Commit | Line | Data |
---|---|---|
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> |
8aef7e8f | 27 | #include <asm/unaligned.h> |
b996ad0e | 28 | |
e20908d9 | 29 | #define DRIVER_VERSION "1.1.0" |
b996ad0e RG |
30 | |
31 | #define BQ27x00_REG_TEMP 0x06 | |
32 | #define BQ27x00_REG_VOLT 0x08 | |
b996ad0e RG |
33 | #define BQ27x00_REG_AI 0x14 |
34 | #define BQ27x00_REG_FLAGS 0x0A | |
4e924a81 GI |
35 | #define BQ27x00_REG_TTE 0x16 |
36 | #define BQ27x00_REG_TTF 0x18 | |
37 | #define BQ27x00_REG_TTECP 0x26 | |
b996ad0e | 38 | |
e20908d9 | 39 | #define BQ27000_REG_RSOC 0x0B /* Relative State-of-Charge */ |
4e924a81 | 40 | #define BQ27000_FLAG_CHGS BIT(7) |
e20908d9 GI |
41 | |
42 | #define BQ27500_REG_SOC 0x2c | |
4e924a81 GI |
43 | #define BQ27500_FLAG_DSC BIT(0) |
44 | #define BQ27500_FLAG_FC BIT(9) | |
e20908d9 | 45 | |
b996ad0e RG |
46 | /* If the system has several batteries we need a different name for each |
47 | * of them... | |
48 | */ | |
49 | static DEFINE_IDR(battery_id); | |
50 | static DEFINE_MUTEX(battery_mutex); | |
51 | ||
52 | struct bq27x00_device_info; | |
53 | struct bq27x00_access_methods { | |
54 | int (*read)(u8 reg, int *rt_value, int b_single, | |
55 | struct bq27x00_device_info *di); | |
56 | }; | |
57 | ||
e20908d9 GI |
58 | enum bq27x00_chip { BQ27000, BQ27500 }; |
59 | ||
b996ad0e RG |
60 | struct bq27x00_device_info { |
61 | struct device *dev; | |
62 | int id; | |
b996ad0e RG |
63 | struct bq27x00_access_methods *bus; |
64 | struct power_supply bat; | |
e20908d9 | 65 | enum bq27x00_chip chip; |
b996ad0e RG |
66 | |
67 | struct i2c_client *client; | |
68 | }; | |
69 | ||
70 | static enum power_supply_property bq27x00_battery_props[] = { | |
4e924a81 | 71 | POWER_SUPPLY_PROP_STATUS, |
b996ad0e RG |
72 | POWER_SUPPLY_PROP_PRESENT, |
73 | POWER_SUPPLY_PROP_VOLTAGE_NOW, | |
74 | POWER_SUPPLY_PROP_CURRENT_NOW, | |
75 | POWER_SUPPLY_PROP_CAPACITY, | |
76 | POWER_SUPPLY_PROP_TEMP, | |
4e924a81 GI |
77 | POWER_SUPPLY_PROP_TIME_TO_EMPTY_NOW, |
78 | POWER_SUPPLY_PROP_TIME_TO_EMPTY_AVG, | |
79 | POWER_SUPPLY_PROP_TIME_TO_FULL_NOW, | |
b996ad0e RG |
80 | }; |
81 | ||
82 | /* | |
83 | * Common code for BQ27x00 devices | |
84 | */ | |
85 | ||
86 | static int bq27x00_read(u8 reg, int *rt_value, int b_single, | |
87 | struct bq27x00_device_info *di) | |
88 | { | |
97f70c23 | 89 | return di->bus->read(reg, rt_value, b_single, di); |
b996ad0e RG |
90 | } |
91 | ||
92 | /* | |
b4de3608 | 93 | * Return the battery temperature in tenths of degree Celsius |
b996ad0e RG |
94 | * Or < 0 if something fails. |
95 | */ | |
96 | static int bq27x00_battery_temperature(struct bq27x00_device_info *di) | |
97 | { | |
98 | int ret; | |
99 | int temp = 0; | |
100 | ||
101 | ret = bq27x00_read(BQ27x00_REG_TEMP, &temp, 0, di); | |
102 | if (ret) { | |
103 | dev_err(di->dev, "error reading temperature\n"); | |
104 | return ret; | |
105 | } | |
106 | ||
e20908d9 GI |
107 | if (di->chip == BQ27500) |
108 | return temp - 2731; | |
109 | else | |
110 | return ((temp >> 2) - 273) * 10; | |
b996ad0e RG |
111 | } |
112 | ||
113 | /* | |
114 | * Return the battery Voltage in milivolts | |
115 | * Or < 0 if something fails. | |
116 | */ | |
117 | static int bq27x00_battery_voltage(struct bq27x00_device_info *di) | |
118 | { | |
119 | int ret; | |
120 | int volt = 0; | |
121 | ||
122 | ret = bq27x00_read(BQ27x00_REG_VOLT, &volt, 0, di); | |
123 | if (ret) { | |
124 | dev_err(di->dev, "error reading voltage\n"); | |
125 | return ret; | |
126 | } | |
127 | ||
afbc74fd | 128 | return volt * 1000; |
b996ad0e RG |
129 | } |
130 | ||
131 | /* | |
132 | * Return the battery average current | |
133 | * Note that current can be negative signed as well | |
134 | * Or 0 if something fails. | |
135 | */ | |
136 | static int bq27x00_battery_current(struct bq27x00_device_info *di) | |
137 | { | |
138 | int ret; | |
139 | int curr = 0; | |
140 | int flags = 0; | |
141 | ||
142 | ret = bq27x00_read(BQ27x00_REG_AI, &curr, 0, di); | |
143 | if (ret) { | |
144 | dev_err(di->dev, "error reading current\n"); | |
145 | return 0; | |
146 | } | |
e20908d9 GI |
147 | |
148 | if (di->chip == BQ27500) { | |
149 | /* bq27500 returns signed value */ | |
150 | curr = (int)(s16)curr; | |
151 | } else { | |
152 | ret = bq27x00_read(BQ27x00_REG_FLAGS, &flags, 0, di); | |
153 | if (ret < 0) { | |
154 | dev_err(di->dev, "error reading flags\n"); | |
155 | return 0; | |
156 | } | |
4e924a81 | 157 | if (flags & BQ27000_FLAG_CHGS) { |
e20908d9 | 158 | dev_dbg(di->dev, "negative current!\n"); |
afbc74fd | 159 | curr = -curr; |
e20908d9 | 160 | } |
b996ad0e | 161 | } |
e20908d9 | 162 | |
afbc74fd | 163 | return curr * 1000; |
b996ad0e RG |
164 | } |
165 | ||
166 | /* | |
167 | * Return the battery Relative State-of-Charge | |
168 | * Or < 0 if something fails. | |
169 | */ | |
170 | static int bq27x00_battery_rsoc(struct bq27x00_device_info *di) | |
171 | { | |
172 | int ret; | |
173 | int rsoc = 0; | |
174 | ||
e20908d9 GI |
175 | if (di->chip == BQ27500) |
176 | ret = bq27x00_read(BQ27500_REG_SOC, &rsoc, 0, di); | |
177 | else | |
178 | ret = bq27x00_read(BQ27000_REG_RSOC, &rsoc, 1, di); | |
b996ad0e RG |
179 | if (ret) { |
180 | dev_err(di->dev, "error reading relative State-of-Charge\n"); | |
181 | return ret; | |
182 | } | |
183 | ||
97f70c23 | 184 | return rsoc; |
b996ad0e RG |
185 | } |
186 | ||
4e924a81 GI |
187 | static int bq27x00_battery_status(struct bq27x00_device_info *di, |
188 | union power_supply_propval *val) | |
189 | { | |
190 | int flags = 0; | |
191 | int status; | |
192 | int ret; | |
193 | ||
194 | ret = bq27x00_read(BQ27x00_REG_FLAGS, &flags, 0, di); | |
195 | if (ret < 0) { | |
196 | dev_err(di->dev, "error reading flags\n"); | |
197 | return ret; | |
198 | } | |
199 | ||
200 | if (di->chip == BQ27500) { | |
201 | if (flags & BQ27500_FLAG_FC) | |
202 | status = POWER_SUPPLY_STATUS_FULL; | |
203 | else if (flags & BQ27500_FLAG_DSC) | |
204 | status = POWER_SUPPLY_STATUS_DISCHARGING; | |
205 | else | |
206 | status = POWER_SUPPLY_STATUS_CHARGING; | |
207 | } else { | |
208 | if (flags & BQ27000_FLAG_CHGS) | |
209 | status = POWER_SUPPLY_STATUS_CHARGING; | |
210 | else | |
211 | status = POWER_SUPPLY_STATUS_DISCHARGING; | |
212 | } | |
213 | ||
214 | val->intval = status; | |
215 | return 0; | |
216 | } | |
217 | ||
218 | /* | |
219 | * Read a time register. | |
220 | * Return < 0 if something fails. | |
221 | */ | |
222 | static int bq27x00_battery_time(struct bq27x00_device_info *di, int reg, | |
223 | union power_supply_propval *val) | |
224 | { | |
225 | int tval = 0; | |
226 | int ret; | |
227 | ||
228 | ret = bq27x00_read(reg, &tval, 0, di); | |
229 | if (ret) { | |
230 | dev_err(di->dev, "error reading register %02x\n", reg); | |
231 | return ret; | |
232 | } | |
233 | ||
234 | if (tval == 65535) | |
235 | return -ENODATA; | |
236 | ||
237 | val->intval = tval * 60; | |
238 | return 0; | |
239 | } | |
240 | ||
b996ad0e RG |
241 | #define to_bq27x00_device_info(x) container_of((x), \ |
242 | struct bq27x00_device_info, bat); | |
243 | ||
244 | static int bq27x00_battery_get_property(struct power_supply *psy, | |
245 | enum power_supply_property psp, | |
246 | union power_supply_propval *val) | |
247 | { | |
4e924a81 | 248 | int ret = 0; |
b996ad0e RG |
249 | struct bq27x00_device_info *di = to_bq27x00_device_info(psy); |
250 | ||
251 | switch (psp) { | |
4e924a81 GI |
252 | case POWER_SUPPLY_PROP_STATUS: |
253 | ret = bq27x00_battery_status(di, val); | |
254 | break; | |
b996ad0e RG |
255 | case POWER_SUPPLY_PROP_VOLTAGE_NOW: |
256 | case POWER_SUPPLY_PROP_PRESENT: | |
257 | val->intval = bq27x00_battery_voltage(di); | |
258 | if (psp == POWER_SUPPLY_PROP_PRESENT) | |
259 | val->intval = val->intval <= 0 ? 0 : 1; | |
260 | break; | |
261 | case POWER_SUPPLY_PROP_CURRENT_NOW: | |
262 | val->intval = bq27x00_battery_current(di); | |
263 | break; | |
264 | case POWER_SUPPLY_PROP_CAPACITY: | |
265 | val->intval = bq27x00_battery_rsoc(di); | |
266 | break; | |
267 | case POWER_SUPPLY_PROP_TEMP: | |
268 | val->intval = bq27x00_battery_temperature(di); | |
269 | break; | |
4e924a81 GI |
270 | case POWER_SUPPLY_PROP_TIME_TO_EMPTY_NOW: |
271 | ret = bq27x00_battery_time(di, BQ27x00_REG_TTE, val); | |
272 | break; | |
273 | case POWER_SUPPLY_PROP_TIME_TO_EMPTY_AVG: | |
274 | ret = bq27x00_battery_time(di, BQ27x00_REG_TTECP, val); | |
275 | break; | |
276 | case POWER_SUPPLY_PROP_TIME_TO_FULL_NOW: | |
277 | ret = bq27x00_battery_time(di, BQ27x00_REG_TTF, val); | |
278 | break; | |
b996ad0e RG |
279 | default: |
280 | return -EINVAL; | |
281 | } | |
282 | ||
4e924a81 | 283 | return ret; |
b996ad0e RG |
284 | } |
285 | ||
286 | static void bq27x00_powersupply_init(struct bq27x00_device_info *di) | |
287 | { | |
288 | di->bat.type = POWER_SUPPLY_TYPE_BATTERY; | |
289 | di->bat.properties = bq27x00_battery_props; | |
290 | di->bat.num_properties = ARRAY_SIZE(bq27x00_battery_props); | |
291 | di->bat.get_property = bq27x00_battery_get_property; | |
292 | di->bat.external_power_changed = NULL; | |
293 | } | |
294 | ||
295 | /* | |
e20908d9 | 296 | * i2c specific code |
b996ad0e RG |
297 | */ |
298 | ||
e20908d9 | 299 | static int bq27x00_read_i2c(u8 reg, int *rt_value, int b_single, |
b996ad0e RG |
300 | struct bq27x00_device_info *di) |
301 | { | |
302 | struct i2c_client *client = di->client; | |
303 | struct i2c_msg msg[1]; | |
304 | unsigned char data[2]; | |
305 | int err; | |
306 | ||
307 | if (!client->adapter) | |
308 | return -ENODEV; | |
309 | ||
310 | msg->addr = client->addr; | |
311 | msg->flags = 0; | |
312 | msg->len = 1; | |
313 | msg->buf = data; | |
314 | ||
315 | data[0] = reg; | |
316 | err = i2c_transfer(client->adapter, msg, 1); | |
317 | ||
318 | if (err >= 0) { | |
319 | if (!b_single) | |
320 | msg->len = 2; | |
321 | else | |
322 | msg->len = 1; | |
323 | ||
324 | msg->flags = I2C_M_RD; | |
325 | err = i2c_transfer(client->adapter, msg, 1); | |
326 | if (err >= 0) { | |
327 | if (!b_single) | |
97f70c23 | 328 | *rt_value = get_unaligned_le16(data); |
b996ad0e RG |
329 | else |
330 | *rt_value = data[0]; | |
331 | ||
332 | return 0; | |
333 | } | |
334 | } | |
335 | return err; | |
336 | } | |
337 | ||
e20908d9 | 338 | static int bq27x00_battery_probe(struct i2c_client *client, |
b996ad0e RG |
339 | const struct i2c_device_id *id) |
340 | { | |
341 | char *name; | |
342 | struct bq27x00_device_info *di; | |
343 | struct bq27x00_access_methods *bus; | |
344 | int num; | |
345 | int retval = 0; | |
346 | ||
347 | /* Get new ID for the new battery device */ | |
348 | retval = idr_pre_get(&battery_id, GFP_KERNEL); | |
349 | if (retval == 0) | |
350 | return -ENOMEM; | |
351 | mutex_lock(&battery_mutex); | |
352 | retval = idr_get_new(&battery_id, client, &num); | |
353 | mutex_unlock(&battery_mutex); | |
354 | if (retval < 0) | |
355 | return retval; | |
356 | ||
e20908d9 | 357 | name = kasprintf(GFP_KERNEL, "%s-%d", id->name, num); |
b996ad0e RG |
358 | if (!name) { |
359 | dev_err(&client->dev, "failed to allocate device name\n"); | |
360 | retval = -ENOMEM; | |
361 | goto batt_failed_1; | |
362 | } | |
363 | ||
364 | di = kzalloc(sizeof(*di), GFP_KERNEL); | |
365 | if (!di) { | |
366 | dev_err(&client->dev, "failed to allocate device info data\n"); | |
367 | retval = -ENOMEM; | |
368 | goto batt_failed_2; | |
369 | } | |
370 | di->id = num; | |
e20908d9 | 371 | di->chip = id->driver_data; |
b996ad0e RG |
372 | |
373 | bus = kzalloc(sizeof(*bus), GFP_KERNEL); | |
374 | if (!bus) { | |
375 | dev_err(&client->dev, "failed to allocate access method " | |
376 | "data\n"); | |
377 | retval = -ENOMEM; | |
378 | goto batt_failed_3; | |
379 | } | |
380 | ||
381 | i2c_set_clientdata(client, di); | |
382 | di->dev = &client->dev; | |
383 | di->bat.name = name; | |
e20908d9 | 384 | bus->read = &bq27x00_read_i2c; |
b996ad0e RG |
385 | di->bus = bus; |
386 | di->client = client; | |
387 | ||
388 | bq27x00_powersupply_init(di); | |
389 | ||
390 | retval = power_supply_register(&client->dev, &di->bat); | |
391 | if (retval) { | |
392 | dev_err(&client->dev, "failed to register battery\n"); | |
393 | goto batt_failed_4; | |
394 | } | |
395 | ||
396 | dev_info(&client->dev, "support ver. %s enabled\n", DRIVER_VERSION); | |
397 | ||
398 | return 0; | |
399 | ||
400 | batt_failed_4: | |
401 | kfree(bus); | |
402 | batt_failed_3: | |
403 | kfree(di); | |
404 | batt_failed_2: | |
405 | kfree(name); | |
406 | batt_failed_1: | |
407 | mutex_lock(&battery_mutex); | |
408 | idr_remove(&battery_id, num); | |
409 | mutex_unlock(&battery_mutex); | |
410 | ||
411 | return retval; | |
412 | } | |
413 | ||
e20908d9 | 414 | static int bq27x00_battery_remove(struct i2c_client *client) |
b996ad0e RG |
415 | { |
416 | struct bq27x00_device_info *di = i2c_get_clientdata(client); | |
417 | ||
418 | power_supply_unregister(&di->bat); | |
419 | ||
420 | kfree(di->bat.name); | |
421 | ||
422 | mutex_lock(&battery_mutex); | |
423 | idr_remove(&battery_id, di->id); | |
424 | mutex_unlock(&battery_mutex); | |
425 | ||
426 | kfree(di); | |
427 | ||
428 | return 0; | |
429 | } | |
430 | ||
431 | /* | |
432 | * Module stuff | |
433 | */ | |
434 | ||
e20908d9 GI |
435 | static const struct i2c_device_id bq27x00_id[] = { |
436 | { "bq27200", BQ27000 }, /* bq27200 is same as bq27000, but with i2c */ | |
437 | { "bq27500", BQ27500 }, | |
b996ad0e RG |
438 | {}, |
439 | }; | |
440 | ||
e20908d9 | 441 | static struct i2c_driver bq27x00_battery_driver = { |
b996ad0e | 442 | .driver = { |
e20908d9 | 443 | .name = "bq27x00-battery", |
b996ad0e | 444 | }, |
e20908d9 GI |
445 | .probe = bq27x00_battery_probe, |
446 | .remove = bq27x00_battery_remove, | |
447 | .id_table = bq27x00_id, | |
b996ad0e RG |
448 | }; |
449 | ||
450 | static int __init bq27x00_battery_init(void) | |
451 | { | |
452 | int ret; | |
453 | ||
e20908d9 | 454 | ret = i2c_add_driver(&bq27x00_battery_driver); |
b996ad0e | 455 | if (ret) |
e20908d9 | 456 | printk(KERN_ERR "Unable to register BQ27x00 driver\n"); |
b996ad0e RG |
457 | |
458 | return ret; | |
459 | } | |
460 | module_init(bq27x00_battery_init); | |
461 | ||
462 | static void __exit bq27x00_battery_exit(void) | |
463 | { | |
e20908d9 | 464 | i2c_del_driver(&bq27x00_battery_driver); |
b996ad0e RG |
465 | } |
466 | module_exit(bq27x00_battery_exit); | |
467 | ||
468 | MODULE_AUTHOR("Rodolfo Giometti <giometti@linux.it>"); | |
469 | MODULE_DESCRIPTION("BQ27x00 battery monitor driver"); | |
470 | MODULE_LICENSE("GPL"); |