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 	[BQ27530] = {
168 		[BQ27XXX_REG_CTRL] = 0x00,
169 		[BQ27XXX_REG_TEMP] = 0x06,
170 		[BQ27XXX_REG_INT_TEMP] = 0x32,
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] = INVALID_REG_ADDR,
177 		[BQ27XXX_REG_TTECP] = INVALID_REG_ADDR,
178 		[BQ27XXX_REG_NAC] = 0x0c,
179 		[BQ27XXX_REG_FCC] = 0x12,
180 		[BQ27XXX_REG_CYCT] = 0x2a,
181 		[BQ27XXX_REG_AE] = INVALID_REG_ADDR,
182 		[BQ27XXX_REG_SOC] = 0x2c,
183 		[BQ27XXX_REG_DCAP] = INVALID_REG_ADDR,
184 		[BQ27XXX_REG_AP] = 0x24,
185 	},
186 	[BQ27541] = {
187 		[BQ27XXX_REG_CTRL] = 0x00,
188 		[BQ27XXX_REG_TEMP] = 0x06,
189 		[BQ27XXX_REG_INT_TEMP] = 0x28,
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] = 0x3c,
203 		[BQ27XXX_REG_AP] = 0x24,
204 	},
205 	[BQ27545] = {
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] = INVALID_REG_ADDR,
222 		[BQ27XXX_REG_AP] = 0x24,
223 	},
224 	[BQ27421] = {
225 		[BQ27XXX_REG_CTRL] = 0x00,
226 		[BQ27XXX_REG_TEMP] = 0x02,
227 		[BQ27XXX_REG_INT_TEMP] = 0x1e,
228 		[BQ27XXX_REG_VOLT] = 0x04,
229 		[BQ27XXX_REG_AI] = 0x10,
230 		[BQ27XXX_REG_FLAGS] = 0x06,
231 		[BQ27XXX_REG_TTE] = INVALID_REG_ADDR,
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] = 0x08,
236 		[BQ27XXX_REG_FCC] = 0x0e,
237 		[BQ27XXX_REG_CYCT] = INVALID_REG_ADDR,
238 		[BQ27XXX_REG_AE] = INVALID_REG_ADDR,
239 		[BQ27XXX_REG_SOC] = 0x1c,
240 		[BQ27XXX_REG_DCAP] = 0x3c,
241 		[BQ27XXX_REG_AP] = 0x18,
242 	},
243 };
244 
245 static enum power_supply_property bq27000_battery_props[] = {
246 	POWER_SUPPLY_PROP_STATUS,
247 	POWER_SUPPLY_PROP_PRESENT,
248 	POWER_SUPPLY_PROP_VOLTAGE_NOW,
249 	POWER_SUPPLY_PROP_CURRENT_NOW,
250 	POWER_SUPPLY_PROP_CAPACITY,
251 	POWER_SUPPLY_PROP_CAPACITY_LEVEL,
252 	POWER_SUPPLY_PROP_TEMP,
253 	POWER_SUPPLY_PROP_TIME_TO_EMPTY_NOW,
254 	POWER_SUPPLY_PROP_TIME_TO_EMPTY_AVG,
255 	POWER_SUPPLY_PROP_TIME_TO_FULL_NOW,
256 	POWER_SUPPLY_PROP_TECHNOLOGY,
257 	POWER_SUPPLY_PROP_CHARGE_FULL,
258 	POWER_SUPPLY_PROP_CHARGE_NOW,
259 	POWER_SUPPLY_PROP_CHARGE_FULL_DESIGN,
260 	POWER_SUPPLY_PROP_CYCLE_COUNT,
261 	POWER_SUPPLY_PROP_ENERGY_NOW,
262 	POWER_SUPPLY_PROP_POWER_AVG,
263 	POWER_SUPPLY_PROP_HEALTH,
264 	POWER_SUPPLY_PROP_MANUFACTURER,
265 };
266 
267 static enum power_supply_property bq27010_battery_props[] = {
268 	POWER_SUPPLY_PROP_STATUS,
269 	POWER_SUPPLY_PROP_PRESENT,
270 	POWER_SUPPLY_PROP_VOLTAGE_NOW,
271 	POWER_SUPPLY_PROP_CURRENT_NOW,
272 	POWER_SUPPLY_PROP_CAPACITY,
273 	POWER_SUPPLY_PROP_CAPACITY_LEVEL,
274 	POWER_SUPPLY_PROP_TEMP,
275 	POWER_SUPPLY_PROP_TIME_TO_EMPTY_NOW,
276 	POWER_SUPPLY_PROP_TIME_TO_EMPTY_AVG,
277 	POWER_SUPPLY_PROP_TIME_TO_FULL_NOW,
278 	POWER_SUPPLY_PROP_TECHNOLOGY,
279 	POWER_SUPPLY_PROP_CHARGE_FULL,
280 	POWER_SUPPLY_PROP_CHARGE_NOW,
281 	POWER_SUPPLY_PROP_CHARGE_FULL_DESIGN,
282 	POWER_SUPPLY_PROP_CYCLE_COUNT,
283 	POWER_SUPPLY_PROP_HEALTH,
284 	POWER_SUPPLY_PROP_MANUFACTURER,
285 };
286 
287 static enum power_supply_property bq27500_battery_props[] = {
288 	POWER_SUPPLY_PROP_STATUS,
289 	POWER_SUPPLY_PROP_PRESENT,
290 	POWER_SUPPLY_PROP_VOLTAGE_NOW,
291 	POWER_SUPPLY_PROP_CURRENT_NOW,
292 	POWER_SUPPLY_PROP_CAPACITY,
293 	POWER_SUPPLY_PROP_CAPACITY_LEVEL,
294 	POWER_SUPPLY_PROP_TEMP,
295 	POWER_SUPPLY_PROP_TIME_TO_EMPTY_NOW,
296 	POWER_SUPPLY_PROP_TECHNOLOGY,
297 	POWER_SUPPLY_PROP_CHARGE_FULL,
298 	POWER_SUPPLY_PROP_CHARGE_NOW,
299 	POWER_SUPPLY_PROP_CHARGE_FULL_DESIGN,
300 	POWER_SUPPLY_PROP_CYCLE_COUNT,
301 	POWER_SUPPLY_PROP_HEALTH,
302 	POWER_SUPPLY_PROP_MANUFACTURER,
303 };
304 
305 static enum power_supply_property bq27530_battery_props[] = {
306 	POWER_SUPPLY_PROP_STATUS,
307 	POWER_SUPPLY_PROP_PRESENT,
308 	POWER_SUPPLY_PROP_VOLTAGE_NOW,
309 	POWER_SUPPLY_PROP_CURRENT_NOW,
310 	POWER_SUPPLY_PROP_CAPACITY,
311 	POWER_SUPPLY_PROP_CAPACITY_LEVEL,
312 	POWER_SUPPLY_PROP_TEMP,
313 	POWER_SUPPLY_PROP_TIME_TO_EMPTY_NOW,
314 	POWER_SUPPLY_PROP_TECHNOLOGY,
315 	POWER_SUPPLY_PROP_CHARGE_FULL,
316 	POWER_SUPPLY_PROP_CHARGE_NOW,
317 	POWER_SUPPLY_PROP_POWER_AVG,
318 	POWER_SUPPLY_PROP_HEALTH,
319 	POWER_SUPPLY_PROP_CYCLE_COUNT,
320 	POWER_SUPPLY_PROP_MANUFACTURER,
321 };
322 
323 static enum power_supply_property bq27541_battery_props[] = {
324 	POWER_SUPPLY_PROP_STATUS,
325 	POWER_SUPPLY_PROP_PRESENT,
326 	POWER_SUPPLY_PROP_VOLTAGE_NOW,
327 	POWER_SUPPLY_PROP_CURRENT_NOW,
328 	POWER_SUPPLY_PROP_CAPACITY,
329 	POWER_SUPPLY_PROP_CAPACITY_LEVEL,
330 	POWER_SUPPLY_PROP_TEMP,
331 	POWER_SUPPLY_PROP_TIME_TO_EMPTY_NOW,
332 	POWER_SUPPLY_PROP_TECHNOLOGY,
333 	POWER_SUPPLY_PROP_CHARGE_FULL,
334 	POWER_SUPPLY_PROP_CHARGE_NOW,
335 	POWER_SUPPLY_PROP_CHARGE_FULL_DESIGN,
336 	POWER_SUPPLY_PROP_CYCLE_COUNT,
337 	POWER_SUPPLY_PROP_POWER_AVG,
338 	POWER_SUPPLY_PROP_HEALTH,
339 	POWER_SUPPLY_PROP_MANUFACTURER,
340 };
341 
342 static enum power_supply_property bq27545_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_HEALTH,
355 	POWER_SUPPLY_PROP_CYCLE_COUNT,
356 	POWER_SUPPLY_PROP_POWER_AVG,
357 	POWER_SUPPLY_PROP_MANUFACTURER,
358 };
359 
360 static enum power_supply_property bq27421_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_TECHNOLOGY,
369 	POWER_SUPPLY_PROP_CHARGE_FULL,
370 	POWER_SUPPLY_PROP_CHARGE_NOW,
371 	POWER_SUPPLY_PROP_CHARGE_FULL_DESIGN,
372 	POWER_SUPPLY_PROP_MANUFACTURER,
373 };
374 
375 #define BQ27XXX_PROP(_id, _prop)		\
376 	[_id] = {				\
377 		.props = _prop,			\
378 		.size = ARRAY_SIZE(_prop),	\
379 	}
380 
381 static struct {
382 	enum power_supply_property *props;
383 	size_t size;
384 } bq27xxx_battery_props[] = {
385 	BQ27XXX_PROP(BQ27000, bq27000_battery_props),
386 	BQ27XXX_PROP(BQ27010, bq27010_battery_props),
387 	BQ27XXX_PROP(BQ27500, bq27500_battery_props),
388 	BQ27XXX_PROP(BQ27530, bq27530_battery_props),
389 	BQ27XXX_PROP(BQ27541, bq27541_battery_props),
390 	BQ27XXX_PROP(BQ27545, bq27545_battery_props),
391 	BQ27XXX_PROP(BQ27421, bq27421_battery_props),
392 };
393 
394 static DEFINE_MUTEX(bq27xxx_list_lock);
395 static LIST_HEAD(bq27xxx_battery_devices);
396 
397 static int poll_interval_param_set(const char *val, const struct kernel_param *kp)
398 {
399 	struct bq27xxx_device_info *di;
400 	int ret;
401 
402 	ret = param_set_uint(val, kp);
403 	if (ret < 0)
404 		return ret;
405 
406 	mutex_lock(&bq27xxx_list_lock);
407 	list_for_each_entry(di, &bq27xxx_battery_devices, list) {
408 		cancel_delayed_work_sync(&di->work);
409 		schedule_delayed_work(&di->work, 0);
410 	}
411 	mutex_unlock(&bq27xxx_list_lock);
412 
413 	return ret;
414 }
415 
416 static const struct kernel_param_ops param_ops_poll_interval = {
417 	.get = param_get_uint,
418 	.set = poll_interval_param_set,
419 };
420 
421 static unsigned int poll_interval = 360;
422 module_param_cb(poll_interval, &param_ops_poll_interval, &poll_interval, 0644);
423 MODULE_PARM_DESC(poll_interval,
424 		 "battery poll interval in seconds - 0 disables polling");
425 
426 /*
427  * Common code for BQ27xxx devices
428  */
429 
430 static inline int bq27xxx_read(struct bq27xxx_device_info *di, int reg_index,
431 			       bool single)
432 {
433 	/* Reports EINVAL for invalid/missing registers */
434 	if (!di || di->regs[reg_index] == INVALID_REG_ADDR)
435 		return -EINVAL;
436 
437 	return di->bus.read(di, di->regs[reg_index], single);
438 }
439 
440 /*
441  * Return the battery State-of-Charge
442  * Or < 0 if something fails.
443  */
444 static int bq27xxx_battery_read_soc(struct bq27xxx_device_info *di)
445 {
446 	int soc;
447 
448 	if (di->chip == BQ27000 || di->chip == BQ27010)
449 		soc = bq27xxx_read(di, BQ27XXX_REG_SOC, true);
450 	else
451 		soc = bq27xxx_read(di, BQ27XXX_REG_SOC, false);
452 
453 	if (soc < 0)
454 		dev_dbg(di->dev, "error reading State-of-Charge\n");
455 
456 	return soc;
457 }
458 
459 /*
460  * Return a battery charge value in µAh
461  * Or < 0 if something fails.
462  */
463 static int bq27xxx_battery_read_charge(struct bq27xxx_device_info *di, u8 reg)
464 {
465 	int charge;
466 
467 	charge = bq27xxx_read(di, reg, false);
468 	if (charge < 0) {
469 		dev_dbg(di->dev, "error reading charge register %02x: %d\n",
470 			reg, charge);
471 		return charge;
472 	}
473 
474 	if (di->chip == BQ27000 || di->chip == BQ27010)
475 		charge *= BQ27XXX_CURRENT_CONSTANT / BQ27XXX_RS;
476 	else
477 		charge *= 1000;
478 
479 	return charge;
480 }
481 
482 /*
483  * Return the battery Nominal available capacity in µAh
484  * Or < 0 if something fails.
485  */
486 static inline int bq27xxx_battery_read_nac(struct bq27xxx_device_info *di)
487 {
488 	int flags;
489 
490 	if (di->chip == BQ27000 || di->chip == BQ27010) {
491 		flags = bq27xxx_read(di, BQ27XXX_REG_FLAGS, true);
492 		if (flags >= 0 && (flags & BQ27000_FLAG_CI))
493 			return -ENODATA;
494 	}
495 
496 	return bq27xxx_battery_read_charge(di, BQ27XXX_REG_NAC);
497 }
498 
499 /*
500  * Return the battery Full Charge Capacity in µAh
501  * Or < 0 if something fails.
502  */
503 static inline int bq27xxx_battery_read_fcc(struct bq27xxx_device_info *di)
504 {
505 	return bq27xxx_battery_read_charge(di, BQ27XXX_REG_FCC);
506 }
507 
508 /*
509  * Return the Design Capacity in µAh
510  * Or < 0 if something fails.
511  */
512 static int bq27xxx_battery_read_dcap(struct bq27xxx_device_info *di)
513 {
514 	int dcap;
515 
516 	if (di->chip == BQ27000 || di->chip == BQ27010)
517 		dcap = bq27xxx_read(di, BQ27XXX_REG_DCAP, true);
518 	else
519 		dcap = bq27xxx_read(di, BQ27XXX_REG_DCAP, false);
520 
521 	if (dcap < 0) {
522 		dev_dbg(di->dev, "error reading initial last measured discharge\n");
523 		return dcap;
524 	}
525 
526 	if (di->chip == BQ27000 || di->chip == BQ27010)
527 		dcap = (dcap << 8) * BQ27XXX_CURRENT_CONSTANT / BQ27XXX_RS;
528 	else
529 		dcap *= 1000;
530 
531 	return dcap;
532 }
533 
534 /*
535  * Return the battery Available energy in µWh
536  * Or < 0 if something fails.
537  */
538 static int bq27xxx_battery_read_energy(struct bq27xxx_device_info *di)
539 {
540 	int ae;
541 
542 	ae = bq27xxx_read(di, BQ27XXX_REG_AE, false);
543 	if (ae < 0) {
544 		dev_dbg(di->dev, "error reading available energy\n");
545 		return ae;
546 	}
547 
548 	if (di->chip == BQ27000 || di->chip == BQ27010)
549 		ae *= BQ27XXX_POWER_CONSTANT / BQ27XXX_RS;
550 	else
551 		ae *= 1000;
552 
553 	return ae;
554 }
555 
556 /*
557  * Return the battery temperature in tenths of degree Kelvin
558  * Or < 0 if something fails.
559  */
560 static int bq27xxx_battery_read_temperature(struct bq27xxx_device_info *di)
561 {
562 	int temp;
563 
564 	temp = bq27xxx_read(di, BQ27XXX_REG_TEMP, false);
565 	if (temp < 0) {
566 		dev_err(di->dev, "error reading temperature\n");
567 		return temp;
568 	}
569 
570 	if (di->chip == BQ27000 || di->chip == BQ27010)
571 		temp = 5 * temp / 2;
572 
573 	return temp;
574 }
575 
576 /*
577  * Return the battery Cycle count total
578  * Or < 0 if something fails.
579  */
580 static int bq27xxx_battery_read_cyct(struct bq27xxx_device_info *di)
581 {
582 	int cyct;
583 
584 	cyct = bq27xxx_read(di, BQ27XXX_REG_CYCT, false);
585 	if (cyct < 0)
586 		dev_err(di->dev, "error reading cycle count total\n");
587 
588 	return cyct;
589 }
590 
591 /*
592  * Read a time register.
593  * Return < 0 if something fails.
594  */
595 static int bq27xxx_battery_read_time(struct bq27xxx_device_info *di, u8 reg)
596 {
597 	int tval;
598 
599 	tval = bq27xxx_read(di, reg, false);
600 	if (tval < 0) {
601 		dev_dbg(di->dev, "error reading time register %02x: %d\n",
602 			reg, tval);
603 		return tval;
604 	}
605 
606 	if (tval == 65535)
607 		return -ENODATA;
608 
609 	return tval * 60;
610 }
611 
612 /*
613  * Read an average power register.
614  * Return < 0 if something fails.
615  */
616 static int bq27xxx_battery_read_pwr_avg(struct bq27xxx_device_info *di)
617 {
618 	int tval;
619 
620 	tval = bq27xxx_read(di, BQ27XXX_REG_AP, false);
621 	if (tval < 0) {
622 		dev_err(di->dev, "error reading average power register  %02x: %d\n",
623 			BQ27XXX_REG_AP, tval);
624 		return tval;
625 	}
626 
627 	if (di->chip == BQ27000 || di->chip == BQ27010)
628 		return (tval * BQ27XXX_POWER_CONSTANT) / BQ27XXX_RS;
629 	else
630 		return tval;
631 }
632 
633 /*
634  * Returns true if a battery over temperature condition is detected
635  */
636 static bool bq27xxx_battery_overtemp(struct bq27xxx_device_info *di, u16 flags)
637 {
638 	if (di->chip == BQ27500 || di->chip == BQ27541 || di->chip == BQ27545)
639 		return flags & (BQ27XXX_FLAG_OTC | BQ27XXX_FLAG_OTD);
640 	if (di->chip == BQ27530 || di->chip == BQ27421)
641 		return flags & BQ27XXX_FLAG_OT;
642 
643 	return false;
644 }
645 
646 /*
647  * Returns true if a battery under temperature condition is detected
648  */
649 static bool bq27xxx_battery_undertemp(struct bq27xxx_device_info *di, u16 flags)
650 {
651 	if (di->chip == BQ27530 || di->chip == BQ27421)
652 		return flags & BQ27XXX_FLAG_UT;
653 
654 	return false;
655 }
656 
657 /*
658  * Returns true if a low state of charge condition is detected
659  */
660 static bool bq27xxx_battery_dead(struct bq27xxx_device_info *di, u16 flags)
661 {
662 	if (di->chip == BQ27000 || di->chip == BQ27010)
663 		return flags & (BQ27000_FLAG_EDV1 | BQ27000_FLAG_EDVF);
664 	else
665 		return flags & (BQ27XXX_FLAG_SOC1 | BQ27XXX_FLAG_SOCF);
666 }
667 
668 /*
669  * Read flag register.
670  * Return < 0 if something fails.
671  */
672 static int bq27xxx_battery_read_health(struct bq27xxx_device_info *di)
673 {
674 	int flags;
675 	bool has_singe_flag = di->chip == BQ27000 || di->chip == BQ27010;
676 
677 	flags = bq27xxx_read(di, BQ27XXX_REG_FLAGS, has_singe_flag);
678 	if (flags < 0) {
679 		dev_err(di->dev, "error reading flag register:%d\n", flags);
680 		return flags;
681 	}
682 
683 	/* Unlikely but important to return first */
684 	if (unlikely(bq27xxx_battery_overtemp(di, flags)))
685 		return POWER_SUPPLY_HEALTH_OVERHEAT;
686 	if (unlikely(bq27xxx_battery_undertemp(di, flags)))
687 		return POWER_SUPPLY_HEALTH_COLD;
688 	if (unlikely(bq27xxx_battery_dead(di, flags)))
689 		return POWER_SUPPLY_HEALTH_DEAD;
690 
691 	return POWER_SUPPLY_HEALTH_GOOD;
692 }
693 
694 void bq27xxx_battery_update(struct bq27xxx_device_info *di)
695 {
696 	struct bq27xxx_reg_cache cache = {0, };
697 	bool has_ci_flag = di->chip == BQ27000 || di->chip == BQ27010;
698 	bool has_singe_flag = di->chip == BQ27000 || di->chip == BQ27010;
699 
700 	cache.flags = bq27xxx_read(di, BQ27XXX_REG_FLAGS, has_singe_flag);
701 	if ((cache.flags & 0xff) == 0xff)
702 		cache.flags = -1; /* read error */
703 	if (cache.flags >= 0) {
704 		cache.temperature = bq27xxx_battery_read_temperature(di);
705 		if (has_ci_flag && (cache.flags & BQ27000_FLAG_CI)) {
706 			dev_info_once(di->dev, "battery is not calibrated! ignoring capacity values\n");
707 			cache.capacity = -ENODATA;
708 			cache.energy = -ENODATA;
709 			cache.time_to_empty = -ENODATA;
710 			cache.time_to_empty_avg = -ENODATA;
711 			cache.time_to_full = -ENODATA;
712 			cache.charge_full = -ENODATA;
713 			cache.health = -ENODATA;
714 		} else {
715 			if (di->regs[BQ27XXX_REG_TTE] != INVALID_REG_ADDR)
716 				cache.time_to_empty = bq27xxx_battery_read_time(di, BQ27XXX_REG_TTE);
717 			if (di->regs[BQ27XXX_REG_TTECP] != INVALID_REG_ADDR)
718 				cache.time_to_empty_avg = bq27xxx_battery_read_time(di, BQ27XXX_REG_TTECP);
719 			if (di->regs[BQ27XXX_REG_TTF] != INVALID_REG_ADDR)
720 				cache.time_to_full = bq27xxx_battery_read_time(di, BQ27XXX_REG_TTF);
721 			cache.charge_full = bq27xxx_battery_read_fcc(di);
722 			cache.capacity = bq27xxx_battery_read_soc(di);
723 			if (di->regs[BQ27XXX_REG_AE] != INVALID_REG_ADDR)
724 				cache.energy = bq27xxx_battery_read_energy(di);
725 			cache.health = bq27xxx_battery_read_health(di);
726 		}
727 		if (di->regs[BQ27XXX_REG_CYCT] != INVALID_REG_ADDR)
728 			cache.cycle_count = bq27xxx_battery_read_cyct(di);
729 		if (di->regs[BQ27XXX_REG_AP] != INVALID_REG_ADDR)
730 			cache.power_avg = bq27xxx_battery_read_pwr_avg(di);
731 
732 		/* We only have to read charge design full once */
733 		if (di->charge_design_full <= 0)
734 			di->charge_design_full = bq27xxx_battery_read_dcap(di);
735 	}
736 
737 	if (di->cache.capacity != cache.capacity)
738 		power_supply_changed(di->bat);
739 
740 	if (memcmp(&di->cache, &cache, sizeof(cache)) != 0)
741 		di->cache = cache;
742 
743 	di->last_update = jiffies;
744 }
745 EXPORT_SYMBOL_GPL(bq27xxx_battery_update);
746 
747 static void bq27xxx_battery_poll(struct work_struct *work)
748 {
749 	struct bq27xxx_device_info *di =
750 			container_of(work, struct bq27xxx_device_info,
751 				     work.work);
752 
753 	bq27xxx_battery_update(di);
754 
755 	if (poll_interval > 0)
756 		schedule_delayed_work(&di->work, poll_interval * HZ);
757 }
758 
759 /*
760  * Return the battery average current in µA
761  * Note that current can be negative signed as well
762  * Or 0 if something fails.
763  */
764 static int bq27xxx_battery_current(struct bq27xxx_device_info *di,
765 				   union power_supply_propval *val)
766 {
767 	int curr;
768 	int flags;
769 
770 	curr = bq27xxx_read(di, BQ27XXX_REG_AI, false);
771 	if (curr < 0) {
772 		dev_err(di->dev, "error reading current\n");
773 		return curr;
774 	}
775 
776 	if (di->chip == BQ27000 || di->chip == BQ27010) {
777 		flags = bq27xxx_read(di, BQ27XXX_REG_FLAGS, true);
778 		if (flags & BQ27000_FLAG_CHGS) {
779 			dev_dbg(di->dev, "negative current!\n");
780 			curr = -curr;
781 		}
782 
783 		val->intval = curr * BQ27XXX_CURRENT_CONSTANT / BQ27XXX_RS;
784 	} else {
785 		/* Other gauges return signed value */
786 		val->intval = (int)((s16)curr) * 1000;
787 	}
788 
789 	return 0;
790 }
791 
792 static int bq27xxx_battery_status(struct bq27xxx_device_info *di,
793 				  union power_supply_propval *val)
794 {
795 	int status;
796 
797 	if (di->chip == BQ27000 || di->chip == BQ27010) {
798 		if (di->cache.flags & BQ27000_FLAG_FC)
799 			status = POWER_SUPPLY_STATUS_FULL;
800 		else if (di->cache.flags & BQ27000_FLAG_CHGS)
801 			status = POWER_SUPPLY_STATUS_CHARGING;
802 		else if (power_supply_am_i_supplied(di->bat))
803 			status = POWER_SUPPLY_STATUS_NOT_CHARGING;
804 		else
805 			status = POWER_SUPPLY_STATUS_DISCHARGING;
806 	} else {
807 		if (di->cache.flags & BQ27XXX_FLAG_FC)
808 			status = POWER_SUPPLY_STATUS_FULL;
809 		else if (di->cache.flags & BQ27XXX_FLAG_DSC)
810 			status = POWER_SUPPLY_STATUS_DISCHARGING;
811 		else
812 			status = POWER_SUPPLY_STATUS_CHARGING;
813 	}
814 
815 	val->intval = status;
816 
817 	return 0;
818 }
819 
820 static int bq27xxx_battery_capacity_level(struct bq27xxx_device_info *di,
821 					  union power_supply_propval *val)
822 {
823 	int level;
824 
825 	if (di->chip == BQ27000 || di->chip == BQ27010) {
826 		if (di->cache.flags & BQ27000_FLAG_FC)
827 			level = POWER_SUPPLY_CAPACITY_LEVEL_FULL;
828 		else if (di->cache.flags & BQ27000_FLAG_EDV1)
829 			level = POWER_SUPPLY_CAPACITY_LEVEL_LOW;
830 		else if (di->cache.flags & BQ27000_FLAG_EDVF)
831 			level = POWER_SUPPLY_CAPACITY_LEVEL_CRITICAL;
832 		else
833 			level = POWER_SUPPLY_CAPACITY_LEVEL_NORMAL;
834 	} else {
835 		if (di->cache.flags & BQ27XXX_FLAG_FC)
836 			level = POWER_SUPPLY_CAPACITY_LEVEL_FULL;
837 		else if (di->cache.flags & BQ27XXX_FLAG_SOC1)
838 			level = POWER_SUPPLY_CAPACITY_LEVEL_LOW;
839 		else if (di->cache.flags & BQ27XXX_FLAG_SOCF)
840 			level = POWER_SUPPLY_CAPACITY_LEVEL_CRITICAL;
841 		else
842 			level = POWER_SUPPLY_CAPACITY_LEVEL_NORMAL;
843 	}
844 
845 	val->intval = level;
846 
847 	return 0;
848 }
849 
850 /*
851  * Return the battery Voltage in millivolts
852  * Or < 0 if something fails.
853  */
854 static int bq27xxx_battery_voltage(struct bq27xxx_device_info *di,
855 				   union power_supply_propval *val)
856 {
857 	int volt;
858 
859 	volt = bq27xxx_read(di, BQ27XXX_REG_VOLT, false);
860 	if (volt < 0) {
861 		dev_err(di->dev, "error reading voltage\n");
862 		return volt;
863 	}
864 
865 	val->intval = volt * 1000;
866 
867 	return 0;
868 }
869 
870 static int bq27xxx_simple_value(int value,
871 				union power_supply_propval *val)
872 {
873 	if (value < 0)
874 		return value;
875 
876 	val->intval = value;
877 
878 	return 0;
879 }
880 
881 static int bq27xxx_battery_get_property(struct power_supply *psy,
882 					enum power_supply_property psp,
883 					union power_supply_propval *val)
884 {
885 	int ret = 0;
886 	struct bq27xxx_device_info *di = power_supply_get_drvdata(psy);
887 
888 	mutex_lock(&di->lock);
889 	if (time_is_before_jiffies(di->last_update + 5 * HZ)) {
890 		cancel_delayed_work_sync(&di->work);
891 		bq27xxx_battery_poll(&di->work.work);
892 	}
893 	mutex_unlock(&di->lock);
894 
895 	if (psp != POWER_SUPPLY_PROP_PRESENT && di->cache.flags < 0)
896 		return -ENODEV;
897 
898 	switch (psp) {
899 	case POWER_SUPPLY_PROP_STATUS:
900 		ret = bq27xxx_battery_status(di, val);
901 		break;
902 	case POWER_SUPPLY_PROP_VOLTAGE_NOW:
903 		ret = bq27xxx_battery_voltage(di, val);
904 		break;
905 	case POWER_SUPPLY_PROP_PRESENT:
906 		val->intval = di->cache.flags < 0 ? 0 : 1;
907 		break;
908 	case POWER_SUPPLY_PROP_CURRENT_NOW:
909 		ret = bq27xxx_battery_current(di, val);
910 		break;
911 	case POWER_SUPPLY_PROP_CAPACITY:
912 		ret = bq27xxx_simple_value(di->cache.capacity, val);
913 		break;
914 	case POWER_SUPPLY_PROP_CAPACITY_LEVEL:
915 		ret = bq27xxx_battery_capacity_level(di, val);
916 		break;
917 	case POWER_SUPPLY_PROP_TEMP:
918 		ret = bq27xxx_simple_value(di->cache.temperature, val);
919 		if (ret == 0)
920 			val->intval -= 2731; /* convert decidegree k to c */
921 		break;
922 	case POWER_SUPPLY_PROP_TIME_TO_EMPTY_NOW:
923 		ret = bq27xxx_simple_value(di->cache.time_to_empty, val);
924 		break;
925 	case POWER_SUPPLY_PROP_TIME_TO_EMPTY_AVG:
926 		ret = bq27xxx_simple_value(di->cache.time_to_empty_avg, val);
927 		break;
928 	case POWER_SUPPLY_PROP_TIME_TO_FULL_NOW:
929 		ret = bq27xxx_simple_value(di->cache.time_to_full, val);
930 		break;
931 	case POWER_SUPPLY_PROP_TECHNOLOGY:
932 		val->intval = POWER_SUPPLY_TECHNOLOGY_LION;
933 		break;
934 	case POWER_SUPPLY_PROP_CHARGE_NOW:
935 		ret = bq27xxx_simple_value(bq27xxx_battery_read_nac(di), val);
936 		break;
937 	case POWER_SUPPLY_PROP_CHARGE_FULL:
938 		ret = bq27xxx_simple_value(di->cache.charge_full, val);
939 		break;
940 	case POWER_SUPPLY_PROP_CHARGE_FULL_DESIGN:
941 		ret = bq27xxx_simple_value(di->charge_design_full, val);
942 		break;
943 	case POWER_SUPPLY_PROP_CYCLE_COUNT:
944 		ret = bq27xxx_simple_value(di->cache.cycle_count, val);
945 		break;
946 	case POWER_SUPPLY_PROP_ENERGY_NOW:
947 		ret = bq27xxx_simple_value(di->cache.energy, val);
948 		break;
949 	case POWER_SUPPLY_PROP_POWER_AVG:
950 		ret = bq27xxx_simple_value(di->cache.power_avg, val);
951 		break;
952 	case POWER_SUPPLY_PROP_HEALTH:
953 		ret = bq27xxx_simple_value(di->cache.health, val);
954 		break;
955 	case POWER_SUPPLY_PROP_MANUFACTURER:
956 		val->strval = BQ27XXX_MANUFACTURER;
957 		break;
958 	default:
959 		return -EINVAL;
960 	}
961 
962 	return ret;
963 }
964 
965 static void bq27xxx_external_power_changed(struct power_supply *psy)
966 {
967 	struct bq27xxx_device_info *di = power_supply_get_drvdata(psy);
968 
969 	cancel_delayed_work_sync(&di->work);
970 	schedule_delayed_work(&di->work, 0);
971 }
972 
973 int bq27xxx_battery_setup(struct bq27xxx_device_info *di)
974 {
975 	struct power_supply_desc *psy_desc;
976 	struct power_supply_config psy_cfg = { .drv_data = di, };
977 
978 	INIT_DELAYED_WORK(&di->work, bq27xxx_battery_poll);
979 	mutex_init(&di->lock);
980 	di->regs = bq27xxx_regs[di->chip];
981 
982 	psy_desc = devm_kzalloc(di->dev, sizeof(*psy_desc), GFP_KERNEL);
983 	if (!psy_desc)
984 		return -ENOMEM;
985 
986 	psy_desc->name = di->name;
987 	psy_desc->type = POWER_SUPPLY_TYPE_BATTERY;
988 	psy_desc->properties = bq27xxx_battery_props[di->chip].props;
989 	psy_desc->num_properties = bq27xxx_battery_props[di->chip].size;
990 	psy_desc->get_property = bq27xxx_battery_get_property;
991 	psy_desc->external_power_changed = bq27xxx_external_power_changed;
992 
993 	di->bat = power_supply_register_no_ws(di->dev, psy_desc, &psy_cfg);
994 	if (IS_ERR(di->bat)) {
995 		dev_err(di->dev, "failed to register battery\n");
996 		return PTR_ERR(di->bat);
997 	}
998 
999 	dev_info(di->dev, "support ver. %s enabled\n", DRIVER_VERSION);
1000 
1001 	bq27xxx_battery_update(di);
1002 
1003 	mutex_lock(&bq27xxx_list_lock);
1004 	list_add(&di->list, &bq27xxx_battery_devices);
1005 	mutex_unlock(&bq27xxx_list_lock);
1006 
1007 	return 0;
1008 }
1009 EXPORT_SYMBOL_GPL(bq27xxx_battery_setup);
1010 
1011 void bq27xxx_battery_teardown(struct bq27xxx_device_info *di)
1012 {
1013 	/*
1014 	 * power_supply_unregister call bq27xxx_battery_get_property which
1015 	 * call bq27xxx_battery_poll.
1016 	 * Make sure that bq27xxx_battery_poll will not call
1017 	 * schedule_delayed_work again after unregister (which cause OOPS).
1018 	 */
1019 	poll_interval = 0;
1020 
1021 	cancel_delayed_work_sync(&di->work);
1022 
1023 	power_supply_unregister(di->bat);
1024 
1025 	mutex_lock(&bq27xxx_list_lock);
1026 	list_del(&di->list);
1027 	mutex_unlock(&bq27xxx_list_lock);
1028 
1029 	mutex_destroy(&di->lock);
1030 }
1031 EXPORT_SYMBOL_GPL(bq27xxx_battery_teardown);
1032 
1033 static int bq27xxx_battery_platform_read(struct bq27xxx_device_info *di, u8 reg,
1034 					 bool single)
1035 {
1036 	struct device *dev = di->dev;
1037 	struct bq27xxx_platform_data *pdata = dev->platform_data;
1038 	unsigned int timeout = 3;
1039 	int upper, lower;
1040 	int temp;
1041 
1042 	if (!single) {
1043 		/* Make sure the value has not changed in between reading the
1044 		 * lower and the upper part */
1045 		upper = pdata->read(dev, reg + 1);
1046 		do {
1047 			temp = upper;
1048 			if (upper < 0)
1049 				return upper;
1050 
1051 			lower = pdata->read(dev, reg);
1052 			if (lower < 0)
1053 				return lower;
1054 
1055 			upper = pdata->read(dev, reg + 1);
1056 		} while (temp != upper && --timeout);
1057 
1058 		if (timeout == 0)
1059 			return -EIO;
1060 
1061 		return (upper << 8) | lower;
1062 	}
1063 
1064 	return pdata->read(dev, reg);
1065 }
1066 
1067 static int bq27xxx_battery_platform_probe(struct platform_device *pdev)
1068 {
1069 	struct bq27xxx_device_info *di;
1070 	struct bq27xxx_platform_data *pdata = pdev->dev.platform_data;
1071 
1072 	if (!pdata) {
1073 		dev_err(&pdev->dev, "no platform_data supplied\n");
1074 		return -EINVAL;
1075 	}
1076 
1077 	if (!pdata->read) {
1078 		dev_err(&pdev->dev, "no hdq read callback supplied\n");
1079 		return -EINVAL;
1080 	}
1081 
1082 	if (!pdata->chip) {
1083 		dev_err(&pdev->dev, "no device supplied\n");
1084 		return -EINVAL;
1085 	}
1086 
1087 	di = devm_kzalloc(&pdev->dev, sizeof(*di), GFP_KERNEL);
1088 	if (!di)
1089 		return -ENOMEM;
1090 
1091 	platform_set_drvdata(pdev, di);
1092 
1093 	di->dev = &pdev->dev;
1094 	di->chip = pdata->chip;
1095 	di->name = pdata->name ?: dev_name(&pdev->dev);
1096 	di->bus.read = bq27xxx_battery_platform_read;
1097 
1098 	return bq27xxx_battery_setup(di);
1099 }
1100 
1101 static int bq27xxx_battery_platform_remove(struct platform_device *pdev)
1102 {
1103 	struct bq27xxx_device_info *di = platform_get_drvdata(pdev);
1104 
1105 	bq27xxx_battery_teardown(di);
1106 
1107 	return 0;
1108 }
1109 
1110 static const struct platform_device_id bq27xxx_battery_platform_id_table[] = {
1111 	{ "bq27000-battery", },
1112 	{ /* sentinel */ }
1113 };
1114 MODULE_DEVICE_TABLE(platform, bq27xxx_battery_platform_id_table);
1115 
1116 #ifdef CONFIG_OF
1117 static const struct of_device_id bq27xxx_battery_platform_of_match_table[] = {
1118 	{ .compatible = "ti,bq27000" },
1119 	{},
1120 };
1121 MODULE_DEVICE_TABLE(of, bq27xxx_battery_platform_of_match_table);
1122 #endif
1123 
1124 static struct platform_driver bq27xxx_battery_platform_driver = {
1125 	.probe	= bq27xxx_battery_platform_probe,
1126 	.remove = bq27xxx_battery_platform_remove,
1127 	.driver = {
1128 		.name = "bq27000-battery",
1129 		.of_match_table = of_match_ptr(bq27xxx_battery_platform_of_match_table),
1130 	},
1131 	.id_table = bq27xxx_battery_platform_id_table,
1132 };
1133 module_platform_driver(bq27xxx_battery_platform_driver);
1134 
1135 MODULE_ALIAS("platform:bq27000-battery");
1136 
1137 MODULE_AUTHOR("Rodolfo Giometti <giometti@linux.it>");
1138 MODULE_DESCRIPTION("BQ27xxx battery monitor driver");
1139 MODULE_LICENSE("GPL");
1140