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