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path: root/drivers/power/z2_battery.c
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Diffstat (limited to 'drivers/power/z2_battery.c')
-rw-r--r--drivers/power/z2_battery.c328
1 files changed, 328 insertions, 0 deletions
diff --git a/drivers/power/z2_battery.c b/drivers/power/z2_battery.c
new file mode 100644
index 0000000..9cca465
--- /dev/null
+++ b/drivers/power/z2_battery.c
@@ -0,0 +1,328 @@
+/*
+ * Battery measurement code for Zipit Z2
+ *
+ * Copyright (C) 2009 Peter Edwards <sweetlilmre@gmail.com>
+ *
+ * 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/init.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/platform_device.h>
+#include <linux/power_supply.h>
+#include <linux/i2c.h>
+#include <linux/spinlock.h>
+#include <linux/interrupt.h>
+#include <linux/gpio.h>
+#include <linux/interrupt.h>
+#include <linux/irq.h>
+#include <asm/irq.h>
+#include <asm/mach/irq.h>
+#include <linux/z2_battery.h>
+
+#define Z2_DEFAULT_NAME "Z2"
+
+struct z2_charger {
+ struct z2_battery_info *info;
+ int bat_status;
+ struct i2c_client *client;
+ struct power_supply batt_ps;
+ struct mutex work_lock;
+ struct work_struct bat_work;
+};
+
+static unsigned long z2_read_bat(struct z2_charger *charger)
+{
+ int data;
+ data = i2c_smbus_read_byte_data(charger->client,
+ charger->info->batt_I2C_reg);
+ if (data < 0)
+ return 0;
+
+ return data * charger->info->batt_mult / charger->info->batt_div;
+}
+
+static int z2_batt_get_property(struct power_supply *batt_ps,
+ enum power_supply_property psp,
+ union power_supply_propval *val)
+{
+ struct z2_charger *charger = container_of(batt_ps, struct z2_charger,
+ batt_ps);
+ struct z2_battery_info *info = charger->info;
+
+ switch (psp) {
+ case POWER_SUPPLY_PROP_STATUS:
+ val->intval = charger->bat_status;
+ break;
+ case POWER_SUPPLY_PROP_TECHNOLOGY:
+ val->intval = info->batt_tech;
+ break;
+ case POWER_SUPPLY_PROP_VOLTAGE_NOW:
+ if (info->batt_I2C_reg >= 0)
+ val->intval = z2_read_bat(charger);
+ else
+ return -EINVAL;
+ break;
+ case POWER_SUPPLY_PROP_VOLTAGE_MAX:
+ if (info->max_voltage >= 0)
+ val->intval = info->max_voltage;
+ else
+ return -EINVAL;
+ break;
+ case POWER_SUPPLY_PROP_VOLTAGE_MIN:
+ if (info->min_voltage >= 0)
+ val->intval = info->min_voltage;
+ else
+ return -EINVAL;
+ break;
+ case POWER_SUPPLY_PROP_PRESENT:
+ val->intval = 1;
+ break;
+ default:
+ return -EINVAL;
+ }
+
+ return 0;
+}
+
+static void z2_batt_ext_power_changed(struct power_supply *batt_ps)
+{
+ struct z2_charger *charger = container_of(batt_ps, struct z2_charger,
+ batt_ps);
+ schedule_work(&charger->bat_work);
+}
+
+static void z2_batt_update(struct z2_charger *charger)
+{
+ int old_status = charger->bat_status;
+ struct z2_battery_info *info;
+
+ info = charger->info;
+
+ mutex_lock(&charger->work_lock);
+
+ charger->bat_status = (info->charge_gpio >= 0) ?
+ (gpio_get_value(info->charge_gpio) ?
+ POWER_SUPPLY_STATUS_CHARGING :
+ POWER_SUPPLY_STATUS_DISCHARGING) :
+ POWER_SUPPLY_STATUS_UNKNOWN;
+
+ if (old_status != charger->bat_status) {
+ pr_debug("%s: %i -> %i\n", charger->batt_ps.name, old_status,
+ charger->bat_status);
+ power_supply_changed(&charger->batt_ps);
+ }
+
+ mutex_unlock(&charger->work_lock);
+}
+
+static void z2_batt_work(struct work_struct *work)
+{
+ struct z2_charger *charger;
+ charger = container_of(work, struct z2_charger, bat_work);
+ z2_batt_update(charger);
+}
+
+static irqreturn_t z2_charge_switch_irq(int irq, void *devid)
+{
+ struct z2_charger *charger = devid;
+ schedule_work(&charger->bat_work);
+ return IRQ_HANDLED;
+}
+
+static int z2_batt_ps_init(struct z2_charger *charger, int props)
+{
+ int i = 0;
+ enum power_supply_property *prop;
+ struct z2_battery_info *info = charger->info;
+
+ if (info->batt_tech >= 0)
+ props++; /* POWER_SUPPLY_PROP_TECHNOLOGY */
+ if (info->batt_I2C_reg >= 0)
+ props++; /* POWER_SUPPLY_PROP_VOLTAGE_NOW */
+ if (info->max_voltage >= 0)
+ props++; /* POWER_SUPPLY_PROP_VOLTAGE_MAX */
+ if (info->min_voltage >= 0)
+ props++; /* POWER_SUPPLY_PROP_VOLTAGE_MIN */
+
+ prop = kzalloc(props * sizeof(*prop), GFP_KERNEL);
+ if (!prop)
+ return -ENOMEM;
+
+ prop[i++] = POWER_SUPPLY_PROP_PRESENT;
+ if (info->charge_gpio >= 0)
+ prop[i++] = POWER_SUPPLY_PROP_STATUS;
+ if (info->batt_tech >= 0)
+ prop[i++] = POWER_SUPPLY_PROP_TECHNOLOGY;
+ if (info->batt_I2C_reg >= 0)
+ prop[i++] = POWER_SUPPLY_PROP_VOLTAGE_NOW;
+ if (info->max_voltage >= 0)
+ prop[i++] = POWER_SUPPLY_PROP_VOLTAGE_MAX;
+ if (info->min_voltage >= 0)
+ prop[i++] = POWER_SUPPLY_PROP_VOLTAGE_MIN;
+
+ if (!info->batt_name) {
+ dev_info(&charger->client->dev,
+ "Please consider setting proper battery "
+ "name in platform definition file, falling "
+ "back to name \" Z2_DEFAULT_NAME \"\n");
+ charger->batt_ps.name = Z2_DEFAULT_NAME;
+ } else
+ charger->batt_ps.name = info->batt_name;
+
+ charger->batt_ps.properties = prop;
+ charger->batt_ps.num_properties = props;
+ charger->batt_ps.type = POWER_SUPPLY_TYPE_BATTERY;
+ charger->batt_ps.get_property = z2_batt_get_property;
+ charger->batt_ps.external_power_changed = z2_batt_ext_power_changed;
+ charger->batt_ps.use_for_apm = 1;
+
+ return 0;
+}
+
+static int __devinit z2_batt_probe(struct i2c_client *client,
+ const struct i2c_device_id *id)
+{
+ int ret = 0;
+ int props = 1; /* POWER_SUPPLY_PROP_PRESENT */
+ struct z2_charger *charger;
+ struct z2_battery_info *info = client->dev.platform_data;
+
+ if (info == NULL) {
+ dev_err(&client->dev,
+ "Please set platform device platform_data"
+ " to a valid z2_battery_info pointer!\n");
+ return -EINVAL;
+ }
+
+ charger = kzalloc(sizeof(*charger), GFP_KERNEL);
+ if (charger == NULL)
+ return -ENOMEM;
+
+ charger->bat_status = POWER_SUPPLY_STATUS_UNKNOWN;
+ charger->info = info;
+ charger->client = client;
+ i2c_set_clientdata(client, charger);
+
+ mutex_init(&charger->work_lock);
+
+ if (info->charge_gpio >= 0 && gpio_is_valid(info->charge_gpio)) {
+ ret = gpio_request(info->charge_gpio, "BATT CHRG");
+ if (ret)
+ goto err;
+
+ ret = gpio_direction_input(info->charge_gpio);
+ if (ret)
+ goto err2;
+
+ set_irq_type(gpio_to_irq(info->charge_gpio),
+ IRQ_TYPE_EDGE_BOTH);
+ ret = request_irq(gpio_to_irq(info->charge_gpio),
+ z2_charge_switch_irq, IRQF_DISABLED,
+ "AC Detect", charger);
+ if (ret)
+ goto err3;
+ }
+
+ ret = z2_batt_ps_init(charger, props);
+ if (ret)
+ goto err3;
+
+ INIT_WORK(&charger->bat_work, z2_batt_work);
+
+ ret = power_supply_register(&client->dev, &charger->batt_ps);
+ if (ret)
+ goto err4;
+
+ schedule_work(&charger->bat_work);
+
+ return 0;
+
+err4:
+ kfree(charger->batt_ps.properties);
+err3:
+ if (info->charge_gpio >= 0 && gpio_is_valid(info->charge_gpio))
+ free_irq(gpio_to_irq(info->charge_gpio), charger);
+err2:
+ if (info->charge_gpio >= 0 && gpio_is_valid(info->charge_gpio))
+ gpio_free(info->charge_gpio);
+err:
+ kfree(charger);
+ return ret;
+}
+
+static int __devexit z2_batt_remove(struct i2c_client *client)
+{
+ struct z2_charger *charger = i2c_get_clientdata(client);
+ struct z2_battery_info *info = charger->info;
+
+ flush_scheduled_work();
+ power_supply_unregister(&charger->batt_ps);
+
+ kfree(charger->batt_ps.properties);
+ if (info->charge_gpio >= 0 && gpio_is_valid(info->charge_gpio)) {
+ free_irq(gpio_to_irq(info->charge_gpio), charger);
+ gpio_free(info->charge_gpio);
+ }
+
+ kfree(charger);
+
+ return 0;
+}
+
+#ifdef CONFIG_PM
+static int z2_batt_suspend(struct i2c_client *client, pm_message_t state)
+{
+ flush_scheduled_work();
+ return 0;
+}
+
+static int z2_batt_resume(struct i2c_client *client)
+{
+ struct z2_charger *charger = i2c_get_clientdata(client);
+
+ schedule_work(&charger->bat_work);
+ return 0;
+}
+#else
+#define z2_batt_suspend NULL
+#define z2_batt_resume NULL
+#endif
+
+static const struct i2c_device_id z2_batt_id[] = {
+ { "aer915", 0 },
+ { }
+};
+
+static struct i2c_driver z2_batt_driver = {
+ .driver = {
+ .name = "z2-battery",
+ .owner = THIS_MODULE,
+ },
+ .probe = z2_batt_probe,
+ .remove = z2_batt_remove,
+ .suspend = z2_batt_suspend,
+ .resume = z2_batt_resume,
+ .id_table = z2_batt_id,
+};
+
+static int __init z2_batt_init(void)
+{
+ return i2c_add_driver(&z2_batt_driver);
+}
+
+static void __exit z2_batt_exit(void)
+{
+ i2c_del_driver(&z2_batt_driver);
+}
+
+module_init(z2_batt_init);
+module_exit(z2_batt_exit);
+
+MODULE_LICENSE("GPL");
+MODULE_AUTHOR("Peter Edwards <sweetlilmre@gmail.com>");
+MODULE_DESCRIPTION("Zipit Z2 battery driver");
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