From: Amit Sunil Dhamne <amitsd@google.com>
Add support for MAX77759 battery charger driver. This is a 4A 1-Cell
Li+/LiPoly dual input switch mode charger. While the device can support
USB & wireless charger inputs, this implementation only supports USB
input. This implementation supports both buck and boost modes.
Signed-off-by: Amit Sunil Dhamne <amitsd@google.com>
---
MAINTAINERS | 6 +
drivers/power/supply/Kconfig | 11 +
drivers/power/supply/Makefile | 1 +
drivers/power/supply/max77759_charger.c | 768 ++++++++++++++++++++++++++++++++
4 files changed, 786 insertions(+)
diff --git a/MAINTAINERS b/MAINTAINERS
index 67db88b04537..7f6d1c5c2569 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -15553,6 +15553,12 @@ F: drivers/mfd/max77759.c
F: drivers/nvmem/max77759-nvmem.c
F: include/linux/mfd/max77759.h
+MAXIM MAX77759 BATTERY CHARGER DRIVER
+M: Amit Sunil Dhamne <amitsd@google.com>
+L: linux-kernel@vger.kernel.org
+S: Maintained
+F: drivers/power/supply/max77759_charger.c
+
MAXIM MAX77802 PMIC REGULATOR DEVICE DRIVER
M: Javier Martinez Canillas <javier@dowhile0.org>
L: linux-kernel@vger.kernel.org
diff --git a/drivers/power/supply/Kconfig b/drivers/power/supply/Kconfig
index 92f9f7aae92f..3a2cdb95c98e 100644
--- a/drivers/power/supply/Kconfig
+++ b/drivers/power/supply/Kconfig
@@ -631,6 +631,17 @@ config CHARGER_MAX77705
help
Say Y to enable support for the Maxim MAX77705 battery charger.
+config CHARGER_MAX77759
+ tristate "Maxim MAX77759 battery charger driver"
+ depends on MFD_MAX77759 && REGULATOR
+ default MFD_MAX77759
+ help
+ Say M or Y here to enable the MAX77759 battery charger. MAX77759
+ charger is a function of the MAX77759 PMIC. This is a dual input
+ switch-mode charger. This driver supports buck and OTG boost modes.
+
+ If built as a module, it will be called max77759_charger.
+
config CHARGER_MAX77976
tristate "Maxim MAX77976 battery charger driver"
depends on I2C
diff --git a/drivers/power/supply/Makefile b/drivers/power/supply/Makefile
index 4b79d5abc49a..6af905875ad5 100644
--- a/drivers/power/supply/Makefile
+++ b/drivers/power/supply/Makefile
@@ -128,3 +128,4 @@ obj-$(CONFIG_CHARGER_SURFACE) += surface_charger.o
obj-$(CONFIG_BATTERY_UG3105) += ug3105_battery.o
obj-$(CONFIG_CHARGER_QCOM_SMB2) += qcom_smbx.o
obj-$(CONFIG_FUEL_GAUGE_MM8013) += mm8013.o
+obj-$(CONFIG_CHARGER_MAX77759) += max77759_charger.o
diff --git a/drivers/power/supply/max77759_charger.c b/drivers/power/supply/max77759_charger.c
new file mode 100644
index 000000000000..d4e02764ba04
--- /dev/null
+++ b/drivers/power/supply/max77759_charger.c
@@ -0,0 +1,768 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * max77759_charger.c - Battery charger driver for MAX77759 charger device.
+ *
+ * Copyright 2025 Google LLC.
+ */
+
+#include <linux/bitfield.h>
+#include <linux/cleanup.h>
+#include <linux/device.h>
+#include <linux/devm-helpers.h>
+#include <linux/interrupt.h>
+#include <linux/irq.h>
+#include <linux/linear_range.h>
+#include <linux/mfd/max77759.h>
+#include <linux/module.h>
+#include <linux/mod_devicetable.h>
+#include <linux/mutex.h>
+#include <linux/of.h>
+#include <linux/platform_device.h>
+#include <linux/power_supply.h>
+#include <linux/regmap.h>
+#include <linux/regulator/driver.h>
+#include <linux/string_choices.h>
+#include <linux/workqueue.h>
+
+/* Default values for Fast Charge Current & Float Voltage */
+#define CHG_CC_DEFAULT_UA 2266770
+#define CHG_FV_DEFAULT_MV 4300
+
+#define MAX_NUM_RETRIES 3
+#define PSY_WORK_RETRY_DELAY_MS 10
+
+#define FOREACH_IRQ(S) \
+ S(AICL), \
+ S(CHGIN), \
+ S(CHG), \
+ S(INLIM), \
+ S(BAT_OILO), \
+ S(CHG_STA_CC), \
+ S(CHG_STA_CV), \
+ S(CHG_STA_TO), \
+ S(CHG_STA_DONE)
+
+#define GENERATE_ENUM(e) e
+#define GENERATE_STRING(s) #s
+
+enum {
+ FOREACH_IRQ(GENERATE_ENUM)
+};
+
+static const char *const chgr_irqs_str[] = {
+ FOREACH_IRQ(GENERATE_STRING)
+};
+
+#define NUM_IRQS ARRAY_SIZE(chgr_irqs_str)
+
+/* Fast charge current limits (in uA) */
+static const struct linear_range chgcc_limit_ranges[] = {
+ LINEAR_RANGE(133330, 0x0, 0x2, 0),
+ LINEAR_RANGE(200000, 0x3, 0x3C, 66670),
+};
+
+/* Charge Termination Voltage Limits (in mV) */
+static const struct linear_range chg_cv_prm_ranges[] = {
+ LINEAR_RANGE(3800, 0x38, 0x39, 100),
+ LINEAR_RANGE(4000, 0x0, 0x32, 10),
+};
+
+/* USB input current limits (in uA) */
+static const struct linear_range chgin_ilim_ranges[] = {
+ LINEAR_RANGE(100000, 0x3, 0x7F, 25000),
+};
+
+struct max77759_charger {
+ struct device *dev;
+ struct regmap *regmap;
+ struct power_supply *psy;
+ struct regulator_dev *chgin_otg_rdev;
+ struct notifier_block nb;
+ struct power_supply *tcpm_psy;
+ struct delayed_work psy_work;
+ struct mutex retry_lock; /* Protects psy_work_retry_cnt */
+ u32 psy_work_retry_cnt;
+ int irqs[NUM_IRQS];
+ struct mutex lock; /* protects the state below */
+ enum max77759_chgr_mode mode;
+};
+
+static inline int unlock_prot_regs(struct max77759_charger *chg, bool unlock)
+{
+ return regmap_update_bits(chg->regmap, MAX77759_CHGR_REG_CHG_CNFG_06,
+ MAX77759_CHGR_REG_CHG_CNFG_06_CHGPROT, unlock
+ ? MAX77759_CHGR_REG_CHG_CNFG_06_CHGPROT : 0);
+}
+
+static int charger_input_valid(struct max77759_charger *chg)
+{
+ u32 val;
+ int ret;
+
+ ret = regmap_read(chg->regmap, MAX77759_CHGR_REG_CHG_INT_OK, &val);
+ if (ret)
+ return ret;
+
+ return (val & MAX77759_CHGR_REG_CHG_INT_CHG) &&
+ (val & MAX77759_CHGR_REG_CHG_INT_CHGIN);
+}
+
+static int get_online(struct max77759_charger *chg)
+{
+ u32 val;
+ int ret;
+
+ ret = charger_input_valid(chg);
+ if (ret <= 0)
+ return ret;
+
+ ret = regmap_read(chg->regmap, MAX77759_CHGR_REG_CHG_DETAILS_02, &val);
+ if (ret)
+ return ret;
+
+ guard(mutex)(&chg->lock);
+
+ return (val & MAX77759_CHGR_REG_CHG_DETAILS_02_CHGIN_STS) &&
+ (chg->mode == MAX77759_CHGR_MODE_CHG_BUCK_ON);
+}
+
+static int get_status(struct max77759_charger *chg)
+{
+ u32 val;
+ int ret;
+
+ ret = regmap_read(chg->regmap, MAX77759_CHGR_REG_CHG_DETAILS_01, &val);
+ if (ret)
+ return ret;
+
+ switch (FIELD_GET(MAX77759_CHGR_REG_CHG_DETAILS_01_CHG_DTLS, val)) {
+ case MAX77759_CHGR_CHG_DTLS_PREQUAL:
+ case MAX77759_CHGR_CHG_DTLS_CC:
+ case MAX77759_CHGR_CHG_DTLS_CV:
+ case MAX77759_CHGR_CHG_DTLS_TO:
+ return POWER_SUPPLY_STATUS_CHARGING;
+ case MAX77759_CHGR_CHG_DTLS_DONE:
+ return POWER_SUPPLY_STATUS_FULL;
+ case MAX77759_CHGR_CHG_DTLS_TIMER_FAULT:
+ case MAX77759_CHGR_CHG_DTLS_SUSP_BATT_THM:
+ case MAX77759_CHGR_CHG_DTLS_OFF_WDOG_TIMER:
+ case MAX77759_CHGR_CHG_DTLS_SUSP_JEITA:
+ return POWER_SUPPLY_STATUS_NOT_CHARGING;
+ case MAX77759_CHGR_CHG_DTLS_OFF:
+ return POWER_SUPPLY_STATUS_DISCHARGING;
+ default:
+ break;
+ }
+
+ return POWER_SUPPLY_STATUS_UNKNOWN;
+}
+
+static int get_charge_type(struct max77759_charger *chg)
+{
+ u32 val;
+ int ret;
+
+ ret = regmap_read(chg->regmap, MAX77759_CHGR_REG_CHG_DETAILS_01, &val);
+ if (ret)
+ return ret;
+
+ switch (FIELD_GET(MAX77759_CHGR_REG_CHG_DETAILS_01_CHG_DTLS, val)) {
+ case MAX77759_CHGR_CHG_DTLS_PREQUAL:
+ return POWER_SUPPLY_CHARGE_TYPE_TRICKLE;
+ case MAX77759_CHGR_CHG_DTLS_CC:
+ case MAX77759_CHGR_CHG_DTLS_CV:
+ return POWER_SUPPLY_CHARGE_TYPE_FAST;
+ case MAX77759_CHGR_CHG_DTLS_TO:
+ return POWER_SUPPLY_CHARGE_TYPE_STANDARD;
+ case MAX77759_CHGR_CHG_DTLS_DONE:
+ case MAX77759_CHGR_CHG_DTLS_TIMER_FAULT:
+ case MAX77759_CHGR_CHG_DTLS_SUSP_BATT_THM:
+ case MAX77759_CHGR_CHG_DTLS_OFF_WDOG_TIMER:
+ case MAX77759_CHGR_CHG_DTLS_SUSP_JEITA:
+ case MAX77759_CHGR_CHG_DTLS_OFF:
+ return POWER_SUPPLY_CHARGE_TYPE_NONE;
+ default:
+ break;
+ }
+
+ return POWER_SUPPLY_CHARGE_TYPE_UNKNOWN;
+}
+
+static int get_chg_health(struct max77759_charger *chg)
+{
+ u32 val;
+ int ret;
+
+ ret = regmap_read(chg->regmap, MAX77759_CHGR_REG_CHG_DETAILS_00, &val);
+ if (ret)
+ return ret;
+
+ switch (FIELD_GET(MAX77759_CHGR_REG_CHG_DETAILS_00_CHGIN_DTLS, val)) {
+ case MAX77759_CHGR_CHGIN_DTLS_VBUS_UNDERVOLTAGE:
+ case MAX77759_CHGR_CHGIN_DTLS_VBUS_MARGINAL_VOLTAGE:
+ return POWER_SUPPLY_HEALTH_UNDERVOLTAGE;
+ case MAX77759_CHGR_CHGIN_DTLS_VBUS_OVERVOLTAGE:
+ return POWER_SUPPLY_HEALTH_OVERVOLTAGE;
+ case MAX77759_CHGR_CHGIN_DTLS_VBUS_VALID:
+ return POWER_SUPPLY_HEALTH_GOOD;
+ default:
+ break;
+ }
+
+ return POWER_SUPPLY_HEALTH_UNKNOWN;
+}
+
+static int get_batt_health(struct max77759_charger *chg)
+{
+ u32 val;
+ int ret;
+
+ ret = regmap_read(chg->regmap, MAX77759_CHGR_REG_CHG_DETAILS_01, &val);
+ if (ret)
+ return ret;
+
+ switch (FIELD_GET(MAX77759_CHGR_REG_CHG_DETAILS_01_BAT_DTLS, val)) {
+ case MAX77759_CHGR_BAT_DTLS_NO_BATT_CHG_SUSP:
+ return POWER_SUPPLY_HEALTH_NO_BATTERY;
+ case MAX77759_CHGR_BAT_DTLS_DEAD_BATTERY:
+ return POWER_SUPPLY_HEALTH_DEAD;
+ case MAX77759_CHGR_BAT_DTLS_BAT_CHG_TIMER_FAULT:
+ return POWER_SUPPLY_HEALTH_SAFETY_TIMER_EXPIRE;
+ case MAX77759_CHGR_BAT_DTLS_BAT_OKAY:
+ case MAX77759_CHGR_BAT_DTLS_BAT_ONLY_MODE:
+ return POWER_SUPPLY_HEALTH_GOOD;
+ case MAX77759_CHGR_BAT_DTLS_BAT_UNDERVOLTAGE:
+ return POWER_SUPPLY_HEALTH_UNDERVOLTAGE;
+ case MAX77759_CHGR_BAT_DTLS_BAT_OVERVOLTAGE:
+ return POWER_SUPPLY_HEALTH_OVERVOLTAGE;
+ case MAX77759_CHGR_BAT_DTLS_BAT_OVERCURRENT:
+ return POWER_SUPPLY_HEALTH_OVERCURRENT;
+ default:
+ break;
+ }
+
+ return POWER_SUPPLY_HEALTH_UNKNOWN;
+}
+
+static int get_health(struct max77759_charger *chg)
+{
+ int ret;
+
+ ret = get_online(chg);
+ if (ret < 0)
+ return ret;
+
+ if (ret) {
+ ret = get_chg_health(chg);
+ if (ret < 0 || ret != POWER_SUPPLY_HEALTH_GOOD)
+ return ret;
+ }
+
+ return get_batt_health(chg);
+}
+
+static int get_fast_charge_current(struct max77759_charger *chg)
+{
+ u32 regval, val;
+ int ret;
+
+ ret = regmap_read(chg->regmap, MAX77759_CHGR_REG_CHG_CNFG_02, ®val);
+ if (ret)
+ return ret;
+
+ regval = FIELD_GET(MAX77759_CHGR_REG_CHG_CNFG_02_CHGCC, regval);
+ ret = linear_range_get_value_array(chgcc_limit_ranges,
+ ARRAY_SIZE(chgcc_limit_ranges),
+ regval, &val);
+ return ret ? ret : val;
+}
+
+static int set_fast_charge_current_limit(struct max77759_charger *chg,
+ u32 cc_max_ua)
+{
+ bool found;
+ u32 regval;
+
+ linear_range_get_selector_high_array(chgcc_limit_ranges,
+ ARRAY_SIZE(chgcc_limit_ranges),
+ cc_max_ua, ®val, &found);
+ if (!found)
+ return -EINVAL;
+
+ return regmap_update_bits(chg->regmap, MAX77759_CHGR_REG_CHG_CNFG_02,
+ MAX77759_CHGR_REG_CHG_CNFG_02_CHGCC, regval);
+}
+
+static int get_float_voltage(struct max77759_charger *chg)
+{
+ u32 regval, val;
+ int ret;
+
+ ret = regmap_read(chg->regmap, MAX77759_CHGR_REG_CHG_CNFG_04, ®val);
+ if (ret)
+ return ret;
+
+ regval = FIELD_GET(MAX77759_CHGR_REG_CHG_CNFG_04_CHG_CV_PRM, regval);
+ ret = linear_range_get_value_array(chg_cv_prm_ranges,
+ ARRAY_SIZE(chg_cv_prm_ranges),
+ regval, &val);
+
+ return ret ? ret : val;
+}
+
+static int set_float_voltage_limit(struct max77759_charger *chg, u32 fv_mv)
+{
+ u32 regval;
+ bool found;
+
+ linear_range_get_selector_high_array(chg_cv_prm_ranges,
+ ARRAY_SIZE(chg_cv_prm_ranges),
+ fv_mv, ®val, &found);
+ if (!found)
+ return -EINVAL;
+
+ return regmap_update_bits(chg->regmap, MAX77759_CHGR_REG_CHG_CNFG_04,
+ MAX77759_CHGR_REG_CHG_CNFG_04_CHG_CV_PRM,
+ regval);
+}
+
+static int get_input_current_limit(struct max77759_charger *chg)
+{
+ u32 regval, val;
+ int ret;
+
+ ret = regmap_read(chg->regmap, MAX77759_CHGR_REG_CHG_CNFG_09, ®val);
+ if (ret)
+ return ret;
+
+ regval = FIELD_GET(MAX77759_CHGR_REG_CHG_CNFG_09_CHGIN_ILIM, regval);
+ regval = umax(regval, chgin_ilim_ranges[0].min_sel);
+
+ ret = linear_range_get_value_array(chgin_ilim_ranges,
+ ARRAY_SIZE(chgin_ilim_ranges),
+ regval, &val);
+
+ return ret ? ret : val;
+}
+
+static int set_input_current_limit(struct max77759_charger *chg, int ilim_ua)
+{
+ u32 regval;
+
+ if (ilim_ua < 0)
+ return -EINVAL;
+
+ linear_range_get_selector_within(chgin_ilim_ranges, ilim_ua, ®val);
+
+ return regmap_update_bits(chg->regmap, MAX77759_CHGR_REG_CHG_CNFG_09,
+ MAX77759_CHGR_REG_CHG_CNFG_09_CHGIN_ILIM,
+ regval);
+}
+
+static const enum power_supply_property max77759_charger_props[] = {
+ POWER_SUPPLY_PROP_ONLINE,
+ POWER_SUPPLY_PROP_PRESENT,
+ POWER_SUPPLY_PROP_STATUS,
+ POWER_SUPPLY_PROP_CHARGE_TYPE,
+ POWER_SUPPLY_PROP_HEALTH,
+ POWER_SUPPLY_PROP_CONSTANT_CHARGE_CURRENT_MAX,
+ POWER_SUPPLY_PROP_CONSTANT_CHARGE_VOLTAGE_MAX,
+ POWER_SUPPLY_PROP_INPUT_CURRENT_LIMIT,
+};
+
+static int max77759_charger_get_property(struct power_supply *psy,
+ enum power_supply_property psp,
+ union power_supply_propval *pval)
+{
+ struct max77759_charger *chg = power_supply_get_drvdata(psy);
+ int ret;
+
+ switch (psp) {
+ case POWER_SUPPLY_PROP_ONLINE:
+ ret = get_online(chg);
+ break;
+ case POWER_SUPPLY_PROP_PRESENT:
+ ret = charger_input_valid(chg);
+ break;
+ case POWER_SUPPLY_PROP_STATUS:
+ ret = get_status(chg);
+ break;
+ case POWER_SUPPLY_PROP_CHARGE_TYPE:
+ ret = get_charge_type(chg);
+ break;
+ case POWER_SUPPLY_PROP_HEALTH:
+ ret = get_health(chg);
+ break;
+ case POWER_SUPPLY_PROP_CONSTANT_CHARGE_CURRENT_MAX:
+ ret = get_fast_charge_current(chg);
+ break;
+ case POWER_SUPPLY_PROP_CONSTANT_CHARGE_VOLTAGE_MAX:
+ ret = get_float_voltage(chg);
+ break;
+ case POWER_SUPPLY_PROP_INPUT_CURRENT_LIMIT:
+ ret = get_input_current_limit(chg);
+ break;
+ default:
+ ret = -EINVAL;
+ }
+
+ pval->intval = ret;
+ return ret < 0 ? ret : 0;
+}
+
+static const struct power_supply_desc max77759_charger_desc = {
+ .name = "max77759-charger",
+ .type = POWER_SUPPLY_TYPE_USB,
+ .properties = max77759_charger_props,
+ .num_properties = ARRAY_SIZE(max77759_charger_props),
+ .get_property = max77759_charger_get_property,
+};
+
+static int charger_set_mode(struct max77759_charger *chg,
+ enum max77759_chgr_mode mode)
+{
+ int ret;
+
+ guard(mutex)(&chg->lock);
+
+ if (chg->mode == mode)
+ return 0;
+
+ if ((mode == MAX77759_CHGR_MODE_CHG_BUCK_ON ||
+ mode == MAX77759_CHGR_MODE_OTG_BOOST_ON) &&
+ chg->mode != MAX77759_CHGR_MODE_OFF) {
+ dev_err(chg->dev, "Invalid mode transition from %d to %d",
+ chg->mode, mode);
+ return -EINVAL;
+ }
+
+ ret = regmap_update_bits(chg->regmap, MAX77759_CHGR_REG_CHG_CNFG_00,
+ MAX77759_CHGR_REG_CHG_CNFG_00_MODE, mode);
+ if (ret)
+ return ret;
+
+ chg->mode = mode;
+ return 0;
+}
+
+static int enable_chgin_otg(struct regulator_dev *rdev)
+{
+ struct max77759_charger *chg = rdev_get_drvdata(rdev);
+
+ return charger_set_mode(chg, MAX77759_CHGR_MODE_OTG_BOOST_ON);
+}
+
+static int disable_chgin_otg(struct regulator_dev *rdev)
+{
+ struct max77759_charger *chg = rdev_get_drvdata(rdev);
+
+ return charger_set_mode(chg, MAX77759_CHGR_MODE_OFF);
+}
+
+static int chgin_otg_status(struct regulator_dev *rdev)
+{
+ struct max77759_charger *chg = rdev_get_drvdata(rdev);
+
+ guard(mutex)(&chg->lock);
+
+ return chg->mode == MAX77759_CHGR_MODE_OTG_BOOST_ON;
+}
+
+static const struct regulator_ops chgin_otg_reg_ops = {
+ .enable = enable_chgin_otg,
+ .disable = disable_chgin_otg,
+ .is_enabled = chgin_otg_status,
+};
+
+static const struct regulator_desc chgin_otg_reg_desc = {
+ .name = "chgin-otg",
+ .of_match = of_match_ptr("chgin-otg-regulator"),
+ .owner = THIS_MODULE,
+ .ops = &chgin_otg_reg_ops,
+ .fixed_uV = 5000000,
+ .n_voltages = 1,
+};
+
+static irqreturn_t irq_handler(int irq, void *data)
+{
+ struct max77759_charger *chg = data;
+
+ power_supply_changed(chg->psy);
+
+ return IRQ_HANDLED;
+}
+
+static irqreturn_t bat_oilo_irq_handler(int irq, void *data)
+{
+ struct max77759_charger *chg = data;
+
+ dev_warn_ratelimited(chg->dev, "Battery over-current threshold crossed");
+
+ return irq_handler(irq, data);
+}
+
+static int max77759_init_irqhandler(struct max77759_charger *chg)
+{
+ struct device *dev = chg->dev;
+ irq_handler_t thread_fn;
+ char *name;
+ int i, ret;
+
+ for (i = 0; i < ARRAY_SIZE(chgr_irqs_str); i++) {
+ ret = platform_get_irq_byname(to_platform_device(dev),
+ chgr_irqs_str[i]);
+ if (ret < 0)
+ return dev_err_probe(dev, ret,
+ "Failed to get irq resource for %s",
+ chgr_irqs_str[i]);
+
+ chg->irqs[i] = ret;
+ name = devm_kasprintf(dev, GFP_KERNEL, "%s:%s", dev_name(dev),
+ chgr_irqs_str[i]);
+ if (!name)
+ return dev_err_probe(dev, -ENOMEM,
+ "Failed to allocate space for irqname: %s",
+ chgr_irqs_str[i]);
+
+ if (i == BAT_OILO)
+ thread_fn = bat_oilo_irq_handler;
+ else
+ thread_fn = irq_handler;
+
+ ret = devm_request_threaded_irq(dev, chg->irqs[i], NULL,
+ thread_fn, 0, name, chg);
+ if (ret)
+ return dev_err_probe(dev, ret,
+ "Unable to register irq handler for %s",
+ chgr_irqs_str[i]);
+ }
+
+ return 0;
+}
+
+static int max77759_charger_init(struct max77759_charger *chg)
+{
+ struct power_supply_battery_info *info;
+ u32 regval, fast_chg_curr, fv;
+ int ret;
+
+ ret = regmap_read(chg->regmap, MAX77759_CHGR_REG_CHG_CNFG_00, ®val);
+ if (ret)
+ return ret;
+
+ chg->mode = FIELD_GET(MAX77759_CHGR_REG_CHG_CNFG_00_MODE, regval);
+ ret = charger_set_mode(chg, MAX77759_CHGR_MODE_OFF);
+ if (ret)
+ return ret;
+
+ if (power_supply_get_battery_info(chg->psy, &info)) {
+ fv = CHG_FV_DEFAULT_MV;
+ fast_chg_curr = CHG_CC_DEFAULT_UA;
+ } else {
+ fv = info->constant_charge_voltage_max_uv / 1000;
+ fast_chg_curr = info->constant_charge_current_max_ua;
+ }
+
+ ret = set_fast_charge_current_limit(chg, fast_chg_curr);
+ if (ret)
+ return ret;
+
+ ret = set_float_voltage_limit(chg, fv);
+ if (ret)
+ return ret;
+
+ ret = unlock_prot_regs(chg, true);
+ if (ret)
+ return ret;
+
+ /* Disable wireless charging input */
+ ret = regmap_update_bits(chg->regmap, MAX77759_CHGR_REG_CHG_CNFG_12,
+ MAX77759_CHGR_REG_CHG_CNFG_12_WCINSEL, 0);
+ if (ret)
+ return ret;
+
+ ret = regmap_update_bits(chg->regmap, MAX77759_CHGR_REG_CHG_CNFG_18,
+ MAX77759_CHGR_REG_CHG_CNFG_18_WDTEN, 0);
+ if (ret)
+ return ret;
+
+ return unlock_prot_regs(chg, false);
+}
+
+static void psy_work_item(struct work_struct *work)
+{
+ struct max77759_charger *chg =
+ container_of(work, struct max77759_charger, psy_work.work);
+ union power_supply_propval current_limit, online;
+ int ret;
+
+ ret = power_supply_get_property(chg->tcpm_psy,
+ POWER_SUPPLY_PROP_CURRENT_MAX,
+ ¤t_limit);
+ if (ret) {
+ dev_err(chg->dev,
+ "Failed to get CURRENT_MAX psy property, ret=%d",
+ ret);
+ goto err;
+ }
+
+ ret = power_supply_get_property(chg->tcpm_psy, POWER_SUPPLY_PROP_ONLINE,
+ &online);
+ if (ret) {
+ dev_err(chg->dev,
+ "Failed to get ONLINE psy property, ret=%d",
+ ret);
+ goto err;
+ }
+
+ if (online.intval && current_limit.intval) {
+ ret = set_input_current_limit(chg, current_limit.intval);
+ if (ret) {
+ dev_err(chg->dev,
+ "Unable to set current limit, ret=%d", ret);
+ goto err;
+ }
+
+ charger_set_mode(chg, MAX77759_CHGR_MODE_CHG_BUCK_ON);
+ } else {
+ charger_set_mode(chg, MAX77759_CHGR_MODE_OFF);
+ }
+
+ guard(mutex)(&chg->retry_lock);
+
+ if (chg->psy_work_retry_cnt)
+ dev_dbg(chg->dev, "chg psy_work succeeded after %u tries",
+ chg->psy_work_retry_cnt);
+ chg->psy_work_retry_cnt = 0;
+ return;
+
+err:
+ charger_set_mode(chg, MAX77759_CHGR_MODE_OFF);
+ guard(mutex)(&chg->retry_lock);
+
+ if (chg->psy_work_retry_cnt >= MAX_NUM_RETRIES) {
+ dev_err(chg->dev, "chg psy work failed, giving up");
+ return;
+ }
+
+ ++chg->psy_work_retry_cnt;
+ dev_dbg(chg->dev, "Retrying %u/%u chg psy_work",
+ chg->psy_work_retry_cnt, MAX_NUM_RETRIES);
+ schedule_delayed_work(&chg->psy_work,
+ msecs_to_jiffies(PSY_WORK_RETRY_DELAY_MS));
+}
+
+static int psy_changed(struct notifier_block *nb, unsigned long evt, void *data)
+{
+ struct max77759_charger *chg = container_of(nb, struct max77759_charger,
+ nb);
+ static const char *psy_name = "tcpm-source";
+ struct power_supply *psy = data;
+
+ if (!strnstr(psy->desc->name, psy_name, strlen(psy_name)) ||
+ evt != PSY_EVENT_PROP_CHANGED)
+ return NOTIFY_OK;
+
+ chg->tcpm_psy = psy;
+ scoped_guard(mutex, &chg->retry_lock)
+ chg->psy_work_retry_cnt = 0;
+
+ schedule_delayed_work(&chg->psy_work, 0);
+
+ return NOTIFY_OK;
+}
+
+static void max_tcpci_unregister_psy_notifier(void *nb)
+{
+ power_supply_unreg_notifier(nb);
+}
+
+static int max77759_charger_probe(struct platform_device *pdev)
+{
+ struct regulator_config chgin_otg_reg_cfg;
+ struct power_supply_config psy_cfg;
+ struct device *dev = &pdev->dev;
+ struct max77759_charger *chg;
+ int ret;
+
+ device_set_of_node_from_dev(dev, dev->parent);
+ chg = devm_kzalloc(dev, sizeof(*chg), GFP_KERNEL);
+ if (!chg)
+ return -ENOMEM;
+
+ platform_set_drvdata(pdev, chg);
+ chg->dev = dev;
+ chg->regmap = dev_get_regmap(dev->parent, "charger");
+ if (!chg->regmap)
+ return dev_err_probe(dev, -ENODEV, "Missing regmap");
+
+ ret = devm_mutex_init(dev, &chg->lock);
+ if (ret)
+ return dev_err_probe(dev, ret, "Failed to initialize lock");
+
+ ret = devm_mutex_init(dev, &chg->retry_lock);
+ if (ret)
+ return dev_err_probe(dev, ret,
+ "Failed to initialize retry_lock");
+
+ psy_cfg.fwnode = dev_fwnode(dev);
+ psy_cfg.drv_data = chg;
+ chg->psy = devm_power_supply_register(dev, &max77759_charger_desc,
+ &psy_cfg);
+ if (IS_ERR(chg->psy))
+ return dev_err_probe(dev, -EPROBE_DEFER,
+ "Failed to register psy, ret=%ld",
+ PTR_ERR(chg->psy));
+
+ ret = max77759_charger_init(chg);
+ if (ret)
+ return dev_err_probe(dev, ret,
+ "Failed to initialize max77759 charger");
+
+ chgin_otg_reg_cfg.dev = dev;
+ chgin_otg_reg_cfg.driver_data = chg;
+ chgin_otg_reg_cfg.of_node = dev_of_node(dev);
+ chg->chgin_otg_rdev = devm_regulator_register(dev, &chgin_otg_reg_desc,
+ &chgin_otg_reg_cfg);
+ if (IS_ERR(chg->chgin_otg_rdev))
+ return dev_err_probe(dev, PTR_ERR(chg->chgin_otg_rdev),
+ "Failed to register chgin otg regulator");
+
+ ret = devm_delayed_work_autocancel(dev, &chg->psy_work, psy_work_item);
+ if (ret)
+ return dev_err_probe(dev, ret, "Failed to initialize psy work");
+
+ chg->nb.notifier_call = psy_changed;
+ ret = power_supply_reg_notifier(&chg->nb);
+ if (ret)
+ return dev_err_probe(dev, ret,
+ "Unable to register psy notifier");
+
+ ret = devm_add_action_or_reset(dev, max_tcpci_unregister_psy_notifier,
+ &chg->nb);
+ if (ret)
+ return dev_err_probe(dev, ret,
+ "Failed to add devm action to unregister psy notifier");
+
+ return max77759_init_irqhandler(chg);
+}
+
+static const struct platform_device_id max77759_charger_id[] = {
+ { .name = "max77759-charger", },
+ { }
+};
+MODULE_DEVICE_TABLE(platform, max77759_charger_id);
+
+static struct platform_driver max77759_charger_driver = {
+ .driver = {
+ .name = "max77759-charger",
+ .probe_type = PROBE_PREFER_ASYNCHRONOUS,
+ },
+ .probe = max77759_charger_probe,
+ .id_table = max77759_charger_id,
+};
+module_platform_driver(max77759_charger_driver);
+
+MODULE_AUTHOR("Amit Sunil Dhamne <amitsd@google.com>");
+MODULE_DESCRIPTION("Maxim MAX77759 charger driver");
+MODULE_LICENSE("GPL");
--
2.53.0.273.g2a3d683680-googHi Amit,
All below comments are only minor, feel free to ignore them.
On Sat, 2026-02-14 at 03:12 +0000, Amit Sunil Dhamne via B4 Relay wrote:
> From: Amit Sunil Dhamne <amitsd@google.com>
>
> Add support for MAX77759 battery charger driver. This is a 4A 1-Cell
> Li+/LiPoly dual input switch mode charger. While the device can support
> USB & wireless charger inputs, this implementation only supports USB
> input. This implementation supports both buck and boost modes.
>
> Signed-off-by: Amit Sunil Dhamne <amitsd@google.com>
> ---
> MAINTAINERS | 6 +
> drivers/power/supply/Kconfig | 11 +
> drivers/power/supply/Makefile | 1 +
> drivers/power/supply/max77759_charger.c | 768 ++++++++++++++++++++++++++++++++
> 4 files changed, 786 insertions(+)
[...]
> diff --git a/drivers/power/supply/max77759_charger.c b/drivers/power/supply/max77759_charger.c
> new file mode 100644
> index 000000000000..d4e02764ba04
> --- /dev/null
> +++ b/drivers/power/supply/max77759_charger.c
> @@ -0,0 +1,768 @@
[...]
> +
> +/* USB input current limits (in uA) */
> +static const struct linear_range chgin_ilim_ranges[] = {
> + LINEAR_RANGE(100000, 0x3, 0x7F, 25000),
> +};
Shouldn't this one also have a entry for 0x00...0x02:
LINEAR_RANGE(100000, 0x0, 0x2, 0),
Then you can also drop the umax() call in get_input_current_limit().
Ah, I see now there is no linear_range_get_selector_within_array(),
meaning the code is fine as-is, unless you want to add that as
well :-)
[...]
> +static int max77759_charger_init(struct max77759_charger *chg)
> +{
> + struct power_supply_battery_info *info;
> + u32 regval, fast_chg_curr, fv;
> + int ret;
> +
> + ret = regmap_read(chg->regmap, MAX77759_CHGR_REG_CHG_CNFG_00, ®val);
> + if (ret)
> + return ret;
> +
> + chg->mode = FIELD_GET(MAX77759_CHGR_REG_CHG_CNFG_00_MODE, regval);
> + ret = charger_set_mode(chg, MAX77759_CHGR_MODE_OFF);
> + if (ret)
> + return ret;
> +
> + if (power_supply_get_battery_info(chg->psy, &info)) {
> + fv = CHG_FV_DEFAULT_MV;
> + fast_chg_curr = CHG_CC_DEFAULT_UA;
> + } else {
> + fv = info->constant_charge_voltage_max_uv / 1000;
> + fast_chg_curr = info->constant_charge_current_max_ua;
> + }
> +
> + ret = set_fast_charge_current_limit(chg, fast_chg_curr);
> + if (ret)
> + return ret;
> +
> + ret = set_float_voltage_limit(chg, fv);
> + if (ret)
> + return ret;
> +
> + ret = unlock_prot_regs(chg, true);
> + if (ret)
> + return ret;
> +
> + /* Disable wireless charging input */
> + ret = regmap_update_bits(chg->regmap, MAX77759_CHGR_REG_CHG_CNFG_12,
> + MAX77759_CHGR_REG_CHG_CNFG_12_WCINSEL, 0);
> + if (ret)
> + return ret;
> +
> + ret = regmap_update_bits(chg->regmap, MAX77759_CHGR_REG_CHG_CNFG_18,
> + MAX77759_CHGR_REG_CHG_CNFG_18_WDTEN, 0);
> + if (ret)
> + return ret;
> +
> + return unlock_prot_regs(chg, false);
Should early error returns here try to lock the protection again? Something
like:
+ ret = unlock_prot_regs(chg, true);
+ if (ret)
+ return ret;
+
+ /* Disable wireless charging input */
+ ret = regmap_update_bits(chg->regmap, MAX77759_CHGR_REG_CHG_CNFG_12,
+ MAX77759_CHGR_REG_CHG_CNFG_12_WCINSEL, 0);
+ if (ret)
+ goto relock;
+
+ ret = regmap_update_bits(chg->regmap, MAX77759_CHGR_REG_CHG_CNFG_18,
+ MAX77759_CHGR_REG_CHG_CNFG_18_WDTEN, 0);
+ if (ret)
+ goto relock;
+
+ return unlock_prot_regs(chg, false);
+
+relock:
+ (void) unlock_prot_regs(chg, false);
+ return ret;
I guess if one of the regmap_update_bits() failed, then locking the
registers might not work either, so I have no strong opinion on
adding that.
With or without updates:
Reviewed-by: André Draszik <andre.draszik@linaro.org>
Cheers,
Andre'
Hi André,
On 2/17/26 5:14 AM, André Draszik wrote:
> Hi Amit,
>
> All below comments are only minor, feel free to ignore them.
>
> On Sat, 2026-02-14 at 03:12 +0000, Amit Sunil Dhamne via B4 Relay wrote:
>> From: Amit Sunil Dhamne <amitsd@google.com>
>>
>> Add support for MAX77759 battery charger driver. This is a 4A 1-Cell
>> Li+/LiPoly dual input switch mode charger. While the device can support
>> USB & wireless charger inputs, this implementation only supports USB
>> input. This implementation supports both buck and boost modes.
>>
>> Signed-off-by: Amit Sunil Dhamne <amitsd@google.com>
>> ---
>> MAINTAINERS | 6 +
>> drivers/power/supply/Kconfig | 11 +
>> drivers/power/supply/Makefile | 1 +
>> drivers/power/supply/max77759_charger.c | 768 ++++++++++++++++++++++++++++++++
>> 4 files changed, 786 insertions(+)
> [...]
>
>> diff --git a/drivers/power/supply/max77759_charger.c b/drivers/power/supply/max77759_charger.c
>> new file mode 100644
>> index 000000000000..d4e02764ba04
>> --- /dev/null
>> +++ b/drivers/power/supply/max77759_charger.c
>> @@ -0,0 +1,768 @@
> [...]
>
>> +
>> +/* USB input current limits (in uA) */
>> +static const struct linear_range chgin_ilim_ranges[] = {
>> + LINEAR_RANGE(100000, 0x3, 0x7F, 25000),
>> +};
> Shouldn't this one also have a entry for 0x00...0x02:
> LINEAR_RANGE(100000, 0x0, 0x2, 0),
>
> Then you can also drop the umax() call in get_input_current_limit().
>
> Ah, I see now there is no linear_range_get_selector_within_array(),
> meaning the code is fine as-is, unless you want to add that as
> well :-)
>
>
> [...]
I would go with the code being as is for now. :-)
>
>> +static int max77759_charger_init(struct max77759_charger *chg)
>> +{
>> + struct power_supply_battery_info *info;
>> + u32 regval, fast_chg_curr, fv;
>> + int ret;
>> +
>> + ret = regmap_read(chg->regmap, MAX77759_CHGR_REG_CHG_CNFG_00, ®val);
>> + if (ret)
>> + return ret;
>> +
>> + chg->mode = FIELD_GET(MAX77759_CHGR_REG_CHG_CNFG_00_MODE, regval);
>> + ret = charger_set_mode(chg, MAX77759_CHGR_MODE_OFF);
>> + if (ret)
>> + return ret;
>> +
>> + if (power_supply_get_battery_info(chg->psy, &info)) {
>> + fv = CHG_FV_DEFAULT_MV;
>> + fast_chg_curr = CHG_CC_DEFAULT_UA;
>> + } else {
>> + fv = info->constant_charge_voltage_max_uv / 1000;
>> + fast_chg_curr = info->constant_charge_current_max_ua;
>> + }
>> +
>> + ret = set_fast_charge_current_limit(chg, fast_chg_curr);
>> + if (ret)
>> + return ret;
>> +
>> + ret = set_float_voltage_limit(chg, fv);
>> + if (ret)
>> + return ret;
>> +
>> + ret = unlock_prot_regs(chg, true);
>> + if (ret)
>> + return ret;
>> +
>> + /* Disable wireless charging input */
>> + ret = regmap_update_bits(chg->regmap, MAX77759_CHGR_REG_CHG_CNFG_12,
>> + MAX77759_CHGR_REG_CHG_CNFG_12_WCINSEL, 0);
>> + if (ret)
>> + return ret;
>> +
>> + ret = regmap_update_bits(chg->regmap, MAX77759_CHGR_REG_CHG_CNFG_18,
>> + MAX77759_CHGR_REG_CHG_CNFG_18_WDTEN, 0);
>> + if (ret)
>> + return ret;
>> +
>> + return unlock_prot_regs(chg, false);
> Should early error returns here try to lock the protection again? Something
> like:
>
> + ret = unlock_prot_regs(chg, true);
> + if (ret)
> + return ret;
> +
> + /* Disable wireless charging input */
> + ret = regmap_update_bits(chg->regmap, MAX77759_CHGR_REG_CHG_CNFG_12,
> + MAX77759_CHGR_REG_CHG_CNFG_12_WCINSEL, 0);
> + if (ret)
> + goto relock;
> +
> + ret = regmap_update_bits(chg->regmap, MAX77759_CHGR_REG_CHG_CNFG_18,
> + MAX77759_CHGR_REG_CHG_CNFG_18_WDTEN, 0);
> + if (ret)
> + goto relock;
> +
> + return unlock_prot_regs(chg, false);
> +
> +relock:
> + (void) unlock_prot_regs(chg, false);
> + return ret;
>
> I guess if one of the regmap_update_bits() failed, then locking the
> registers might not work either, so I have no strong opinion on
> adding that.
Nice catch!
I need to send a next revision to keep the Linux Test Robot happy. I
will address this issue in that.
>
> With or without updates:
>
> Reviewed-by: André Draszik <andre.draszik@linaro.org>
>
LGTM! Thanks!
Regards,
Amit
> Cheers,
> Andre'
Hi Amit,
kernel test robot noticed the following build errors:
[auto build test ERROR on 8dfce8991b95d8625d0a1d2896e42f93b9d7f68d]
url: https://github.com/intel-lab-lkp/linux/commits/Amit-Sunil-Dhamne-via-B4-Relay/dt-bindings-mfd-maxim-max77759-reference-power-supply-schema-and-add-regulator-property/20260214-111637
base: 8dfce8991b95d8625d0a1d2896e42f93b9d7f68d
patch link: https://lore.kernel.org/r/20260214-max77759-charger-v6-5-28c09bda74b4%40google.com
patch subject: [PATCH v6 5/6] power: supply: max77759: add charger driver
config: powerpc64-randconfig-001-20260214 (https://download.01.org/0day-ci/archive/20260214/202602141606.igFDFWAJ-lkp@intel.com/config)
compiler: clang version 22.0.0git (https://github.com/llvm/llvm-project 9b8addffa70cee5b2acc5454712d9cf78ce45710)
reproduce (this is a W=1 build): (https://download.01.org/0day-ci/archive/20260214/202602141606.igFDFWAJ-lkp@intel.com/reproduce)
If you fix the issue in a separate patch/commit (i.e. not just a new version of
the same patch/commit), kindly add following tags
| Reported-by: kernel test robot <lkp@intel.com>
| Closes: https://lore.kernel.org/oe-kbuild-all/202602141606.igFDFWAJ-lkp@intel.com/
All errors (new ones prefixed by >>):
>> drivers/power/supply/max77759_charger.c:623:4: error: cannot jump from this goto statement to its label
623 | goto err;
| ^
drivers/power/supply/max77759_charger.c:631:2: note: jump bypasses initialization of variable with __attribute__((cleanup))
631 | guard(mutex)(&chg->retry_lock);
| ^
include/linux/cleanup.h:414:15: note: expanded from macro 'guard'
414 | CLASS(_name, __UNIQUE_ID(guard))
| ^
include/linux/compiler.h:168:2: note: expanded from macro '__UNIQUE_ID'
168 | __PASTE(__UNIQUE_ID_, \
| ^
include/linux/compiler_types.h:16:23: note: expanded from macro '__PASTE'
16 | #define __PASTE(a, b) ___PASTE(a, b)
| ^
include/linux/compiler_types.h:15:24: note: expanded from macro '___PASTE'
15 | #define ___PASTE(a, b) a##b
| ^
<scratch space>:18:1: note: expanded from here
18 | __UNIQUE_ID_guard_461
| ^
drivers/power/supply/max77759_charger.c:615:3: error: cannot jump from this goto statement to its label
615 | goto err;
| ^
drivers/power/supply/max77759_charger.c:631:2: note: jump bypasses initialization of variable with __attribute__((cleanup))
631 | guard(mutex)(&chg->retry_lock);
| ^
include/linux/cleanup.h:414:15: note: expanded from macro 'guard'
414 | CLASS(_name, __UNIQUE_ID(guard))
| ^
include/linux/compiler.h:168:2: note: expanded from macro '__UNIQUE_ID'
168 | __PASTE(__UNIQUE_ID_, \
| ^
include/linux/compiler_types.h:16:23: note: expanded from macro '__PASTE'
16 | #define __PASTE(a, b) ___PASTE(a, b)
| ^
include/linux/compiler_types.h:15:24: note: expanded from macro '___PASTE'
15 | #define ___PASTE(a, b) a##b
| ^
<scratch space>:18:1: note: expanded from here
18 | __UNIQUE_ID_guard_461
| ^
drivers/power/supply/max77759_charger.c:606:3: error: cannot jump from this goto statement to its label
606 | goto err;
| ^
drivers/power/supply/max77759_charger.c:631:2: note: jump bypasses initialization of variable with __attribute__((cleanup))
631 | guard(mutex)(&chg->retry_lock);
| ^
include/linux/cleanup.h:414:15: note: expanded from macro 'guard'
414 | CLASS(_name, __UNIQUE_ID(guard))
| ^
include/linux/compiler.h:168:2: note: expanded from macro '__UNIQUE_ID'
168 | __PASTE(__UNIQUE_ID_, \
| ^
include/linux/compiler_types.h:16:23: note: expanded from macro '__PASTE'
16 | #define __PASTE(a, b) ___PASTE(a, b)
| ^
include/linux/compiler_types.h:15:24: note: expanded from macro '___PASTE'
15 | #define ___PASTE(a, b) a##b
| ^
<scratch space>:18:1: note: expanded from here
18 | __UNIQUE_ID_guard_461
| ^
3 errors generated.
vim +623 drivers/power/supply/max77759_charger.c
591
592 static void psy_work_item(struct work_struct *work)
593 {
594 struct max77759_charger *chg =
595 container_of(work, struct max77759_charger, psy_work.work);
596 union power_supply_propval current_limit, online;
597 int ret;
598
599 ret = power_supply_get_property(chg->tcpm_psy,
600 POWER_SUPPLY_PROP_CURRENT_MAX,
601 ¤t_limit);
602 if (ret) {
603 dev_err(chg->dev,
604 "Failed to get CURRENT_MAX psy property, ret=%d",
605 ret);
606 goto err;
607 }
608
609 ret = power_supply_get_property(chg->tcpm_psy, POWER_SUPPLY_PROP_ONLINE,
610 &online);
611 if (ret) {
612 dev_err(chg->dev,
613 "Failed to get ONLINE psy property, ret=%d",
614 ret);
615 goto err;
616 }
617
618 if (online.intval && current_limit.intval) {
619 ret = set_input_current_limit(chg, current_limit.intval);
620 if (ret) {
621 dev_err(chg->dev,
622 "Unable to set current limit, ret=%d", ret);
> 623 goto err;
624 }
625
626 charger_set_mode(chg, MAX77759_CHGR_MODE_CHG_BUCK_ON);
627 } else {
628 charger_set_mode(chg, MAX77759_CHGR_MODE_OFF);
629 }
630
631 guard(mutex)(&chg->retry_lock);
632
633 if (chg->psy_work_retry_cnt)
634 dev_dbg(chg->dev, "chg psy_work succeeded after %u tries",
635 chg->psy_work_retry_cnt);
636 chg->psy_work_retry_cnt = 0;
637 return;
638
639 err:
640 charger_set_mode(chg, MAX77759_CHGR_MODE_OFF);
641 guard(mutex)(&chg->retry_lock);
642
643 if (chg->psy_work_retry_cnt >= MAX_NUM_RETRIES) {
644 dev_err(chg->dev, "chg psy work failed, giving up");
645 return;
646 }
647
648 ++chg->psy_work_retry_cnt;
649 dev_dbg(chg->dev, "Retrying %u/%u chg psy_work",
650 chg->psy_work_retry_cnt, MAX_NUM_RETRIES);
651 schedule_delayed_work(&chg->psy_work,
652 msecs_to_jiffies(PSY_WORK_RETRY_DELAY_MS));
653 }
654
--
0-DAY CI Kernel Test Service
https://github.com/intel/lkp-tests/wiki
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