1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3  * Gas Gauge driver for SBS Compliant Batteries
4  *
5  * Copyright (c) 2010, NVIDIA Corporation.
6  */
7 
8 #include <linux/bits.h>
9 #include <linux/delay.h>
10 #include <linux/err.h>
11 #include <linux/gpio/consumer.h>
12 #include <linux/i2c.h>
13 #include <linux/init.h>
14 #include <linux/interrupt.h>
15 #include <linux/kernel.h>
16 #include <linux/module.h>
17 #include <linux/property.h>
18 #include <linux/of_device.h>
19 #include <linux/power/sbs-battery.h>
20 #include <linux/power_supply.h>
21 #include <linux/slab.h>
22 #include <linux/stat.h>
23 
24 enum {
25 	REG_MANUFACTURER_DATA,
26 	REG_BATTERY_MODE,
27 	REG_TEMPERATURE,
28 	REG_VOLTAGE,
29 	REG_CURRENT_NOW,
30 	REG_CURRENT_AVG,
31 	REG_MAX_ERR,
32 	REG_CAPACITY,
33 	REG_TIME_TO_EMPTY,
34 	REG_TIME_TO_FULL,
35 	REG_STATUS,
36 	REG_CAPACITY_LEVEL,
37 	REG_CYCLE_COUNT,
38 	REG_SERIAL_NUMBER,
39 	REG_REMAINING_CAPACITY,
40 	REG_REMAINING_CAPACITY_CHARGE,
41 	REG_FULL_CHARGE_CAPACITY,
42 	REG_FULL_CHARGE_CAPACITY_CHARGE,
43 	REG_DESIGN_CAPACITY,
44 	REG_DESIGN_CAPACITY_CHARGE,
45 	REG_DESIGN_VOLTAGE_MIN,
46 	REG_DESIGN_VOLTAGE_MAX,
47 	REG_CHEMISTRY,
48 	REG_MANUFACTURER,
49 	REG_MODEL_NAME,
50 	REG_CHARGE_CURRENT,
51 	REG_CHARGE_VOLTAGE,
52 };
53 
54 #define REG_ADDR_SPEC_INFO		0x1A
55 #define SPEC_INFO_VERSION_MASK		GENMASK(7, 4)
56 #define SPEC_INFO_VERSION_SHIFT		4
57 
58 #define SBS_VERSION_1_0			1
59 #define SBS_VERSION_1_1			2
60 #define SBS_VERSION_1_1_WITH_PEC	3
61 
62 #define REG_ADDR_MANUFACTURE_DATE	0x1B
63 
64 /* Battery Mode defines */
65 #define BATTERY_MODE_OFFSET		0x03
66 #define BATTERY_MODE_CAPACITY_MASK	BIT(15)
67 enum sbs_capacity_mode {
68 	CAPACITY_MODE_AMPS = 0,
69 	CAPACITY_MODE_WATTS = BATTERY_MODE_CAPACITY_MASK
70 };
71 #define BATTERY_MODE_CHARGER_MASK	(1<<14)
72 
73 /* manufacturer access defines */
74 #define MANUFACTURER_ACCESS_STATUS	0x0006
75 #define MANUFACTURER_ACCESS_SLEEP	0x0011
76 
77 /* battery status value bits */
78 #define BATTERY_INITIALIZED		0x80
79 #define BATTERY_DISCHARGING		0x40
80 #define BATTERY_FULL_CHARGED		0x20
81 #define BATTERY_FULL_DISCHARGED		0x10
82 
83 /* min_value and max_value are only valid for numerical data */
84 #define SBS_DATA(_psp, _addr, _min_value, _max_value) { \
85 	.psp = _psp, \
86 	.addr = _addr, \
87 	.min_value = _min_value, \
88 	.max_value = _max_value, \
89 }
90 
91 static const struct chip_data {
92 	enum power_supply_property psp;
93 	u8 addr;
94 	int min_value;
95 	int max_value;
96 } sbs_data[] = {
97 	[REG_MANUFACTURER_DATA] =
98 		SBS_DATA(POWER_SUPPLY_PROP_PRESENT, 0x00, 0, 65535),
99 	[REG_BATTERY_MODE] =
100 		SBS_DATA(-1, 0x03, 0, 65535),
101 	[REG_TEMPERATURE] =
102 		SBS_DATA(POWER_SUPPLY_PROP_TEMP, 0x08, 0, 65535),
103 	[REG_VOLTAGE] =
104 		SBS_DATA(POWER_SUPPLY_PROP_VOLTAGE_NOW, 0x09, 0, 20000),
105 	[REG_CURRENT_NOW] =
106 		SBS_DATA(POWER_SUPPLY_PROP_CURRENT_NOW, 0x0A, -32768, 32767),
107 	[REG_CURRENT_AVG] =
108 		SBS_DATA(POWER_SUPPLY_PROP_CURRENT_AVG, 0x0B, -32768, 32767),
109 	[REG_MAX_ERR] =
110 		SBS_DATA(POWER_SUPPLY_PROP_CAPACITY_ERROR_MARGIN, 0x0c, 0, 100),
111 	[REG_CAPACITY] =
112 		SBS_DATA(POWER_SUPPLY_PROP_CAPACITY, 0x0D, 0, 100),
113 	[REG_REMAINING_CAPACITY] =
114 		SBS_DATA(POWER_SUPPLY_PROP_ENERGY_NOW, 0x0F, 0, 65535),
115 	[REG_REMAINING_CAPACITY_CHARGE] =
116 		SBS_DATA(POWER_SUPPLY_PROP_CHARGE_NOW, 0x0F, 0, 65535),
117 	[REG_FULL_CHARGE_CAPACITY] =
118 		SBS_DATA(POWER_SUPPLY_PROP_ENERGY_FULL, 0x10, 0, 65535),
119 	[REG_FULL_CHARGE_CAPACITY_CHARGE] =
120 		SBS_DATA(POWER_SUPPLY_PROP_CHARGE_FULL, 0x10, 0, 65535),
121 	[REG_TIME_TO_EMPTY] =
122 		SBS_DATA(POWER_SUPPLY_PROP_TIME_TO_EMPTY_AVG, 0x12, 0, 65535),
123 	[REG_TIME_TO_FULL] =
124 		SBS_DATA(POWER_SUPPLY_PROP_TIME_TO_FULL_AVG, 0x13, 0, 65535),
125 	[REG_CHARGE_CURRENT] =
126 		SBS_DATA(POWER_SUPPLY_PROP_CONSTANT_CHARGE_CURRENT_MAX, 0x14, 0, 65535),
127 	[REG_CHARGE_VOLTAGE] =
128 		SBS_DATA(POWER_SUPPLY_PROP_CONSTANT_CHARGE_VOLTAGE_MAX, 0x15, 0, 65535),
129 	[REG_STATUS] =
130 		SBS_DATA(POWER_SUPPLY_PROP_STATUS, 0x16, 0, 65535),
131 	[REG_CAPACITY_LEVEL] =
132 		SBS_DATA(POWER_SUPPLY_PROP_CAPACITY_LEVEL, 0x16, 0, 65535),
133 	[REG_CYCLE_COUNT] =
134 		SBS_DATA(POWER_SUPPLY_PROP_CYCLE_COUNT, 0x17, 0, 65535),
135 	[REG_DESIGN_CAPACITY] =
136 		SBS_DATA(POWER_SUPPLY_PROP_ENERGY_FULL_DESIGN, 0x18, 0, 65535),
137 	[REG_DESIGN_CAPACITY_CHARGE] =
138 		SBS_DATA(POWER_SUPPLY_PROP_CHARGE_FULL_DESIGN, 0x18, 0, 65535),
139 	[REG_DESIGN_VOLTAGE_MIN] =
140 		SBS_DATA(POWER_SUPPLY_PROP_VOLTAGE_MIN_DESIGN, 0x19, 0, 65535),
141 	[REG_DESIGN_VOLTAGE_MAX] =
142 		SBS_DATA(POWER_SUPPLY_PROP_VOLTAGE_MAX_DESIGN, 0x19, 0, 65535),
143 	[REG_SERIAL_NUMBER] =
144 		SBS_DATA(POWER_SUPPLY_PROP_SERIAL_NUMBER, 0x1C, 0, 65535),
145 	/* Properties of type `const char *' */
146 	[REG_MANUFACTURER] =
147 		SBS_DATA(POWER_SUPPLY_PROP_MANUFACTURER, 0x20, 0, 65535),
148 	[REG_MODEL_NAME] =
149 		SBS_DATA(POWER_SUPPLY_PROP_MODEL_NAME, 0x21, 0, 65535),
150 	[REG_CHEMISTRY] =
151 		SBS_DATA(POWER_SUPPLY_PROP_TECHNOLOGY, 0x22, 0, 65535)
152 };
153 
154 static const enum power_supply_property sbs_properties[] = {
155 	POWER_SUPPLY_PROP_STATUS,
156 	POWER_SUPPLY_PROP_CAPACITY_LEVEL,
157 	POWER_SUPPLY_PROP_HEALTH,
158 	POWER_SUPPLY_PROP_PRESENT,
159 	POWER_SUPPLY_PROP_TECHNOLOGY,
160 	POWER_SUPPLY_PROP_CYCLE_COUNT,
161 	POWER_SUPPLY_PROP_VOLTAGE_NOW,
162 	POWER_SUPPLY_PROP_CURRENT_NOW,
163 	POWER_SUPPLY_PROP_CURRENT_AVG,
164 	POWER_SUPPLY_PROP_CAPACITY,
165 	POWER_SUPPLY_PROP_CAPACITY_ERROR_MARGIN,
166 	POWER_SUPPLY_PROP_TEMP,
167 	POWER_SUPPLY_PROP_TIME_TO_EMPTY_AVG,
168 	POWER_SUPPLY_PROP_TIME_TO_FULL_AVG,
169 	POWER_SUPPLY_PROP_SERIAL_NUMBER,
170 	POWER_SUPPLY_PROP_VOLTAGE_MIN_DESIGN,
171 	POWER_SUPPLY_PROP_VOLTAGE_MAX_DESIGN,
172 	POWER_SUPPLY_PROP_ENERGY_NOW,
173 	POWER_SUPPLY_PROP_ENERGY_FULL,
174 	POWER_SUPPLY_PROP_ENERGY_FULL_DESIGN,
175 	POWER_SUPPLY_PROP_CHARGE_NOW,
176 	POWER_SUPPLY_PROP_CHARGE_FULL,
177 	POWER_SUPPLY_PROP_CHARGE_FULL_DESIGN,
178 	POWER_SUPPLY_PROP_CONSTANT_CHARGE_CURRENT_MAX,
179 	POWER_SUPPLY_PROP_CONSTANT_CHARGE_VOLTAGE_MAX,
180 	POWER_SUPPLY_PROP_MANUFACTURE_YEAR,
181 	POWER_SUPPLY_PROP_MANUFACTURE_MONTH,
182 	POWER_SUPPLY_PROP_MANUFACTURE_DAY,
183 	/* Properties of type `const char *' */
184 	POWER_SUPPLY_PROP_MANUFACTURER,
185 	POWER_SUPPLY_PROP_MODEL_NAME
186 };
187 
188 /* Supports special manufacturer commands from TI BQ20Z65 and BQ20Z75 IC. */
189 #define SBS_FLAGS_TI_BQ20ZX5		BIT(0)
190 
191 struct sbs_info {
192 	struct i2c_client		*client;
193 	struct power_supply		*power_supply;
194 	bool				is_present;
195 	struct gpio_desc		*gpio_detect;
196 	bool				charger_broadcasts;
197 	int				last_state;
198 	int				poll_time;
199 	u32				i2c_retry_count;
200 	u32				poll_retry_count;
201 	struct delayed_work		work;
202 	struct mutex			mode_lock;
203 	u32				flags;
204 };
205 
206 static char model_name[I2C_SMBUS_BLOCK_MAX + 1];
207 static char manufacturer[I2C_SMBUS_BLOCK_MAX + 1];
208 static char chemistry[I2C_SMBUS_BLOCK_MAX + 1];
209 static bool force_load;
210 
211 static int sbs_read_word_data(struct i2c_client *client, u8 address);
212 static int sbs_write_word_data(struct i2c_client *client, u8 address, u16 value);
213 
214 static void sbs_disable_charger_broadcasts(struct sbs_info *chip)
215 {
216 	int val = sbs_read_word_data(chip->client, BATTERY_MODE_OFFSET);
217 	if (val < 0)
218 		goto exit;
219 
220 	val |= BATTERY_MODE_CHARGER_MASK;
221 
222 	val = sbs_write_word_data(chip->client, BATTERY_MODE_OFFSET, val);
223 
224 exit:
225 	if (val < 0)
226 		dev_err(&chip->client->dev,
227 			"Failed to disable charger broadcasting: %d\n", val);
228 	else
229 		dev_dbg(&chip->client->dev, "%s\n", __func__);
230 }
231 
232 static int sbs_update_presence(struct sbs_info *chip, bool is_present)
233 {
234 	struct i2c_client *client = chip->client;
235 	int retries = chip->i2c_retry_count;
236 	s32 ret = 0;
237 	u8 version;
238 
239 	if (chip->is_present == is_present)
240 		return 0;
241 
242 	if (!is_present) {
243 		chip->is_present = false;
244 		/* Disable PEC when no device is present */
245 		client->flags &= ~I2C_CLIENT_PEC;
246 		return 0;
247 	}
248 
249 	/* Check if device supports packet error checking and use it */
250 	while (retries > 0) {
251 		ret = i2c_smbus_read_word_data(client, REG_ADDR_SPEC_INFO);
252 		if (ret >= 0)
253 			break;
254 
255 		/*
256 		 * Some batteries trigger the detection pin before the
257 		 * I2C bus is properly connected. This works around the
258 		 * issue.
259 		 */
260 		msleep(100);
261 
262 		retries--;
263 	}
264 
265 	if (ret < 0) {
266 		dev_dbg(&client->dev, "failed to read spec info: %d\n", ret);
267 
268 		/* fallback to old behaviour */
269 		client->flags &= ~I2C_CLIENT_PEC;
270 		chip->is_present = true;
271 
272 		return ret;
273 	}
274 
275 	version = (ret & SPEC_INFO_VERSION_MASK) >> SPEC_INFO_VERSION_SHIFT;
276 
277 	if (version == SBS_VERSION_1_1_WITH_PEC)
278 		client->flags |= I2C_CLIENT_PEC;
279 	else
280 		client->flags &= ~I2C_CLIENT_PEC;
281 
282 	if (of_device_is_compatible(client->dev.parent->of_node, "google,cros-ec-i2c-tunnel")
283 	    && client->flags & I2C_CLIENT_PEC) {
284 		dev_info(&client->dev, "Disabling PEC because of broken Cros-EC implementation\n");
285 		client->flags &= ~I2C_CLIENT_PEC;
286 	}
287 
288 	dev_dbg(&client->dev, "PEC: %s\n", (client->flags & I2C_CLIENT_PEC) ?
289 		"enabled" : "disabled");
290 
291 	if (!chip->is_present && is_present && !chip->charger_broadcasts)
292 		sbs_disable_charger_broadcasts(chip);
293 
294 	chip->is_present = true;
295 
296 	return 0;
297 }
298 
299 static int sbs_read_word_data(struct i2c_client *client, u8 address)
300 {
301 	struct sbs_info *chip = i2c_get_clientdata(client);
302 	int retries = chip->i2c_retry_count;
303 	s32 ret = 0;
304 
305 	while (retries > 0) {
306 		ret = i2c_smbus_read_word_data(client, address);
307 		if (ret >= 0)
308 			break;
309 		retries--;
310 	}
311 
312 	if (ret < 0) {
313 		dev_dbg(&client->dev,
314 			"%s: i2c read at address 0x%x failed\n",
315 			__func__, address);
316 		return ret;
317 	}
318 
319 	return ret;
320 }
321 
322 static int sbs_read_string_data_fallback(struct i2c_client *client, u8 address, char *values)
323 {
324 	struct sbs_info *chip = i2c_get_clientdata(client);
325 	s32 ret = 0, block_length = 0;
326 	int retries_length, retries_block;
327 	u8 block_buffer[I2C_SMBUS_BLOCK_MAX + 1];
328 
329 	retries_length = chip->i2c_retry_count;
330 	retries_block = chip->i2c_retry_count;
331 
332 	dev_warn_once(&client->dev, "I2C adapter does not support I2C_FUNC_SMBUS_READ_BLOCK_DATA.\n"
333 				    "Fallback method does not support PEC.\n");
334 
335 	/* Adapter needs to support these two functions */
336 	if (!i2c_check_functionality(client->adapter,
337 				     I2C_FUNC_SMBUS_BYTE_DATA |
338 				     I2C_FUNC_SMBUS_I2C_BLOCK)){
339 		return -ENODEV;
340 	}
341 
342 	/* Get the length of block data */
343 	while (retries_length > 0) {
344 		ret = i2c_smbus_read_byte_data(client, address);
345 		if (ret >= 0)
346 			break;
347 		retries_length--;
348 	}
349 
350 	if (ret < 0) {
351 		dev_dbg(&client->dev,
352 			"%s: i2c read at address 0x%x failed\n",
353 			__func__, address);
354 		return ret;
355 	}
356 
357 	/* block_length does not include NULL terminator */
358 	block_length = ret;
359 	if (block_length > I2C_SMBUS_BLOCK_MAX) {
360 		dev_err(&client->dev,
361 			"%s: Returned block_length is longer than 0x%x\n",
362 			__func__, I2C_SMBUS_BLOCK_MAX);
363 		return -EINVAL;
364 	}
365 
366 	/* Get the block data */
367 	while (retries_block > 0) {
368 		ret = i2c_smbus_read_i2c_block_data(
369 				client, address,
370 				block_length + 1, block_buffer);
371 		if (ret >= 0)
372 			break;
373 		retries_block--;
374 	}
375 
376 	if (ret < 0) {
377 		dev_dbg(&client->dev,
378 			"%s: i2c read at address 0x%x failed\n",
379 			__func__, address);
380 		return ret;
381 	}
382 
383 	/* block_buffer[0] == block_length */
384 	memcpy(values, block_buffer + 1, block_length);
385 	values[block_length] = '\0';
386 
387 	return ret;
388 }
389 
390 static int sbs_read_string_data(struct i2c_client *client, u8 address, char *values)
391 {
392 	struct sbs_info *chip = i2c_get_clientdata(client);
393 	int retries = chip->i2c_retry_count;
394 	int ret = 0;
395 
396 	if (!i2c_check_functionality(client->adapter, I2C_FUNC_SMBUS_READ_BLOCK_DATA)) {
397 		bool pec = client->flags & I2C_CLIENT_PEC;
398 		client->flags &= ~I2C_CLIENT_PEC;
399 		ret = sbs_read_string_data_fallback(client, address, values);
400 		if (pec)
401 			client->flags |= I2C_CLIENT_PEC;
402 		return ret;
403 	}
404 
405 	while (retries > 0) {
406 		ret = i2c_smbus_read_block_data(client, address, values);
407 		if (ret >= 0)
408 			break;
409 		retries--;
410 	}
411 
412 	if (ret < 0) {
413 		dev_dbg(&client->dev, "failed to read block 0x%x: %d\n", address, ret);
414 		return ret;
415 	}
416 
417 	/* add string termination */
418 	values[ret] = '\0';
419 	return ret;
420 }
421 
422 static int sbs_write_word_data(struct i2c_client *client, u8 address,
423 	u16 value)
424 {
425 	struct sbs_info *chip = i2c_get_clientdata(client);
426 	int retries = chip->i2c_retry_count;
427 	s32 ret = 0;
428 
429 	while (retries > 0) {
430 		ret = i2c_smbus_write_word_data(client, address, value);
431 		if (ret >= 0)
432 			break;
433 		retries--;
434 	}
435 
436 	if (ret < 0) {
437 		dev_dbg(&client->dev,
438 			"%s: i2c write to address 0x%x failed\n",
439 			__func__, address);
440 		return ret;
441 	}
442 
443 	return 0;
444 }
445 
446 static int sbs_status_correct(struct i2c_client *client, int *intval)
447 {
448 	int ret;
449 
450 	ret = sbs_read_word_data(client, sbs_data[REG_CURRENT_NOW].addr);
451 	if (ret < 0)
452 		return ret;
453 
454 	ret = (s16)ret;
455 
456 	/* Not drawing current -> not charging (i.e. idle) */
457 	if (*intval != POWER_SUPPLY_STATUS_FULL && ret == 0)
458 		*intval = POWER_SUPPLY_STATUS_NOT_CHARGING;
459 
460 	if (*intval == POWER_SUPPLY_STATUS_FULL) {
461 		/* Drawing or providing current when full */
462 		if (ret > 0)
463 			*intval = POWER_SUPPLY_STATUS_CHARGING;
464 		else if (ret < 0)
465 			*intval = POWER_SUPPLY_STATUS_DISCHARGING;
466 	}
467 
468 	return 0;
469 }
470 
471 static bool sbs_bat_needs_calibration(struct i2c_client *client)
472 {
473 	int ret;
474 
475 	ret = sbs_read_word_data(client, sbs_data[REG_BATTERY_MODE].addr);
476 	if (ret < 0)
477 		return false;
478 
479 	return !!(ret & BIT(7));
480 }
481 
482 static int sbs_get_ti_battery_presence_and_health(
483 	struct i2c_client *client, enum power_supply_property psp,
484 	union power_supply_propval *val)
485 {
486 	s32 ret;
487 
488 	/*
489 	 * Write to ManufacturerAccess with ManufacturerAccess command
490 	 * and then read the status.
491 	 */
492 	ret = sbs_write_word_data(client, sbs_data[REG_MANUFACTURER_DATA].addr,
493 				  MANUFACTURER_ACCESS_STATUS);
494 	if (ret < 0) {
495 		if (psp == POWER_SUPPLY_PROP_PRESENT)
496 			val->intval = 0; /* battery removed */
497 		return ret;
498 	}
499 
500 	ret = sbs_read_word_data(client, sbs_data[REG_MANUFACTURER_DATA].addr);
501 	if (ret < 0) {
502 		if (psp == POWER_SUPPLY_PROP_PRESENT)
503 			val->intval = 0; /* battery removed */
504 		return ret;
505 	}
506 
507 	if (ret < sbs_data[REG_MANUFACTURER_DATA].min_value ||
508 	    ret > sbs_data[REG_MANUFACTURER_DATA].max_value) {
509 		val->intval = 0;
510 		return 0;
511 	}
512 
513 	/* Mask the upper nibble of 2nd byte and
514 	 * lower byte of response then
515 	 * shift the result by 8 to get status*/
516 	ret &= 0x0F00;
517 	ret >>= 8;
518 	if (psp == POWER_SUPPLY_PROP_PRESENT) {
519 		if (ret == 0x0F)
520 			/* battery removed */
521 			val->intval = 0;
522 		else
523 			val->intval = 1;
524 	} else if (psp == POWER_SUPPLY_PROP_HEALTH) {
525 		if (ret == 0x09)
526 			val->intval = POWER_SUPPLY_HEALTH_UNSPEC_FAILURE;
527 		else if (ret == 0x0B)
528 			val->intval = POWER_SUPPLY_HEALTH_OVERHEAT;
529 		else if (ret == 0x0C)
530 			val->intval = POWER_SUPPLY_HEALTH_DEAD;
531 		else if (sbs_bat_needs_calibration(client))
532 			val->intval = POWER_SUPPLY_HEALTH_CALIBRATION_REQUIRED;
533 		else
534 			val->intval = POWER_SUPPLY_HEALTH_GOOD;
535 	}
536 
537 	return 0;
538 }
539 
540 static int sbs_get_battery_presence_and_health(
541 	struct i2c_client *client, enum power_supply_property psp,
542 	union power_supply_propval *val)
543 {
544 	struct sbs_info *chip = i2c_get_clientdata(client);
545 	int ret;
546 
547 	if (chip->flags & SBS_FLAGS_TI_BQ20ZX5)
548 		return sbs_get_ti_battery_presence_and_health(client, psp, val);
549 
550 	/* Dummy command; if it succeeds, battery is present. */
551 	ret = sbs_read_word_data(client, sbs_data[REG_STATUS].addr);
552 
553 	if (ret < 0) { /* battery not present*/
554 		if (psp == POWER_SUPPLY_PROP_PRESENT) {
555 			val->intval = 0;
556 			return 0;
557 		}
558 		return ret;
559 	}
560 
561 	if (psp == POWER_SUPPLY_PROP_PRESENT)
562 		val->intval = 1; /* battery present */
563 	else { /* POWER_SUPPLY_PROP_HEALTH */
564 		if (sbs_bat_needs_calibration(client)) {
565 			val->intval = POWER_SUPPLY_HEALTH_CALIBRATION_REQUIRED;
566 		} else {
567 			/* SBS spec doesn't have a general health command. */
568 			val->intval = POWER_SUPPLY_HEALTH_UNKNOWN;
569 		}
570 	}
571 
572 	return 0;
573 }
574 
575 static int sbs_get_battery_property(struct i2c_client *client,
576 	int reg_offset, enum power_supply_property psp,
577 	union power_supply_propval *val)
578 {
579 	struct sbs_info *chip = i2c_get_clientdata(client);
580 	s32 ret;
581 
582 	ret = sbs_read_word_data(client, sbs_data[reg_offset].addr);
583 	if (ret < 0)
584 		return ret;
585 
586 	/* returned values are 16 bit */
587 	if (sbs_data[reg_offset].min_value < 0)
588 		ret = (s16)ret;
589 
590 	if (ret >= sbs_data[reg_offset].min_value &&
591 	    ret <= sbs_data[reg_offset].max_value) {
592 		val->intval = ret;
593 		if (psp == POWER_SUPPLY_PROP_CAPACITY_LEVEL) {
594 			if (!(ret & BATTERY_INITIALIZED))
595 				val->intval =
596 					POWER_SUPPLY_CAPACITY_LEVEL_UNKNOWN;
597 			else if (ret & BATTERY_FULL_CHARGED)
598 				val->intval =
599 					POWER_SUPPLY_CAPACITY_LEVEL_FULL;
600 			else if (ret & BATTERY_FULL_DISCHARGED)
601 				val->intval =
602 					POWER_SUPPLY_CAPACITY_LEVEL_CRITICAL;
603 			else
604 				val->intval =
605 					POWER_SUPPLY_CAPACITY_LEVEL_NORMAL;
606 			return 0;
607 		} else if (psp != POWER_SUPPLY_PROP_STATUS) {
608 			return 0;
609 		}
610 
611 		if (ret & BATTERY_FULL_CHARGED)
612 			val->intval = POWER_SUPPLY_STATUS_FULL;
613 		else if (ret & BATTERY_DISCHARGING)
614 			val->intval = POWER_SUPPLY_STATUS_DISCHARGING;
615 		else
616 			val->intval = POWER_SUPPLY_STATUS_CHARGING;
617 
618 		sbs_status_correct(client, &val->intval);
619 
620 		if (chip->poll_time == 0)
621 			chip->last_state = val->intval;
622 		else if (chip->last_state != val->intval) {
623 			cancel_delayed_work_sync(&chip->work);
624 			power_supply_changed(chip->power_supply);
625 			chip->poll_time = 0;
626 		}
627 	} else {
628 		if (psp == POWER_SUPPLY_PROP_STATUS)
629 			val->intval = POWER_SUPPLY_STATUS_UNKNOWN;
630 		else if (psp == POWER_SUPPLY_PROP_CAPACITY)
631 			/* sbs spec says that this can be >100 %
632 			 * even if max value is 100 %
633 			 */
634 			val->intval = min(ret, 100);
635 		else
636 			val->intval = 0;
637 	}
638 
639 	return 0;
640 }
641 
642 static int sbs_get_battery_string_property(struct i2c_client *client,
643 	int reg_offset, enum power_supply_property psp, char *val)
644 {
645 	s32 ret;
646 
647 	ret = sbs_read_string_data(client, sbs_data[reg_offset].addr, val);
648 
649 	if (ret < 0)
650 		return ret;
651 
652 	return 0;
653 }
654 
655 static void  sbs_unit_adjustment(struct i2c_client *client,
656 	enum power_supply_property psp, union power_supply_propval *val)
657 {
658 #define BASE_UNIT_CONVERSION		1000
659 #define BATTERY_MODE_CAP_MULT_WATT	(10 * BASE_UNIT_CONVERSION)
660 #define TIME_UNIT_CONVERSION		60
661 #define TEMP_KELVIN_TO_CELSIUS		2731
662 	switch (psp) {
663 	case POWER_SUPPLY_PROP_ENERGY_NOW:
664 	case POWER_SUPPLY_PROP_ENERGY_FULL:
665 	case POWER_SUPPLY_PROP_ENERGY_FULL_DESIGN:
666 		/* sbs provides energy in units of 10mWh.
667 		 * Convert to µWh
668 		 */
669 		val->intval *= BATTERY_MODE_CAP_MULT_WATT;
670 		break;
671 
672 	case POWER_SUPPLY_PROP_VOLTAGE_NOW:
673 	case POWER_SUPPLY_PROP_VOLTAGE_MIN_DESIGN:
674 	case POWER_SUPPLY_PROP_VOLTAGE_MAX_DESIGN:
675 	case POWER_SUPPLY_PROP_CURRENT_NOW:
676 	case POWER_SUPPLY_PROP_CURRENT_AVG:
677 	case POWER_SUPPLY_PROP_CHARGE_NOW:
678 	case POWER_SUPPLY_PROP_CONSTANT_CHARGE_CURRENT_MAX:
679 	case POWER_SUPPLY_PROP_CONSTANT_CHARGE_VOLTAGE_MAX:
680 	case POWER_SUPPLY_PROP_CHARGE_FULL:
681 	case POWER_SUPPLY_PROP_CHARGE_FULL_DESIGN:
682 		val->intval *= BASE_UNIT_CONVERSION;
683 		break;
684 
685 	case POWER_SUPPLY_PROP_TEMP:
686 		/* sbs provides battery temperature in 0.1K
687 		 * so convert it to 0.1°C
688 		 */
689 		val->intval -= TEMP_KELVIN_TO_CELSIUS;
690 		break;
691 
692 	case POWER_SUPPLY_PROP_TIME_TO_EMPTY_AVG:
693 	case POWER_SUPPLY_PROP_TIME_TO_FULL_AVG:
694 		/* sbs provides time to empty and time to full in minutes.
695 		 * Convert to seconds
696 		 */
697 		val->intval *= TIME_UNIT_CONVERSION;
698 		break;
699 
700 	default:
701 		dev_dbg(&client->dev,
702 			"%s: no need for unit conversion %d\n", __func__, psp);
703 	}
704 }
705 
706 static enum sbs_capacity_mode sbs_set_capacity_mode(struct i2c_client *client,
707 	enum sbs_capacity_mode mode)
708 {
709 	int ret, original_val;
710 
711 	original_val = sbs_read_word_data(client, BATTERY_MODE_OFFSET);
712 	if (original_val < 0)
713 		return original_val;
714 
715 	if ((original_val & BATTERY_MODE_CAPACITY_MASK) == mode)
716 		return mode;
717 
718 	if (mode == CAPACITY_MODE_AMPS)
719 		ret = original_val & ~BATTERY_MODE_CAPACITY_MASK;
720 	else
721 		ret = original_val | BATTERY_MODE_CAPACITY_MASK;
722 
723 	ret = sbs_write_word_data(client, BATTERY_MODE_OFFSET, ret);
724 	if (ret < 0)
725 		return ret;
726 
727 	usleep_range(1000, 2000);
728 
729 	return original_val & BATTERY_MODE_CAPACITY_MASK;
730 }
731 
732 static int sbs_get_battery_capacity(struct i2c_client *client,
733 	int reg_offset, enum power_supply_property psp,
734 	union power_supply_propval *val)
735 {
736 	s32 ret;
737 	enum sbs_capacity_mode mode = CAPACITY_MODE_WATTS;
738 
739 	if (power_supply_is_amp_property(psp))
740 		mode = CAPACITY_MODE_AMPS;
741 
742 	mode = sbs_set_capacity_mode(client, mode);
743 	if ((int)mode < 0)
744 		return mode;
745 
746 	ret = sbs_read_word_data(client, sbs_data[reg_offset].addr);
747 	if (ret < 0)
748 		return ret;
749 
750 	val->intval = ret;
751 
752 	ret = sbs_set_capacity_mode(client, mode);
753 	if (ret < 0)
754 		return ret;
755 
756 	return 0;
757 }
758 
759 static char sbs_serial[5];
760 static int sbs_get_battery_serial_number(struct i2c_client *client,
761 	union power_supply_propval *val)
762 {
763 	int ret;
764 
765 	ret = sbs_read_word_data(client, sbs_data[REG_SERIAL_NUMBER].addr);
766 	if (ret < 0)
767 		return ret;
768 
769 	sprintf(sbs_serial, "%04x", ret);
770 	val->strval = sbs_serial;
771 
772 	return 0;
773 }
774 
775 static int sbs_get_property_index(struct i2c_client *client,
776 	enum power_supply_property psp)
777 {
778 	int count;
779 	for (count = 0; count < ARRAY_SIZE(sbs_data); count++)
780 		if (psp == sbs_data[count].psp)
781 			return count;
782 
783 	dev_warn(&client->dev,
784 		"%s: Invalid Property - %d\n", __func__, psp);
785 
786 	return -EINVAL;
787 }
788 
789 static int sbs_get_chemistry(struct i2c_client *client,
790 		union power_supply_propval *val)
791 {
792 	enum power_supply_property psp = POWER_SUPPLY_PROP_TECHNOLOGY;
793 	int ret;
794 
795 	ret = sbs_get_property_index(client, psp);
796 	if (ret < 0)
797 		return ret;
798 
799 	ret = sbs_get_battery_string_property(client, ret, psp,
800 					      chemistry);
801 	if (ret < 0)
802 		return ret;
803 
804 	if (!strncasecmp(chemistry, "LION", 4))
805 		val->intval = POWER_SUPPLY_TECHNOLOGY_LION;
806 	else if (!strncasecmp(chemistry, "LiP", 3))
807 		val->intval = POWER_SUPPLY_TECHNOLOGY_LIPO;
808 	else if (!strncasecmp(chemistry, "NiCd", 4))
809 		val->intval = POWER_SUPPLY_TECHNOLOGY_NiCd;
810 	else if (!strncasecmp(chemistry, "NiMH", 4))
811 		val->intval = POWER_SUPPLY_TECHNOLOGY_NiMH;
812 	else
813 		val->intval = POWER_SUPPLY_TECHNOLOGY_UNKNOWN;
814 
815 	if (val->intval == POWER_SUPPLY_TECHNOLOGY_UNKNOWN)
816 		dev_warn(&client->dev, "Unknown chemistry: %s\n", chemistry);
817 
818 	return 0;
819 }
820 
821 static int sbs_get_battery_manufacture_date(struct i2c_client *client,
822 	enum power_supply_property psp,
823 	union power_supply_propval *val)
824 {
825 	int ret;
826 	u16 day, month, year;
827 
828 	ret = sbs_read_word_data(client, REG_ADDR_MANUFACTURE_DATE);
829 	if (ret < 0)
830 		return ret;
831 
832 	day   = ret   & GENMASK(4,  0);
833 	month = (ret  & GENMASK(8,  5)) >> 5;
834 	year  = ((ret & GENMASK(15, 9)) >> 9) + 1980;
835 
836 	switch (psp) {
837 	case POWER_SUPPLY_PROP_MANUFACTURE_YEAR:
838 		val->intval = year;
839 		break;
840 	case POWER_SUPPLY_PROP_MANUFACTURE_MONTH:
841 		val->intval = month;
842 		break;
843 	case POWER_SUPPLY_PROP_MANUFACTURE_DAY:
844 		val->intval = day;
845 		break;
846 	default:
847 		return -EINVAL;
848 	}
849 
850 	return 0;
851 }
852 
853 static int sbs_get_property(struct power_supply *psy,
854 	enum power_supply_property psp,
855 	union power_supply_propval *val)
856 {
857 	int ret = 0;
858 	struct sbs_info *chip = power_supply_get_drvdata(psy);
859 	struct i2c_client *client = chip->client;
860 
861 	if (chip->gpio_detect) {
862 		ret = gpiod_get_value_cansleep(chip->gpio_detect);
863 		if (ret < 0)
864 			return ret;
865 		if (psp == POWER_SUPPLY_PROP_PRESENT) {
866 			val->intval = ret;
867 			sbs_update_presence(chip, ret);
868 			return 0;
869 		}
870 		if (ret == 0)
871 			return -ENODATA;
872 	}
873 
874 	switch (psp) {
875 	case POWER_SUPPLY_PROP_PRESENT:
876 	case POWER_SUPPLY_PROP_HEALTH:
877 		ret = sbs_get_battery_presence_and_health(client, psp, val);
878 
879 		/* this can only be true if no gpio is used */
880 		if (psp == POWER_SUPPLY_PROP_PRESENT)
881 			return 0;
882 		break;
883 
884 	case POWER_SUPPLY_PROP_TECHNOLOGY:
885 		ret = sbs_get_chemistry(client, val);
886 		if (ret < 0)
887 			break;
888 
889 		goto done; /* don't trigger power_supply_changed()! */
890 
891 	case POWER_SUPPLY_PROP_ENERGY_NOW:
892 	case POWER_SUPPLY_PROP_ENERGY_FULL:
893 	case POWER_SUPPLY_PROP_ENERGY_FULL_DESIGN:
894 	case POWER_SUPPLY_PROP_CHARGE_NOW:
895 	case POWER_SUPPLY_PROP_CHARGE_FULL:
896 	case POWER_SUPPLY_PROP_CHARGE_FULL_DESIGN:
897 		ret = sbs_get_property_index(client, psp);
898 		if (ret < 0)
899 			break;
900 
901 		/* sbs_get_battery_capacity() will change the battery mode
902 		 * temporarily to read the requested attribute. Ensure we stay
903 		 * in the desired mode for the duration of the attribute read.
904 		 */
905 		mutex_lock(&chip->mode_lock);
906 		ret = sbs_get_battery_capacity(client, ret, psp, val);
907 		mutex_unlock(&chip->mode_lock);
908 		break;
909 
910 	case POWER_SUPPLY_PROP_SERIAL_NUMBER:
911 		ret = sbs_get_battery_serial_number(client, val);
912 		break;
913 
914 	case POWER_SUPPLY_PROP_STATUS:
915 	case POWER_SUPPLY_PROP_CAPACITY_LEVEL:
916 	case POWER_SUPPLY_PROP_CYCLE_COUNT:
917 	case POWER_SUPPLY_PROP_VOLTAGE_NOW:
918 	case POWER_SUPPLY_PROP_CURRENT_NOW:
919 	case POWER_SUPPLY_PROP_CURRENT_AVG:
920 	case POWER_SUPPLY_PROP_TEMP:
921 	case POWER_SUPPLY_PROP_TIME_TO_EMPTY_AVG:
922 	case POWER_SUPPLY_PROP_TIME_TO_FULL_AVG:
923 	case POWER_SUPPLY_PROP_VOLTAGE_MIN_DESIGN:
924 	case POWER_SUPPLY_PROP_VOLTAGE_MAX_DESIGN:
925 	case POWER_SUPPLY_PROP_CONSTANT_CHARGE_CURRENT_MAX:
926 	case POWER_SUPPLY_PROP_CONSTANT_CHARGE_VOLTAGE_MAX:
927 	case POWER_SUPPLY_PROP_CAPACITY:
928 	case POWER_SUPPLY_PROP_CAPACITY_ERROR_MARGIN:
929 		ret = sbs_get_property_index(client, psp);
930 		if (ret < 0)
931 			break;
932 
933 		ret = sbs_get_battery_property(client, ret, psp, val);
934 		break;
935 
936 	case POWER_SUPPLY_PROP_MODEL_NAME:
937 		ret = sbs_get_property_index(client, psp);
938 		if (ret < 0)
939 			break;
940 
941 		ret = sbs_get_battery_string_property(client, ret, psp,
942 						      model_name);
943 		val->strval = model_name;
944 		break;
945 
946 	case POWER_SUPPLY_PROP_MANUFACTURER:
947 		ret = sbs_get_property_index(client, psp);
948 		if (ret < 0)
949 			break;
950 
951 		ret = sbs_get_battery_string_property(client, ret, psp,
952 						      manufacturer);
953 		val->strval = manufacturer;
954 		break;
955 
956 	case POWER_SUPPLY_PROP_MANUFACTURE_YEAR:
957 	case POWER_SUPPLY_PROP_MANUFACTURE_MONTH:
958 	case POWER_SUPPLY_PROP_MANUFACTURE_DAY:
959 		ret = sbs_get_battery_manufacture_date(client, psp, val);
960 		break;
961 
962 	default:
963 		dev_err(&client->dev,
964 			"%s: INVALID property\n", __func__);
965 		return -EINVAL;
966 	}
967 
968 	if (!chip->gpio_detect && chip->is_present != (ret >= 0)) {
969 		bool old_present = chip->is_present;
970 		union power_supply_propval val;
971 		int err = sbs_get_battery_presence_and_health(
972 				client, POWER_SUPPLY_PROP_PRESENT, &val);
973 
974 		sbs_update_presence(chip, !err && val.intval);
975 
976 		if (old_present != chip->is_present)
977 			power_supply_changed(chip->power_supply);
978 	}
979 
980 done:
981 	if (!ret) {
982 		/* Convert units to match requirements for power supply class */
983 		sbs_unit_adjustment(client, psp, val);
984 		dev_dbg(&client->dev,
985 			"%s: property = %d, value = %x\n", __func__,
986 			psp, val->intval);
987 	} else if (!chip->is_present)  {
988 		/* battery not present, so return NODATA for properties */
989 		ret = -ENODATA;
990 	}
991 	return ret;
992 }
993 
994 static void sbs_supply_changed(struct sbs_info *chip)
995 {
996 	struct power_supply *battery = chip->power_supply;
997 	int ret;
998 
999 	ret = gpiod_get_value_cansleep(chip->gpio_detect);
1000 	if (ret < 0)
1001 		return;
1002 	sbs_update_presence(chip, ret);
1003 	power_supply_changed(battery);
1004 }
1005 
1006 static irqreturn_t sbs_irq(int irq, void *devid)
1007 {
1008 	sbs_supply_changed(devid);
1009 	return IRQ_HANDLED;
1010 }
1011 
1012 static void sbs_alert(struct i2c_client *client, enum i2c_alert_protocol prot,
1013 	unsigned int data)
1014 {
1015 	sbs_supply_changed(i2c_get_clientdata(client));
1016 }
1017 
1018 static void sbs_external_power_changed(struct power_supply *psy)
1019 {
1020 	struct sbs_info *chip = power_supply_get_drvdata(psy);
1021 
1022 	/* cancel outstanding work */
1023 	cancel_delayed_work_sync(&chip->work);
1024 
1025 	schedule_delayed_work(&chip->work, HZ);
1026 	chip->poll_time = chip->poll_retry_count;
1027 }
1028 
1029 static void sbs_delayed_work(struct work_struct *work)
1030 {
1031 	struct sbs_info *chip;
1032 	s32 ret;
1033 
1034 	chip = container_of(work, struct sbs_info, work.work);
1035 
1036 	ret = sbs_read_word_data(chip->client, sbs_data[REG_STATUS].addr);
1037 	/* if the read failed, give up on this work */
1038 	if (ret < 0) {
1039 		chip->poll_time = 0;
1040 		return;
1041 	}
1042 
1043 	if (ret & BATTERY_FULL_CHARGED)
1044 		ret = POWER_SUPPLY_STATUS_FULL;
1045 	else if (ret & BATTERY_DISCHARGING)
1046 		ret = POWER_SUPPLY_STATUS_DISCHARGING;
1047 	else
1048 		ret = POWER_SUPPLY_STATUS_CHARGING;
1049 
1050 	sbs_status_correct(chip->client, &ret);
1051 
1052 	if (chip->last_state != ret) {
1053 		chip->poll_time = 0;
1054 		power_supply_changed(chip->power_supply);
1055 		return;
1056 	}
1057 	if (chip->poll_time > 0) {
1058 		schedule_delayed_work(&chip->work, HZ);
1059 		chip->poll_time--;
1060 		return;
1061 	}
1062 }
1063 
1064 static const struct power_supply_desc sbs_default_desc = {
1065 	.type = POWER_SUPPLY_TYPE_BATTERY,
1066 	.properties = sbs_properties,
1067 	.num_properties = ARRAY_SIZE(sbs_properties),
1068 	.get_property = sbs_get_property,
1069 	.external_power_changed = sbs_external_power_changed,
1070 };
1071 
1072 static int sbs_probe(struct i2c_client *client)
1073 {
1074 	struct sbs_info *chip;
1075 	struct power_supply_desc *sbs_desc;
1076 	struct sbs_platform_data *pdata = client->dev.platform_data;
1077 	struct power_supply_config psy_cfg = {};
1078 	int rc;
1079 	int irq;
1080 
1081 	sbs_desc = devm_kmemdup(&client->dev, &sbs_default_desc,
1082 			sizeof(*sbs_desc), GFP_KERNEL);
1083 	if (!sbs_desc)
1084 		return -ENOMEM;
1085 
1086 	sbs_desc->name = devm_kasprintf(&client->dev, GFP_KERNEL, "sbs-%s",
1087 			dev_name(&client->dev));
1088 	if (!sbs_desc->name)
1089 		return -ENOMEM;
1090 
1091 	chip = devm_kzalloc(&client->dev, sizeof(struct sbs_info), GFP_KERNEL);
1092 	if (!chip)
1093 		return -ENOMEM;
1094 
1095 	chip->flags = (u32)(uintptr_t)device_get_match_data(&client->dev);
1096 	chip->client = client;
1097 	psy_cfg.of_node = client->dev.of_node;
1098 	psy_cfg.drv_data = chip;
1099 	chip->last_state = POWER_SUPPLY_STATUS_UNKNOWN;
1100 	mutex_init(&chip->mode_lock);
1101 
1102 	/* use pdata if available, fall back to DT properties,
1103 	 * or hardcoded defaults if not
1104 	 */
1105 	rc = device_property_read_u32(&client->dev, "sbs,i2c-retry-count",
1106 				      &chip->i2c_retry_count);
1107 	if (rc)
1108 		chip->i2c_retry_count = 0;
1109 
1110 	rc = device_property_read_u32(&client->dev, "sbs,poll-retry-count",
1111 				      &chip->poll_retry_count);
1112 	if (rc)
1113 		chip->poll_retry_count = 0;
1114 
1115 	if (pdata) {
1116 		chip->poll_retry_count = pdata->poll_retry_count;
1117 		chip->i2c_retry_count  = pdata->i2c_retry_count;
1118 	}
1119 	chip->i2c_retry_count = chip->i2c_retry_count + 1;
1120 
1121 	chip->charger_broadcasts = !device_property_read_bool(&client->dev,
1122 					"sbs,disable-charger-broadcasts");
1123 
1124 	chip->gpio_detect = devm_gpiod_get_optional(&client->dev,
1125 			"sbs,battery-detect", GPIOD_IN);
1126 	if (IS_ERR(chip->gpio_detect)) {
1127 		dev_err(&client->dev, "Failed to get gpio: %ld\n",
1128 			PTR_ERR(chip->gpio_detect));
1129 		return PTR_ERR(chip->gpio_detect);
1130 	}
1131 
1132 	i2c_set_clientdata(client, chip);
1133 
1134 	if (!chip->gpio_detect)
1135 		goto skip_gpio;
1136 
1137 	irq = gpiod_to_irq(chip->gpio_detect);
1138 	if (irq <= 0) {
1139 		dev_warn(&client->dev, "Failed to get gpio as irq: %d\n", irq);
1140 		goto skip_gpio;
1141 	}
1142 
1143 	rc = devm_request_threaded_irq(&client->dev, irq, NULL, sbs_irq,
1144 		IRQF_TRIGGER_RISING | IRQF_TRIGGER_FALLING | IRQF_ONESHOT,
1145 		dev_name(&client->dev), chip);
1146 	if (rc) {
1147 		dev_warn(&client->dev, "Failed to request irq: %d\n", rc);
1148 		goto skip_gpio;
1149 	}
1150 
1151 skip_gpio:
1152 	/*
1153 	 * Before we register, we might need to make sure we can actually talk
1154 	 * to the battery.
1155 	 */
1156 	if (!(force_load || chip->gpio_detect)) {
1157 		union power_supply_propval val;
1158 
1159 		rc = sbs_get_battery_presence_and_health(
1160 				client, POWER_SUPPLY_PROP_PRESENT, &val);
1161 		if (rc < 0 || !val.intval) {
1162 			dev_err(&client->dev, "Failed to get present status\n");
1163 			rc = -ENODEV;
1164 			goto exit_psupply;
1165 		}
1166 	}
1167 
1168 	INIT_DELAYED_WORK(&chip->work, sbs_delayed_work);
1169 
1170 	chip->power_supply = devm_power_supply_register(&client->dev, sbs_desc,
1171 						   &psy_cfg);
1172 	if (IS_ERR(chip->power_supply)) {
1173 		dev_err(&client->dev,
1174 			"%s: Failed to register power supply\n", __func__);
1175 		rc = PTR_ERR(chip->power_supply);
1176 		goto exit_psupply;
1177 	}
1178 
1179 	dev_info(&client->dev,
1180 		"%s: battery gas gauge device registered\n", client->name);
1181 
1182 	return 0;
1183 
1184 exit_psupply:
1185 	return rc;
1186 }
1187 
1188 static int sbs_remove(struct i2c_client *client)
1189 {
1190 	struct sbs_info *chip = i2c_get_clientdata(client);
1191 
1192 	cancel_delayed_work_sync(&chip->work);
1193 
1194 	return 0;
1195 }
1196 
1197 #if defined CONFIG_PM_SLEEP
1198 
1199 static int sbs_suspend(struct device *dev)
1200 {
1201 	struct i2c_client *client = to_i2c_client(dev);
1202 	struct sbs_info *chip = i2c_get_clientdata(client);
1203 	int ret;
1204 
1205 	if (chip->poll_time > 0)
1206 		cancel_delayed_work_sync(&chip->work);
1207 
1208 	if (chip->flags & SBS_FLAGS_TI_BQ20ZX5) {
1209 		/* Write to manufacturer access with sleep command. */
1210 		ret = sbs_write_word_data(client,
1211 					  sbs_data[REG_MANUFACTURER_DATA].addr,
1212 					  MANUFACTURER_ACCESS_SLEEP);
1213 		if (chip->is_present && ret < 0)
1214 			return ret;
1215 	}
1216 
1217 	return 0;
1218 }
1219 
1220 static SIMPLE_DEV_PM_OPS(sbs_pm_ops, sbs_suspend, NULL);
1221 #define SBS_PM_OPS (&sbs_pm_ops)
1222 
1223 #else
1224 #define SBS_PM_OPS NULL
1225 #endif
1226 
1227 static const struct i2c_device_id sbs_id[] = {
1228 	{ "bq20z65", 0 },
1229 	{ "bq20z75", 0 },
1230 	{ "sbs-battery", 1 },
1231 	{}
1232 };
1233 MODULE_DEVICE_TABLE(i2c, sbs_id);
1234 
1235 static const struct of_device_id sbs_dt_ids[] = {
1236 	{ .compatible = "sbs,sbs-battery" },
1237 	{
1238 		.compatible = "ti,bq20z65",
1239 		.data = (void *)SBS_FLAGS_TI_BQ20ZX5,
1240 	},
1241 	{
1242 		.compatible = "ti,bq20z75",
1243 		.data = (void *)SBS_FLAGS_TI_BQ20ZX5,
1244 	},
1245 	{ }
1246 };
1247 MODULE_DEVICE_TABLE(of, sbs_dt_ids);
1248 
1249 static struct i2c_driver sbs_battery_driver = {
1250 	.probe_new	= sbs_probe,
1251 	.remove		= sbs_remove,
1252 	.alert		= sbs_alert,
1253 	.id_table	= sbs_id,
1254 	.driver = {
1255 		.name	= "sbs-battery",
1256 		.of_match_table = sbs_dt_ids,
1257 		.pm	= SBS_PM_OPS,
1258 	},
1259 };
1260 module_i2c_driver(sbs_battery_driver);
1261 
1262 MODULE_DESCRIPTION("SBS battery monitor driver");
1263 MODULE_LICENSE("GPL");
1264 
1265 module_param(force_load, bool, 0444);
1266 MODULE_PARM_DESC(force_load,
1267 		 "Attempt to load the driver even if no battery is connected");
1268