diff options
Diffstat (limited to 'kernel/drivers/power/z2_battery.c')
-rw-r--r-- | kernel/drivers/power/z2_battery.c | 331 |
1 files changed, 331 insertions, 0 deletions
diff --git a/kernel/drivers/power/z2_battery.c b/kernel/drivers/power/z2_battery.c new file mode 100644 index 000000000..b201e3fac --- /dev/null +++ b/kernel/drivers/power/z2_battery.c @@ -0,0 +1,331 @@ +/* + * 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/module.h> +#include <linux/gpio.h> +#include <linux/i2c.h> +#include <linux/interrupt.h> +#include <linux/irq.h> +#include <linux/power_supply.h> +#include <linux/slab.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 power_supply_desc batt_ps_desc; + 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 = power_supply_get_drvdata(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 = power_supply_get_drvdata(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->desc->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->charge_gpio >= 0) + props++; /* POWER_SUPPLY_PROP_STATUS */ + 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_desc.name = Z2_DEFAULT_NAME; + } else + charger->batt_ps_desc.name = info->batt_name; + + charger->batt_ps_desc.properties = prop; + charger->batt_ps_desc.num_properties = props; + charger->batt_ps_desc.type = POWER_SUPPLY_TYPE_BATTERY; + charger->batt_ps_desc.get_property = z2_batt_get_property; + charger->batt_ps_desc.external_power_changed = + z2_batt_ext_power_changed; + charger->batt_ps_desc.use_for_apm = 1; + + return 0; +} + +static int 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; + struct power_supply_config psy_cfg = {}; + + 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); + psy_cfg.drv_data = 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; + + irq_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, 0, + "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); + + charger->batt_ps = power_supply_register(&client->dev, + &charger->batt_ps_desc, + &psy_cfg); + if (IS_ERR(charger->batt_ps)) { + ret = PTR_ERR(charger->batt_ps); + goto err4; + } + + schedule_work(&charger->bat_work); + + return 0; + +err4: + kfree(charger->batt_ps_desc.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 z2_batt_remove(struct i2c_client *client) +{ + struct z2_charger *charger = i2c_get_clientdata(client); + struct z2_battery_info *info = charger->info; + + cancel_work_sync(&charger->bat_work); + power_supply_unregister(charger->batt_ps); + + kfree(charger->batt_ps_desc.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 device *dev) +{ + struct i2c_client *client = to_i2c_client(dev); + struct z2_charger *charger = i2c_get_clientdata(client); + + flush_work(&charger->bat_work); + return 0; +} + +static int z2_batt_resume(struct device *dev) +{ + struct i2c_client *client = to_i2c_client(dev); + struct z2_charger *charger = i2c_get_clientdata(client); + + schedule_work(&charger->bat_work); + return 0; +} + +static const struct dev_pm_ops z2_battery_pm_ops = { + .suspend = z2_batt_suspend, + .resume = z2_batt_resume, +}; + +#define Z2_BATTERY_PM_OPS (&z2_battery_pm_ops) + +#else +#define Z2_BATTERY_PM_OPS (NULL) +#endif + +static const struct i2c_device_id z2_batt_id[] = { + { "aer915", 0 }, + { } +}; +MODULE_DEVICE_TABLE(i2c, z2_batt_id); + +static struct i2c_driver z2_batt_driver = { + .driver = { + .name = "z2-battery", + .owner = THIS_MODULE, + .pm = Z2_BATTERY_PM_OPS + }, + .probe = z2_batt_probe, + .remove = z2_batt_remove, + .id_table = z2_batt_id, +}; +module_i2c_driver(z2_batt_driver); + +MODULE_LICENSE("GPL"); +MODULE_AUTHOR("Peter Edwards <sweetlilmre@gmail.com>"); +MODULE_DESCRIPTION("Zipit Z2 battery driver"); |