[PATCH] power: add poodle battery driver

[Dmitry Eremin-Solenikov <dbaryshkov@gmail.com>]

Add a driver supporting battery charging on Sharp SL-5600 (poodle).
Voltage and temperature readings are provided through add7846 hwmon
interface. Battery voltage is in1_input (mV) and temp in in0_input
(values unknown, but should be less than 2441).

Signed-off-by: Dmitry Eremin-Solenikov <dbaryshkov@gmail.com>
---
 drivers/power/Kconfig          |   7 ++
 drivers/power/Makefile         |   1 +
 drivers/power/poodle_battery.c | 250 +++++++++++++++++++++++++++++++++++++++++
 3 files changed, 258 insertions(+)
 create mode 100644 drivers/power/poodle_battery.c

diff --git a/drivers/power/Kconfig b/drivers/power/Kconfig
index 27b751b..678f23e 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_POODLE
+	tristate "Sharp SL-5600 (poodle) battery"
+	depends on MACH_POODLE
+	help
+	  Say Y to enable support for the battery on the Sharp Zaurus
+	  SL-5600 (poodle) models.
+
 config BATTERY_IPAQ_MICRO
 	tristate "iPAQ Atmel Micro ASIC battery driver"
 	depends on MFD_IPAQ_MICRO
diff --git a/drivers/power/Makefile b/drivers/power/Makefile
index 36f9e0d..ff3e793 100644
--- a/drivers/power/Makefile
+++ b/drivers/power/Makefile
@@ -26,6 +26,7 @@ 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-$(CONFIG_BATTERY_POODLE)	+= poodle_battery.o
 obj-$(CONFIG_BATTERY_IPAQ_MICRO) += ipaq_micro_battery.o
 obj-$(CONFIG_BATTERY_WM97XX)	+= wm97xx_battery.o
 obj-$(CONFIG_BATTERY_SBS)	+= sbs-battery.o
diff --git a/drivers/power/poodle_battery.c b/drivers/power/poodle_battery.c
new file mode 100644
index 0000000..ad96e13
--- /dev/null
+++ b/drivers/power/poodle_battery.c
@@ -0,0 +1,250 @@
+/*
+ * Battery handler for Sharp SL-5600 Poodle device
+ *
+ * Copyright (c) 2014 Dmitry Eremin-Solenikov
+ *
+ * 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.
+ */
+#include <linux/delay.h>
+#include <linux/gpio.h>
+#include <linux/interrupt.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/platform_device.h>
+#include <linux/power_supply.h>
+
+#include <mach/poodle.h>
+
+struct poodle_bat {
+	int status;
+	struct power_supply psy;
+
+	struct mutex work_lock; /* protects data */
+
+	bool (*is_present)(struct poodle_bat *bat);
+	int technology;
+};
+
+static DEFINE_MUTEX(bat_lock); /* protects gpio pins */
+static struct work_struct bat_work;
+
+static struct poodle_bat poodle_bat_main;
+
+static int poodle_bat_get_property(struct power_supply *psy,
+			    enum power_supply_property psp,
+			    union power_supply_propval *val)
+{
+	int ret = 0;
+	struct poodle_bat *bat = container_of(psy, struct poodle_bat, psy);
+
+	if (bat->is_present && !bat->is_present(bat)
+			&& psp != POWER_SUPPLY_PROP_PRESENT) {
+		return -ENODEV;
+	}
+
+	switch (psp) {
+	case POWER_SUPPLY_PROP_STATUS:
+		val->intval = bat->status;
+		break;
+	case POWER_SUPPLY_PROP_TECHNOLOGY:
+		val->intval = bat->technology;
+		break;
+	case POWER_SUPPLY_PROP_PRESENT:
+		val->intval = bat->is_present ? bat->is_present(bat) : 1;
+		break;
+	default:
+		ret = -EINVAL;
+		break;
+	}
+	return ret;
+}
+
+static bool poodle_bat_is_present(struct poodle_bat *bat)
+{
+	return gpio_get_value(POODLE_GPIO_BAT_COVER);
+}
+
+static void poodle_bat_external_power_changed(struct power_supply *psy)
+{
+	schedule_work(&bat_work);
+}
+
+static irqreturn_t poodle_bat_gpio_isr(int irq, void *data)
+{
+	pr_info("poodle_bat_gpio irq\n");
+	schedule_work(&bat_work);
+	return IRQ_HANDLED;
+}
+
+static void poodle_bat_update(struct poodle_bat *bat)
+{
+	int old;
+	struct power_supply *psy = &bat->psy;
+
+	mutex_lock(&bat->work_lock);
+
+	old = bat->status;
+
+	if (bat->is_present && !bat->is_present(bat)) {
+		pr_info("%s not present\n", psy->name);
+		bat->status = POWER_SUPPLY_STATUS_UNKNOWN;
+		gpio_set_value(POODLE_GPIO_JK_B, 0);
+		gpio_set_value(POODLE_GPIO_CHRG_ON, 0);
+	} else if (power_supply_am_i_supplied(psy)) {
+		gpio_set_value(POODLE_GPIO_JK_B, 1);
+		if (bat->status == POWER_SUPPLY_STATUS_DISCHARGING) {
+			gpio_set_value(POODLE_GPIO_CHRG_ON, 1);
+			msleep(20);
+		}
+
+		if (gpio_get_value(POODLE_GPIO_CHRG_FULL)) {
+			gpio_set_value(POODLE_GPIO_CHRG_ON, 0);
+			bat->status = POWER_SUPPLY_STATUS_FULL;
+		} else {
+			gpio_set_value(POODLE_GPIO_CHRG_ON, 1);
+			bat->status = POWER_SUPPLY_STATUS_CHARGING;
+		}
+	} else {
+		gpio_set_value(POODLE_GPIO_JK_B, 0);
+		gpio_set_value(POODLE_GPIO_CHRG_ON, 0);
+		bat->status = POWER_SUPPLY_STATUS_DISCHARGING;
+	}
+
+	if (old != bat->status)
+		power_supply_changed(psy);
+
+	mutex_unlock(&bat->work_lock);
+}
+
+static void poodle_bat_work(struct work_struct *work)
+{
+	poodle_bat_update(&poodle_bat_main);
+}
+
+static enum power_supply_property poodle_bat_main_props[] = {
+	POWER_SUPPLY_PROP_STATUS,
+	POWER_SUPPLY_PROP_TECHNOLOGY,
+	POWER_SUPPLY_PROP_PRESENT,
+};
+
+static struct poodle_bat poodle_bat_main = {
+	.status = POWER_SUPPLY_STATUS_DISCHARGING,
+	.psy = {
+		.name		= "main-battery",
+		.type		= POWER_SUPPLY_TYPE_BATTERY,
+		.properties	= poodle_bat_main_props,
+		.num_properties	= ARRAY_SIZE(poodle_bat_main_props),
+		.get_property	= poodle_bat_get_property,
+		.external_power_changed = poodle_bat_external_power_changed,
+		.use_for_apm	= 1,
+	},
+
+	.is_present = poodle_bat_is_present,
+
+	.technology = POWER_SUPPLY_TECHNOLOGY_LIPO,
+};
+
+static struct gpio poodle_batt_gpios[] = {
+	{ POODLE_GPIO_BAT_COVER,    GPIOF_IN,		"main battery cover" },
+	{ POODLE_GPIO_CHRG_FULL,    GPIOF_IN,		"main battery full" },
+	{ POODLE_GPIO_JK_B,	    GPIOF_OUT_INIT_LOW,	"main charge on" },
+	{ POODLE_GPIO_CHRG_ON,	    GPIOF_OUT_INIT_LOW,	"main charge on" },
+	{ POODLE_GPIO_BYPASS_ON,    GPIOF_OUT_INIT_LOW,	"main charge bypass" },
+	/* on for now */
+	{ POODLE_GPIO_ADC_TEMP_ON,  GPIOF_OUT_INIT_HIGH, "main battery temp" },
+};
+
+#ifdef CONFIG_PM
+static int poodle_battery_suspend(struct device *dev)
+{
+	/* flush all pending status updates */
+	flush_work(&bat_work);
+	return 0;
+}
+
+static int poodle_battery_resume(struct device *dev)
+{
+	/* things may have changed while we were away */
+	schedule_work(&bat_work);
+	return 0;
+}
+
+static SIMPLE_DEV_PM_OPS(poodle_battery_pm,
+		poodle_battery_suspend,
+		poodle_battery_resume);
+
+#define POODLE_BATTERY_PM (&poodle_battery_pm)
+
+#else
+#define POODLE_BATTERY_PM NULL
+#endif
+
+static int poodle_battery_probe(struct platform_device *dev)
+{
+	int ret;
+
+	ret = gpio_request_array(poodle_batt_gpios,
+				 ARRAY_SIZE(poodle_batt_gpios));
+	if (ret)
+		return ret;
+
+	mutex_init(&poodle_bat_main.work_lock);
+
+	INIT_WORK(&bat_work, poodle_bat_work);
+
+	ret = power_supply_register(&dev->dev, &poodle_bat_main.psy);
+	if (ret)
+		goto err_psy_reg_main;
+
+	ret = devm_request_irq(&dev->dev, gpio_to_irq(POODLE_GPIO_CHRG_FULL),
+				poodle_bat_gpio_isr,
+				IRQF_TRIGGER_RISING | IRQF_TRIGGER_FALLING,
+				"main full", NULL);
+	if (ret)
+		goto err_psy_irq;
+
+	ret = devm_request_irq(&dev->dev, gpio_to_irq(POODLE_GPIO_BAT_COVER),
+				poodle_bat_gpio_isr,
+				IRQF_TRIGGER_RISING | IRQF_TRIGGER_FALLING,
+				"battery cover", NULL);
+	if (ret)
+		goto err_psy_irq;
+
+	return 0;
+
+err_psy_irq:
+	power_supply_unregister(&poodle_bat_main.psy);
+
+	cancel_work_sync(&bat_work);
+err_psy_reg_main:
+	gpio_free_array(poodle_batt_gpios, ARRAY_SIZE(poodle_batt_gpios));
+
+	return ret;
+}
+
+static int poodle_battery_remove(struct platform_device *dev)
+{
+	power_supply_unregister(&poodle_bat_main.psy);
+
+	cancel_work_sync(&bat_work);
+
+	gpio_free_array(poodle_batt_gpios, ARRAY_SIZE(poodle_batt_gpios));
+
+	return 0;
+}
+
+static struct platform_driver poodle_battery_driver = {
+	.driver.name	= "poodle-battery",
+	.probe		= poodle_battery_probe,
+	.remove		= poodle_battery_remove,
+	.driver.pm	= POODLE_BATTERY_PM,
+};
+
+module_platform_driver(poodle_battery_driver);
+
+MODULE_LICENSE("GPL v2");
+MODULE_AUTHOR("Dmitry Eremin-Solenikov");
+MODULE_DESCRIPTION("Poodle battery driver");
+MODULE_ALIAS("platform:poodle-battery");
-- 
2.1.4