IB/mlx4: Fix MTT leakage in resize CQ
[linux-2.6] / drivers / power / bq27x00_battery.c
1 /*
2  * BQ27x00 battery driver
3  *
4  * Copyright (C) 2008 Rodolfo Giometti <giometti@linux.it>
5  * Copyright (C) 2008 Eurotech S.p.A. <info@eurotech.it>
6  *
7  * Based on a previous work by Copyright (C) 2008 Texas Instruments, Inc.
8  *
9  * This package is free software; you can redistribute it and/or modify
10  * it under the terms of the GNU General Public License version 2 as
11  * published by the Free Software Foundation.
12  *
13  * THIS PACKAGE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR
14  * IMPLIED WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED
15  * WARRANTIES OF MERCHANTIBILITY AND FITNESS FOR A PARTICULAR PURPOSE.
16  *
17  */
18 #include <linux/module.h>
19 #include <linux/param.h>
20 #include <linux/jiffies.h>
21 #include <linux/workqueue.h>
22 #include <linux/delay.h>
23 #include <linux/platform_device.h>
24 #include <linux/power_supply.h>
25 #include <linux/idr.h>
26 #include <linux/i2c.h>
27 #include <asm/unaligned.h>
28
29 #define DRIVER_VERSION                  "1.0.0"
30
31 #define BQ27x00_REG_TEMP                0x06
32 #define BQ27x00_REG_VOLT                0x08
33 #define BQ27x00_REG_RSOC                0x0B /* Relative State-of-Charge */
34 #define BQ27x00_REG_AI                  0x14
35 #define BQ27x00_REG_FLAGS               0x0A
36
37 /* If the system has several batteries we need a different name for each
38  * of them...
39  */
40 static DEFINE_IDR(battery_id);
41 static DEFINE_MUTEX(battery_mutex);
42
43 struct bq27x00_device_info;
44 struct bq27x00_access_methods {
45         int (*read)(u8 reg, int *rt_value, int b_single,
46                 struct bq27x00_device_info *di);
47 };
48
49 struct bq27x00_device_info {
50         struct device           *dev;
51         int                     id;
52         int                     voltage_uV;
53         int                     current_uA;
54         int                     temp_C;
55         int                     charge_rsoc;
56         struct bq27x00_access_methods   *bus;
57         struct power_supply     bat;
58
59         struct i2c_client       *client;
60 };
61
62 static enum power_supply_property bq27x00_battery_props[] = {
63         POWER_SUPPLY_PROP_PRESENT,
64         POWER_SUPPLY_PROP_VOLTAGE_NOW,
65         POWER_SUPPLY_PROP_CURRENT_NOW,
66         POWER_SUPPLY_PROP_CAPACITY,
67         POWER_SUPPLY_PROP_TEMP,
68 };
69
70 /*
71  * Common code for BQ27x00 devices
72  */
73
74 static int bq27x00_read(u8 reg, int *rt_value, int b_single,
75                         struct bq27x00_device_info *di)
76 {
77         int ret;
78
79         ret = di->bus->read(reg, rt_value, b_single, di);
80         *rt_value = be16_to_cpu(*rt_value);
81
82         return ret;
83 }
84
85 /*
86  * Return the battery temperature in Celcius degrees
87  * Or < 0 if something fails.
88  */
89 static int bq27x00_battery_temperature(struct bq27x00_device_info *di)
90 {
91         int ret;
92         int temp = 0;
93
94         ret = bq27x00_read(BQ27x00_REG_TEMP, &temp, 0, di);
95         if (ret) {
96                 dev_err(di->dev, "error reading temperature\n");
97                 return ret;
98         }
99
100         return (temp >> 2) - 273;
101 }
102
103 /*
104  * Return the battery Voltage in milivolts
105  * Or < 0 if something fails.
106  */
107 static int bq27x00_battery_voltage(struct bq27x00_device_info *di)
108 {
109         int ret;
110         int volt = 0;
111
112         ret = bq27x00_read(BQ27x00_REG_VOLT, &volt, 0, di);
113         if (ret) {
114                 dev_err(di->dev, "error reading voltage\n");
115                 return ret;
116         }
117
118         return volt;
119 }
120
121 /*
122  * Return the battery average current
123  * Note that current can be negative signed as well
124  * Or 0 if something fails.
125  */
126 static int bq27x00_battery_current(struct bq27x00_device_info *di)
127 {
128         int ret;
129         int curr = 0;
130         int flags = 0;
131
132         ret = bq27x00_read(BQ27x00_REG_AI, &curr, 0, di);
133         if (ret) {
134                 dev_err(di->dev, "error reading current\n");
135                 return 0;
136         }
137         ret = bq27x00_read(BQ27x00_REG_FLAGS, &flags, 0, di);
138         if (ret < 0) {
139                 dev_err(di->dev, "error reading flags\n");
140                 return 0;
141         }
142         if ((flags & (1 << 7)) != 0) {
143                 dev_dbg(di->dev, "negative current!\n");
144                 return -curr;
145         }
146         return curr;
147 }
148
149 /*
150  * Return the battery Relative State-of-Charge
151  * Or < 0 if something fails.
152  */
153 static int bq27x00_battery_rsoc(struct bq27x00_device_info *di)
154 {
155         int ret;
156         int rsoc = 0;
157
158         ret = bq27x00_read(BQ27x00_REG_RSOC, &rsoc, 1, di);
159         if (ret) {
160                 dev_err(di->dev, "error reading relative State-of-Charge\n");
161                 return ret;
162         }
163
164         return rsoc >> 8;
165 }
166
167 #define to_bq27x00_device_info(x) container_of((x), \
168                                 struct bq27x00_device_info, bat);
169
170 static int bq27x00_battery_get_property(struct power_supply *psy,
171                                         enum power_supply_property psp,
172                                         union power_supply_propval *val)
173 {
174         struct bq27x00_device_info *di = to_bq27x00_device_info(psy);
175
176         switch (psp) {
177         case POWER_SUPPLY_PROP_VOLTAGE_NOW:
178         case POWER_SUPPLY_PROP_PRESENT:
179                 val->intval = bq27x00_battery_voltage(di);
180                 if (psp == POWER_SUPPLY_PROP_PRESENT)
181                         val->intval = val->intval <= 0 ? 0 : 1;
182                 break;
183         case POWER_SUPPLY_PROP_CURRENT_NOW:
184                 val->intval = bq27x00_battery_current(di);
185                 break;
186         case POWER_SUPPLY_PROP_CAPACITY:
187                 val->intval = bq27x00_battery_rsoc(di);
188                 break;
189         case POWER_SUPPLY_PROP_TEMP:
190                 val->intval = bq27x00_battery_temperature(di);
191                 break;
192         default:
193                 return -EINVAL;
194         }
195
196         return 0;
197 }
198
199 static void bq27x00_powersupply_init(struct bq27x00_device_info *di)
200 {
201         di->bat.type = POWER_SUPPLY_TYPE_BATTERY;
202         di->bat.properties = bq27x00_battery_props;
203         di->bat.num_properties = ARRAY_SIZE(bq27x00_battery_props);
204         di->bat.get_property = bq27x00_battery_get_property;
205         di->bat.external_power_changed = NULL;
206 }
207
208 /*
209  * BQ27200 specific code
210  */
211
212 static int bq27200_read(u8 reg, int *rt_value, int b_single,
213                         struct bq27x00_device_info *di)
214 {
215         struct i2c_client *client = di->client;
216         struct i2c_msg msg[1];
217         unsigned char data[2];
218         int err;
219
220         if (!client->adapter)
221                 return -ENODEV;
222
223         msg->addr = client->addr;
224         msg->flags = 0;
225         msg->len = 1;
226         msg->buf = data;
227
228         data[0] = reg;
229         err = i2c_transfer(client->adapter, msg, 1);
230
231         if (err >= 0) {
232                 if (!b_single)
233                         msg->len = 2;
234                 else
235                         msg->len = 1;
236
237                 msg->flags = I2C_M_RD;
238                 err = i2c_transfer(client->adapter, msg, 1);
239                 if (err >= 0) {
240                         if (!b_single)
241                                 *rt_value = get_unaligned_be16(data);
242                         else
243                                 *rt_value = data[0];
244
245                         return 0;
246                 }
247         }
248         return err;
249 }
250
251 static int bq27200_battery_probe(struct i2c_client *client,
252                                  const struct i2c_device_id *id)
253 {
254         char *name;
255         struct bq27x00_device_info *di;
256         struct bq27x00_access_methods *bus;
257         int num;
258         int retval = 0;
259
260         /* Get new ID for the new battery device */
261         retval = idr_pre_get(&battery_id, GFP_KERNEL);
262         if (retval == 0)
263                 return -ENOMEM;
264         mutex_lock(&battery_mutex);
265         retval = idr_get_new(&battery_id, client, &num);
266         mutex_unlock(&battery_mutex);
267         if (retval < 0)
268                 return retval;
269
270         name = kasprintf(GFP_KERNEL, "bq27200-%d", num);
271         if (!name) {
272                 dev_err(&client->dev, "failed to allocate device name\n");
273                 retval = -ENOMEM;
274                 goto batt_failed_1;
275         }
276
277         di = kzalloc(sizeof(*di), GFP_KERNEL);
278         if (!di) {
279                 dev_err(&client->dev, "failed to allocate device info data\n");
280                 retval = -ENOMEM;
281                 goto batt_failed_2;
282         }
283         di->id = num;
284
285         bus = kzalloc(sizeof(*bus), GFP_KERNEL);
286         if (!bus) {
287                 dev_err(&client->dev, "failed to allocate access method "
288                                         "data\n");
289                 retval = -ENOMEM;
290                 goto batt_failed_3;
291         }
292
293         i2c_set_clientdata(client, di);
294         di->dev = &client->dev;
295         di->bat.name = name;
296         bus->read = &bq27200_read;
297         di->bus = bus;
298         di->client = client;
299
300         bq27x00_powersupply_init(di);
301
302         retval = power_supply_register(&client->dev, &di->bat);
303         if (retval) {
304                 dev_err(&client->dev, "failed to register battery\n");
305                 goto batt_failed_4;
306         }
307
308         dev_info(&client->dev, "support ver. %s enabled\n", DRIVER_VERSION);
309
310         return 0;
311
312 batt_failed_4:
313         kfree(bus);
314 batt_failed_3:
315         kfree(di);
316 batt_failed_2:
317         kfree(name);
318 batt_failed_1:
319         mutex_lock(&battery_mutex);
320         idr_remove(&battery_id, num);
321         mutex_unlock(&battery_mutex);
322
323         return retval;
324 }
325
326 static int bq27200_battery_remove(struct i2c_client *client)
327 {
328         struct bq27x00_device_info *di = i2c_get_clientdata(client);
329
330         power_supply_unregister(&di->bat);
331
332         kfree(di->bat.name);
333
334         mutex_lock(&battery_mutex);
335         idr_remove(&battery_id, di->id);
336         mutex_unlock(&battery_mutex);
337
338         kfree(di);
339
340         return 0;
341 }
342
343 /*
344  * Module stuff
345  */
346
347 static const struct i2c_device_id bq27200_id[] = {
348         { "bq27200", 0 },
349         {},
350 };
351
352 static struct i2c_driver bq27200_battery_driver = {
353         .driver = {
354                 .name = "bq27200-battery",
355         },
356         .probe = bq27200_battery_probe,
357         .remove = bq27200_battery_remove,
358         .id_table = bq27200_id,
359 };
360
361 static int __init bq27x00_battery_init(void)
362 {
363         int ret;
364
365         ret = i2c_add_driver(&bq27200_battery_driver);
366         if (ret)
367                 printk(KERN_ERR "Unable to register BQ27200 driver\n");
368
369         return ret;
370 }
371 module_init(bq27x00_battery_init);
372
373 static void __exit bq27x00_battery_exit(void)
374 {
375         i2c_del_driver(&bq27200_battery_driver);
376 }
377 module_exit(bq27x00_battery_exit);
378
379 MODULE_AUTHOR("Rodolfo Giometti <giometti@linux.it>");
380 MODULE_DESCRIPTION("BQ27x00 battery monitor driver");
381 MODULE_LICENSE("GPL");