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path: root/drivers/power/wm97xx_battery.c
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Diffstat (limited to 'drivers/power/wm97xx_battery.c')
-rw-r--r--drivers/power/wm97xx_battery.c272
1 files changed, 272 insertions, 0 deletions
diff --git a/drivers/power/wm97xx_battery.c b/drivers/power/wm97xx_battery.c
new file mode 100644
index 0000000..8bde921
--- /dev/null
+++ b/drivers/power/wm97xx_battery.c
@@ -0,0 +1,272 @@
+/*
+ * linux/drivers/power/wm97xx_battery.c
+ *
+ * Battery measurement code for WM97xx
+ *
+ * based on tosa_battery.c
+ *
+ * Copyright (C) 2008 Marek Vasut <marek.vasut@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/wm97xx.h>
+#include <linux/spinlock.h>
+#include <linux/interrupt.h>
+#include <linux/gpio.h>
+#include <linux/wm97xx_batt.h>
+
+static DEFINE_MUTEX(bat_lock);
+static struct work_struct bat_work;
+struct mutex work_lock;
+static int bat_status = POWER_SUPPLY_STATUS_UNKNOWN;
+static struct wm97xx_batt_info *pdata;
+static enum power_supply_property *prop;
+
+static unsigned long wm97xx_read_bat(struct power_supply *bat_ps)
+{
+ return wm97xx_read_aux_adc(bat_ps->dev->parent->driver_data,
+ pdata->batt_aux) * pdata->batt_mult /
+ pdata->batt_div;
+}
+
+static unsigned long wm97xx_read_temp(struct power_supply *bat_ps)
+{
+ return wm97xx_read_aux_adc(bat_ps->dev->parent->driver_data,
+ pdata->temp_aux) * pdata->temp_mult /
+ pdata->temp_div;
+}
+
+static int wm97xx_bat_get_property(struct power_supply *bat_ps,
+ enum power_supply_property psp,
+ union power_supply_propval *val)
+{
+ switch (psp) {
+ case POWER_SUPPLY_PROP_STATUS:
+ val->intval = bat_status;
+ break;
+ case POWER_SUPPLY_PROP_TECHNOLOGY:
+ val->intval = pdata->batt_tech;
+ break;
+ case POWER_SUPPLY_PROP_VOLTAGE_NOW:
+ if (pdata->batt_aux >= 0)
+ val->intval = wm97xx_read_bat(bat_ps);
+ else
+ return -EINVAL;
+ break;
+ case POWER_SUPPLY_PROP_TEMP:
+ if (pdata->temp_aux >= 0)
+ val->intval = wm97xx_read_temp(bat_ps);
+ else
+ return -EINVAL;
+ break;
+ case POWER_SUPPLY_PROP_VOLTAGE_MAX:
+ if (pdata->max_voltage >= 0)
+ val->intval = pdata->max_voltage;
+ else
+ return -EINVAL;
+ break;
+ case POWER_SUPPLY_PROP_VOLTAGE_MIN:
+ if (pdata->min_voltage >= 0)
+ val->intval = pdata->min_voltage;
+ else
+ return -EINVAL;
+ break;
+ case POWER_SUPPLY_PROP_PRESENT:
+ val->intval = 1;
+ break;
+ default:
+ return -EINVAL;
+ }
+ return 0;
+}
+
+static void wm97xx_bat_external_power_changed(struct power_supply *bat_ps)
+{
+ schedule_work(&bat_work);
+}
+
+static void wm97xx_bat_update(struct power_supply *bat_ps)
+{
+ int old_status = bat_status;
+
+ mutex_lock(&work_lock);
+
+ bat_status = (pdata->charge_gpio >= 0) ?
+ (gpio_get_value(pdata->charge_gpio) ?
+ POWER_SUPPLY_STATUS_DISCHARGING :
+ POWER_SUPPLY_STATUS_CHARGING) :
+ POWER_SUPPLY_STATUS_UNKNOWN;
+
+ if (old_status != bat_status) {
+ pr_debug("%s: %i -> %i\n", bat_ps->name, old_status,
+ bat_status);
+ power_supply_changed(bat_ps);
+ }
+
+ mutex_unlock(&work_lock);
+}
+
+static struct power_supply bat_ps = {
+ .type = POWER_SUPPLY_TYPE_BATTERY,
+ .get_property = wm97xx_bat_get_property,
+ .external_power_changed = wm97xx_bat_external_power_changed,
+ .use_for_apm = 1,
+};
+
+static void wm97xx_bat_work(struct work_struct *work)
+{
+ wm97xx_bat_update(&bat_ps);
+}
+
+#ifdef CONFIG_PM
+static int wm97xx_bat_suspend(struct platform_device *dev, pm_message_t state)
+{
+ flush_scheduled_work();
+ return 0;
+}
+
+static int wm97xx_bat_resume(struct platform_device *dev)
+{
+ schedule_work(&bat_work);
+ return 0;
+}
+#else
+#define wm97xx_bat_suspend NULL
+#define wm97xx_bat_resume NULL
+#endif
+
+static int __devinit wm97xx_bat_probe(struct platform_device *dev)
+{
+ int ret = 0;
+ int props = 1; /* POWER_SUPPLY_PROP_PRESENT */
+ int i = 0;
+
+ if (dev->id != -1)
+ return -EINVAL;
+
+ mutex_init(&work_lock);
+
+ if (!pdata) {
+ dev_err(&dev->dev, "Please use wm97xx_bat_set_pdata\n");
+ return -EINVAL;
+ }
+
+ if (pdata->charge_gpio >= 0 && gpio_is_valid(pdata->charge_gpio)) {
+ ret = gpio_request(pdata->charge_gpio, "BATT CHRG");
+ if (ret)
+ goto err;
+ ret = gpio_direction_input(pdata->charge_gpio);
+ if (ret)
+ goto err2;
+ props++; /* POWER_SUPPLY_PROP_STATUS */
+ }
+
+ if (pdata->batt_tech >= 0)
+ props++; /* POWER_SUPPLY_PROP_TECHNOLOGY */
+ if (pdata->temp_aux >= 0)
+ props++; /* POWER_SUPPLY_PROP_TEMP */
+ if (pdata->batt_aux >= 0)
+ props++; /* POWER_SUPPLY_PROP_VOLTAGE_NOW */
+ if (pdata->max_voltage >= 0)
+ props++; /* POWER_SUPPLY_PROP_VOLTAGE_MAX */
+ if (pdata->min_voltage >= 0)
+ props++; /* POWER_SUPPLY_PROP_VOLTAGE_MIN */
+
+ prop = kzalloc(props * sizeof(*prop), GFP_KERNEL);
+ if (!prop)
+ goto err2;
+
+ prop[i++] = POWER_SUPPLY_PROP_PRESENT;
+ if (pdata->charge_gpio >= 0)
+ prop[i++] = POWER_SUPPLY_PROP_STATUS;
+ if (pdata->batt_tech >= 0)
+ prop[i++] = POWER_SUPPLY_PROP_TECHNOLOGY;
+ if (pdata->temp_aux >= 0)
+ prop[i++] = POWER_SUPPLY_PROP_TEMP;
+ if (pdata->batt_aux >= 0)
+ prop[i++] = POWER_SUPPLY_PROP_VOLTAGE_NOW;
+ if (pdata->max_voltage >= 0)
+ prop[i++] = POWER_SUPPLY_PROP_VOLTAGE_MAX;
+ if (pdata->min_voltage >= 0)
+ prop[i++] = POWER_SUPPLY_PROP_VOLTAGE_MIN;
+
+ INIT_WORK(&bat_work, wm97xx_bat_work);
+
+ if (!pdata->batt_name) {
+ dev_info(&dev->dev, "Please consider setting proper battery "
+ "name in platform definition file, falling "
+ "back to name \"wm97xx-batt\"\n");
+ bat_ps.name = "wm97xx-batt";
+ } else
+ bat_ps.name = pdata->batt_name;
+
+ bat_ps.properties = prop;
+ bat_ps.num_properties = props;
+
+ ret = power_supply_register(&dev->dev, &bat_ps);
+ if (!ret)
+ schedule_work(&bat_work);
+ else
+ goto err3;
+
+ return 0;
+err3:
+ kfree(prop);
+err2:
+ gpio_free(pdata->charge_gpio);
+err:
+ return ret;
+}
+
+static int __devexit wm97xx_bat_remove(struct platform_device *dev)
+{
+ if (pdata && pdata->charge_gpio && pdata->charge_gpio >= 0)
+ gpio_free(pdata->charge_gpio);
+ flush_scheduled_work();
+ power_supply_unregister(&bat_ps);
+ kfree(prop);
+ return 0;
+}
+
+static struct platform_driver wm97xx_bat_driver = {
+ .driver = {
+ .name = "wm97xx-battery",
+ .owner = THIS_MODULE,
+ },
+ .probe = wm97xx_bat_probe,
+ .remove = __devexit_p(wm97xx_bat_remove),
+ .suspend = wm97xx_bat_suspend,
+ .resume = wm97xx_bat_resume,
+};
+
+static int __init wm97xx_bat_init(void)
+{
+ return platform_driver_register(&wm97xx_bat_driver);
+}
+
+static void __exit wm97xx_bat_exit(void)
+{
+ platform_driver_unregister(&wm97xx_bat_driver);
+}
+
+void __init wm97xx_bat_set_pdata(struct wm97xx_batt_info *data)
+{
+ pdata = data;
+}
+EXPORT_SYMBOL_GPL(wm97xx_bat_set_pdata);
+
+module_init(wm97xx_bat_init);
+module_exit(wm97xx_bat_exit);
+
+MODULE_LICENSE("GPL");
+MODULE_AUTHOR("Marek Vasut <marek.vasut@gmail.com>");
+MODULE_DESCRIPTION("WM97xx battery driver");
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