4 files changed, 457 insertions, 0 deletions

diff --git a/drivers/power/Kconfig b/drivers/power/Kconfig
index 52a462fc6b84..1f50ebcc6399 100644
--- a/drivers/power/Kconfig
+++ b/drivers/power/Kconfig
@@ -203,6 +203,14 @@ config CHARGER_ISP1704
           Say Y to enable support for USB Charger Detection with
           ISP1707/ISP1704 USB transceivers.
 
+config CHARGER_MAX8903
+        tristate "MAX8903 Battery DC-DC Charger for USB and Adapter Power"
+        help
+          Say Y to enable support for the MAX8903 DC-DC charger and sysfs.
+          The driver supports controlling charger-enable and current-limit
+          pins based on the status of charger connections with interrupt
+          handlers.
+
 config CHARGER_TWL4030
         tristate "OMAP TWL4030 BCI charger driver"
         depends on TWL4030_CORE
diff --git a/drivers/power/Makefile b/drivers/power/Makefile
index 8385bfae8728..8fcd93ff2353 100644
--- a/drivers/power/Makefile
+++ b/drivers/power/Makefile
@@ -32,5 +32,6 @@ obj-$(CONFIG_CHARGER_PCF50633)	+= pcf50633-charger.o
 obj-$(CONFIG_BATTERY_JZ4740)    += jz4740-battery.o
 obj-$(CONFIG_BATTERY_INTEL_MID) += intel_mid_battery.o
 obj-$(CONFIG_CHARGER_ISP1704)   += isp1704_charger.o
+obj-$(CONFIG_CHARGER_MAX8903)   += max8903_charger.o
 obj-$(CONFIG_CHARGER_TWL4030)   += twl4030_charger.o
 obj-$(CONFIG_CHARGER_GPIO)      += gpio-charger.o
diff --git a/drivers/power/max8903_charger.c b/drivers/power/max8903_charger.c
new file mode 100644
index 000000000000..33ff0e37809e
--- /dev/null
+++ b/drivers/power/max8903_charger.c
@@ -0,0 +1,391 @@
+/*
+ * max8903_charger.c - Maxim 8903 USB/Adapter Charger Driver
+ *
+ * Copyright (C) 2011 Samsung Electronics
+ * MyungJoo Ham <myungjoo.ham@samsung.com>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
+ *
+ */
+
+#include <linux/gpio.h>
+#include <linux/interrupt.h>
+#include <linux/slab.h>
+#include <linux/power_supply.h>
+#include <linux/platform_device.h>
+#include <linux/power/max8903_charger.h>
+
+struct max8903_data {
+        struct max8903_pdata *pdata;
+        struct device *dev;
+        struct power_supply psy;
+        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 = container_of(psy,
+                        struct max8903_data, psy);
+
+        switch (psp) {
+        case POWER_SUPPLY_PROP_STATUS:
+                val->intval = POWER_SUPPLY_STATUS_UNKNOWN;
+                if (data->pdata->chg) {
+                        if (gpio_get_value(data->pdata->chg) == 0)
+                                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;
+        struct max8903_pdata *pdata = data->pdata;
+        bool ta_in;
+        enum power_supply_type old_type;
+
+        ta_in = gpio_get_value(pdata->dok) ? false : true;
+
+        if (ta_in == data->ta_in)
+                return IRQ_HANDLED;
+
+        data->ta_in = ta_in;
+
+        /* Set Current-Limit-Mode 1:DC 0:USB */
+        if (pdata->dcm)
+                gpio_set_value(pdata->dcm, ta_in ? 1 : 0);
+
+        /* Charger Enable / Disable (cen is negated) */
+        if (pdata->cen)
+                gpio_set_value(pdata->cen, ta_in ? 0 :
+                                (data->usb_in ? 0 : 1));
+
+        dev_dbg(data->dev, "TA(DC-IN) Charger %s.\n", ta_in ?
+                        "Connected" : "Disconnected");
+
+        old_type = data->psy.type;
+
+        if (data->ta_in)
+                data->psy.type = POWER_SUPPLY_TYPE_MAINS;
+        else if (data->usb_in)
+                data->psy.type = POWER_SUPPLY_TYPE_USB;
+        else
+                data->psy.type = POWER_SUPPLY_TYPE_BATTERY;
+
+        if (old_type != data->psy.type)
+                power_supply_changed(&data->psy);
+
+        return IRQ_HANDLED;
+}
+
+static irqreturn_t max8903_usbin(int irq, void *_data)
+{
+        struct max8903_data *data = _data;
+        struct max8903_pdata *pdata = data->pdata;
+        bool usb_in;
+        enum power_supply_type old_type;
+
+        usb_in = gpio_get_value(pdata->uok) ? false : true;
+
+        if (usb_in == data->usb_in)
+                return IRQ_HANDLED;
+
+        data->usb_in = usb_in;
+
+        /* Do not touch Current-Limit-Mode */
+
+        /* Charger Enable / Disable (cen is negated) */
+        if (pdata->cen)
+                gpio_set_value(pdata->cen, usb_in ? 0 :
+                                (data->ta_in ? 0 : 1));
+
+        dev_dbg(data->dev, "USB Charger %s.\n", usb_in ?
+                        "Connected" : "Disconnected");
+
+        old_type = data->psy.type;
+
+        if (data->ta_in)
+                data->psy.type = POWER_SUPPLY_TYPE_MAINS;
+        else if (data->usb_in)
+                data->psy.type = POWER_SUPPLY_TYPE_USB;
+        else
+                data->psy.type = POWER_SUPPLY_TYPE_BATTERY;
+
+        if (old_type != data->psy.type)
+                power_supply_changed(&data->psy);
+
+        return IRQ_HANDLED;
+}
+
+static irqreturn_t max8903_fault(int irq, void *_data)
+{
+        struct max8903_data *data = _data;
+        struct max8903_pdata *pdata = data->pdata;
+        bool fault;
+
+        fault = gpio_get_value(pdata->flt) ? false : true;
+
+        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 __devinit int max8903_probe(struct platform_device *pdev)
+{
+        struct max8903_data *data;
+        struct device *dev = &pdev->dev;
+        struct max8903_pdata *pdata = pdev->dev.platform_data;
+        int ret = 0;
+        int gpio;
+        int ta_in = 0;
+        int usb_in = 0;
+
+        data = kzalloc(sizeof(struct max8903_data), GFP_KERNEL);
+        if (data == NULL) {
+                dev_err(dev, "Cannot allocate memory.\n");
+                return -ENOMEM;
+        }
+        data->pdata = pdata;
+        data->dev = dev;
+        platform_set_drvdata(pdev, data);
+
+        if (pdata->dc_valid == false && pdata->usb_valid == false) {
+                dev_err(dev, "No valid power sources.\n");
+                ret = -EINVAL;
+                goto err;
+        }
+
+        if (pdata->dc_valid) {
+                if (pdata->dok && gpio_is_valid(pdata->dok) &&
+                                pdata->dcm && gpio_is_valid(pdata->dcm)) {
+                        gpio = pdata->dok; /* PULL_UPed Interrupt */
+                        ta_in = gpio_get_value(gpio) ? 0 : 1;
+
+                        gpio = pdata->dcm; /* Output */
+                        gpio_set_value(gpio, ta_in);
+                } else {
+                        dev_err(dev, "When DC is wired, DOK and DCM should"
+                                        " be wired as well.\n");
+                        ret = -EINVAL;
+                        goto err;
+                }
+        } else {
+                if (pdata->dcm) {
+                        if (gpio_is_valid(pdata->dcm))
+                                gpio_set_value(pdata->dcm, 0);
+                        else {
+                                dev_err(dev, "Invalid pin: dcm.\n");
+                                ret = -EINVAL;
+                                goto err;
+                        }
+                }
+        }
+
+        if (pdata->usb_valid) {
+                if (pdata->uok && gpio_is_valid(pdata->uok)) {
+                        gpio = pdata->uok;
+                        usb_in = gpio_get_value(gpio) ? 0 : 1;
+                } else {
+                        dev_err(dev, "When USB is wired, UOK should be wired."
+                                        "as well.\n");
+                        ret = -EINVAL;
+                        goto err;
+                }
+        }
+
+        if (pdata->cen) {
+                if (gpio_is_valid(pdata->cen)) {
+                        gpio_set_value(pdata->cen, (ta_in || usb_in) ? 0 : 1);
+                } else {
+                        dev_err(dev, "Invalid pin: cen.\n");
+                        ret = -EINVAL;
+                        goto err;
+                }
+        }
+
+        if (pdata->chg) {
+                if (!gpio_is_valid(pdata->chg)) {
+                        dev_err(dev, "Invalid pin: chg.\n");
+                        ret = -EINVAL;
+                        goto err;
+                }
+        }
+
+        if (pdata->flt) {
+                if (!gpio_is_valid(pdata->flt)) {
+                        dev_err(dev, "Invalid pin: flt.\n");
+                        ret = -EINVAL;
+                        goto err;
+                }
+        }
+
+        if (pdata->usus) {
+                if (!gpio_is_valid(pdata->usus)) {
+                        dev_err(dev, "Invalid pin: usus.\n");
+                        ret = -EINVAL;
+                        goto err;
+                }
+        }
+
+        data->fault = false;
+        data->ta_in = ta_in;
+        data->usb_in = usb_in;
+
+        data->psy.name = "max8903_charger";
+        data->psy.type = (ta_in) ? POWER_SUPPLY_TYPE_MAINS :
+                        ((usb_in) ? POWER_SUPPLY_TYPE_USB :
+                         POWER_SUPPLY_TYPE_BATTERY);
+        data->psy.get_property = max8903_get_property;
+        data->psy.properties = max8903_charger_props;
+        data->psy.num_properties = ARRAY_SIZE(max8903_charger_props);
+
+        ret = power_supply_register(dev, &data->psy);
+        if (ret) {
+                dev_err(dev, "failed: power supply register.\n");
+                goto err;
+        }
+
+        if (pdata->dc_valid) {
+                ret = request_threaded_irq(gpio_to_irq(pdata->dok),
+                                NULL, max8903_dcin,
+                                IRQF_TRIGGER_FALLING | IRQF_TRIGGER_RISING,
+                                "MAX8903 DC IN", data);
+                if (ret) {
+                        dev_err(dev, "Cannot request irq %d for DC (%d)\n",
+                                        gpio_to_irq(pdata->dok), ret);
+                        goto err_psy;
+                }
+        }
+
+        if (pdata->usb_valid) {
+                ret = request_threaded_irq(gpio_to_irq(pdata->uok),
+                                NULL, max8903_usbin,
+                                IRQF_TRIGGER_FALLING | IRQF_TRIGGER_RISING,
+                                "MAX8903 USB IN", data);
+                if (ret) {
+                        dev_err(dev, "Cannot request irq %d for USB (%d)\n",
+                                        gpio_to_irq(pdata->uok), ret);
+                        goto err_dc_irq;
+                }
+        }
+
+        if (pdata->flt) {
+                ret = request_threaded_irq(gpio_to_irq(pdata->flt),
+                                NULL, max8903_fault,
+                                IRQF_TRIGGER_FALLING | IRQF_TRIGGER_RISING,
+                                "MAX8903 Fault", data);
+                if (ret) {
+                        dev_err(dev, "Cannot request irq %d for Fault (%d)\n",
+                                        gpio_to_irq(pdata->flt), ret);
+                        goto err_usb_irq;
+                }
+        }
+
+        return 0;
+
+err_usb_irq:
+        if (pdata->usb_valid)
+                free_irq(gpio_to_irq(pdata->uok), data);
+err_dc_irq:
+        if (pdata->dc_valid)
+                free_irq(gpio_to_irq(pdata->dok), data);
+err_psy:
+        power_supply_unregister(&data->psy);
+err:
+        kfree(data);
+        return ret;
+}
+
+static __devexit int max8903_remove(struct platform_device *pdev)
+{
+        struct max8903_data *data = platform_get_drvdata(pdev);
+
+        if (data) {
+                struct max8903_pdata *pdata = data->pdata;
+
+                if (pdata->flt)
+                        free_irq(gpio_to_irq(pdata->flt), data);
+                if (pdata->usb_valid)
+                        free_irq(gpio_to_irq(pdata->uok), data);
+                if (pdata->dc_valid)
+                        free_irq(gpio_to_irq(pdata->dok), data);
+                power_supply_unregister(&data->psy);
+                kfree(data);
+        }
+
+        return 0;
+}
+
+static struct platform_driver max8903_driver = {
+        .probe  = max8903_probe,
+        .remove = __devexit_p(max8903_remove),
+        .driver = {
+                .name   = "max8903-charger",
+                .owner  = THIS_MODULE,
+        },
+};
+
+static int __init max8903_init(void)
+{
+        return platform_driver_register(&max8903_driver);
+}
+module_init(max8903_init);
+
+static void __exit max8903_exit(void)
+{
+        platform_driver_unregister(&max8903_driver);
+}
+module_exit(max8903_exit);
+
+MODULE_LICENSE("GPL");
+MODULE_DESCRIPTION("MAX8903 Charger Driver");
+MODULE_AUTHOR("MyungJoo Ham <myungjoo.ham@samsung.com>");
+MODULE_ALIAS("max8903-charger");
diff --git a/include/linux/power/max8903_charger.h b/include/linux/power/max8903_charger.h
new file mode 100644
index 000000000000..24f51db8a83f
--- /dev/null
+++ b/include/linux/power/max8903_charger.h
@@ -0,0 +1,57 @@
+/*
+ * max8903_charger.h - Maxim 8903 USB/Adapter Charger Driver
+ *
+ * Copyright (C) 2011 Samsung Electronics
+ * MyungJoo Ham <myungjoo.ham@samsung.com>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
+ *
+ */
+
+#ifndef __MAX8903_CHARGER_H__
+#define __MAX8903_CHARGER_H__
+
+struct max8903_pdata {
+        /*
+         * GPIOs
+         * cen, chg, flt, and usus are optional.
+         * dok, dcm, and uok are not optional depending on the status of
+         * dc_valid and usb_valid.
+         */
+        int cen;        /* Charger Enable input */
+        int dok;        /* DC(Adapter) Power OK output */
+        int uok;        /* USB Power OK output */
+        int chg;        /* Charger status output */
+        int flt;        /* Fault output */
+        int dcm;        /* Current-Limit Mode input (1: DC, 2: USB) */
+        int usus;       /* USB Suspend Input (1: suspended) */
+
+        /*
+         * DC(Adapter/TA) is wired
+         * When dc_valid is true,
+         *      dok and dcm should be valid.
+         *
+         * At least one of dc_valid or usb_valid should be true.
+         */
+        bool dc_valid;
+        /*
+         * USB is wired
+         * When usb_valid is true,
+         *      uok should be valid.
+         */
+        bool usb_valid;
+};
+
+#endif /* __MAX8903_CHARGER_H__ */