Commit | Line | Data |
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b996ad0e RG |
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> | |
b996ad0e | 26 | #include <linux/i2c.h> |
5a0e3ad6 | 27 | #include <linux/slab.h> |
8aef7e8f | 28 | #include <asm/unaligned.h> |
b996ad0e | 29 | |
e20908d9 | 30 | #define DRIVER_VERSION "1.1.0" |
b996ad0e RG |
31 | |
32 | #define BQ27x00_REG_TEMP 0x06 | |
33 | #define BQ27x00_REG_VOLT 0x08 | |
b996ad0e RG |
34 | #define BQ27x00_REG_AI 0x14 |
35 | #define BQ27x00_REG_FLAGS 0x0A | |
4e924a81 GI |
36 | #define BQ27x00_REG_TTE 0x16 |
37 | #define BQ27x00_REG_TTF 0x18 | |
38 | #define BQ27x00_REG_TTECP 0x26 | |
b996ad0e | 39 | |
e20908d9 | 40 | #define BQ27000_REG_RSOC 0x0B /* Relative State-of-Charge */ |
4e924a81 | 41 | #define BQ27000_FLAG_CHGS BIT(7) |
e20908d9 GI |
42 | |
43 | #define BQ27500_REG_SOC 0x2c | |
4e924a81 GI |
44 | #define BQ27500_FLAG_DSC BIT(0) |
45 | #define BQ27500_FLAG_FC BIT(9) | |
e20908d9 | 46 | |
a2e5118c PR |
47 | #define BQ27000_RS 20 /* Resistor sense */ |
48 | ||
b996ad0e RG |
49 | /* If the system has several batteries we need a different name for each |
50 | * of them... | |
51 | */ | |
52 | static DEFINE_IDR(battery_id); | |
53 | static DEFINE_MUTEX(battery_mutex); | |
54 | ||
55 | struct bq27x00_device_info; | |
56 | struct bq27x00_access_methods { | |
a40402ef LPC |
57 | int (*read)(struct bq27x00_device_info *, u8 reg, int *rt_value, |
58 | bool single); | |
b996ad0e RG |
59 | }; |
60 | ||
e20908d9 GI |
61 | enum bq27x00_chip { BQ27000, BQ27500 }; |
62 | ||
b996ad0e RG |
63 | struct bq27x00_device_info { |
64 | struct device *dev; | |
65 | int id; | |
e20908d9 | 66 | enum bq27x00_chip chip; |
b996ad0e | 67 | |
a40402ef LPC |
68 | struct power_supply bat; |
69 | ||
70 | struct bq27x00_access_methods bus; | |
b996ad0e RG |
71 | }; |
72 | ||
73 | static enum power_supply_property bq27x00_battery_props[] = { | |
4e924a81 | 74 | POWER_SUPPLY_PROP_STATUS, |
b996ad0e RG |
75 | POWER_SUPPLY_PROP_PRESENT, |
76 | POWER_SUPPLY_PROP_VOLTAGE_NOW, | |
77 | POWER_SUPPLY_PROP_CURRENT_NOW, | |
78 | POWER_SUPPLY_PROP_CAPACITY, | |
79 | POWER_SUPPLY_PROP_TEMP, | |
4e924a81 GI |
80 | POWER_SUPPLY_PROP_TIME_TO_EMPTY_NOW, |
81 | POWER_SUPPLY_PROP_TIME_TO_EMPTY_AVG, | |
82 | POWER_SUPPLY_PROP_TIME_TO_FULL_NOW, | |
5661f334 | 83 | POWER_SUPPLY_PROP_TECHNOLOGY, |
b996ad0e RG |
84 | }; |
85 | ||
86 | /* | |
87 | * Common code for BQ27x00 devices | |
88 | */ | |
89 | ||
a40402ef LPC |
90 | static inline int bq27x00_read(struct bq27x00_device_info *di, u8 reg, |
91 | int *rt_value, bool single) | |
b996ad0e | 92 | { |
a40402ef | 93 | return di->bus.read(di, reg, rt_value, single); |
b996ad0e RG |
94 | } |
95 | ||
96 | /* | |
b4de3608 | 97 | * Return the battery temperature in tenths of degree Celsius |
b996ad0e RG |
98 | * Or < 0 if something fails. |
99 | */ | |
100 | static int bq27x00_battery_temperature(struct bq27x00_device_info *di) | |
101 | { | |
102 | int ret; | |
103 | int temp = 0; | |
104 | ||
a40402ef | 105 | ret = bq27x00_read(di, BQ27x00_REG_TEMP, &temp, false); |
b996ad0e RG |
106 | if (ret) { |
107 | dev_err(di->dev, "error reading temperature\n"); | |
108 | return ret; | |
109 | } | |
110 | ||
e20908d9 GI |
111 | if (di->chip == BQ27500) |
112 | return temp - 2731; | |
113 | else | |
0e9f3049 | 114 | return ((temp * 5) - 5463) / 2; |
b996ad0e RG |
115 | } |
116 | ||
117 | /* | |
118 | * Return the battery Voltage in milivolts | |
119 | * Or < 0 if something fails. | |
120 | */ | |
121 | static int bq27x00_battery_voltage(struct bq27x00_device_info *di) | |
122 | { | |
123 | int ret; | |
124 | int volt = 0; | |
125 | ||
a40402ef | 126 | ret = bq27x00_read(di, BQ27x00_REG_VOLT, &volt, false); |
b996ad0e RG |
127 | if (ret) { |
128 | dev_err(di->dev, "error reading voltage\n"); | |
129 | return ret; | |
130 | } | |
131 | ||
afbc74fd | 132 | return volt * 1000; |
b996ad0e RG |
133 | } |
134 | ||
135 | /* | |
136 | * Return the battery average current | |
137 | * Note that current can be negative signed as well | |
138 | * Or 0 if something fails. | |
139 | */ | |
140 | static int bq27x00_battery_current(struct bq27x00_device_info *di) | |
141 | { | |
142 | int ret; | |
143 | int curr = 0; | |
144 | int flags = 0; | |
145 | ||
a40402ef | 146 | ret = bq27x00_read(di, BQ27x00_REG_AI, &curr, false); |
b996ad0e RG |
147 | if (ret) { |
148 | dev_err(di->dev, "error reading current\n"); | |
149 | return 0; | |
150 | } | |
e20908d9 GI |
151 | |
152 | if (di->chip == BQ27500) { | |
153 | /* bq27500 returns signed value */ | |
a2e5118c | 154 | curr = (int)((s16)curr) * 1000; |
e20908d9 | 155 | } else { |
a40402ef | 156 | ret = bq27x00_read(di, BQ27x00_REG_FLAGS, &flags, false); |
e20908d9 GI |
157 | if (ret < 0) { |
158 | dev_err(di->dev, "error reading flags\n"); | |
159 | return 0; | |
160 | } | |
4e924a81 | 161 | if (flags & BQ27000_FLAG_CHGS) { |
e20908d9 | 162 | dev_dbg(di->dev, "negative current!\n"); |
afbc74fd | 163 | curr = -curr; |
e20908d9 | 164 | } |
a2e5118c | 165 | curr = curr * 3570 / BQ27000_RS; |
b996ad0e | 166 | } |
e20908d9 | 167 | |
a2e5118c | 168 | return curr; |
b996ad0e RG |
169 | } |
170 | ||
171 | /* | |
172 | * Return the battery Relative State-of-Charge | |
173 | * Or < 0 if something fails. | |
174 | */ | |
175 | static int bq27x00_battery_rsoc(struct bq27x00_device_info *di) | |
176 | { | |
177 | int ret; | |
178 | int rsoc = 0; | |
179 | ||
e20908d9 | 180 | if (di->chip == BQ27500) |
a40402ef | 181 | ret = bq27x00_read(di, BQ27500_REG_SOC, &rsoc, false); |
e20908d9 | 182 | else |
a40402ef | 183 | ret = bq27x00_read(di, BQ27000_REG_RSOC, &rsoc, true); |
b996ad0e RG |
184 | if (ret) { |
185 | dev_err(di->dev, "error reading relative State-of-Charge\n"); | |
186 | return ret; | |
187 | } | |
188 | ||
97f70c23 | 189 | return rsoc; |
b996ad0e RG |
190 | } |
191 | ||
4e924a81 GI |
192 | static int bq27x00_battery_status(struct bq27x00_device_info *di, |
193 | union power_supply_propval *val) | |
194 | { | |
195 | int flags = 0; | |
196 | int status; | |
197 | int ret; | |
198 | ||
a40402ef | 199 | ret = bq27x00_read(di, BQ27x00_REG_FLAGS, &flags, false); |
4e924a81 GI |
200 | if (ret < 0) { |
201 | dev_err(di->dev, "error reading flags\n"); | |
202 | return ret; | |
203 | } | |
204 | ||
205 | if (di->chip == BQ27500) { | |
206 | if (flags & BQ27500_FLAG_FC) | |
207 | status = POWER_SUPPLY_STATUS_FULL; | |
208 | else if (flags & BQ27500_FLAG_DSC) | |
209 | status = POWER_SUPPLY_STATUS_DISCHARGING; | |
210 | else | |
211 | status = POWER_SUPPLY_STATUS_CHARGING; | |
212 | } else { | |
213 | if (flags & BQ27000_FLAG_CHGS) | |
214 | status = POWER_SUPPLY_STATUS_CHARGING; | |
215 | else | |
216 | status = POWER_SUPPLY_STATUS_DISCHARGING; | |
217 | } | |
218 | ||
219 | val->intval = status; | |
220 | return 0; | |
221 | } | |
222 | ||
223 | /* | |
224 | * Read a time register. | |
225 | * Return < 0 if something fails. | |
226 | */ | |
227 | static int bq27x00_battery_time(struct bq27x00_device_info *di, int reg, | |
228 | union power_supply_propval *val) | |
229 | { | |
230 | int tval = 0; | |
231 | int ret; | |
232 | ||
a40402ef | 233 | ret = bq27x00_read(di, reg, &tval, false); |
4e924a81 GI |
234 | if (ret) { |
235 | dev_err(di->dev, "error reading register %02x\n", reg); | |
236 | return ret; | |
237 | } | |
238 | ||
239 | if (tval == 65535) | |
240 | return -ENODATA; | |
241 | ||
242 | val->intval = tval * 60; | |
243 | return 0; | |
244 | } | |
245 | ||
b996ad0e RG |
246 | #define to_bq27x00_device_info(x) container_of((x), \ |
247 | struct bq27x00_device_info, bat); | |
248 | ||
249 | static int bq27x00_battery_get_property(struct power_supply *psy, | |
250 | enum power_supply_property psp, | |
251 | union power_supply_propval *val) | |
252 | { | |
4e924a81 | 253 | int ret = 0; |
b996ad0e | 254 | struct bq27x00_device_info *di = to_bq27x00_device_info(psy); |
3413b4ea LPC |
255 | int voltage = bq27x00_battery_voltage(di); |
256 | ||
257 | if (psp != POWER_SUPPLY_PROP_PRESENT && voltage <= 0) | |
258 | return -ENODEV; | |
b996ad0e RG |
259 | |
260 | switch (psp) { | |
4e924a81 GI |
261 | case POWER_SUPPLY_PROP_STATUS: |
262 | ret = bq27x00_battery_status(di, val); | |
263 | break; | |
b996ad0e | 264 | case POWER_SUPPLY_PROP_VOLTAGE_NOW: |
3413b4ea LPC |
265 | val->intval = voltage; |
266 | break; | |
b996ad0e | 267 | case POWER_SUPPLY_PROP_PRESENT: |
b996ad0e | 268 | if (psp == POWER_SUPPLY_PROP_PRESENT) |
3413b4ea | 269 | val->intval = voltage <= 0 ? 0 : 1; |
b996ad0e RG |
270 | break; |
271 | case POWER_SUPPLY_PROP_CURRENT_NOW: | |
272 | val->intval = bq27x00_battery_current(di); | |
273 | break; | |
274 | case POWER_SUPPLY_PROP_CAPACITY: | |
275 | val->intval = bq27x00_battery_rsoc(di); | |
276 | break; | |
277 | case POWER_SUPPLY_PROP_TEMP: | |
278 | val->intval = bq27x00_battery_temperature(di); | |
279 | break; | |
4e924a81 GI |
280 | case POWER_SUPPLY_PROP_TIME_TO_EMPTY_NOW: |
281 | ret = bq27x00_battery_time(di, BQ27x00_REG_TTE, val); | |
282 | break; | |
283 | case POWER_SUPPLY_PROP_TIME_TO_EMPTY_AVG: | |
284 | ret = bq27x00_battery_time(di, BQ27x00_REG_TTECP, val); | |
285 | break; | |
286 | case POWER_SUPPLY_PROP_TIME_TO_FULL_NOW: | |
287 | ret = bq27x00_battery_time(di, BQ27x00_REG_TTF, val); | |
288 | break; | |
5661f334 LPC |
289 | case POWER_SUPPLY_PROP_TECHNOLOGY: |
290 | val->intval = POWER_SUPPLY_TECHNOLOGY_LION; | |
291 | break; | |
b996ad0e RG |
292 | default: |
293 | return -EINVAL; | |
294 | } | |
295 | ||
4e924a81 | 296 | return ret; |
b996ad0e RG |
297 | } |
298 | ||
a40402ef | 299 | static int bq27x00_powersupply_init(struct bq27x00_device_info *di) |
b996ad0e | 300 | { |
a40402ef LPC |
301 | int ret; |
302 | ||
b996ad0e RG |
303 | di->bat.type = POWER_SUPPLY_TYPE_BATTERY; |
304 | di->bat.properties = bq27x00_battery_props; | |
305 | di->bat.num_properties = ARRAY_SIZE(bq27x00_battery_props); | |
306 | di->bat.get_property = bq27x00_battery_get_property; | |
307 | di->bat.external_power_changed = NULL; | |
a40402ef LPC |
308 | |
309 | ret = power_supply_register(di->dev, &di->bat); | |
310 | if (ret) { | |
311 | dev_err(di->dev, "failed to register battery: %d\n", ret); | |
312 | return ret; | |
313 | } | |
314 | ||
315 | dev_info(di->dev, "support ver. %s enabled\n", DRIVER_VERSION); | |
316 | ||
317 | return 0; | |
b996ad0e RG |
318 | } |
319 | ||
320 | /* | |
e20908d9 | 321 | * i2c specific code |
b996ad0e RG |
322 | */ |
323 | ||
a40402ef LPC |
324 | static int bq27x00_read_i2c(struct bq27x00_device_info *di, u8 reg, |
325 | int *rt_value, bool single) | |
b996ad0e | 326 | { |
a40402ef | 327 | struct i2c_client *client = to_i2c_client(di->dev); |
b996ad0e RG |
328 | struct i2c_msg msg[1]; |
329 | unsigned char data[2]; | |
330 | int err; | |
331 | ||
332 | if (!client->adapter) | |
333 | return -ENODEV; | |
334 | ||
335 | msg->addr = client->addr; | |
336 | msg->flags = 0; | |
337 | msg->len = 1; | |
338 | msg->buf = data; | |
339 | ||
340 | data[0] = reg; | |
341 | err = i2c_transfer(client->adapter, msg, 1); | |
342 | ||
343 | if (err >= 0) { | |
a40402ef | 344 | if (!single) |
b996ad0e RG |
345 | msg->len = 2; |
346 | else | |
347 | msg->len = 1; | |
348 | ||
349 | msg->flags = I2C_M_RD; | |
350 | err = i2c_transfer(client->adapter, msg, 1); | |
351 | if (err >= 0) { | |
a40402ef | 352 | if (!single) |
97f70c23 | 353 | *rt_value = get_unaligned_le16(data); |
b996ad0e RG |
354 | else |
355 | *rt_value = data[0]; | |
356 | ||
357 | return 0; | |
358 | } | |
359 | } | |
360 | return err; | |
361 | } | |
362 | ||
e20908d9 | 363 | static int bq27x00_battery_probe(struct i2c_client *client, |
b996ad0e RG |
364 | const struct i2c_device_id *id) |
365 | { | |
366 | char *name; | |
367 | struct bq27x00_device_info *di; | |
b996ad0e RG |
368 | int num; |
369 | int retval = 0; | |
370 | ||
371 | /* Get new ID for the new battery device */ | |
372 | retval = idr_pre_get(&battery_id, GFP_KERNEL); | |
373 | if (retval == 0) | |
374 | return -ENOMEM; | |
375 | mutex_lock(&battery_mutex); | |
376 | retval = idr_get_new(&battery_id, client, &num); | |
377 | mutex_unlock(&battery_mutex); | |
378 | if (retval < 0) | |
379 | return retval; | |
380 | ||
e20908d9 | 381 | name = kasprintf(GFP_KERNEL, "%s-%d", id->name, num); |
b996ad0e RG |
382 | if (!name) { |
383 | dev_err(&client->dev, "failed to allocate device name\n"); | |
384 | retval = -ENOMEM; | |
385 | goto batt_failed_1; | |
386 | } | |
387 | ||
388 | di = kzalloc(sizeof(*di), GFP_KERNEL); | |
389 | if (!di) { | |
390 | dev_err(&client->dev, "failed to allocate device info data\n"); | |
391 | retval = -ENOMEM; | |
392 | goto batt_failed_2; | |
393 | } | |
a40402ef | 394 | |
b996ad0e | 395 | di->id = num; |
a40402ef | 396 | di->dev = &client->dev; |
e20908d9 | 397 | di->chip = id->driver_data; |
a40402ef LPC |
398 | di->bat.name = name; |
399 | di->bus.read = &bq27x00_read_i2c; | |
b996ad0e | 400 | |
a40402ef | 401 | if (bq27x00_powersupply_init(di)) |
b996ad0e | 402 | goto batt_failed_3; |
b996ad0e RG |
403 | |
404 | i2c_set_clientdata(client, di); | |
b996ad0e RG |
405 | |
406 | return 0; | |
407 | ||
b996ad0e RG |
408 | batt_failed_3: |
409 | kfree(di); | |
410 | batt_failed_2: | |
411 | kfree(name); | |
412 | batt_failed_1: | |
413 | mutex_lock(&battery_mutex); | |
414 | idr_remove(&battery_id, num); | |
415 | mutex_unlock(&battery_mutex); | |
416 | ||
417 | return retval; | |
418 | } | |
419 | ||
e20908d9 | 420 | static int bq27x00_battery_remove(struct i2c_client *client) |
b996ad0e RG |
421 | { |
422 | struct bq27x00_device_info *di = i2c_get_clientdata(client); | |
423 | ||
424 | power_supply_unregister(&di->bat); | |
425 | ||
426 | kfree(di->bat.name); | |
427 | ||
428 | mutex_lock(&battery_mutex); | |
429 | idr_remove(&battery_id, di->id); | |
430 | mutex_unlock(&battery_mutex); | |
431 | ||
432 | kfree(di); | |
433 | ||
434 | return 0; | |
435 | } | |
436 | ||
437 | /* | |
438 | * Module stuff | |
439 | */ | |
440 | ||
e20908d9 GI |
441 | static const struct i2c_device_id bq27x00_id[] = { |
442 | { "bq27200", BQ27000 }, /* bq27200 is same as bq27000, but with i2c */ | |
443 | { "bq27500", BQ27500 }, | |
b996ad0e RG |
444 | {}, |
445 | }; | |
446 | ||
e20908d9 | 447 | static struct i2c_driver bq27x00_battery_driver = { |
b996ad0e | 448 | .driver = { |
e20908d9 | 449 | .name = "bq27x00-battery", |
b996ad0e | 450 | }, |
e20908d9 GI |
451 | .probe = bq27x00_battery_probe, |
452 | .remove = bq27x00_battery_remove, | |
453 | .id_table = bq27x00_id, | |
b996ad0e RG |
454 | }; |
455 | ||
456 | static int __init bq27x00_battery_init(void) | |
457 | { | |
458 | int ret; | |
459 | ||
e20908d9 | 460 | ret = i2c_add_driver(&bq27x00_battery_driver); |
b996ad0e | 461 | if (ret) |
e20908d9 | 462 | printk(KERN_ERR "Unable to register BQ27x00 driver\n"); |
b996ad0e RG |
463 | |
464 | return ret; | |
465 | } | |
466 | module_init(bq27x00_battery_init); | |
467 | ||
468 | static void __exit bq27x00_battery_exit(void) | |
469 | { | |
e20908d9 | 470 | i2c_del_driver(&bq27x00_battery_driver); |
b996ad0e RG |
471 | } |
472 | module_exit(bq27x00_battery_exit); | |
473 | ||
474 | MODULE_AUTHOR("Rodolfo Giometti <giometti@linux.it>"); | |
475 | MODULE_DESCRIPTION("BQ27x00 battery monitor driver"); | |
476 | MODULE_LICENSE("GPL"); |