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-rw-r--r--drivers/power/supply/max8903_charger.c423
1 files changed, 423 insertions, 0 deletions
diff --git a/drivers/power/supply/max8903_charger.c b/drivers/power/supply/max8903_charger.c
new file mode 100644
index 000000000..54d50b55f
--- /dev/null
+++ b/drivers/power/supply/max8903_charger.c
@@ -0,0 +1,423 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * max8903_charger.c - Maxim 8903 USB/Adapter Charger Driver
+ *
+ * Copyright (C) 2011 Samsung Electronics
+ * MyungJoo Ham <myungjoo.ham@samsung.com>
+ */
+
+#include <linux/gpio/consumer.h>
+#include <linux/interrupt.h>
+#include <linux/module.h>
+#include <linux/of.h>
+#include <linux/of_device.h>
+#include <linux/slab.h>
+#include <linux/power_supply.h>
+#include <linux/platform_device.h>
+
+struct max8903_data {
+ struct device *dev;
+ struct power_supply *psy;
+ struct power_supply_desc psy_desc;
+ /*
+ * GPIOs
+ * chg, flt, dcm and usus are optional.
+ * dok or uok must be present.
+ * If dok is present, cen must be present.
+ */
+ struct gpio_desc *cen; /* Charger Enable input */
+ struct gpio_desc *dok; /* DC (Adapter) Power OK output */
+ struct gpio_desc *uok; /* USB Power OK output */
+ struct gpio_desc *chg; /* Charger status output */
+ struct gpio_desc *flt; /* Fault output */
+ struct gpio_desc *dcm; /* Current-Limit Mode input (1: DC, 2: USB) */
+ struct gpio_desc *usus; /* USB Suspend Input (1: suspended) */
+ bool fault;
+ bool usb_in;
+ bool ta_in;
+};
+
+static enum power_supply_property max8903_charger_props[] = {
+ POWER_SUPPLY_PROP_STATUS, /* Charger status output */
+ POWER_SUPPLY_PROP_ONLINE, /* External power source */
+ POWER_SUPPLY_PROP_HEALTH, /* Fault or OK */
+};
+
+static int max8903_get_property(struct power_supply *psy,
+ enum power_supply_property psp,
+ union power_supply_propval *val)
+{
+ struct max8903_data *data = power_supply_get_drvdata(psy);
+
+ switch (psp) {
+ case POWER_SUPPLY_PROP_STATUS:
+ val->intval = POWER_SUPPLY_STATUS_UNKNOWN;
+ if (data->chg) {
+ if (gpiod_get_value(data->chg))
+ /* CHG asserted */
+ val->intval = POWER_SUPPLY_STATUS_CHARGING;
+ else if (data->usb_in || data->ta_in)
+ val->intval = POWER_SUPPLY_STATUS_NOT_CHARGING;
+ else
+ val->intval = POWER_SUPPLY_STATUS_DISCHARGING;
+ }
+ break;
+ case POWER_SUPPLY_PROP_ONLINE:
+ val->intval = 0;
+ if (data->usb_in || data->ta_in)
+ val->intval = 1;
+ break;
+ case POWER_SUPPLY_PROP_HEALTH:
+ val->intval = POWER_SUPPLY_HEALTH_GOOD;
+ if (data->fault)
+ val->intval = POWER_SUPPLY_HEALTH_UNSPEC_FAILURE;
+ break;
+ default:
+ return -EINVAL;
+ }
+
+ return 0;
+}
+
+static irqreturn_t max8903_dcin(int irq, void *_data)
+{
+ struct max8903_data *data = _data;
+ bool ta_in;
+ enum power_supply_type old_type;
+
+ /*
+ * This means the line is asserted.
+ *
+ * The signal is active low, but the inversion is handled in the GPIO
+ * library as the line should be flagged GPIO_ACTIVE_LOW in the device
+ * tree.
+ */
+ ta_in = gpiod_get_value(data->dok);
+
+ if (ta_in == data->ta_in)
+ return IRQ_HANDLED;
+
+ data->ta_in = ta_in;
+
+ /* Set Current-Limit-Mode 1:DC 0:USB */
+ if (data->dcm)
+ gpiod_set_value(data->dcm, ta_in);
+
+ /* Charger Enable / Disable */
+ if (data->cen) {
+ int val;
+
+ if (ta_in)
+ /* Certainly enable if DOK is asserted */
+ val = 1;
+ else if (data->usb_in)
+ /* Enable if the USB charger is enabled */
+ val = 1;
+ else
+ /* Else default-disable */
+ val = 0;
+
+ gpiod_set_value(data->cen, val);
+ }
+
+ dev_dbg(data->dev, "TA(DC-IN) Charger %s.\n", ta_in ?
+ "Connected" : "Disconnected");
+
+ old_type = data->psy_desc.type;
+
+ if (data->ta_in)
+ data->psy_desc.type = POWER_SUPPLY_TYPE_MAINS;
+ else if (data->usb_in)
+ data->psy_desc.type = POWER_SUPPLY_TYPE_USB;
+ else
+ data->psy_desc.type = POWER_SUPPLY_TYPE_BATTERY;
+
+ if (old_type != data->psy_desc.type)
+ power_supply_changed(data->psy);
+
+ return IRQ_HANDLED;
+}
+
+static irqreturn_t max8903_usbin(int irq, void *_data)
+{
+ struct max8903_data *data = _data;
+ bool usb_in;
+ enum power_supply_type old_type;
+
+ /*
+ * This means the line is asserted.
+ *
+ * The signal is active low, but the inversion is handled in the GPIO
+ * library as the line should be flagged GPIO_ACTIVE_LOW in the device
+ * tree.
+ */
+ usb_in = gpiod_get_value(data->uok);
+
+ if (usb_in == data->usb_in)
+ return IRQ_HANDLED;
+
+ data->usb_in = usb_in;
+
+ /* Do not touch Current-Limit-Mode */
+
+ /* Charger Enable / Disable */
+ if (data->cen) {
+ int val;
+
+ if (usb_in)
+ /* Certainly enable if UOK is asserted */
+ val = 1;
+ else if (data->ta_in)
+ /* Enable if the DC charger is enabled */
+ val = 1;
+ else
+ /* Else default-disable */
+ val = 0;
+
+ gpiod_set_value(data->cen, val);
+ }
+
+ dev_dbg(data->dev, "USB Charger %s.\n", usb_in ?
+ "Connected" : "Disconnected");
+
+ old_type = data->psy_desc.type;
+
+ if (data->ta_in)
+ data->psy_desc.type = POWER_SUPPLY_TYPE_MAINS;
+ else if (data->usb_in)
+ data->psy_desc.type = POWER_SUPPLY_TYPE_USB;
+ else
+ data->psy_desc.type = POWER_SUPPLY_TYPE_BATTERY;
+
+ if (old_type != data->psy_desc.type)
+ power_supply_changed(data->psy);
+
+ return IRQ_HANDLED;
+}
+
+static irqreturn_t max8903_fault(int irq, void *_data)
+{
+ struct max8903_data *data = _data;
+ bool fault;
+
+ /*
+ * This means the line is asserted.
+ *
+ * The signal is active low, but the inversion is handled in the GPIO
+ * library as the line should be flagged GPIO_ACTIVE_LOW in the device
+ * tree.
+ */
+ fault = gpiod_get_value(data->flt);
+
+ if (fault == data->fault)
+ return IRQ_HANDLED;
+
+ data->fault = fault;
+
+ if (fault)
+ dev_err(data->dev, "Charger suffers a fault and stops.\n");
+ else
+ dev_err(data->dev, "Charger recovered from a fault.\n");
+
+ return IRQ_HANDLED;
+}
+
+static int max8903_setup_gpios(struct platform_device *pdev)
+{
+ struct max8903_data *data = platform_get_drvdata(pdev);
+ struct device *dev = &pdev->dev;
+ bool ta_in = false;
+ bool usb_in = false;
+ enum gpiod_flags flags;
+
+ data->dok = devm_gpiod_get_optional(dev, "dok", GPIOD_IN);
+ if (IS_ERR(data->dok))
+ return dev_err_probe(dev, PTR_ERR(data->dok),
+ "failed to get DOK GPIO");
+ if (data->dok) {
+ gpiod_set_consumer_name(data->dok, data->psy_desc.name);
+ /*
+ * The DC OK is pulled up to 1 and goes low when a charger
+ * is plugged in (active low) but in the device tree the
+ * line is marked as GPIO_ACTIVE_LOW so we get a 1 (asserted)
+ * here if the DC charger is plugged in.
+ */
+ ta_in = gpiod_get_value(data->dok);
+ }
+
+ data->uok = devm_gpiod_get_optional(dev, "uok", GPIOD_IN);
+ if (IS_ERR(data->uok))
+ return dev_err_probe(dev, PTR_ERR(data->uok),
+ "failed to get UOK GPIO");
+ if (data->uok) {
+ gpiod_set_consumer_name(data->uok, data->psy_desc.name);
+ /*
+ * The USB OK is pulled up to 1 and goes low when a USB charger
+ * is plugged in (active low) but in the device tree the
+ * line is marked as GPIO_ACTIVE_LOW so we get a 1 (asserted)
+ * here if the USB charger is plugged in.
+ */
+ usb_in = gpiod_get_value(data->uok);
+ }
+
+ /* Either DC OK or USB OK must be provided */
+ if (!data->dok && !data->uok) {
+ dev_err(dev, "no valid power source\n");
+ return -EINVAL;
+ }
+
+ /*
+ * If either charger is already connected at this point,
+ * assert the CEN line and enable charging from the start.
+ *
+ * The line is active low but also marked with GPIO_ACTIVE_LOW
+ * in the device tree, so when we assert the line with
+ * GPIOD_OUT_HIGH the line will be driven low.
+ */
+ flags = (ta_in || usb_in) ? GPIOD_OUT_HIGH : GPIOD_OUT_LOW;
+ /*
+ * If DC OK is provided, Charger Enable CEN is compulsory
+ * so this is not optional here.
+ */
+ data->cen = devm_gpiod_get(dev, "cen", flags);
+ if (IS_ERR(data->cen))
+ return dev_err_probe(dev, PTR_ERR(data->cen),
+ "failed to get CEN GPIO");
+ gpiod_set_consumer_name(data->cen, data->psy_desc.name);
+
+ /*
+ * If the DC charger is connected, then select it.
+ *
+ * The DCM line should be marked GPIO_ACTIVE_HIGH in the
+ * device tree. Driving it high will enable the DC charger
+ * input over the USB charger input.
+ */
+ flags = ta_in ? GPIOD_OUT_HIGH : GPIOD_OUT_LOW;
+ data->dcm = devm_gpiod_get_optional(dev, "dcm", flags);
+ if (IS_ERR(data->dcm))
+ return dev_err_probe(dev, PTR_ERR(data->dcm),
+ "failed to get DCM GPIO");
+ gpiod_set_consumer_name(data->dcm, data->psy_desc.name);
+
+ data->chg = devm_gpiod_get_optional(dev, "chg", GPIOD_IN);
+ if (IS_ERR(data->chg))
+ return dev_err_probe(dev, PTR_ERR(data->chg),
+ "failed to get CHG GPIO");
+ gpiod_set_consumer_name(data->chg, data->psy_desc.name);
+
+ data->flt = devm_gpiod_get_optional(dev, "flt", GPIOD_IN);
+ if (IS_ERR(data->flt))
+ return dev_err_probe(dev, PTR_ERR(data->flt),
+ "failed to get FLT GPIO");
+ gpiod_set_consumer_name(data->flt, data->psy_desc.name);
+
+ data->usus = devm_gpiod_get_optional(dev, "usus", GPIOD_IN);
+ if (IS_ERR(data->usus))
+ return dev_err_probe(dev, PTR_ERR(data->usus),
+ "failed to get USUS GPIO");
+ gpiod_set_consumer_name(data->usus, data->psy_desc.name);
+
+ data->fault = false;
+ data->ta_in = ta_in;
+ data->usb_in = usb_in;
+
+ return 0;
+}
+
+static int max8903_probe(struct platform_device *pdev)
+{
+ struct max8903_data *data;
+ struct device *dev = &pdev->dev;
+ struct power_supply_config psy_cfg = {};
+ int ret = 0;
+
+ data = devm_kzalloc(dev, sizeof(struct max8903_data), GFP_KERNEL);
+ if (!data)
+ return -ENOMEM;
+
+ data->dev = dev;
+ platform_set_drvdata(pdev, data);
+
+ ret = max8903_setup_gpios(pdev);
+ if (ret)
+ return ret;
+
+ data->psy_desc.name = "max8903_charger";
+ data->psy_desc.type = (data->ta_in) ? POWER_SUPPLY_TYPE_MAINS :
+ ((data->usb_in) ? POWER_SUPPLY_TYPE_USB :
+ POWER_SUPPLY_TYPE_BATTERY);
+ data->psy_desc.get_property = max8903_get_property;
+ data->psy_desc.properties = max8903_charger_props;
+ data->psy_desc.num_properties = ARRAY_SIZE(max8903_charger_props);
+
+ psy_cfg.of_node = dev->of_node;
+ psy_cfg.drv_data = data;
+
+ data->psy = devm_power_supply_register(dev, &data->psy_desc, &psy_cfg);
+ if (IS_ERR(data->psy)) {
+ dev_err(dev, "failed: power supply register.\n");
+ return PTR_ERR(data->psy);
+ }
+
+ if (data->dok) {
+ ret = devm_request_threaded_irq(dev, gpiod_to_irq(data->dok),
+ NULL, max8903_dcin,
+ IRQF_TRIGGER_FALLING |
+ IRQF_TRIGGER_RISING | IRQF_ONESHOT,
+ "MAX8903 DC IN", data);
+ if (ret) {
+ dev_err(dev, "Cannot request irq %d for DC (%d)\n",
+ gpiod_to_irq(data->dok), ret);
+ return ret;
+ }
+ }
+
+ if (data->uok) {
+ ret = devm_request_threaded_irq(dev, gpiod_to_irq(data->uok),
+ NULL, max8903_usbin,
+ IRQF_TRIGGER_FALLING |
+ IRQF_TRIGGER_RISING | IRQF_ONESHOT,
+ "MAX8903 USB IN", data);
+ if (ret) {
+ dev_err(dev, "Cannot request irq %d for USB (%d)\n",
+ gpiod_to_irq(data->uok), ret);
+ return ret;
+ }
+ }
+
+ if (data->flt) {
+ ret = devm_request_threaded_irq(dev, gpiod_to_irq(data->flt),
+ NULL, max8903_fault,
+ IRQF_TRIGGER_FALLING |
+ IRQF_TRIGGER_RISING | IRQF_ONESHOT,
+ "MAX8903 Fault", data);
+ if (ret) {
+ dev_err(dev, "Cannot request irq %d for Fault (%d)\n",
+ gpiod_to_irq(data->flt), ret);
+ return ret;
+ }
+ }
+
+ return 0;
+}
+
+static const struct of_device_id max8903_match_ids[] = {
+ { .compatible = "maxim,max8903", },
+ { /* sentinel */ }
+};
+MODULE_DEVICE_TABLE(of, max8903_match_ids);
+
+static struct platform_driver max8903_driver = {
+ .probe = max8903_probe,
+ .driver = {
+ .name = "max8903-charger",
+ .of_match_table = max8903_match_ids
+ },
+};
+
+module_platform_driver(max8903_driver);
+
+MODULE_LICENSE("GPL");
+MODULE_DESCRIPTION("MAX8903 Charger Driver");
+MODULE_AUTHOR("MyungJoo Ham <myungjoo.ham@samsung.com>");
+MODULE_ALIAS("platform:max8903-charger");