Add s3c-adc-battery driver

s3c-adc-battery is driver for monitoring and charging battery on
iPAQ H1930/H1940/RX1950.

It depends on s3c-adc driver to get battery voltage and current.

Signed-off-by: Vasily Khoruzhick <anarsoul@gmail.com>
Signed-off-by: Anton Vorontsov <cbouatmailru@gmail.com>

4 files changed, 474 insertions, 0 deletions

diff --git a/drivers/power/Kconfig b/drivers/power/Kconfig
index 6eae821..d1d3c70 100644
--- a/drivers/power/Kconfig
+++ b/drivers/power/Kconfig
@@ -136,6 +136,12 @@ config BATTERY_Z2
 	help
 	  Say Y to include support for the battery on the Zipit Z2.
 
+config BATTERY_S3C_ADC
+	tristate "Battery driver for Samsung ADC based monitoring"
+	depends on S3C_ADC
+	help
+	  Say Y here to enable support for iPAQ h1930/h1940/rx1950 battery
+
 config CHARGER_PCF50633
 	tristate "NXP PCF50633 MBC"
 	depends on MFD_PCF50633
diff --git a/drivers/power/Makefile b/drivers/power/Makefile
index 2b9a81d..705675a 100644
--- a/drivers/power/Makefile
+++ b/drivers/power/Makefile
@@ -33,5 +33,6 @@ obj-$(CONFIG_BATTERY_BQ27x00)	+= bq27x00_battery.o
 obj-$(CONFIG_BATTERY_DA9030)	+= da9030_battery.o
 obj-$(CONFIG_BATTERY_MAX17040)	+= max17040_battery.o
 obj-$(CONFIG_BATTERY_Z2)	+= z2_battery.o
+obj-$(CONFIG_BATTERY_S3C_ADC)	+= s3c_adc_battery.o
 obj-$(CONFIG_CHARGER_PCF50633)	+= pcf50633-charger.o
 obj-$(CONFIG_BATTERY_INTEL_MID)	+= intel_mid_battery.o
diff --git a/drivers/power/s3c_adc_battery.c b/drivers/power/s3c_adc_battery.c
new file mode 100644
index 0000000..fe16b48
--- /dev/null
+++ b/drivers/power/s3c_adc_battery.c
@@ -0,0 +1,431 @@
+/*
+ *	iPAQ h1930/h1940/rx1950 battery controler driver
+ *	Copyright (c) Vasily Khoruzhick
+ *	Based on h1940_battery.c by Arnaud Patard
+ *
+ * This file is subject to the terms and conditions of the GNU General Public
+ * License.  See the file COPYING in the main directory of this archive for
+ * more details.
+ *
+ */
+
+#include <linux/interrupt.h>
+#include <linux/platform_device.h>
+#include <linux/power_supply.h>
+#include <linux/leds.h>
+#include <linux/gpio.h>
+#include <linux/err.h>
+#include <linux/timer.h>
+#include <linux/jiffies.h>
+#include <linux/s3c_adc_battery.h>
+#include <linux/errno.h>
+#include <linux/init.h>
+
+#include <plat/adc.h>
+
+#define BAT_POLL_INTERVAL		10000 /* ms */
+#define JITTER_DELAY			500 /* ms */
+
+struct s3c_adc_bat {
+	struct power_supply		psy;
+	struct s3c_adc_client		*client;
+	struct s3c_adc_bat_pdata	*pdata;
+	int				volt_value;
+	int				cur_value;
+	unsigned int			timestamp;
+	int				level;
+	int				status;
+	int				cable_plugged:1;
+};
+
+static struct delayed_work bat_work;
+
+static void s3c_adc_bat_ext_power_changed(struct power_supply *psy)
+{
+	schedule_delayed_work(&bat_work,
+		msecs_to_jiffies(JITTER_DELAY));
+}
+
+static enum power_supply_property s3c_adc_backup_bat_props[] = {
+	POWER_SUPPLY_PROP_VOLTAGE_NOW,
+	POWER_SUPPLY_PROP_VOLTAGE_MIN,
+	POWER_SUPPLY_PROP_VOLTAGE_MAX_DESIGN,
+};
+
+static int s3c_adc_backup_bat_get_property(struct power_supply *psy,
+				enum power_supply_property psp,
+				union power_supply_propval *val)
+{
+	struct s3c_adc_bat *bat = container_of(psy, struct s3c_adc_bat, psy);
+
+	if (!bat) {
+		dev_err(psy->dev, "%s: no battery infos ?!\n", __func__);
+		return -EINVAL;
+	}
+
+	if (bat->volt_value < 0 ||
+		jiffies_to_msecs(jiffies - bat->timestamp) >
+			BAT_POLL_INTERVAL) {
+		bat->volt_value = s3c_adc_read(bat->client,
+			bat->pdata->backup_volt_channel);
+		bat->volt_value *= bat->pdata->backup_volt_mult;
+		bat->timestamp = jiffies;
+	}
+
+	switch (psp) {
+	case POWER_SUPPLY_PROP_VOLTAGE_NOW:
+		val->intval = bat->volt_value;
+		return 0;
+	case POWER_SUPPLY_PROP_VOLTAGE_MIN:
+		val->intval = bat->pdata->backup_volt_min;
+		return 0;
+	case POWER_SUPPLY_PROP_VOLTAGE_MAX_DESIGN:
+		val->intval = bat->pdata->backup_volt_max;
+		return 0;
+	default:
+		return -EINVAL;
+	}
+}
+
+static struct s3c_adc_bat backup_bat = {
+	.psy = {
+		.name		= "backup-battery",
+		.type		= POWER_SUPPLY_TYPE_BATTERY,
+		.properties	= s3c_adc_backup_bat_props,
+		.num_properties = ARRAY_SIZE(s3c_adc_backup_bat_props),
+		.get_property	= s3c_adc_backup_bat_get_property,
+		.use_for_apm	= 1,
+	},
+};
+
+static enum power_supply_property s3c_adc_main_bat_props[] = {
+	POWER_SUPPLY_PROP_STATUS,
+	POWER_SUPPLY_PROP_CHARGE_FULL_DESIGN,
+	POWER_SUPPLY_PROP_CHARGE_EMPTY_DESIGN,
+	POWER_SUPPLY_PROP_CHARGE_NOW,
+	POWER_SUPPLY_PROP_VOLTAGE_NOW,
+	POWER_SUPPLY_PROP_CURRENT_NOW,
+};
+
+static int calc_full_volt(int volt_val, int cur_val, int impedance)
+{
+	return volt_val + cur_val * impedance / 1000;
+}
+
+static int s3c_adc_bat_get_property(struct power_supply *psy,
+				    enum power_supply_property psp,
+				    union power_supply_propval *val)
+{
+	struct s3c_adc_bat *bat = container_of(psy, struct s3c_adc_bat, psy);
+
+	int new_level;
+	int full_volt;
+	const struct s3c_adc_bat_thresh *lut = bat->pdata->lut_noac;
+	unsigned int lut_size = bat->pdata->lut_noac_cnt;
+
+	if (!bat) {
+		dev_err(psy->dev, "no battery infos ?!\n");
+		return -EINVAL;
+	}
+
+	if (bat->volt_value < 0 || bat->cur_value < 0 ||
+		jiffies_to_msecs(jiffies - bat->timestamp) >
+			BAT_POLL_INTERVAL) {
+		bat->volt_value = s3c_adc_read(bat->client,
+			bat->pdata->volt_channel) * bat->pdata->volt_mult;
+		bat->cur_value = s3c_adc_read(bat->client,
+			bat->pdata->current_channel) * bat->pdata->current_mult;
+		bat->timestamp = jiffies;
+	}
+
+	if (bat->cable_plugged &&
+		((bat->pdata->gpio_charge_finished < 0) ||
+		!gpio_get_value(bat->pdata->gpio_charge_finished))) {
+		lut = bat->pdata->lut_acin;
+		lut_size = bat->pdata->lut_acin_cnt;
+	}
+
+	new_level = 100000;
+	full_volt = calc_full_volt((bat->volt_value / 1000),
+		(bat->cur_value / 1000), bat->pdata->internal_impedance);
+
+	if (full_volt < calc_full_volt(lut->volt, lut->cur,
+		bat->pdata->internal_impedance)) {
+		lut_size--;
+		while (lut_size--) {
+			int lut_volt1;
+			int lut_volt2;
+
+			lut_volt1 = calc_full_volt(lut[0].volt, lut[0].cur,
+				bat->pdata->internal_impedance);
+			lut_volt2 = calc_full_volt(lut[1].volt, lut[1].cur,
+				bat->pdata->internal_impedance);
+			if (full_volt < lut_volt1 && full_volt >= lut_volt2) {
+				new_level = (lut[1].level +
+					(lut[0].level - lut[1].level) *
+					(full_volt - lut_volt2) /
+					(lut_volt1 - lut_volt2)) * 1000;
+				break;
+			}
+			new_level = lut[1].level * 1000;
+			lut++;
+		}
+	}
+
+	bat->level = new_level;
+
+	switch (psp) {
+	case POWER_SUPPLY_PROP_STATUS:
+		if (bat->pdata->gpio_charge_finished < 0)
+			val->intval = bat->level == 100000 ?
+				POWER_SUPPLY_STATUS_FULL : bat->status;
+		else
+			val->intval = bat->status;
+		return 0;
+	case POWER_SUPPLY_PROP_CHARGE_FULL_DESIGN:
+		val->intval = 100000;
+		return 0;
+	case POWER_SUPPLY_PROP_CHARGE_EMPTY_DESIGN:
+		val->intval = 0;
+		return 0;
+	case POWER_SUPPLY_PROP_CHARGE_NOW:
+		val->intval = bat->level;
+		return 0;
+	case POWER_SUPPLY_PROP_VOLTAGE_NOW:
+		val->intval = bat->volt_value;
+		return 0;
+	case POWER_SUPPLY_PROP_CURRENT_NOW:
+		val->intval = bat->cur_value;
+		return 0;
+	default:
+		return -EINVAL;
+	}
+}
+
+static struct s3c_adc_bat main_bat = {
+	.psy = {
+		.name			= "main-battery",
+		.type			= POWER_SUPPLY_TYPE_BATTERY,
+		.properties		= s3c_adc_main_bat_props,
+		.num_properties		= ARRAY_SIZE(s3c_adc_main_bat_props),
+		.get_property		= s3c_adc_bat_get_property,
+		.external_power_changed = s3c_adc_bat_ext_power_changed,
+		.use_for_apm		= 1,
+	},
+};
+
+static void s3c_adc_bat_work(struct work_struct *work)
+{
+	struct s3c_adc_bat *bat = &main_bat;
+	int is_charged;
+	int is_plugged;
+	static int was_plugged;
+
+	is_plugged = power_supply_am_i_supplied(&bat->psy);
+	bat->cable_plugged = is_plugged;
+	if (is_plugged != was_plugged) {
+		was_plugged = is_plugged;
+		if (is_plugged) {
+			if (bat->pdata->enable_charger)
+				bat->pdata->enable_charger();
+			bat->status = POWER_SUPPLY_STATUS_CHARGING;
+		} else {
+			if (bat->pdata->disable_charger)
+				bat->pdata->disable_charger();
+			bat->status = POWER_SUPPLY_STATUS_DISCHARGING;
+		}
+	} else {
+		if ((bat->pdata->gpio_charge_finished >= 0) && is_plugged) {
+			is_charged = gpio_get_value(
+				main_bat.pdata->gpio_charge_finished);
+			if (is_charged) {
+				if (bat->pdata->disable_charger)
+					bat->pdata->disable_charger();
+				bat->status = POWER_SUPPLY_STATUS_FULL;
+			} else {
+				if (bat->pdata->enable_charger)
+					bat->pdata->enable_charger();
+				bat->status = POWER_SUPPLY_STATUS_CHARGING;
+			}
+		}
+	}
+
+	power_supply_changed(&bat->psy);
+}
+
+static irqreturn_t s3c_adc_bat_charged(int irq, void *dev_id)
+{
+	schedule_delayed_work(&bat_work,
+		msecs_to_jiffies(JITTER_DELAY));
+	return IRQ_HANDLED;
+}
+
+static int __init s3c_adc_bat_probe(struct platform_device *pdev)
+{
+	struct s3c_adc_client	*client;
+	struct s3c_adc_bat_pdata *pdata = pdev->dev.platform_data;
+	int ret;
+
+	client = s3c_adc_register(pdev, NULL, NULL, 0);
+	if (IS_ERR(client)) {
+		dev_err(&pdev->dev, "cannot register adc\n");
+		return PTR_ERR(client);
+	}
+
+	platform_set_drvdata(pdev, client);
+
+	main_bat.client = client;
+	main_bat.pdata = pdata;
+	main_bat.volt_value = -1;
+	main_bat.cur_value = -1;
+	main_bat.cable_plugged = 0;
+	main_bat.status = POWER_SUPPLY_STATUS_DISCHARGING;
+
+	ret = power_supply_register(&pdev->dev, &main_bat.psy);
+	if (ret)
+		goto err_reg_main;
+	if (pdata->backup_volt_mult) {
+		backup_bat.client = client;
+		backup_bat.pdata = pdev->dev.platform_data;
+		backup_bat.volt_value = -1;
+		ret = power_supply_register(&pdev->dev, &backup_bat.psy);
+		if (ret)
+			goto err_reg_backup;
+	}
+
+	INIT_DELAYED_WORK(&bat_work, s3c_adc_bat_work);
+
+	if (pdata->gpio_charge_finished >= 0) {
+		ret = gpio_request(pdata->gpio_charge_finished, "charged");
+		if (ret)
+			goto err_gpio;
+
+		ret = request_irq(gpio_to_irq(pdata->gpio_charge_finished),
+				s3c_adc_bat_charged,
+				IRQF_TRIGGER_RISING | IRQF_TRIGGER_FALLING,
+				"battery charged", NULL);
+		if (ret)
+			goto err_irq;
+	}
+
+	if (pdata->init) {
+		ret = pdata->init();
+		if (ret)
+			goto err_platform;
+	}
+
+	dev_info(&pdev->dev, "successfully loaded\n");
+	device_init_wakeup(&pdev->dev, 1);
+
+	/* Schedule timer to check current status */
+	schedule_delayed_work(&bat_work,
+		msecs_to_jiffies(JITTER_DELAY));
+
+	return 0;
+
+err_platform:
+	if (pdata->gpio_charge_finished >= 0)
+		free_irq(gpio_to_irq(pdata->gpio_charge_finished), NULL);
+err_irq:
+	if (pdata->gpio_charge_finished >= 0)
+		gpio_free(pdata->gpio_charge_finished);
+err_gpio:
+	if (pdata->backup_volt_mult)
+		power_supply_unregister(&backup_bat.psy);
+err_reg_backup:
+	power_supply_unregister(&main_bat.psy);
+err_reg_main:
+	return ret;
+}
+
+static int s3c_adc_bat_remove(struct platform_device *pdev)
+{
+	struct s3c_adc_client *client = platform_get_drvdata(pdev);
+	struct s3c_adc_bat_pdata *pdata = pdev->dev.platform_data;
+
+	power_supply_unregister(&main_bat.psy);
+	if (pdata->backup_volt_mult)
+		power_supply_unregister(&backup_bat.psy);
+
+	s3c_adc_release(client);
+
+	if (pdata->gpio_charge_finished >= 0) {
+		free_irq(gpio_to_irq(pdata->gpio_charge_finished), NULL);
+		gpio_free(pdata->gpio_charge_finished);
+	}
+
+	cancel_delayed_work(&bat_work);
+
+	if (pdata->exit)
+		pdata->exit();
+
+	return 0;
+}
+
+#ifdef CONFIG_PM
+static int s3c_adc_bat_suspend(struct platform_device *pdev,
+	pm_message_t state)
+{
+	struct s3c_adc_bat_pdata *pdata = pdev->dev.platform_data;
+
+	if (pdata->gpio_charge_finished >= 0) {
+		if (device_may_wakeup(&pdev->dev))
+			enable_irq_wake(
+				gpio_to_irq(pdata->gpio_charge_finished));
+		else {
+			disable_irq(gpio_to_irq(pdata->gpio_charge_finished));
+			main_bat.pdata->disable_charger();
+		}
+	}
+
+	return 0;
+}
+
+static int s3c_adc_bat_resume(struct platform_device *pdev)
+{
+	struct s3c_adc_bat_pdata *pdata = pdev->dev.platform_data;
+
+	if (pdata->gpio_charge_finished >= 0) {
+		if (device_may_wakeup(&pdev->dev))
+			disable_irq_wake(
+				gpio_to_irq(pdata->gpio_charge_finished));
+		else
+			enable_irq(gpio_to_irq(pdata->gpio_charge_finished));
+	}
+
+	/* Schedule timer to check current status */
+	schedule_delayed_work(&bat_work,
+		msecs_to_jiffies(JITTER_DELAY));
+
+	return 0;
+}
+#else
+#define s3c_adc_battery_suspend NULL
+#define s3c_adc_battery_resume NULL
+#endif
+
+static struct platform_driver s3c_adc_bat_driver = {
+	.driver		= {
+		.name	= "s3c-adc-battery",
+	},
+	.probe		= s3c_adc_bat_probe,
+	.remove		= s3c_adc_bat_remove,
+	.suspend	= s3c_adc_bat_suspend,
+	.resume		= s3c_adc_bat_resume,
+};
+
+static int __init s3c_adc_bat_init(void)
+{
+	return platform_driver_register(&s3c_adc_bat_driver);
+}
+module_init(s3c_adc_bat_init);
+
+static void __exit s3c_adc_bat_exit(void)
+{
+	platform_driver_unregister(&s3c_adc_bat_driver);
+}
+module_exit(s3c_adc_bat_exit);
+
+MODULE_AUTHOR("Vasily Khoruzhick <anarsoul@gmail.com>");
+MODULE_DESCRIPTION("iPAQ H1930/H1940/RX1950 battery controler driver");
+MODULE_LICENSE("GPL");
diff --git a/include/linux/s3c_adc_battery.h b/include/linux/s3c_adc_battery.h
new file mode 100644
index 0000000..dbce22f
--- /dev/null
+++ b/include/linux/s3c_adc_battery.h
@@ -0,0 +1,36 @@
+#ifndef _S3C_ADC_BATTERY_H
+#define _S3C_ADC_BATTERY_H
+
+struct s3c_adc_bat_thresh {
+	int volt; /* mV */
+	int cur; /* mA */
+	int level; /* percent */
+};
+
+struct s3c_adc_bat_pdata {
+	int (*init)(void);
+	void (*exit)(void);
+	void (*enable_charger)(void);
+	void (*disable_charger)(void);
+
+	int gpio_charge_finished;
+
+	const struct s3c_adc_bat_thresh *lut_noac;
+	unsigned int lut_noac_cnt;
+	const struct s3c_adc_bat_thresh *lut_acin;
+	unsigned int lut_acin_cnt;
+
+	const unsigned int volt_channel;
+	const unsigned int current_channel;
+	const unsigned int backup_volt_channel;
+
+	const unsigned int volt_mult;
+	const unsigned int current_mult;
+	const unsigned int backup_volt_mult;
+	const unsigned int internal_impedance;
+
+	const unsigned int backup_volt_max;
+	const unsigned int backup_volt_min;
+};
+
+#endif