 0;
503 }
504
505 static DEFINE_SIMPLE_DEV_PM_OPS(max14577_pm, max14577_suspend, max14577_resume);
506
507 static struct i2c_driver max14577_i2c_driver = {
508 .driver = {
509 .name = "max14577",
510 .pm = pm_sleep_ptr(&max14577_pm),
511 .of_match_table = max14577_dt_match,
512 },
513 .probe = max14577_i2c_probe,
514 .remove = max14577_i2c_remove,
515 .id_table = max14577_i2c_id,
516 };
517
max14577_i2c_init(void)518 static int __init max14577_i2c_init(void)
519 {
520 BUILD_BUG_ON(ARRAY_SIZE(max14577_i2c_id) != MAXIM_DEVICE_TYPE_NUM);
521 BUILD_BUG_ON(ARRAY_SIZE(max14577_dt_match) != MAXIM_DEVICE_TYPE_NUM);
522
523 /* Valid charger current values must be provided for each chipset */
524 BUILD_BUG_ON(ARRAY_SIZE(maxim_charger_currents) != MAXIM_DEVICE_TYPE_NUM);
525
526 /* Check for valid values for charger */
527 BUILD_BUG_ON(MAX14577_CHARGER_CURRENT_LIMIT_HIGH_START +
528 MAX14577_CHARGER_CURRENT_LIMIT_HIGH_STEP * 0xf !=
529 MAX14577_CHARGER_CURRENT_LIMIT_MAX);
530 BUILD_BUG_ON(MAX14577_CHARGER_CURRENT_LIMIT_HIGH_STEP == 0);
531
532 BUILD_BUG_ON(MAX77836_CHARGER_CURRENT_LIMIT_HIGH_START +
533 MAX77836_CHARGER_CURRENT_LIMIT_HIGH_STEP * 0xf !=
534 MAX77836_CHARGER_CURRENT_LIMIT_MAX);
535 BUILD_BUG_ON(MAX77836_CHARGER_CURRENT_LIMIT_HIGH_STEP == 0);
536
537 return i2c_add_driver(&max14577_i2c_driver);
538 }
539 module_init(max14577_i2c_init);
540
max14577_i2c_exit(void)541 static void __exit max14577_i2c_exit(void)
542 {
543 i2c_del_driver(&max14577_i2c_driver);
544 }
545 module_exit(max14577_i2c_exit);
546
547 MODULE_AUTHOR("Chanwoo Choi <cw00.choi@samsung.com>, Krzysztof Kozlowski <krzk@kernel.org>");
548 MODULE_DESCRIPTION("Maxim 14577/77836 multi-function core driver");
549 MODULE_LICENSE("GPL");
550