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/mutex.h>
43 #include <linux/param.h>
44 #include <linux/jiffies.h>
45 #include <linux/workqueue.h>
46 #include <linux/delay.h>
47 #include <linux/platform_device.h>
48 #include <linux/power_supply.h>
49 #include <linux/slab.h>
50 #include <linux/of.h>
51 
52 #include <linux/power/bq27xxx_battery.h>
53 
54 #define DRIVER_VERSION		"1.2.0"
55 
56 #define BQ27XXX_MANUFACTURER	"Texas Instruments"
57 
58 /* BQ27XXX Flags */
59 #define BQ27XXX_FLAG_DSC	BIT(0)
60 #define BQ27XXX_FLAG_SOCF	BIT(1) /* State-of-Charge threshold final */
61 #define BQ27XXX_FLAG_SOC1	BIT(2) /* State-of-Charge threshold 1 */
62 #define BQ27XXX_FLAG_FC		BIT(9)
63 #define BQ27XXX_FLAG_OTD	BIT(14)
64 #define BQ27XXX_FLAG_OTC	BIT(15)
65 #define BQ27XXX_FLAG_UT		BIT(14)
66 #define BQ27XXX_FLAG_OT		BIT(15)
67 
68 /* BQ27000 has different layout for Flags register */
69 #define BQ27000_FLAG_EDVF	BIT(0) /* Final End-of-Discharge-Voltage flag */
70 #define BQ27000_FLAG_EDV1	BIT(1) /* First End-of-Discharge-Voltage flag */
71 #define BQ27000_FLAG_CI		BIT(4) /* Capacity Inaccurate flag */
72 #define BQ27000_FLAG_FC		BIT(5)
73 #define BQ27000_FLAG_CHGS	BIT(7) /* Charge state flag */
74 
75 #define BQ27XXX_RS			(20) /* Resistor sense mOhm */
76 #define BQ27XXX_POWER_CONSTANT		(29200) /* 29.2 µV^2 * 1000 */
77 #define BQ27XXX_CURRENT_CONSTANT	(3570) /* 3.57 µV * 1000 */
78 
79 #define INVALID_REG_ADDR	0xff
80 
81 /*
82  * bq27xxx_reg_index - Register names
83  *
84  * These are indexes into a device's register mapping array.
85  */
86 
87 enum bq27xxx_reg_index {
88 	BQ27XXX_REG_CTRL = 0,	/* Control */
89 	BQ27XXX_REG_TEMP,	/* Temperature */
90 	BQ27XXX_REG_INT_TEMP,	/* Internal Temperature */
91 	BQ27XXX_REG_VOLT,	/* Voltage */
92 	BQ27XXX_REG_AI,		/* Average Current */
93 	BQ27XXX_REG_FLAGS,	/* Flags */
94 	BQ27XXX_REG_TTE,	/* Time-to-Empty */
95 	BQ27XXX_REG_TTF,	/* Time-to-Full */
96 	BQ27XXX_REG_TTES,	/* Time-to-Empty Standby */
97 	BQ27XXX_REG_TTECP,	/* Time-to-Empty at Constant Power */
98 	BQ27XXX_REG_NAC,	/* Nominal Available Capacity */
99 	BQ27XXX_REG_FCC,	/* Full Charge Capacity */
100 	BQ27XXX_REG_CYCT,	/* Cycle Count */
101 	BQ27XXX_REG_AE,		/* Available Energy */
102 	BQ27XXX_REG_SOC,	/* State-of-Charge */
103 	BQ27XXX_REG_DCAP,	/* Design Capacity */
104 	BQ27XXX_REG_AP,		/* Average Power */
105 	BQ27XXX_REG_MAX,	/* sentinel */
106 };
107 
108 /* Register mappings */
109 static u8 bq27xxx_regs[][BQ27XXX_REG_MAX] = {
110 	[BQ27000] = {
111 		[BQ27XXX_REG_CTRL] = 0x00,
112 		[BQ27XXX_REG_TEMP] = 0x06,
113 		[BQ27XXX_REG_INT_TEMP] = INVALID_REG_ADDR,
114 		[BQ27XXX_REG_VOLT] = 0x08,
115 		[BQ27XXX_REG_AI] = 0x14,
116 		[BQ27XXX_REG_FLAGS] = 0x0a,
117 		[BQ27XXX_REG_TTE] = 0x16,
118 		[BQ27XXX_REG_TTF] = 0x18,
119 		[BQ27XXX_REG_TTES] = 0x1c,
120 		[BQ27XXX_REG_TTECP] = 0x26,
121 		[BQ27XXX_REG_NAC] = 0x0c,
122 		[BQ27XXX_REG_FCC] = 0x12,
123 		[BQ27XXX_REG_CYCT] = 0x2a,
124 		[BQ27XXX_REG_AE] = 0x22,
125 		[BQ27XXX_REG_SOC] = 0x0b,
126 		[BQ27XXX_REG_DCAP] = 0x76,
127 		[BQ27XXX_REG_AP] = 0x24,
128 	},
129 	[BQ27010] = {
130 		[BQ27XXX_REG_CTRL] = 0x00,
131 		[BQ27XXX_REG_TEMP] = 0x06,
132 		[BQ27XXX_REG_INT_TEMP] = INVALID_REG_ADDR,
133 		[BQ27XXX_REG_VOLT] = 0x08,
134 		[BQ27XXX_REG_AI] = 0x14,
135 		[BQ27XXX_REG_FLAGS] = 0x0a,
136 		[BQ27XXX_REG_TTE] = 0x16,
137 		[BQ27XXX_REG_TTF] = 0x18,
138 		[BQ27XXX_REG_TTES] = 0x1c,
139 		[BQ27XXX_REG_TTECP] = 0x26,
140 		[BQ27XXX_REG_NAC] = 0x0c,
141 		[BQ27XXX_REG_FCC] = 0x12,
142 		[BQ27XXX_REG_CYCT] = 0x2a,
143 		[BQ27XXX_REG_AE] = INVALID_REG_ADDR,
144 		[BQ27XXX_REG_SOC] = 0x0b,
145 		[BQ27XXX_REG_DCAP] = 0x76,
146 		[BQ27XXX_REG_AP] = INVALID_REG_ADDR,
147 	},
148 	[BQ27500] = {
149 		[BQ27XXX_REG_CTRL] = 0x00,
150 		[BQ27XXX_REG_TEMP] = 0x06,
151 		[BQ27XXX_REG_INT_TEMP] = 0x28,
152 		[BQ27XXX_REG_VOLT] = 0x08,
153 		[BQ27XXX_REG_AI] = 0x14,
154 		[BQ27XXX_REG_FLAGS] = 0x0a,
155 		[BQ27XXX_REG_TTE] = 0x16,
156 		[BQ27XXX_REG_TTF] = INVALID_REG_ADDR,
157 		[BQ27XXX_REG_TTES] = 0x1a,
158 		[BQ27XXX_REG_TTECP] = INVALID_REG_ADDR,
159 		[BQ27XXX_REG_NAC] = 0x0c,
160 		[BQ27XXX_REG_FCC] = 0x12,
161 		[BQ27XXX_REG_CYCT] = 0x2a,
162 		[BQ27XXX_REG_AE] = INVALID_REG_ADDR,
163 		[BQ27XXX_REG_SOC] = 0x2c,
164 		[BQ27XXX_REG_DCAP] = 0x3c,
165 		[BQ27XXX_REG_AP] = INVALID_REG_ADDR,
166 	},
167 	[BQ27510] = {
168 		[BQ27XXX_REG_CTRL] = 0x00,
169 		[BQ27XXX_REG_TEMP] = 0x06,
170 		[BQ27XXX_REG_INT_TEMP] = 0x28,
171 		[BQ27XXX_REG_VOLT] = 0x08,
172 		[BQ27XXX_REG_AI] = 0x14,
173 		[BQ27XXX_REG_FLAGS] = 0x0a,
174 		[BQ27XXX_REG_TTE] = 0x16,
175 		[BQ27XXX_REG_TTF] = INVALID_REG_ADDR,
176 		[BQ27XXX_REG_TTES] = 0x1a,
177 		[BQ27XXX_REG_TTECP] = INVALID_REG_ADDR,
178 		[BQ27XXX_REG_NAC] = 0x0c,
179 		[BQ27XXX_REG_FCC] = 0x12,
180 		[BQ27XXX_REG_CYCT] = 0x1e,
181 		[BQ27XXX_REG_AE] = INVALID_REG_ADDR,
182 		[BQ27XXX_REG_SOC] = 0x20,
183 		[BQ27XXX_REG_DCAP] = 0x2e,
184 		[BQ27XXX_REG_AP] = INVALID_REG_ADDR,
185 	},
186 	[BQ27530] = {
187 		[BQ27XXX_REG_CTRL] = 0x00,
188 		[BQ27XXX_REG_TEMP] = 0x06,
189 		[BQ27XXX_REG_INT_TEMP] = 0x32,
190 		[BQ27XXX_REG_VOLT] = 0x08,
191 		[BQ27XXX_REG_AI] = 0x14,
192 		[BQ27XXX_REG_FLAGS] = 0x0a,
193 		[BQ27XXX_REG_TTE] = 0x16,
194 		[BQ27XXX_REG_TTF] = INVALID_REG_ADDR,
195 		[BQ27XXX_REG_TTES] = INVALID_REG_ADDR,
196 		[BQ27XXX_REG_TTECP] = INVALID_REG_ADDR,
197 		[BQ27XXX_REG_NAC] = 0x0c,
198 		[BQ27XXX_REG_FCC] = 0x12,
199 		[BQ27XXX_REG_CYCT] = 0x2a,
200 		[BQ27XXX_REG_AE] = INVALID_REG_ADDR,
201 		[BQ27XXX_REG_SOC] = 0x2c,
202 		[BQ27XXX_REG_DCAP] = INVALID_REG_ADDR,
203 		[BQ27XXX_REG_AP] = 0x24,
204 	},
205 	[BQ27541] = {
206 		[BQ27XXX_REG_CTRL] = 0x00,
207 		[BQ27XXX_REG_TEMP] = 0x06,
208 		[BQ27XXX_REG_INT_TEMP] = 0x28,
209 		[BQ27XXX_REG_VOLT] = 0x08,
210 		[BQ27XXX_REG_AI] = 0x14,
211 		[BQ27XXX_REG_FLAGS] = 0x0a,
212 		[BQ27XXX_REG_TTE] = 0x16,
213 		[BQ27XXX_REG_TTF] = INVALID_REG_ADDR,
214 		[BQ27XXX_REG_TTES] = INVALID_REG_ADDR,
215 		[BQ27XXX_REG_TTECP] = INVALID_REG_ADDR,
216 		[BQ27XXX_REG_NAC] = 0x0c,
217 		[BQ27XXX_REG_FCC] = 0x12,
218 		[BQ27XXX_REG_CYCT] = 0x2a,
219 		[BQ27XXX_REG_AE] = INVALID_REG_ADDR,
220 		[BQ27XXX_REG_SOC] = 0x2c,
221 		[BQ27XXX_REG_DCAP] = 0x3c,
222 		[BQ27XXX_REG_AP] = 0x24,
223 	},
224 	[BQ27545] = {
225 		[BQ27XXX_REG_CTRL] = 0x00,
226 		[BQ27XXX_REG_TEMP] = 0x06,
227 		[BQ27XXX_REG_INT_TEMP] = 0x28,
228 		[BQ27XXX_REG_VOLT] = 0x08,
229 		[BQ27XXX_REG_AI] = 0x14,
230 		[BQ27XXX_REG_FLAGS] = 0x0a,
231 		[BQ27XXX_REG_TTE] = 0x16,
232 		[BQ27XXX_REG_TTF] = INVALID_REG_ADDR,
233 		[BQ27XXX_REG_TTES] = INVALID_REG_ADDR,
234 		[BQ27XXX_REG_TTECP] = INVALID_REG_ADDR,
235 		[BQ27XXX_REG_NAC] = 0x0c,
236 		[BQ27XXX_REG_FCC] = 0x12,
237 		[BQ27XXX_REG_CYCT] = 0x2a,
238 		[BQ27XXX_REG_AE] = INVALID_REG_ADDR,
239 		[BQ27XXX_REG_SOC] = 0x2c,
240 		[BQ27XXX_REG_DCAP] = INVALID_REG_ADDR,
241 		[BQ27XXX_REG_AP] = 0x24,
242 	},
243 	[BQ27421] = {
244 		[BQ27XXX_REG_CTRL] = 0x00,
245 		[BQ27XXX_REG_TEMP] = 0x02,
246 		[BQ27XXX_REG_INT_TEMP] = 0x1e,
247 		[BQ27XXX_REG_VOLT] = 0x04,
248 		[BQ27XXX_REG_AI] = 0x10,
249 		[BQ27XXX_REG_FLAGS] = 0x06,
250 		[BQ27XXX_REG_TTE] = INVALID_REG_ADDR,
251 		[BQ27XXX_REG_TTF] = INVALID_REG_ADDR,
252 		[BQ27XXX_REG_TTES] = INVALID_REG_ADDR,
253 		[BQ27XXX_REG_TTECP] = INVALID_REG_ADDR,
254 		[BQ27XXX_REG_NAC] = 0x08,
255 		[BQ27XXX_REG_FCC] = 0x0e,
256 		[BQ27XXX_REG_CYCT] = INVALID_REG_ADDR,
257 		[BQ27XXX_REG_AE] = INVALID_REG_ADDR,
258 		[BQ27XXX_REG_SOC] = 0x1c,
259 		[BQ27XXX_REG_DCAP] = 0x3c,
260 		[BQ27XXX_REG_AP] = 0x18,
261 	},
262 };
263 
264 static enum power_supply_property bq27000_battery_props[] = {
265 	POWER_SUPPLY_PROP_STATUS,
266 	POWER_SUPPLY_PROP_PRESENT,
267 	POWER_SUPPLY_PROP_VOLTAGE_NOW,
268 	POWER_SUPPLY_PROP_CURRENT_NOW,
269 	POWER_SUPPLY_PROP_CAPACITY,
270 	POWER_SUPPLY_PROP_CAPACITY_LEVEL,
271 	POWER_SUPPLY_PROP_TEMP,
272 	POWER_SUPPLY_PROP_TIME_TO_EMPTY_NOW,
273 	POWER_SUPPLY_PROP_TIME_TO_EMPTY_AVG,
274 	POWER_SUPPLY_PROP_TIME_TO_FULL_NOW,
275 	POWER_SUPPLY_PROP_TECHNOLOGY,
276 	POWER_SUPPLY_PROP_CHARGE_FULL,
277 	POWER_SUPPLY_PROP_CHARGE_NOW,
278 	POWER_SUPPLY_PROP_CHARGE_FULL_DESIGN,
279 	POWER_SUPPLY_PROP_CYCLE_COUNT,
280 	POWER_SUPPLY_PROP_ENERGY_NOW,
281 	POWER_SUPPLY_PROP_POWER_AVG,
282 	POWER_SUPPLY_PROP_HEALTH,
283 	POWER_SUPPLY_PROP_MANUFACTURER,
284 };
285 
286 static enum power_supply_property bq27010_battery_props[] = {
287 	POWER_SUPPLY_PROP_STATUS,
288 	POWER_SUPPLY_PROP_PRESENT,
289 	POWER_SUPPLY_PROP_VOLTAGE_NOW,
290 	POWER_SUPPLY_PROP_CURRENT_NOW,
291 	POWER_SUPPLY_PROP_CAPACITY,
292 	POWER_SUPPLY_PROP_CAPACITY_LEVEL,
293 	POWER_SUPPLY_PROP_TEMP,
294 	POWER_SUPPLY_PROP_TIME_TO_EMPTY_NOW,
295 	POWER_SUPPLY_PROP_TIME_TO_EMPTY_AVG,
296 	POWER_SUPPLY_PROP_TIME_TO_FULL_NOW,
297 	POWER_SUPPLY_PROP_TECHNOLOGY,
298 	POWER_SUPPLY_PROP_CHARGE_FULL,
299 	POWER_SUPPLY_PROP_CHARGE_NOW,
300 	POWER_SUPPLY_PROP_CHARGE_FULL_DESIGN,
301 	POWER_SUPPLY_PROP_CYCLE_COUNT,
302 	POWER_SUPPLY_PROP_HEALTH,
303 	POWER_SUPPLY_PROP_MANUFACTURER,
304 };
305 
306 static enum power_supply_property bq27500_battery_props[] = {
307 	POWER_SUPPLY_PROP_STATUS,
308 	POWER_SUPPLY_PROP_PRESENT,
309 	POWER_SUPPLY_PROP_VOLTAGE_NOW,
310 	POWER_SUPPLY_PROP_CURRENT_NOW,
311 	POWER_SUPPLY_PROP_CAPACITY,
312 	POWER_SUPPLY_PROP_CAPACITY_LEVEL,
313 	POWER_SUPPLY_PROP_TEMP,
314 	POWER_SUPPLY_PROP_TIME_TO_EMPTY_NOW,
315 	POWER_SUPPLY_PROP_TECHNOLOGY,
316 	POWER_SUPPLY_PROP_CHARGE_FULL,
317 	POWER_SUPPLY_PROP_CHARGE_NOW,
318 	POWER_SUPPLY_PROP_CHARGE_FULL_DESIGN,
319 	POWER_SUPPLY_PROP_CYCLE_COUNT,
320 	POWER_SUPPLY_PROP_HEALTH,
321 	POWER_SUPPLY_PROP_MANUFACTURER,
322 };
323 
324 static enum power_supply_property bq27510_battery_props[] = {
325 	POWER_SUPPLY_PROP_STATUS,
326 	POWER_SUPPLY_PROP_PRESENT,
327 	POWER_SUPPLY_PROP_VOLTAGE_NOW,
328 	POWER_SUPPLY_PROP_CURRENT_NOW,
329 	POWER_SUPPLY_PROP_CAPACITY,
330 	POWER_SUPPLY_PROP_CAPACITY_LEVEL,
331 	POWER_SUPPLY_PROP_TEMP,
332 	POWER_SUPPLY_PROP_TIME_TO_EMPTY_NOW,
333 	POWER_SUPPLY_PROP_TECHNOLOGY,
334 	POWER_SUPPLY_PROP_CHARGE_FULL,
335 	POWER_SUPPLY_PROP_CHARGE_NOW,
336 	POWER_SUPPLY_PROP_CHARGE_FULL_DESIGN,
337 	POWER_SUPPLY_PROP_CYCLE_COUNT,
338 	POWER_SUPPLY_PROP_HEALTH,
339 	POWER_SUPPLY_PROP_MANUFACTURER,
340 };
341 
342 static enum power_supply_property bq27530_battery_props[] = {
343 	POWER_SUPPLY_PROP_STATUS,
344 	POWER_SUPPLY_PROP_PRESENT,
345 	POWER_SUPPLY_PROP_VOLTAGE_NOW,
346 	POWER_SUPPLY_PROP_CURRENT_NOW,
347 	POWER_SUPPLY_PROP_CAPACITY,
348 	POWER_SUPPLY_PROP_CAPACITY_LEVEL,
349 	POWER_SUPPLY_PROP_TEMP,
350 	POWER_SUPPLY_PROP_TIME_TO_EMPTY_NOW,
351 	POWER_SUPPLY_PROP_TECHNOLOGY,
352 	POWER_SUPPLY_PROP_CHARGE_FULL,
353 	POWER_SUPPLY_PROP_CHARGE_NOW,
354 	POWER_SUPPLY_PROP_POWER_AVG,
355 	POWER_SUPPLY_PROP_HEALTH,
356 	POWER_SUPPLY_PROP_CYCLE_COUNT,
357 	POWER_SUPPLY_PROP_MANUFACTURER,
358 };
359 
360 static enum power_supply_property bq27541_battery_props[] = {
361 	POWER_SUPPLY_PROP_STATUS,
362 	POWER_SUPPLY_PROP_PRESENT,
363 	POWER_SUPPLY_PROP_VOLTAGE_NOW,
364 	POWER_SUPPLY_PROP_CURRENT_NOW,
365 	POWER_SUPPLY_PROP_CAPACITY,
366 	POWER_SUPPLY_PROP_CAPACITY_LEVEL,
367 	POWER_SUPPLY_PROP_TEMP,
368 	POWER_SUPPLY_PROP_TIME_TO_EMPTY_NOW,
369 	POWER_SUPPLY_PROP_TECHNOLOGY,
370 	POWER_SUPPLY_PROP_CHARGE_FULL,
371 	POWER_SUPPLY_PROP_CHARGE_NOW,
372 	POWER_SUPPLY_PROP_CHARGE_FULL_DESIGN,
373 	POWER_SUPPLY_PROP_CYCLE_COUNT,
374 	POWER_SUPPLY_PROP_POWER_AVG,
375 	POWER_SUPPLY_PROP_HEALTH,
376 	POWER_SUPPLY_PROP_MANUFACTURER,
377 };
378 
379 static enum power_supply_property bq27545_battery_props[] = {
380 	POWER_SUPPLY_PROP_STATUS,
381 	POWER_SUPPLY_PROP_PRESENT,
382 	POWER_SUPPLY_PROP_VOLTAGE_NOW,
383 	POWER_SUPPLY_PROP_CURRENT_NOW,
384 	POWER_SUPPLY_PROP_CAPACITY,
385 	POWER_SUPPLY_PROP_CAPACITY_LEVEL,
386 	POWER_SUPPLY_PROP_TEMP,
387 	POWER_SUPPLY_PROP_TIME_TO_EMPTY_NOW,
388 	POWER_SUPPLY_PROP_TECHNOLOGY,
389 	POWER_SUPPLY_PROP_CHARGE_FULL,
390 	POWER_SUPPLY_PROP_CHARGE_NOW,
391 	POWER_SUPPLY_PROP_HEALTH,
392 	POWER_SUPPLY_PROP_CYCLE_COUNT,
393 	POWER_SUPPLY_PROP_POWER_AVG,
394 	POWER_SUPPLY_PROP_MANUFACTURER,
395 };
396 
397 static enum power_supply_property bq27421_battery_props[] = {
398 	POWER_SUPPLY_PROP_STATUS,
399 	POWER_SUPPLY_PROP_PRESENT,
400 	POWER_SUPPLY_PROP_VOLTAGE_NOW,
401 	POWER_SUPPLY_PROP_CURRENT_NOW,
402 	POWER_SUPPLY_PROP_CAPACITY,
403 	POWER_SUPPLY_PROP_CAPACITY_LEVEL,
404 	POWER_SUPPLY_PROP_TEMP,
405 	POWER_SUPPLY_PROP_TECHNOLOGY,
406 	POWER_SUPPLY_PROP_CHARGE_FULL,
407 	POWER_SUPPLY_PROP_CHARGE_NOW,
408 	POWER_SUPPLY_PROP_CHARGE_FULL_DESIGN,
409 	POWER_SUPPLY_PROP_MANUFACTURER,
410 };
411 
412 #define BQ27XXX_PROP(_id, _prop)		\
413 	[_id] = {				\
414 		.props = _prop,			\
415 		.size = ARRAY_SIZE(_prop),	\
416 	}
417 
418 static struct {
419 	enum power_supply_property *props;
420 	size_t size;
421 } bq27xxx_battery_props[] = {
422 	BQ27XXX_PROP(BQ27000, bq27000_battery_props),
423 	BQ27XXX_PROP(BQ27010, bq27010_battery_props),
424 	BQ27XXX_PROP(BQ27500, bq27500_battery_props),
425 	BQ27XXX_PROP(BQ27510, bq27510_battery_props),
426 	BQ27XXX_PROP(BQ27530, bq27530_battery_props),
427 	BQ27XXX_PROP(BQ27541, bq27541_battery_props),
428 	BQ27XXX_PROP(BQ27545, bq27545_battery_props),
429 	BQ27XXX_PROP(BQ27421, bq27421_battery_props),
430 };
431 
432 static DEFINE_MUTEX(bq27xxx_list_lock);
433 static LIST_HEAD(bq27xxx_battery_devices);
434 
435 static int poll_interval_param_set(const char *val, const struct kernel_param *kp)
436 {
437 	struct bq27xxx_device_info *di;
438 	unsigned int prev_val = *(unsigned int *) kp->arg;
439 	int ret;
440 
441 	ret = param_set_uint(val, kp);
442 	if (ret < 0 || prev_val == *(unsigned int *) kp->arg)
443 		return ret;
444 
445 	mutex_lock(&bq27xxx_list_lock);
446 	list_for_each_entry(di, &bq27xxx_battery_devices, list) {
447 		cancel_delayed_work_sync(&di->work);
448 		schedule_delayed_work(&di->work, 0);
449 	}
450 	mutex_unlock(&bq27xxx_list_lock);
451 
452 	return ret;
453 }
454 
455 static const struct kernel_param_ops param_ops_poll_interval = {
456 	.get = param_get_uint,
457 	.set = poll_interval_param_set,
458 };
459 
460 static unsigned int poll_interval = 360;
461 module_param_cb(poll_interval, &param_ops_poll_interval, &poll_interval, 0644);
462 MODULE_PARM_DESC(poll_interval,
463 		 "battery poll interval in seconds - 0 disables polling");
464 
465 /*
466  * Common code for BQ27xxx devices
467  */
468 
469 static inline int bq27xxx_read(struct bq27xxx_device_info *di, int reg_index,
470 			       bool single)
471 {
472 	/* Reports EINVAL for invalid/missing registers */
473 	if (!di || di->regs[reg_index] == INVALID_REG_ADDR)
474 		return -EINVAL;
475 
476 	return di->bus.read(di, di->regs[reg_index], single);
477 }
478 
479 /*
480  * Return the battery State-of-Charge
481  * Or < 0 if something fails.
482  */
483 static int bq27xxx_battery_read_soc(struct bq27xxx_device_info *di)
484 {
485 	int soc;
486 
487 	if (di->chip == BQ27000 || di->chip == BQ27010)
488 		soc = bq27xxx_read(di, BQ27XXX_REG_SOC, true);
489 	else
490 		soc = bq27xxx_read(di, BQ27XXX_REG_SOC, false);
491 
492 	if (soc < 0)
493 		dev_dbg(di->dev, "error reading State-of-Charge\n");
494 
495 	return soc;
496 }
497 
498 /*
499  * Return a battery charge value in µAh
500  * Or < 0 if something fails.
501  */
502 static int bq27xxx_battery_read_charge(struct bq27xxx_device_info *di, u8 reg)
503 {
504 	int charge;
505 
506 	charge = bq27xxx_read(di, reg, false);
507 	if (charge < 0) {
508 		dev_dbg(di->dev, "error reading charge register %02x: %d\n",
509 			reg, charge);
510 		return charge;
511 	}
512 
513 	if (di->chip == BQ27000 || di->chip == BQ27010)
514 		charge *= BQ27XXX_CURRENT_CONSTANT / BQ27XXX_RS;
515 	else
516 		charge *= 1000;
517 
518 	return charge;
519 }
520 
521 /*
522  * Return the battery Nominal available capacity in µAh
523  * Or < 0 if something fails.
524  */
525 static inline int bq27xxx_battery_read_nac(struct bq27xxx_device_info *di)
526 {
527 	int flags;
528 
529 	if (di->chip == BQ27000 || di->chip == BQ27010) {
530 		flags = bq27xxx_read(di, BQ27XXX_REG_FLAGS, true);
531 		if (flags >= 0 && (flags & BQ27000_FLAG_CI))
532 			return -ENODATA;
533 	}
534 
535 	return bq27xxx_battery_read_charge(di, BQ27XXX_REG_NAC);
536 }
537 
538 /*
539  * Return the battery Full Charge Capacity in µAh
540  * Or < 0 if something fails.
541  */
542 static inline int bq27xxx_battery_read_fcc(struct bq27xxx_device_info *di)
543 {
544 	return bq27xxx_battery_read_charge(di, BQ27XXX_REG_FCC);
545 }
546 
547 /*
548  * Return the Design Capacity in µAh
549  * Or < 0 if something fails.
550  */
551 static int bq27xxx_battery_read_dcap(struct bq27xxx_device_info *di)
552 {
553 	int dcap;
554 
555 	if (di->chip == BQ27000 || di->chip == BQ27010)
556 		dcap = bq27xxx_read(di, BQ27XXX_REG_DCAP, true);
557 	else
558 		dcap = bq27xxx_read(di, BQ27XXX_REG_DCAP, false);
559 
560 	if (dcap < 0) {
561 		dev_dbg(di->dev, "error reading initial last measured discharge\n");
562 		return dcap;
563 	}
564 
565 	if (di->chip == BQ27000 || di->chip == BQ27010)
566 		dcap = (dcap << 8) * BQ27XXX_CURRENT_CONSTANT / BQ27XXX_RS;
567 	else
568 		dcap *= 1000;
569 
570 	return dcap;
571 }
572 
573 /*
574  * Return the battery Available energy in µWh
575  * Or < 0 if something fails.
576  */
577 static int bq27xxx_battery_read_energy(struct bq27xxx_device_info *di)
578 {
579 	int ae;
580 
581 	ae = bq27xxx_read(di, BQ27XXX_REG_AE, false);
582 	if (ae < 0) {
583 		dev_dbg(di->dev, "error reading available energy\n");
584 		return ae;
585 	}
586 
587 	if (di->chip == BQ27000 || di->chip == BQ27010)
588 		ae *= BQ27XXX_POWER_CONSTANT / BQ27XXX_RS;
589 	else
590 		ae *= 1000;
591 
592 	return ae;
593 }
594 
595 /*
596  * Return the battery temperature in tenths of degree Kelvin
597  * Or < 0 if something fails.
598  */
599 static int bq27xxx_battery_read_temperature(struct bq27xxx_device_info *di)
600 {
601 	int temp;
602 
603 	temp = bq27xxx_read(di, BQ27XXX_REG_TEMP, false);
604 	if (temp < 0) {
605 		dev_err(di->dev, "error reading temperature\n");
606 		return temp;
607 	}
608 
609 	if (di->chip == BQ27000 || di->chip == BQ27010)
610 		temp = 5 * temp / 2;
611 
612 	return temp;
613 }
614 
615 /*
616  * Return the battery Cycle count total
617  * Or < 0 if something fails.
618  */
619 static int bq27xxx_battery_read_cyct(struct bq27xxx_device_info *di)
620 {
621 	int cyct;
622 
623 	cyct = bq27xxx_read(di, BQ27XXX_REG_CYCT, false);
624 	if (cyct < 0)
625 		dev_err(di->dev, "error reading cycle count total\n");
626 
627 	return cyct;
628 }
629 
630 /*
631  * Read a time register.
632  * Return < 0 if something fails.
633  */
634 static int bq27xxx_battery_read_time(struct bq27xxx_device_info *di, u8 reg)
635 {
636 	int tval;
637 
638 	tval = bq27xxx_read(di, reg, false);
639 	if (tval < 0) {
640 		dev_dbg(di->dev, "error reading time register %02x: %d\n",
641 			reg, tval);
642 		return tval;
643 	}
644 
645 	if (tval == 65535)
646 		return -ENODATA;
647 
648 	return tval * 60;
649 }
650 
651 /*
652  * Read an average power register.
653  * Return < 0 if something fails.
654  */
655 static int bq27xxx_battery_read_pwr_avg(struct bq27xxx_device_info *di)
656 {
657 	int tval;
658 
659 	tval = bq27xxx_read(di, BQ27XXX_REG_AP, false);
660 	if (tval < 0) {
661 		dev_err(di->dev, "error reading average power register  %02x: %d\n",
662 			BQ27XXX_REG_AP, tval);
663 		return tval;
664 	}
665 
666 	if (di->chip == BQ27000 || di->chip == BQ27010)
667 		return (tval * BQ27XXX_POWER_CONSTANT) / BQ27XXX_RS;
668 	else
669 		return tval;
670 }
671 
672 /*
673  * Returns true if a battery over temperature condition is detected
674  */
675 static bool bq27xxx_battery_overtemp(struct bq27xxx_device_info *di, u16 flags)
676 {
677 	if (di->chip == BQ27500 || di->chip == BQ27510 ||
678 	    di->chip == BQ27541 || di->chip == BQ27545)
679 		return flags & (BQ27XXX_FLAG_OTC | BQ27XXX_FLAG_OTD);
680 	if (di->chip == BQ27530 || di->chip == BQ27421)
681 		return flags & BQ27XXX_FLAG_OT;
682 
683 	return false;
684 }
685 
686 /*
687  * Returns true if a battery under temperature condition is detected
688  */
689 static bool bq27xxx_battery_undertemp(struct bq27xxx_device_info *di, u16 flags)
690 {
691 	if (di->chip == BQ27530 || di->chip == BQ27421)
692 		return flags & BQ27XXX_FLAG_UT;
693 
694 	return false;
695 }
696 
697 /*
698  * Returns true if a low state of charge condition is detected
699  */
700 static bool bq27xxx_battery_dead(struct bq27xxx_device_info *di, u16 flags)
701 {
702 	if (di->chip == BQ27000 || di->chip == BQ27010)
703 		return flags & (BQ27000_FLAG_EDV1 | BQ27000_FLAG_EDVF);
704 	else
705 		return flags & (BQ27XXX_FLAG_SOC1 | BQ27XXX_FLAG_SOCF);
706 }
707 
708 /*
709  * Read flag register.
710  * Return < 0 if something fails.
711  */
712 static int bq27xxx_battery_read_health(struct bq27xxx_device_info *di)
713 {
714 	int flags;
715 	bool has_singe_flag = di->chip == BQ27000 || di->chip == BQ27010;
716 
717 	flags = bq27xxx_read(di, BQ27XXX_REG_FLAGS, has_singe_flag);
718 	if (flags < 0) {
719 		dev_err(di->dev, "error reading flag register:%d\n", flags);
720 		return flags;
721 	}
722 
723 	/* Unlikely but important to return first */
724 	if (unlikely(bq27xxx_battery_overtemp(di, flags)))
725 		return POWER_SUPPLY_HEALTH_OVERHEAT;
726 	if (unlikely(bq27xxx_battery_undertemp(di, flags)))
727 		return POWER_SUPPLY_HEALTH_COLD;
728 	if (unlikely(bq27xxx_battery_dead(di, flags)))
729 		return POWER_SUPPLY_HEALTH_DEAD;
730 
731 	return POWER_SUPPLY_HEALTH_GOOD;
732 }
733 
734 void bq27xxx_battery_update(struct bq27xxx_device_info *di)
735 {
736 	struct bq27xxx_reg_cache cache = {0, };
737 	bool has_ci_flag = di->chip == BQ27000 || di->chip == BQ27010;
738 	bool has_singe_flag = di->chip == BQ27000 || di->chip == BQ27010;
739 
740 	cache.flags = bq27xxx_read(di, BQ27XXX_REG_FLAGS, has_singe_flag);
741 	if ((cache.flags & 0xff) == 0xff)
742 		cache.flags = -1; /* read error */
743 	if (cache.flags >= 0) {
744 		cache.temperature = bq27xxx_battery_read_temperature(di);
745 		if (has_ci_flag && (cache.flags & BQ27000_FLAG_CI)) {
746 			dev_info_once(di->dev, "battery is not calibrated! ignoring capacity values\n");
747 			cache.capacity = -ENODATA;
748 			cache.energy = -ENODATA;
749 			cache.time_to_empty = -ENODATA;
750 			cache.time_to_empty_avg = -ENODATA;
751 			cache.time_to_full = -ENODATA;
752 			cache.charge_full = -ENODATA;
753 			cache.health = -ENODATA;
754 		} else {
755 			if (di->regs[BQ27XXX_REG_TTE] != INVALID_REG_ADDR)
756 				cache.time_to_empty = bq27xxx_battery_read_time(di, BQ27XXX_REG_TTE);
757 			if (di->regs[BQ27XXX_REG_TTECP] != INVALID_REG_ADDR)
758 				cache.time_to_empty_avg = bq27xxx_battery_read_time(di, BQ27XXX_REG_TTECP);
759 			if (di->regs[BQ27XXX_REG_TTF] != INVALID_REG_ADDR)
760 				cache.time_to_full = bq27xxx_battery_read_time(di, BQ27XXX_REG_TTF);
761 			cache.charge_full = bq27xxx_battery_read_fcc(di);
762 			cache.capacity = bq27xxx_battery_read_soc(di);
763 			if (di->regs[BQ27XXX_REG_AE] != INVALID_REG_ADDR)
764 				cache.energy = bq27xxx_battery_read_energy(di);
765 			cache.health = bq27xxx_battery_read_health(di);
766 		}
767 		if (di->regs[BQ27XXX_REG_CYCT] != INVALID_REG_ADDR)
768 			cache.cycle_count = bq27xxx_battery_read_cyct(di);
769 		if (di->regs[BQ27XXX_REG_AP] != INVALID_REG_ADDR)
770 			cache.power_avg = bq27xxx_battery_read_pwr_avg(di);
771 
772 		/* We only have to read charge design full once */
773 		if (di->charge_design_full <= 0)
774 			di->charge_design_full = bq27xxx_battery_read_dcap(di);
775 	}
776 
777 	if (di->cache.capacity != cache.capacity)
778 		power_supply_changed(di->bat);
779 
780 	if (memcmp(&di->cache, &cache, sizeof(cache)) != 0)
781 		di->cache = cache;
782 
783 	di->last_update = jiffies;
784 }
785 EXPORT_SYMBOL_GPL(bq27xxx_battery_update);
786 
787 static void bq27xxx_battery_poll(struct work_struct *work)
788 {
789 	struct bq27xxx_device_info *di =
790 			container_of(work, struct bq27xxx_device_info,
791 				     work.work);
792 
793 	bq27xxx_battery_update(di);
794 
795 	if (poll_interval > 0)
796 		schedule_delayed_work(&di->work, poll_interval * HZ);
797 }
798 
799 /*
800  * Return the battery average current in µA
801  * Note that current can be negative signed as well
802  * Or 0 if something fails.
803  */
804 static int bq27xxx_battery_current(struct bq27xxx_device_info *di,
805 				   union power_supply_propval *val)
806 {
807 	int curr;
808 	int flags;
809 
810 	curr = bq27xxx_read(di, BQ27XXX_REG_AI, false);
811 	if (curr < 0) {
812 		dev_err(di->dev, "error reading current\n");
813 		return curr;
814 	}
815 
816 	if (di->chip == BQ27000 || di->chip == BQ27010) {
817 		flags = bq27xxx_read(di, BQ27XXX_REG_FLAGS, true);
818 		if (flags & BQ27000_FLAG_CHGS) {
819 			dev_dbg(di->dev, "negative current!\n");
820 			curr = -curr;
821 		}
822 
823 		val->intval = curr * BQ27XXX_CURRENT_CONSTANT / BQ27XXX_RS;
824 	} else {
825 		/* Other gauges return signed value */
826 		val->intval = (int)((s16)curr) * 1000;
827 	}
828 
829 	return 0;
830 }
831 
832 static int bq27xxx_battery_status(struct bq27xxx_device_info *di,
833 				  union power_supply_propval *val)
834 {
835 	int status;
836 
837 	if (di->chip == BQ27000 || di->chip == BQ27010) {
838 		if (di->cache.flags & BQ27000_FLAG_FC)
839 			status = POWER_SUPPLY_STATUS_FULL;
840 		else if (di->cache.flags & BQ27000_FLAG_CHGS)
841 			status = POWER_SUPPLY_STATUS_CHARGING;
842 		else if (power_supply_am_i_supplied(di->bat))
843 			status = POWER_SUPPLY_STATUS_NOT_CHARGING;
844 		else
845 			status = POWER_SUPPLY_STATUS_DISCHARGING;
846 	} else {
847 		if (di->cache.flags & BQ27XXX_FLAG_FC)
848 			status = POWER_SUPPLY_STATUS_FULL;
849 		else if (di->cache.flags & BQ27XXX_FLAG_DSC)
850 			status = POWER_SUPPLY_STATUS_DISCHARGING;
851 		else
852 			status = POWER_SUPPLY_STATUS_CHARGING;
853 	}
854 
855 	val->intval = status;
856 
857 	return 0;
858 }
859 
860 static int bq27xxx_battery_capacity_level(struct bq27xxx_device_info *di,
861 					  union power_supply_propval *val)
862 {
863 	int level;
864 
865 	if (di->chip == BQ27000 || di->chip == BQ27010) {
866 		if (di->cache.flags & BQ27000_FLAG_FC)
867 			level = POWER_SUPPLY_CAPACITY_LEVEL_FULL;
868 		else if (di->cache.flags & BQ27000_FLAG_EDV1)
869 			level = POWER_SUPPLY_CAPACITY_LEVEL_LOW;
870 		else if (di->cache.flags & BQ27000_FLAG_EDVF)
871 			level = POWER_SUPPLY_CAPACITY_LEVEL_CRITICAL;
872 		else
873 			level = POWER_SUPPLY_CAPACITY_LEVEL_NORMAL;
874 	} else {
875 		if (di->cache.flags & BQ27XXX_FLAG_FC)
876 			level = POWER_SUPPLY_CAPACITY_LEVEL_FULL;
877 		else if (di->cache.flags & BQ27XXX_FLAG_SOC1)
878 			level = POWER_SUPPLY_CAPACITY_LEVEL_LOW;
879 		else if (di->cache.flags & BQ27XXX_FLAG_SOCF)
880 			level = POWER_SUPPLY_CAPACITY_LEVEL_CRITICAL;
881 		else
882 			level = POWER_SUPPLY_CAPACITY_LEVEL_NORMAL;
883 	}
884 
885 	val->intval = level;
886 
887 	return 0;
888 }
889 
890 /*
891  * Return the battery Voltage in millivolts
892  * Or < 0 if something fails.
893  */
894 static int bq27xxx_battery_voltage(struct bq27xxx_device_info *di,
895 				   union power_supply_propval *val)
896 {
897 	int volt;
898 
899 	volt = bq27xxx_read(di, BQ27XXX_REG_VOLT, false);
900 	if (volt < 0) {
901 		dev_err(di->dev, "error reading voltage\n");
902 		return volt;
903 	}
904 
905 	val->intval = volt * 1000;
906 
907 	return 0;
908 }
909 
910 static int bq27xxx_simple_value(int value,
911 				union power_supply_propval *val)
912 {
913 	if (value < 0)
914 		return value;
915 
916 	val->intval = value;
917 
918 	return 0;
919 }
920 
921 static int bq27xxx_battery_get_property(struct power_supply *psy,
922 					enum power_supply_property psp,
923 					union power_supply_propval *val)
924 {
925 	int ret = 0;
926 	struct bq27xxx_device_info *di = power_supply_get_drvdata(psy);
927 
928 	mutex_lock(&di->lock);
929 	if (time_is_before_jiffies(di->last_update + 5 * HZ)) {
930 		cancel_delayed_work_sync(&di->work);
931 		bq27xxx_battery_poll(&di->work.work);
932 	}
933 	mutex_unlock(&di->lock);
934 
935 	if (psp != POWER_SUPPLY_PROP_PRESENT && di->cache.flags < 0)
936 		return -ENODEV;
937 
938 	switch (psp) {
939 	case POWER_SUPPLY_PROP_STATUS:
940 		ret = bq27xxx_battery_status(di, val);
941 		break;
942 	case POWER_SUPPLY_PROP_VOLTAGE_NOW:
943 		ret = bq27xxx_battery_voltage(di, val);
944 		break;
945 	case POWER_SUPPLY_PROP_PRESENT:
946 		val->intval = di->cache.flags < 0 ? 0 : 1;
947 		break;
948 	case POWER_SUPPLY_PROP_CURRENT_NOW:
949 		ret = bq27xxx_battery_current(di, val);
950 		break;
951 	case POWER_SUPPLY_PROP_CAPACITY:
952 		ret = bq27xxx_simple_value(di->cache.capacity, val);
953 		break;
954 	case POWER_SUPPLY_PROP_CAPACITY_LEVEL:
955 		ret = bq27xxx_battery_capacity_level(di, val);
956 		break;
957 	case POWER_SUPPLY_PROP_TEMP:
958 		ret = bq27xxx_simple_value(di->cache.temperature, val);
959 		if (ret == 0)
960 			val->intval -= 2731; /* convert decidegree k to c */
961 		break;
962 	case POWER_SUPPLY_PROP_TIME_TO_EMPTY_NOW:
963 		ret = bq27xxx_simple_value(di->cache.time_to_empty, val);
964 		break;
965 	case POWER_SUPPLY_PROP_TIME_TO_EMPTY_AVG:
966 		ret = bq27xxx_simple_value(di->cache.time_to_empty_avg, val);
967 		break;
968 	case POWER_SUPPLY_PROP_TIME_TO_FULL_NOW:
969 		ret = bq27xxx_simple_value(di->cache.time_to_full, val);
970 		break;
971 	case POWER_SUPPLY_PROP_TECHNOLOGY:
972 		val->intval = POWER_SUPPLY_TECHNOLOGY_LION;
973 		break;
974 	case POWER_SUPPLY_PROP_CHARGE_NOW:
975 		ret = bq27xxx_simple_value(bq27xxx_battery_read_nac(di), val);
976 		break;
977 	case POWER_SUPPLY_PROP_CHARGE_FULL:
978 		ret = bq27xxx_simple_value(di->cache.charge_full, val);
979 		break;
980 	case POWER_SUPPLY_PROP_CHARGE_FULL_DESIGN:
981 		ret = bq27xxx_simple_value(di->charge_design_full, val);
982 		break;
983 	case POWER_SUPPLY_PROP_CYCLE_COUNT:
984 		ret = bq27xxx_simple_value(di->cache.cycle_count, val);
985 		break;
986 	case POWER_SUPPLY_PROP_ENERGY_NOW:
987 		ret = bq27xxx_simple_value(di->cache.energy, val);
988 		break;
989 	case POWER_SUPPLY_PROP_POWER_AVG:
990 		ret = bq27xxx_simple_value(di->cache.power_avg, val);
991 		break;
992 	case POWER_SUPPLY_PROP_HEALTH:
993 		ret = bq27xxx_simple_value(di->cache.health, val);
994 		break;
995 	case POWER_SUPPLY_PROP_MANUFACTURER:
996 		val->strval = BQ27XXX_MANUFACTURER;
997 		break;
998 	default:
999 		return -EINVAL;
1000 	}
1001 
1002 	return ret;
1003 }
1004 
1005 static void bq27xxx_external_power_changed(struct power_supply *psy)
1006 {
1007 	struct bq27xxx_device_info *di = power_supply_get_drvdata(psy);
1008 
1009 	cancel_delayed_work_sync(&di->work);
1010 	schedule_delayed_work(&di->work, 0);
1011 }
1012 
1013 int bq27xxx_battery_setup(struct bq27xxx_device_info *di)
1014 {
1015 	struct power_supply_desc *psy_desc;
1016 	struct power_supply_config psy_cfg = { .drv_data = di, };
1017 
1018 	INIT_DELAYED_WORK(&di->work, bq27xxx_battery_poll);
1019 	mutex_init(&di->lock);
1020 	di->regs = bq27xxx_regs[di->chip];
1021 
1022 	psy_desc = devm_kzalloc(di->dev, sizeof(*psy_desc), GFP_KERNEL);
1023 	if (!psy_desc)
1024 		return -ENOMEM;
1025 
1026 	psy_desc->name = di->name;
1027 	psy_desc->type = POWER_SUPPLY_TYPE_BATTERY;
1028 	psy_desc->properties = bq27xxx_battery_props[di->chip].props;
1029 	psy_desc->num_properties = bq27xxx_battery_props[di->chip].size;
1030 	psy_desc->get_property = bq27xxx_battery_get_property;
1031 	psy_desc->external_power_changed = bq27xxx_external_power_changed;
1032 
1033 	di->bat = power_supply_register_no_ws(di->dev, psy_desc, &psy_cfg);
1034 	if (IS_ERR(di->bat)) {
1035 		dev_err(di->dev, "failed to register battery\n");
1036 		return PTR_ERR(di->bat);
1037 	}
1038 
1039 	dev_info(di->dev, "support ver. %s enabled\n", DRIVER_VERSION);
1040 
1041 	bq27xxx_battery_update(di);
1042 
1043 	mutex_lock(&bq27xxx_list_lock);
1044 	list_add(&di->list, &bq27xxx_battery_devices);
1045 	mutex_unlock(&bq27xxx_list_lock);
1046 
1047 	return 0;
1048 }
1049 EXPORT_SYMBOL_GPL(bq27xxx_battery_setup);
1050 
1051 void bq27xxx_battery_teardown(struct bq27xxx_device_info *di)
1052 {
1053 	/*
1054 	 * power_supply_unregister call bq27xxx_battery_get_property which
1055 	 * call bq27xxx_battery_poll.
1056 	 * Make sure that bq27xxx_battery_poll will not call
1057 	 * schedule_delayed_work again after unregister (which cause OOPS).
1058 	 */
1059 	poll_interval = 0;
1060 
1061 	cancel_delayed_work_sync(&di->work);
1062 
1063 	power_supply_unregister(di->bat);
1064 
1065 	mutex_lock(&bq27xxx_list_lock);
1066 	list_del(&di->list);
1067 	mutex_unlock(&bq27xxx_list_lock);
1068 
1069 	mutex_destroy(&di->lock);
1070 }
1071 EXPORT_SYMBOL_GPL(bq27xxx_battery_teardown);
1072 
1073 static int bq27xxx_battery_platform_read(struct bq27xxx_device_info *di, u8 reg,
1074 					 bool single)
1075 {
1076 	struct device *dev = di->dev;
1077 	struct bq27xxx_platform_data *pdata = dev->platform_data;
1078 	unsigned int timeout = 3;
1079 	int upper, lower;
1080 	int temp;
1081 
1082 	if (!single) {
1083 		/* Make sure the value has not changed in between reading the
1084 		 * lower and the upper part */
1085 		upper = pdata->read(dev, reg + 1);
1086 		do {
1087 			temp = upper;
1088 			if (upper < 0)
1089 				return upper;
1090 
1091 			lower = pdata->read(dev, reg);
1092 			if (lower < 0)
1093 				return lower;
1094 
1095 			upper = pdata->read(dev, reg + 1);
1096 		} while (temp != upper && --timeout);
1097 
1098 		if (timeout == 0)
1099 			return -EIO;
1100 
1101 		return (upper << 8) | lower;
1102 	}
1103 
1104 	return pdata->read(dev, reg);
1105 }
1106 
1107 static int bq27xxx_battery_platform_probe(struct platform_device *pdev)
1108 {
1109 	struct bq27xxx_device_info *di;
1110 	struct bq27xxx_platform_data *pdata = pdev->dev.platform_data;
1111 
1112 	if (!pdata) {
1113 		dev_err(&pdev->dev, "no platform_data supplied\n");
1114 		return -EINVAL;
1115 	}
1116 
1117 	if (!pdata->read) {
1118 		dev_err(&pdev->dev, "no hdq read callback supplied\n");
1119 		return -EINVAL;
1120 	}
1121 
1122 	if (!pdata->chip) {
1123 		dev_err(&pdev->dev, "no device supplied\n");
1124 		return -EINVAL;
1125 	}
1126 
1127 	di = devm_kzalloc(&pdev->dev, sizeof(*di), GFP_KERNEL);
1128 	if (!di)
1129 		return -ENOMEM;
1130 
1131 	platform_set_drvdata(pdev, di);
1132 
1133 	di->dev = &pdev->dev;
1134 	di->chip = pdata->chip;
1135 	di->name = pdata->name ?: dev_name(&pdev->dev);
1136 	di->bus.read = bq27xxx_battery_platform_read;
1137 
1138 	return bq27xxx_battery_setup(di);
1139 }
1140 
1141 static int bq27xxx_battery_platform_remove(struct platform_device *pdev)
1142 {
1143 	struct bq27xxx_device_info *di = platform_get_drvdata(pdev);
1144 
1145 	bq27xxx_battery_teardown(di);
1146 
1147 	return 0;
1148 }
1149 
1150 static const struct platform_device_id bq27xxx_battery_platform_id_table[] = {
1151 	{ "bq27000-battery", },
1152 	{ /* sentinel */ }
1153 };
1154 MODULE_DEVICE_TABLE(platform, bq27xxx_battery_platform_id_table);
1155 
1156 #ifdef CONFIG_OF
1157 static const struct of_device_id bq27xxx_battery_platform_of_match_table[] = {
1158 	{ .compatible = "ti,bq27000" },
1159 	{},
1160 };
1161 MODULE_DEVICE_TABLE(of, bq27xxx_battery_platform_of_match_table);
1162 #endif
1163 
1164 static struct platform_driver bq27xxx_battery_platform_driver = {
1165 	.probe	= bq27xxx_battery_platform_probe,
1166 	.remove = bq27xxx_battery_platform_remove,
1167 	.driver = {
1168 		.name = "bq27000-battery",
1169 		.of_match_table = of_match_ptr(bq27xxx_battery_platform_of_match_table),
1170 	},
1171 	.id_table = bq27xxx_battery_platform_id_table,
1172 };
1173 module_platform_driver(bq27xxx_battery_platform_driver);
1174 
1175 MODULE_ALIAS("platform:bq27000-battery");
1176 
1177 MODULE_AUTHOR("Rodolfo Giometti <giometti@linux.it>");
1178 MODULE_DESCRIPTION("BQ27xxx battery monitor driver");
1179 MODULE_LICENSE("GPL");
1180