diff mbox series

[V9,3/4] power: supply: Add charger driver for Rockchip RK817

Message ID 20220823193015.10229-4-macroalpha82@gmail.com
State New
Headers show
Series power: supply: Add Support for RK817 Charger | expand

Commit Message

Chris Morgan Aug. 23, 2022, 7:30 p.m. UTC
From: Chris Morgan <macromorgan@hotmail.com>

Add support for the Rockchip rk817 battery charger integrated into the
rk817 PMIC.

Signed-off-by: Chris Morgan <macromorgan@hotmail.com>
Signed-off-by: Maya Matuszczyk <maccraft123mc@gmail.com>
---
 drivers/power/supply/Kconfig         |    6 +
 drivers/power/supply/Makefile        |    1 +
 drivers/power/supply/rk817_charger.c | 1157 ++++++++++++++++++++++++++
 3 files changed, 1164 insertions(+)
 create mode 100644 drivers/power/supply/rk817_charger.c
diff mbox series

Patch

diff --git a/drivers/power/supply/Kconfig b/drivers/power/supply/Kconfig
index 1aa8323ad9f6..56e70a68679a 100644
--- a/drivers/power/supply/Kconfig
+++ b/drivers/power/supply/Kconfig
@@ -708,6 +708,12 @@  config CHARGER_BQ256XX
 	  charge management and system power path management devices for single
 	  cell Li-ion and Li-polymer batteries.
 
+config CHARGER_RK817
+	tristate "Rockchip RK817 PMIC Battery Charger"
+	depends on MFD_RK808
+	help
+	  Say Y to include support for Rockchip RK817 Battery Charger.
+
 config CHARGER_SMB347
 	tristate "Summit Microelectronics SMB3XX Battery Charger"
 	depends on I2C
diff --git a/drivers/power/supply/Makefile b/drivers/power/supply/Makefile
index 7f02f36aea55..3040a1de81b8 100644
--- a/drivers/power/supply/Makefile
+++ b/drivers/power/supply/Makefile
@@ -91,6 +91,7 @@  obj-$(CONFIG_CHARGER_BQ2515X)	+= bq2515x_charger.o
 obj-$(CONFIG_CHARGER_BQ25890)	+= bq25890_charger.o
 obj-$(CONFIG_CHARGER_BQ25980)	+= bq25980_charger.o
 obj-$(CONFIG_CHARGER_BQ256XX)	+= bq256xx_charger.o
+obj-$(CONFIG_CHARGER_RK817)	+= rk817_charger.o
 obj-$(CONFIG_CHARGER_SMB347)	+= smb347-charger.o
 obj-$(CONFIG_CHARGER_TPS65090)	+= tps65090-charger.o
 obj-$(CONFIG_CHARGER_TPS65217)	+= tps65217_charger.o
diff --git a/drivers/power/supply/rk817_charger.c b/drivers/power/supply/rk817_charger.c
new file mode 100644
index 000000000000..3197447af564
--- /dev/null
+++ b/drivers/power/supply/rk817_charger.c
@@ -0,0 +1,1157 @@ 
+// 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;
+
+	/* 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 same value to the nvram location used by the BSP kernel
+	 * for the rsoc value.
+	 */
+	put_unaligned_le24(charger->soc, 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, &reg);
+	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, &reg);
+	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, &reg);
+	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, &reg);
+	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, &reg);
+	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.
+	 */
+	if (charger->fcc_mah < 500) {
+		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. */
+	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);
+
+	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, &reg);
+	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) ||
+	    (!bat_info->voltage_min_design_uv) ||
+	    (!bat_info->voltage_max_design_uv) ||
+	    (!bat_info->constant_charge_voltage_max_uv) ||
+	    (!bat_info->constant_charge_current_max_ua) ||
+	    (!bat_info->charge_term_current_ua)) {
+		return dev_err_probe(dev, -EINVAL,
+				     "Required battery info missing.\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");