blob: e5ed52d719376e41c35de6c1368c8723af532f89 [file] [log] [blame]
Marek Vasute3e8d1c2010-02-28 12:47:49 +01001/*
2 * Battery measurement code for Zipit Z2
3 *
4 * Copyright (C) 2009 Peter Edwards <sweetlilmre@gmail.com>
5 *
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.
9 *
10 */
11
Marek Vasute3e8d1c2010-02-28 12:47:49 +010012#include <linux/module.h>
Marek Vasute3e8d1c2010-02-28 12:47:49 +010013#include <linux/gpio.h>
Marek Vasut56b925f2010-06-03 03:44:00 +020014#include <linux/i2c.h>
Marek Vasute3e8d1c2010-02-28 12:47:49 +010015#include <linux/interrupt.h>
16#include <linux/irq.h>
Marek Vasut56b925f2010-06-03 03:44:00 +020017#include <linux/power_supply.h>
18#include <linux/slab.h>
Marek Vasute3e8d1c2010-02-28 12:47:49 +010019#include <linux/z2_battery.h>
20
21#define Z2_DEFAULT_NAME "Z2"
22
23struct z2_charger {
24 struct z2_battery_info *info;
25 int bat_status;
26 struct i2c_client *client;
27 struct power_supply batt_ps;
28 struct mutex work_lock;
29 struct work_struct bat_work;
30};
31
32static unsigned long z2_read_bat(struct z2_charger *charger)
33{
34 int data;
35 data = i2c_smbus_read_byte_data(charger->client,
36 charger->info->batt_I2C_reg);
37 if (data < 0)
38 return 0;
39
40 return data * charger->info->batt_mult / charger->info->batt_div;
41}
42
43static int z2_batt_get_property(struct power_supply *batt_ps,
44 enum power_supply_property psp,
45 union power_supply_propval *val)
46{
47 struct z2_charger *charger = container_of(batt_ps, struct z2_charger,
48 batt_ps);
49 struct z2_battery_info *info = charger->info;
50
51 switch (psp) {
52 case POWER_SUPPLY_PROP_STATUS:
53 val->intval = charger->bat_status;
54 break;
55 case POWER_SUPPLY_PROP_TECHNOLOGY:
56 val->intval = info->batt_tech;
57 break;
58 case POWER_SUPPLY_PROP_VOLTAGE_NOW:
59 if (info->batt_I2C_reg >= 0)
60 val->intval = z2_read_bat(charger);
61 else
62 return -EINVAL;
63 break;
64 case POWER_SUPPLY_PROP_VOLTAGE_MAX:
65 if (info->max_voltage >= 0)
66 val->intval = info->max_voltage;
67 else
68 return -EINVAL;
69 break;
70 case POWER_SUPPLY_PROP_VOLTAGE_MIN:
71 if (info->min_voltage >= 0)
72 val->intval = info->min_voltage;
73 else
74 return -EINVAL;
75 break;
76 case POWER_SUPPLY_PROP_PRESENT:
77 val->intval = 1;
78 break;
79 default:
80 return -EINVAL;
81 }
82
83 return 0;
84}
85
86static void z2_batt_ext_power_changed(struct power_supply *batt_ps)
87{
88 struct z2_charger *charger = container_of(batt_ps, struct z2_charger,
89 batt_ps);
90 schedule_work(&charger->bat_work);
91}
92
93static void z2_batt_update(struct z2_charger *charger)
94{
95 int old_status = charger->bat_status;
96 struct z2_battery_info *info;
97
98 info = charger->info;
99
100 mutex_lock(&charger->work_lock);
101
102 charger->bat_status = (info->charge_gpio >= 0) ?
103 (gpio_get_value(info->charge_gpio) ?
104 POWER_SUPPLY_STATUS_CHARGING :
105 POWER_SUPPLY_STATUS_DISCHARGING) :
106 POWER_SUPPLY_STATUS_UNKNOWN;
107
108 if (old_status != charger->bat_status) {
109 pr_debug("%s: %i -> %i\n", charger->batt_ps.name, old_status,
110 charger->bat_status);
111 power_supply_changed(&charger->batt_ps);
112 }
113
114 mutex_unlock(&charger->work_lock);
115}
116
117static void z2_batt_work(struct work_struct *work)
118{
119 struct z2_charger *charger;
120 charger = container_of(work, struct z2_charger, bat_work);
121 z2_batt_update(charger);
122}
123
124static irqreturn_t z2_charge_switch_irq(int irq, void *devid)
125{
126 struct z2_charger *charger = devid;
127 schedule_work(&charger->bat_work);
128 return IRQ_HANDLED;
129}
130
131static int z2_batt_ps_init(struct z2_charger *charger, int props)
132{
133 int i = 0;
134 enum power_supply_property *prop;
135 struct z2_battery_info *info = charger->info;
136
137 if (info->batt_tech >= 0)
138 props++; /* POWER_SUPPLY_PROP_TECHNOLOGY */
139 if (info->batt_I2C_reg >= 0)
140 props++; /* POWER_SUPPLY_PROP_VOLTAGE_NOW */
141 if (info->max_voltage >= 0)
142 props++; /* POWER_SUPPLY_PROP_VOLTAGE_MAX */
143 if (info->min_voltage >= 0)
144 props++; /* POWER_SUPPLY_PROP_VOLTAGE_MIN */
145
146 prop = kzalloc(props * sizeof(*prop), GFP_KERNEL);
147 if (!prop)
148 return -ENOMEM;
149
150 prop[i++] = POWER_SUPPLY_PROP_PRESENT;
151 if (info->charge_gpio >= 0)
152 prop[i++] = POWER_SUPPLY_PROP_STATUS;
153 if (info->batt_tech >= 0)
154 prop[i++] = POWER_SUPPLY_PROP_TECHNOLOGY;
155 if (info->batt_I2C_reg >= 0)
156 prop[i++] = POWER_SUPPLY_PROP_VOLTAGE_NOW;
157 if (info->max_voltage >= 0)
158 prop[i++] = POWER_SUPPLY_PROP_VOLTAGE_MAX;
159 if (info->min_voltage >= 0)
160 prop[i++] = POWER_SUPPLY_PROP_VOLTAGE_MIN;
161
162 if (!info->batt_name) {
163 dev_info(&charger->client->dev,
164 "Please consider setting proper battery "
165 "name in platform definition file, falling "
166 "back to name \" Z2_DEFAULT_NAME \"\n");
167 charger->batt_ps.name = Z2_DEFAULT_NAME;
168 } else
169 charger->batt_ps.name = info->batt_name;
170
171 charger->batt_ps.properties = prop;
172 charger->batt_ps.num_properties = props;
173 charger->batt_ps.type = POWER_SUPPLY_TYPE_BATTERY;
174 charger->batt_ps.get_property = z2_batt_get_property;
175 charger->batt_ps.external_power_changed = z2_batt_ext_power_changed;
176 charger->batt_ps.use_for_apm = 1;
177
178 return 0;
179}
180
181static int __devinit z2_batt_probe(struct i2c_client *client,
182 const struct i2c_device_id *id)
183{
184 int ret = 0;
185 int props = 1; /* POWER_SUPPLY_PROP_PRESENT */
186 struct z2_charger *charger;
187 struct z2_battery_info *info = client->dev.platform_data;
188
189 if (info == NULL) {
190 dev_err(&client->dev,
191 "Please set platform device platform_data"
192 " to a valid z2_battery_info pointer!\n");
193 return -EINVAL;
194 }
195
196 charger = kzalloc(sizeof(*charger), GFP_KERNEL);
197 if (charger == NULL)
198 return -ENOMEM;
199
200 charger->bat_status = POWER_SUPPLY_STATUS_UNKNOWN;
201 charger->info = info;
202 charger->client = client;
203 i2c_set_clientdata(client, charger);
204
205 mutex_init(&charger->work_lock);
206
207 if (info->charge_gpio >= 0 && gpio_is_valid(info->charge_gpio)) {
208 ret = gpio_request(info->charge_gpio, "BATT CHRG");
209 if (ret)
210 goto err;
211
212 ret = gpio_direction_input(info->charge_gpio);
213 if (ret)
214 goto err2;
215
216 set_irq_type(gpio_to_irq(info->charge_gpio),
217 IRQ_TYPE_EDGE_BOTH);
218 ret = request_irq(gpio_to_irq(info->charge_gpio),
219 z2_charge_switch_irq, IRQF_DISABLED,
220 "AC Detect", charger);
221 if (ret)
222 goto err3;
223 }
224
225 ret = z2_batt_ps_init(charger, props);
226 if (ret)
227 goto err3;
228
229 INIT_WORK(&charger->bat_work, z2_batt_work);
230
231 ret = power_supply_register(&client->dev, &charger->batt_ps);
232 if (ret)
233 goto err4;
234
235 schedule_work(&charger->bat_work);
236
237 return 0;
238
239err4:
240 kfree(charger->batt_ps.properties);
241err3:
242 if (info->charge_gpio >= 0 && gpio_is_valid(info->charge_gpio))
243 free_irq(gpio_to_irq(info->charge_gpio), charger);
244err2:
245 if (info->charge_gpio >= 0 && gpio_is_valid(info->charge_gpio))
246 gpio_free(info->charge_gpio);
247err:
248 kfree(charger);
249 return ret;
250}
251
252static int __devexit z2_batt_remove(struct i2c_client *client)
253{
254 struct z2_charger *charger = i2c_get_clientdata(client);
255 struct z2_battery_info *info = charger->info;
256
Tejun Heobc51e7f2010-12-11 17:51:45 +0100257 cancel_work_sync(&charger->bat_work);
Marek Vasute3e8d1c2010-02-28 12:47:49 +0100258 power_supply_unregister(&charger->batt_ps);
259
260 kfree(charger->batt_ps.properties);
261 if (info->charge_gpio >= 0 && gpio_is_valid(info->charge_gpio)) {
262 free_irq(gpio_to_irq(info->charge_gpio), charger);
263 gpio_free(info->charge_gpio);
264 }
265
266 kfree(charger);
267
268 return 0;
269}
270
271#ifdef CONFIG_PM
272static int z2_batt_suspend(struct i2c_client *client, pm_message_t state)
273{
Tejun Heobc51e7f2010-12-11 17:51:45 +0100274 struct z2_charger *charger = i2c_get_clientdata(client);
275
276 flush_work_sync(&charger->bat_work);
Marek Vasute3e8d1c2010-02-28 12:47:49 +0100277 return 0;
278}
279
280static int z2_batt_resume(struct i2c_client *client)
281{
282 struct z2_charger *charger = i2c_get_clientdata(client);
283
284 schedule_work(&charger->bat_work);
285 return 0;
286}
287#else
288#define z2_batt_suspend NULL
289#define z2_batt_resume NULL
290#endif
291
292static const struct i2c_device_id z2_batt_id[] = {
293 { "aer915", 0 },
294 { }
295};
296
297static struct i2c_driver z2_batt_driver = {
298 .driver = {
299 .name = "z2-battery",
300 .owner = THIS_MODULE,
301 },
302 .probe = z2_batt_probe,
303 .remove = z2_batt_remove,
304 .suspend = z2_batt_suspend,
305 .resume = z2_batt_resume,
306 .id_table = z2_batt_id,
307};
308
309static int __init z2_batt_init(void)
310{
311 return i2c_add_driver(&z2_batt_driver);
312}
313
314static void __exit z2_batt_exit(void)
315{
316 i2c_del_driver(&z2_batt_driver);
317}
318
319module_init(z2_batt_init);
320module_exit(z2_batt_exit);
321
322MODULE_LICENSE("GPL");
323MODULE_AUTHOR("Peter Edwards <sweetlilmre@gmail.com>");
324MODULE_DESCRIPTION("Zipit Z2 battery driver");