power: add driver for battery reading on iPaq h3xxx

This adds a driver for reading the battery status of the
battery connected to the Atmel microcontroller on the
iPAQ h3xxx series.

Based on a driver from handhelds.org 2.6.21 kernel, written
by Alessandro GARDICH.

Signed-off-by: Dmitry Artamonow <mad_soft@inbox.ru>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Sebastian Reichel <sre@kernel.org>

3 files changed, 298 insertions, 0 deletions

diff --git a/drivers/power/Kconfig b/drivers/power/Kconfig
index ba6975123071..73cfcdf28a36 100644
--- a/drivers/power/Kconfig
+++ b/drivers/power/Kconfig
@@ -137,6 +137,13 @@ config BATTERY_COLLIE
           Say Y to enable support for the battery on the Sharp Zaurus
           SL-5500 (collie) models.
 
+config BATTERY_IPAQ_MICRO
+        tristate "iPAQ Atmel Micro ASIC battery driver"
+        depends on MFD_IPAQ_MICRO
+        help
+          Choose this option if you want to monitor battery status on
+          Compaq/HP iPAQ h3100 and h3600.
+
 config BATTERY_WM97XX
         bool "WM97xx generic battery driver"
         depends on TOUCHSCREEN_WM97XX=y
diff --git a/drivers/power/Makefile b/drivers/power/Makefile
index ee54a3e4c90a..dfa894273926 100644
--- a/drivers/power/Makefile
+++ b/drivers/power/Makefile
@@ -25,6 +25,7 @@ obj-$(CONFIG_BATTERY_PMU)	+= pmu_battery.o
 obj-$(CONFIG_BATTERY_OLPC)      += olpc_battery.o
 obj-$(CONFIG_BATTERY_TOSA)      += tosa_battery.o
 obj-$(CONFIG_BATTERY_COLLIE)    += collie_battery.o
+obj-$(CONFIG_BATTERY_IPAQ_MICRO) += ipaq_micro_battery.o
 obj-$(CONFIG_BATTERY_WM97XX)    += wm97xx_battery.o
 obj-$(CONFIG_BATTERY_SBS)       += sbs-battery.o
 obj-$(CONFIG_BATTERY_BQ27x00)   += bq27x00_battery.o
diff --git a/drivers/power/ipaq_micro_battery.c b/drivers/power/ipaq_micro_battery.c
new file mode 100644
index 000000000000..54632eabf420
--- /dev/null
+++ b/drivers/power/ipaq_micro_battery.c
@@ -0,0 +1,290 @@
+/*
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ *
+ * h3xxx atmel micro companion support, battery subdevice
+ * based on previous kernel 2.4 version
+ * Author : Alessandro Gardich <gremlin@gremlin.it>
+ * Author : Linus Walleij <linus.walleij@linaro.org>
+ *
+ */
+
+#include <linux/module.h>
+#include <linux/init.h>
+#include <linux/platform_device.h>
+#include <linux/mfd/ipaq-micro.h>
+#include <linux/power_supply.h>
+#include <linux/workqueue.h>
+
+#define BATT_PERIOD 100000 /* 100 seconds in milliseconds */
+
+#define MICRO_BATT_CHEM_ALKALINE        0x01
+#define MICRO_BATT_CHEM_NICD            0x02
+#define MICRO_BATT_CHEM_NIMH            0x03
+#define MICRO_BATT_CHEM_LION            0x04
+#define MICRO_BATT_CHEM_LIPOLY          0x05
+#define MICRO_BATT_CHEM_NOT_INSTALLED   0x06
+#define MICRO_BATT_CHEM_UNKNOWN         0xff
+
+#define MICRO_BATT_STATUS_HIGH          0x01
+#define MICRO_BATT_STATUS_LOW           0x02
+#define MICRO_BATT_STATUS_CRITICAL      0x04
+#define MICRO_BATT_STATUS_CHARGING      0x08
+#define MICRO_BATT_STATUS_CHARGEMAIN    0x10
+#define MICRO_BATT_STATUS_DEAD          0x20 /* Battery will not charge */
+#define MICRO_BATT_STATUS_NOTINSTALLED  0x20 /* For expansion pack batteries */
+#define MICRO_BATT_STATUS_FULL          0x40 /* Battery fully charged */
+#define MICRO_BATT_STATUS_NOBATTERY     0x80
+#define MICRO_BATT_STATUS_UNKNOWN       0xff
+
+struct micro_battery {
+        struct ipaq_micro *micro;
+        struct workqueue_struct *wq;
+        struct delayed_work update;
+        u8 ac;
+        u8 chemistry;
+        unsigned int voltage;
+        u16 temperature;
+        u8 flag;
+};
+
+static void micro_battery_work(struct work_struct *work)
+{
+        struct micro_battery *mb = container_of(work,
+                                struct micro_battery, update.work);
+        struct ipaq_micro_msg msg_battery = {
+                .id = MSG_BATTERY,
+        };
+        struct ipaq_micro_msg msg_sensor = {
+                .id = MSG_THERMAL_SENSOR,
+        };
+
+        /* First send battery message */
+        ipaq_micro_tx_msg_sync(mb->micro, &msg_battery);
+        if (msg_battery.rx_len < 4)
+                pr_info("ERROR");
+
+        /*
+         * Returned message format:
+         * byte 0:   0x00 = Not plugged in
+         *           0x01 = AC adapter plugged in
+         * byte 1:   chemistry
+         * byte 2:   voltage LSB
+         * byte 3:   voltage MSB
+         * byte 4:   flags
+         * byte 5-9: same for battery 2
+         */
+        mb->ac = msg_battery.rx_data[0];
+        mb->chemistry = msg_battery.rx_data[1];
+        mb->voltage = ((((unsigned short)msg_battery.rx_data[3] << 8) +
+                        msg_battery.rx_data[2]) * 5000L) * 1000 / 1024;
+        mb->flag = msg_battery.rx_data[4];
+
+        if (msg_battery.rx_len == 9)
+                pr_debug("second battery ignored\n");
+
+        /* Then read the sensor */
+        ipaq_micro_tx_msg_sync(mb->micro, &msg_sensor);
+        mb->temperature = msg_sensor.rx_data[1] << 8 | msg_sensor.rx_data[0];
+
+        queue_delayed_work(mb->wq, &mb->update, msecs_to_jiffies(BATT_PERIOD));
+}
+
+static int get_capacity(struct power_supply *b)
+{
+        struct micro_battery *mb = dev_get_drvdata(b->dev->parent);
+
+        switch (mb->flag & 0x07) {
+        case MICRO_BATT_STATUS_HIGH:
+                return 100;
+                break;
+        case MICRO_BATT_STATUS_LOW:
+                return 50;
+                break;
+        case MICRO_BATT_STATUS_CRITICAL:
+                return 5;
+                break;
+        default:
+                break;
+        }
+        return 0;
+}
+
+static int get_status(struct power_supply *b)
+{
+        struct micro_battery *mb = dev_get_drvdata(b->dev->parent);
+
+        if (mb->flag == MICRO_BATT_STATUS_UNKNOWN)
+                return POWER_SUPPLY_STATUS_UNKNOWN;
+
+        if (mb->flag & MICRO_BATT_STATUS_FULL)
+                return POWER_SUPPLY_STATUS_FULL;
+
+        if ((mb->flag & MICRO_BATT_STATUS_CHARGING) ||
+                (mb->flag & MICRO_BATT_STATUS_CHARGEMAIN))
+                return POWER_SUPPLY_STATUS_CHARGING;
+
+        return POWER_SUPPLY_STATUS_DISCHARGING;
+}
+
+static int micro_batt_get_property(struct power_supply *b,
+                                        enum power_supply_property psp,
+                                        union power_supply_propval *val)
+{
+        struct micro_battery *mb = dev_get_drvdata(b->dev->parent);
+
+        switch (psp) {
+        case POWER_SUPPLY_PROP_TECHNOLOGY:
+                switch (mb->chemistry) {
+                case MICRO_BATT_CHEM_NICD:
+                        val->intval = POWER_SUPPLY_TECHNOLOGY_NiCd;
+                        break;
+                case MICRO_BATT_CHEM_NIMH:
+                        val->intval = POWER_SUPPLY_TECHNOLOGY_NiMH;
+                        break;
+                case MICRO_BATT_CHEM_LION:
+                        val->intval = POWER_SUPPLY_TECHNOLOGY_LION;
+                        break;
+                case MICRO_BATT_CHEM_LIPOLY:
+                        val->intval = POWER_SUPPLY_TECHNOLOGY_LIPO;
+                        break;
+                default:
+                        val->intval = POWER_SUPPLY_TECHNOLOGY_UNKNOWN;
+                        break;
+                };
+                break;
+        case POWER_SUPPLY_PROP_STATUS:
+                val->intval = get_status(b);
+                break;
+        case POWER_SUPPLY_PROP_VOLTAGE_MAX_DESIGN:
+                val->intval = 4700000;
+                break;
+        case POWER_SUPPLY_PROP_CAPACITY:
+                val->intval = get_capacity(b);
+                break;
+        case POWER_SUPPLY_PROP_TEMP:
+                val->intval = mb->temperature;
+                break;
+        case POWER_SUPPLY_PROP_VOLTAGE_NOW:
+                val->intval = mb->voltage;
+                break;
+        default:
+                return -EINVAL;
+        };
+
+        return 0;
+}
+
+static int micro_ac_get_property(struct power_supply *b,
+                                 enum power_supply_property psp,
+                                 union power_supply_propval *val)
+{
+        struct micro_battery *mb = dev_get_drvdata(b->dev->parent);
+
+        switch (psp) {
+        case POWER_SUPPLY_PROP_ONLINE:
+                val->intval = mb->ac;
+                break;
+        default:
+                return -EINVAL;
+        };
+
+        return 0;
+}
+
+static enum power_supply_property micro_batt_power_props[] = {
+        POWER_SUPPLY_PROP_TECHNOLOGY,
+        POWER_SUPPLY_PROP_STATUS,
+        POWER_SUPPLY_PROP_VOLTAGE_MAX_DESIGN,
+        POWER_SUPPLY_PROP_CAPACITY,
+        POWER_SUPPLY_PROP_TEMP,
+        POWER_SUPPLY_PROP_VOLTAGE_NOW,
+};
+
+static struct power_supply micro_batt_power = {
+        .name                   = "main-battery",
+        .type                   = POWER_SUPPLY_TYPE_BATTERY,
+        .properties             = micro_batt_power_props,
+        .num_properties         = ARRAY_SIZE(micro_batt_power_props),
+        .get_property           = micro_batt_get_property,
+        .use_for_apm            = 1,
+};
+
+static enum power_supply_property micro_ac_power_props[] = {
+        POWER_SUPPLY_PROP_ONLINE,
+};
+
+static struct power_supply micro_ac_power = {
+        .name                   = "ac",
+        .type                   = POWER_SUPPLY_TYPE_MAINS,
+        .properties             = micro_ac_power_props,
+        .num_properties         = ARRAY_SIZE(micro_ac_power_props),
+        .get_property           = micro_ac_get_property,
+};
+
+static int micro_batt_probe(struct platform_device *pdev)
+{
+        struct micro_battery *mb;
+
+        mb = devm_kzalloc(&pdev->dev, sizeof(*mb), GFP_KERNEL);
+        if (!mb)
+                return -ENOMEM;
+
+        mb->micro = dev_get_drvdata(pdev->dev.parent);
+        mb->wq = create_singlethread_workqueue("ipaq-battery-wq");
+        INIT_DELAYED_WORK(&mb->update, micro_battery_work);
+        platform_set_drvdata(pdev, mb);
+        queue_delayed_work(mb->wq, &mb->update, 1);
+        power_supply_register(&pdev->dev, &micro_batt_power);
+        power_supply_register(&pdev->dev, &micro_ac_power);
+
+        dev_info(&pdev->dev, "iPAQ micro battery driver\n");
+        return 0;
+}
+
+static int micro_batt_remove(struct platform_device *pdev)
+
+{
+        struct micro_battery *mb = platform_get_drvdata(pdev);
+
+        power_supply_unregister(&micro_ac_power);
+        power_supply_unregister(&micro_batt_power);
+        cancel_delayed_work_sync(&mb->update);
+
+        return 0;
+}
+
+static int micro_batt_suspend(struct device *dev)
+{
+        struct micro_battery *mb = dev_get_drvdata(dev);
+
+        cancel_delayed_work_sync(&mb->update);
+        return 0;
+}
+
+static int micro_batt_resume(struct device *dev)
+{
+        struct micro_battery *mb = dev_get_drvdata(dev);
+
+        queue_delayed_work(mb->wq, &mb->update, msecs_to_jiffies(BATT_PERIOD));
+        return 0;
+}
+
+static const struct dev_pm_ops micro_batt_dev_pm_ops = {
+        SET_SYSTEM_SLEEP_PM_OPS(micro_batt_suspend, micro_batt_resume)
+};
+
+struct platform_driver micro_batt_device_driver = {
+        .driver         = {
+                .name   = "ipaq-micro-battery",
+                .pm     = &micro_batt_dev_pm_ops,
+        },
+        .probe          = micro_batt_probe,
+        .remove         = micro_batt_remove,
+};
+module_platform_driver(micro_batt_device_driver);
+
+MODULE_LICENSE("GPL");
+MODULE_DESCRIPTION("driver for iPAQ Atmel micro battery");
+MODULE_ALIAS("platform:battery-ipaq-micro");