GNU Linux-libre 4.4.283-gnu1
[releases.git] / drivers / power / bq27xxx_battery.c
1 /*
2  * BQ27xxx 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  * Datasheets:
20  * http://www.ti.com/product/bq27000
21  * http://www.ti.com/product/bq27200
22  * http://www.ti.com/product/bq27010
23  * http://www.ti.com/product/bq27210
24  * http://www.ti.com/product/bq27500
25  * http://www.ti.com/product/bq27510-g3
26  * http://www.ti.com/product/bq27520-g4
27  * http://www.ti.com/product/bq27530-g1
28  * http://www.ti.com/product/bq27531-g1
29  * http://www.ti.com/product/bq27541-g1
30  * http://www.ti.com/product/bq27542-g1
31  * http://www.ti.com/product/bq27546-g1
32  * http://www.ti.com/product/bq27742-g1
33  * http://www.ti.com/product/bq27545-g1
34  * http://www.ti.com/product/bq27421-g1
35  * http://www.ti.com/product/bq27425-g1
36  * http://www.ti.com/product/bq27411-g1
37  * http://www.ti.com/product/bq27621-g1
38  */
39
40 #include <linux/device.h>
41 #include <linux/module.h>
42 #include <linux/param.h>
43 #include <linux/jiffies.h>
44 #include <linux/workqueue.h>
45 #include <linux/delay.h>
46 #include <linux/platform_device.h>
47 #include <linux/power_supply.h>
48 #include <linux/idr.h>
49 #include <linux/i2c.h>
50 #include <linux/slab.h>
51 #include <linux/interrupt.h>
52 #include <asm/unaligned.h>
53
54 #include <linux/power/bq27xxx_battery.h>
55
56 #define DRIVER_VERSION          "1.2.0"
57
58 #define BQ27XXX_MANUFACTURER    "Texas Instruments"
59
60 /* BQ27XXX Flags */
61 #define BQ27XXX_FLAG_DSC        BIT(0)
62 #define BQ27XXX_FLAG_SOCF       BIT(1) /* State-of-Charge threshold final */
63 #define BQ27XXX_FLAG_SOC1       BIT(2) /* State-of-Charge threshold 1 */
64 #define BQ27XXX_FLAG_FC         BIT(9)
65 #define BQ27XXX_FLAG_OTD        BIT(14)
66 #define BQ27XXX_FLAG_OTC        BIT(15)
67 #define BQ27XXX_FLAG_UT         BIT(14)
68 #define BQ27XXX_FLAG_OT         BIT(15)
69
70 /* BQ27000 has different layout for Flags register */
71 #define BQ27000_FLAG_EDVF       BIT(0) /* Final End-of-Discharge-Voltage flag */
72 #define BQ27000_FLAG_EDV1       BIT(1) /* First End-of-Discharge-Voltage flag */
73 #define BQ27000_FLAG_CI         BIT(4) /* Capacity Inaccurate flag */
74 #define BQ27000_FLAG_FC         BIT(5)
75 #define BQ27000_FLAG_CHGS       BIT(7) /* Charge state flag */
76
77 #define BQ27XXX_RS                      (20) /* Resistor sense mOhm */
78 #define BQ27XXX_POWER_CONSTANT          (29200) /* 29.2 µV^2 * 1000 */
79 #define BQ27XXX_CURRENT_CONSTANT        (3570) /* 3.57 µV * 1000 */
80
81 struct bq27xxx_device_info;
82 struct bq27xxx_access_methods {
83         int (*read)(struct bq27xxx_device_info *di, u8 reg, bool single);
84 };
85
86 #define INVALID_REG_ADDR        0xff
87
88 /*
89  * bq27xxx_reg_index - Register names
90  *
91  * These are indexes into a device's register mapping array.
92  */
93 enum bq27xxx_reg_index {
94         BQ27XXX_REG_CTRL = 0,   /* Control */
95         BQ27XXX_REG_TEMP,       /* Temperature */
96         BQ27XXX_REG_INT_TEMP,   /* Internal Temperature */
97         BQ27XXX_REG_VOLT,       /* Voltage */
98         BQ27XXX_REG_AI,         /* Average Current */
99         BQ27XXX_REG_FLAGS,      /* Flags */
100         BQ27XXX_REG_TTE,        /* Time-to-Empty */
101         BQ27XXX_REG_TTF,        /* Time-to-Full */
102         BQ27XXX_REG_TTES,       /* Time-to-Empty Standby */
103         BQ27XXX_REG_TTECP,      /* Time-to-Empty at Constant Power */
104         BQ27XXX_REG_NAC,        /* Nominal Available Capacity */
105         BQ27XXX_REG_FCC,        /* Full Charge Capacity */
106         BQ27XXX_REG_CYCT,       /* Cycle Count */
107         BQ27XXX_REG_AE,         /* Available Energy */
108         BQ27XXX_REG_SOC,        /* State-of-Charge */
109         BQ27XXX_REG_DCAP,       /* Design Capacity */
110         BQ27XXX_REG_AP,         /* Average Power */
111 };
112
113 struct bq27xxx_reg_cache {
114         int temperature;
115         int time_to_empty;
116         int time_to_empty_avg;
117         int time_to_full;
118         int charge_full;
119         int cycle_count;
120         int capacity;
121         int energy;
122         int flags;
123         int power_avg;
124         int health;
125 };
126
127 struct bq27xxx_device_info {
128         struct device           *dev;
129         int                     id;
130         enum bq27xxx_chip       chip;
131
132         struct bq27xxx_reg_cache cache;
133         int charge_design_full;
134
135         unsigned long last_update;
136         struct delayed_work work;
137
138         struct power_supply     *bat;
139
140         struct bq27xxx_access_methods bus;
141
142         struct mutex lock;
143
144         u8 *regs;
145 };
146
147 /* Register mappings */
148 static u8 bq27000_regs[] = {
149         0x00,   /* CONTROL      */
150         0x06,   /* TEMP         */
151         INVALID_REG_ADDR,       /* INT TEMP - NA*/
152         0x08,   /* VOLT         */
153         0x14,   /* AVG CURR     */
154         0x0a,   /* FLAGS        */
155         0x16,   /* TTE          */
156         0x18,   /* TTF          */
157         0x1c,   /* TTES         */
158         0x26,   /* TTECP        */
159         0x0c,   /* NAC          */
160         0x12,   /* LMD(FCC)     */
161         0x2a,   /* CYCT         */
162         0x22,   /* AE           */
163         0x0b,   /* SOC(RSOC)    */
164         0x76,   /* DCAP(ILMD)   */
165         0x24,   /* AP           */
166 };
167
168 static u8 bq27010_regs[] = {
169         0x00,   /* CONTROL      */
170         0x06,   /* TEMP         */
171         INVALID_REG_ADDR,       /* INT TEMP - NA*/
172         0x08,   /* VOLT         */
173         0x14,   /* AVG CURR     */
174         0x0a,   /* FLAGS        */
175         0x16,   /* TTE          */
176         0x18,   /* TTF          */
177         0x1c,   /* TTES         */
178         0x26,   /* TTECP        */
179         0x0c,   /* NAC          */
180         0x12,   /* LMD(FCC)     */
181         0x2a,   /* CYCT         */
182         INVALID_REG_ADDR,       /* AE - NA      */
183         0x0b,   /* SOC(RSOC)    */
184         0x76,   /* DCAP(ILMD)   */
185         INVALID_REG_ADDR,       /* AP - NA      */
186 };
187
188 static u8 bq27500_regs[] = {
189         0x00,   /* CONTROL      */
190         0x06,   /* TEMP         */
191         0x28,   /* INT TEMP     */
192         0x08,   /* VOLT         */
193         0x14,   /* AVG CURR     */
194         0x0a,   /* FLAGS        */
195         0x16,   /* TTE          */
196         INVALID_REG_ADDR,       /* TTF - NA     */
197         0x1a,   /* TTES         */
198         INVALID_REG_ADDR,       /* TTECP - NA   */
199         0x0c,   /* NAC          */
200         0x12,   /* LMD(FCC)     */
201         0x2a,   /* CYCT         */
202         INVALID_REG_ADDR,       /* AE - NA      */
203         0x2c,   /* SOC(RSOC)    */
204         0x3c,   /* DCAP(ILMD)   */
205         INVALID_REG_ADDR,       /* AP - NA      */
206 };
207
208 static u8 bq27530_regs[] = {
209         0x00,   /* CONTROL      */
210         0x06,   /* TEMP         */
211         0x32,   /* INT TEMP     */
212         0x08,   /* VOLT         */
213         0x14,   /* AVG CURR     */
214         0x0a,   /* FLAGS        */
215         0x16,   /* TTE          */
216         INVALID_REG_ADDR,       /* TTF - NA     */
217         INVALID_REG_ADDR,       /* TTES - NA    */
218         INVALID_REG_ADDR,       /* TTECP - NA   */
219         0x0c,   /* NAC          */
220         0x12,   /* LMD(FCC)     */
221         0x2a,   /* CYCT         */
222         INVALID_REG_ADDR,       /* AE - NA      */
223         0x2c,   /* SOC(RSOC)    */
224         INVALID_REG_ADDR,       /* DCAP - NA    */
225         0x24,   /* AP           */
226 };
227
228 static u8 bq27541_regs[] = {
229         0x00,   /* CONTROL      */
230         0x06,   /* TEMP         */
231         0x28,   /* INT TEMP     */
232         0x08,   /* VOLT         */
233         0x14,   /* AVG CURR     */
234         0x0a,   /* FLAGS        */
235         0x16,   /* TTE          */
236         INVALID_REG_ADDR,       /* TTF - NA     */
237         INVALID_REG_ADDR,       /* TTES - NA    */
238         INVALID_REG_ADDR,       /* TTECP - NA   */
239         0x0c,   /* NAC          */
240         0x12,   /* LMD(FCC)     */
241         0x2a,   /* CYCT         */
242         INVALID_REG_ADDR,       /* AE - NA      */
243         0x2c,   /* SOC(RSOC)    */
244         0x3c,   /* DCAP         */
245         0x24,   /* AP           */
246 };
247
248 static u8 bq27545_regs[] = {
249         0x00,   /* CONTROL      */
250         0x06,   /* TEMP         */
251         0x28,   /* INT TEMP     */
252         0x08,   /* VOLT         */
253         0x14,   /* AVG CURR     */
254         0x0a,   /* FLAGS        */
255         0x16,   /* TTE          */
256         INVALID_REG_ADDR,       /* TTF - NA     */
257         INVALID_REG_ADDR,       /* TTES - NA    */
258         INVALID_REG_ADDR,       /* TTECP - NA   */
259         0x0c,   /* NAC          */
260         0x12,   /* LMD(FCC)     */
261         0x2a,   /* CYCT         */
262         INVALID_REG_ADDR,       /* AE - NA      */
263         0x2c,   /* SOC(RSOC)    */
264         INVALID_REG_ADDR,       /* DCAP - NA */
265         0x24,   /* AP           */
266 };
267
268 static u8 bq27421_regs[] = {
269         0x00,   /* CONTROL      */
270         0x02,   /* TEMP         */
271         0x1e,   /* INT TEMP     */
272         0x04,   /* VOLT         */
273         0x10,   /* AVG CURR     */
274         0x06,   /* FLAGS        */
275         INVALID_REG_ADDR,       /* TTE - NA     */
276         INVALID_REG_ADDR,       /* TTF - NA     */
277         INVALID_REG_ADDR,       /* TTES - NA    */
278         INVALID_REG_ADDR,       /* TTECP - NA   */
279         0x08,   /* NAC          */
280         0x0e,   /* FCC          */
281         INVALID_REG_ADDR,       /* CYCT - NA    */
282         INVALID_REG_ADDR,       /* AE - NA      */
283         0x1c,   /* SOC          */
284         0x3c,   /* DCAP         */
285         0x18,   /* AP           */
286 };
287
288 static u8 *bq27xxx_regs[] __maybe_unused = {
289         [BQ27000] = bq27000_regs,
290         [BQ27010] = bq27010_regs,
291         [BQ27500] = bq27500_regs,
292         [BQ27530] = bq27530_regs,
293         [BQ27541] = bq27541_regs,
294         [BQ27545] = bq27545_regs,
295         [BQ27421] = bq27421_regs,
296 };
297
298 static enum power_supply_property bq27000_battery_props[] = {
299         POWER_SUPPLY_PROP_STATUS,
300         POWER_SUPPLY_PROP_PRESENT,
301         POWER_SUPPLY_PROP_VOLTAGE_NOW,
302         POWER_SUPPLY_PROP_CURRENT_NOW,
303         POWER_SUPPLY_PROP_CAPACITY,
304         POWER_SUPPLY_PROP_CAPACITY_LEVEL,
305         POWER_SUPPLY_PROP_TEMP,
306         POWER_SUPPLY_PROP_TIME_TO_EMPTY_NOW,
307         POWER_SUPPLY_PROP_TIME_TO_EMPTY_AVG,
308         POWER_SUPPLY_PROP_TIME_TO_FULL_NOW,
309         POWER_SUPPLY_PROP_TECHNOLOGY,
310         POWER_SUPPLY_PROP_CHARGE_FULL,
311         POWER_SUPPLY_PROP_CHARGE_NOW,
312         POWER_SUPPLY_PROP_CHARGE_FULL_DESIGN,
313         POWER_SUPPLY_PROP_CYCLE_COUNT,
314         POWER_SUPPLY_PROP_ENERGY_NOW,
315         POWER_SUPPLY_PROP_POWER_AVG,
316         POWER_SUPPLY_PROP_HEALTH,
317         POWER_SUPPLY_PROP_MANUFACTURER,
318 };
319
320 static enum power_supply_property bq27010_battery_props[] = {
321         POWER_SUPPLY_PROP_STATUS,
322         POWER_SUPPLY_PROP_PRESENT,
323         POWER_SUPPLY_PROP_VOLTAGE_NOW,
324         POWER_SUPPLY_PROP_CURRENT_NOW,
325         POWER_SUPPLY_PROP_CAPACITY,
326         POWER_SUPPLY_PROP_CAPACITY_LEVEL,
327         POWER_SUPPLY_PROP_TEMP,
328         POWER_SUPPLY_PROP_TIME_TO_EMPTY_NOW,
329         POWER_SUPPLY_PROP_TIME_TO_EMPTY_AVG,
330         POWER_SUPPLY_PROP_TIME_TO_FULL_NOW,
331         POWER_SUPPLY_PROP_TECHNOLOGY,
332         POWER_SUPPLY_PROP_CHARGE_FULL,
333         POWER_SUPPLY_PROP_CHARGE_NOW,
334         POWER_SUPPLY_PROP_CHARGE_FULL_DESIGN,
335         POWER_SUPPLY_PROP_CYCLE_COUNT,
336         POWER_SUPPLY_PROP_HEALTH,
337         POWER_SUPPLY_PROP_MANUFACTURER,
338 };
339
340 static enum power_supply_property bq27500_battery_props[] = {
341         POWER_SUPPLY_PROP_STATUS,
342         POWER_SUPPLY_PROP_PRESENT,
343         POWER_SUPPLY_PROP_VOLTAGE_NOW,
344         POWER_SUPPLY_PROP_CURRENT_NOW,
345         POWER_SUPPLY_PROP_CAPACITY,
346         POWER_SUPPLY_PROP_CAPACITY_LEVEL,
347         POWER_SUPPLY_PROP_TEMP,
348         POWER_SUPPLY_PROP_TIME_TO_EMPTY_NOW,
349         POWER_SUPPLY_PROP_TECHNOLOGY,
350         POWER_SUPPLY_PROP_CHARGE_FULL,
351         POWER_SUPPLY_PROP_CHARGE_NOW,
352         POWER_SUPPLY_PROP_CHARGE_FULL_DESIGN,
353         POWER_SUPPLY_PROP_CYCLE_COUNT,
354         POWER_SUPPLY_PROP_HEALTH,
355         POWER_SUPPLY_PROP_MANUFACTURER,
356 };
357
358 static enum power_supply_property bq27530_battery_props[] = {
359         POWER_SUPPLY_PROP_STATUS,
360         POWER_SUPPLY_PROP_PRESENT,
361         POWER_SUPPLY_PROP_VOLTAGE_NOW,
362         POWER_SUPPLY_PROP_CURRENT_NOW,
363         POWER_SUPPLY_PROP_CAPACITY,
364         POWER_SUPPLY_PROP_CAPACITY_LEVEL,
365         POWER_SUPPLY_PROP_TEMP,
366         POWER_SUPPLY_PROP_TIME_TO_EMPTY_NOW,
367         POWER_SUPPLY_PROP_TECHNOLOGY,
368         POWER_SUPPLY_PROP_CHARGE_FULL,
369         POWER_SUPPLY_PROP_CHARGE_NOW,
370         POWER_SUPPLY_PROP_POWER_AVG,
371         POWER_SUPPLY_PROP_HEALTH,
372         POWER_SUPPLY_PROP_CYCLE_COUNT,
373         POWER_SUPPLY_PROP_MANUFACTURER,
374 };
375
376 static enum power_supply_property bq27541_battery_props[] = {
377         POWER_SUPPLY_PROP_STATUS,
378         POWER_SUPPLY_PROP_PRESENT,
379         POWER_SUPPLY_PROP_VOLTAGE_NOW,
380         POWER_SUPPLY_PROP_CURRENT_NOW,
381         POWER_SUPPLY_PROP_CAPACITY,
382         POWER_SUPPLY_PROP_CAPACITY_LEVEL,
383         POWER_SUPPLY_PROP_TEMP,
384         POWER_SUPPLY_PROP_TIME_TO_EMPTY_NOW,
385         POWER_SUPPLY_PROP_TECHNOLOGY,
386         POWER_SUPPLY_PROP_CHARGE_FULL,
387         POWER_SUPPLY_PROP_CHARGE_NOW,
388         POWER_SUPPLY_PROP_CHARGE_FULL_DESIGN,
389         POWER_SUPPLY_PROP_CYCLE_COUNT,
390         POWER_SUPPLY_PROP_POWER_AVG,
391         POWER_SUPPLY_PROP_HEALTH,
392         POWER_SUPPLY_PROP_MANUFACTURER,
393 };
394
395 static enum power_supply_property bq27545_battery_props[] = {
396         POWER_SUPPLY_PROP_STATUS,
397         POWER_SUPPLY_PROP_PRESENT,
398         POWER_SUPPLY_PROP_VOLTAGE_NOW,
399         POWER_SUPPLY_PROP_CURRENT_NOW,
400         POWER_SUPPLY_PROP_CAPACITY,
401         POWER_SUPPLY_PROP_CAPACITY_LEVEL,
402         POWER_SUPPLY_PROP_TEMP,
403         POWER_SUPPLY_PROP_TIME_TO_EMPTY_NOW,
404         POWER_SUPPLY_PROP_TECHNOLOGY,
405         POWER_SUPPLY_PROP_CHARGE_FULL,
406         POWER_SUPPLY_PROP_CHARGE_NOW,
407         POWER_SUPPLY_PROP_HEALTH,
408         POWER_SUPPLY_PROP_CYCLE_COUNT,
409         POWER_SUPPLY_PROP_POWER_AVG,
410         POWER_SUPPLY_PROP_MANUFACTURER,
411 };
412
413 static enum power_supply_property bq27421_battery_props[] = {
414         POWER_SUPPLY_PROP_STATUS,
415         POWER_SUPPLY_PROP_PRESENT,
416         POWER_SUPPLY_PROP_VOLTAGE_NOW,
417         POWER_SUPPLY_PROP_CURRENT_NOW,
418         POWER_SUPPLY_PROP_CAPACITY,
419         POWER_SUPPLY_PROP_CAPACITY_LEVEL,
420         POWER_SUPPLY_PROP_TEMP,
421         POWER_SUPPLY_PROP_TECHNOLOGY,
422         POWER_SUPPLY_PROP_CHARGE_FULL,
423         POWER_SUPPLY_PROP_CHARGE_NOW,
424         POWER_SUPPLY_PROP_CHARGE_FULL_DESIGN,
425         POWER_SUPPLY_PROP_MANUFACTURER,
426 };
427
428 #define BQ27XXX_PROP(_id, _prop)                \
429         [_id] = {                               \
430                 .props = _prop,                 \
431                 .size = ARRAY_SIZE(_prop),      \
432         }
433
434 static struct {
435         enum power_supply_property *props;
436         size_t size;
437 } bq27xxx_battery_props[] = {
438         BQ27XXX_PROP(BQ27000, bq27000_battery_props),
439         BQ27XXX_PROP(BQ27010, bq27010_battery_props),
440         BQ27XXX_PROP(BQ27500, bq27500_battery_props),
441         BQ27XXX_PROP(BQ27530, bq27530_battery_props),
442         BQ27XXX_PROP(BQ27541, bq27541_battery_props),
443         BQ27XXX_PROP(BQ27545, bq27545_battery_props),
444         BQ27XXX_PROP(BQ27421, bq27421_battery_props),
445 };
446
447 static unsigned int poll_interval = 360;
448 module_param(poll_interval, uint, 0644);
449 MODULE_PARM_DESC(poll_interval,
450                  "battery poll interval in seconds - 0 disables polling");
451
452 /*
453  * Common code for BQ27xxx devices
454  */
455
456 static inline int bq27xxx_read(struct bq27xxx_device_info *di, int reg_index,
457                                bool single)
458 {
459         /* Reports EINVAL for invalid/missing registers */
460         if (!di || di->regs[reg_index] == INVALID_REG_ADDR)
461                 return -EINVAL;
462
463         return di->bus.read(di, di->regs[reg_index], single);
464 }
465
466 /*
467  * Return the battery State-of-Charge
468  * Or < 0 if something fails.
469  */
470 static int bq27xxx_battery_read_soc(struct bq27xxx_device_info *di)
471 {
472         int soc;
473
474         if (di->chip == BQ27000 || di->chip == BQ27010)
475                 soc = bq27xxx_read(di, BQ27XXX_REG_SOC, true);
476         else
477                 soc = bq27xxx_read(di, BQ27XXX_REG_SOC, false);
478
479         if (soc < 0)
480                 dev_dbg(di->dev, "error reading State-of-Charge\n");
481
482         return soc;
483 }
484
485 /*
486  * Return a battery charge value in µAh
487  * Or < 0 if something fails.
488  */
489 static int bq27xxx_battery_read_charge(struct bq27xxx_device_info *di, u8 reg)
490 {
491         int charge;
492
493         charge = bq27xxx_read(di, reg, false);
494         if (charge < 0) {
495                 dev_dbg(di->dev, "error reading charge register %02x: %d\n",
496                         reg, charge);
497                 return charge;
498         }
499
500         if (di->chip == BQ27000 || di->chip == BQ27010)
501                 charge *= BQ27XXX_CURRENT_CONSTANT / BQ27XXX_RS;
502         else
503                 charge *= 1000;
504
505         return charge;
506 }
507
508 /*
509  * Return the battery Nominal available capacity in µAh
510  * Or < 0 if something fails.
511  */
512 static inline int bq27xxx_battery_read_nac(struct bq27xxx_device_info *di)
513 {
514         int flags;
515
516         if (di->chip == BQ27000 || di->chip == BQ27010) {
517                 flags = bq27xxx_read(di, BQ27XXX_REG_FLAGS, true);
518                 if (flags >= 0 && (flags & BQ27000_FLAG_CI))
519                         return -ENODATA;
520         }
521
522         return bq27xxx_battery_read_charge(di, BQ27XXX_REG_NAC);
523 }
524
525 /*
526  * Return the battery Full Charge Capacity in µAh
527  * Or < 0 if something fails.
528  */
529 static inline int bq27xxx_battery_read_fcc(struct bq27xxx_device_info *di)
530 {
531         return bq27xxx_battery_read_charge(di, BQ27XXX_REG_FCC);
532 }
533
534 /*
535  * Return the Design Capacity in µAh
536  * Or < 0 if something fails.
537  */
538 static int bq27xxx_battery_read_dcap(struct bq27xxx_device_info *di)
539 {
540         int dcap;
541
542         if (di->chip == BQ27000 || di->chip == BQ27010)
543                 dcap = bq27xxx_read(di, BQ27XXX_REG_DCAP, true);
544         else
545                 dcap = bq27xxx_read(di, BQ27XXX_REG_DCAP, false);
546
547         if (dcap < 0) {
548                 dev_dbg(di->dev, "error reading initial last measured discharge\n");
549                 return dcap;
550         }
551
552         if (di->chip == BQ27000 || di->chip == BQ27010)
553                 dcap = (dcap << 8) * BQ27XXX_CURRENT_CONSTANT / BQ27XXX_RS;
554         else
555                 dcap *= 1000;
556
557         return dcap;
558 }
559
560 /*
561  * Return the battery Available energy in µWh
562  * Or < 0 if something fails.
563  */
564 static int bq27xxx_battery_read_energy(struct bq27xxx_device_info *di)
565 {
566         int ae;
567
568         ae = bq27xxx_read(di, BQ27XXX_REG_AE, false);
569         if (ae < 0) {
570                 dev_dbg(di->dev, "error reading available energy\n");
571                 return ae;
572         }
573
574         if (di->chip == BQ27000 || di->chip == BQ27010)
575                 ae *= BQ27XXX_POWER_CONSTANT / BQ27XXX_RS;
576         else
577                 ae *= 1000;
578
579         return ae;
580 }
581
582 /*
583  * Return the battery temperature in tenths of degree Kelvin
584  * Or < 0 if something fails.
585  */
586 static int bq27xxx_battery_read_temperature(struct bq27xxx_device_info *di)
587 {
588         int temp;
589
590         temp = bq27xxx_read(di, BQ27XXX_REG_TEMP, false);
591         if (temp < 0) {
592                 dev_err(di->dev, "error reading temperature\n");
593                 return temp;
594         }
595
596         if (di->chip == BQ27000 || di->chip == BQ27010)
597                 temp = 5 * temp / 2;
598
599         return temp;
600 }
601
602 /*
603  * Return the battery Cycle count total
604  * Or < 0 if something fails.
605  */
606 static int bq27xxx_battery_read_cyct(struct bq27xxx_device_info *di)
607 {
608         int cyct;
609
610         cyct = bq27xxx_read(di, BQ27XXX_REG_CYCT, false);
611         if (cyct < 0)
612                 dev_err(di->dev, "error reading cycle count total\n");
613
614         return cyct;
615 }
616
617 /*
618  * Read a time register.
619  * Return < 0 if something fails.
620  */
621 static int bq27xxx_battery_read_time(struct bq27xxx_device_info *di, u8 reg)
622 {
623         int tval;
624
625         tval = bq27xxx_read(di, reg, false);
626         if (tval < 0) {
627                 dev_dbg(di->dev, "error reading time register %02x: %d\n",
628                         reg, tval);
629                 return tval;
630         }
631
632         if (tval == 65535)
633                 return -ENODATA;
634
635         return tval * 60;
636 }
637
638 /*
639  * Read an average power register.
640  * Return < 0 if something fails.
641  */
642 static int bq27xxx_battery_read_pwr_avg(struct bq27xxx_device_info *di)
643 {
644         int tval;
645
646         tval = bq27xxx_read(di, BQ27XXX_REG_AP, false);
647         if (tval < 0) {
648                 dev_err(di->dev, "error reading average power register  %02x: %d\n",
649                         BQ27XXX_REG_AP, tval);
650                 return tval;
651         }
652
653         if (di->chip == BQ27000 || di->chip == BQ27010)
654                 return (tval * BQ27XXX_POWER_CONSTANT) / BQ27XXX_RS;
655         else
656                 return tval;
657 }
658
659 /*
660  * Returns true if a battery over temperature condition is detected
661  */
662 static bool bq27xxx_battery_overtemp(struct bq27xxx_device_info *di, u16 flags)
663 {
664         if (di->chip == BQ27500 || di->chip == BQ27541 || di->chip == BQ27545)
665                 return flags & (BQ27XXX_FLAG_OTC | BQ27XXX_FLAG_OTD);
666         if (di->chip == BQ27530 || di->chip == BQ27421)
667                 return flags & BQ27XXX_FLAG_OT;
668
669         return false;
670 }
671
672 /*
673  * Returns true if a battery under temperature condition is detected
674  */
675 static bool bq27xxx_battery_undertemp(struct bq27xxx_device_info *di, u16 flags)
676 {
677         if (di->chip == BQ27530 || di->chip == BQ27421)
678                 return flags & BQ27XXX_FLAG_UT;
679
680         return false;
681 }
682
683 /*
684  * Returns true if a low state of charge condition is detected
685  */
686 static bool bq27xxx_battery_dead(struct bq27xxx_device_info *di, u16 flags)
687 {
688         if (di->chip == BQ27000 || di->chip == BQ27010)
689                 return flags & (BQ27000_FLAG_EDV1 | BQ27000_FLAG_EDVF);
690         else
691                 return flags & (BQ27XXX_FLAG_SOC1 | BQ27XXX_FLAG_SOCF);
692 }
693
694 /*
695  * Read flag register.
696  * Return < 0 if something fails.
697  */
698 static int bq27xxx_battery_read_health(struct bq27xxx_device_info *di)
699 {
700         int flags;
701
702         flags = bq27xxx_read(di, BQ27XXX_REG_FLAGS, false);
703         if (flags < 0) {
704                 dev_err(di->dev, "error reading flag register:%d\n", flags);
705                 return flags;
706         }
707
708         /* Unlikely but important to return first */
709         if (unlikely(bq27xxx_battery_overtemp(di, flags)))
710                 return POWER_SUPPLY_HEALTH_OVERHEAT;
711         if (unlikely(bq27xxx_battery_undertemp(di, flags)))
712                 return POWER_SUPPLY_HEALTH_COLD;
713         if (unlikely(bq27xxx_battery_dead(di, flags)))
714                 return POWER_SUPPLY_HEALTH_DEAD;
715
716         return POWER_SUPPLY_HEALTH_GOOD;
717 }
718
719 static void bq27xxx_battery_update(struct bq27xxx_device_info *di)
720 {
721         struct bq27xxx_reg_cache cache = {0, };
722         bool has_ci_flag = di->chip == BQ27000 || di->chip == BQ27010;
723         bool has_singe_flag = di->chip == BQ27000 || di->chip == BQ27010;
724
725         cache.flags = bq27xxx_read(di, BQ27XXX_REG_FLAGS, has_singe_flag);
726         if ((cache.flags & 0xff) == 0xff)
727                 cache.flags = -1; /* read error */
728         if (cache.flags >= 0) {
729                 cache.temperature = bq27xxx_battery_read_temperature(di);
730                 if (has_ci_flag && (cache.flags & BQ27000_FLAG_CI)) {
731                         dev_info(di->dev, "battery is not calibrated! ignoring capacity values\n");
732                         cache.capacity = -ENODATA;
733                         cache.energy = -ENODATA;
734                         cache.time_to_empty = -ENODATA;
735                         cache.time_to_empty_avg = -ENODATA;
736                         cache.time_to_full = -ENODATA;
737                         cache.charge_full = -ENODATA;
738                         cache.health = -ENODATA;
739                 } else {
740                         if (di->regs[BQ27XXX_REG_TTE] != INVALID_REG_ADDR)
741                                 cache.time_to_empty = bq27xxx_battery_read_time(di, BQ27XXX_REG_TTE);
742                         if (di->regs[BQ27XXX_REG_TTECP] != INVALID_REG_ADDR)
743                                 cache.time_to_empty_avg = bq27xxx_battery_read_time(di, BQ27XXX_REG_TTECP);
744                         if (di->regs[BQ27XXX_REG_TTF] != INVALID_REG_ADDR)
745                                 cache.time_to_full = bq27xxx_battery_read_time(di, BQ27XXX_REG_TTF);
746                         cache.charge_full = bq27xxx_battery_read_fcc(di);
747                         cache.capacity = bq27xxx_battery_read_soc(di);
748                         if (di->regs[BQ27XXX_REG_AE] != INVALID_REG_ADDR)
749                                 cache.energy = bq27xxx_battery_read_energy(di);
750                         cache.health = bq27xxx_battery_read_health(di);
751                 }
752                 if (di->regs[BQ27XXX_REG_CYCT] != INVALID_REG_ADDR)
753                         cache.cycle_count = bq27xxx_battery_read_cyct(di);
754                 if (di->regs[BQ27XXX_REG_AP] != INVALID_REG_ADDR)
755                         cache.power_avg = bq27xxx_battery_read_pwr_avg(di);
756
757                 /* We only have to read charge design full once */
758                 if (di->charge_design_full <= 0)
759                         di->charge_design_full = bq27xxx_battery_read_dcap(di);
760         }
761
762         if (di->cache.capacity != cache.capacity)
763                 power_supply_changed(di->bat);
764
765         if (memcmp(&di->cache, &cache, sizeof(cache)) != 0)
766                 di->cache = cache;
767
768         di->last_update = jiffies;
769 }
770
771 static void bq27xxx_battery_poll(struct work_struct *work)
772 {
773         struct bq27xxx_device_info *di =
774                         container_of(work, struct bq27xxx_device_info,
775                                      work.work);
776
777         bq27xxx_battery_update(di);
778
779         if (poll_interval > 0) {
780                 /* The timer does not have to be accurate. */
781                 set_timer_slack(&di->work.timer, poll_interval * HZ / 4);
782                 schedule_delayed_work(&di->work, poll_interval * HZ);
783         }
784 }
785
786 /*
787  * Return the battery average current in µA
788  * Note that current can be negative signed as well
789  * Or 0 if something fails.
790  */
791 static int bq27xxx_battery_current(struct bq27xxx_device_info *di,
792                                    union power_supply_propval *val)
793 {
794         int curr;
795         int flags;
796
797         curr = bq27xxx_read(di, BQ27XXX_REG_AI, false);
798         if (curr < 0) {
799                 dev_err(di->dev, "error reading current\n");
800                 return curr;
801         }
802
803         if (di->chip == BQ27000 || di->chip == BQ27010) {
804                 flags = bq27xxx_read(di, BQ27XXX_REG_FLAGS, false);
805                 if (flags & BQ27000_FLAG_CHGS) {
806                         dev_dbg(di->dev, "negative current!\n");
807                         curr = -curr;
808                 }
809
810                 val->intval = curr * BQ27XXX_CURRENT_CONSTANT / BQ27XXX_RS;
811         } else {
812                 /* Other gauges return signed value */
813                 val->intval = (int)((s16)curr) * 1000;
814         }
815
816         return 0;
817 }
818
819 static int bq27xxx_battery_status(struct bq27xxx_device_info *di,
820                                   union power_supply_propval *val)
821 {
822         int status;
823
824         if (di->chip == BQ27000 || di->chip == BQ27010) {
825                 if (di->cache.flags & BQ27000_FLAG_FC)
826                         status = POWER_SUPPLY_STATUS_FULL;
827                 else if (di->cache.flags & BQ27000_FLAG_CHGS)
828                         status = POWER_SUPPLY_STATUS_CHARGING;
829                 else if (power_supply_am_i_supplied(di->bat))
830                         status = POWER_SUPPLY_STATUS_NOT_CHARGING;
831                 else
832                         status = POWER_SUPPLY_STATUS_DISCHARGING;
833         } else {
834                 if (di->cache.flags & BQ27XXX_FLAG_FC)
835                         status = POWER_SUPPLY_STATUS_FULL;
836                 else if (di->cache.flags & BQ27XXX_FLAG_DSC)
837                         status = POWER_SUPPLY_STATUS_DISCHARGING;
838                 else
839                         status = POWER_SUPPLY_STATUS_CHARGING;
840         }
841
842         val->intval = status;
843
844         return 0;
845 }
846
847 static int bq27xxx_battery_capacity_level(struct bq27xxx_device_info *di,
848                                           union power_supply_propval *val)
849 {
850         int level;
851
852         if (di->chip == BQ27000 || di->chip == BQ27010) {
853                 if (di->cache.flags & BQ27000_FLAG_FC)
854                         level = POWER_SUPPLY_CAPACITY_LEVEL_FULL;
855                 else if (di->cache.flags & BQ27000_FLAG_EDV1)
856                         level = POWER_SUPPLY_CAPACITY_LEVEL_LOW;
857                 else if (di->cache.flags & BQ27000_FLAG_EDVF)
858                         level = POWER_SUPPLY_CAPACITY_LEVEL_CRITICAL;
859                 else
860                         level = POWER_SUPPLY_CAPACITY_LEVEL_NORMAL;
861         } else {
862                 if (di->cache.flags & BQ27XXX_FLAG_FC)
863                         level = POWER_SUPPLY_CAPACITY_LEVEL_FULL;
864                 else if (di->cache.flags & BQ27XXX_FLAG_SOC1)
865                         level = POWER_SUPPLY_CAPACITY_LEVEL_LOW;
866                 else if (di->cache.flags & BQ27XXX_FLAG_SOCF)
867                         level = POWER_SUPPLY_CAPACITY_LEVEL_CRITICAL;
868                 else
869                         level = POWER_SUPPLY_CAPACITY_LEVEL_NORMAL;
870         }
871
872         val->intval = level;
873
874         return 0;
875 }
876
877 /*
878  * Return the battery Voltage in millivolts
879  * Or < 0 if something fails.
880  */
881 static int bq27xxx_battery_voltage(struct bq27xxx_device_info *di,
882                                    union power_supply_propval *val)
883 {
884         int volt;
885
886         volt = bq27xxx_read(di, BQ27XXX_REG_VOLT, false);
887         if (volt < 0) {
888                 dev_err(di->dev, "error reading voltage\n");
889                 return volt;
890         }
891
892         val->intval = volt * 1000;
893
894         return 0;
895 }
896
897 static int bq27xxx_simple_value(int value,
898                                 union power_supply_propval *val)
899 {
900         if (value < 0)
901                 return value;
902
903         val->intval = value;
904
905         return 0;
906 }
907
908 static int bq27xxx_battery_get_property(struct power_supply *psy,
909                                         enum power_supply_property psp,
910                                         union power_supply_propval *val)
911 {
912         int ret = 0;
913         struct bq27xxx_device_info *di = power_supply_get_drvdata(psy);
914
915         mutex_lock(&di->lock);
916         if (time_is_before_jiffies(di->last_update + 5 * HZ)) {
917                 cancel_delayed_work_sync(&di->work);
918                 bq27xxx_battery_poll(&di->work.work);
919         }
920         mutex_unlock(&di->lock);
921
922         if (psp != POWER_SUPPLY_PROP_PRESENT && di->cache.flags < 0)
923                 return -ENODEV;
924
925         switch (psp) {
926         case POWER_SUPPLY_PROP_STATUS:
927                 ret = bq27xxx_battery_status(di, val);
928                 break;
929         case POWER_SUPPLY_PROP_VOLTAGE_NOW:
930                 ret = bq27xxx_battery_voltage(di, val);
931                 break;
932         case POWER_SUPPLY_PROP_PRESENT:
933                 val->intval = di->cache.flags < 0 ? 0 : 1;
934                 break;
935         case POWER_SUPPLY_PROP_CURRENT_NOW:
936                 ret = bq27xxx_battery_current(di, val);
937                 break;
938         case POWER_SUPPLY_PROP_CAPACITY:
939                 ret = bq27xxx_simple_value(di->cache.capacity, val);
940                 break;
941         case POWER_SUPPLY_PROP_CAPACITY_LEVEL:
942                 ret = bq27xxx_battery_capacity_level(di, val);
943                 break;
944         case POWER_SUPPLY_PROP_TEMP:
945                 ret = bq27xxx_simple_value(di->cache.temperature, val);
946                 if (ret == 0)
947                         val->intval -= 2731; /* convert decidegree k to c */
948                 break;
949         case POWER_SUPPLY_PROP_TIME_TO_EMPTY_NOW:
950                 ret = bq27xxx_simple_value(di->cache.time_to_empty, val);
951                 break;
952         case POWER_SUPPLY_PROP_TIME_TO_EMPTY_AVG:
953                 ret = bq27xxx_simple_value(di->cache.time_to_empty_avg, val);
954                 break;
955         case POWER_SUPPLY_PROP_TIME_TO_FULL_NOW:
956                 ret = bq27xxx_simple_value(di->cache.time_to_full, val);
957                 break;
958         case POWER_SUPPLY_PROP_TECHNOLOGY:
959                 val->intval = POWER_SUPPLY_TECHNOLOGY_LION;
960                 break;
961         case POWER_SUPPLY_PROP_CHARGE_NOW:
962                 ret = bq27xxx_simple_value(bq27xxx_battery_read_nac(di), val);
963                 break;
964         case POWER_SUPPLY_PROP_CHARGE_FULL:
965                 ret = bq27xxx_simple_value(di->cache.charge_full, val);
966                 break;
967         case POWER_SUPPLY_PROP_CHARGE_FULL_DESIGN:
968                 ret = bq27xxx_simple_value(di->charge_design_full, val);
969                 break;
970         case POWER_SUPPLY_PROP_CYCLE_COUNT:
971                 ret = bq27xxx_simple_value(di->cache.cycle_count, val);
972                 break;
973         case POWER_SUPPLY_PROP_ENERGY_NOW:
974                 ret = bq27xxx_simple_value(di->cache.energy, val);
975                 break;
976         case POWER_SUPPLY_PROP_POWER_AVG:
977                 ret = bq27xxx_simple_value(di->cache.power_avg, val);
978                 break;
979         case POWER_SUPPLY_PROP_HEALTH:
980                 ret = bq27xxx_simple_value(di->cache.health, val);
981                 break;
982         case POWER_SUPPLY_PROP_MANUFACTURER:
983                 val->strval = BQ27XXX_MANUFACTURER;
984                 break;
985         default:
986                 return -EINVAL;
987         }
988
989         return ret;
990 }
991
992 static void bq27xxx_external_power_changed(struct power_supply *psy)
993 {
994         struct bq27xxx_device_info *di = power_supply_get_drvdata(psy);
995
996         cancel_delayed_work_sync(&di->work);
997         schedule_delayed_work(&di->work, 0);
998 }
999
1000 static int __maybe_unused bq27xxx_powersupply_init(struct bq27xxx_device_info *di,
1001                                     const char *name)
1002 {
1003         int ret;
1004         struct power_supply_desc *psy_desc;
1005         struct power_supply_config psy_cfg = { .drv_data = di, };
1006
1007         psy_desc = devm_kzalloc(di->dev, sizeof(*psy_desc), GFP_KERNEL);
1008         if (!psy_desc)
1009                 return -ENOMEM;
1010
1011         psy_desc->name = name;
1012         psy_desc->type = POWER_SUPPLY_TYPE_BATTERY;
1013         psy_desc->properties = bq27xxx_battery_props[di->chip].props;
1014         psy_desc->num_properties = bq27xxx_battery_props[di->chip].size;
1015         psy_desc->get_property = bq27xxx_battery_get_property;
1016         psy_desc->external_power_changed = bq27xxx_external_power_changed;
1017
1018         INIT_DELAYED_WORK(&di->work, bq27xxx_battery_poll);
1019         mutex_init(&di->lock);
1020
1021         di->bat = power_supply_register_no_ws(di->dev, psy_desc, &psy_cfg);
1022         if (IS_ERR(di->bat)) {
1023                 ret = PTR_ERR(di->bat);
1024                 dev_err(di->dev, "failed to register battery: %d\n", ret);
1025                 return ret;
1026         }
1027
1028         dev_info(di->dev, "support ver. %s enabled\n", DRIVER_VERSION);
1029
1030         bq27xxx_battery_update(di);
1031
1032         return 0;
1033 }
1034
1035 static void __maybe_unused bq27xxx_powersupply_unregister(struct bq27xxx_device_info *di)
1036 {
1037         /*
1038          * power_supply_unregister call bq27xxx_battery_get_property which
1039          * call bq27xxx_battery_poll.
1040          * Make sure that bq27xxx_battery_poll will not call
1041          * schedule_delayed_work again after unregister (which cause OOPS).
1042          */
1043         poll_interval = 0;
1044
1045         cancel_delayed_work_sync(&di->work);
1046
1047         power_supply_unregister(di->bat);
1048
1049         mutex_destroy(&di->lock);
1050 }
1051
1052 /* i2c specific code */
1053 #ifdef CONFIG_BATTERY_BQ27XXX_I2C
1054
1055 /* If the system has several batteries we need a different name for each
1056  * of them...
1057  */
1058 static DEFINE_IDR(battery_id);
1059 static DEFINE_MUTEX(battery_mutex);
1060
1061 static irqreturn_t bq27xxx_battery_irq_handler_thread(int irq, void *data)
1062 {
1063         struct bq27xxx_device_info *di = data;
1064
1065         bq27xxx_battery_update(di);
1066
1067         return IRQ_HANDLED;
1068 }
1069
1070 static int bq27xxx_battery_i2c_read(struct bq27xxx_device_info *di, u8 reg,
1071                                     bool single)
1072 {
1073         struct i2c_client *client = to_i2c_client(di->dev);
1074         struct i2c_msg msg[2];
1075         unsigned char data[2];
1076         int ret;
1077
1078         if (!client->adapter)
1079                 return -ENODEV;
1080
1081         msg[0].addr = client->addr;
1082         msg[0].flags = 0;
1083         msg[0].buf = &reg;
1084         msg[0].len = sizeof(reg);
1085         msg[1].addr = client->addr;
1086         msg[1].flags = I2C_M_RD;
1087         msg[1].buf = data;
1088         if (single)
1089                 msg[1].len = 1;
1090         else
1091                 msg[1].len = 2;
1092
1093         ret = i2c_transfer(client->adapter, msg, ARRAY_SIZE(msg));
1094         if (ret < 0)
1095                 return ret;
1096
1097         if (!single)
1098                 ret = get_unaligned_le16(data);
1099         else
1100                 ret = data[0];
1101
1102         return ret;
1103 }
1104
1105 static int bq27xxx_battery_i2c_probe(struct i2c_client *client,
1106                                      const struct i2c_device_id *id)
1107 {
1108         char *name;
1109         struct bq27xxx_device_info *di;
1110         int num;
1111         int retval = 0;
1112
1113         /* Get new ID for the new battery device */
1114         mutex_lock(&battery_mutex);
1115         num = idr_alloc(&battery_id, client, 0, 0, GFP_KERNEL);
1116         mutex_unlock(&battery_mutex);
1117         if (num < 0)
1118                 return num;
1119
1120         name = devm_kasprintf(&client->dev, GFP_KERNEL, "%s-%d", id->name, num);
1121         if (!name) {
1122                 retval = -ENOMEM;
1123                 goto batt_failed;
1124         }
1125
1126         di = devm_kzalloc(&client->dev, sizeof(*di), GFP_KERNEL);
1127         if (!di) {
1128                 retval = -ENOMEM;
1129                 goto batt_failed;
1130         }
1131
1132         di->id = num;
1133         di->dev = &client->dev;
1134         di->chip = id->driver_data;
1135         di->bus.read = &bq27xxx_battery_i2c_read;
1136         di->regs = bq27xxx_regs[di->chip];
1137
1138         retval = bq27xxx_powersupply_init(di, name);
1139         if (retval)
1140                 goto batt_failed;
1141
1142         /* Schedule a polling after about 1 min */
1143         schedule_delayed_work(&di->work, 60 * HZ);
1144
1145         i2c_set_clientdata(client, di);
1146
1147         if (client->irq) {
1148                 retval = devm_request_threaded_irq(&client->dev, client->irq,
1149                                 NULL, bq27xxx_battery_irq_handler_thread,
1150                                 IRQF_ONESHOT,
1151                                 name, di);
1152                 if (retval) {
1153                         dev_err(&client->dev,
1154                                 "Unable to register IRQ %d error %d\n",
1155                                 client->irq, retval);
1156                         return retval;
1157                 }
1158         }
1159
1160         return 0;
1161
1162 batt_failed:
1163         mutex_lock(&battery_mutex);
1164         idr_remove(&battery_id, num);
1165         mutex_unlock(&battery_mutex);
1166
1167         return retval;
1168 }
1169
1170 static int bq27xxx_battery_i2c_remove(struct i2c_client *client)
1171 {
1172         struct bq27xxx_device_info *di = i2c_get_clientdata(client);
1173
1174         bq27xxx_powersupply_unregister(di);
1175
1176         mutex_lock(&battery_mutex);
1177         idr_remove(&battery_id, di->id);
1178         mutex_unlock(&battery_mutex);
1179
1180         return 0;
1181 }
1182
1183 static const struct i2c_device_id bq27xxx_id[] = {
1184         { "bq27200", BQ27000 },
1185         { "bq27210", BQ27010 },
1186         { "bq27500", BQ27500 },
1187         { "bq27510", BQ27500 },
1188         { "bq27520", BQ27500 },
1189         { "bq27530", BQ27530 },
1190         { "bq27531", BQ27530 },
1191         { "bq27541", BQ27541 },
1192         { "bq27542", BQ27541 },
1193         { "bq27546", BQ27541 },
1194         { "bq27742", BQ27541 },
1195         { "bq27545", BQ27545 },
1196         { "bq27421", BQ27421 },
1197         { "bq27425", BQ27421 },
1198         { "bq27441", BQ27421 },
1199         { "bq27621", BQ27421 },
1200         {},
1201 };
1202 MODULE_DEVICE_TABLE(i2c, bq27xxx_id);
1203
1204 static struct i2c_driver bq27xxx_battery_i2c_driver = {
1205         .driver = {
1206                 .name = "bq27xxx-battery",
1207         },
1208         .probe = bq27xxx_battery_i2c_probe,
1209         .remove = bq27xxx_battery_i2c_remove,
1210         .id_table = bq27xxx_id,
1211 };
1212
1213 static inline int bq27xxx_battery_i2c_init(void)
1214 {
1215         int ret = i2c_add_driver(&bq27xxx_battery_i2c_driver);
1216
1217         if (ret)
1218                 pr_err("Unable to register BQ27xxx i2c driver\n");
1219
1220         return ret;
1221 }
1222
1223 static inline void bq27xxx_battery_i2c_exit(void)
1224 {
1225         i2c_del_driver(&bq27xxx_battery_i2c_driver);
1226 }
1227
1228 #else
1229
1230 static inline int bq27xxx_battery_i2c_init(void) { return 0; }
1231 static inline void bq27xxx_battery_i2c_exit(void) {};
1232
1233 #endif
1234
1235 /* platform specific code */
1236 #ifdef CONFIG_BATTERY_BQ27XXX_PLATFORM
1237
1238 static int bq27xxx_battery_platform_read(struct bq27xxx_device_info *di, u8 reg,
1239                                          bool single)
1240 {
1241         struct device *dev = di->dev;
1242         struct bq27xxx_platform_data *pdata = dev->platform_data;
1243         unsigned int timeout = 3;
1244         int upper, lower;
1245         int temp;
1246
1247         if (!single) {
1248                 /* Make sure the value has not changed in between reading the
1249                  * lower and the upper part */
1250                 upper = pdata->read(dev, reg + 1);
1251                 do {
1252                         temp = upper;
1253                         if (upper < 0)
1254                                 return upper;
1255
1256                         lower = pdata->read(dev, reg);
1257                         if (lower < 0)
1258                                 return lower;
1259
1260                         upper = pdata->read(dev, reg + 1);
1261                 } while (temp != upper && --timeout);
1262
1263                 if (timeout == 0)
1264                         return -EIO;
1265
1266                 return (upper << 8) | lower;
1267         }
1268
1269         return pdata->read(dev, reg);
1270 }
1271
1272 static int bq27xxx_battery_platform_probe(struct platform_device *pdev)
1273 {
1274         struct bq27xxx_device_info *di;
1275         struct bq27xxx_platform_data *pdata = pdev->dev.platform_data;
1276         const char *name;
1277
1278         if (!pdata) {
1279                 dev_err(&pdev->dev, "no platform_data supplied\n");
1280                 return -EINVAL;
1281         }
1282
1283         if (!pdata->read) {
1284                 dev_err(&pdev->dev, "no hdq read callback supplied\n");
1285                 return -EINVAL;
1286         }
1287
1288         if (!pdata->chip) {
1289                 dev_err(&pdev->dev, "no device supplied\n");
1290                 return -EINVAL;
1291         }
1292
1293         di = devm_kzalloc(&pdev->dev, sizeof(*di), GFP_KERNEL);
1294         if (!di)
1295                 return -ENOMEM;
1296
1297         platform_set_drvdata(pdev, di);
1298
1299         di->dev = &pdev->dev;
1300         di->chip = pdata->chip;
1301         di->regs = bq27xxx_regs[di->chip];
1302
1303         name = pdata->name ?: dev_name(&pdev->dev);
1304         di->bus.read = &bq27xxx_battery_platform_read;
1305
1306         return bq27xxx_powersupply_init(di, name);
1307 }
1308
1309 static int bq27xxx_battery_platform_remove(struct platform_device *pdev)
1310 {
1311         struct bq27xxx_device_info *di = platform_get_drvdata(pdev);
1312
1313         bq27xxx_powersupply_unregister(di);
1314
1315         return 0;
1316 }
1317
1318 static struct platform_driver bq27xxx_battery_platform_driver = {
1319         .probe  = bq27xxx_battery_platform_probe,
1320         .remove = bq27xxx_battery_platform_remove,
1321         .driver = {
1322                 .name = "bq27000-battery",
1323         },
1324 };
1325
1326 static inline int bq27xxx_battery_platform_init(void)
1327 {
1328         int ret = platform_driver_register(&bq27xxx_battery_platform_driver);
1329
1330         if (ret)
1331                 pr_err("Unable to register BQ27xxx platform driver\n");
1332
1333         return ret;
1334 }
1335
1336 static inline void bq27xxx_battery_platform_exit(void)
1337 {
1338         platform_driver_unregister(&bq27xxx_battery_platform_driver);
1339 }
1340
1341 #else
1342
1343 static inline int bq27xxx_battery_platform_init(void) { return 0; }
1344 static inline void bq27xxx_battery_platform_exit(void) {};
1345
1346 #endif
1347
1348 /*
1349  * Module stuff
1350  */
1351
1352 static int __init bq27xxx_battery_init(void)
1353 {
1354         int ret;
1355
1356         ret = bq27xxx_battery_i2c_init();
1357         if (ret)
1358                 return ret;
1359
1360         ret = bq27xxx_battery_platform_init();
1361         if (ret)
1362                 bq27xxx_battery_i2c_exit();
1363
1364         return ret;
1365 }
1366 module_init(bq27xxx_battery_init);
1367
1368 static void __exit bq27xxx_battery_exit(void)
1369 {
1370         bq27xxx_battery_platform_exit();
1371         bq27xxx_battery_i2c_exit();
1372 }
1373 module_exit(bq27xxx_battery_exit);
1374
1375 #ifdef CONFIG_BATTERY_BQ27XXX_PLATFORM
1376 MODULE_ALIAS("platform:bq27000-battery");
1377 #endif
1378
1379 MODULE_AUTHOR("Rodolfo Giometti <giometti@linux.it>");
1380 MODULE_DESCRIPTION("BQ27xxx battery monitor driver");
1381 MODULE_LICENSE("GPL");