1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * ROHM BD99954 charger driver
4  *
5  * Copyright (C) 2020 Rohm Semiconductors
6  *	Originally written by:
7  *		Mikko Mutanen <mikko.mutanen@fi.rohmeurope.com>
8  *		Markus Laine <markus.laine@fi.rohmeurope.com>
9  *	Bugs added by:
10  *		Matti Vaittinen <matti.vaittinen@fi.rohmeurope.com>
11  */
12 
13 /*
14  *   The battery charging profile of BD99954.
15  *
16  *   Curve (1) represents charging current.
17  *   Curve (2) represents battery voltage.
18  *
19  *   The BD99954 data sheet divides charging to three phases.
20  *   a) Trickle-charge with constant current (8).
21  *   b) pre-charge with constant current (6)
22  *   c) fast-charge, first with constant current (5) phase. After
23  *      the battery voltage has reached target level (4) we have constant
24  *      voltage phase until charging current has dropped to termination
25  *      level (7)
26  *
27  *    V ^                                                        ^ I
28  *      .                                                        .
29  *      .                                                        .
30  *(4)` `.` ` ` ` ` ` ` ` ` ` ` ` ` ` ----------------------------.
31  *      .                           :/                           .
32  *      .                     o----+/:/ ` ` ` ` ` ` ` ` ` ` ` ` `.` ` (5)
33  *      .                     +   ::  +                          .
34  *      .                     +  /-   --                         .
35  *      .                     +`/-     +                         .
36  *      .                     o/-      -:                        .
37  *      .                    .s.        +`                       .
38  *      .                  .--+         `/                       .
39  *      .               ..``  +          .:                      .
40  *      .             -`      +           --                     .
41  *      .    (2)  ...``       +            :-                    .
42  *      .    ...``            +             -:                   .
43  *(3)` `.`.""  ` ` ` `+-------- ` ` ` ` ` ` `.:` ` ` ` ` ` ` ` ` .` ` (6)
44  *      .             +                       `:.                .
45  *      .             +                         -:               .
46  *      .             +                           -:.            .
47  *      .             +                             .--.         .
48  *      .   (1)       +                                `.+` ` ` `.` ` (7)
49  *      -..............` ` ` ` ` ` ` ` ` ` ` ` ` ` ` ` ` + ` ` ` .` ` (8)
50  *      .                                                +       -
51  *      -------------------------------------------------+++++++++-->
52  *      |   trickle   |  pre  |          fast            |
53  *
54  * Details of DT properties for different limits can be found from BD99954
55  * device tree binding documentation.
56  */
57 
58 #include <linux/delay.h>
59 #include <linux/gpio/consumer.h>
60 #include <linux/interrupt.h>
61 #include <linux/i2c.h>
62 #include <linux/kernel.h>
63 #include <linux/linear_range.h>
64 #include <linux/module.h>
65 #include <linux/mod_devicetable.h>
66 #include <linux/power_supply.h>
67 #include <linux/property.h>
68 #include <linux/regmap.h>
69 #include <linux/types.h>
70 
71 #include "bd99954-charger.h"
72 
73 /* Initial field values, converted to initial register values */
74 struct bd9995x_init_data {
75 	u16 vsysreg_set;	/* VSYS Regulation Setting */
76 	u16 ibus_lim_set;	/* VBUS input current limitation */
77 	u16 icc_lim_set;	/* VCC/VACP Input Current Limit Setting */
78 	u16 itrich_set;		/* Trickle-charge Current Setting */
79 	u16 iprech_set;		/* Pre-Charge Current Setting */
80 	u16 ichg_set;		/* Fast-Charge constant current */
81 	u16 vfastchg_reg_set1;	/* Fast Charging Regulation Voltage */
82 	u16 vprechg_th_set;	/* Pre-charge Voltage Threshold Setting */
83 	u16 vrechg_set;		/* Re-charge Battery Voltage Setting */
84 	u16 vbatovp_set;	/* Battery Over Voltage Threshold Setting */
85 	u16 iterm_set;		/* Charging termination current */
86 };
87 
88 struct bd9995x_state {
89 	u8 online;
90 	u16 chgstm_status;
91 	u16 vbat_vsys_status;
92 	u16 vbus_vcc_status;
93 };
94 
95 struct bd9995x_device {
96 	struct i2c_client *client;
97 	struct device *dev;
98 	struct power_supply *charger;
99 
100 	struct regmap *rmap;
101 	struct regmap_field *rmap_fields[F_MAX_FIELDS];
102 
103 	int chip_id;
104 	int chip_rev;
105 	struct bd9995x_init_data init_data;
106 	struct bd9995x_state state;
107 
108 	struct mutex lock; /* Protect state data */
109 };
110 
111 static const struct regmap_range bd9995x_readonly_reg_ranges[] = {
112 	regmap_reg_range(CHGSTM_STATUS, SEL_ILIM_VAL),
113 	regmap_reg_range(IOUT_DACIN_VAL, IOUT_DACIN_VAL),
114 	regmap_reg_range(VCC_UCD_STATUS, VCC_IDD_STATUS),
115 	regmap_reg_range(VBUS_UCD_STATUS, VBUS_IDD_STATUS),
116 	regmap_reg_range(CHIP_ID, CHIP_REV),
117 	regmap_reg_range(SYSTEM_STATUS, SYSTEM_STATUS),
118 	regmap_reg_range(IBATP_VAL, VBAT_AVE_VAL),
119 	regmap_reg_range(VTH_VAL, EXTIADP_AVE_VAL),
120 };
121 
122 static const struct regmap_access_table bd9995x_writeable_regs = {
123 	.no_ranges = bd9995x_readonly_reg_ranges,
124 	.n_no_ranges = ARRAY_SIZE(bd9995x_readonly_reg_ranges),
125 };
126 
127 static const struct regmap_range bd9995x_volatile_reg_ranges[] = {
128 	regmap_reg_range(CHGSTM_STATUS, WDT_STATUS),
129 	regmap_reg_range(VCC_UCD_STATUS, VCC_IDD_STATUS),
130 	regmap_reg_range(VBUS_UCD_STATUS, VBUS_IDD_STATUS),
131 	regmap_reg_range(INT0_STATUS, INT7_STATUS),
132 	regmap_reg_range(SYSTEM_STATUS, SYSTEM_CTRL_SET),
133 	regmap_reg_range(IBATP_VAL, EXTIADP_AVE_VAL), /* Measurement regs */
134 };
135 
136 static const struct regmap_access_table bd9995x_volatile_regs = {
137 	.yes_ranges = bd9995x_volatile_reg_ranges,
138 	.n_yes_ranges = ARRAY_SIZE(bd9995x_volatile_reg_ranges),
139 };
140 
141 static const struct regmap_range_cfg regmap_range_cfg[] = {
142 	{
143 	.selector_reg     = MAP_SET,
144 	.selector_mask    = 0xFFFF,
145 	.selector_shift   = 0,
146 	.window_start     = 0,
147 	.window_len       = 0x100,
148 	.range_min        = 0 * 0x100,
149 	.range_max        = 3 * 0x100,
150 	},
151 };
152 
153 static const struct regmap_config bd9995x_regmap_config = {
154 	.reg_bits = 8,
155 	.val_bits = 16,
156 	.reg_stride = 1,
157 
158 	.max_register = 3 * 0x100,
159 	.cache_type = REGCACHE_RBTREE,
160 
161 	.ranges = regmap_range_cfg,
162 	.num_ranges = ARRAY_SIZE(regmap_range_cfg),
163 	.val_format_endian = REGMAP_ENDIAN_LITTLE,
164 	.wr_table = &bd9995x_writeable_regs,
165 	.volatile_table = &bd9995x_volatile_regs,
166 };
167 
168 enum bd9995x_chrg_fault {
169 	CHRG_FAULT_NORMAL,
170 	CHRG_FAULT_INPUT,
171 	CHRG_FAULT_THERMAL_SHUTDOWN,
172 	CHRG_FAULT_TIMER_EXPIRED,
173 };
174 
bd9995x_get_prop_batt_health(struct bd9995x_device * bd)175 static int bd9995x_get_prop_batt_health(struct bd9995x_device *bd)
176 {
177 	int ret, tmp;
178 
179 	ret = regmap_field_read(bd->rmap_fields[F_BATTEMP], &tmp);
180 	if (ret)
181 		return POWER_SUPPLY_HEALTH_UNKNOWN;
182 
183 	/* TODO: Check these against datasheet page 34 */
184 
185 	switch (tmp) {
186 	case ROOM:
187 		return POWER_SUPPLY_HEALTH_GOOD;
188 	case HOT1:
189 	case HOT2:
190 	case HOT3:
191 		return POWER_SUPPLY_HEALTH_OVERHEAT;
192 	case COLD1:
193 	case COLD2:
194 		return POWER_SUPPLY_HEALTH_COLD;
195 	case TEMP_DIS:
196 	case BATT_OPEN:
197 	default:
198 		return POWER_SUPPLY_HEALTH_UNKNOWN;
199 	}
200 }
201 
bd9995x_get_prop_charge_type(struct bd9995x_device * bd)202 static int bd9995x_get_prop_charge_type(struct bd9995x_device *bd)
203 {
204 	int ret, tmp;
205 
206 	ret = regmap_field_read(bd->rmap_fields[F_CHGSTM_STATE], &tmp);
207 	if (ret)
208 		return POWER_SUPPLY_CHARGE_TYPE_UNKNOWN;
209 
210 	switch (tmp) {
211 	case CHGSTM_TRICKLE_CHARGE:
212 	case CHGSTM_PRE_CHARGE:
213 		return POWER_SUPPLY_CHARGE_TYPE_TRICKLE;
214 	case CHGSTM_FAST_CHARGE:
215 		return POWER_SUPPLY_CHARGE_TYPE_FAST;
216 	case CHGSTM_TOP_OFF:
217 	case CHGSTM_DONE:
218 	case CHGSTM_SUSPEND:
219 		return POWER_SUPPLY_CHARGE_TYPE_NONE;
220 	default: /* Rest of the states are error related, no charging */
221 		return POWER_SUPPLY_CHARGE_TYPE_NONE;
222 	}
223 }
224 
bd9995x_get_prop_batt_present(struct bd9995x_device * bd)225 static bool bd9995x_get_prop_batt_present(struct bd9995x_device *bd)
226 {
227 	int ret, tmp;
228 
229 	ret = regmap_field_read(bd->rmap_fields[F_BATTEMP], &tmp);
230 	if (ret)
231 		return false;
232 
233 	return tmp != BATT_OPEN;
234 }
235 
bd9995x_get_prop_batt_voltage(struct bd9995x_device * bd)236 static int bd9995x_get_prop_batt_voltage(struct bd9995x_device *bd)
237 {
238 	int ret, tmp;
239 
240 	ret = regmap_field_read(bd->rmap_fields[F_VBAT_VAL], &tmp);
241 	if (ret)
242 		return 0;
243 
244 	tmp = min(tmp, 19200);
245 
246 	return tmp * 1000;
247 }
248 
bd9995x_get_prop_batt_current(struct bd9995x_device * bd)249 static int bd9995x_get_prop_batt_current(struct bd9995x_device *bd)
250 {
251 	int ret, tmp;
252 
253 	ret = regmap_field_read(bd->rmap_fields[F_IBATP_VAL], &tmp);
254 	if (ret)
255 		return 0;
256 
257 	return tmp * 1000;
258 }
259 
260 #define DEFAULT_BATTERY_TEMPERATURE 250
261 
bd9995x_get_prop_batt_temp(struct bd9995x_device * bd)262 static int bd9995x_get_prop_batt_temp(struct bd9995x_device *bd)
263 {
264 	int ret, tmp;
265 
266 	ret = regmap_field_read(bd->rmap_fields[F_THERM_VAL], &tmp);
267 	if (ret)
268 		return DEFAULT_BATTERY_TEMPERATURE;
269 
270 	return (200 - tmp) * 10;
271 }
272 
bd9995x_power_supply_get_property(struct power_supply * psy,enum power_supply_property psp,union power_supply_propval * val)273 static int bd9995x_power_supply_get_property(struct power_supply *psy,
274 					     enum power_supply_property psp,
275 					     union power_supply_propval *val)
276 {
277 	int ret, tmp;
278 	struct bd9995x_device *bd = power_supply_get_drvdata(psy);
279 	struct bd9995x_state state;
280 
281 	mutex_lock(&bd->lock);
282 	state = bd->state;
283 	mutex_unlock(&bd->lock);
284 
285 	switch (psp) {
286 	case POWER_SUPPLY_PROP_STATUS:
287 		switch (state.chgstm_status) {
288 		case CHGSTM_TRICKLE_CHARGE:
289 		case CHGSTM_PRE_CHARGE:
290 		case CHGSTM_FAST_CHARGE:
291 		case CHGSTM_TOP_OFF:
292 			val->intval = POWER_SUPPLY_STATUS_CHARGING;
293 			break;
294 
295 		case CHGSTM_DONE:
296 			val->intval = POWER_SUPPLY_STATUS_FULL;
297 			break;
298 
299 		case CHGSTM_SUSPEND:
300 		case CHGSTM_TEMPERATURE_ERROR_1:
301 		case CHGSTM_TEMPERATURE_ERROR_2:
302 		case CHGSTM_TEMPERATURE_ERROR_3:
303 		case CHGSTM_TEMPERATURE_ERROR_4:
304 		case CHGSTM_TEMPERATURE_ERROR_5:
305 		case CHGSTM_TEMPERATURE_ERROR_6:
306 		case CHGSTM_TEMPERATURE_ERROR_7:
307 		case CHGSTM_THERMAL_SHUT_DOWN_1:
308 		case CHGSTM_THERMAL_SHUT_DOWN_2:
309 		case CHGSTM_THERMAL_SHUT_DOWN_3:
310 		case CHGSTM_THERMAL_SHUT_DOWN_4:
311 		case CHGSTM_THERMAL_SHUT_DOWN_5:
312 		case CHGSTM_THERMAL_SHUT_DOWN_6:
313 		case CHGSTM_THERMAL_SHUT_DOWN_7:
314 		case CHGSTM_BATTERY_ERROR:
315 			val->intval = POWER_SUPPLY_STATUS_NOT_CHARGING;
316 			break;
317 
318 		default:
319 			val->intval = POWER_SUPPLY_STATUS_UNKNOWN;
320 			break;
321 		}
322 		break;
323 
324 	case POWER_SUPPLY_PROP_MANUFACTURER:
325 		val->strval = BD9995X_MANUFACTURER;
326 		break;
327 
328 	case POWER_SUPPLY_PROP_ONLINE:
329 		val->intval = state.online;
330 		break;
331 
332 	case POWER_SUPPLY_PROP_CONSTANT_CHARGE_CURRENT:
333 		ret = regmap_field_read(bd->rmap_fields[F_IBATP_VAL], &tmp);
334 		if (ret)
335 			return ret;
336 		val->intval = tmp * 1000;
337 		break;
338 
339 	case POWER_SUPPLY_PROP_CHARGE_AVG:
340 		ret = regmap_field_read(bd->rmap_fields[F_IBATP_AVE_VAL], &tmp);
341 		if (ret)
342 			return ret;
343 		val->intval = tmp * 1000;
344 		break;
345 
346 	case POWER_SUPPLY_PROP_CONSTANT_CHARGE_CURRENT_MAX:
347 		/*
348 		 * Currently the DT uses this property to give the
349 		 * target current for fast-charging constant current phase.
350 		 * I think it is correct in a sense.
351 		 *
352 		 * Yet, this prop we read and return here is the programmed
353 		 * safety limit for combined input currents. This feels
354 		 * also correct in a sense.
355 		 *
356 		 * However, this results a mismatch to DT value and value
357 		 * read from sysfs.
358 		 */
359 		ret = regmap_field_read(bd->rmap_fields[F_SEL_ILIM_VAL], &tmp);
360 		if (ret)
361 			return ret;
362 		val->intval = tmp * 1000;
363 		break;
364 
365 	case POWER_SUPPLY_PROP_CONSTANT_CHARGE_VOLTAGE:
366 		if (!state.online) {
367 			val->intval = 0;
368 			break;
369 		}
370 
371 		ret = regmap_field_read(bd->rmap_fields[F_VFASTCHG_REG_SET1],
372 					&tmp);
373 		if (ret)
374 			return ret;
375 
376 		/*
377 		 * The actual range : 2560 to 19200 mV. No matter what the
378 		 * register says
379 		 */
380 		val->intval = clamp_val(tmp << 4, 2560, 19200);
381 		val->intval *= 1000;
382 		break;
383 
384 	case POWER_SUPPLY_PROP_CHARGE_TERM_CURRENT:
385 		ret = regmap_field_read(bd->rmap_fields[F_ITERM_SET], &tmp);
386 		if (ret)
387 			return ret;
388 		/* Start step is 64 mA */
389 		val->intval = tmp << 6;
390 		/* Maximum is 1024 mA - no matter what register says */
391 		val->intval = min(val->intval, 1024);
392 		val->intval *= 1000;
393 		break;
394 
395 	/* Battery properties which we access through charger */
396 	case POWER_SUPPLY_PROP_PRESENT:
397 		val->intval = bd9995x_get_prop_batt_present(bd);
398 		break;
399 
400 	case POWER_SUPPLY_PROP_VOLTAGE_NOW:
401 		val->intval = bd9995x_get_prop_batt_voltage(bd);
402 		break;
403 
404 	case POWER_SUPPLY_PROP_CURRENT_NOW:
405 		val->intval = bd9995x_get_prop_batt_current(bd);
406 		break;
407 
408 	case POWER_SUPPLY_PROP_CHARGE_TYPE:
409 		val->intval = bd9995x_get_prop_charge_type(bd);
410 		break;
411 
412 	case POWER_SUPPLY_PROP_HEALTH:
413 		val->intval = bd9995x_get_prop_batt_health(bd);
414 		break;
415 
416 	case POWER_SUPPLY_PROP_TEMP:
417 		val->intval = bd9995x_get_prop_batt_temp(bd);
418 		break;
419 
420 	case POWER_SUPPLY_PROP_TECHNOLOGY:
421 		val->intval = POWER_SUPPLY_TECHNOLOGY_LION;
422 		break;
423 
424 	case POWER_SUPPLY_PROP_MODEL_NAME:
425 		val->strval = "bd99954";
426 		break;
427 
428 	default:
429 		return -EINVAL;
430 
431 	}
432 
433 	return 0;
434 }
435 
bd9995x_get_chip_state(struct bd9995x_device * bd,struct bd9995x_state * state)436 static int bd9995x_get_chip_state(struct bd9995x_device *bd,
437 				  struct bd9995x_state *state)
438 {
439 	int i, ret, tmp;
440 	struct {
441 		struct regmap_field *id;
442 		u16 *data;
443 	} state_fields[] = {
444 		{
445 			bd->rmap_fields[F_CHGSTM_STATE], &state->chgstm_status,
446 		}, {
447 			bd->rmap_fields[F_VBAT_VSYS_STATUS],
448 			&state->vbat_vsys_status,
449 		}, {
450 			bd->rmap_fields[F_VBUS_VCC_STATUS],
451 			&state->vbus_vcc_status,
452 		},
453 	};
454 
455 
456 	for (i = 0; i < ARRAY_SIZE(state_fields); i++) {
457 		ret = regmap_field_read(state_fields[i].id, &tmp);
458 		if (ret)
459 			return ret;
460 
461 		*state_fields[i].data = tmp;
462 	}
463 
464 	if (state->vbus_vcc_status & STATUS_VCC_DET ||
465 	    state->vbus_vcc_status & STATUS_VBUS_DET)
466 		state->online = 1;
467 	else
468 		state->online = 0;
469 
470 	return 0;
471 }
472 
bd9995x_irq_handler_thread(int irq,void * private)473 static irqreturn_t bd9995x_irq_handler_thread(int irq, void *private)
474 {
475 	struct bd9995x_device *bd = private;
476 	int ret, status, mask, i;
477 	unsigned long tmp;
478 	struct bd9995x_state state;
479 
480 	/*
481 	 * The bd9995x does not seem to generate big amount of interrupts.
482 	 * The logic regarding which interrupts can cause relevant
483 	 * status changes seem to be pretty complex.
484 	 *
485 	 * So lets implement really simple and hopefully bullet-proof handler:
486 	 * It does not really matter which IRQ we handle, we just go and
487 	 * re-read all interesting statuses + give the framework a nudge.
488 	 *
489 	 * Other option would be building a _complex_ and error prone logic
490 	 * trying to decide what could have been changed (resulting this IRQ
491 	 * we are now handling). During the normal operation the BD99954 does
492 	 * not seem to be generating much of interrupts so benefit from such
493 	 * logic would probably be minimal.
494 	 */
495 
496 	ret = regmap_read(bd->rmap, INT0_STATUS, &status);
497 	if (ret) {
498 		dev_err(bd->dev, "Failed to read IRQ status\n");
499 		return IRQ_NONE;
500 	}
501 
502 	ret = regmap_field_read(bd->rmap_fields[F_INT0_SET], &mask);
503 	if (ret) {
504 		dev_err(bd->dev, "Failed to read IRQ mask\n");
505 		return IRQ_NONE;
506 	}
507 
508 	/* Handle only IRQs that are not masked */
509 	status &= mask;
510 	tmp = status;
511 
512 	/* Lowest bit does not represent any sub-registers */
513 	tmp >>= 1;
514 
515 	/*
516 	 * Mask and ack IRQs we will handle (+ the idiot bit)
517 	 */
518 	ret = regmap_field_write(bd->rmap_fields[F_INT0_SET], 0);
519 	if (ret) {
520 		dev_err(bd->dev, "Failed to mask F_INT0\n");
521 		return IRQ_NONE;
522 	}
523 
524 	ret = regmap_write(bd->rmap, INT0_STATUS, status);
525 	if (ret) {
526 		dev_err(bd->dev, "Failed to ack F_INT0\n");
527 		goto err_umask;
528 	}
529 
530 	for_each_set_bit(i, &tmp, 7) {
531 		int sub_status, sub_mask;
532 		static const int sub_status_reg[] = {
533 			INT1_STATUS, INT2_STATUS, INT3_STATUS, INT4_STATUS,
534 			INT5_STATUS, INT6_STATUS, INT7_STATUS,
535 		};
536 		struct regmap_field *sub_mask_f[] = {
537 			bd->rmap_fields[F_INT1_SET],
538 			bd->rmap_fields[F_INT2_SET],
539 			bd->rmap_fields[F_INT3_SET],
540 			bd->rmap_fields[F_INT4_SET],
541 			bd->rmap_fields[F_INT5_SET],
542 			bd->rmap_fields[F_INT6_SET],
543 			bd->rmap_fields[F_INT7_SET],
544 		};
545 
546 		/* Clear sub IRQs */
547 		ret = regmap_read(bd->rmap, sub_status_reg[i], &sub_status);
548 		if (ret) {
549 			dev_err(bd->dev, "Failed to read IRQ sub-status\n");
550 			goto err_umask;
551 		}
552 
553 		ret = regmap_field_read(sub_mask_f[i], &sub_mask);
554 		if (ret) {
555 			dev_err(bd->dev, "Failed to read IRQ sub-mask\n");
556 			goto err_umask;
557 		}
558 
559 		/* Ack active sub-statuses */
560 		sub_status &= sub_mask;
561 
562 		ret = regmap_write(bd->rmap, sub_status_reg[i], sub_status);
563 		if (ret) {
564 			dev_err(bd->dev, "Failed to ack sub-IRQ\n");
565 			goto err_umask;
566 		}
567 	}
568 
569 	ret = regmap_field_write(bd->rmap_fields[F_INT0_SET], mask);
570 	if (ret)
571 		/* May as well retry once */
572 		goto err_umask;
573 
574 	/* Read whole chip state */
575 	ret = bd9995x_get_chip_state(bd, &state);
576 	if (ret < 0) {
577 		dev_err(bd->dev, "Failed to read chip state\n");
578 	} else {
579 		mutex_lock(&bd->lock);
580 		bd->state = state;
581 		mutex_unlock(&bd->lock);
582 
583 		power_supply_changed(bd->charger);
584 	}
585 
586 	return IRQ_HANDLED;
587 
588 err_umask:
589 	ret = regmap_field_write(bd->rmap_fields[F_INT0_SET], mask);
590 	if (ret)
591 		dev_err(bd->dev,
592 		"Failed to un-mask F_INT0 - IRQ permanently disabled\n");
593 
594 	return IRQ_NONE;
595 }
596 
__bd9995x_chip_reset(struct bd9995x_device * bd)597 static int __bd9995x_chip_reset(struct bd9995x_device *bd)
598 {
599 	int ret, state;
600 	int rst_check_counter = 10;
601 	u16 tmp = ALLRST | OTPLD;
602 
603 	ret = regmap_raw_write(bd->rmap, SYSTEM_CTRL_SET, &tmp, 2);
604 	if (ret < 0)
605 		return ret;
606 
607 	do {
608 		ret = regmap_field_read(bd->rmap_fields[F_OTPLD_STATE], &state);
609 		if (ret)
610 			return ret;
611 
612 		msleep(10);
613 	} while (state == 0 && --rst_check_counter);
614 
615 	if (!rst_check_counter) {
616 		dev_err(bd->dev, "chip reset not completed\n");
617 		return -ETIMEDOUT;
618 	}
619 
620 	tmp = 0;
621 	ret = regmap_raw_write(bd->rmap, SYSTEM_CTRL_SET, &tmp, 2);
622 
623 	return ret;
624 }
625 
bd9995x_hw_init(struct bd9995x_device * bd)626 static int bd9995x_hw_init(struct bd9995x_device *bd)
627 {
628 	int ret;
629 	int i;
630 	struct bd9995x_state state;
631 	struct bd9995x_init_data *id = &bd->init_data;
632 
633 	const struct {
634 		enum bd9995x_fields id;
635 		u16 value;
636 	} init_data[] = {
637 		/* Enable the charging trigger after SDP charger attached */
638 		{F_SDP_CHG_TRIG_EN,	1},
639 		/* Enable charging trigger after SDP charger attached */
640 		{F_SDP_CHG_TRIG,	1},
641 		/* Disable charging trigger by BC1.2 detection */
642 		{F_VBUS_BC_DISEN,	1},
643 		/* Disable charging trigger by BC1.2 detection */
644 		{F_VCC_BC_DISEN,	1},
645 		/* Disable automatic limitation of the input current */
646 		{F_ILIM_AUTO_DISEN,	1},
647 		/* Select current limitation when SDP charger attached*/
648 		{F_SDP_500_SEL,		1},
649 		/* Select current limitation when DCP charger attached */
650 		{F_DCP_2500_SEL,	1},
651 		{F_VSYSREG_SET,		id->vsysreg_set},
652 		/* Activate USB charging and DC/DC converter */
653 		{F_USB_SUS,		0},
654 		/* DCDC clock: 1200 kHz*/
655 		{F_DCDC_CLK_SEL,	3},
656 		/* Enable charging */
657 		{F_CHG_EN,		1},
658 		/* Disable Input current Limit setting voltage measurement */
659 		{F_EXTIADPEN,		0},
660 		/* Disable input current limiting */
661 		{F_VSYS_PRIORITY,	1},
662 		{F_IBUS_LIM_SET,	id->ibus_lim_set},
663 		{F_ICC_LIM_SET,		id->icc_lim_set},
664 		/* Charge Termination Current Setting to 0*/
665 		{F_ITERM_SET,		id->iterm_set},
666 		/* Trickle-charge Current Setting */
667 		{F_ITRICH_SET,		id->itrich_set},
668 		/* Pre-charge Current setting */
669 		{F_IPRECH_SET,		id->iprech_set},
670 		/* Fast Charge Current for constant current phase */
671 		{F_ICHG_SET,		id->ichg_set},
672 		/* Fast Charge Voltage Regulation Setting */
673 		{F_VFASTCHG_REG_SET1,	id->vfastchg_reg_set1},
674 		/* Set Pre-charge Voltage Threshold for trickle charging. */
675 		{F_VPRECHG_TH_SET,	id->vprechg_th_set},
676 		{F_VRECHG_SET,		id->vrechg_set},
677 		{F_VBATOVP_SET,		id->vbatovp_set},
678 		/* Reverse buck boost voltage Setting */
679 		{F_VRBOOST_SET,		0},
680 		/* Disable fast-charging watchdog */
681 		{F_WDT_FST,		0},
682 		/* Disable pre-charging watchdog */
683 		{F_WDT_PRE,		0},
684 		/* Power save off */
685 		{F_POWER_SAVE_MODE,	0},
686 		{F_INT1_SET,		INT1_ALL},
687 		{F_INT2_SET,		INT2_ALL},
688 		{F_INT3_SET,		INT3_ALL},
689 		{F_INT4_SET,		INT4_ALL},
690 		{F_INT5_SET,		INT5_ALL},
691 		{F_INT6_SET,		INT6_ALL},
692 		{F_INT7_SET,		INT7_ALL},
693 	};
694 
695 	/*
696 	 * Currently we initialize charger to a known state at startup.
697 	 * If we want to allow for example the boot code to initialize
698 	 * charger we should get rid of this.
699 	 */
700 	ret = __bd9995x_chip_reset(bd);
701 	if (ret < 0)
702 		return ret;
703 
704 	/* Initialize currents/voltages and other parameters */
705 	for (i = 0; i < ARRAY_SIZE(init_data); i++) {
706 		ret = regmap_field_write(bd->rmap_fields[init_data[i].id],
707 					 init_data[i].value);
708 		if (ret) {
709 			dev_err(bd->dev, "failed to initialize charger (%d)\n",
710 				ret);
711 			return ret;
712 		}
713 	}
714 
715 	ret = bd9995x_get_chip_state(bd, &state);
716 	if (ret < 0)
717 		return ret;
718 
719 	mutex_lock(&bd->lock);
720 	bd->state = state;
721 	mutex_unlock(&bd->lock);
722 
723 	return 0;
724 }
725 
726 static enum power_supply_property bd9995x_power_supply_props[] = {
727 	POWER_SUPPLY_PROP_MANUFACTURER,
728 	POWER_SUPPLY_PROP_STATUS,
729 	POWER_SUPPLY_PROP_ONLINE,
730 	POWER_SUPPLY_PROP_CONSTANT_CHARGE_CURRENT,
731 	POWER_SUPPLY_PROP_CHARGE_AVG,
732 	POWER_SUPPLY_PROP_CONSTANT_CHARGE_CURRENT_MAX,
733 	POWER_SUPPLY_PROP_CONSTANT_CHARGE_VOLTAGE,
734 	POWER_SUPPLY_PROP_CHARGE_TERM_CURRENT,
735 	/* Battery props we access through charger */
736 	POWER_SUPPLY_PROP_PRESENT,
737 	POWER_SUPPLY_PROP_VOLTAGE_NOW,
738 	POWER_SUPPLY_PROP_CURRENT_NOW,
739 	POWER_SUPPLY_PROP_CHARGE_TYPE,
740 	POWER_SUPPLY_PROP_HEALTH,
741 	POWER_SUPPLY_PROP_TEMP,
742 	POWER_SUPPLY_PROP_TECHNOLOGY,
743 	POWER_SUPPLY_PROP_MODEL_NAME,
744 };
745 
746 static const struct power_supply_desc bd9995x_power_supply_desc = {
747 	.name = "bd9995x-charger",
748 	.type = POWER_SUPPLY_TYPE_USB,
749 	.properties = bd9995x_power_supply_props,
750 	.num_properties = ARRAY_SIZE(bd9995x_power_supply_props),
751 	.get_property = bd9995x_power_supply_get_property,
752 };
753 
754 /*
755  * Limit configurations for vbus-input-current and vcc-vacp-input-current
756  * Minimum limit is 0 uA. Max is 511 * 32000 uA = 16352000 uA. This is
757  * configured by writing a register so that each increment in register
758  * value equals to 32000 uA limit increment.
759  *
760  * Eg, value 0x0 is limit 0, value 0x1 is limit 32000, ...
761  * Describe the setting in linear_range table.
762  */
763 static const struct linear_range input_current_limit_ranges[] = {
764 	LINEAR_RANGE(0, 0x0, 0x1ff, 32000),
765 };
766 
767 /* Possible trickle, pre-charging and termination current values */
768 static const struct linear_range charging_current_ranges[] = {
769 	LINEAR_RANGE(0, 0x0, 0x10, 64000),
770 	LINEAR_RANGE(1024000, 0x11, 0x1f, 0),
771 };
772 
773 /*
774  * Fast charging voltage regulation, starting re-charging limit
775  * and battery over voltage protection have same possible values
776  */
777 static const struct linear_range charge_voltage_regulation_ranges[] = {
778 	LINEAR_RANGE(2560000, 0, 0xA0, 0),
779 	LINEAR_RANGE(2560000, 0xA0, 0x4B0, 16000),
780 	LINEAR_RANGE(19200000, 0x4B0, 0x7FF, 0),
781 };
782 
783 /* Possible VSYS voltage regulation values */
784 static const struct linear_range vsys_voltage_regulation_ranges[] = {
785 	LINEAR_RANGE(2560000, 0, 0x28, 0),
786 	LINEAR_RANGE(2560000, 0x28, 0x12C, 64000),
787 	LINEAR_RANGE(19200000, 0x12C, 0x1FF, 0),
788 };
789 
790 /* Possible settings for switching from trickle to pre-charging limits */
791 static const struct linear_range trickle_to_pre_threshold_ranges[] = {
792 	LINEAR_RANGE(2048000, 0, 0x20, 0),
793 	LINEAR_RANGE(2048000, 0x20, 0x12C, 64000),
794 	LINEAR_RANGE(19200000, 0x12C, 0x1FF, 0),
795 };
796 
797 /* Possible current values for fast-charging constant current phase */
798 static const struct linear_range fast_charge_current_ranges[] = {
799 	LINEAR_RANGE(0, 0, 0xFF, 64000),
800 };
801 
802 struct battery_init {
803 	const char *name;
804 	int *info_data;
805 	const struct linear_range *range;
806 	int ranges;
807 	u16 *data;
808 };
809 
810 struct dt_init {
811 	char *prop;
812 	const struct linear_range *range;
813 	int ranges;
814 	u16 *data;
815 };
816 
bd9995x_fw_probe(struct bd9995x_device * bd)817 static int bd9995x_fw_probe(struct bd9995x_device *bd)
818 {
819 	int ret;
820 	struct power_supply_battery_info *info;
821 	u32 property;
822 	int i;
823 	int regval;
824 	bool found;
825 	struct bd9995x_init_data *init = &bd->init_data;
826 	struct battery_init battery_inits[] = {
827 		{
828 			.name = "trickle-charging current",
829 			.range = &charging_current_ranges[0],
830 			.ranges = 2,
831 			.data = &init->itrich_set,
832 		}, {
833 			.name = "pre-charging current",
834 			.range = &charging_current_ranges[0],
835 			.ranges = 2,
836 			.data = &init->iprech_set,
837 		}, {
838 			.name = "pre-to-trickle charge voltage threshold",
839 			.range = &trickle_to_pre_threshold_ranges[0],
840 			.ranges = 2,
841 			.data = &init->vprechg_th_set,
842 		}, {
843 			.name = "charging termination current",
844 			.range = &charging_current_ranges[0],
845 			.ranges = 2,
846 			.data = &init->iterm_set,
847 		}, {
848 			.name = "charging re-start voltage",
849 			.range = &charge_voltage_regulation_ranges[0],
850 			.ranges = 2,
851 			.data = &init->vrechg_set,
852 		}, {
853 			.name = "battery overvoltage limit",
854 			.range = &charge_voltage_regulation_ranges[0],
855 			.ranges = 2,
856 			.data = &init->vbatovp_set,
857 		}, {
858 			.name = "fast-charging max current",
859 			.range = &fast_charge_current_ranges[0],
860 			.ranges = 1,
861 			.data = &init->ichg_set,
862 		}, {
863 			.name = "fast-charging voltage",
864 			.range = &charge_voltage_regulation_ranges[0],
865 			.ranges = 2,
866 			.data = &init->vfastchg_reg_set1,
867 		},
868 	};
869 	struct dt_init props[] = {
870 		{
871 			.prop = "rohm,vsys-regulation-microvolt",
872 			.range = &vsys_voltage_regulation_ranges[0],
873 			.ranges = 2,
874 			.data = &init->vsysreg_set,
875 		}, {
876 			.prop = "rohm,vbus-input-current-limit-microamp",
877 			.range = &input_current_limit_ranges[0],
878 			.ranges = 1,
879 			.data = &init->ibus_lim_set,
880 		}, {
881 			.prop = "rohm,vcc-input-current-limit-microamp",
882 			.range = &input_current_limit_ranges[0],
883 			.ranges = 1,
884 			.data = &init->icc_lim_set,
885 		},
886 	};
887 
888 	/*
889 	 * The power_supply_get_battery_info() does not support getting values
890 	 * from ACPI. Let's fix it if ACPI is required here.
891 	 */
892 	ret = power_supply_get_battery_info(bd->charger, &info);
893 	if (ret < 0)
894 		return ret;
895 
896 	/* Put pointers to the generic battery info */
897 	battery_inits[0].info_data = &info->tricklecharge_current_ua;
898 	battery_inits[1].info_data = &info->precharge_current_ua;
899 	battery_inits[2].info_data = &info->precharge_voltage_max_uv;
900 	battery_inits[3].info_data = &info->charge_term_current_ua;
901 	battery_inits[4].info_data = &info->charge_restart_voltage_uv;
902 	battery_inits[5].info_data = &info->overvoltage_limit_uv;
903 	battery_inits[6].info_data = &info->constant_charge_current_max_ua;
904 	battery_inits[7].info_data = &info->constant_charge_voltage_max_uv;
905 
906 	for (i = 0; i < ARRAY_SIZE(battery_inits); i++) {
907 		int val = *battery_inits[i].info_data;
908 		const struct linear_range *range = battery_inits[i].range;
909 		int ranges = battery_inits[i].ranges;
910 
911 		if (val == -EINVAL)
912 			continue;
913 
914 		ret = linear_range_get_selector_low_array(range, ranges, val,
915 							  &regval, &found);
916 		if (ret) {
917 			dev_err(bd->dev, "Unsupported value for %s\n",
918 				battery_inits[i].name);
919 
920 			power_supply_put_battery_info(bd->charger, info);
921 			return -EINVAL;
922 		}
923 		if (!found) {
924 			dev_warn(bd->dev,
925 				 "Unsupported value for %s - using smaller\n",
926 				 battery_inits[i].name);
927 		}
928 		*(battery_inits[i].data) = regval;
929 	}
930 
931 	power_supply_put_battery_info(bd->charger, info);
932 
933 	for (i = 0; i < ARRAY_SIZE(props); i++) {
934 		ret = device_property_read_u32(bd->dev, props[i].prop,
935 					       &property);
936 		if (ret < 0) {
937 			dev_err(bd->dev, "failed to read %s", props[i].prop);
938 
939 			return ret;
940 		}
941 
942 		ret = linear_range_get_selector_low_array(props[i].range,
943 							  props[i].ranges,
944 							  property, &regval,
945 							  &found);
946 		if (ret) {
947 			dev_err(bd->dev, "Unsupported value for '%s'\n",
948 				props[i].prop);
949 
950 			return -EINVAL;
951 		}
952 
953 		if (!found) {
954 			dev_warn(bd->dev,
955 				 "Unsupported value for '%s' - using smaller\n",
956 				 props[i].prop);
957 		}
958 
959 		*(props[i].data) = regval;
960 	}
961 
962 	return 0;
963 }
964 
bd9995x_chip_reset(void * bd)965 static void bd9995x_chip_reset(void *bd)
966 {
967 	__bd9995x_chip_reset(bd);
968 }
969 
bd9995x_probe(struct i2c_client * client)970 static int bd9995x_probe(struct i2c_client *client)
971 {
972 	struct device *dev = &client->dev;
973 	struct bd9995x_device *bd;
974 	struct power_supply_config psy_cfg = {};
975 	int ret;
976 	int i;
977 
978 	bd = devm_kzalloc(dev, sizeof(*bd), GFP_KERNEL);
979 	if (!bd)
980 		return -ENOMEM;
981 
982 	bd->client = client;
983 	bd->dev = dev;
984 	psy_cfg.drv_data = bd;
985 	psy_cfg.of_node = dev->of_node;
986 
987 	mutex_init(&bd->lock);
988 
989 	bd->rmap = devm_regmap_init_i2c(client, &bd9995x_regmap_config);
990 	if (IS_ERR(bd->rmap)) {
991 		dev_err(dev, "Failed to setup register access via i2c\n");
992 		return PTR_ERR(bd->rmap);
993 	}
994 
995 	for (i = 0; i < ARRAY_SIZE(bd9995x_reg_fields); i++) {
996 		const struct reg_field *reg_fields = bd9995x_reg_fields;
997 
998 		bd->rmap_fields[i] = devm_regmap_field_alloc(dev, bd->rmap,
999 							     reg_fields[i]);
1000 		if (IS_ERR(bd->rmap_fields[i])) {
1001 			dev_err(dev, "cannot allocate regmap field\n");
1002 			return PTR_ERR(bd->rmap_fields[i]);
1003 		}
1004 	}
1005 
1006 	i2c_set_clientdata(client, bd);
1007 
1008 	ret = regmap_field_read(bd->rmap_fields[F_CHIP_ID], &bd->chip_id);
1009 	if (ret) {
1010 		dev_err(dev, "Cannot read chip ID.\n");
1011 		return ret;
1012 	}
1013 
1014 	if (bd->chip_id != BD99954_ID) {
1015 		dev_err(dev, "Chip with ID=0x%x, not supported!\n",
1016 			bd->chip_id);
1017 		return -ENODEV;
1018 	}
1019 
1020 	ret = regmap_field_read(bd->rmap_fields[F_CHIP_REV], &bd->chip_rev);
1021 	if (ret) {
1022 		dev_err(dev, "Cannot read revision.\n");
1023 		return ret;
1024 	}
1025 
1026 	dev_info(bd->dev, "Found BD99954 chip rev %d\n", bd->chip_rev);
1027 
1028 	/*
1029 	 * We need to init the psy before we can call
1030 	 * power_supply_get_battery_info() for it
1031 	 */
1032 	bd->charger = devm_power_supply_register(bd->dev,
1033 						 &bd9995x_power_supply_desc,
1034 						&psy_cfg);
1035 	if (IS_ERR(bd->charger)) {
1036 		dev_err(dev, "Failed to register power supply\n");
1037 		return PTR_ERR(bd->charger);
1038 	}
1039 
1040 	ret = bd9995x_fw_probe(bd);
1041 	if (ret < 0) {
1042 		dev_err(dev, "Cannot read device properties.\n");
1043 		return ret;
1044 	}
1045 
1046 	ret = bd9995x_hw_init(bd);
1047 	if (ret < 0) {
1048 		dev_err(dev, "Cannot initialize the chip.\n");
1049 		return ret;
1050 	}
1051 
1052 	ret = devm_add_action_or_reset(dev, bd9995x_chip_reset, bd);
1053 	if (ret)
1054 		return ret;
1055 
1056 	return devm_request_threaded_irq(dev, client->irq, NULL,
1057 					 bd9995x_irq_handler_thread,
1058 					 IRQF_TRIGGER_LOW | IRQF_ONESHOT,
1059 					 BD9995X_IRQ_PIN, bd);
1060 }
1061 
1062 static const struct of_device_id bd9995x_of_match[] = {
1063 	{ .compatible = "rohm,bd99954", },
1064 	{ }
1065 };
1066 MODULE_DEVICE_TABLE(of, bd9995x_of_match);
1067 
1068 static struct i2c_driver bd9995x_driver = {
1069 	.driver = {
1070 		.name = "bd9995x-charger",
1071 		.of_match_table = bd9995x_of_match,
1072 	},
1073 	.probe = bd9995x_probe,
1074 };
1075 module_i2c_driver(bd9995x_driver);
1076 
1077 MODULE_AUTHOR("Laine Markus <markus.laine@fi.rohmeurope.com>");
1078 MODULE_DESCRIPTION("ROHM BD99954 charger driver");
1079 MODULE_LICENSE("GPL");
1080