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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  * Copyright (C) 2010-2011 Lars-Peter Clausen <lars@metafoo.de>
7  * Copyright (C) 2011 Pali Rohár <pali.rohar@gmail.com>
8  *
9  * Based on a previous work by Copyright (C) 2008 Texas Instruments, Inc.
10  *
11  * This package is free software; you can redistribute it and/or modify
12  * it under the terms of the GNU General Public License version 2 as
13  * published by the Free Software Foundation.
14  *
15  * THIS PACKAGE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR
16  * IMPLIED WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED
17  * WARRANTIES OF MERCHANTIBILITY AND FITNESS FOR A PARTICULAR PURPOSE.
18  *
19  */
20 
21 /*
22  * Datasheets:
23  * http://focus.ti.com/docs/prod/folders/print/bq27000.html
24  * http://focus.ti.com/docs/prod/folders/print/bq27500.html
25  * http://www.ti.com/product/bq27425-g1
26  */
27 
28 #include <linux/module.h>
29 #include <linux/param.h>
30 #include <linux/jiffies.h>
31 #include <linux/workqueue.h>
32 #include <linux/delay.h>
33 #include <linux/platform_device.h>
34 #include <linux/power_supply.h>
35 #include <linux/idr.h>
36 #include <linux/i2c.h>
37 #include <linux/slab.h>
38 #include <asm/unaligned.h>
39 
40 #include <linux/power/bq27x00_battery.h>
41 
42 #define DRIVER_VERSION			"1.2.0"
43 
44 #define BQ27x00_REG_TEMP		0x06
45 #define BQ27x00_REG_VOLT		0x08
46 #define BQ27x00_REG_AI			0x14
47 #define BQ27x00_REG_FLAGS		0x0A
48 #define BQ27x00_REG_TTE			0x16
49 #define BQ27x00_REG_TTF			0x18
50 #define BQ27x00_REG_TTECP		0x26
51 #define BQ27x00_REG_NAC			0x0C /* Nominal available capacity */
52 #define BQ27x00_REG_LMD			0x12 /* Last measured discharge */
53 #define BQ27x00_REG_CYCT		0x2A /* Cycle count total */
54 #define BQ27x00_REG_AE			0x22 /* Available energy */
55 #define BQ27x00_POWER_AVG		0x24
56 
57 #define BQ27000_REG_RSOC		0x0B /* Relative State-of-Charge */
58 #define BQ27000_REG_ILMD		0x76 /* Initial last measured discharge */
59 #define BQ27000_FLAG_EDVF		BIT(0) /* Final End-of-Discharge-Voltage flag */
60 #define BQ27000_FLAG_EDV1		BIT(1) /* First End-of-Discharge-Voltage flag */
61 #define BQ27000_FLAG_CI			BIT(4) /* Capacity Inaccurate flag */
62 #define BQ27000_FLAG_FC			BIT(5)
63 #define BQ27000_FLAG_CHGS		BIT(7) /* Charge state flag */
64 
65 #define BQ27500_REG_SOC			0x2C
66 #define BQ27500_REG_DCAP		0x3C /* Design capacity */
67 #define BQ27500_FLAG_DSC		BIT(0)
68 #define BQ27500_FLAG_SOCF		BIT(1) /* State-of-Charge threshold final */
69 #define BQ27500_FLAG_SOC1		BIT(2) /* State-of-Charge threshold 1 */
70 #define BQ27500_FLAG_FC			BIT(9)
71 #define BQ27500_FLAG_OTC		BIT(15)
72 
73 /* bq27425 register addresses are same as bq27x00 addresses minus 4 */
74 #define BQ27425_REG_OFFSET		0x04
75 #define BQ27425_REG_SOC			0x18 /* Register address plus offset */
76 
77 #define BQ27000_RS			20 /* Resistor sense */
78 #define BQ27x00_POWER_CONSTANT		(256 * 29200 / 1000)
79 
80 struct bq27x00_device_info;
81 struct bq27x00_access_methods {
82 	int (*read)(struct bq27x00_device_info *di, u8 reg, bool single);
83 };
84 
85 enum bq27x00_chip { BQ27000, BQ27500, BQ27425};
86 
87 struct bq27x00_reg_cache {
88 	int temperature;
89 	int time_to_empty;
90 	int time_to_empty_avg;
91 	int time_to_full;
92 	int charge_full;
93 	int cycle_count;
94 	int capacity;
95 	int energy;
96 	int flags;
97 	int power_avg;
98 	int health;
99 };
100 
101 struct bq27x00_device_info {
102 	struct device 		*dev;
103 	int			id;
104 	enum bq27x00_chip	chip;
105 
106 	struct bq27x00_reg_cache cache;
107 	int charge_design_full;
108 
109 	unsigned long last_update;
110 	struct delayed_work work;
111 
112 	struct power_supply	bat;
113 
114 	struct bq27x00_access_methods bus;
115 
116 	struct mutex lock;
117 };
118 
119 static enum power_supply_property bq27x00_battery_props[] = {
120 	POWER_SUPPLY_PROP_STATUS,
121 	POWER_SUPPLY_PROP_PRESENT,
122 	POWER_SUPPLY_PROP_VOLTAGE_NOW,
123 	POWER_SUPPLY_PROP_CURRENT_NOW,
124 	POWER_SUPPLY_PROP_CAPACITY,
125 	POWER_SUPPLY_PROP_CAPACITY_LEVEL,
126 	POWER_SUPPLY_PROP_TEMP,
127 	POWER_SUPPLY_PROP_TIME_TO_EMPTY_NOW,
128 	POWER_SUPPLY_PROP_TIME_TO_EMPTY_AVG,
129 	POWER_SUPPLY_PROP_TIME_TO_FULL_NOW,
130 	POWER_SUPPLY_PROP_TECHNOLOGY,
131 	POWER_SUPPLY_PROP_CHARGE_FULL,
132 	POWER_SUPPLY_PROP_CHARGE_NOW,
133 	POWER_SUPPLY_PROP_CHARGE_FULL_DESIGN,
134 	POWER_SUPPLY_PROP_CYCLE_COUNT,
135 	POWER_SUPPLY_PROP_ENERGY_NOW,
136 	POWER_SUPPLY_PROP_POWER_AVG,
137 	POWER_SUPPLY_PROP_HEALTH,
138 };
139 
140 static enum power_supply_property bq27425_battery_props[] = {
141 	POWER_SUPPLY_PROP_STATUS,
142 	POWER_SUPPLY_PROP_PRESENT,
143 	POWER_SUPPLY_PROP_VOLTAGE_NOW,
144 	POWER_SUPPLY_PROP_CURRENT_NOW,
145 	POWER_SUPPLY_PROP_CAPACITY,
146 	POWER_SUPPLY_PROP_CAPACITY_LEVEL,
147 	POWER_SUPPLY_PROP_TEMP,
148 	POWER_SUPPLY_PROP_TECHNOLOGY,
149 	POWER_SUPPLY_PROP_CHARGE_FULL,
150 	POWER_SUPPLY_PROP_CHARGE_NOW,
151 	POWER_SUPPLY_PROP_CHARGE_FULL_DESIGN,
152 };
153 
154 static unsigned int poll_interval = 360;
155 module_param(poll_interval, uint, 0644);
156 MODULE_PARM_DESC(poll_interval, "battery poll interval in seconds - " \
157 				"0 disables polling");
158 
159 /*
160  * Common code for BQ27x00 devices
161  */
162 
bq27x00_read(struct bq27x00_device_info * di,u8 reg,bool single)163 static inline int bq27x00_read(struct bq27x00_device_info *di, u8 reg,
164 		bool single)
165 {
166 	if (di->chip == BQ27425)
167 		return di->bus.read(di, reg - BQ27425_REG_OFFSET, single);
168 	return di->bus.read(di, reg, single);
169 }
170 
171 /*
172  * Higher versions of the chip like BQ27425 and BQ27500
173  * differ from BQ27000 and BQ27200 in calculation of certain
174  * parameters. Hence we need to check for the chip type.
175  */
bq27xxx_is_chip_version_higher(struct bq27x00_device_info * di)176 static bool bq27xxx_is_chip_version_higher(struct bq27x00_device_info *di)
177 {
178 	if (di->chip == BQ27425 || di->chip == BQ27500)
179 		return true;
180 	return false;
181 }
182 
183 /*
184  * Return the battery Relative State-of-Charge
185  * Or < 0 if something fails.
186  */
bq27x00_battery_read_rsoc(struct bq27x00_device_info * di)187 static int bq27x00_battery_read_rsoc(struct bq27x00_device_info *di)
188 {
189 	int rsoc;
190 
191 	if (di->chip == BQ27500)
192 		rsoc = bq27x00_read(di, BQ27500_REG_SOC, false);
193 	else if (di->chip == BQ27425)
194 		rsoc = bq27x00_read(di, BQ27425_REG_SOC, false);
195 	else
196 		rsoc = bq27x00_read(di, BQ27000_REG_RSOC, true);
197 
198 	if (rsoc < 0)
199 		dev_dbg(di->dev, "error reading relative State-of-Charge\n");
200 
201 	return rsoc;
202 }
203 
204 /*
205  * Return a battery charge value in µAh
206  * Or < 0 if something fails.
207  */
bq27x00_battery_read_charge(struct bq27x00_device_info * di,u8 reg)208 static int bq27x00_battery_read_charge(struct bq27x00_device_info *di, u8 reg)
209 {
210 	int charge;
211 
212 	charge = bq27x00_read(di, reg, false);
213 	if (charge < 0) {
214 		dev_dbg(di->dev, "error reading charge register %02x: %d\n",
215 			reg, charge);
216 		return charge;
217 	}
218 
219 	if (bq27xxx_is_chip_version_higher(di))
220 		charge *= 1000;
221 	else
222 		charge = charge * 3570 / BQ27000_RS;
223 
224 	return charge;
225 }
226 
227 /*
228  * Return the battery Nominal available capaciy in µAh
229  * Or < 0 if something fails.
230  */
bq27x00_battery_read_nac(struct bq27x00_device_info * di)231 static inline int bq27x00_battery_read_nac(struct bq27x00_device_info *di)
232 {
233 	int flags;
234 	bool is_bq27500 = di->chip == BQ27500;
235 	bool is_higher = bq27xxx_is_chip_version_higher(di);
236 
237 	flags = bq27x00_read(di, BQ27x00_REG_FLAGS, !is_bq27500);
238 	if (flags >= 0 && !is_higher && (flags & BQ27000_FLAG_CI))
239 		return -ENODATA;
240 
241 	return bq27x00_battery_read_charge(di, BQ27x00_REG_NAC);
242 }
243 
244 /*
245  * Return the battery Last measured discharge in µAh
246  * Or < 0 if something fails.
247  */
bq27x00_battery_read_lmd(struct bq27x00_device_info * di)248 static inline int bq27x00_battery_read_lmd(struct bq27x00_device_info *di)
249 {
250 	return bq27x00_battery_read_charge(di, BQ27x00_REG_LMD);
251 }
252 
253 /*
254  * Return the battery Initial last measured discharge in µAh
255  * Or < 0 if something fails.
256  */
bq27x00_battery_read_ilmd(struct bq27x00_device_info * di)257 static int bq27x00_battery_read_ilmd(struct bq27x00_device_info *di)
258 {
259 	int ilmd;
260 
261 	if (bq27xxx_is_chip_version_higher(di))
262 		ilmd = bq27x00_read(di, BQ27500_REG_DCAP, false);
263 	else
264 		ilmd = bq27x00_read(di, BQ27000_REG_ILMD, true);
265 
266 	if (ilmd < 0) {
267 		dev_dbg(di->dev, "error reading initial last measured discharge\n");
268 		return ilmd;
269 	}
270 
271 	if (bq27xxx_is_chip_version_higher(di))
272 		ilmd *= 1000;
273 	else
274 		ilmd = ilmd * 256 * 3570 / BQ27000_RS;
275 
276 	return ilmd;
277 }
278 
279 /*
280  * Return the battery Available energy in µWh
281  * Or < 0 if something fails.
282  */
bq27x00_battery_read_energy(struct bq27x00_device_info * di)283 static int bq27x00_battery_read_energy(struct bq27x00_device_info *di)
284 {
285 	int ae;
286 
287 	ae = bq27x00_read(di, BQ27x00_REG_AE, false);
288 	if (ae < 0) {
289 		dev_dbg(di->dev, "error reading available energy\n");
290 		return ae;
291 	}
292 
293 	if (di->chip == BQ27500)
294 		ae *= 1000;
295 	else
296 		ae = ae * 29200 / BQ27000_RS;
297 
298 	return ae;
299 }
300 
301 /*
302  * Return the battery temperature in tenths of degree Kelvin
303  * Or < 0 if something fails.
304  */
bq27x00_battery_read_temperature(struct bq27x00_device_info * di)305 static int bq27x00_battery_read_temperature(struct bq27x00_device_info *di)
306 {
307 	int temp;
308 
309 	temp = bq27x00_read(di, BQ27x00_REG_TEMP, false);
310 	if (temp < 0) {
311 		dev_err(di->dev, "error reading temperature\n");
312 		return temp;
313 	}
314 
315 	if (!bq27xxx_is_chip_version_higher(di))
316 		temp = 5 * temp / 2;
317 
318 	return temp;
319 }
320 
321 /*
322  * Return the battery Cycle count total
323  * Or < 0 if something fails.
324  */
bq27x00_battery_read_cyct(struct bq27x00_device_info * di)325 static int bq27x00_battery_read_cyct(struct bq27x00_device_info *di)
326 {
327 	int cyct;
328 
329 	cyct = bq27x00_read(di, BQ27x00_REG_CYCT, false);
330 	if (cyct < 0)
331 		dev_err(di->dev, "error reading cycle count total\n");
332 
333 	return cyct;
334 }
335 
336 /*
337  * Read a time register.
338  * Return < 0 if something fails.
339  */
bq27x00_battery_read_time(struct bq27x00_device_info * di,u8 reg)340 static int bq27x00_battery_read_time(struct bq27x00_device_info *di, u8 reg)
341 {
342 	int tval;
343 
344 	tval = bq27x00_read(di, reg, false);
345 	if (tval < 0) {
346 		dev_dbg(di->dev, "error reading time register %02x: %d\n",
347 			reg, tval);
348 		return tval;
349 	}
350 
351 	if (tval == 65535)
352 		return -ENODATA;
353 
354 	return tval * 60;
355 }
356 
357 /*
358  * Read a power avg register.
359  * Return < 0 if something fails.
360  */
bq27x00_battery_read_pwr_avg(struct bq27x00_device_info * di,u8 reg)361 static int bq27x00_battery_read_pwr_avg(struct bq27x00_device_info *di, u8 reg)
362 {
363 	int tval;
364 
365 	tval = bq27x00_read(di, reg, false);
366 	if (tval < 0) {
367 		dev_err(di->dev, "error reading power avg rgister  %02x: %d\n",
368 			reg, tval);
369 		return tval;
370 	}
371 
372 	if (di->chip == BQ27500)
373 		return tval;
374 	else
375 		return (tval * BQ27x00_POWER_CONSTANT) / BQ27000_RS;
376 }
377 
378 /*
379  * Read flag register.
380  * Return < 0 if something fails.
381  */
bq27x00_battery_read_health(struct bq27x00_device_info * di)382 static int bq27x00_battery_read_health(struct bq27x00_device_info *di)
383 {
384 	int tval;
385 
386 	tval = bq27x00_read(di, BQ27x00_REG_FLAGS, false);
387 	if (tval < 0) {
388 		dev_err(di->dev, "error reading flag register:%d\n", tval);
389 		return tval;
390 	}
391 
392 	if ((di->chip == BQ27500)) {
393 		if (tval & BQ27500_FLAG_SOCF)
394 			tval = POWER_SUPPLY_HEALTH_DEAD;
395 		else if (tval & BQ27500_FLAG_OTC)
396 			tval = POWER_SUPPLY_HEALTH_OVERHEAT;
397 		else
398 			tval = POWER_SUPPLY_HEALTH_GOOD;
399 		return tval;
400 	} else {
401 		if (tval & BQ27000_FLAG_EDV1)
402 			tval = POWER_SUPPLY_HEALTH_DEAD;
403 		else
404 			tval = POWER_SUPPLY_HEALTH_GOOD;
405 		return tval;
406 	}
407 
408 	return -1;
409 }
410 
bq27x00_update(struct bq27x00_device_info * di)411 static void bq27x00_update(struct bq27x00_device_info *di)
412 {
413 	struct bq27x00_reg_cache cache = {0, };
414 	bool is_bq27500 = di->chip == BQ27500;
415 	bool is_bq27425 = di->chip == BQ27425;
416 
417 	cache.flags = bq27x00_read(di, BQ27x00_REG_FLAGS, !is_bq27500);
418 	if (cache.flags >= 0) {
419 		if (!is_bq27500 && !is_bq27425
420 				&& (cache.flags & BQ27000_FLAG_CI)) {
421 			dev_info(di->dev, "battery is not calibrated! ignoring capacity values\n");
422 			cache.capacity = -ENODATA;
423 			cache.energy = -ENODATA;
424 			cache.time_to_empty = -ENODATA;
425 			cache.time_to_empty_avg = -ENODATA;
426 			cache.time_to_full = -ENODATA;
427 			cache.charge_full = -ENODATA;
428 			cache.health = -ENODATA;
429 		} else {
430 			cache.capacity = bq27x00_battery_read_rsoc(di);
431 			if (!is_bq27425) {
432 				cache.energy = bq27x00_battery_read_energy(di);
433 				cache.time_to_empty =
434 					bq27x00_battery_read_time(di,
435 							BQ27x00_REG_TTE);
436 				cache.time_to_empty_avg =
437 					bq27x00_battery_read_time(di,
438 							BQ27x00_REG_TTECP);
439 				cache.time_to_full =
440 					bq27x00_battery_read_time(di,
441 							BQ27x00_REG_TTF);
442 			}
443 			cache.charge_full = bq27x00_battery_read_lmd(di);
444 			cache.health = bq27x00_battery_read_health(di);
445 		}
446 		cache.temperature = bq27x00_battery_read_temperature(di);
447 		if (!is_bq27425)
448 			cache.cycle_count = bq27x00_battery_read_cyct(di);
449 		cache.power_avg =
450 			bq27x00_battery_read_pwr_avg(di, BQ27x00_POWER_AVG);
451 
452 		/* We only have to read charge design full once */
453 		if (di->charge_design_full <= 0)
454 			di->charge_design_full = bq27x00_battery_read_ilmd(di);
455 	}
456 
457 	if (memcmp(&di->cache, &cache, sizeof(cache)) != 0) {
458 		di->cache = cache;
459 		power_supply_changed(&di->bat);
460 	}
461 
462 	di->last_update = jiffies;
463 }
464 
bq27x00_battery_poll(struct work_struct * work)465 static void bq27x00_battery_poll(struct work_struct *work)
466 {
467 	struct bq27x00_device_info *di =
468 		container_of(work, struct bq27x00_device_info, work.work);
469 
470 	bq27x00_update(di);
471 
472 	if (poll_interval > 0) {
473 		/* The timer does not have to be accurate. */
474 		set_timer_slack(&di->work.timer, poll_interval * HZ / 4);
475 		schedule_delayed_work(&di->work, poll_interval * HZ);
476 	}
477 }
478 
479 /*
480  * Return the battery average current in µA
481  * Note that current can be negative signed as well
482  * Or 0 if something fails.
483  */
bq27x00_battery_current(struct bq27x00_device_info * di,union power_supply_propval * val)484 static int bq27x00_battery_current(struct bq27x00_device_info *di,
485 	union power_supply_propval *val)
486 {
487 	int curr;
488 	int flags;
489 
490 	curr = bq27x00_read(di, BQ27x00_REG_AI, false);
491 	if (curr < 0) {
492 		dev_err(di->dev, "error reading current\n");
493 		return curr;
494 	}
495 
496 	if (bq27xxx_is_chip_version_higher(di)) {
497 		/* bq27500 returns signed value */
498 		val->intval = (int)((s16)curr) * 1000;
499 	} else {
500 		flags = bq27x00_read(di, BQ27x00_REG_FLAGS, false);
501 		if (flags & BQ27000_FLAG_CHGS) {
502 			dev_dbg(di->dev, "negative current!\n");
503 			curr = -curr;
504 		}
505 
506 		val->intval = curr * 3570 / BQ27000_RS;
507 	}
508 
509 	return 0;
510 }
511 
bq27x00_battery_status(struct bq27x00_device_info * di,union power_supply_propval * val)512 static int bq27x00_battery_status(struct bq27x00_device_info *di,
513 	union power_supply_propval *val)
514 {
515 	int status;
516 
517 	if (bq27xxx_is_chip_version_higher(di)) {
518 		if (di->cache.flags & BQ27500_FLAG_FC)
519 			status = POWER_SUPPLY_STATUS_FULL;
520 		else if (di->cache.flags & BQ27500_FLAG_DSC)
521 			status = POWER_SUPPLY_STATUS_DISCHARGING;
522 		else
523 			status = POWER_SUPPLY_STATUS_CHARGING;
524 	} else {
525 		if (di->cache.flags & BQ27000_FLAG_FC)
526 			status = POWER_SUPPLY_STATUS_FULL;
527 		else if (di->cache.flags & BQ27000_FLAG_CHGS)
528 			status = POWER_SUPPLY_STATUS_CHARGING;
529 		else if (power_supply_am_i_supplied(&di->bat))
530 			status = POWER_SUPPLY_STATUS_NOT_CHARGING;
531 		else
532 			status = POWER_SUPPLY_STATUS_DISCHARGING;
533 	}
534 
535 	val->intval = status;
536 
537 	return 0;
538 }
539 
bq27x00_battery_capacity_level(struct bq27x00_device_info * di,union power_supply_propval * val)540 static int bq27x00_battery_capacity_level(struct bq27x00_device_info *di,
541 	union power_supply_propval *val)
542 {
543 	int level;
544 
545 	if (bq27xxx_is_chip_version_higher(di)) {
546 		if (di->cache.flags & BQ27500_FLAG_FC)
547 			level = POWER_SUPPLY_CAPACITY_LEVEL_FULL;
548 		else if (di->cache.flags & BQ27500_FLAG_SOC1)
549 			level = POWER_SUPPLY_CAPACITY_LEVEL_LOW;
550 		else if (di->cache.flags & BQ27500_FLAG_SOCF)
551 			level = POWER_SUPPLY_CAPACITY_LEVEL_CRITICAL;
552 		else
553 			level = POWER_SUPPLY_CAPACITY_LEVEL_NORMAL;
554 	} else {
555 		if (di->cache.flags & BQ27000_FLAG_FC)
556 			level = POWER_SUPPLY_CAPACITY_LEVEL_FULL;
557 		else if (di->cache.flags & BQ27000_FLAG_EDV1)
558 			level = POWER_SUPPLY_CAPACITY_LEVEL_LOW;
559 		else if (di->cache.flags & BQ27000_FLAG_EDVF)
560 			level = POWER_SUPPLY_CAPACITY_LEVEL_CRITICAL;
561 		else
562 			level = POWER_SUPPLY_CAPACITY_LEVEL_NORMAL;
563 	}
564 
565 	val->intval = level;
566 
567 	return 0;
568 }
569 
570 /*
571  * Return the battery Voltage in millivolts
572  * Or < 0 if something fails.
573  */
bq27x00_battery_voltage(struct bq27x00_device_info * di,union power_supply_propval * val)574 static int bq27x00_battery_voltage(struct bq27x00_device_info *di,
575 	union power_supply_propval *val)
576 {
577 	int volt;
578 
579 	volt = bq27x00_read(di, BQ27x00_REG_VOLT, false);
580 	if (volt < 0) {
581 		dev_err(di->dev, "error reading voltage\n");
582 		return volt;
583 	}
584 
585 	val->intval = volt * 1000;
586 
587 	return 0;
588 }
589 
bq27x00_simple_value(int value,union power_supply_propval * val)590 static int bq27x00_simple_value(int value,
591 	union power_supply_propval *val)
592 {
593 	if (value < 0)
594 		return value;
595 
596 	val->intval = value;
597 
598 	return 0;
599 }
600 
601 #define to_bq27x00_device_info(x) container_of((x), \
602 				struct bq27x00_device_info, bat);
603 
bq27x00_battery_get_property(struct power_supply * psy,enum power_supply_property psp,union power_supply_propval * val)604 static int bq27x00_battery_get_property(struct power_supply *psy,
605 					enum power_supply_property psp,
606 					union power_supply_propval *val)
607 {
608 	int ret = 0;
609 	struct bq27x00_device_info *di = to_bq27x00_device_info(psy);
610 
611 	mutex_lock(&di->lock);
612 	if (time_is_before_jiffies(di->last_update + 5 * HZ)) {
613 		cancel_delayed_work_sync(&di->work);
614 		bq27x00_battery_poll(&di->work.work);
615 	}
616 	mutex_unlock(&di->lock);
617 
618 	if (psp != POWER_SUPPLY_PROP_PRESENT && di->cache.flags < 0)
619 		return -ENODEV;
620 
621 	switch (psp) {
622 	case POWER_SUPPLY_PROP_STATUS:
623 		ret = bq27x00_battery_status(di, val);
624 		break;
625 	case POWER_SUPPLY_PROP_VOLTAGE_NOW:
626 		ret = bq27x00_battery_voltage(di, val);
627 		break;
628 	case POWER_SUPPLY_PROP_PRESENT:
629 		val->intval = di->cache.flags < 0 ? 0 : 1;
630 		break;
631 	case POWER_SUPPLY_PROP_CURRENT_NOW:
632 		ret = bq27x00_battery_current(di, val);
633 		break;
634 	case POWER_SUPPLY_PROP_CAPACITY:
635 		ret = bq27x00_simple_value(di->cache.capacity, val);
636 		break;
637 	case POWER_SUPPLY_PROP_CAPACITY_LEVEL:
638 		ret = bq27x00_battery_capacity_level(di, val);
639 		break;
640 	case POWER_SUPPLY_PROP_TEMP:
641 		ret = bq27x00_simple_value(di->cache.temperature, val);
642 		if (ret == 0)
643 			val->intval -= 2731;
644 		break;
645 	case POWER_SUPPLY_PROP_TIME_TO_EMPTY_NOW:
646 		ret = bq27x00_simple_value(di->cache.time_to_empty, val);
647 		break;
648 	case POWER_SUPPLY_PROP_TIME_TO_EMPTY_AVG:
649 		ret = bq27x00_simple_value(di->cache.time_to_empty_avg, val);
650 		break;
651 	case POWER_SUPPLY_PROP_TIME_TO_FULL_NOW:
652 		ret = bq27x00_simple_value(di->cache.time_to_full, val);
653 		break;
654 	case POWER_SUPPLY_PROP_TECHNOLOGY:
655 		val->intval = POWER_SUPPLY_TECHNOLOGY_LION;
656 		break;
657 	case POWER_SUPPLY_PROP_CHARGE_NOW:
658 		ret = bq27x00_simple_value(bq27x00_battery_read_nac(di), val);
659 		break;
660 	case POWER_SUPPLY_PROP_CHARGE_FULL:
661 		ret = bq27x00_simple_value(di->cache.charge_full, val);
662 		break;
663 	case POWER_SUPPLY_PROP_CHARGE_FULL_DESIGN:
664 		ret = bq27x00_simple_value(di->charge_design_full, val);
665 		break;
666 	case POWER_SUPPLY_PROP_CYCLE_COUNT:
667 		ret = bq27x00_simple_value(di->cache.cycle_count, val);
668 		break;
669 	case POWER_SUPPLY_PROP_ENERGY_NOW:
670 		ret = bq27x00_simple_value(di->cache.energy, val);
671 		break;
672 	case POWER_SUPPLY_PROP_POWER_AVG:
673 		ret = bq27x00_simple_value(di->cache.power_avg, val);
674 		break;
675 	case POWER_SUPPLY_PROP_HEALTH:
676 		ret = bq27x00_simple_value(di->cache.health, val);
677 		break;
678 	default:
679 		return -EINVAL;
680 	}
681 
682 	return ret;
683 }
684 
bq27x00_external_power_changed(struct power_supply * psy)685 static void bq27x00_external_power_changed(struct power_supply *psy)
686 {
687 	struct bq27x00_device_info *di = to_bq27x00_device_info(psy);
688 
689 	cancel_delayed_work_sync(&di->work);
690 	schedule_delayed_work(&di->work, 0);
691 }
692 
bq27x00_powersupply_init(struct bq27x00_device_info * di)693 static int bq27x00_powersupply_init(struct bq27x00_device_info *di)
694 {
695 	int ret;
696 
697 	di->bat.type = POWER_SUPPLY_TYPE_BATTERY;
698 	if (di->chip == BQ27425) {
699 		di->bat.properties = bq27425_battery_props;
700 		di->bat.num_properties = ARRAY_SIZE(bq27425_battery_props);
701 	} else {
702 		di->bat.properties = bq27x00_battery_props;
703 		di->bat.num_properties = ARRAY_SIZE(bq27x00_battery_props);
704 	}
705 	di->bat.get_property = bq27x00_battery_get_property;
706 	di->bat.external_power_changed = bq27x00_external_power_changed;
707 
708 	INIT_DELAYED_WORK(&di->work, bq27x00_battery_poll);
709 	mutex_init(&di->lock);
710 
711 	ret = power_supply_register(di->dev, &di->bat);
712 	if (ret) {
713 		dev_err(di->dev, "failed to register battery: %d\n", ret);
714 		return ret;
715 	}
716 
717 	dev_info(di->dev, "support ver. %s enabled\n", DRIVER_VERSION);
718 
719 	bq27x00_update(di);
720 
721 	return 0;
722 }
723 
bq27x00_powersupply_unregister(struct bq27x00_device_info * di)724 static void bq27x00_powersupply_unregister(struct bq27x00_device_info *di)
725 {
726 	/*
727 	 * power_supply_unregister call bq27x00_battery_get_property which
728 	 * call bq27x00_battery_poll.
729 	 * Make sure that bq27x00_battery_poll will not call
730 	 * schedule_delayed_work again after unregister (which cause OOPS).
731 	 */
732 	poll_interval = 0;
733 
734 	cancel_delayed_work_sync(&di->work);
735 
736 	power_supply_unregister(&di->bat);
737 
738 	mutex_destroy(&di->lock);
739 }
740 
741 
742 /* i2c specific code */
743 #ifdef CONFIG_BATTERY_BQ27X00_I2C
744 
745 /* If the system has several batteries we need a different name for each
746  * of them...
747  */
748 static DEFINE_IDR(battery_id);
749 static DEFINE_MUTEX(battery_mutex);
750 
bq27x00_read_i2c(struct bq27x00_device_info * di,u8 reg,bool single)751 static int bq27x00_read_i2c(struct bq27x00_device_info *di, u8 reg, bool single)
752 {
753 	struct i2c_client *client = to_i2c_client(di->dev);
754 	struct i2c_msg msg[2];
755 	unsigned char data[2];
756 	int ret;
757 
758 	if (!client->adapter)
759 		return -ENODEV;
760 
761 	msg[0].addr = client->addr;
762 	msg[0].flags = 0;
763 	msg[0].buf = &reg;
764 	msg[0].len = sizeof(reg);
765 	msg[1].addr = client->addr;
766 	msg[1].flags = I2C_M_RD;
767 	msg[1].buf = data;
768 	if (single)
769 		msg[1].len = 1;
770 	else
771 		msg[1].len = 2;
772 
773 	ret = i2c_transfer(client->adapter, msg, ARRAY_SIZE(msg));
774 	if (ret < 0)
775 		return ret;
776 
777 	if (!single)
778 		ret = get_unaligned_le16(data);
779 	else
780 		ret = data[0];
781 
782 	return ret;
783 }
784 
bq27x00_battery_probe(struct i2c_client * client,const struct i2c_device_id * id)785 static int bq27x00_battery_probe(struct i2c_client *client,
786 				 const struct i2c_device_id *id)
787 {
788 	char *name;
789 	struct bq27x00_device_info *di;
790 	int num;
791 	int retval = 0;
792 
793 	/* Get new ID for the new battery device */
794 	mutex_lock(&battery_mutex);
795 	num = idr_alloc(&battery_id, client, 0, 0, GFP_KERNEL);
796 	mutex_unlock(&battery_mutex);
797 	if (num < 0)
798 		return num;
799 
800 	name = kasprintf(GFP_KERNEL, "%s-%d", id->name, num);
801 	if (!name) {
802 		dev_err(&client->dev, "failed to allocate device name\n");
803 		retval = -ENOMEM;
804 		goto batt_failed_1;
805 	}
806 
807 	di = kzalloc(sizeof(*di), GFP_KERNEL);
808 	if (!di) {
809 		dev_err(&client->dev, "failed to allocate device info data\n");
810 		retval = -ENOMEM;
811 		goto batt_failed_2;
812 	}
813 
814 	di->id = num;
815 	di->dev = &client->dev;
816 	di->chip = id->driver_data;
817 	di->bat.name = name;
818 	di->bus.read = &bq27x00_read_i2c;
819 
820 	retval = bq27x00_powersupply_init(di);
821 	if (retval)
822 		goto batt_failed_3;
823 
824 	i2c_set_clientdata(client, di);
825 
826 	return 0;
827 
828 batt_failed_3:
829 	kfree(di);
830 batt_failed_2:
831 	kfree(name);
832 batt_failed_1:
833 	mutex_lock(&battery_mutex);
834 	idr_remove(&battery_id, num);
835 	mutex_unlock(&battery_mutex);
836 
837 	return retval;
838 }
839 
bq27x00_battery_remove(struct i2c_client * client)840 static int bq27x00_battery_remove(struct i2c_client *client)
841 {
842 	struct bq27x00_device_info *di = i2c_get_clientdata(client);
843 
844 	bq27x00_powersupply_unregister(di);
845 
846 	kfree(di->bat.name);
847 
848 	mutex_lock(&battery_mutex);
849 	idr_remove(&battery_id, di->id);
850 	mutex_unlock(&battery_mutex);
851 
852 	kfree(di);
853 
854 	return 0;
855 }
856 
857 static const struct i2c_device_id bq27x00_id[] = {
858 	{ "bq27200", BQ27000 },	/* bq27200 is same as bq27000, but with i2c */
859 	{ "bq27500", BQ27500 },
860 	{ "bq27425", BQ27425 },
861 	{},
862 };
863 MODULE_DEVICE_TABLE(i2c, bq27x00_id);
864 
865 static struct i2c_driver bq27x00_battery_driver = {
866 	.driver = {
867 		.name = "bq27x00-battery",
868 	},
869 	.probe = bq27x00_battery_probe,
870 	.remove = bq27x00_battery_remove,
871 	.id_table = bq27x00_id,
872 };
873 
bq27x00_battery_i2c_init(void)874 static inline int bq27x00_battery_i2c_init(void)
875 {
876 	int ret = i2c_add_driver(&bq27x00_battery_driver);
877 	if (ret)
878 		printk(KERN_ERR "Unable to register BQ27x00 i2c driver\n");
879 
880 	return ret;
881 }
882 
bq27x00_battery_i2c_exit(void)883 static inline void bq27x00_battery_i2c_exit(void)
884 {
885 	i2c_del_driver(&bq27x00_battery_driver);
886 }
887 
888 #else
889 
bq27x00_battery_i2c_init(void)890 static inline int bq27x00_battery_i2c_init(void) { return 0; }
bq27x00_battery_i2c_exit(void)891 static inline void bq27x00_battery_i2c_exit(void) {};
892 
893 #endif
894 
895 /* platform specific code */
896 #ifdef CONFIG_BATTERY_BQ27X00_PLATFORM
897 
bq27000_read_platform(struct bq27x00_device_info * di,u8 reg,bool single)898 static int bq27000_read_platform(struct bq27x00_device_info *di, u8 reg,
899 			bool single)
900 {
901 	struct device *dev = di->dev;
902 	struct bq27000_platform_data *pdata = dev->platform_data;
903 	unsigned int timeout = 3;
904 	int upper, lower;
905 	int temp;
906 
907 	if (!single) {
908 		/* Make sure the value has not changed in between reading the
909 		 * lower and the upper part */
910 		upper = pdata->read(dev, reg + 1);
911 		do {
912 			temp = upper;
913 			if (upper < 0)
914 				return upper;
915 
916 			lower = pdata->read(dev, reg);
917 			if (lower < 0)
918 				return lower;
919 
920 			upper = pdata->read(dev, reg + 1);
921 		} while (temp != upper && --timeout);
922 
923 		if (timeout == 0)
924 			return -EIO;
925 
926 		return (upper << 8) | lower;
927 	}
928 
929 	return pdata->read(dev, reg);
930 }
931 
bq27000_battery_probe(struct platform_device * pdev)932 static int bq27000_battery_probe(struct platform_device *pdev)
933 {
934 	struct bq27x00_device_info *di;
935 	struct bq27000_platform_data *pdata = pdev->dev.platform_data;
936 	int ret;
937 
938 	if (!pdata) {
939 		dev_err(&pdev->dev, "no platform_data supplied\n");
940 		return -EINVAL;
941 	}
942 
943 	if (!pdata->read) {
944 		dev_err(&pdev->dev, "no hdq read callback supplied\n");
945 		return -EINVAL;
946 	}
947 
948 	di = kzalloc(sizeof(*di), GFP_KERNEL);
949 	if (!di) {
950 		dev_err(&pdev->dev, "failed to allocate device info data\n");
951 		return -ENOMEM;
952 	}
953 
954 	platform_set_drvdata(pdev, di);
955 
956 	di->dev = &pdev->dev;
957 	di->chip = BQ27000;
958 
959 	di->bat.name = pdata->name ?: dev_name(&pdev->dev);
960 	di->bus.read = &bq27000_read_platform;
961 
962 	ret = bq27x00_powersupply_init(di);
963 	if (ret)
964 		goto err_free;
965 
966 	return 0;
967 
968 err_free:
969 	platform_set_drvdata(pdev, NULL);
970 	kfree(di);
971 
972 	return ret;
973 }
974 
bq27000_battery_remove(struct platform_device * pdev)975 static int bq27000_battery_remove(struct platform_device *pdev)
976 {
977 	struct bq27x00_device_info *di = platform_get_drvdata(pdev);
978 
979 	bq27x00_powersupply_unregister(di);
980 
981 	platform_set_drvdata(pdev, NULL);
982 	kfree(di);
983 
984 	return 0;
985 }
986 
987 static struct platform_driver bq27000_battery_driver = {
988 	.probe	= bq27000_battery_probe,
989 	.remove = bq27000_battery_remove,
990 	.driver = {
991 		.name = "bq27000-battery",
992 		.owner = THIS_MODULE,
993 	},
994 };
995 
bq27x00_battery_platform_init(void)996 static inline int bq27x00_battery_platform_init(void)
997 {
998 	int ret = platform_driver_register(&bq27000_battery_driver);
999 	if (ret)
1000 		printk(KERN_ERR "Unable to register BQ27000 platform driver\n");
1001 
1002 	return ret;
1003 }
1004 
bq27x00_battery_platform_exit(void)1005 static inline void bq27x00_battery_platform_exit(void)
1006 {
1007 	platform_driver_unregister(&bq27000_battery_driver);
1008 }
1009 
1010 #else
1011 
bq27x00_battery_platform_init(void)1012 static inline int bq27x00_battery_platform_init(void) { return 0; }
bq27x00_battery_platform_exit(void)1013 static inline void bq27x00_battery_platform_exit(void) {};
1014 
1015 #endif
1016 
1017 /*
1018  * Module stuff
1019  */
1020 
bq27x00_battery_init(void)1021 static int __init bq27x00_battery_init(void)
1022 {
1023 	int ret;
1024 
1025 	ret = bq27x00_battery_i2c_init();
1026 	if (ret)
1027 		return ret;
1028 
1029 	ret = bq27x00_battery_platform_init();
1030 	if (ret)
1031 		bq27x00_battery_i2c_exit();
1032 
1033 	return ret;
1034 }
1035 module_init(bq27x00_battery_init);
1036 
bq27x00_battery_exit(void)1037 static void __exit bq27x00_battery_exit(void)
1038 {
1039 	bq27x00_battery_platform_exit();
1040 	bq27x00_battery_i2c_exit();
1041 }
1042 module_exit(bq27x00_battery_exit);
1043 
1044 MODULE_AUTHOR("Rodolfo Giometti <giometti@linux.it>");
1045 MODULE_DESCRIPTION("BQ27x00 battery monitor driver");
1046 MODULE_LICENSE("GPL");
1047