2 * Battery measurement code for Zipit Z2
4 * Copyright (C) 2009 Peter Edwards <sweetlilmre@gmail.com>
6 * This program is free software; you can redistribute it and/or modify
7 * it under the terms of the GNU General Public License version 2 as
8 * published by the Free Software Foundation.
12 #include <linux/init.h>
13 #include <linux/kernel.h>
14 #include <linux/module.h>
15 #include <linux/platform_device.h>
16 #include <linux/power_supply.h>
17 #include <linux/i2c.h>
18 #include <linux/spinlock.h>
19 #include <linux/interrupt.h>
20 #include <linux/gpio.h>
21 #include <linux/interrupt.h>
22 #include <linux/irq.h>
24 #include <asm/mach/irq.h>
25 #include <linux/z2_battery.h>
27 #define Z2_DEFAULT_NAME "Z2"
30 struct z2_battery_info *info;
32 struct i2c_client *client;
33 struct power_supply batt_ps;
34 struct mutex work_lock;
35 struct work_struct bat_work;
38 static unsigned long z2_read_bat(struct z2_charger *charger)
41 data = i2c_smbus_read_byte_data(charger->client,
42 charger->info->batt_I2C_reg);
46 return data * charger->info->batt_mult / charger->info->batt_div;
49 static int z2_batt_get_property(struct power_supply *batt_ps,
50 enum power_supply_property psp,
51 union power_supply_propval *val)
53 struct z2_charger *charger = container_of(batt_ps, struct z2_charger,
55 struct z2_battery_info *info = charger->info;
58 case POWER_SUPPLY_PROP_STATUS:
59 val->intval = charger->bat_status;
61 case POWER_SUPPLY_PROP_TECHNOLOGY:
62 val->intval = info->batt_tech;
64 case POWER_SUPPLY_PROP_VOLTAGE_NOW:
65 if (info->batt_I2C_reg >= 0)
66 val->intval = z2_read_bat(charger);
70 case POWER_SUPPLY_PROP_VOLTAGE_MAX:
71 if (info->max_voltage >= 0)
72 val->intval = info->max_voltage;
76 case POWER_SUPPLY_PROP_VOLTAGE_MIN:
77 if (info->min_voltage >= 0)
78 val->intval = info->min_voltage;
82 case POWER_SUPPLY_PROP_PRESENT:
92 static void z2_batt_ext_power_changed(struct power_supply *batt_ps)
94 struct z2_charger *charger = container_of(batt_ps, struct z2_charger,
96 schedule_work(&charger->bat_work);
99 static void z2_batt_update(struct z2_charger *charger)
101 int old_status = charger->bat_status;
102 struct z2_battery_info *info;
104 info = charger->info;
106 mutex_lock(&charger->work_lock);
108 charger->bat_status = (info->charge_gpio >= 0) ?
109 (gpio_get_value(info->charge_gpio) ?
110 POWER_SUPPLY_STATUS_CHARGING :
111 POWER_SUPPLY_STATUS_DISCHARGING) :
112 POWER_SUPPLY_STATUS_UNKNOWN;
114 if (old_status != charger->bat_status) {
115 pr_debug("%s: %i -> %i\n", charger->batt_ps.name, old_status,
116 charger->bat_status);
117 power_supply_changed(&charger->batt_ps);
120 mutex_unlock(&charger->work_lock);
123 static void z2_batt_work(struct work_struct *work)
125 struct z2_charger *charger;
126 charger = container_of(work, struct z2_charger, bat_work);
127 z2_batt_update(charger);
130 static irqreturn_t z2_charge_switch_irq(int irq, void *devid)
132 struct z2_charger *charger = devid;
133 schedule_work(&charger->bat_work);
137 static int z2_batt_ps_init(struct z2_charger *charger, int props)
140 enum power_supply_property *prop;
141 struct z2_battery_info *info = charger->info;
143 if (info->batt_tech >= 0)
144 props++; /* POWER_SUPPLY_PROP_TECHNOLOGY */
145 if (info->batt_I2C_reg >= 0)
146 props++; /* POWER_SUPPLY_PROP_VOLTAGE_NOW */
147 if (info->max_voltage >= 0)
148 props++; /* POWER_SUPPLY_PROP_VOLTAGE_MAX */
149 if (info->min_voltage >= 0)
150 props++; /* POWER_SUPPLY_PROP_VOLTAGE_MIN */
152 prop = kzalloc(props * sizeof(*prop), GFP_KERNEL);
156 prop[i++] = POWER_SUPPLY_PROP_PRESENT;
157 if (info->charge_gpio >= 0)
158 prop[i++] = POWER_SUPPLY_PROP_STATUS;
159 if (info->batt_tech >= 0)
160 prop[i++] = POWER_SUPPLY_PROP_TECHNOLOGY;
161 if (info->batt_I2C_reg >= 0)
162 prop[i++] = POWER_SUPPLY_PROP_VOLTAGE_NOW;
163 if (info->max_voltage >= 0)
164 prop[i++] = POWER_SUPPLY_PROP_VOLTAGE_MAX;
165 if (info->min_voltage >= 0)
166 prop[i++] = POWER_SUPPLY_PROP_VOLTAGE_MIN;
168 if (!info->batt_name) {
169 dev_info(&charger->client->dev,
170 "Please consider setting proper battery "
171 "name in platform definition file, falling "
172 "back to name \" Z2_DEFAULT_NAME \"\n");
173 charger->batt_ps.name = Z2_DEFAULT_NAME;
175 charger->batt_ps.name = info->batt_name;
177 charger->batt_ps.properties = prop;
178 charger->batt_ps.num_properties = props;
179 charger->batt_ps.type = POWER_SUPPLY_TYPE_BATTERY;
180 charger->batt_ps.get_property = z2_batt_get_property;
181 charger->batt_ps.external_power_changed = z2_batt_ext_power_changed;
182 charger->batt_ps.use_for_apm = 1;
187 static int __devinit z2_batt_probe(struct i2c_client *client,
188 const struct i2c_device_id *id)
191 int props = 1; /* POWER_SUPPLY_PROP_PRESENT */
192 struct z2_charger *charger;
193 struct z2_battery_info *info = client->dev.platform_data;
196 dev_err(&client->dev,
197 "Please set platform device platform_data"
198 " to a valid z2_battery_info pointer!\n");
202 charger = kzalloc(sizeof(*charger), GFP_KERNEL);
206 charger->bat_status = POWER_SUPPLY_STATUS_UNKNOWN;
207 charger->info = info;
208 charger->client = client;
209 i2c_set_clientdata(client, charger);
211 mutex_init(&charger->work_lock);
213 if (info->charge_gpio >= 0 && gpio_is_valid(info->charge_gpio)) {
214 ret = gpio_request(info->charge_gpio, "BATT CHRG");
218 ret = gpio_direction_input(info->charge_gpio);
222 set_irq_type(gpio_to_irq(info->charge_gpio),
224 ret = request_irq(gpio_to_irq(info->charge_gpio),
225 z2_charge_switch_irq, IRQF_DISABLED,
226 "AC Detect", charger);
231 ret = z2_batt_ps_init(charger, props);
235 INIT_WORK(&charger->bat_work, z2_batt_work);
237 ret = power_supply_register(&client->dev, &charger->batt_ps);
241 schedule_work(&charger->bat_work);
246 kfree(charger->batt_ps.properties);
248 if (info->charge_gpio >= 0 && gpio_is_valid(info->charge_gpio))
249 free_irq(gpio_to_irq(info->charge_gpio), charger);
251 if (info->charge_gpio >= 0 && gpio_is_valid(info->charge_gpio))
252 gpio_free(info->charge_gpio);
258 static int __devexit z2_batt_remove(struct i2c_client *client)
260 struct z2_charger *charger = i2c_get_clientdata(client);
261 struct z2_battery_info *info = charger->info;
263 flush_scheduled_work();
264 power_supply_unregister(&charger->batt_ps);
266 kfree(charger->batt_ps.properties);
267 if (info->charge_gpio >= 0 && gpio_is_valid(info->charge_gpio)) {
268 free_irq(gpio_to_irq(info->charge_gpio), charger);
269 gpio_free(info->charge_gpio);
278 static int z2_batt_suspend(struct i2c_client *client, pm_message_t state)
280 flush_scheduled_work();
284 static int z2_batt_resume(struct i2c_client *client)
286 struct z2_charger *charger = i2c_get_clientdata(client);
288 schedule_work(&charger->bat_work);
292 #define z2_batt_suspend NULL
293 #define z2_batt_resume NULL
296 static const struct i2c_device_id z2_batt_id[] = {
301 static struct i2c_driver z2_batt_driver = {
303 .name = "z2-battery",
304 .owner = THIS_MODULE,
306 .probe = z2_batt_probe,
307 .remove = z2_batt_remove,
308 .suspend = z2_batt_suspend,
309 .resume = z2_batt_resume,
310 .id_table = z2_batt_id,
313 static int __init z2_batt_init(void)
315 return i2c_add_driver(&z2_batt_driver);
318 static void __exit z2_batt_exit(void)
320 i2c_del_driver(&z2_batt_driver);
323 module_init(z2_batt_init);
324 module_exit(z2_batt_exit);
326 MODULE_LICENSE("GPL");
327 MODULE_AUTHOR("Peter Edwards <sweetlilmre@gmail.com>");
328 MODULE_DESCRIPTION("Zipit Z2 battery driver");