Commit | Line | Data |
---|---|---|
a7640bfa RK |
1 | /* |
2 | * Gas Gauge driver for TI's BQ20Z75 | |
3 | * | |
4 | * Copyright (c) 2010, NVIDIA Corporation. | |
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 as published by | |
8 | * the Free Software Foundation; either version 2 of the License, or | |
9 | * (at your option) any later version. | |
10 | * | |
11 | * This program is distributed in the hope that it will be useful, but WITHOUT | |
12 | * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or | |
13 | * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for | |
14 | * more details. | |
15 | * | |
16 | * You should have received a copy of the GNU General Public License along | |
17 | * with this program; if not, write to the Free Software Foundation, Inc., | |
18 | * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA. | |
19 | */ | |
20 | ||
21 | #include <linux/init.h> | |
22 | #include <linux/module.h> | |
23 | #include <linux/kernel.h> | |
24 | #include <linux/err.h> | |
25 | #include <linux/power_supply.h> | |
26 | #include <linux/i2c.h> | |
27 | #include <linux/slab.h> | |
28 | ||
29 | enum { | |
30 | REG_MANUFACTURER_DATA, | |
31 | REG_TEMPERATURE, | |
32 | REG_VOLTAGE, | |
33 | REG_CURRENT, | |
34 | REG_CAPACITY, | |
35 | REG_TIME_TO_EMPTY, | |
36 | REG_TIME_TO_FULL, | |
37 | REG_STATUS, | |
38 | REG_CYCLE_COUNT, | |
39 | REG_SERIAL_NUMBER | |
40 | }; | |
41 | ||
42 | /* manufacturer access defines */ | |
43 | #define MANUFACTURER_ACCESS_STATUS 0x0006 | |
44 | #define MANUFACTURER_ACCESS_SLEEP 0x0011 | |
45 | ||
46 | /* battery status value bits */ | |
47 | #define BATTERY_CHARGING 0x40 | |
48 | #define BATTERY_FULL_CHARGED 0x20 | |
49 | #define BATTERY_FULL_DISCHARGED 0x10 | |
50 | ||
51 | #define BQ20Z75_DATA(_psp, _addr, _min_value, _max_value) { \ | |
52 | .psp = _psp, \ | |
53 | .addr = _addr, \ | |
54 | .min_value = _min_value, \ | |
55 | .max_value = _max_value, \ | |
56 | } | |
57 | ||
58 | static const struct bq20z75_device_data { | |
59 | enum power_supply_property psp; | |
60 | u8 addr; | |
61 | int min_value; | |
62 | int max_value; | |
63 | } bq20z75_data[] = { | |
64 | [REG_MANUFACTURER_DATA] = | |
65 | BQ20Z75_DATA(POWER_SUPPLY_PROP_PRESENT, 0x00, 0, 65535), | |
66 | [REG_TEMPERATURE] = | |
67 | BQ20Z75_DATA(POWER_SUPPLY_PROP_TEMP, 0x08, 0, 65535), | |
68 | [REG_VOLTAGE] = | |
69 | BQ20Z75_DATA(POWER_SUPPLY_PROP_VOLTAGE_NOW, 0x09, 0, 20000), | |
70 | [REG_CURRENT] = | |
71 | BQ20Z75_DATA(POWER_SUPPLY_PROP_CURRENT_NOW, 0x0A, -32768, | |
72 | 32767), | |
73 | [REG_CAPACITY] = | |
74 | BQ20Z75_DATA(POWER_SUPPLY_PROP_CAPACITY, 0x0E, 0, 100), | |
75 | [REG_TIME_TO_EMPTY] = | |
76 | BQ20Z75_DATA(POWER_SUPPLY_PROP_TIME_TO_EMPTY_AVG, 0x12, 0, | |
77 | 65535), | |
78 | [REG_TIME_TO_FULL] = | |
79 | BQ20Z75_DATA(POWER_SUPPLY_PROP_TIME_TO_FULL_AVG, 0x13, 0, | |
80 | 65535), | |
81 | [REG_STATUS] = | |
82 | BQ20Z75_DATA(POWER_SUPPLY_PROP_STATUS, 0x16, 0, 65535), | |
83 | [REG_CYCLE_COUNT] = | |
84 | BQ20Z75_DATA(POWER_SUPPLY_PROP_CYCLE_COUNT, 0x17, 0, 65535), | |
85 | [REG_SERIAL_NUMBER] = | |
86 | BQ20Z75_DATA(POWER_SUPPLY_PROP_SERIAL_NUMBER, 0x1C, 0, 65535), | |
87 | }; | |
88 | ||
89 | static enum power_supply_property bq20z75_properties[] = { | |
90 | POWER_SUPPLY_PROP_STATUS, | |
91 | POWER_SUPPLY_PROP_HEALTH, | |
92 | POWER_SUPPLY_PROP_PRESENT, | |
93 | POWER_SUPPLY_PROP_TECHNOLOGY, | |
94 | POWER_SUPPLY_PROP_CYCLE_COUNT, | |
95 | POWER_SUPPLY_PROP_VOLTAGE_NOW, | |
96 | POWER_SUPPLY_PROP_CURRENT_NOW, | |
97 | POWER_SUPPLY_PROP_CAPACITY, | |
98 | POWER_SUPPLY_PROP_TEMP, | |
99 | POWER_SUPPLY_PROP_TIME_TO_EMPTY_AVG, | |
100 | POWER_SUPPLY_PROP_TIME_TO_FULL_AVG, | |
101 | POWER_SUPPLY_PROP_SERIAL_NUMBER, | |
102 | }; | |
103 | ||
104 | struct bq20z75_info { | |
105 | struct i2c_client *client; | |
106 | struct power_supply power_supply; | |
107 | }; | |
108 | ||
109 | static int bq20z75_get_battery_presence_and_health( | |
110 | struct i2c_client *client, enum power_supply_property psp, | |
111 | union power_supply_propval *val) | |
112 | { | |
113 | s32 ret; | |
114 | ||
115 | /* Write to ManufacturerAccess with | |
116 | * ManufacturerAccess command and then | |
117 | * read the status */ | |
118 | ret = i2c_smbus_write_word_data(client, | |
119 | bq20z75_data[REG_MANUFACTURER_DATA].addr, | |
120 | MANUFACTURER_ACCESS_STATUS); | |
121 | if (ret < 0) { | |
122 | dev_err(&client->dev, | |
123 | "%s: i2c write for battery presence failed\n", | |
124 | __func__); | |
125 | return -ENODEV; | |
126 | } | |
127 | ||
128 | ret = i2c_smbus_read_word_data(client, | |
129 | bq20z75_data[REG_MANUFACTURER_DATA].addr); | |
130 | if (ret < 0) { | |
131 | dev_err(&client->dev, | |
132 | "%s: i2c read for battery presence failed\n", | |
133 | __func__); | |
134 | return -EIO; | |
135 | } | |
136 | ||
137 | if (ret < bq20z75_data[REG_MANUFACTURER_DATA].min_value || | |
138 | ret > bq20z75_data[REG_MANUFACTURER_DATA].max_value) { | |
139 | val->intval = 0; | |
140 | return 0; | |
141 | } | |
142 | ||
143 | /* Mask the upper nibble of 2nd byte and | |
144 | * lower byte of response then | |
145 | * shift the result by 8 to get status*/ | |
146 | ret &= 0x0F00; | |
147 | ret >>= 8; | |
148 | if (psp == POWER_SUPPLY_PROP_PRESENT) { | |
149 | if (ret == 0x0F) | |
150 | /* battery removed */ | |
151 | val->intval = 0; | |
152 | else | |
153 | val->intval = 1; | |
154 | } else if (psp == POWER_SUPPLY_PROP_HEALTH) { | |
155 | if (ret == 0x09) | |
156 | val->intval = POWER_SUPPLY_HEALTH_UNSPEC_FAILURE; | |
157 | else if (ret == 0x0B) | |
158 | val->intval = POWER_SUPPLY_HEALTH_OVERHEAT; | |
159 | else if (ret == 0x0C) | |
160 | val->intval = POWER_SUPPLY_HEALTH_DEAD; | |
161 | else | |
162 | val->intval = POWER_SUPPLY_HEALTH_GOOD; | |
163 | } | |
164 | ||
165 | return 0; | |
166 | } | |
167 | ||
168 | static int bq20z75_get_battery_property(struct i2c_client *client, | |
169 | int reg_offset, enum power_supply_property psp, | |
170 | union power_supply_propval *val) | |
171 | { | |
172 | s32 ret; | |
173 | ||
174 | ret = i2c_smbus_read_word_data(client, | |
175 | bq20z75_data[reg_offset].addr); | |
176 | if (ret < 0) { | |
177 | dev_err(&client->dev, | |
178 | "%s: i2c read for %d failed\n", __func__, reg_offset); | |
179 | return -EIO; | |
180 | } | |
181 | ||
182 | if (ret >= bq20z75_data[reg_offset].min_value && | |
183 | ret <= bq20z75_data[reg_offset].max_value) { | |
184 | val->intval = ret; | |
185 | if (psp == POWER_SUPPLY_PROP_STATUS) { | |
186 | if (ret & BATTERY_CHARGING) | |
187 | val->intval = POWER_SUPPLY_STATUS_CHARGING; | |
188 | else if (ret & BATTERY_FULL_CHARGED) | |
189 | val->intval = POWER_SUPPLY_STATUS_FULL; | |
190 | else if (ret & BATTERY_FULL_DISCHARGED) | |
191 | val->intval = POWER_SUPPLY_STATUS_NOT_CHARGING; | |
192 | else | |
193 | val->intval = POWER_SUPPLY_STATUS_DISCHARGING; | |
194 | } | |
195 | /* bq20z75 provides battery tempreture in 0.1°K | |
196 | * so convert it to °C */ | |
197 | else if (psp == POWER_SUPPLY_PROP_TEMP) | |
198 | val->intval = ret - 2731; | |
199 | } else { | |
200 | if (psp == POWER_SUPPLY_PROP_STATUS) | |
201 | val->intval = POWER_SUPPLY_STATUS_UNKNOWN; | |
202 | else | |
203 | val->intval = 0; | |
204 | } | |
205 | ||
206 | return 0; | |
207 | } | |
208 | ||
209 | static int bq20z75_get_battery_capacity(struct i2c_client *client, | |
210 | union power_supply_propval *val) | |
211 | { | |
212 | s32 ret; | |
213 | ||
214 | ret = i2c_smbus_read_byte_data(client, bq20z75_data[REG_CAPACITY].addr); | |
215 | if (ret < 0) { | |
216 | dev_err(&client->dev, | |
217 | "%s: i2c read for %d failed\n", __func__, REG_CAPACITY); | |
218 | return -EIO; | |
219 | } | |
220 | ||
221 | /* bq20z75 spec says that this can be >100 % | |
222 | * even if max value is 100 % */ | |
223 | val->intval = min(ret, 100); | |
224 | ||
225 | return 0; | |
226 | } | |
227 | ||
228 | static int bq20z75_get_property(struct power_supply *psy, | |
229 | enum power_supply_property psp, | |
230 | union power_supply_propval *val) | |
231 | { | |
232 | int count; | |
233 | int ret; | |
234 | struct bq20z75_info *bq20z75_device = container_of(psy, | |
235 | struct bq20z75_info, power_supply); | |
236 | struct i2c_client *client = bq20z75_device->client; | |
237 | ||
238 | switch (psp) { | |
239 | case POWER_SUPPLY_PROP_PRESENT: | |
240 | case POWER_SUPPLY_PROP_HEALTH: | |
241 | ret = bq20z75_get_battery_presence_and_health(client, psp, val); | |
242 | if (ret) | |
243 | return ret; | |
244 | break; | |
245 | ||
246 | case POWER_SUPPLY_PROP_TECHNOLOGY: | |
247 | val->intval = POWER_SUPPLY_TECHNOLOGY_LION; | |
248 | break; | |
249 | ||
250 | case POWER_SUPPLY_PROP_CAPACITY: | |
251 | ret = bq20z75_get_battery_capacity(client, val); | |
252 | if (ret) | |
253 | return ret; | |
254 | break; | |
255 | ||
256 | case POWER_SUPPLY_PROP_STATUS: | |
257 | case POWER_SUPPLY_PROP_CYCLE_COUNT: | |
258 | case POWER_SUPPLY_PROP_VOLTAGE_NOW: | |
259 | case POWER_SUPPLY_PROP_CURRENT_NOW: | |
260 | case POWER_SUPPLY_PROP_TEMP: | |
261 | case POWER_SUPPLY_PROP_TIME_TO_EMPTY_AVG: | |
262 | case POWER_SUPPLY_PROP_TIME_TO_FULL_AVG: | |
263 | case POWER_SUPPLY_PROP_SERIAL_NUMBER: | |
264 | for (count = 0; count < ARRAY_SIZE(bq20z75_data); count++) { | |
265 | if (psp == bq20z75_data[count].psp) | |
266 | break; | |
267 | } | |
268 | ||
269 | ret = bq20z75_get_battery_property(client, count, psp, val); | |
270 | if (ret) | |
271 | return ret; | |
272 | break; | |
273 | ||
274 | default: | |
275 | dev_err(&client->dev, | |
276 | "%s: INVALID property\n", __func__); | |
277 | return -EINVAL; | |
278 | } | |
279 | ||
280 | dev_dbg(&client->dev, | |
281 | "%s: property = %d, value = %d\n", __func__, psp, val->intval); | |
282 | ||
283 | return 0; | |
284 | } | |
285 | ||
286 | static int bq20z75_probe(struct i2c_client *client, | |
287 | const struct i2c_device_id *id) | |
288 | { | |
289 | struct bq20z75_info *bq20z75_device; | |
290 | int rc; | |
291 | ||
292 | bq20z75_device = kzalloc(sizeof(struct bq20z75_info), GFP_KERNEL); | |
293 | if (!bq20z75_device) | |
294 | return -ENOMEM; | |
295 | ||
296 | bq20z75_device->client = client; | |
297 | bq20z75_device->power_supply.name = "battery"; | |
298 | bq20z75_device->power_supply.type = POWER_SUPPLY_TYPE_BATTERY; | |
299 | bq20z75_device->power_supply.properties = bq20z75_properties; | |
300 | bq20z75_device->power_supply.num_properties = | |
301 | ARRAY_SIZE(bq20z75_properties); | |
302 | bq20z75_device->power_supply.get_property = bq20z75_get_property; | |
303 | ||
304 | i2c_set_clientdata(client, bq20z75_device); | |
305 | ||
306 | rc = power_supply_register(&client->dev, &bq20z75_device->power_supply); | |
307 | if (rc) { | |
308 | dev_err(&client->dev, | |
309 | "%s: Failed to register power supply\n", __func__); | |
310 | kfree(bq20z75_device); | |
311 | return rc; | |
312 | } | |
313 | ||
314 | dev_info(&client->dev, | |
315 | "%s: battery gas gauge device registered\n", client->name); | |
316 | ||
317 | return 0; | |
318 | } | |
319 | ||
320 | static int bq20z75_remove(struct i2c_client *client) | |
321 | { | |
322 | struct bq20z75_info *bq20z75_device = i2c_get_clientdata(client); | |
323 | ||
324 | power_supply_unregister(&bq20z75_device->power_supply); | |
325 | kfree(bq20z75_device); | |
326 | bq20z75_device = NULL; | |
327 | ||
328 | return 0; | |
329 | } | |
330 | ||
331 | #if defined CONFIG_PM | |
332 | static int bq20z75_suspend(struct i2c_client *client, | |
333 | pm_message_t state) | |
334 | { | |
335 | s32 ret; | |
336 | ||
337 | /* write to manufacturer access with sleep command */ | |
338 | ret = i2c_smbus_write_word_data(client, | |
339 | bq20z75_data[REG_MANUFACTURER_DATA].addr, | |
340 | MANUFACTURER_ACCESS_SLEEP); | |
341 | if (ret < 0) { | |
342 | dev_err(&client->dev, | |
343 | "%s: i2c write for %d failed\n", | |
344 | __func__, MANUFACTURER_ACCESS_SLEEP); | |
345 | return -EIO; | |
346 | } | |
347 | ||
348 | return 0; | |
349 | } | |
350 | #else | |
351 | #define bq20z75_suspend NULL | |
352 | #endif | |
353 | /* any smbus transaction will wake up bq20z75 */ | |
354 | #define bq20z75_resume NULL | |
355 | ||
356 | static const struct i2c_device_id bq20z75_id[] = { | |
357 | { "bq20z75", 0 }, | |
358 | {} | |
359 | }; | |
360 | ||
361 | static struct i2c_driver bq20z75_battery_driver = { | |
362 | .probe = bq20z75_probe, | |
363 | .remove = bq20z75_remove, | |
364 | .suspend = bq20z75_suspend, | |
365 | .resume = bq20z75_resume, | |
366 | .id_table = bq20z75_id, | |
367 | .driver = { | |
368 | .name = "bq20z75-battery", | |
369 | }, | |
370 | }; | |
371 | ||
372 | static int __init bq20z75_battery_init(void) | |
373 | { | |
374 | return i2c_add_driver(&bq20z75_battery_driver); | |
375 | } | |
376 | module_init(bq20z75_battery_init); | |
377 | ||
378 | static void __exit bq20z75_battery_exit(void) | |
379 | { | |
380 | i2c_del_driver(&bq20z75_battery_driver); | |
381 | } | |
382 | module_exit(bq20z75_battery_exit); | |
383 | ||
384 | MODULE_DESCRIPTION("BQ20z75 battery monitor driver"); | |
385 | MODULE_LICENSE("GPL"); |