1 // SPDX-License-Identifier: GPL-2.0+
3 * Charger Driver for Rockchip rk817
5 * Copyright (c) 2021 Maya Matuszczyk <maccraft123mc@gmail.com>
7 * Authors: Maya Matuszczyk <maccraft123mc@gmail.com>
8 * Chris Morgan <macromorgan@hotmail.com>
11 #include <asm/unaligned.h>
12 #include <linux/devm-helpers.h>
13 #include <linux/mfd/rk808.h>
14 #include <linux/irq.h>
16 #include <linux/platform_device.h>
17 #include <linux/power_supply.h>
18 #include <linux/regmap.h>
20 /* Charging statuses reported by hardware register */
21 enum rk817_charge_status {
33 * Max charging current read to/written from hardware register.
34 * Note how highest value corresponding to 0x7 is the lowest
35 * current, this is per the datasheet.
48 struct rk817_charger {
52 struct power_supply *bat_ps;
53 struct power_supply *chg_ps;
58 * voltage_k and voltage_b values are used to calibrate the ADC
59 * voltage readings. While they are documented in the BSP kernel and
60 * datasheet as voltage_k and voltage_b, there is no further
61 * information explaining them in more detail.
68 * soc - state of charge - like the BSP this is stored as a percentage,
69 * to the thousandth. BSP has a display state of charge (dsoc) and a
70 * remaining state of charge (rsoc). This value will be used for both
71 * purposes here so we don't do any fancy math to try and "smooth" the
72 * charge and just report it as it is. Note for example an soc of 100
73 * is stored as 100000, an soc of 50 is stored as 50000, etc.
78 * Capacity of battery when fully charged, equal or less than design
79 * capacity depending upon wear. BSP kernel saves to nvram in mAh,
80 * so this value is in mAh not the standard uAh.
85 * Calibrate the SOC on a fully charged battery, this way we can use
86 * the calibrated SOC value to correct for columb counter drift.
90 /* Implementation specific immutable properties from device tree */
92 int sleep_enter_current_ua;
93 int sleep_filter_current_ua;
94 int bat_charge_full_design_uah;
95 int bat_voltage_min_design_uv;
96 int bat_voltage_max_design_uv;
98 /* Values updated periodically by driver for display. */
105 int charger_input_volt_avg_uv;
107 /* Work queue to periodically update values. */
108 struct delayed_work work;
111 /* ADC coefficients extracted from BSP kernel */
112 #define ADC_TO_CURRENT(adc_value, res_div) \
113 (adc_value * 172 / res_div)
115 #define CURRENT_TO_ADC(current, samp_res) \
116 (current * samp_res / 172)
118 #define CHARGE_TO_ADC(capacity, res_div) \
119 (capacity * res_div * 3600 / 172 * 1000)
121 #define ADC_TO_CHARGE_UAH(adc_value, res_div) \
122 (adc_value / 3600 * 172 / res_div)
124 static int rk817_chg_cur_to_reg(u32 chg_cur_ma)
126 if (chg_cur_ma >= 3500)
128 else if (chg_cur_ma >= 3000)
130 else if (chg_cur_ma >= 2750)
132 else if (chg_cur_ma >= 2500)
134 else if (chg_cur_ma >= 2000)
136 else if (chg_cur_ma >= 1500)
138 else if (chg_cur_ma >= 1000)
140 else if (chg_cur_ma >= 500)
146 static int rk817_chg_cur_from_reg(u8 reg)
170 static void rk817_bat_calib_vol(struct rk817_charger *charger)
172 uint32_t vcalib0 = 0;
173 uint32_t vcalib1 = 0;
176 /* calibrate voltage */
177 regmap_bulk_read(charger->rk808->regmap, RK817_GAS_GAUGE_VCALIB0_H,
179 vcalib0 = get_unaligned_be16(bulk_reg);
181 regmap_bulk_read(charger->rk808->regmap, RK817_GAS_GAUGE_VCALIB1_H,
183 vcalib1 = get_unaligned_be16(bulk_reg);
185 /* values were taken from BSP kernel */
186 charger->voltage_k = (4025 - 2300) * 1000 /
187 ((vcalib1 - vcalib0) ? (vcalib1 - vcalib0) : 1);
188 charger->voltage_b = 4025 - (charger->voltage_k * vcalib1) / 1000;
191 static void rk817_bat_calib_cur(struct rk817_charger *charger)
195 /* calibrate current */
196 regmap_bulk_read(charger->rk808->regmap, RK817_GAS_GAUGE_IOFFSET_H,
198 regmap_bulk_write(charger->rk808->regmap, RK817_GAS_GAUGE_CAL_OFFSET_H,
203 * note that only the fcc_mah is really used by this driver, the other values
204 * are to ensure we can remain backwards compatible with the BSP kernel.
206 static int rk817_record_battery_nvram_values(struct rk817_charger *charger)
212 * write the soc value to the nvram location used by the BSP kernel
213 * for the dsoc value.
215 put_unaligned_le24(charger->soc, bulk_reg);
216 ret = regmap_bulk_write(charger->rk808->regmap, RK817_GAS_GAUGE_BAT_R1,
221 * write the remaining capacity in mah to the nvram location used by
222 * the BSP kernel for the rsoc value.
224 rsoc = (charger->soc * charger->fcc_mah) / 100000;
225 put_unaligned_le24(rsoc, bulk_reg);
226 ret = regmap_bulk_write(charger->rk808->regmap, RK817_GAS_GAUGE_DATA0,
230 /* write the fcc_mah in mAh, just as the BSP kernel does. */
231 put_unaligned_le24(charger->fcc_mah, bulk_reg);
232 ret = regmap_bulk_write(charger->rk808->regmap, RK817_GAS_GAUGE_DATA3,
240 static int rk817_bat_calib_cap(struct rk817_charger *charger)
242 struct rk808 *rk808 = charger->rk808;
243 int tmp, charge_now, charge_now_adc, volt_avg;
246 /* Calibrate the soc and fcc on a fully charged battery */
248 if (charger->charge_status == CHARGE_FINISH && (!charger->soc_cal)) {
250 * soc should be 100000 and columb counter should show the full
251 * charge capacity. Note that if the device is unplugged for a
252 * period of several days the columb counter will have a large
253 * margin of error, so setting it back to the full charge on
254 * a completed charge cycle should correct this (my device was
255 * showing 33% battery after 3 days unplugged when it should
256 * have been closer to 95% based on voltage and charge
260 charger->soc = 100000;
261 charge_now_adc = CHARGE_TO_ADC(charger->fcc_mah,
263 put_unaligned_be32(charge_now_adc, bulk_reg);
264 regmap_bulk_write(rk808->regmap, RK817_GAS_GAUGE_Q_INIT_H3,
267 charger->soc_cal = 1;
268 dev_dbg(charger->dev,
269 "Fully charged. SOC is %d, full capacity is %d\n",
270 charger->soc, charger->fcc_mah * 1000);
274 * The columb counter can drift up slightly, so we should correct for
275 * it. But don't correct it until we're at 100% soc.
277 if (charger->charge_status == CHARGE_FINISH && charger->soc_cal) {
278 regmap_bulk_read(rk808->regmap, RK817_GAS_GAUGE_Q_PRES_H3,
280 charge_now_adc = get_unaligned_be32(bulk_reg);
281 if (charge_now_adc < 0)
282 return charge_now_adc;
283 charge_now = ADC_TO_CHARGE_UAH(charge_now_adc,
287 * Re-init columb counter with updated values to correct drift.
289 if (charge_now / 1000 > charger->fcc_mah) {
290 dev_dbg(charger->dev,
291 "Recalibrating columb counter to %d uah\n",
294 * Order of operations matters here to ensure we keep
295 * enough precision until the last step to keep from
296 * making needless updates to columb counter.
298 charge_now_adc = CHARGE_TO_ADC(charger->fcc_mah,
300 put_unaligned_be32(charge_now_adc, bulk_reg);
301 regmap_bulk_write(rk808->regmap,
302 RK817_GAS_GAUGE_Q_INIT_H3,
308 * Calibrate the fully charged capacity when we previously had a full
309 * battery (soc_cal = 1) and are now empty (at or below minimum design
310 * voltage). If our columb counter is still positive, subtract that
311 * from our fcc value to get a calibrated fcc, and if our columb
312 * counter is negative add that to our fcc (but not to exceed our
315 regmap_bulk_read(charger->rk808->regmap, RK817_GAS_GAUGE_BAT_VOL_H,
317 tmp = get_unaligned_be16(bulk_reg);
318 volt_avg = (charger->voltage_k * tmp) + 1000 * charger->voltage_b;
319 if (volt_avg <= charger->bat_voltage_min_design_uv &&
321 regmap_bulk_read(rk808->regmap, RK817_GAS_GAUGE_Q_PRES_H3,
323 charge_now_adc = get_unaligned_be32(bulk_reg);
324 charge_now = ADC_TO_CHARGE_UAH(charge_now_adc,
327 * Note, if charge_now is negative this will add it (what we
328 * want) and if it's positive this will subtract (also what
331 charger->fcc_mah = charger->fcc_mah - (charge_now / 1000);
333 dev_dbg(charger->dev,
334 "Recalibrating full charge capacity to %d uah\n",
335 charger->fcc_mah * 1000);
339 * Set the SOC to 0 if we are below the minimum system voltage.
341 if (volt_avg <= charger->bat_voltage_min_design_uv) {
343 charge_now_adc = CHARGE_TO_ADC(0, charger->res_div);
344 put_unaligned_be32(charge_now_adc, bulk_reg);
345 regmap_bulk_write(rk808->regmap,
346 RK817_GAS_GAUGE_Q_INIT_H3, bulk_reg, 4);
347 dev_warn(charger->dev,
348 "Battery voltage %d below minimum voltage %d\n",
349 volt_avg, charger->bat_voltage_min_design_uv);
352 rk817_record_battery_nvram_values(charger);
357 static void rk817_read_props(struct rk817_charger *charger)
363 * Recalibrate voltage and current readings if we need to BSP does both
364 * on CUR_CALIB_UPD, ignoring VOL_CALIB_UPD. Curiously enough, both
365 * documentation and the BSP show that you perform an update if bit 7
366 * is 1, but you clear the status by writing a 1 to bit 7.
368 regmap_read(charger->rk808->regmap, RK817_GAS_GAUGE_ADC_CONFIG1, ®);
369 if (reg & RK817_VOL_CUR_CALIB_UPD) {
370 rk817_bat_calib_cur(charger);
371 rk817_bat_calib_vol(charger);
372 regmap_write_bits(charger->rk808->regmap,
373 RK817_GAS_GAUGE_ADC_CONFIG1,
374 RK817_VOL_CUR_CALIB_UPD,
375 RK817_VOL_CUR_CALIB_UPD);
378 /* Update reported charge. */
379 regmap_bulk_read(charger->rk808->regmap, RK817_GAS_GAUGE_Q_PRES_H3,
381 tmp = get_unaligned_be32(bulk_reg);
382 charger->charge_now_uah = ADC_TO_CHARGE_UAH(tmp, charger->res_div);
383 if (charger->charge_now_uah < 0)
384 charger->charge_now_uah = 0;
385 if (charger->charge_now_uah > charger->fcc_mah * 1000)
386 charger->charge_now_uah = charger->fcc_mah * 1000;
388 /* Update soc based on reported charge. */
389 charger->soc = charger->charge_now_uah * 100 / charger->fcc_mah;
391 /* Update reported voltage. */
392 regmap_bulk_read(charger->rk808->regmap, RK817_GAS_GAUGE_BAT_VOL_H,
394 tmp = get_unaligned_be16(bulk_reg);
395 charger->volt_avg_uv = (charger->voltage_k * tmp) + 1000 *
399 * Update reported current. Note value from registers is a signed 16
402 regmap_bulk_read(charger->rk808->regmap, RK817_GAS_GAUGE_BAT_CUR_H,
404 tmp = (short int)get_unaligned_be16(bulk_reg);
405 charger->cur_avg_ua = ADC_TO_CURRENT(tmp, charger->res_div);
408 * Update the max charge current. This value shouldn't change, but we
409 * can read it to report what the PMIC says it is instead of simply
410 * returning the default value.
412 regmap_read(charger->rk808->regmap, RK817_PMIC_CHRG_OUT, ®);
413 charger->max_chg_cur_ua =
414 rk817_chg_cur_from_reg(reg & RK817_CHRG_CUR_SEL);
417 * Update max charge voltage. Like the max charge current this value
418 * shouldn't change, but we can report what the PMIC says.
420 regmap_read(charger->rk808->regmap, RK817_PMIC_CHRG_OUT, ®);
421 charger->max_chg_volt_uv = ((((reg & RK817_CHRG_VOL_SEL) >> 4) *
424 /* Check if battery still present. */
425 regmap_read(charger->rk808->regmap, RK817_PMIC_CHRG_STS, ®);
426 charger->battery_present = (reg & RK817_BAT_EXS);
428 /* Get which type of charge we are using (if any). */
429 regmap_read(charger->rk808->regmap, RK817_PMIC_CHRG_STS, ®);
430 charger->charge_status = (reg >> 4) & 0x07;
433 * Get charger input voltage. Note that on my example hardware (an
434 * Odroid Go Advance) the voltage of the power connector is measured
435 * on the register labelled USB in the datasheet; I don't know if this
436 * is how it is designed or just a quirk of the implementation. I
437 * believe this will also measure the voltage of the USB output when in
438 * OTG mode, if that is the case we may need to change this in the
439 * future to return 0 if the power supply status is offline (I can't
440 * test this with my current implementation. Also, when the voltage
441 * should be zero sometimes the ADC still shows a single bit (which
442 * would register as 20000uv). When this happens set it to 0.
444 regmap_bulk_read(charger->rk808->regmap, RK817_GAS_GAUGE_USB_VOL_H,
446 reg = get_unaligned_be16(bulk_reg);
448 tmp = ((charger->voltage_k * reg / 1000 + charger->voltage_b) *
450 charger->charger_input_volt_avg_uv = tmp * 1000;
452 charger->charger_input_volt_avg_uv = 0;
455 /* Calibrate battery capacity and soc. */
456 rk817_bat_calib_cap(charger);
459 static int rk817_bat_get_prop(struct power_supply *ps,
460 enum power_supply_property prop,
461 union power_supply_propval *val)
463 struct rk817_charger *charger = power_supply_get_drvdata(ps);
466 case POWER_SUPPLY_PROP_PRESENT:
467 val->intval = charger->battery_present;
469 case POWER_SUPPLY_PROP_STATUS:
470 if (charger->cur_avg_ua < 0) {
471 val->intval = POWER_SUPPLY_STATUS_DISCHARGING;
474 switch (charger->charge_status) {
476 val->intval = POWER_SUPPLY_STATUS_NOT_CHARGING;
479 * Dead charge is documented, but not explained. I never
480 * observed it but assume it's a pre-charge for a dead
486 val->intval = POWER_SUPPLY_STATUS_CHARGING;
489 val->intval = POWER_SUPPLY_STATUS_FULL;
492 val->intval = POWER_SUPPLY_STATUS_UNKNOWN;
497 case POWER_SUPPLY_PROP_CHARGE_TYPE:
498 switch (charger->charge_status) {
501 val->intval = POWER_SUPPLY_CHARGE_TYPE_NONE;
504 val->intval = POWER_SUPPLY_CHARGE_TYPE_TRICKLE;
508 val->intval = POWER_SUPPLY_CHARGE_TYPE_STANDARD;
511 val->intval = POWER_SUPPLY_CHARGE_TYPE_UNKNOWN;
515 case POWER_SUPPLY_PROP_CHARGE_FULL:
516 val->intval = charger->fcc_mah * 1000;
518 case POWER_SUPPLY_PROP_CHARGE_FULL_DESIGN:
519 val->intval = charger->bat_charge_full_design_uah;
521 case POWER_SUPPLY_PROP_CHARGE_EMPTY_DESIGN:
524 case POWER_SUPPLY_PROP_CHARGE_NOW:
525 val->intval = charger->charge_now_uah;
527 case POWER_SUPPLY_PROP_VOLTAGE_MIN_DESIGN:
528 val->intval = charger->bat_voltage_min_design_uv;
530 case POWER_SUPPLY_PROP_CAPACITY:
531 /* Add 500 so that values like 99999 are 100% not 99%. */
532 val->intval = (charger->soc + 500) / 1000;
533 if (val->intval > 100)
538 case POWER_SUPPLY_PROP_VOLTAGE_AVG:
539 val->intval = charger->volt_avg_uv;
541 case POWER_SUPPLY_PROP_CURRENT_AVG:
542 val->intval = charger->cur_avg_ua;
544 case POWER_SUPPLY_PROP_CONSTANT_CHARGE_CURRENT_MAX:
545 val->intval = charger->max_chg_cur_ua;
547 case POWER_SUPPLY_PROP_CONSTANT_CHARGE_VOLTAGE_MAX:
548 val->intval = charger->max_chg_volt_uv;
550 case POWER_SUPPLY_PROP_VOLTAGE_MAX_DESIGN:
551 val->intval = charger->bat_voltage_max_design_uv;
559 static int rk817_chg_get_prop(struct power_supply *ps,
560 enum power_supply_property prop,
561 union power_supply_propval *val)
563 struct rk817_charger *charger = power_supply_get_drvdata(ps);
566 case POWER_SUPPLY_PROP_ONLINE:
567 val->intval = charger->plugged_in;
569 case POWER_SUPPLY_PROP_VOLTAGE_MAX_DESIGN:
570 /* max voltage from datasheet at 5.5v (default 5.0v) */
571 val->intval = 5500000;
573 case POWER_SUPPLY_PROP_VOLTAGE_MIN_DESIGN:
574 /* min voltage from datasheet at 3.8v (default 5.0v) */
575 val->intval = 3800000;
577 case POWER_SUPPLY_PROP_VOLTAGE_AVG:
578 val->intval = charger->charger_input_volt_avg_uv;
581 * While it's possible that other implementations could use different
582 * USB types, the current implementation for this PMIC (the Odroid Go
583 * Advance) only uses a dedicated charging port with no rx/tx lines.
585 case POWER_SUPPLY_PROP_USB_TYPE:
586 val->intval = POWER_SUPPLY_USB_TYPE_DCP;
595 static irqreturn_t rk817_plug_in_isr(int irq, void *cg)
597 struct rk817_charger *charger;
599 charger = (struct rk817_charger *)cg;
600 charger->plugged_in = 1;
601 power_supply_changed(charger->chg_ps);
602 power_supply_changed(charger->bat_ps);
603 /* try to recalibrate capacity if we hit full charge. */
604 charger->soc_cal = 0;
606 rk817_read_props(charger);
608 dev_dbg(charger->dev, "Power Cord Inserted\n");
613 static irqreturn_t rk817_plug_out_isr(int irq, void *cg)
615 struct rk817_charger *charger;
618 charger = (struct rk817_charger *)cg;
619 rk808 = charger->rk808;
620 charger->plugged_in = 0;
621 power_supply_changed(charger->bat_ps);
622 power_supply_changed(charger->chg_ps);
625 * For some reason the bits of RK817_PMIC_CHRG_IN reset whenever the
626 * power cord is unplugged. This was not documented in the BSP kernel
627 * or the datasheet and only discovered by trial and error. Set minimum
628 * USB input voltage to 4.5v and enable USB voltage input limit.
630 regmap_write_bits(rk808->regmap, RK817_PMIC_CHRG_IN,
631 RK817_USB_VLIM_SEL, (0x05 << 4));
632 regmap_write_bits(rk808->regmap, RK817_PMIC_CHRG_IN, RK817_USB_VLIM_EN,
636 * Set average USB input current limit to 1.5A and enable USB current
639 regmap_write_bits(rk808->regmap, RK817_PMIC_CHRG_IN,
640 RK817_USB_ILIM_SEL, 0x03);
641 regmap_write_bits(rk808->regmap, RK817_PMIC_CHRG_IN, RK817_USB_ILIM_EN,
644 rk817_read_props(charger);
646 dev_dbg(charger->dev, "Power Cord Removed\n");
651 static enum power_supply_property rk817_bat_props[] = {
652 POWER_SUPPLY_PROP_PRESENT,
653 POWER_SUPPLY_PROP_STATUS,
654 POWER_SUPPLY_PROP_CHARGE_TYPE,
655 POWER_SUPPLY_PROP_CHARGE_FULL,
656 POWER_SUPPLY_PROP_CHARGE_FULL_DESIGN,
657 POWER_SUPPLY_PROP_CHARGE_EMPTY_DESIGN,
658 POWER_SUPPLY_PROP_CHARGE_NOW,
659 POWER_SUPPLY_PROP_CONSTANT_CHARGE_VOLTAGE_MAX,
660 POWER_SUPPLY_PROP_VOLTAGE_AVG,
661 POWER_SUPPLY_PROP_CONSTANT_CHARGE_CURRENT_MAX,
662 POWER_SUPPLY_PROP_CURRENT_AVG,
663 POWER_SUPPLY_PROP_VOLTAGE_MIN_DESIGN,
664 POWER_SUPPLY_PROP_CAPACITY,
665 POWER_SUPPLY_PROP_VOLTAGE_MAX_DESIGN,
668 static enum power_supply_property rk817_chg_props[] = {
669 POWER_SUPPLY_PROP_ONLINE,
670 POWER_SUPPLY_PROP_USB_TYPE,
671 POWER_SUPPLY_PROP_VOLTAGE_MAX_DESIGN,
672 POWER_SUPPLY_PROP_VOLTAGE_MIN_DESIGN,
673 POWER_SUPPLY_PROP_VOLTAGE_AVG,
676 static enum power_supply_usb_type rk817_usb_type[] = {
677 POWER_SUPPLY_USB_TYPE_DCP,
678 POWER_SUPPLY_USB_TYPE_UNKNOWN,
681 static const struct power_supply_desc rk817_bat_desc = {
682 .name = "rk817-battery",
683 .type = POWER_SUPPLY_TYPE_BATTERY,
684 .properties = rk817_bat_props,
685 .num_properties = ARRAY_SIZE(rk817_bat_props),
686 .get_property = rk817_bat_get_prop,
689 static const struct power_supply_desc rk817_chg_desc = {
690 .name = "rk817-charger",
691 .type = POWER_SUPPLY_TYPE_USB,
692 .usb_types = rk817_usb_type,
693 .num_usb_types = ARRAY_SIZE(rk817_usb_type),
694 .properties = rk817_chg_props,
695 .num_properties = ARRAY_SIZE(rk817_chg_props),
696 .get_property = rk817_chg_get_prop,
699 static int rk817_read_battery_nvram_values(struct rk817_charger *charger)
704 /* Read the nvram data for full charge capacity. */
705 ret = regmap_bulk_read(charger->rk808->regmap,
706 RK817_GAS_GAUGE_DATA3, bulk_reg, 3);
709 charger->fcc_mah = get_unaligned_le24(bulk_reg);
712 * Sanity checking for values equal to zero or less than would be
713 * practical for this device (BSP Kernel assumes 500mAH or less) for
714 * practicality purposes. Also check if the value is too large and
717 if ((charger->fcc_mah < 500) ||
718 ((charger->fcc_mah * 1000) > charger->bat_charge_full_design_uah)) {
719 dev_info(charger->dev,
720 "Invalid NVRAM max charge, setting to %u uAH\n",
721 charger->bat_charge_full_design_uah);
722 charger->fcc_mah = charger->bat_charge_full_design_uah / 1000;
726 * Read the nvram for state of charge. Sanity check for values greater
727 * than 100 (10000) or less than 0, because other things (BSP kernels,
728 * U-Boot, or even i2cset) can write to this register. If the value is
729 * off it should get corrected automatically when the voltage drops to
730 * the min (soc is 0) or when the battery is full (soc is 100).
732 ret = regmap_bulk_read(charger->rk808->regmap,
733 RK817_GAS_GAUGE_BAT_R1, bulk_reg, 3);
736 charger->soc = get_unaligned_le24(bulk_reg);
737 if (charger->soc > 10000)
738 charger->soc = 10000;
739 if (charger->soc < 0)
746 rk817_read_or_set_full_charge_on_boot(struct rk817_charger *charger,
747 struct power_supply_battery_info *bat_info)
749 struct rk808 *rk808 = charger->rk808;
751 u32 boot_voltage, boot_charge_mah;
752 int ret, reg, off_time, tmp;
756 * Check if the battery is uninitalized. If it is, the columb counter
757 * needs to be set up.
759 ret = regmap_read(rk808->regmap, RK817_GAS_GAUGE_GG_STS, ®);
762 first_boot = reg & RK817_BAT_CON;
764 * If the battery is uninitialized, use the poweron voltage and an ocv
765 * lookup to guess our charge. The number won't be very accurate until
766 * we hit either our minimum voltage (0%) or full charge (100%).
769 regmap_bulk_read(rk808->regmap, RK817_GAS_GAUGE_PWRON_VOL_H,
771 tmp = get_unaligned_be16(bulk_reg);
772 boot_voltage = (charger->voltage_k * tmp) +
773 1000 * charger->voltage_b;
775 * Since only implementation has no working thermistor, assume
776 * 20C for OCV lookup. If lookup fails, report error with OCV
779 charger->soc = power_supply_batinfo_ocv2cap(bat_info,
782 if (charger->soc < 0)
785 /* Guess that full charge capacity is the design capacity */
786 charger->fcc_mah = charger->bat_charge_full_design_uah / 1000;
788 * Set battery as "set up". BSP driver uses this value even
789 * though datasheet claims it's a read-only value.
791 regmap_write_bits(rk808->regmap, RK817_GAS_GAUGE_GG_STS,
793 /* Save nvram values */
794 ret = rk817_record_battery_nvram_values(charger);
798 ret = rk817_read_battery_nvram_values(charger);
802 regmap_bulk_read(rk808->regmap, RK817_GAS_GAUGE_Q_PRES_H3,
804 tmp = get_unaligned_be32(bulk_reg);
807 boot_charge_mah = ADC_TO_CHARGE_UAH(tmp,
808 charger->res_div) / 1000;
810 * Check if the columb counter has been off for more than 30
811 * minutes as it tends to drift downward. If so, re-init soc
812 * with the boot voltage instead. Note the unit values for the
813 * OFF_CNT register appear to be in decaminutes and stops
814 * counting at 2550 (0xFF) minutes. BSP kernel used OCV, but
815 * for me occasionally that would show invalid values. Boot
816 * voltage is only accurate for me on first poweron (not
817 * reboots), but we shouldn't ever encounter an OFF_CNT more
818 * than 0 on a reboot anyway.
820 regmap_read(rk808->regmap, RK817_GAS_GAUGE_OFF_CNT, &off_time);
822 regmap_bulk_read(rk808->regmap,
823 RK817_GAS_GAUGE_PWRON_VOL_H,
825 tmp = get_unaligned_be16(bulk_reg);
826 boot_voltage = (charger->voltage_k * tmp) +
827 1000 * charger->voltage_b;
829 power_supply_batinfo_ocv2cap(bat_info,
833 charger->soc = (boot_charge_mah * 1000 * 100 /
839 * Now we have our full charge capacity and soc, init the columb
842 boot_charge_mah = charger->soc * charger->fcc_mah / 100 / 1000;
843 if (boot_charge_mah > charger->fcc_mah)
844 boot_charge_mah = charger->fcc_mah;
845 tmp = CHARGE_TO_ADC(boot_charge_mah, charger->res_div);
846 put_unaligned_be32(tmp, bulk_reg);
847 ret = regmap_bulk_write(rk808->regmap, RK817_GAS_GAUGE_Q_INIT_H3,
852 /* Set QMAX value to max design capacity. */
853 tmp = CHARGE_TO_ADC((charger->bat_charge_full_design_uah / 1000),
855 put_unaligned_be32(tmp, bulk_reg);
856 ret = regmap_bulk_write(rk808->regmap, RK817_GAS_GAUGE_Q_MAX_H3,
864 static int rk817_battery_init(struct rk817_charger *charger,
865 struct power_supply_battery_info *bat_info)
867 struct rk808 *rk808 = charger->rk808;
868 u32 tmp, max_chg_vol_mv, max_chg_cur_ma;
869 u8 max_chg_vol_reg, chg_term_i_reg;
870 int ret, chg_term_ma, max_chg_cur_reg;
873 /* Get initial plug state */
874 regmap_read(rk808->regmap, RK817_SYS_STS, &tmp);
875 charger->plugged_in = (tmp & RK817_PLUG_IN_STS);
878 * Turn on all ADC functions to measure battery, USB, and sys voltage,
879 * as well as batt temp. Note only tested implementation so far does
880 * not use a battery with a thermistor.
882 regmap_write(rk808->regmap, RK817_GAS_GAUGE_ADC_CONFIG0, 0xfc);
885 * Set relax mode voltage sampling interval and ADC offset calibration
886 * interval to 8 minutes to mirror BSP kernel. Set voltage and current
887 * modes to average to mirror BSP kernel.
889 regmap_write(rk808->regmap, RK817_GAS_GAUGE_GG_CON, 0x04);
891 /* Calibrate voltage like the BSP does here. */
892 rk817_bat_calib_vol(charger);
894 /* Write relax threshold, derived from sleep enter current. */
895 tmp = CURRENT_TO_ADC(charger->sleep_enter_current_ua,
897 put_unaligned_be16(tmp, bulk_reg);
898 regmap_bulk_write(rk808->regmap, RK817_GAS_GAUGE_RELAX_THRE_H,
901 /* Write sleep sample current, derived from sleep filter current. */
902 tmp = CURRENT_TO_ADC(charger->sleep_filter_current_ua,
904 put_unaligned_be16(tmp, bulk_reg);
905 regmap_bulk_write(rk808->regmap, RK817_GAS_GAUGE_SLEEP_CON_SAMP_CUR_H,
908 /* Restart battery relax voltage */
909 regmap_write_bits(rk808->regmap, RK817_GAS_GAUGE_GG_STS,
910 RK817_RELAX_VOL_UPD, (0x0 << 2));
913 * Set OCV Threshold Voltage to 127.5mV. This was hard coded like this
916 regmap_write(rk808->regmap, RK817_GAS_GAUGE_OCV_THRE_VOL, 0xff);
919 * Set maximum charging voltage to battery max voltage. Trying to be
920 * incredibly safe with these value, as setting them wrong could
921 * overcharge the battery, which would be very bad.
923 max_chg_vol_mv = bat_info->constant_charge_voltage_max_uv / 1000;
924 max_chg_cur_ma = bat_info->constant_charge_current_max_ua / 1000;
926 if (max_chg_vol_mv < 4100) {
927 return dev_err_probe(charger->dev, -EINVAL,
928 "invalid max charger voltage, value %u unsupported\n",
929 max_chg_vol_mv * 1000);
931 if (max_chg_vol_mv > 4450) {
932 dev_info(charger->dev,
933 "Setting max charge voltage to 4450000uv\n");
934 max_chg_vol_mv = 4450;
937 if (max_chg_cur_ma < 500) {
938 return dev_err_probe(charger->dev, -EINVAL,
939 "invalid max charger current, value %u unsupported\n",
940 max_chg_cur_ma * 1000);
942 if (max_chg_cur_ma > 3500)
943 dev_info(charger->dev,
944 "Setting max charge current to 3500000ua\n");
947 * Now that the values are sanity checked, if we subtract 4100 from the
948 * max voltage and divide by 50, we conviently get the exact value for
949 * the registers, which are 4.1v, 4.15v, 4.2v, 4.25v, 4.3v, 4.35v,
950 * 4.4v, and 4.45v; these correspond to values 0x00 through 0x07.
952 max_chg_vol_reg = (max_chg_vol_mv - 4100) / 50;
954 max_chg_cur_reg = rk817_chg_cur_to_reg(max_chg_cur_ma);
956 if (max_chg_vol_reg < 0 || max_chg_vol_reg > 7) {
957 return dev_err_probe(charger->dev, -EINVAL,
958 "invalid max charger voltage, value %u unsupported\n",
959 max_chg_vol_mv * 1000);
961 if (max_chg_cur_reg < 0 || max_chg_cur_reg > 7) {
962 return dev_err_probe(charger->dev, -EINVAL,
963 "invalid max charger current, value %u unsupported\n",
964 max_chg_cur_ma * 1000);
968 * Write the values to the registers, and deliver an emergency warning
969 * in the event they are not written correctly.
971 ret = regmap_write_bits(rk808->regmap, RK817_PMIC_CHRG_OUT,
972 RK817_CHRG_VOL_SEL, (max_chg_vol_reg << 4));
974 dev_emerg(charger->dev,
975 "Danger, unable to set max charger voltage: %u\n",
979 ret = regmap_write_bits(rk808->regmap, RK817_PMIC_CHRG_OUT,
980 RK817_CHRG_CUR_SEL, max_chg_cur_reg);
982 dev_emerg(charger->dev,
983 "Danger, unable to set max charger current: %u\n",
987 /* Set charge finishing mode to analog */
988 regmap_write_bits(rk808->regmap, RK817_PMIC_CHRG_TERM,
989 RK817_CHRG_TERM_ANA_DIG, (0x0 << 2));
992 * Set charge finish current, warn if value not in range and keep
995 chg_term_ma = bat_info->charge_term_current_ua / 1000;
996 if (chg_term_ma < 150 || chg_term_ma > 400) {
997 dev_warn(charger->dev,
998 "Invalid charge termination %u, keeping default\n",
1004 * Values of 150ma, 200ma, 300ma, and 400ma correspond to 00, 01, 10,
1007 chg_term_i_reg = (chg_term_ma - 100) / 100;
1008 regmap_write_bits(rk808->regmap, RK817_PMIC_CHRG_TERM,
1009 RK817_CHRG_TERM_ANA_SEL, chg_term_i_reg);
1011 ret = rk817_read_or_set_full_charge_on_boot(charger, bat_info);
1016 * Set minimum USB input voltage to 4.5v and enable USB voltage input
1019 regmap_write_bits(rk808->regmap, RK817_PMIC_CHRG_IN,
1020 RK817_USB_VLIM_SEL, (0x05 << 4));
1021 regmap_write_bits(rk808->regmap, RK817_PMIC_CHRG_IN, RK817_USB_VLIM_EN,
1025 * Set average USB input current limit to 1.5A and enable USB current
1028 regmap_write_bits(rk808->regmap, RK817_PMIC_CHRG_IN,
1029 RK817_USB_ILIM_SEL, 0x03);
1030 regmap_write_bits(rk808->regmap, RK817_PMIC_CHRG_IN, RK817_USB_ILIM_EN,
1036 static void rk817_charging_monitor(struct work_struct *work)
1038 struct rk817_charger *charger;
1040 charger = container_of(work, struct rk817_charger, work.work);
1042 rk817_read_props(charger);
1044 /* Run every 8 seconds like the BSP driver did. */
1045 queue_delayed_work(system_wq, &charger->work, msecs_to_jiffies(8000));
1048 static int rk817_charger_probe(struct platform_device *pdev)
1050 struct rk808 *rk808 = dev_get_drvdata(pdev->dev.parent);
1051 struct rk817_charger *charger;
1052 struct device_node *node;
1053 struct power_supply_battery_info *bat_info;
1054 struct device *dev = &pdev->dev;
1055 struct power_supply_config pscfg = {};
1056 int plugin_irq, plugout_irq;
1060 node = of_get_child_by_name(dev->parent->of_node, "charger");
1064 charger = devm_kzalloc(&pdev->dev, sizeof(*charger), GFP_KERNEL);
1070 charger->rk808 = rk808;
1072 charger->dev = &pdev->dev;
1073 platform_set_drvdata(pdev, charger);
1075 rk817_bat_calib_vol(charger);
1077 pscfg.drv_data = charger;
1078 pscfg.of_node = node;
1081 * Get sample resistor value. Note only values of 10000 or 20000
1082 * microohms are allowed. Schematic for my test implementation (an
1083 * Odroid Go Advance) shows a 10 milliohm resistor for reference.
1085 ret = of_property_read_u32(node, "rockchip,resistor-sense-micro-ohms",
1088 return dev_err_probe(dev, ret,
1089 "Error reading sample resistor value\n");
1092 * Store as a 1 or a 2, since all we really use the value for is as a
1093 * divisor in some calculations.
1095 charger->res_div = (of_value == 20000) ? 2 : 1;
1098 * Get sleep enter current value. Not sure what this value is for
1099 * other than to help calibrate the relax threshold.
1101 ret = of_property_read_u32(node,
1102 "rockchip,sleep-enter-current-microamp",
1105 return dev_err_probe(dev, ret,
1106 "Error reading sleep enter cur value\n");
1108 charger->sleep_enter_current_ua = of_value;
1110 /* Get sleep filter current value */
1111 ret = of_property_read_u32(node,
1112 "rockchip,sleep-filter-current-microamp",
1115 return dev_err_probe(dev, ret,
1116 "Error reading sleep filter cur value\n");
1119 charger->sleep_filter_current_ua = of_value;
1121 charger->bat_ps = devm_power_supply_register(&pdev->dev,
1122 &rk817_bat_desc, &pscfg);
1123 if (IS_ERR(charger->bat_ps))
1124 return dev_err_probe(dev, -EINVAL,
1125 "Battery failed to probe\n");
1127 charger->chg_ps = devm_power_supply_register(&pdev->dev,
1128 &rk817_chg_desc, &pscfg);
1129 if (IS_ERR(charger->chg_ps))
1130 return dev_err_probe(dev, -EINVAL,
1131 "Charger failed to probe\n");
1133 ret = power_supply_get_battery_info(charger->bat_ps,
1136 return dev_err_probe(dev, ret,
1137 "Unable to get battery info\n");
1140 if ((bat_info->charge_full_design_uah <= 0) ||
1141 (bat_info->voltage_min_design_uv <= 0) ||
1142 (bat_info->voltage_max_design_uv <= 0) ||
1143 (bat_info->constant_charge_voltage_max_uv <= 0) ||
1144 (bat_info->constant_charge_current_max_ua <= 0) ||
1145 (bat_info->charge_term_current_ua <= 0)) {
1146 return dev_err_probe(dev, -EINVAL,
1147 "Required bat info missing or invalid\n");
1150 charger->bat_charge_full_design_uah = bat_info->charge_full_design_uah;
1151 charger->bat_voltage_min_design_uv = bat_info->voltage_min_design_uv;
1152 charger->bat_voltage_max_design_uv = bat_info->voltage_max_design_uv;
1155 * Has to run after power_supply_get_battery_info as it depends on some
1156 * values discovered from that routine.
1158 ret = rk817_battery_init(charger, bat_info);
1162 power_supply_put_battery_info(charger->bat_ps, bat_info);
1164 plugin_irq = platform_get_irq(pdev, 0);
1168 plugout_irq = platform_get_irq(pdev, 1);
1169 if (plugout_irq < 0)
1172 ret = devm_request_threaded_irq(charger->dev, plugin_irq, NULL,
1174 IRQF_TRIGGER_RISING | IRQF_ONESHOT,
1175 "rk817_plug_in", charger);
1177 return dev_err_probe(&pdev->dev, ret,
1178 "plug_in_irq request failed!\n");
1181 ret = devm_request_threaded_irq(charger->dev, plugout_irq, NULL,
1183 IRQF_TRIGGER_RISING | IRQF_ONESHOT,
1184 "rk817_plug_out", charger);
1186 return dev_err_probe(&pdev->dev, ret,
1187 "plug_out_irq request failed!\n");
1190 ret = devm_delayed_work_autocancel(&pdev->dev, &charger->work,
1191 rk817_charging_monitor);
1195 /* Force the first update immediately. */
1196 mod_delayed_work(system_wq, &charger->work, 0);
1202 static struct platform_driver rk817_charger_driver = {
1203 .probe = rk817_charger_probe,
1205 .name = "rk817-charger",
1208 module_platform_driver(rk817_charger_driver);
1210 MODULE_DESCRIPTION("Battery power supply driver for RK817 PMIC");
1211 MODULE_AUTHOR("Maya Matuszczyk <maccraft123mc@gmail.com>");
1212 MODULE_AUTHOR("Chris Morgan <macromorgan@hotmail.com>");
1213 MODULE_LICENSE("GPL");