--- /dev/null
+// SPDX-License-Identifier: GPL-2.0+
+/*
+ * Charger Driver for Rockchip rk817
+ *
+ * Copyright (c) 2021 Maya Matuszczyk <maccraft123mc@gmail.com>
+ *
+ * Authors: Maya Matuszczyk <maccraft123mc@gmail.com>
+ * Chris Morgan <macromorgan@hotmail.com>
+ */
+
+#include <asm/unaligned.h>
+#include <linux/devm-helpers.h>
+#include <linux/mfd/rk808.h>
+#include <linux/irq.h>
+#include <linux/of.h>
+#include <linux/platform_device.h>
+#include <linux/power_supply.h>
+#include <linux/regmap.h>
+
+/* Charging statuses reported by hardware register */
+enum rk817_charge_status {
+ CHRG_OFF,
+ DEAD_CHRG,
+ TRICKLE_CHRG,
+ CC_OR_CV_CHRG,
+ CHARGE_FINISH,
+ USB_OVER_VOL,
+ BAT_TMP_ERR,
+ BAT_TIM_ERR,
+};
+
+/*
+ * Max charging current read to/written from hardware register.
+ * Note how highest value corresponding to 0x7 is the lowest
+ * current, this is per the datasheet.
+ */
+enum rk817_chg_cur {
+ CHG_1A,
+ CHG_1_5A,
+ CHG_2A,
+ CHG_2_5A,
+ CHG_2_75A,
+ CHG_3A,
+ CHG_3_5A,
+ CHG_0_5A,
+};
+
+struct rk817_charger {
+ struct device *dev;
+ struct rk808 *rk808;
+
+ struct power_supply *bat_ps;
+ struct power_supply *chg_ps;
+ bool plugged_in;
+ bool battery_present;
+
+ /*
+ * voltage_k and voltage_b values are used to calibrate the ADC
+ * voltage readings. While they are documented in the BSP kernel and
+ * datasheet as voltage_k and voltage_b, there is no further
+ * information explaining them in more detail.
+ */
+
+ uint32_t voltage_k;
+ uint32_t voltage_b;
+
+ /*
+ * soc - state of charge - like the BSP this is stored as a percentage,
+ * to the thousandth. BSP has a display state of charge (dsoc) and a
+ * remaining state of charge (rsoc). This value will be used for both
+ * purposes here so we don't do any fancy math to try and "smooth" the
+ * charge and just report it as it is. Note for example an soc of 100
+ * is stored as 100000, an soc of 50 is stored as 50000, etc.
+ */
+ int soc;
+
+ /*
+ * Capacity of battery when fully charged, equal or less than design
+ * capacity depending upon wear. BSP kernel saves to nvram in mAh,
+ * so this value is in mAh not the standard uAh.
+ */
+ int fcc_mah;
+
+ /*
+ * Calibrate the SOC on a fully charged battery, this way we can use
+ * the calibrated SOC value to correct for columb counter drift.
+ */
+ bool soc_cal;
+
+ /* Implementation specific immutable properties from device tree */
+ int res_div;
+ int sleep_enter_current_ua;
+ int sleep_filter_current_ua;
+ int bat_charge_full_design_uah;
+ int bat_voltage_min_design_uv;
+ int bat_voltage_max_design_uv;
+
+ /* Values updated periodically by driver for display. */
+ int charge_now_uah;
+ int volt_avg_uv;
+ int cur_avg_ua;
+ int max_chg_cur_ua;
+ int max_chg_volt_uv;
+ int charge_status;
+ int charger_input_volt_avg_uv;
+
+ /* Work queue to periodically update values. */
+ struct delayed_work work;
+};
+
+/* ADC coefficients extracted from BSP kernel */
+#define ADC_TO_CURRENT(adc_value, res_div) \
+ (adc_value * 172 / res_div)
+
+#define CURRENT_TO_ADC(current, samp_res) \
+ (current * samp_res / 172)
+
+#define CHARGE_TO_ADC(capacity, res_div) \
+ (capacity * res_div * 3600 / 172 * 1000)
+
+#define ADC_TO_CHARGE_UAH(adc_value, res_div) \
+ (adc_value / 3600 * 172 / res_div)
+
+static u8 rk817_chg_cur_to_reg(u32 chg_cur_ma)
+{
+ if (chg_cur_ma >= 3500)
+ return CHG_3_5A;
+ else if (chg_cur_ma >= 3000)
+ return CHG_3A;
+ else if (chg_cur_ma >= 2750)
+ return CHG_2_75A;
+ else if (chg_cur_ma >= 2500)
+ return CHG_2_5A;
+ else if (chg_cur_ma >= 2000)
+ return CHG_2A;
+ else if (chg_cur_ma >= 1500)
+ return CHG_1_5A;
+ else if (chg_cur_ma >= 1000)
+ return CHG_1A;
+ else if (chg_cur_ma >= 500)
+ return CHG_0_5A;
+ else
+ return -EINVAL;
+}
+
+static int rk817_chg_cur_from_reg(u8 reg)
+{
+ switch (reg) {
+ case CHG_0_5A:
+ return 500000;
+ case CHG_1A:
+ return 1000000;
+ case CHG_1_5A:
+ return 1500000;
+ case CHG_2A:
+ return 2000000;
+ case CHG_2_5A:
+ return 2500000;
+ case CHG_2_75A:
+ return 2750000;
+ case CHG_3A:
+ return 3000000;
+ case CHG_3_5A:
+ return 3500000;
+ default:
+ return -EINVAL;
+ }
+}
+
+static void rk817_bat_calib_vol(struct rk817_charger *charger)
+{
+ uint32_t vcalib0 = 0;
+ uint32_t vcalib1 = 0;
+ u8 bulk_reg[2];
+
+ /* calibrate voltage */
+ regmap_bulk_read(charger->rk808->regmap, RK817_GAS_GAUGE_VCALIB0_H,
+ bulk_reg, 2);
+ vcalib0 = get_unaligned_be16(bulk_reg);
+
+ regmap_bulk_read(charger->rk808->regmap, RK817_GAS_GAUGE_VCALIB1_H,
+ bulk_reg, 2);
+ vcalib1 = get_unaligned_be16(bulk_reg);
+
+ /* values were taken from BSP kernel */
+ charger->voltage_k = (4025 - 2300) * 1000 /
+ ((vcalib1 - vcalib0) ? (vcalib1 - vcalib0) : 1);
+ charger->voltage_b = 4025 - (charger->voltage_k * vcalib1) / 1000;
+}
+
+static void rk817_bat_calib_cur(struct rk817_charger *charger)
+{
+ u8 bulk_reg[2];
+
+ /* calibrate current */
+ regmap_bulk_read(charger->rk808->regmap, RK817_GAS_GAUGE_IOFFSET_H,
+ bulk_reg, 2);
+ regmap_bulk_write(charger->rk808->regmap, RK817_GAS_GAUGE_CAL_OFFSET_H,
+ bulk_reg, 2);
+}
+
+/*
+ * note that only the fcc_mah is really used by this driver, the other values
+ * are to ensure we can remain backwards compatible with the BSP kernel.
+ */
+static int rk817_record_battery_nvram_values(struct rk817_charger *charger)
+{
+ u8 bulk_reg[3];
+ int ret, rsoc;
+
+ /*
+ * write the soc value to the nvram location used by the BSP kernel
+ * for the dsoc value.
+ */
+ put_unaligned_le24(charger->soc, bulk_reg);
+ ret = regmap_bulk_write(charger->rk808->regmap, RK817_GAS_GAUGE_BAT_R1,
+ bulk_reg, 3);
+ if (ret < 0)
+ return ret;
+ /*
+ * write the remaining capacity in mah to the nvram location used by
+ * the BSP kernel for the rsoc value.
+ */
+ rsoc = (charger->soc * charger->fcc_mah) / 100000;
+ put_unaligned_le24(rsoc, bulk_reg);
+ ret = regmap_bulk_write(charger->rk808->regmap, RK817_GAS_GAUGE_DATA0,
+ bulk_reg, 3);
+ if (ret < 0)
+ return ret;
+ /* write the fcc_mah in mAh, just as the BSP kernel does. */
+ put_unaligned_le24(charger->fcc_mah, bulk_reg);
+ ret = regmap_bulk_write(charger->rk808->regmap, RK817_GAS_GAUGE_DATA3,
+ bulk_reg, 3);
+ if (ret < 0)
+ return ret;
+
+ return 0;
+}
+
+static int rk817_bat_calib_cap(struct rk817_charger *charger)
+{
+ struct rk808 *rk808 = charger->rk808;
+ int tmp, charge_now, charge_now_adc, volt_avg;
+ u8 bulk_reg[4];
+
+ /* Calibrate the soc and fcc on a fully charged battery */
+
+ if (charger->charge_status == CHARGE_FINISH && (!charger->soc_cal)) {
+ /*
+ * soc should be 100000 and columb counter should show the full
+ * charge capacity. Note that if the device is unplugged for a
+ * period of several days the columb counter will have a large
+ * margin of error, so setting it back to the full charge on
+ * a completed charge cycle should correct this (my device was
+ * showing 33% battery after 3 days unplugged when it should
+ * have been closer to 95% based on voltage and charge
+ * current).
+ */
+
+ charger->soc = 100000;
+ charge_now_adc = CHARGE_TO_ADC(charger->fcc_mah,
+ charger->res_div);
+ put_unaligned_be32(charge_now_adc, bulk_reg);
+ regmap_bulk_write(rk808->regmap, RK817_GAS_GAUGE_Q_INIT_H3,
+ bulk_reg, 4);
+
+ charger->soc_cal = 1;
+ dev_dbg(charger->dev,
+ "Fully charged. SOC is %d, full capacity is %d\n",
+ charger->soc, charger->fcc_mah * 1000);
+ }
+
+ /*
+ * The columb counter can drift up slightly, so we should correct for
+ * it. But don't correct it until we're at 100% soc.
+ */
+ if (charger->charge_status == CHARGE_FINISH && charger->soc_cal) {
+ regmap_bulk_read(rk808->regmap, RK817_GAS_GAUGE_Q_PRES_H3,
+ bulk_reg, 4);
+ charge_now_adc = get_unaligned_be32(bulk_reg);
+ if (charge_now_adc < 0)
+ return charge_now_adc;
+ charge_now = ADC_TO_CHARGE_UAH(charge_now_adc,
+ charger->res_div);
+
+ /*
+ * Re-init columb counter with updated values to correct drift.
+ */
+ if (charge_now / 1000 > charger->fcc_mah) {
+ dev_dbg(charger->dev,
+ "Recalibrating columb counter to %d uah\n",
+ charge_now);
+ /*
+ * Order of operations matters here to ensure we keep
+ * enough precision until the last step to keep from
+ * making needless updates to columb counter.
+ */
+ charge_now_adc = CHARGE_TO_ADC(charger->fcc_mah,
+ charger->res_div);
+ put_unaligned_be32(charge_now_adc, bulk_reg);
+ regmap_bulk_write(rk808->regmap,
+ RK817_GAS_GAUGE_Q_INIT_H3,
+ bulk_reg, 4);
+ }
+ }
+
+ /*
+ * Calibrate the fully charged capacity when we previously had a full
+ * battery (soc_cal = 1) and are now empty (at or below minimum design
+ * voltage). If our columb counter is still positive, subtract that
+ * from our fcc value to get a calibrated fcc, and if our columb
+ * counter is negative add that to our fcc (but not to exceed our
+ * design capacity).
+ */
+ regmap_bulk_read(charger->rk808->regmap, RK817_GAS_GAUGE_BAT_VOL_H,
+ bulk_reg, 2);
+ tmp = get_unaligned_be16(bulk_reg);
+ volt_avg = (charger->voltage_k * tmp) + 1000 * charger->voltage_b;
+ if (volt_avg <= charger->bat_voltage_min_design_uv &&
+ charger->soc_cal) {
+ regmap_bulk_read(rk808->regmap, RK817_GAS_GAUGE_Q_PRES_H3,
+ bulk_reg, 4);
+ charge_now_adc = get_unaligned_be32(bulk_reg);
+ charge_now = ADC_TO_CHARGE_UAH(charge_now_adc,
+ charger->res_div);
+ /*
+ * Note, if charge_now is negative this will add it (what we
+ * want) and if it's positive this will subtract (also what
+ * we want).
+ */
+ charger->fcc_mah = charger->fcc_mah - (charge_now / 1000);
+
+ dev_dbg(charger->dev,
+ "Recalibrating full charge capacity to %d uah\n",
+ charger->fcc_mah * 1000);
+ }
+
+ rk817_record_battery_nvram_values(charger);
+
+ return 0;
+}
+
+static void rk817_read_props(struct rk817_charger *charger)
+{
+ int tmp, reg;
+ u8 bulk_reg[4];
+
+ /*
+ * Recalibrate voltage and current readings if we need to BSP does both
+ * on CUR_CALIB_UPD, ignoring VOL_CALIB_UPD. Curiously enough, both
+ * documentation and the BSP show that you perform an update if bit 7
+ * is 1, but you clear the status by writing a 1 to bit 7.
+ */
+ regmap_read(charger->rk808->regmap, RK817_GAS_GAUGE_ADC_CONFIG1, ®);
+ if (reg & RK817_VOL_CUR_CALIB_UPD) {
+ rk817_bat_calib_cur(charger);
+ rk817_bat_calib_vol(charger);
+ regmap_write_bits(charger->rk808->regmap,
+ RK817_GAS_GAUGE_ADC_CONFIG1,
+ RK817_VOL_CUR_CALIB_UPD,
+ RK817_VOL_CUR_CALIB_UPD);
+ }
+
+ /* Update reported charge. */
+ regmap_bulk_read(charger->rk808->regmap, RK817_GAS_GAUGE_Q_PRES_H3,
+ bulk_reg, 4);
+ tmp = get_unaligned_be32(bulk_reg);
+ charger->charge_now_uah = ADC_TO_CHARGE_UAH(tmp, charger->res_div);
+ if (charger->charge_now_uah < 0)
+ charger->charge_now_uah = 0;
+ if (charger->charge_now_uah > charger->fcc_mah * 1000)
+ charger->charge_now_uah = charger->fcc_mah * 1000;
+
+ /* Update soc based on reported charge. */
+ charger->soc = charger->charge_now_uah * 100 / charger->fcc_mah;
+
+ /* Update reported voltage. */
+ regmap_bulk_read(charger->rk808->regmap, RK817_GAS_GAUGE_BAT_VOL_H,
+ bulk_reg, 2);
+ tmp = get_unaligned_be16(bulk_reg);
+ charger->volt_avg_uv = (charger->voltage_k * tmp) + 1000 *
+ charger->voltage_b;
+
+ /*
+ * Update reported current. Note value from registers is a signed 16
+ * bit int.
+ */
+ regmap_bulk_read(charger->rk808->regmap, RK817_GAS_GAUGE_BAT_CUR_H,
+ bulk_reg, 2);
+ tmp = (short int)get_unaligned_be16(bulk_reg);
+ charger->cur_avg_ua = ADC_TO_CURRENT(tmp, charger->res_div);
+
+ /*
+ * Update the max charge current. This value shouldn't change, but we
+ * can read it to report what the PMIC says it is instead of simply
+ * returning the default value.
+ */
+ regmap_read(charger->rk808->regmap, RK817_PMIC_CHRG_OUT, ®);
+ charger->max_chg_cur_ua =
+ rk817_chg_cur_from_reg(reg & RK817_CHRG_CUR_SEL);
+
+ /*
+ * Update max charge voltage. Like the max charge current this value
+ * shouldn't change, but we can report what the PMIC says.
+ */
+ regmap_read(charger->rk808->regmap, RK817_PMIC_CHRG_OUT, ®);
+ charger->max_chg_volt_uv = ((((reg & RK817_CHRG_VOL_SEL) >> 4) *
+ 50000) + 4100000);
+
+ /* Check if battery still present. */
+ regmap_read(charger->rk808->regmap, RK817_PMIC_CHRG_STS, ®);
+ charger->battery_present = (reg & RK817_BAT_EXS);
+
+ /* Get which type of charge we are using (if any). */
+ regmap_read(charger->rk808->regmap, RK817_PMIC_CHRG_STS, ®);
+ charger->charge_status = (reg >> 4) & 0x07;
+
+ /*
+ * Get charger input voltage. Note that on my example hardware (an
+ * Odroid Go Advance) the voltage of the power connector is measured
+ * on the register labelled USB in the datasheet; I don't know if this
+ * is how it is designed or just a quirk of the implementation. I
+ * believe this will also measure the voltage of the USB output when in
+ * OTG mode, if that is the case we may need to change this in the
+ * future to return 0 if the power supply status is offline (I can't
+ * test this with my current implementation. Also, when the voltage
+ * should be zero sometimes the ADC still shows a single bit (which
+ * would register as 20000uv). When this happens set it to 0.
+ */
+ regmap_bulk_read(charger->rk808->regmap, RK817_GAS_GAUGE_USB_VOL_H,
+ bulk_reg, 2);
+ reg = get_unaligned_be16(bulk_reg);
+ if (reg > 1) {
+ tmp = ((charger->voltage_k * reg / 1000 + charger->voltage_b) *
+ 60 / 46);
+ charger->charger_input_volt_avg_uv = tmp * 1000;
+ } else {
+ charger->charger_input_volt_avg_uv = 0;
+ }
+
+ /* Calibrate battery capacity and soc. */
+ rk817_bat_calib_cap(charger);
+}
+
+static int rk817_bat_get_prop(struct power_supply *ps,
+ enum power_supply_property prop,
+ union power_supply_propval *val)
+{
+ struct rk817_charger *charger = power_supply_get_drvdata(ps);
+
+ switch (prop) {
+ case POWER_SUPPLY_PROP_PRESENT:
+ val->intval = charger->battery_present;
+ break;
+ case POWER_SUPPLY_PROP_STATUS:
+ if (charger->cur_avg_ua < 0) {
+ val->intval = POWER_SUPPLY_STATUS_DISCHARGING;
+ break;
+ }
+ switch (charger->charge_status) {
+ case CHRG_OFF:
+ val->intval = POWER_SUPPLY_STATUS_NOT_CHARGING;
+ break;
+ /*
+ * Dead charge is documented, but not explained. I never
+ * observed it but assume it's a pre-charge for a dead
+ * battery.
+ */
+ case DEAD_CHRG:
+ case TRICKLE_CHRG:
+ case CC_OR_CV_CHRG:
+ val->intval = POWER_SUPPLY_STATUS_CHARGING;
+ break;
+ case CHARGE_FINISH:
+ val->intval = POWER_SUPPLY_STATUS_FULL;
+ break;
+ default:
+ val->intval = POWER_SUPPLY_STATUS_UNKNOWN;
+ return -EINVAL;
+
+ }
+ break;
+ case POWER_SUPPLY_PROP_CHARGE_TYPE:
+ switch (charger->charge_status) {
+ case CHRG_OFF:
+ case CHARGE_FINISH:
+ val->intval = POWER_SUPPLY_CHARGE_TYPE_NONE;
+ break;
+ case TRICKLE_CHRG:
+ val->intval = POWER_SUPPLY_CHARGE_TYPE_TRICKLE;
+ break;
+ case DEAD_CHRG:
+ case CC_OR_CV_CHRG:
+ val->intval = POWER_SUPPLY_CHARGE_TYPE_STANDARD;
+ break;
+ default:
+ val->intval = POWER_SUPPLY_CHARGE_TYPE_UNKNOWN;
+ break;
+ }
+ break;
+ case POWER_SUPPLY_PROP_CHARGE_FULL:
+ val->intval = charger->fcc_mah * 1000;
+ break;
+ case POWER_SUPPLY_PROP_CHARGE_FULL_DESIGN:
+ val->intval = charger->bat_charge_full_design_uah;
+ break;
+ case POWER_SUPPLY_PROP_CHARGE_EMPTY_DESIGN:
+ val->intval = 0;
+ break;
+ case POWER_SUPPLY_PROP_CHARGE_NOW:
+ val->intval = charger->charge_now_uah;
+ break;
+ case POWER_SUPPLY_PROP_VOLTAGE_MIN_DESIGN:
+ val->intval = charger->bat_voltage_min_design_uv;
+ break;
+ case POWER_SUPPLY_PROP_CAPACITY:
+ /* Add 500 so that values like 99999 are 100% not 99%. */
+ val->intval = (charger->soc + 500) / 1000;
+ if (val->intval > 100)
+ val->intval = 100;
+ if (val->intval < 0)
+ val->intval = 0;
+ break;
+ case POWER_SUPPLY_PROP_VOLTAGE_AVG:
+ val->intval = charger->volt_avg_uv;
+ break;
+ case POWER_SUPPLY_PROP_CURRENT_AVG:
+ val->intval = charger->cur_avg_ua;
+ break;
+ case POWER_SUPPLY_PROP_CONSTANT_CHARGE_CURRENT_MAX:
+ val->intval = charger->max_chg_cur_ua;
+ break;
+ case POWER_SUPPLY_PROP_CONSTANT_CHARGE_VOLTAGE_MAX:
+ val->intval = charger->max_chg_volt_uv;
+ break;
+ case POWER_SUPPLY_PROP_VOLTAGE_MAX_DESIGN:
+ val->intval = charger->bat_voltage_max_design_uv;
+ break;
+ default:
+ return -EINVAL;
+ }
+ return 0;
+}
+
+static int rk817_chg_get_prop(struct power_supply *ps,
+ enum power_supply_property prop,
+ union power_supply_propval *val)
+{
+ struct rk817_charger *charger = power_supply_get_drvdata(ps);
+
+ switch (prop) {
+ case POWER_SUPPLY_PROP_ONLINE:
+ val->intval = charger->plugged_in;
+ break;
+ case POWER_SUPPLY_PROP_VOLTAGE_MAX_DESIGN:
+ /* max voltage from datasheet at 5.5v (default 5.0v) */
+ val->intval = 5500000;
+ break;
+ case POWER_SUPPLY_PROP_VOLTAGE_MIN_DESIGN:
+ /* min voltage from datasheet at 3.8v (default 5.0v) */
+ val->intval = 3800000;
+ break;
+ case POWER_SUPPLY_PROP_VOLTAGE_AVG:
+ val->intval = charger->charger_input_volt_avg_uv;
+ break;
+ /*
+ * While it's possible that other implementations could use different
+ * USB types, the current implementation for this PMIC (the Odroid Go
+ * Advance) only uses a dedicated charging port with no rx/tx lines.
+ */
+ case POWER_SUPPLY_PROP_USB_TYPE:
+ val->intval = POWER_SUPPLY_USB_TYPE_DCP;
+ break;
+ default:
+ return -EINVAL;
+ }
+ return 0;
+
+}
+
+static irqreturn_t rk817_plug_in_isr(int irq, void *cg)
+{
+ struct rk817_charger *charger;
+
+ charger = (struct rk817_charger *)cg;
+ charger->plugged_in = 1;
+ power_supply_changed(charger->chg_ps);
+ power_supply_changed(charger->bat_ps);
+ /* try to recalibrate capacity if we hit full charge. */
+ charger->soc_cal = 0;
+
+ rk817_read_props(charger);
+
+ dev_dbg(charger->dev, "Power Cord Inserted\n");
+
+ return IRQ_HANDLED;
+}
+
+static irqreturn_t rk817_plug_out_isr(int irq, void *cg)
+{
+ struct rk817_charger *charger;
+ struct rk808 *rk808;
+
+ charger = (struct rk817_charger *)cg;
+ rk808 = charger->rk808;
+ charger->plugged_in = 0;
+ power_supply_changed(charger->bat_ps);
+ power_supply_changed(charger->chg_ps);
+
+ /*
+ * For some reason the bits of RK817_PMIC_CHRG_IN reset whenever the
+ * power cord is unplugged. This was not documented in the BSP kernel
+ * or the datasheet and only discovered by trial and error. Set minimum
+ * USB input voltage to 4.5v and enable USB voltage input limit.
+ */
+ regmap_write_bits(rk808->regmap, RK817_PMIC_CHRG_IN,
+ RK817_USB_VLIM_SEL, (0x05 << 4));
+ regmap_write_bits(rk808->regmap, RK817_PMIC_CHRG_IN, RK817_USB_VLIM_EN,
+ (0x01 << 7));
+
+ /*
+ * Set average USB input current limit to 1.5A and enable USB current
+ * input limit.
+ */
+ regmap_write_bits(rk808->regmap, RK817_PMIC_CHRG_IN,
+ RK817_USB_ILIM_SEL, 0x03);
+ regmap_write_bits(rk808->regmap, RK817_PMIC_CHRG_IN, RK817_USB_ILIM_EN,
+ (0x01 << 3));
+
+ rk817_read_props(charger);
+
+ dev_dbg(charger->dev, "Power Cord Removed\n");
+
+ return IRQ_HANDLED;
+}
+
+static enum power_supply_property rk817_bat_props[] = {
+ POWER_SUPPLY_PROP_PRESENT,
+ POWER_SUPPLY_PROP_STATUS,
+ POWER_SUPPLY_PROP_CHARGE_TYPE,
+ POWER_SUPPLY_PROP_CHARGE_FULL,
+ POWER_SUPPLY_PROP_CHARGE_FULL_DESIGN,
+ POWER_SUPPLY_PROP_CHARGE_EMPTY_DESIGN,
+ POWER_SUPPLY_PROP_CHARGE_NOW,
+ POWER_SUPPLY_PROP_CONSTANT_CHARGE_VOLTAGE_MAX,
+ POWER_SUPPLY_PROP_VOLTAGE_AVG,
+ POWER_SUPPLY_PROP_CONSTANT_CHARGE_CURRENT_MAX,
+ POWER_SUPPLY_PROP_CURRENT_AVG,
+ POWER_SUPPLY_PROP_VOLTAGE_MIN_DESIGN,
+ POWER_SUPPLY_PROP_CAPACITY,
+ POWER_SUPPLY_PROP_VOLTAGE_MAX_DESIGN,
+};
+
+static enum power_supply_property rk817_chg_props[] = {
+ POWER_SUPPLY_PROP_ONLINE,
+ POWER_SUPPLY_PROP_USB_TYPE,
+ POWER_SUPPLY_PROP_VOLTAGE_MAX_DESIGN,
+ POWER_SUPPLY_PROP_VOLTAGE_MIN_DESIGN,
+ POWER_SUPPLY_PROP_VOLTAGE_AVG,
+};
+
+static enum power_supply_usb_type rk817_usb_type[] = {
+ POWER_SUPPLY_USB_TYPE_DCP,
+ POWER_SUPPLY_USB_TYPE_UNKNOWN,
+};
+
+static const struct power_supply_desc rk817_bat_desc = {
+ .name = "rk817-battery",
+ .type = POWER_SUPPLY_TYPE_BATTERY,
+ .properties = rk817_bat_props,
+ .num_properties = ARRAY_SIZE(rk817_bat_props),
+ .get_property = rk817_bat_get_prop,
+};
+
+static const struct power_supply_desc rk817_chg_desc = {
+ .name = "rk817-charger",
+ .type = POWER_SUPPLY_TYPE_USB,
+ .usb_types = rk817_usb_type,
+ .num_usb_types = ARRAY_SIZE(rk817_usb_type),
+ .properties = rk817_chg_props,
+ .num_properties = ARRAY_SIZE(rk817_chg_props),
+ .get_property = rk817_chg_get_prop,
+};
+
+static int rk817_read_battery_nvram_values(struct rk817_charger *charger)
+{
+ u8 bulk_reg[3];
+ int ret;
+
+ /* Read the nvram data for full charge capacity. */
+ ret = regmap_bulk_read(charger->rk808->regmap,
+ RK817_GAS_GAUGE_DATA3, bulk_reg, 3);
+ if (ret < 0)
+ return ret;
+ charger->fcc_mah = get_unaligned_le24(bulk_reg);
+
+ /*
+ * Sanity checking for values equal to zero or less than would be
+ * practical for this device (BSP Kernel assumes 500mAH or less) for
+ * practicality purposes. Also check if the value is too large and
+ * correct it.
+ */
+ if ((charger->fcc_mah < 500) ||
+ ((charger->fcc_mah * 1000) > charger->bat_charge_full_design_uah)) {
+ dev_info(charger->dev,
+ "Invalid NVRAM max charge, setting to %u uAH\n",
+ charger->bat_charge_full_design_uah);
+ charger->fcc_mah = charger->bat_charge_full_design_uah / 1000;
+ }
+
+ /*
+ * Read the nvram for state of charge. Sanity check for values greater
+ * than 100 (10000). If the value is off it should get corrected
+ * automatically when the voltage drops to the min (soc is 0) or when
+ * the battery is full (soc is 100).
+ */
+ ret = regmap_bulk_read(charger->rk808->regmap,
+ RK817_GAS_GAUGE_BAT_R1, bulk_reg, 3);
+ if (ret < 0)
+ return ret;
+ charger->soc = get_unaligned_le24(bulk_reg);
+ if (charger->soc > 10000)
+ charger->soc = 10000;
+
+ return 0;
+}
+
+static int
+rk817_read_or_set_full_charge_on_boot(struct rk817_charger *charger,
+ struct power_supply_battery_info *bat_info)
+{
+ struct rk808 *rk808 = charger->rk808;
+ u8 bulk_reg[4];
+ u32 boot_voltage, boot_charge_mah, tmp;
+ int ret, reg, off_time;
+ bool first_boot;
+
+ /*
+ * Check if the battery is uninitalized. If it is, the columb counter
+ * needs to be set up.
+ */
+ ret = regmap_read(rk808->regmap, RK817_GAS_GAUGE_GG_STS, ®);
+ if (ret < 0)
+ return ret;
+ first_boot = reg & RK817_BAT_CON;
+ /*
+ * If the battery is uninitialized, use the poweron voltage and an ocv
+ * lookup to guess our charge. The number won't be very accurate until
+ * we hit either our minimum voltage (0%) or full charge (100%).
+ */
+ if (first_boot) {
+ regmap_bulk_read(rk808->regmap, RK817_GAS_GAUGE_PWRON_VOL_H,
+ bulk_reg, 2);
+ tmp = get_unaligned_be16(bulk_reg);
+ boot_voltage = (charger->voltage_k * tmp) +
+ 1000 * charger->voltage_b;
+ /*
+ * Since only implementation has no working thermistor, assume
+ * 20C for OCV lookup. If lookup fails, report error with OCV
+ * table.
+ */
+ charger->soc = power_supply_batinfo_ocv2cap(bat_info,
+ boot_voltage,
+ 20) * 1000;
+ if (charger->soc < 0)
+ charger->soc = 0;
+
+ /* Guess that full charge capacity is the design capacity */
+ charger->fcc_mah = charger->bat_charge_full_design_uah / 1000;
+ /*
+ * Set battery as "set up". BSP driver uses this value even
+ * though datasheet claims it's a read-only value.
+ */
+ regmap_write_bits(rk808->regmap, RK817_GAS_GAUGE_GG_STS,
+ RK817_BAT_CON, 0);
+ /* Save nvram values */
+ ret = rk817_record_battery_nvram_values(charger);
+ if (ret < 0)
+ return ret;
+ } else {
+ ret = rk817_read_battery_nvram_values(charger);
+ if (ret < 0)
+ return ret;
+
+ regmap_bulk_read(rk808->regmap, RK817_GAS_GAUGE_Q_PRES_H3,
+ bulk_reg, 4);
+ tmp = get_unaligned_be32(bulk_reg);
+ if (tmp < 0)
+ tmp = 0;
+ boot_charge_mah = ADC_TO_CHARGE_UAH(tmp,
+ charger->res_div) / 1000;
+ /*
+ * Check if the columb counter has been off for more than 300
+ * minutes as it tends to drift downward. If so, re-init soc
+ * with the boot voltage instead. Note the unit values for the
+ * OFF_CNT register appear to be in decaminutes and stops
+ * counting at 2550 (0xFF) minutes. BSP kernel used OCV, but
+ * for me occasionally that would show invalid values. Boot
+ * voltage is only accurate for me on first poweron (not
+ * reboots), but we shouldn't ever encounter an OFF_CNT more
+ * than 0 on a reboot anyway.
+ */
+ regmap_read(rk808->regmap, RK817_GAS_GAUGE_OFF_CNT, &off_time);
+ if (off_time >= 30) {
+ regmap_bulk_read(rk808->regmap,
+ RK817_GAS_GAUGE_PWRON_VOL_H,
+ bulk_reg, 2);
+ tmp = get_unaligned_be16(bulk_reg);
+ boot_voltage = (charger->voltage_k * tmp) +
+ 1000 * charger->voltage_b;
+ charger->soc =
+ power_supply_batinfo_ocv2cap(bat_info,
+ boot_voltage,
+ 20) * 1000;
+ } else {
+ charger->soc = (boot_charge_mah * 1000 * 100 /
+ charger->fcc_mah);
+ }
+ }
+
+ regmap_bulk_read(rk808->regmap, RK817_GAS_GAUGE_PWRON_VOL_H,
+ bulk_reg, 2);
+ tmp = get_unaligned_be16(bulk_reg);
+ boot_voltage = (charger->voltage_k * tmp) + 1000 * charger->voltage_b;
+ regmap_bulk_read(rk808->regmap, RK817_GAS_GAUGE_Q_PRES_H3,
+ bulk_reg, 4);
+ tmp = get_unaligned_be32(bulk_reg);
+ if (tmp < 0)
+ tmp = 0;
+ boot_charge_mah = ADC_TO_CHARGE_UAH(tmp, charger->res_div) / 1000;
+ regmap_bulk_read(rk808->regmap, RK817_GAS_GAUGE_OCV_VOL_H,
+ bulk_reg, 2);
+ tmp = get_unaligned_be16(bulk_reg);
+ boot_voltage = (charger->voltage_k * tmp) + 1000 * charger->voltage_b;
+
+ /*
+ * Now we have our full charge capacity and soc, init the columb
+ * counter.
+ */
+ boot_charge_mah = charger->soc * charger->fcc_mah / 100 / 1000;
+ if (boot_charge_mah > charger->fcc_mah)
+ boot_charge_mah = charger->fcc_mah;
+ tmp = CHARGE_TO_ADC(boot_charge_mah, charger->res_div);
+ put_unaligned_be32(tmp, bulk_reg);
+ ret = regmap_bulk_write(rk808->regmap, RK817_GAS_GAUGE_Q_INIT_H3,
+ bulk_reg, 4);
+ if (ret < 0)
+ return ret;
+
+ /* Set QMAX value to max design capacity. */
+ tmp = CHARGE_TO_ADC((charger->bat_charge_full_design_uah / 1000),
+ charger->res_div);
+ put_unaligned_be32(tmp, bulk_reg);
+ ret = regmap_bulk_write(rk808->regmap, RK817_GAS_GAUGE_Q_MAX_H3,
+ bulk_reg, 4);
+ if (ret < 0)
+ return ret;
+
+ return 0;
+}
+
+static int rk817_battery_init(struct rk817_charger *charger,
+ struct power_supply_battery_info *bat_info)
+{
+ struct rk808 *rk808 = charger->rk808;
+ u32 tmp, max_chg_vol_mv, max_chg_cur_ma;
+ u8 max_chg_vol_reg, chg_term_i_reg, max_chg_cur_reg;
+ int ret, chg_term_ma;
+ u8 bulk_reg[2];
+
+ /* Get initial plug state */
+ regmap_read(rk808->regmap, RK817_SYS_STS, &tmp);
+ charger->plugged_in = (tmp & RK817_PLUG_IN_STS);
+
+ /*
+ * Turn on all ADC functions to measure battery, USB, and sys voltage,
+ * as well as batt temp. Note only tested implementation so far does
+ * not use a battery with a thermistor.
+ */
+ regmap_write(rk808->regmap, RK817_GAS_GAUGE_ADC_CONFIG0, 0xfc);
+
+ /*
+ * Set relax mode voltage sampling interval and ADC offset calibration
+ * interval to 8 minutes to mirror BSP kernel. Set voltage and current
+ * modes to average to mirror BSP kernel.
+ */
+ regmap_write(rk808->regmap, RK817_GAS_GAUGE_GG_CON, 0x04);
+
+ /* Calibrate voltage like the BSP does here. */
+ rk817_bat_calib_vol(charger);
+
+ /* Write relax threshold, derived from sleep enter current. */
+ tmp = CURRENT_TO_ADC(charger->sleep_enter_current_ua,
+ charger->res_div);
+ put_unaligned_be16(tmp, bulk_reg);
+ regmap_bulk_write(rk808->regmap, RK817_GAS_GAUGE_RELAX_THRE_H,
+ bulk_reg, 2);
+
+ /* Write sleep sample current, derived from sleep filter current. */
+ tmp = CURRENT_TO_ADC(charger->sleep_filter_current_ua,
+ charger->res_div);
+ put_unaligned_be16(tmp, bulk_reg);
+ regmap_bulk_write(rk808->regmap, RK817_GAS_GAUGE_SLEEP_CON_SAMP_CUR_H,
+ bulk_reg, 2);
+
+ /* Restart battery relax voltage */
+ regmap_write_bits(rk808->regmap, RK817_GAS_GAUGE_GG_STS,
+ RK817_RELAX_VOL_UPD, (0x0 << 2));
+
+ /*
+ * Set OCV Threshold Voltage to 127.5mV. This was hard coded like this
+ * in the BSP.
+ */
+ regmap_write(rk808->regmap, RK817_GAS_GAUGE_OCV_THRE_VOL, 0xff);
+
+ /*
+ * Set maximum charging voltage to battery max voltage. Trying to be
+ * incredibly safe with these value, as setting them wrong could
+ * overcharge the battery, which would be very bad.
+ */
+ max_chg_vol_mv = bat_info->constant_charge_voltage_max_uv / 1000;
+ max_chg_cur_ma = bat_info->constant_charge_current_max_ua / 1000;
+
+ if (max_chg_vol_mv < 4100) {
+ return dev_err_probe(charger->dev, -EINVAL,
+ "invalid max charger voltage, value %u unsupported\n",
+ max_chg_vol_mv * 1000);
+ }
+ if (max_chg_vol_mv > 4450) {
+ dev_info(charger->dev,
+ "Setting max charge voltage to 4450000uv\n");
+ max_chg_vol_mv = 4450;
+ }
+
+ if (max_chg_cur_ma < 500) {
+ return dev_err_probe(charger->dev, -EINVAL,
+ "invalid max charger current, value %u unsupported\n",
+ max_chg_cur_ma * 1000);
+ }
+ if (max_chg_cur_ma > 3500)
+ dev_info(charger->dev,
+ "Setting max charge current to 3500000ua\n");
+
+ /*
+ * Now that the values are sanity checked, if we subtract 4100 from the
+ * max voltage and divide by 50, we conviently get the exact value for
+ * the registers, which are 4.1v, 4.15v, 4.2v, 4.25v, 4.3v, 4.35v,
+ * 4.4v, and 4.45v; these correspond to values 0x00 through 0x07.
+ */
+ max_chg_vol_reg = (max_chg_vol_mv - 4100) / 50;
+
+ max_chg_cur_reg = rk817_chg_cur_to_reg(max_chg_cur_ma);
+
+ if (max_chg_vol_reg < 0 || max_chg_vol_reg > 7) {
+ return dev_err_probe(charger->dev, -EINVAL,
+ "invalid max charger voltage, value %u unsupported\n",
+ max_chg_vol_mv * 1000);
+ }
+ if (max_chg_cur_reg < 0 || max_chg_cur_reg > 7) {
+ return dev_err_probe(charger->dev, -EINVAL,
+ "invalid max charger current, value %u unsupported\n",
+ max_chg_cur_ma * 1000);
+ }
+
+ /*
+ * Write the values to the registers, and deliver an emergency warning
+ * in the event they are not written correctly.
+ */
+ ret = regmap_write_bits(rk808->regmap, RK817_PMIC_CHRG_OUT,
+ RK817_CHRG_VOL_SEL, (max_chg_vol_reg << 4));
+ if (ret) {
+ dev_emerg(charger->dev,
+ "Danger, unable to set max charger voltage: %u\n",
+ ret);
+ }
+
+ ret = regmap_write_bits(rk808->regmap, RK817_PMIC_CHRG_OUT,
+ RK817_CHRG_CUR_SEL, max_chg_cur_reg);
+ if (ret) {
+ dev_emerg(charger->dev,
+ "Danger, unable to set max charger current: %u\n",
+ ret);
+ }
+
+ /* Set charge finishing mode to analog */
+ regmap_write_bits(rk808->regmap, RK817_PMIC_CHRG_TERM,
+ RK817_CHRG_TERM_ANA_DIG, (0x0 << 2));
+
+ /*
+ * Set charge finish current, warn if value not in range and keep
+ * default.
+ */
+ chg_term_ma = bat_info->charge_term_current_ua / 1000;
+ if (chg_term_ma < 150 || chg_term_ma > 400) {
+ dev_warn(charger->dev,
+ "Invalid charge termination %u, keeping default\n",
+ chg_term_ma * 1000);
+ chg_term_ma = 200;
+ }
+
+ /*
+ * Values of 150ma, 200ma, 300ma, and 400ma correspond to 00, 01, 10,
+ * and 11.
+ */
+ chg_term_i_reg = (chg_term_ma - 100) / 100;
+ regmap_write_bits(rk808->regmap, RK817_PMIC_CHRG_TERM,
+ RK817_CHRG_TERM_ANA_SEL, chg_term_i_reg);
+
+ ret = rk817_read_or_set_full_charge_on_boot(charger, bat_info);
+ if (ret < 0)
+ return ret;
+
+ /*
+ * Set minimum USB input voltage to 4.5v and enable USB voltage input
+ * limit.
+ */
+ regmap_write_bits(rk808->regmap, RK817_PMIC_CHRG_IN,
+ RK817_USB_VLIM_SEL, (0x05 << 4));
+ regmap_write_bits(rk808->regmap, RK817_PMIC_CHRG_IN, RK817_USB_VLIM_EN,
+ (0x01 << 7));
+
+ /*
+ * Set average USB input current limit to 1.5A and enable USB current
+ * input limit.
+ */
+ regmap_write_bits(rk808->regmap, RK817_PMIC_CHRG_IN,
+ RK817_USB_ILIM_SEL, 0x03);
+ regmap_write_bits(rk808->regmap, RK817_PMIC_CHRG_IN, RK817_USB_ILIM_EN,
+ (0x01 << 3));
+
+ return 0;
+}
+
+static void rk817_charging_monitor(struct work_struct *work)
+{
+ struct rk817_charger *charger;
+
+ charger = container_of(work, struct rk817_charger, work.work);
+
+ rk817_read_props(charger);
+
+ /* Run every 8 seconds like the BSP driver did. */
+ queue_delayed_work(system_wq, &charger->work, msecs_to_jiffies(8000));
+}
+
+static int rk817_charger_probe(struct platform_device *pdev)
+{
+ struct rk808 *rk808 = dev_get_drvdata(pdev->dev.parent);
+ struct rk817_charger *charger;
+ struct device_node *node;
+ struct power_supply_battery_info *bat_info;
+ struct device *dev = &pdev->dev;
+ struct power_supply_config pscfg = {};
+ int plugin_irq, plugout_irq;
+ int of_value;
+ int ret;
+
+ node = of_get_child_by_name(dev->parent->of_node, "charger");
+ if (!node)
+ return -ENODEV;
+
+ charger = devm_kzalloc(&pdev->dev, sizeof(*charger), GFP_KERNEL);
+ if (!charger)
+ return -ENOMEM;
+
+ charger->rk808 = rk808;
+
+ charger->dev = &pdev->dev;
+ platform_set_drvdata(pdev, charger);
+
+ rk817_bat_calib_vol(charger);
+
+ pscfg.drv_data = charger;
+ pscfg.of_node = node;
+
+ /*
+ * Get sample resistor value. Note only values of 10000 or 20000
+ * microohms are allowed. Schematic for my test implementation (an
+ * Odroid Go Advance) shows a 10 milliohm resistor for reference.
+ */
+ ret = of_property_read_u32(node, "rockchip,resistor-sense-micro-ohms",
+ &of_value);
+ if (ret < 0) {
+ return dev_err_probe(dev, ret,
+ "Error reading sample resistor value\n");
+ }
+ /*
+ * Store as a 1 or a 2, since all we really use the value for is as a
+ * divisor in some calculations.
+ */
+ charger->res_div = (of_value == 20000) ? 2 : 1;
+
+ /*
+ * Get sleep enter current value. Not sure what this value is for
+ * other than to help calibrate the relax threshold.
+ */
+ ret = of_property_read_u32(node,
+ "rockchip,sleep-enter-current-microamp",
+ &of_value);
+ if (ret < 0) {
+ return dev_err_probe(dev, ret,
+ "Error reading sleep enter cur value\n");
+ }
+ charger->sleep_enter_current_ua = of_value;
+
+ /* Get sleep filter current value */
+ ret = of_property_read_u32(node,
+ "rockchip,sleep-filter-current-microamp",
+ &of_value);
+ if (ret < 0) {
+ return dev_err_probe(dev, ret,
+ "Error reading sleep filter cur value\n");
+ }
+
+ charger->sleep_filter_current_ua = of_value;
+
+ charger->bat_ps = devm_power_supply_register(&pdev->dev,
+ &rk817_bat_desc, &pscfg);
+
+ charger->chg_ps = devm_power_supply_register(&pdev->dev,
+ &rk817_chg_desc, &pscfg);
+
+ if (IS_ERR(charger->chg_ps))
+ return dev_err_probe(dev, -EINVAL,
+ "Battery failed to probe\n");
+
+ if (IS_ERR(charger->chg_ps))
+ return dev_err_probe(dev, -EINVAL,
+ "Charger failed to probe\n");
+
+ ret = power_supply_get_battery_info(charger->bat_ps,
+ &bat_info);
+ if (ret) {
+ return dev_err_probe(dev, ret,
+ "Unable to get battery info: %d\n", ret);
+ }
+
+ if ((bat_info->charge_full_design_uah <= 0) ||
+ (bat_info->voltage_min_design_uv <= 0) ||
+ (bat_info->voltage_max_design_uv <= 0) ||
+ (bat_info->constant_charge_voltage_max_uv <= 0) ||
+ (bat_info->constant_charge_current_max_ua <= 0) ||
+ (bat_info->charge_term_current_ua <= 0)) {
+ return dev_err_probe(dev, -EINVAL,
+ "Required bat info missing or invalid\n");
+ }
+
+ charger->bat_charge_full_design_uah = bat_info->charge_full_design_uah;
+ charger->bat_voltage_min_design_uv = bat_info->voltage_min_design_uv;
+ charger->bat_voltage_max_design_uv = bat_info->voltage_max_design_uv;
+
+ /*
+ * Has to run after power_supply_get_battery_info as it depends on some
+ * values discovered from that routine.
+ */
+ ret = rk817_battery_init(charger, bat_info);
+ if (ret)
+ return ret;
+
+ power_supply_put_battery_info(charger->bat_ps, bat_info);
+
+ plugin_irq = platform_get_irq(pdev, 0);
+ if (plugin_irq < 0)
+ return plugin_irq;
+
+ plugout_irq = platform_get_irq(pdev, 1);
+ if (plugout_irq < 0)
+ return plugout_irq;
+
+ ret = devm_request_threaded_irq(charger->dev, plugin_irq, NULL,
+ rk817_plug_in_isr,
+ IRQF_TRIGGER_RISING | IRQF_ONESHOT,
+ "rk817_plug_in", charger);
+ if (ret) {
+ return dev_err_probe(&pdev->dev, ret,
+ "plug_in_irq request failed!\n");
+ }
+
+ ret = devm_request_threaded_irq(charger->dev, plugout_irq, NULL,
+ rk817_plug_out_isr,
+ IRQF_TRIGGER_RISING | IRQF_ONESHOT,
+ "rk817_plug_out", charger);
+ if (ret) {
+ return dev_err_probe(&pdev->dev, ret,
+ "plug_out_irq request failed!\n");
+ }
+
+ ret = devm_delayed_work_autocancel(&pdev->dev, &charger->work,
+ rk817_charging_monitor);
+ if (ret)
+ return ret;
+
+ /* Force the first update immediately. */
+ mod_delayed_work(system_wq, &charger->work, 0);
+
+ return 0;
+}
+
+
+static struct platform_driver rk817_charger_driver = {
+ .probe = rk817_charger_probe,
+ .driver = {
+ .name = "rk817-charger",
+ },
+};
+module_platform_driver(rk817_charger_driver);
+
+MODULE_DESCRIPTION("Battery power supply driver for RK817 PMIC");
+MODULE_AUTHOR("Maya Matuszczyk <maccraft123mc@gmail.com>");
+MODULE_AUTHOR("Chris Morgan <macromorgan@hotmail.com>");
+MODULE_LICENSE("GPL");
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