1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * axp288_fuel_gauge.c - Xpower AXP288 PMIC Fuel Gauge Driver
4  *
5  * Copyright (C) 2016-2017 Hans de Goede <hdegoede@redhat.com>
6  * Copyright (C) 2014 Intel Corporation
7  *
8  * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
9  */
10 
11 #include <linux/dmi.h>
12 #include <linux/module.h>
13 #include <linux/kernel.h>
14 #include <linux/device.h>
15 #include <linux/regmap.h>
16 #include <linux/jiffies.h>
17 #include <linux/interrupt.h>
18 #include <linux/mfd/axp20x.h>
19 #include <linux/platform_device.h>
20 #include <linux/power_supply.h>
21 #include <linux/iio/consumer.h>
22 #include <linux/debugfs.h>
23 #include <linux/seq_file.h>
24 #include <asm/unaligned.h>
25 
26 #define PS_STAT_VBUS_TRIGGER		(1 << 0)
27 #define PS_STAT_BAT_CHRG_DIR		(1 << 2)
28 #define PS_STAT_VBAT_ABOVE_VHOLD	(1 << 3)
29 #define PS_STAT_VBUS_VALID		(1 << 4)
30 #define PS_STAT_VBUS_PRESENT		(1 << 5)
31 
32 #define CHRG_STAT_BAT_SAFE_MODE		(1 << 3)
33 #define CHRG_STAT_BAT_VALID			(1 << 4)
34 #define CHRG_STAT_BAT_PRESENT		(1 << 5)
35 #define CHRG_STAT_CHARGING			(1 << 6)
36 #define CHRG_STAT_PMIC_OTP			(1 << 7)
37 
38 #define CHRG_CCCV_CC_MASK			0xf     /* 4 bits */
39 #define CHRG_CCCV_CC_BIT_POS		0
40 #define CHRG_CCCV_CC_OFFSET			200     /* 200mA */
41 #define CHRG_CCCV_CC_LSB_RES		200     /* 200mA */
42 #define CHRG_CCCV_ITERM_20P			(1 << 4)    /* 20% of CC */
43 #define CHRG_CCCV_CV_MASK			0x60        /* 2 bits */
44 #define CHRG_CCCV_CV_BIT_POS		5
45 #define CHRG_CCCV_CV_4100MV			0x0     /* 4.10V */
46 #define CHRG_CCCV_CV_4150MV			0x1     /* 4.15V */
47 #define CHRG_CCCV_CV_4200MV			0x2     /* 4.20V */
48 #define CHRG_CCCV_CV_4350MV			0x3     /* 4.35V */
49 #define CHRG_CCCV_CHG_EN			(1 << 7)
50 
51 #define FG_CNTL_OCV_ADJ_STAT		(1 << 2)
52 #define FG_CNTL_OCV_ADJ_EN			(1 << 3)
53 #define FG_CNTL_CAP_ADJ_STAT		(1 << 4)
54 #define FG_CNTL_CAP_ADJ_EN			(1 << 5)
55 #define FG_CNTL_CC_EN				(1 << 6)
56 #define FG_CNTL_GAUGE_EN			(1 << 7)
57 
58 #define FG_15BIT_WORD_VALID			(1 << 15)
59 #define FG_15BIT_VAL_MASK			0x7fff
60 
61 #define FG_REP_CAP_VALID			(1 << 7)
62 #define FG_REP_CAP_VAL_MASK			0x7F
63 
64 #define FG_DES_CAP1_VALID			(1 << 7)
65 #define FG_DES_CAP_RES_LSB			1456    /* 1.456mAhr */
66 
67 #define FG_DES_CC_RES_LSB			1456    /* 1.456mAhr */
68 
69 #define FG_OCV_CAP_VALID			(1 << 7)
70 #define FG_OCV_CAP_VAL_MASK			0x7F
71 #define FG_CC_CAP_VALID				(1 << 7)
72 #define FG_CC_CAP_VAL_MASK			0x7F
73 
74 #define FG_LOW_CAP_THR1_MASK		0xf0    /* 5% tp 20% */
75 #define FG_LOW_CAP_THR1_VAL			0xa0    /* 15 perc */
76 #define FG_LOW_CAP_THR2_MASK		0x0f    /* 0% to 15% */
77 #define FG_LOW_CAP_WARN_THR			14  /* 14 perc */
78 #define FG_LOW_CAP_CRIT_THR			4   /* 4 perc */
79 #define FG_LOW_CAP_SHDN_THR			0   /* 0 perc */
80 
81 #define NR_RETRY_CNT    3
82 #define DEV_NAME	"axp288_fuel_gauge"
83 
84 /* 1.1mV per LSB expressed in uV */
85 #define VOLTAGE_FROM_ADC(a)			((a * 11) / 10)
86 /* properties converted to uV, uA */
87 #define PROP_VOLT(a)		((a) * 1000)
88 #define PROP_CURR(a)		((a) * 1000)
89 
90 #define AXP288_FG_INTR_NUM	6
91 enum {
92 	QWBTU_IRQ = 0,
93 	WBTU_IRQ,
94 	QWBTO_IRQ,
95 	WBTO_IRQ,
96 	WL2_IRQ,
97 	WL1_IRQ,
98 };
99 
100 enum {
101 	BAT_TEMP = 0,
102 	PMIC_TEMP,
103 	SYSTEM_TEMP,
104 	BAT_CHRG_CURR,
105 	BAT_D_CURR,
106 	BAT_VOLT,
107 	IIO_CHANNEL_NUM
108 };
109 
110 struct axp288_fg_info {
111 	struct platform_device *pdev;
112 	struct regmap *regmap;
113 	struct regmap_irq_chip_data *regmap_irqc;
114 	int irq[AXP288_FG_INTR_NUM];
115 	struct iio_channel *iio_channel[IIO_CHANNEL_NUM];
116 	struct power_supply *bat;
117 	struct mutex lock;
118 	int status;
119 	int max_volt;
120 	struct dentry *debug_file;
121 };
122 
123 static enum power_supply_property fuel_gauge_props[] = {
124 	POWER_SUPPLY_PROP_STATUS,
125 	POWER_SUPPLY_PROP_PRESENT,
126 	POWER_SUPPLY_PROP_HEALTH,
127 	POWER_SUPPLY_PROP_VOLTAGE_MAX_DESIGN,
128 	POWER_SUPPLY_PROP_VOLTAGE_NOW,
129 	POWER_SUPPLY_PROP_VOLTAGE_OCV,
130 	POWER_SUPPLY_PROP_CURRENT_NOW,
131 	POWER_SUPPLY_PROP_CAPACITY,
132 	POWER_SUPPLY_PROP_CAPACITY_ALERT_MIN,
133 	POWER_SUPPLY_PROP_TECHNOLOGY,
134 	POWER_SUPPLY_PROP_CHARGE_FULL,
135 	POWER_SUPPLY_PROP_CHARGE_NOW,
136 };
137 
138 static int fuel_gauge_reg_readb(struct axp288_fg_info *info, int reg)
139 {
140 	int ret, i;
141 	unsigned int val;
142 
143 	for (i = 0; i < NR_RETRY_CNT; i++) {
144 		ret = regmap_read(info->regmap, reg, &val);
145 		if (ret == -EBUSY)
146 			continue;
147 		else
148 			break;
149 	}
150 
151 	if (ret < 0) {
152 		dev_err(&info->pdev->dev, "axp288 reg read err:%d\n", ret);
153 		return ret;
154 	}
155 
156 	return val;
157 }
158 
159 static int fuel_gauge_reg_writeb(struct axp288_fg_info *info, int reg, u8 val)
160 {
161 	int ret;
162 
163 	ret = regmap_write(info->regmap, reg, (unsigned int)val);
164 
165 	if (ret < 0)
166 		dev_err(&info->pdev->dev, "axp288 reg write err:%d\n", ret);
167 
168 	return ret;
169 }
170 
171 static int fuel_gauge_read_15bit_word(struct axp288_fg_info *info, int reg)
172 {
173 	unsigned char buf[2];
174 	int ret;
175 
176 	ret = regmap_bulk_read(info->regmap, reg, buf, 2);
177 	if (ret < 0) {
178 		dev_err(&info->pdev->dev, "Error reading reg 0x%02x err: %d\n",
179 			reg, ret);
180 		return ret;
181 	}
182 
183 	ret = get_unaligned_be16(buf);
184 	if (!(ret & FG_15BIT_WORD_VALID)) {
185 		dev_err(&info->pdev->dev, "Error reg 0x%02x contents not valid\n",
186 			reg);
187 		return -ENXIO;
188 	}
189 
190 	return ret & FG_15BIT_VAL_MASK;
191 }
192 
193 static int fuel_gauge_read_12bit_word(struct axp288_fg_info *info, int reg)
194 {
195 	unsigned char buf[2];
196 	int ret;
197 
198 	ret = regmap_bulk_read(info->regmap, reg, buf, 2);
199 	if (ret < 0) {
200 		dev_err(&info->pdev->dev, "Error reading reg 0x%02x err: %d\n",
201 			reg, ret);
202 		return ret;
203 	}
204 
205 	/* 12-bit data values have upper 8 bits in buf[0], lower 4 in buf[1] */
206 	return (buf[0] << 4) | ((buf[1] >> 4) & 0x0f);
207 }
208 
209 #ifdef CONFIG_DEBUG_FS
210 static int fuel_gauge_debug_show(struct seq_file *s, void *data)
211 {
212 	struct axp288_fg_info *info = s->private;
213 	int raw_val, ret;
214 
215 	seq_printf(s, " PWR_STATUS[%02x] : %02x\n",
216 		AXP20X_PWR_INPUT_STATUS,
217 		fuel_gauge_reg_readb(info, AXP20X_PWR_INPUT_STATUS));
218 	seq_printf(s, "PWR_OP_MODE[%02x] : %02x\n",
219 		AXP20X_PWR_OP_MODE,
220 		fuel_gauge_reg_readb(info, AXP20X_PWR_OP_MODE));
221 	seq_printf(s, " CHRG_CTRL1[%02x] : %02x\n",
222 		AXP20X_CHRG_CTRL1,
223 		fuel_gauge_reg_readb(info, AXP20X_CHRG_CTRL1));
224 	seq_printf(s, "       VLTF[%02x] : %02x\n",
225 		AXP20X_V_LTF_DISCHRG,
226 		fuel_gauge_reg_readb(info, AXP20X_V_LTF_DISCHRG));
227 	seq_printf(s, "       VHTF[%02x] : %02x\n",
228 		AXP20X_V_HTF_DISCHRG,
229 		fuel_gauge_reg_readb(info, AXP20X_V_HTF_DISCHRG));
230 	seq_printf(s, "    CC_CTRL[%02x] : %02x\n",
231 		AXP20X_CC_CTRL,
232 		fuel_gauge_reg_readb(info, AXP20X_CC_CTRL));
233 	seq_printf(s, "BATTERY CAP[%02x] : %02x\n",
234 		AXP20X_FG_RES,
235 		fuel_gauge_reg_readb(info, AXP20X_FG_RES));
236 	seq_printf(s, "    FG_RDC1[%02x] : %02x\n",
237 		AXP288_FG_RDC1_REG,
238 		fuel_gauge_reg_readb(info, AXP288_FG_RDC1_REG));
239 	seq_printf(s, "    FG_RDC0[%02x] : %02x\n",
240 		AXP288_FG_RDC0_REG,
241 		fuel_gauge_reg_readb(info, AXP288_FG_RDC0_REG));
242 	seq_printf(s, "     FG_OCV[%02x] : %04x\n",
243 		AXP288_FG_OCVH_REG,
244 		fuel_gauge_read_12bit_word(info, AXP288_FG_OCVH_REG));
245 	seq_printf(s, " FG_DES_CAP[%02x] : %04x\n",
246 		AXP288_FG_DES_CAP1_REG,
247 		fuel_gauge_read_15bit_word(info, AXP288_FG_DES_CAP1_REG));
248 	seq_printf(s, "  FG_CC_MTR[%02x] : %04x\n",
249 		AXP288_FG_CC_MTR1_REG,
250 		fuel_gauge_read_15bit_word(info, AXP288_FG_CC_MTR1_REG));
251 	seq_printf(s, " FG_OCV_CAP[%02x] : %02x\n",
252 		AXP288_FG_OCV_CAP_REG,
253 		fuel_gauge_reg_readb(info, AXP288_FG_OCV_CAP_REG));
254 	seq_printf(s, "  FG_CC_CAP[%02x] : %02x\n",
255 		AXP288_FG_CC_CAP_REG,
256 		fuel_gauge_reg_readb(info, AXP288_FG_CC_CAP_REG));
257 	seq_printf(s, " FG_LOW_CAP[%02x] : %02x\n",
258 		AXP288_FG_LOW_CAP_REG,
259 		fuel_gauge_reg_readb(info, AXP288_FG_LOW_CAP_REG));
260 	seq_printf(s, "TUNING_CTL0[%02x] : %02x\n",
261 		AXP288_FG_TUNE0,
262 		fuel_gauge_reg_readb(info, AXP288_FG_TUNE0));
263 	seq_printf(s, "TUNING_CTL1[%02x] : %02x\n",
264 		AXP288_FG_TUNE1,
265 		fuel_gauge_reg_readb(info, AXP288_FG_TUNE1));
266 	seq_printf(s, "TUNING_CTL2[%02x] : %02x\n",
267 		AXP288_FG_TUNE2,
268 		fuel_gauge_reg_readb(info, AXP288_FG_TUNE2));
269 	seq_printf(s, "TUNING_CTL3[%02x] : %02x\n",
270 		AXP288_FG_TUNE3,
271 		fuel_gauge_reg_readb(info, AXP288_FG_TUNE3));
272 	seq_printf(s, "TUNING_CTL4[%02x] : %02x\n",
273 		AXP288_FG_TUNE4,
274 		fuel_gauge_reg_readb(info, AXP288_FG_TUNE4));
275 	seq_printf(s, "TUNING_CTL5[%02x] : %02x\n",
276 		AXP288_FG_TUNE5,
277 		fuel_gauge_reg_readb(info, AXP288_FG_TUNE5));
278 
279 	ret = iio_read_channel_raw(info->iio_channel[BAT_TEMP], &raw_val);
280 	if (ret >= 0)
281 		seq_printf(s, "axp288-batttemp : %d\n", raw_val);
282 	ret = iio_read_channel_raw(info->iio_channel[PMIC_TEMP], &raw_val);
283 	if (ret >= 0)
284 		seq_printf(s, "axp288-pmictemp : %d\n", raw_val);
285 	ret = iio_read_channel_raw(info->iio_channel[SYSTEM_TEMP], &raw_val);
286 	if (ret >= 0)
287 		seq_printf(s, "axp288-systtemp : %d\n", raw_val);
288 	ret = iio_read_channel_raw(info->iio_channel[BAT_CHRG_CURR], &raw_val);
289 	if (ret >= 0)
290 		seq_printf(s, "axp288-chrgcurr : %d\n", raw_val);
291 	ret = iio_read_channel_raw(info->iio_channel[BAT_D_CURR], &raw_val);
292 	if (ret >= 0)
293 		seq_printf(s, "axp288-dchrgcur : %d\n", raw_val);
294 	ret = iio_read_channel_raw(info->iio_channel[BAT_VOLT], &raw_val);
295 	if (ret >= 0)
296 		seq_printf(s, "axp288-battvolt : %d\n", raw_val);
297 
298 	return 0;
299 }
300 
301 DEFINE_SHOW_ATTRIBUTE(fuel_gauge_debug);
302 
303 static void fuel_gauge_create_debugfs(struct axp288_fg_info *info)
304 {
305 	info->debug_file = debugfs_create_file("fuelgauge", 0666, NULL,
306 		info, &fuel_gauge_debug_fops);
307 }
308 
309 static void fuel_gauge_remove_debugfs(struct axp288_fg_info *info)
310 {
311 	debugfs_remove(info->debug_file);
312 }
313 #else
314 static inline void fuel_gauge_create_debugfs(struct axp288_fg_info *info)
315 {
316 }
317 static inline void fuel_gauge_remove_debugfs(struct axp288_fg_info *info)
318 {
319 }
320 #endif
321 
322 static void fuel_gauge_get_status(struct axp288_fg_info *info)
323 {
324 	int pwr_stat, fg_res, curr, ret;
325 
326 	pwr_stat = fuel_gauge_reg_readb(info, AXP20X_PWR_INPUT_STATUS);
327 	if (pwr_stat < 0) {
328 		dev_err(&info->pdev->dev,
329 			"PWR STAT read failed:%d\n", pwr_stat);
330 		return;
331 	}
332 
333 	/* Report full if Vbus is valid and the reported capacity is 100% */
334 	if (!(pwr_stat & PS_STAT_VBUS_VALID))
335 		goto not_full;
336 
337 	fg_res = fuel_gauge_reg_readb(info, AXP20X_FG_RES);
338 	if (fg_res < 0) {
339 		dev_err(&info->pdev->dev, "FG RES read failed: %d\n", fg_res);
340 		return;
341 	}
342 	if (!(fg_res & FG_REP_CAP_VALID))
343 		goto not_full;
344 
345 	fg_res &= ~FG_REP_CAP_VALID;
346 	if (fg_res == 100) {
347 		info->status = POWER_SUPPLY_STATUS_FULL;
348 		return;
349 	}
350 
351 	/*
352 	 * Sometimes the charger turns itself off before fg-res reaches 100%.
353 	 * When this happens the AXP288 reports a not-charging status and
354 	 * 0 mA discharge current.
355 	 */
356 	if (fg_res < 90 || (pwr_stat & PS_STAT_BAT_CHRG_DIR))
357 		goto not_full;
358 
359 	ret = iio_read_channel_raw(info->iio_channel[BAT_D_CURR], &curr);
360 	if (ret < 0) {
361 		dev_err(&info->pdev->dev, "FG get current failed: %d\n", ret);
362 		return;
363 	}
364 	if (curr == 0) {
365 		info->status = POWER_SUPPLY_STATUS_FULL;
366 		return;
367 	}
368 
369 not_full:
370 	if (pwr_stat & PS_STAT_BAT_CHRG_DIR)
371 		info->status = POWER_SUPPLY_STATUS_CHARGING;
372 	else
373 		info->status = POWER_SUPPLY_STATUS_DISCHARGING;
374 }
375 
376 static int fuel_gauge_get_vbatt(struct axp288_fg_info *info, int *vbatt)
377 {
378 	int ret = 0, raw_val;
379 
380 	ret = iio_read_channel_raw(info->iio_channel[BAT_VOLT], &raw_val);
381 	if (ret < 0)
382 		goto vbatt_read_fail;
383 
384 	*vbatt = VOLTAGE_FROM_ADC(raw_val);
385 vbatt_read_fail:
386 	return ret;
387 }
388 
389 static int fuel_gauge_get_current(struct axp288_fg_info *info, int *cur)
390 {
391 	int ret, discharge;
392 
393 	/* First check discharge current, so that we do only 1 read on bat. */
394 	ret = iio_read_channel_raw(info->iio_channel[BAT_D_CURR], &discharge);
395 	if (ret < 0)
396 		return ret;
397 
398 	if (discharge > 0) {
399 		*cur = -1 * discharge;
400 		return 0;
401 	}
402 
403 	return iio_read_channel_raw(info->iio_channel[BAT_CHRG_CURR], cur);
404 }
405 
406 static int fuel_gauge_get_vocv(struct axp288_fg_info *info, int *vocv)
407 {
408 	int ret;
409 
410 	ret = fuel_gauge_read_12bit_word(info, AXP288_FG_OCVH_REG);
411 	if (ret >= 0)
412 		*vocv = VOLTAGE_FROM_ADC(ret);
413 
414 	return ret;
415 }
416 
417 static int fuel_gauge_battery_health(struct axp288_fg_info *info)
418 {
419 	int ret, vocv, health = POWER_SUPPLY_HEALTH_UNKNOWN;
420 
421 	ret = fuel_gauge_get_vocv(info, &vocv);
422 	if (ret < 0)
423 		goto health_read_fail;
424 
425 	if (vocv > info->max_volt)
426 		health = POWER_SUPPLY_HEALTH_OVERVOLTAGE;
427 	else
428 		health = POWER_SUPPLY_HEALTH_GOOD;
429 
430 health_read_fail:
431 	return health;
432 }
433 
434 static int fuel_gauge_get_property(struct power_supply *ps,
435 		enum power_supply_property prop,
436 		union power_supply_propval *val)
437 {
438 	struct axp288_fg_info *info = power_supply_get_drvdata(ps);
439 	int ret = 0, value;
440 
441 	mutex_lock(&info->lock);
442 	switch (prop) {
443 	case POWER_SUPPLY_PROP_STATUS:
444 		fuel_gauge_get_status(info);
445 		val->intval = info->status;
446 		break;
447 	case POWER_SUPPLY_PROP_HEALTH:
448 		val->intval = fuel_gauge_battery_health(info);
449 		break;
450 	case POWER_SUPPLY_PROP_VOLTAGE_NOW:
451 		ret = fuel_gauge_get_vbatt(info, &value);
452 		if (ret < 0)
453 			goto fuel_gauge_read_err;
454 		val->intval = PROP_VOLT(value);
455 		break;
456 	case POWER_SUPPLY_PROP_VOLTAGE_OCV:
457 		ret = fuel_gauge_get_vocv(info, &value);
458 		if (ret < 0)
459 			goto fuel_gauge_read_err;
460 		val->intval = PROP_VOLT(value);
461 		break;
462 	case POWER_SUPPLY_PROP_CURRENT_NOW:
463 		ret = fuel_gauge_get_current(info, &value);
464 		if (ret < 0)
465 			goto fuel_gauge_read_err;
466 		val->intval = PROP_CURR(value);
467 		break;
468 	case POWER_SUPPLY_PROP_PRESENT:
469 		ret = fuel_gauge_reg_readb(info, AXP20X_PWR_OP_MODE);
470 		if (ret < 0)
471 			goto fuel_gauge_read_err;
472 
473 		if (ret & CHRG_STAT_BAT_PRESENT)
474 			val->intval = 1;
475 		else
476 			val->intval = 0;
477 		break;
478 	case POWER_SUPPLY_PROP_CAPACITY:
479 		ret = fuel_gauge_reg_readb(info, AXP20X_FG_RES);
480 		if (ret < 0)
481 			goto fuel_gauge_read_err;
482 
483 		if (!(ret & FG_REP_CAP_VALID))
484 			dev_err(&info->pdev->dev,
485 				"capacity measurement not valid\n");
486 		val->intval = (ret & FG_REP_CAP_VAL_MASK);
487 		break;
488 	case POWER_SUPPLY_PROP_CAPACITY_ALERT_MIN:
489 		ret = fuel_gauge_reg_readb(info, AXP288_FG_LOW_CAP_REG);
490 		if (ret < 0)
491 			goto fuel_gauge_read_err;
492 		val->intval = (ret & 0x0f);
493 		break;
494 	case POWER_SUPPLY_PROP_TECHNOLOGY:
495 		val->intval = POWER_SUPPLY_TECHNOLOGY_LION;
496 		break;
497 	case POWER_SUPPLY_PROP_CHARGE_NOW:
498 		ret = fuel_gauge_read_15bit_word(info, AXP288_FG_CC_MTR1_REG);
499 		if (ret < 0)
500 			goto fuel_gauge_read_err;
501 
502 		val->intval = ret * FG_DES_CAP_RES_LSB;
503 		break;
504 	case POWER_SUPPLY_PROP_CHARGE_FULL:
505 		ret = fuel_gauge_read_15bit_word(info, AXP288_FG_DES_CAP1_REG);
506 		if (ret < 0)
507 			goto fuel_gauge_read_err;
508 
509 		val->intval = ret * FG_DES_CAP_RES_LSB;
510 		break;
511 	case POWER_SUPPLY_PROP_VOLTAGE_MAX_DESIGN:
512 		val->intval = PROP_VOLT(info->max_volt);
513 		break;
514 	default:
515 		mutex_unlock(&info->lock);
516 		return -EINVAL;
517 	}
518 
519 	mutex_unlock(&info->lock);
520 	return 0;
521 
522 fuel_gauge_read_err:
523 	mutex_unlock(&info->lock);
524 	return ret;
525 }
526 
527 static int fuel_gauge_set_property(struct power_supply *ps,
528 		enum power_supply_property prop,
529 		const union power_supply_propval *val)
530 {
531 	struct axp288_fg_info *info = power_supply_get_drvdata(ps);
532 	int ret = 0;
533 
534 	mutex_lock(&info->lock);
535 	switch (prop) {
536 	case POWER_SUPPLY_PROP_CAPACITY_ALERT_MIN:
537 		if ((val->intval < 0) || (val->intval > 15)) {
538 			ret = -EINVAL;
539 			break;
540 		}
541 		ret = fuel_gauge_reg_readb(info, AXP288_FG_LOW_CAP_REG);
542 		if (ret < 0)
543 			break;
544 		ret &= 0xf0;
545 		ret |= (val->intval & 0xf);
546 		ret = fuel_gauge_reg_writeb(info, AXP288_FG_LOW_CAP_REG, ret);
547 		break;
548 	default:
549 		ret = -EINVAL;
550 		break;
551 	}
552 
553 	mutex_unlock(&info->lock);
554 	return ret;
555 }
556 
557 static int fuel_gauge_property_is_writeable(struct power_supply *psy,
558 	enum power_supply_property psp)
559 {
560 	int ret;
561 
562 	switch (psp) {
563 	case POWER_SUPPLY_PROP_CAPACITY_ALERT_MIN:
564 		ret = 1;
565 		break;
566 	default:
567 		ret = 0;
568 	}
569 
570 	return ret;
571 }
572 
573 static irqreturn_t fuel_gauge_thread_handler(int irq, void *dev)
574 {
575 	struct axp288_fg_info *info = dev;
576 	int i;
577 
578 	for (i = 0; i < AXP288_FG_INTR_NUM; i++) {
579 		if (info->irq[i] == irq)
580 			break;
581 	}
582 
583 	if (i >= AXP288_FG_INTR_NUM) {
584 		dev_warn(&info->pdev->dev, "spurious interrupt!!\n");
585 		return IRQ_NONE;
586 	}
587 
588 	switch (i) {
589 	case QWBTU_IRQ:
590 		dev_info(&info->pdev->dev,
591 			"Quit Battery under temperature in work mode IRQ (QWBTU)\n");
592 		break;
593 	case WBTU_IRQ:
594 		dev_info(&info->pdev->dev,
595 			"Battery under temperature in work mode IRQ (WBTU)\n");
596 		break;
597 	case QWBTO_IRQ:
598 		dev_info(&info->pdev->dev,
599 			"Quit Battery over temperature in work mode IRQ (QWBTO)\n");
600 		break;
601 	case WBTO_IRQ:
602 		dev_info(&info->pdev->dev,
603 			"Battery over temperature in work mode IRQ (WBTO)\n");
604 		break;
605 	case WL2_IRQ:
606 		dev_info(&info->pdev->dev, "Low Batt Warning(2) INTR\n");
607 		break;
608 	case WL1_IRQ:
609 		dev_info(&info->pdev->dev, "Low Batt Warning(1) INTR\n");
610 		break;
611 	default:
612 		dev_warn(&info->pdev->dev, "Spurious Interrupt!!!\n");
613 	}
614 
615 	power_supply_changed(info->bat);
616 	return IRQ_HANDLED;
617 }
618 
619 static void fuel_gauge_external_power_changed(struct power_supply *psy)
620 {
621 	struct axp288_fg_info *info = power_supply_get_drvdata(psy);
622 
623 	power_supply_changed(info->bat);
624 }
625 
626 static const struct power_supply_desc fuel_gauge_desc = {
627 	.name			= DEV_NAME,
628 	.type			= POWER_SUPPLY_TYPE_BATTERY,
629 	.properties		= fuel_gauge_props,
630 	.num_properties		= ARRAY_SIZE(fuel_gauge_props),
631 	.get_property		= fuel_gauge_get_property,
632 	.set_property		= fuel_gauge_set_property,
633 	.property_is_writeable	= fuel_gauge_property_is_writeable,
634 	.external_power_changed	= fuel_gauge_external_power_changed,
635 };
636 
637 static void fuel_gauge_init_irq(struct axp288_fg_info *info)
638 {
639 	int ret, i, pirq;
640 
641 	for (i = 0; i < AXP288_FG_INTR_NUM; i++) {
642 		pirq = platform_get_irq(info->pdev, i);
643 		info->irq[i] = regmap_irq_get_virq(info->regmap_irqc, pirq);
644 		if (info->irq[i] < 0) {
645 			dev_warn(&info->pdev->dev,
646 				"regmap_irq get virq failed for IRQ %d: %d\n",
647 				pirq, info->irq[i]);
648 			info->irq[i] = -1;
649 			goto intr_failed;
650 		}
651 		ret = request_threaded_irq(info->irq[i],
652 				NULL, fuel_gauge_thread_handler,
653 				IRQF_ONESHOT, DEV_NAME, info);
654 		if (ret) {
655 			dev_warn(&info->pdev->dev,
656 				"request irq failed for IRQ %d: %d\n",
657 				pirq, info->irq[i]);
658 			info->irq[i] = -1;
659 			goto intr_failed;
660 		} else {
661 			dev_info(&info->pdev->dev, "HW IRQ %d -> VIRQ %d\n",
662 				pirq, info->irq[i]);
663 		}
664 	}
665 	return;
666 
667 intr_failed:
668 	for (; i > 0; i--) {
669 		free_irq(info->irq[i - 1], info);
670 		info->irq[i - 1] = -1;
671 	}
672 }
673 
674 /*
675  * Some devices have no battery (HDMI sticks) and the axp288 battery's
676  * detection reports one despite it not being there.
677  * Please keep this listed sorted alphabetically.
678  */
679 static const struct dmi_system_id axp288_fuel_gauge_blacklist[] = {
680 	{
681 		/* ACEPC T8 Cherry Trail Z8350 mini PC */
682 		.matches = {
683 			DMI_EXACT_MATCH(DMI_BOARD_VENDOR, "To be filled by O.E.M."),
684 			DMI_EXACT_MATCH(DMI_BOARD_NAME, "Cherry Trail CR"),
685 			DMI_EXACT_MATCH(DMI_PRODUCT_SKU, "T8"),
686 			/* also match on somewhat unique bios-version */
687 			DMI_EXACT_MATCH(DMI_BIOS_VERSION, "1.000"),
688 		},
689 	},
690 	{
691 		/* ACEPC T11 Cherry Trail Z8350 mini PC */
692 		.matches = {
693 			DMI_EXACT_MATCH(DMI_BOARD_VENDOR, "To be filled by O.E.M."),
694 			DMI_EXACT_MATCH(DMI_BOARD_NAME, "Cherry Trail CR"),
695 			DMI_EXACT_MATCH(DMI_PRODUCT_SKU, "T11"),
696 			/* also match on somewhat unique bios-version */
697 			DMI_EXACT_MATCH(DMI_BIOS_VERSION, "1.000"),
698 		},
699 	},
700 	{
701 		/* ECS EF20EA */
702 		.matches = {
703 			DMI_MATCH(DMI_PRODUCT_NAME, "EF20EA"),
704 		},
705 	},
706 	{
707 		/* Intel Cherry Trail Compute Stick, Windows version */
708 		.matches = {
709 			DMI_MATCH(DMI_SYS_VENDOR, "Intel Corporation"),
710 			DMI_MATCH(DMI_PRODUCT_NAME, "STK1AW32SC"),
711 		},
712 	},
713 	{
714 		/* Intel Cherry Trail Compute Stick, version without an OS */
715 		.matches = {
716 			DMI_MATCH(DMI_SYS_VENDOR, "Intel Corporation"),
717 			DMI_MATCH(DMI_PRODUCT_NAME, "STK1A32SC"),
718 		},
719 	},
720 	{
721 		/* Meegopad T08 */
722 		.matches = {
723 			DMI_MATCH(DMI_SYS_VENDOR, "Default string"),
724 			DMI_MATCH(DMI_BOARD_VENDOR, "To be filled by OEM."),
725 			DMI_MATCH(DMI_BOARD_NAME, "T3 MRD"),
726 			DMI_MATCH(DMI_BOARD_VERSION, "V1.1"),
727 		},
728 	},
729 	{
730 		/* Minix Neo Z83-4 mini PC */
731 		.matches = {
732 			DMI_MATCH(DMI_SYS_VENDOR, "MINIX"),
733 			DMI_MATCH(DMI_PRODUCT_NAME, "Z83-4"),
734 		}
735 	},
736 	{}
737 };
738 
739 static int axp288_fuel_gauge_probe(struct platform_device *pdev)
740 {
741 	int i, ret = 0;
742 	struct axp288_fg_info *info;
743 	struct axp20x_dev *axp20x = dev_get_drvdata(pdev->dev.parent);
744 	struct power_supply_config psy_cfg = {};
745 	static const char * const iio_chan_name[] = {
746 		[BAT_TEMP] = "axp288-batt-temp",
747 		[PMIC_TEMP] = "axp288-pmic-temp",
748 		[SYSTEM_TEMP] = "axp288-system-temp",
749 		[BAT_CHRG_CURR] = "axp288-chrg-curr",
750 		[BAT_D_CURR] = "axp288-chrg-d-curr",
751 		[BAT_VOLT] = "axp288-batt-volt",
752 	};
753 	unsigned int val;
754 
755 	if (dmi_check_system(axp288_fuel_gauge_blacklist))
756 		return -ENODEV;
757 
758 	/*
759 	 * On some devices the fuelgauge and charger parts of the axp288 are
760 	 * not used, check that the fuelgauge is enabled (CC_CTRL != 0).
761 	 */
762 	ret = regmap_read(axp20x->regmap, AXP20X_CC_CTRL, &val);
763 	if (ret < 0)
764 		return ret;
765 	if (val == 0)
766 		return -ENODEV;
767 
768 	info = devm_kzalloc(&pdev->dev, sizeof(*info), GFP_KERNEL);
769 	if (!info)
770 		return -ENOMEM;
771 
772 	info->pdev = pdev;
773 	info->regmap = axp20x->regmap;
774 	info->regmap_irqc = axp20x->regmap_irqc;
775 	info->status = POWER_SUPPLY_STATUS_UNKNOWN;
776 
777 	platform_set_drvdata(pdev, info);
778 
779 	mutex_init(&info->lock);
780 
781 	for (i = 0; i < IIO_CHANNEL_NUM; i++) {
782 		/*
783 		 * Note cannot use devm_iio_channel_get because x86 systems
784 		 * lack the device<->channel maps which iio_channel_get will
785 		 * try to use when passed a non NULL device pointer.
786 		 */
787 		info->iio_channel[i] =
788 			iio_channel_get(NULL, iio_chan_name[i]);
789 		if (IS_ERR(info->iio_channel[i])) {
790 			ret = PTR_ERR(info->iio_channel[i]);
791 			dev_dbg(&pdev->dev, "error getting iiochan %s: %d\n",
792 				iio_chan_name[i], ret);
793 			/* Wait for axp288_adc to load */
794 			if (ret == -ENODEV)
795 				ret = -EPROBE_DEFER;
796 
797 			goto out_free_iio_chan;
798 		}
799 	}
800 
801 	ret = fuel_gauge_reg_readb(info, AXP288_FG_DES_CAP1_REG);
802 	if (ret < 0)
803 		goto out_free_iio_chan;
804 
805 	if (!(ret & FG_DES_CAP1_VALID)) {
806 		dev_err(&pdev->dev, "axp288 not configured by firmware\n");
807 		ret = -ENODEV;
808 		goto out_free_iio_chan;
809 	}
810 
811 	ret = fuel_gauge_reg_readb(info, AXP20X_CHRG_CTRL1);
812 	if (ret < 0)
813 		goto out_free_iio_chan;
814 	switch ((ret & CHRG_CCCV_CV_MASK) >> CHRG_CCCV_CV_BIT_POS) {
815 	case CHRG_CCCV_CV_4100MV:
816 		info->max_volt = 4100;
817 		break;
818 	case CHRG_CCCV_CV_4150MV:
819 		info->max_volt = 4150;
820 		break;
821 	case CHRG_CCCV_CV_4200MV:
822 		info->max_volt = 4200;
823 		break;
824 	case CHRG_CCCV_CV_4350MV:
825 		info->max_volt = 4350;
826 		break;
827 	}
828 
829 	psy_cfg.drv_data = info;
830 	info->bat = power_supply_register(&pdev->dev, &fuel_gauge_desc, &psy_cfg);
831 	if (IS_ERR(info->bat)) {
832 		ret = PTR_ERR(info->bat);
833 		dev_err(&pdev->dev, "failed to register battery: %d\n", ret);
834 		goto out_free_iio_chan;
835 	}
836 
837 	fuel_gauge_create_debugfs(info);
838 	fuel_gauge_init_irq(info);
839 
840 	return 0;
841 
842 out_free_iio_chan:
843 	for (i = 0; i < IIO_CHANNEL_NUM; i++)
844 		if (!IS_ERR_OR_NULL(info->iio_channel[i]))
845 			iio_channel_release(info->iio_channel[i]);
846 
847 	return ret;
848 }
849 
850 static const struct platform_device_id axp288_fg_id_table[] = {
851 	{ .name = DEV_NAME },
852 	{},
853 };
854 MODULE_DEVICE_TABLE(platform, axp288_fg_id_table);
855 
856 static int axp288_fuel_gauge_remove(struct platform_device *pdev)
857 {
858 	struct axp288_fg_info *info = platform_get_drvdata(pdev);
859 	int i;
860 
861 	power_supply_unregister(info->bat);
862 	fuel_gauge_remove_debugfs(info);
863 
864 	for (i = 0; i < AXP288_FG_INTR_NUM; i++)
865 		if (info->irq[i] >= 0)
866 			free_irq(info->irq[i], info);
867 
868 	for (i = 0; i < IIO_CHANNEL_NUM; i++)
869 		iio_channel_release(info->iio_channel[i]);
870 
871 	return 0;
872 }
873 
874 static struct platform_driver axp288_fuel_gauge_driver = {
875 	.probe = axp288_fuel_gauge_probe,
876 	.remove = axp288_fuel_gauge_remove,
877 	.id_table = axp288_fg_id_table,
878 	.driver = {
879 		.name = DEV_NAME,
880 	},
881 };
882 
883 module_platform_driver(axp288_fuel_gauge_driver);
884 
885 MODULE_AUTHOR("Ramakrishna Pallala <ramakrishna.pallala@intel.com>");
886 MODULE_AUTHOR("Todd Brandt <todd.e.brandt@linux.intel.com>");
887 MODULE_DESCRIPTION("Xpower AXP288 Fuel Gauge Driver");
888 MODULE_LICENSE("GPL");
889