• Home
  • Line#
  • Scopes#
  • Navigate#
  • Raw
  • Download
1 /*
2  * Gas Gauge driver for SBS Compliant Batteries
3  *
4  * Copyright (c) 2010, NVIDIA Corporation.
5  *
6  * This program is free software; you can redistribute it and/or modify
7  * it under the terms of the GNU General Public License as published by
8  * the Free Software Foundation; either version 2 of the License, or
9  * (at your option) any later version.
10  *
11  * This program is distributed in the hope that it will be useful, but WITHOUT
12  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
13  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
14  * more details.
15  */
16 
17 #include <linux/delay.h>
18 #include <linux/err.h>
19 #include <linux/gpio/consumer.h>
20 #include <linux/i2c.h>
21 #include <linux/init.h>
22 #include <linux/interrupt.h>
23 #include <linux/kernel.h>
24 #include <linux/module.h>
25 #include <linux/of.h>
26 #include <linux/of_device.h>
27 #include <linux/power/sbs-battery.h>
28 #include <linux/power_supply.h>
29 #include <linux/slab.h>
30 #include <linux/stat.h>
31 
32 enum {
33 	REG_MANUFACTURER_DATA,
34 	REG_TEMPERATURE,
35 	REG_VOLTAGE,
36 	REG_CURRENT,
37 	REG_CAPACITY,
38 	REG_TIME_TO_EMPTY,
39 	REG_TIME_TO_FULL,
40 	REG_STATUS,
41 	REG_CAPACITY_LEVEL,
42 	REG_CYCLE_COUNT,
43 	REG_SERIAL_NUMBER,
44 	REG_REMAINING_CAPACITY,
45 	REG_REMAINING_CAPACITY_CHARGE,
46 	REG_FULL_CHARGE_CAPACITY,
47 	REG_FULL_CHARGE_CAPACITY_CHARGE,
48 	REG_DESIGN_CAPACITY,
49 	REG_DESIGN_CAPACITY_CHARGE,
50 	REG_DESIGN_VOLTAGE_MIN,
51 	REG_DESIGN_VOLTAGE_MAX,
52 	REG_MANUFACTURER,
53 	REG_MODEL_NAME,
54 };
55 
56 /* Battery Mode defines */
57 #define BATTERY_MODE_OFFSET		0x03
58 #define BATTERY_MODE_MASK		0x8000
59 enum sbs_battery_mode {
60 	BATTERY_MODE_AMPS = 0,
61 	BATTERY_MODE_WATTS = 0x8000
62 };
63 
64 /* manufacturer access defines */
65 #define MANUFACTURER_ACCESS_STATUS	0x0006
66 #define MANUFACTURER_ACCESS_SLEEP	0x0011
67 
68 /* battery status value bits */
69 #define BATTERY_INITIALIZED		0x80
70 #define BATTERY_DISCHARGING		0x40
71 #define BATTERY_FULL_CHARGED		0x20
72 #define BATTERY_FULL_DISCHARGED		0x10
73 
74 /* min_value and max_value are only valid for numerical data */
75 #define SBS_DATA(_psp, _addr, _min_value, _max_value) { \
76 	.psp = _psp, \
77 	.addr = _addr, \
78 	.min_value = _min_value, \
79 	.max_value = _max_value, \
80 }
81 
82 static const struct chip_data {
83 	enum power_supply_property psp;
84 	u8 addr;
85 	int min_value;
86 	int max_value;
87 } sbs_data[] = {
88 	[REG_MANUFACTURER_DATA] =
89 		SBS_DATA(POWER_SUPPLY_PROP_PRESENT, 0x00, 0, 65535),
90 	[REG_TEMPERATURE] =
91 		SBS_DATA(POWER_SUPPLY_PROP_TEMP, 0x08, 0, 65535),
92 	[REG_VOLTAGE] =
93 		SBS_DATA(POWER_SUPPLY_PROP_VOLTAGE_NOW, 0x09, 0, 20000),
94 	[REG_CURRENT] =
95 		SBS_DATA(POWER_SUPPLY_PROP_CURRENT_NOW, 0x0A, -32768, 32767),
96 	[REG_CAPACITY] =
97 		SBS_DATA(POWER_SUPPLY_PROP_CAPACITY, 0x0D, 0, 100),
98 	[REG_REMAINING_CAPACITY] =
99 		SBS_DATA(POWER_SUPPLY_PROP_ENERGY_NOW, 0x0F, 0, 65535),
100 	[REG_REMAINING_CAPACITY_CHARGE] =
101 		SBS_DATA(POWER_SUPPLY_PROP_CHARGE_NOW, 0x0F, 0, 65535),
102 	[REG_FULL_CHARGE_CAPACITY] =
103 		SBS_DATA(POWER_SUPPLY_PROP_ENERGY_FULL, 0x10, 0, 65535),
104 	[REG_FULL_CHARGE_CAPACITY_CHARGE] =
105 		SBS_DATA(POWER_SUPPLY_PROP_CHARGE_FULL, 0x10, 0, 65535),
106 	[REG_TIME_TO_EMPTY] =
107 		SBS_DATA(POWER_SUPPLY_PROP_TIME_TO_EMPTY_AVG, 0x12, 0, 65535),
108 	[REG_TIME_TO_FULL] =
109 		SBS_DATA(POWER_SUPPLY_PROP_TIME_TO_FULL_AVG, 0x13, 0, 65535),
110 	[REG_STATUS] =
111 		SBS_DATA(POWER_SUPPLY_PROP_STATUS, 0x16, 0, 65535),
112 	[REG_CAPACITY_LEVEL] =
113 		SBS_DATA(POWER_SUPPLY_PROP_CAPACITY_LEVEL, 0x16, 0, 65535),
114 	[REG_CYCLE_COUNT] =
115 		SBS_DATA(POWER_SUPPLY_PROP_CYCLE_COUNT, 0x17, 0, 65535),
116 	[REG_DESIGN_CAPACITY] =
117 		SBS_DATA(POWER_SUPPLY_PROP_ENERGY_FULL_DESIGN, 0x18, 0, 65535),
118 	[REG_DESIGN_CAPACITY_CHARGE] =
119 		SBS_DATA(POWER_SUPPLY_PROP_CHARGE_FULL_DESIGN, 0x18, 0, 65535),
120 	[REG_DESIGN_VOLTAGE_MIN] =
121 		SBS_DATA(POWER_SUPPLY_PROP_VOLTAGE_MIN_DESIGN, 0x19, 0, 65535),
122 	[REG_DESIGN_VOLTAGE_MAX] =
123 		SBS_DATA(POWER_SUPPLY_PROP_VOLTAGE_MAX_DESIGN, 0x19, 0, 65535),
124 	[REG_SERIAL_NUMBER] =
125 		SBS_DATA(POWER_SUPPLY_PROP_SERIAL_NUMBER, 0x1C, 0, 65535),
126 	/* Properties of type `const char *' */
127 	[REG_MANUFACTURER] =
128 		SBS_DATA(POWER_SUPPLY_PROP_MANUFACTURER, 0x20, 0, 65535),
129 	[REG_MODEL_NAME] =
130 		SBS_DATA(POWER_SUPPLY_PROP_MODEL_NAME, 0x21, 0, 65535)
131 };
132 
133 static enum power_supply_property sbs_properties[] = {
134 	POWER_SUPPLY_PROP_STATUS,
135 	POWER_SUPPLY_PROP_CAPACITY_LEVEL,
136 	POWER_SUPPLY_PROP_HEALTH,
137 	POWER_SUPPLY_PROP_PRESENT,
138 	POWER_SUPPLY_PROP_TECHNOLOGY,
139 	POWER_SUPPLY_PROP_CYCLE_COUNT,
140 	POWER_SUPPLY_PROP_VOLTAGE_NOW,
141 	POWER_SUPPLY_PROP_CURRENT_NOW,
142 	POWER_SUPPLY_PROP_CAPACITY,
143 	POWER_SUPPLY_PROP_TEMP,
144 	POWER_SUPPLY_PROP_TIME_TO_EMPTY_AVG,
145 	POWER_SUPPLY_PROP_TIME_TO_FULL_AVG,
146 	POWER_SUPPLY_PROP_SERIAL_NUMBER,
147 	POWER_SUPPLY_PROP_VOLTAGE_MIN_DESIGN,
148 	POWER_SUPPLY_PROP_VOLTAGE_MAX_DESIGN,
149 	POWER_SUPPLY_PROP_ENERGY_NOW,
150 	POWER_SUPPLY_PROP_ENERGY_FULL,
151 	POWER_SUPPLY_PROP_ENERGY_FULL_DESIGN,
152 	POWER_SUPPLY_PROP_CHARGE_NOW,
153 	POWER_SUPPLY_PROP_CHARGE_FULL,
154 	POWER_SUPPLY_PROP_CHARGE_FULL_DESIGN,
155 	/* Properties of type `const char *' */
156 	POWER_SUPPLY_PROP_MANUFACTURER,
157 	POWER_SUPPLY_PROP_MODEL_NAME
158 };
159 
160 /* Supports special manufacturer commands from TI BQ20Z75 IC. */
161 #define SBS_FLAGS_TI_BQ20Z75		BIT(0)
162 
163 struct sbs_info {
164 	struct i2c_client		*client;
165 	struct power_supply		*power_supply;
166 	bool				is_present;
167 	struct gpio_desc		*gpio_detect;
168 	bool				enable_detection;
169 	int				last_state;
170 	int				poll_time;
171 	u32				i2c_retry_count;
172 	u32				poll_retry_count;
173 	struct delayed_work		work;
174 	struct mutex			mode_lock;
175 	u32				flags;
176 };
177 
178 static char model_name[I2C_SMBUS_BLOCK_MAX + 1];
179 static char manufacturer[I2C_SMBUS_BLOCK_MAX + 1];
180 static bool force_load;
181 
sbs_read_word_data(struct i2c_client * client,u8 address)182 static int sbs_read_word_data(struct i2c_client *client, u8 address)
183 {
184 	struct sbs_info *chip = i2c_get_clientdata(client);
185 	int retries = chip->i2c_retry_count;
186 	s32 ret = 0;
187 
188 	while (retries > 0) {
189 		ret = i2c_smbus_read_word_data(client, address);
190 		if (ret >= 0)
191 			break;
192 		retries--;
193 	}
194 
195 	if (ret < 0) {
196 		dev_dbg(&client->dev,
197 			"%s: i2c read at address 0x%x failed\n",
198 			__func__, address);
199 		return ret;
200 	}
201 
202 	return ret;
203 }
204 
sbs_read_string_data(struct i2c_client * client,u8 address,char * values)205 static int sbs_read_string_data(struct i2c_client *client, u8 address,
206 				char *values)
207 {
208 	struct sbs_info *chip = i2c_get_clientdata(client);
209 	s32 ret = 0, block_length = 0;
210 	int retries_length, retries_block;
211 	u8 block_buffer[I2C_SMBUS_BLOCK_MAX + 1];
212 
213 	retries_length = chip->i2c_retry_count;
214 	retries_block = chip->i2c_retry_count;
215 
216 	/* Adapter needs to support these two functions */
217 	if (!i2c_check_functionality(client->adapter,
218 				     I2C_FUNC_SMBUS_BYTE_DATA |
219 				     I2C_FUNC_SMBUS_I2C_BLOCK)){
220 		return -ENODEV;
221 	}
222 
223 	/* Get the length of block data */
224 	while (retries_length > 0) {
225 		ret = i2c_smbus_read_byte_data(client, address);
226 		if (ret >= 0)
227 			break;
228 		retries_length--;
229 	}
230 
231 	if (ret < 0) {
232 		dev_dbg(&client->dev,
233 			"%s: i2c read at address 0x%x failed\n",
234 			__func__, address);
235 		return ret;
236 	}
237 
238 	/* block_length does not include NULL terminator */
239 	block_length = ret;
240 	if (block_length > I2C_SMBUS_BLOCK_MAX) {
241 		dev_err(&client->dev,
242 			"%s: Returned block_length is longer than 0x%x\n",
243 			__func__, I2C_SMBUS_BLOCK_MAX);
244 		return -EINVAL;
245 	}
246 
247 	/* Get the block data */
248 	while (retries_block > 0) {
249 		ret = i2c_smbus_read_i2c_block_data(
250 				client, address,
251 				block_length + 1, block_buffer);
252 		if (ret >= 0)
253 			break;
254 		retries_block--;
255 	}
256 
257 	if (ret < 0) {
258 		dev_dbg(&client->dev,
259 			"%s: i2c read at address 0x%x failed\n",
260 			__func__, address);
261 		return ret;
262 	}
263 
264 	/* block_buffer[0] == block_length */
265 	memcpy(values, block_buffer + 1, block_length);
266 	values[block_length] = '\0';
267 
268 	return ret;
269 }
270 
sbs_write_word_data(struct i2c_client * client,u8 address,u16 value)271 static int sbs_write_word_data(struct i2c_client *client, u8 address,
272 	u16 value)
273 {
274 	struct sbs_info *chip = i2c_get_clientdata(client);
275 	int retries = chip->i2c_retry_count;
276 	s32 ret = 0;
277 
278 	while (retries > 0) {
279 		ret = i2c_smbus_write_word_data(client, address, value);
280 		if (ret >= 0)
281 			break;
282 		retries--;
283 	}
284 
285 	if (ret < 0) {
286 		dev_dbg(&client->dev,
287 			"%s: i2c write to address 0x%x failed\n",
288 			__func__, address);
289 		return ret;
290 	}
291 
292 	return 0;
293 }
294 
sbs_status_correct(struct i2c_client * client,int * intval)295 static int sbs_status_correct(struct i2c_client *client, int *intval)
296 {
297 	int ret;
298 
299 	ret = sbs_read_word_data(client, sbs_data[REG_CURRENT].addr);
300 	if (ret < 0)
301 		return ret;
302 
303 	ret = (s16)ret;
304 
305 	/* Not drawing current means full (cannot be not charging) */
306 	if (ret == 0)
307 		*intval = POWER_SUPPLY_STATUS_FULL;
308 
309 	if (*intval == POWER_SUPPLY_STATUS_FULL) {
310 		/* Drawing or providing current when full */
311 		if (ret > 0)
312 			*intval = POWER_SUPPLY_STATUS_CHARGING;
313 		else if (ret < 0)
314 			*intval = POWER_SUPPLY_STATUS_DISCHARGING;
315 	}
316 
317 	return 0;
318 }
319 
sbs_get_battery_presence_and_health(struct i2c_client * client,enum power_supply_property psp,union power_supply_propval * val)320 static int sbs_get_battery_presence_and_health(
321 	struct i2c_client *client, enum power_supply_property psp,
322 	union power_supply_propval *val)
323 {
324 	int ret;
325 
326 	/* Dummy command; if it succeeds, battery is present. */
327 	ret = sbs_read_word_data(client, sbs_data[REG_STATUS].addr);
328 
329 	if (ret < 0) { /* battery not present*/
330 		if (psp == POWER_SUPPLY_PROP_PRESENT) {
331 			val->intval = 0;
332 			return 0;
333 		}
334 		return ret;
335 	}
336 
337 	if (psp == POWER_SUPPLY_PROP_PRESENT)
338 		val->intval = 1; /* battery present */
339 	else /* POWER_SUPPLY_PROP_HEALTH */
340 		/* SBS spec doesn't have a general health command. */
341 		val->intval = POWER_SUPPLY_HEALTH_UNKNOWN;
342 
343 	return 0;
344 }
345 
sbs_get_ti_battery_presence_and_health(struct i2c_client * client,enum power_supply_property psp,union power_supply_propval * val)346 static int sbs_get_ti_battery_presence_and_health(
347 	struct i2c_client *client, enum power_supply_property psp,
348 	union power_supply_propval *val)
349 {
350 	s32 ret;
351 
352 	/*
353 	 * Write to ManufacturerAccess with ManufacturerAccess command
354 	 * and then read the status.
355 	 */
356 	ret = sbs_write_word_data(client, sbs_data[REG_MANUFACTURER_DATA].addr,
357 				  MANUFACTURER_ACCESS_STATUS);
358 	if (ret < 0) {
359 		if (psp == POWER_SUPPLY_PROP_PRESENT)
360 			val->intval = 0; /* battery removed */
361 		return ret;
362 	}
363 
364 	ret = sbs_read_word_data(client, sbs_data[REG_MANUFACTURER_DATA].addr);
365 	if (ret < 0) {
366 		if (psp == POWER_SUPPLY_PROP_PRESENT)
367 			val->intval = 0; /* battery removed */
368 		return ret;
369 	}
370 
371 	if (ret < sbs_data[REG_MANUFACTURER_DATA].min_value ||
372 	    ret > sbs_data[REG_MANUFACTURER_DATA].max_value) {
373 		val->intval = 0;
374 		return 0;
375 	}
376 
377 	/* Mask the upper nibble of 2nd byte and
378 	 * lower byte of response then
379 	 * shift the result by 8 to get status*/
380 	ret &= 0x0F00;
381 	ret >>= 8;
382 	if (psp == POWER_SUPPLY_PROP_PRESENT) {
383 		if (ret == 0x0F)
384 			/* battery removed */
385 			val->intval = 0;
386 		else
387 			val->intval = 1;
388 	} else if (psp == POWER_SUPPLY_PROP_HEALTH) {
389 		if (ret == 0x09)
390 			val->intval = POWER_SUPPLY_HEALTH_UNSPEC_FAILURE;
391 		else if (ret == 0x0B)
392 			val->intval = POWER_SUPPLY_HEALTH_OVERHEAT;
393 		else if (ret == 0x0C)
394 			val->intval = POWER_SUPPLY_HEALTH_DEAD;
395 		else
396 			val->intval = POWER_SUPPLY_HEALTH_GOOD;
397 	}
398 
399 	return 0;
400 }
401 
sbs_get_battery_property(struct i2c_client * client,int reg_offset,enum power_supply_property psp,union power_supply_propval * val)402 static int sbs_get_battery_property(struct i2c_client *client,
403 	int reg_offset, enum power_supply_property psp,
404 	union power_supply_propval *val)
405 {
406 	struct sbs_info *chip = i2c_get_clientdata(client);
407 	s32 ret;
408 
409 	ret = sbs_read_word_data(client, sbs_data[reg_offset].addr);
410 	if (ret < 0)
411 		return ret;
412 
413 	/* returned values are 16 bit */
414 	if (sbs_data[reg_offset].min_value < 0)
415 		ret = (s16)ret;
416 
417 	if (ret >= sbs_data[reg_offset].min_value &&
418 	    ret <= sbs_data[reg_offset].max_value) {
419 		val->intval = ret;
420 		if (psp == POWER_SUPPLY_PROP_CAPACITY_LEVEL) {
421 			if (!(ret & BATTERY_INITIALIZED))
422 				val->intval =
423 					POWER_SUPPLY_CAPACITY_LEVEL_UNKNOWN;
424 			else if (ret & BATTERY_FULL_CHARGED)
425 				val->intval =
426 					POWER_SUPPLY_CAPACITY_LEVEL_FULL;
427 			else if (ret & BATTERY_FULL_DISCHARGED)
428 				val->intval =
429 					POWER_SUPPLY_CAPACITY_LEVEL_CRITICAL;
430 			else
431 				val->intval =
432 					POWER_SUPPLY_CAPACITY_LEVEL_NORMAL;
433 			return 0;
434 		} else if (psp != POWER_SUPPLY_PROP_STATUS) {
435 			return 0;
436 		}
437 
438 		if (ret & BATTERY_FULL_CHARGED)
439 			val->intval = POWER_SUPPLY_STATUS_FULL;
440 		else if (ret & BATTERY_DISCHARGING)
441 			val->intval = POWER_SUPPLY_STATUS_DISCHARGING;
442 		else
443 			val->intval = POWER_SUPPLY_STATUS_CHARGING;
444 
445 		sbs_status_correct(client, &val->intval);
446 
447 		if (chip->poll_time == 0)
448 			chip->last_state = val->intval;
449 		else if (chip->last_state != val->intval) {
450 			cancel_delayed_work_sync(&chip->work);
451 			power_supply_changed(chip->power_supply);
452 			chip->poll_time = 0;
453 		}
454 	} else {
455 		if (psp == POWER_SUPPLY_PROP_STATUS)
456 			val->intval = POWER_SUPPLY_STATUS_UNKNOWN;
457 		else if (psp == POWER_SUPPLY_PROP_CAPACITY)
458 			/* sbs spec says that this can be >100 %
459 			 * even if max value is 100 %
460 			 */
461 			val->intval = min(ret, 100);
462 		else
463 			val->intval = 0;
464 	}
465 
466 	return 0;
467 }
468 
sbs_get_battery_string_property(struct i2c_client * client,int reg_offset,enum power_supply_property psp,char * val)469 static int sbs_get_battery_string_property(struct i2c_client *client,
470 	int reg_offset, enum power_supply_property psp, char *val)
471 {
472 	s32 ret;
473 
474 	ret = sbs_read_string_data(client, sbs_data[reg_offset].addr, val);
475 
476 	if (ret < 0)
477 		return ret;
478 
479 	return 0;
480 }
481 
sbs_unit_adjustment(struct i2c_client * client,enum power_supply_property psp,union power_supply_propval * val)482 static void  sbs_unit_adjustment(struct i2c_client *client,
483 	enum power_supply_property psp, union power_supply_propval *val)
484 {
485 #define BASE_UNIT_CONVERSION		1000
486 #define BATTERY_MODE_CAP_MULT_WATT	(10 * BASE_UNIT_CONVERSION)
487 #define TIME_UNIT_CONVERSION		60
488 #define TEMP_KELVIN_TO_CELSIUS		2731
489 	switch (psp) {
490 	case POWER_SUPPLY_PROP_ENERGY_NOW:
491 	case POWER_SUPPLY_PROP_ENERGY_FULL:
492 	case POWER_SUPPLY_PROP_ENERGY_FULL_DESIGN:
493 		/* sbs provides energy in units of 10mWh.
494 		 * Convert to µWh
495 		 */
496 		val->intval *= BATTERY_MODE_CAP_MULT_WATT;
497 		break;
498 
499 	case POWER_SUPPLY_PROP_VOLTAGE_NOW:
500 	case POWER_SUPPLY_PROP_VOLTAGE_MIN_DESIGN:
501 	case POWER_SUPPLY_PROP_VOLTAGE_MAX_DESIGN:
502 	case POWER_SUPPLY_PROP_CURRENT_NOW:
503 	case POWER_SUPPLY_PROP_CHARGE_NOW:
504 	case POWER_SUPPLY_PROP_CHARGE_FULL:
505 	case POWER_SUPPLY_PROP_CHARGE_FULL_DESIGN:
506 		val->intval *= BASE_UNIT_CONVERSION;
507 		break;
508 
509 	case POWER_SUPPLY_PROP_TEMP:
510 		/* sbs provides battery temperature in 0.1K
511 		 * so convert it to 0.1°C
512 		 */
513 		val->intval -= TEMP_KELVIN_TO_CELSIUS;
514 		break;
515 
516 	case POWER_SUPPLY_PROP_TIME_TO_EMPTY_AVG:
517 	case POWER_SUPPLY_PROP_TIME_TO_FULL_AVG:
518 		/* sbs provides time to empty and time to full in minutes.
519 		 * Convert to seconds
520 		 */
521 		val->intval *= TIME_UNIT_CONVERSION;
522 		break;
523 
524 	default:
525 		dev_dbg(&client->dev,
526 			"%s: no need for unit conversion %d\n", __func__, psp);
527 	}
528 }
529 
sbs_set_battery_mode(struct i2c_client * client,enum sbs_battery_mode mode)530 static enum sbs_battery_mode sbs_set_battery_mode(struct i2c_client *client,
531 	enum sbs_battery_mode mode)
532 {
533 	int ret, original_val;
534 
535 	original_val = sbs_read_word_data(client, BATTERY_MODE_OFFSET);
536 	if (original_val < 0)
537 		return original_val;
538 
539 	if ((original_val & BATTERY_MODE_MASK) == mode)
540 		return mode;
541 
542 	if (mode == BATTERY_MODE_AMPS)
543 		ret = original_val & ~BATTERY_MODE_MASK;
544 	else
545 		ret = original_val | BATTERY_MODE_MASK;
546 
547 	ret = sbs_write_word_data(client, BATTERY_MODE_OFFSET, ret);
548 	if (ret < 0)
549 		return ret;
550 
551 	usleep_range(1000, 2000);
552 
553 	return original_val & BATTERY_MODE_MASK;
554 }
555 
sbs_get_battery_capacity(struct i2c_client * client,int reg_offset,enum power_supply_property psp,union power_supply_propval * val)556 static int sbs_get_battery_capacity(struct i2c_client *client,
557 	int reg_offset, enum power_supply_property psp,
558 	union power_supply_propval *val)
559 {
560 	s32 ret;
561 	enum sbs_battery_mode mode = BATTERY_MODE_WATTS;
562 
563 	if (power_supply_is_amp_property(psp))
564 		mode = BATTERY_MODE_AMPS;
565 
566 	mode = sbs_set_battery_mode(client, mode);
567 	if (mode < 0)
568 		return mode;
569 
570 	ret = sbs_read_word_data(client, sbs_data[reg_offset].addr);
571 	if (ret < 0)
572 		return ret;
573 
574 	val->intval = ret;
575 
576 	ret = sbs_set_battery_mode(client, mode);
577 	if (ret < 0)
578 		return ret;
579 
580 	return 0;
581 }
582 
583 static char sbs_serial[5];
sbs_get_battery_serial_number(struct i2c_client * client,union power_supply_propval * val)584 static int sbs_get_battery_serial_number(struct i2c_client *client,
585 	union power_supply_propval *val)
586 {
587 	int ret;
588 
589 	ret = sbs_read_word_data(client, sbs_data[REG_SERIAL_NUMBER].addr);
590 	if (ret < 0)
591 		return ret;
592 
593 	sprintf(sbs_serial, "%04x", ret);
594 	val->strval = sbs_serial;
595 
596 	return 0;
597 }
598 
sbs_get_property_index(struct i2c_client * client,enum power_supply_property psp)599 static int sbs_get_property_index(struct i2c_client *client,
600 	enum power_supply_property psp)
601 {
602 	int count;
603 	for (count = 0; count < ARRAY_SIZE(sbs_data); count++)
604 		if (psp == sbs_data[count].psp)
605 			return count;
606 
607 	dev_warn(&client->dev,
608 		"%s: Invalid Property - %d\n", __func__, psp);
609 
610 	return -EINVAL;
611 }
612 
sbs_get_property(struct power_supply * psy,enum power_supply_property psp,union power_supply_propval * val)613 static int sbs_get_property(struct power_supply *psy,
614 	enum power_supply_property psp,
615 	union power_supply_propval *val)
616 {
617 	int ret = 0;
618 	struct sbs_info *chip = power_supply_get_drvdata(psy);
619 	struct i2c_client *client = chip->client;
620 
621 	if (chip->gpio_detect) {
622 		ret = gpiod_get_value_cansleep(chip->gpio_detect);
623 		if (ret < 0)
624 			return ret;
625 		if (psp == POWER_SUPPLY_PROP_PRESENT) {
626 			val->intval = ret;
627 			chip->is_present = val->intval;
628 			return 0;
629 		}
630 		if (ret == 0)
631 			return -ENODATA;
632 	}
633 
634 	switch (psp) {
635 	case POWER_SUPPLY_PROP_PRESENT:
636 	case POWER_SUPPLY_PROP_HEALTH:
637 		if (chip->flags & SBS_FLAGS_TI_BQ20Z75)
638 			ret = sbs_get_ti_battery_presence_and_health(client,
639 								     psp, val);
640 		else
641 			ret = sbs_get_battery_presence_and_health(client, psp,
642 								  val);
643 
644 		/* this can only be true if no gpio is used */
645 		if (psp == POWER_SUPPLY_PROP_PRESENT)
646 			return 0;
647 		break;
648 
649 	case POWER_SUPPLY_PROP_TECHNOLOGY:
650 		val->intval = POWER_SUPPLY_TECHNOLOGY_LION;
651 		goto done; /* don't trigger power_supply_changed()! */
652 
653 	case POWER_SUPPLY_PROP_ENERGY_NOW:
654 	case POWER_SUPPLY_PROP_ENERGY_FULL:
655 	case POWER_SUPPLY_PROP_ENERGY_FULL_DESIGN:
656 	case POWER_SUPPLY_PROP_CHARGE_NOW:
657 	case POWER_SUPPLY_PROP_CHARGE_FULL:
658 	case POWER_SUPPLY_PROP_CHARGE_FULL_DESIGN:
659 		ret = sbs_get_property_index(client, psp);
660 		if (ret < 0)
661 			break;
662 
663 		/* sbs_get_battery_capacity() will change the battery mode
664 		 * temporarily to read the requested attribute. Ensure we stay
665 		 * in the desired mode for the duration of the attribute read.
666 		 */
667 		mutex_lock(&chip->mode_lock);
668 		ret = sbs_get_battery_capacity(client, ret, psp, val);
669 		mutex_unlock(&chip->mode_lock);
670 		break;
671 
672 	case POWER_SUPPLY_PROP_SERIAL_NUMBER:
673 		ret = sbs_get_battery_serial_number(client, val);
674 		break;
675 
676 	case POWER_SUPPLY_PROP_STATUS:
677 	case POWER_SUPPLY_PROP_CAPACITY_LEVEL:
678 	case POWER_SUPPLY_PROP_CYCLE_COUNT:
679 	case POWER_SUPPLY_PROP_VOLTAGE_NOW:
680 	case POWER_SUPPLY_PROP_CURRENT_NOW:
681 	case POWER_SUPPLY_PROP_TEMP:
682 	case POWER_SUPPLY_PROP_TIME_TO_EMPTY_AVG:
683 	case POWER_SUPPLY_PROP_TIME_TO_FULL_AVG:
684 	case POWER_SUPPLY_PROP_VOLTAGE_MIN_DESIGN:
685 	case POWER_SUPPLY_PROP_VOLTAGE_MAX_DESIGN:
686 	case POWER_SUPPLY_PROP_CAPACITY:
687 		ret = sbs_get_property_index(client, psp);
688 		if (ret < 0)
689 			break;
690 
691 		ret = sbs_get_battery_property(client, ret, psp, val);
692 		break;
693 
694 	case POWER_SUPPLY_PROP_MODEL_NAME:
695 		ret = sbs_get_property_index(client, psp);
696 		if (ret < 0)
697 			break;
698 
699 		ret = sbs_get_battery_string_property(client, ret, psp,
700 						      model_name);
701 		val->strval = model_name;
702 		break;
703 
704 	case POWER_SUPPLY_PROP_MANUFACTURER:
705 		ret = sbs_get_property_index(client, psp);
706 		if (ret < 0)
707 			break;
708 
709 		ret = sbs_get_battery_string_property(client, ret, psp,
710 						      manufacturer);
711 		val->strval = manufacturer;
712 		break;
713 
714 	default:
715 		dev_err(&client->dev,
716 			"%s: INVALID property\n", __func__);
717 		return -EINVAL;
718 	}
719 
720 	if (!chip->enable_detection)
721 		goto done;
722 
723 	if (!chip->gpio_detect &&
724 		chip->is_present != (ret >= 0)) {
725 		chip->is_present = (ret >= 0);
726 		power_supply_changed(chip->power_supply);
727 	}
728 
729 done:
730 	if (!ret) {
731 		/* Convert units to match requirements for power supply class */
732 		sbs_unit_adjustment(client, psp, val);
733 	}
734 
735 	dev_dbg(&client->dev,
736 		"%s: property = %d, value = %x\n", __func__, psp, val->intval);
737 
738 	if (ret && chip->is_present)
739 		return ret;
740 
741 	/* battery not present, so return NODATA for properties */
742 	if (ret)
743 		return -ENODATA;
744 
745 	return 0;
746 }
747 
sbs_supply_changed(struct sbs_info * chip)748 static void sbs_supply_changed(struct sbs_info *chip)
749 {
750 	struct power_supply *battery = chip->power_supply;
751 	int ret;
752 
753 	ret = gpiod_get_value_cansleep(chip->gpio_detect);
754 	if (ret < 0)
755 		return;
756 	chip->is_present = ret;
757 	power_supply_changed(battery);
758 }
759 
sbs_irq(int irq,void * devid)760 static irqreturn_t sbs_irq(int irq, void *devid)
761 {
762 	sbs_supply_changed(devid);
763 	return IRQ_HANDLED;
764 }
765 
sbs_alert(struct i2c_client * client,enum i2c_alert_protocol prot,unsigned int data)766 static void sbs_alert(struct i2c_client *client, enum i2c_alert_protocol prot,
767 	unsigned int data)
768 {
769 	sbs_supply_changed(i2c_get_clientdata(client));
770 }
771 
sbs_external_power_changed(struct power_supply * psy)772 static void sbs_external_power_changed(struct power_supply *psy)
773 {
774 	struct sbs_info *chip = power_supply_get_drvdata(psy);
775 
776 	/* cancel outstanding work */
777 	cancel_delayed_work_sync(&chip->work);
778 
779 	schedule_delayed_work(&chip->work, HZ);
780 	chip->poll_time = chip->poll_retry_count;
781 }
782 
sbs_delayed_work(struct work_struct * work)783 static void sbs_delayed_work(struct work_struct *work)
784 {
785 	struct sbs_info *chip;
786 	s32 ret;
787 
788 	chip = container_of(work, struct sbs_info, work.work);
789 
790 	ret = sbs_read_word_data(chip->client, sbs_data[REG_STATUS].addr);
791 	/* if the read failed, give up on this work */
792 	if (ret < 0) {
793 		chip->poll_time = 0;
794 		return;
795 	}
796 
797 	if (ret & BATTERY_FULL_CHARGED)
798 		ret = POWER_SUPPLY_STATUS_FULL;
799 	else if (ret & BATTERY_DISCHARGING)
800 		ret = POWER_SUPPLY_STATUS_DISCHARGING;
801 	else
802 		ret = POWER_SUPPLY_STATUS_CHARGING;
803 
804 	sbs_status_correct(chip->client, &ret);
805 
806 	if (chip->last_state != ret) {
807 		chip->poll_time = 0;
808 		power_supply_changed(chip->power_supply);
809 		return;
810 	}
811 	if (chip->poll_time > 0) {
812 		schedule_delayed_work(&chip->work, HZ);
813 		chip->poll_time--;
814 		return;
815 	}
816 }
817 
818 static const struct power_supply_desc sbs_default_desc = {
819 	.type = POWER_SUPPLY_TYPE_BATTERY,
820 	.properties = sbs_properties,
821 	.num_properties = ARRAY_SIZE(sbs_properties),
822 	.get_property = sbs_get_property,
823 	.external_power_changed = sbs_external_power_changed,
824 };
825 
sbs_probe(struct i2c_client * client,const struct i2c_device_id * id)826 static int sbs_probe(struct i2c_client *client,
827 	const struct i2c_device_id *id)
828 {
829 	struct sbs_info *chip;
830 	struct power_supply_desc *sbs_desc;
831 	struct sbs_platform_data *pdata = client->dev.platform_data;
832 	struct power_supply_config psy_cfg = {};
833 	int rc;
834 	int irq;
835 
836 	sbs_desc = devm_kmemdup(&client->dev, &sbs_default_desc,
837 			sizeof(*sbs_desc), GFP_KERNEL);
838 	if (!sbs_desc)
839 		return -ENOMEM;
840 
841 	sbs_desc->name = devm_kasprintf(&client->dev, GFP_KERNEL, "sbs-%s",
842 			dev_name(&client->dev));
843 	if (!sbs_desc->name)
844 		return -ENOMEM;
845 
846 	chip = devm_kzalloc(&client->dev, sizeof(struct sbs_info), GFP_KERNEL);
847 	if (!chip)
848 		return -ENOMEM;
849 
850 	chip->flags = (u32)(uintptr_t)of_device_get_match_data(&client->dev);
851 	chip->client = client;
852 	chip->enable_detection = false;
853 	psy_cfg.of_node = client->dev.of_node;
854 	psy_cfg.drv_data = chip;
855 	chip->last_state = POWER_SUPPLY_STATUS_UNKNOWN;
856 	mutex_init(&chip->mode_lock);
857 
858 	/* use pdata if available, fall back to DT properties,
859 	 * or hardcoded defaults if not
860 	 */
861 	rc = of_property_read_u32(client->dev.of_node, "sbs,i2c-retry-count",
862 				  &chip->i2c_retry_count);
863 	if (rc)
864 		chip->i2c_retry_count = 0;
865 
866 	rc = of_property_read_u32(client->dev.of_node, "sbs,poll-retry-count",
867 				  &chip->poll_retry_count);
868 	if (rc)
869 		chip->poll_retry_count = 0;
870 
871 	if (pdata) {
872 		chip->poll_retry_count = pdata->poll_retry_count;
873 		chip->i2c_retry_count  = pdata->i2c_retry_count;
874 	}
875 	chip->i2c_retry_count = chip->i2c_retry_count + 1;
876 
877 	chip->gpio_detect = devm_gpiod_get_optional(&client->dev,
878 			"sbs,battery-detect", GPIOD_IN);
879 	if (IS_ERR(chip->gpio_detect)) {
880 		dev_err(&client->dev, "Failed to get gpio: %ld\n",
881 			PTR_ERR(chip->gpio_detect));
882 		return PTR_ERR(chip->gpio_detect);
883 	}
884 
885 	i2c_set_clientdata(client, chip);
886 
887 	if (!chip->gpio_detect)
888 		goto skip_gpio;
889 
890 	irq = gpiod_to_irq(chip->gpio_detect);
891 	if (irq <= 0) {
892 		dev_warn(&client->dev, "Failed to get gpio as irq: %d\n", irq);
893 		goto skip_gpio;
894 	}
895 
896 	rc = devm_request_threaded_irq(&client->dev, irq, NULL, sbs_irq,
897 		IRQF_TRIGGER_RISING | IRQF_TRIGGER_FALLING | IRQF_ONESHOT,
898 		dev_name(&client->dev), chip);
899 	if (rc) {
900 		dev_warn(&client->dev, "Failed to request irq: %d\n", rc);
901 		goto skip_gpio;
902 	}
903 
904 skip_gpio:
905 	/*
906 	 * Before we register, we might need to make sure we can actually talk
907 	 * to the battery.
908 	 */
909 	if (!(force_load || chip->gpio_detect)) {
910 		rc = sbs_read_word_data(client, sbs_data[REG_STATUS].addr);
911 
912 		if (rc < 0) {
913 			dev_err(&client->dev, "%s: Failed to get device status\n",
914 				__func__);
915 			goto exit_psupply;
916 		}
917 	}
918 
919 	chip->power_supply = devm_power_supply_register(&client->dev, sbs_desc,
920 						   &psy_cfg);
921 	if (IS_ERR(chip->power_supply)) {
922 		dev_err(&client->dev,
923 			"%s: Failed to register power supply\n", __func__);
924 		rc = PTR_ERR(chip->power_supply);
925 		goto exit_psupply;
926 	}
927 
928 	dev_info(&client->dev,
929 		"%s: battery gas gauge device registered\n", client->name);
930 
931 	INIT_DELAYED_WORK(&chip->work, sbs_delayed_work);
932 
933 	chip->enable_detection = true;
934 
935 	return 0;
936 
937 exit_psupply:
938 	return rc;
939 }
940 
sbs_remove(struct i2c_client * client)941 static int sbs_remove(struct i2c_client *client)
942 {
943 	struct sbs_info *chip = i2c_get_clientdata(client);
944 
945 	cancel_delayed_work_sync(&chip->work);
946 
947 	return 0;
948 }
949 
950 #if defined CONFIG_PM_SLEEP
951 
sbs_suspend(struct device * dev)952 static int sbs_suspend(struct device *dev)
953 {
954 	struct i2c_client *client = to_i2c_client(dev);
955 	struct sbs_info *chip = i2c_get_clientdata(client);
956 	int ret;
957 
958 	if (chip->poll_time > 0)
959 		cancel_delayed_work_sync(&chip->work);
960 
961 	if (chip->flags & SBS_FLAGS_TI_BQ20Z75) {
962 		/* Write to manufacturer access with sleep command. */
963 		ret = sbs_write_word_data(client,
964 					  sbs_data[REG_MANUFACTURER_DATA].addr,
965 					  MANUFACTURER_ACCESS_SLEEP);
966 		if (chip->is_present && ret < 0)
967 			return ret;
968 	}
969 
970 	return 0;
971 }
972 
973 static SIMPLE_DEV_PM_OPS(sbs_pm_ops, sbs_suspend, NULL);
974 #define SBS_PM_OPS (&sbs_pm_ops)
975 
976 #else
977 #define SBS_PM_OPS NULL
978 #endif
979 
980 static const struct i2c_device_id sbs_id[] = {
981 	{ "bq20z75", 0 },
982 	{ "sbs-battery", 1 },
983 	{}
984 };
985 MODULE_DEVICE_TABLE(i2c, sbs_id);
986 
987 static const struct of_device_id sbs_dt_ids[] = {
988 	{ .compatible = "sbs,sbs-battery" },
989 	{
990 		.compatible = "ti,bq20z75",
991 		.data = (void *)SBS_FLAGS_TI_BQ20Z75,
992 	},
993 	{ }
994 };
995 MODULE_DEVICE_TABLE(of, sbs_dt_ids);
996 
997 static struct i2c_driver sbs_battery_driver = {
998 	.probe		= sbs_probe,
999 	.remove		= sbs_remove,
1000 	.alert		= sbs_alert,
1001 	.id_table	= sbs_id,
1002 	.driver = {
1003 		.name	= "sbs-battery",
1004 		.of_match_table = sbs_dt_ids,
1005 		.pm	= SBS_PM_OPS,
1006 	},
1007 };
1008 module_i2c_driver(sbs_battery_driver);
1009 
1010 MODULE_DESCRIPTION("SBS battery monitor driver");
1011 MODULE_LICENSE("GPL");
1012 
1013 module_param(force_load, bool, S_IRUSR | S_IRGRP | S_IROTH);
1014 MODULE_PARM_DESC(force_load,
1015 		 "Attempt to load the driver even if no battery is connected");
1016