1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * Copyright (C) ST-Ericsson SA 2012
4  *
5  * Battery temperature driver for AB8500
6  *
7  * Author:
8  *	Johan Palsson <johan.palsson@stericsson.com>
9  *	Karl Komierowski <karl.komierowski@stericsson.com>
10  *	Arun R Murthy <arun.murthy@stericsson.com>
11  */
12 
13 #include <linux/init.h>
14 #include <linux/module.h>
15 #include <linux/device.h>
16 #include <linux/interrupt.h>
17 #include <linux/delay.h>
18 #include <linux/slab.h>
19 #include <linux/platform_device.h>
20 #include <linux/power_supply.h>
21 #include <linux/completion.h>
22 #include <linux/workqueue.h>
23 #include <linux/jiffies.h>
24 #include <linux/of.h>
25 #include <linux/mfd/core.h>
26 #include <linux/mfd/abx500.h>
27 #include <linux/mfd/abx500/ab8500.h>
28 #include <linux/mfd/abx500/ab8500-bm.h>
29 #include <linux/iio/consumer.h>
30 
31 #define VTVOUT_V			1800
32 
33 #define BTEMP_THERMAL_LOW_LIMIT		-10
34 #define BTEMP_THERMAL_MED_LIMIT		0
35 #define BTEMP_THERMAL_HIGH_LIMIT_52	52
36 #define BTEMP_THERMAL_HIGH_LIMIT_57	57
37 #define BTEMP_THERMAL_HIGH_LIMIT_62	62
38 
39 #define BTEMP_BATCTRL_CURR_SRC_7UA	7
40 #define BTEMP_BATCTRL_CURR_SRC_20UA	20
41 
42 #define BTEMP_BATCTRL_CURR_SRC_16UA	16
43 #define BTEMP_BATCTRL_CURR_SRC_18UA	18
44 
45 #define BTEMP_BATCTRL_CURR_SRC_60UA	60
46 #define BTEMP_BATCTRL_CURR_SRC_120UA	120
47 
48 /**
49  * struct ab8500_btemp_interrupts - ab8500 interrupts
50  * @name:	name of the interrupt
51  * @isr		function pointer to the isr
52  */
53 struct ab8500_btemp_interrupts {
54 	char *name;
55 	irqreturn_t (*isr)(int irq, void *data);
56 };
57 
58 struct ab8500_btemp_events {
59 	bool batt_rem;
60 	bool btemp_high;
61 	bool btemp_medhigh;
62 	bool btemp_lowmed;
63 	bool btemp_low;
64 	bool ac_conn;
65 	bool usb_conn;
66 };
67 
68 struct ab8500_btemp_ranges {
69 	int btemp_high_limit;
70 	int btemp_med_limit;
71 	int btemp_low_limit;
72 };
73 
74 /**
75  * struct ab8500_btemp - ab8500 BTEMP device information
76  * @dev:		Pointer to the structure device
77  * @node:		List of AB8500 BTEMPs, hence prepared for reentrance
78  * @curr_source:	What current source we use, in uA
79  * @bat_temp:		Dispatched battery temperature in degree Celsius
80  * @prev_bat_temp	Last measured battery temperature in degree Celsius
81  * @parent:		Pointer to the struct ab8500
82  * @adc_btemp_ball:	ADC channel for the battery ball temperature
83  * @adc_bat_ctrl:	ADC channel for the battery control
84  * @fg:			Pointer to the struct fg
85  * @bm:           	Platform specific battery management information
86  * @btemp_psy:		Structure for BTEMP specific battery properties
87  * @events:		Structure for information about events triggered
88  * @btemp_ranges:	Battery temperature range structure
89  * @btemp_wq:		Work queue for measuring the temperature periodically
90  * @btemp_periodic_work:	Work for measuring the temperature periodically
91  * @initialized:	True if battery id read.
92  */
93 struct ab8500_btemp {
94 	struct device *dev;
95 	struct list_head node;
96 	int curr_source;
97 	int bat_temp;
98 	int prev_bat_temp;
99 	struct ab8500 *parent;
100 	struct iio_channel *btemp_ball;
101 	struct iio_channel *bat_ctrl;
102 	struct ab8500_fg *fg;
103 	struct abx500_bm_data *bm;
104 	struct power_supply *btemp_psy;
105 	struct ab8500_btemp_events events;
106 	struct ab8500_btemp_ranges btemp_ranges;
107 	struct workqueue_struct *btemp_wq;
108 	struct delayed_work btemp_periodic_work;
109 	bool initialized;
110 };
111 
112 /* BTEMP power supply properties */
113 static enum power_supply_property ab8500_btemp_props[] = {
114 	POWER_SUPPLY_PROP_PRESENT,
115 	POWER_SUPPLY_PROP_ONLINE,
116 	POWER_SUPPLY_PROP_TECHNOLOGY,
117 	POWER_SUPPLY_PROP_TEMP,
118 };
119 
120 static LIST_HEAD(ab8500_btemp_list);
121 
122 /**
123  * ab8500_btemp_get() - returns a reference to the primary AB8500 BTEMP
124  * (i.e. the first BTEMP in the instance list)
125  */
126 struct ab8500_btemp *ab8500_btemp_get(void)
127 {
128 	return list_first_entry(&ab8500_btemp_list, struct ab8500_btemp, node);
129 }
130 EXPORT_SYMBOL(ab8500_btemp_get);
131 
132 /**
133  * ab8500_btemp_batctrl_volt_to_res() - convert batctrl voltage to resistance
134  * @di:		pointer to the ab8500_btemp structure
135  * @v_batctrl:	measured batctrl voltage
136  * @inst_curr:	measured instant current
137  *
138  * This function returns the battery resistance that is
139  * derived from the BATCTRL voltage.
140  * Returns value in Ohms.
141  */
142 static int ab8500_btemp_batctrl_volt_to_res(struct ab8500_btemp *di,
143 	int v_batctrl, int inst_curr)
144 {
145 	int rbs;
146 
147 	if (is_ab8500_1p1_or_earlier(di->parent)) {
148 		/*
149 		 * For ABB cut1.0 and 1.1 BAT_CTRL is internally
150 		 * connected to 1.8V through a 450k resistor
151 		 */
152 		return (450000 * (v_batctrl)) / (1800 - v_batctrl);
153 	}
154 
155 	if (di->bm->adc_therm == ABx500_ADC_THERM_BATCTRL) {
156 		/*
157 		 * If the battery has internal NTC, we use the current
158 		 * source to calculate the resistance.
159 		 */
160 		rbs = (v_batctrl * 1000
161 		       - di->bm->gnd_lift_resistance * inst_curr)
162 		      / di->curr_source;
163 	} else {
164 		/*
165 		 * BAT_CTRL is internally
166 		 * connected to 1.8V through a 80k resistor
167 		 */
168 		rbs = (80000 * (v_batctrl)) / (1800 - v_batctrl);
169 	}
170 
171 	return rbs;
172 }
173 
174 /**
175  * ab8500_btemp_read_batctrl_voltage() - measure batctrl voltage
176  * @di:		pointer to the ab8500_btemp structure
177  *
178  * This function returns the voltage on BATCTRL. Returns value in mV.
179  */
180 static int ab8500_btemp_read_batctrl_voltage(struct ab8500_btemp *di)
181 {
182 	int vbtemp, ret;
183 	static int prev;
184 
185 	ret = iio_read_channel_processed(di->bat_ctrl, &vbtemp);
186 	if (ret < 0) {
187 		dev_err(di->dev,
188 			"%s ADC conversion failed, using previous value",
189 			__func__);
190 		return prev;
191 	}
192 	prev = vbtemp;
193 	return vbtemp;
194 }
195 
196 /**
197  * ab8500_btemp_curr_source_enable() - enable/disable batctrl current source
198  * @di:		pointer to the ab8500_btemp structure
199  * @enable:	enable or disable the current source
200  *
201  * Enable or disable the current sources for the BatCtrl AD channel
202  */
203 static int ab8500_btemp_curr_source_enable(struct ab8500_btemp *di,
204 	bool enable)
205 {
206 	int curr;
207 	int ret = 0;
208 
209 	/*
210 	 * BATCTRL current sources are included on AB8500 cut2.0
211 	 * and future versions
212 	 */
213 	if (is_ab8500_1p1_or_earlier(di->parent))
214 		return 0;
215 
216 	/* Only do this for batteries with internal NTC */
217 	if (di->bm->adc_therm == ABx500_ADC_THERM_BATCTRL && enable) {
218 
219 		if (di->curr_source == BTEMP_BATCTRL_CURR_SRC_7UA)
220 			curr = BAT_CTRL_7U_ENA;
221 		else
222 			curr = BAT_CTRL_20U_ENA;
223 
224 		dev_dbg(di->dev, "Set BATCTRL %duA\n", di->curr_source);
225 
226 		ret = abx500_mask_and_set_register_interruptible(di->dev,
227 			AB8500_CHARGER, AB8500_BAT_CTRL_CURRENT_SOURCE,
228 			FORCE_BAT_CTRL_CMP_HIGH, FORCE_BAT_CTRL_CMP_HIGH);
229 		if (ret) {
230 			dev_err(di->dev, "%s failed setting cmp_force\n",
231 				__func__);
232 			return ret;
233 		}
234 
235 		/*
236 		 * We have to wait one 32kHz cycle before enabling
237 		 * the current source, since ForceBatCtrlCmpHigh needs
238 		 * to be written in a separate cycle
239 		 */
240 		udelay(32);
241 
242 		ret = abx500_set_register_interruptible(di->dev,
243 			AB8500_CHARGER, AB8500_BAT_CTRL_CURRENT_SOURCE,
244 			FORCE_BAT_CTRL_CMP_HIGH | curr);
245 		if (ret) {
246 			dev_err(di->dev, "%s failed enabling current source\n",
247 				__func__);
248 			goto disable_curr_source;
249 		}
250 	} else if (di->bm->adc_therm == ABx500_ADC_THERM_BATCTRL && !enable) {
251 		dev_dbg(di->dev, "Disable BATCTRL curr source\n");
252 
253 		/* Write 0 to the curr bits */
254 		ret = abx500_mask_and_set_register_interruptible(
255 			di->dev,
256 			AB8500_CHARGER, AB8500_BAT_CTRL_CURRENT_SOURCE,
257 			BAT_CTRL_7U_ENA | BAT_CTRL_20U_ENA,
258 			~(BAT_CTRL_7U_ENA | BAT_CTRL_20U_ENA));
259 
260 		if (ret) {
261 			dev_err(di->dev, "%s failed disabling current source\n",
262 				__func__);
263 			goto disable_curr_source;
264 		}
265 
266 		/* Enable Pull-Up and comparator */
267 		ret = abx500_mask_and_set_register_interruptible(di->dev,
268 			AB8500_CHARGER,	AB8500_BAT_CTRL_CURRENT_SOURCE,
269 			BAT_CTRL_PULL_UP_ENA | BAT_CTRL_CMP_ENA,
270 			BAT_CTRL_PULL_UP_ENA | BAT_CTRL_CMP_ENA);
271 		if (ret) {
272 			dev_err(di->dev, "%s failed enabling PU and comp\n",
273 				__func__);
274 			goto enable_pu_comp;
275 		}
276 
277 		/*
278 		 * We have to wait one 32kHz cycle before disabling
279 		 * ForceBatCtrlCmpHigh since this needs to be written
280 		 * in a separate cycle
281 		 */
282 		udelay(32);
283 
284 		/* Disable 'force comparator' */
285 		ret = abx500_mask_and_set_register_interruptible(di->dev,
286 			AB8500_CHARGER, AB8500_BAT_CTRL_CURRENT_SOURCE,
287 			FORCE_BAT_CTRL_CMP_HIGH, ~FORCE_BAT_CTRL_CMP_HIGH);
288 		if (ret) {
289 			dev_err(di->dev, "%s failed disabling force comp\n",
290 				__func__);
291 			goto disable_force_comp;
292 		}
293 	}
294 	return ret;
295 
296 	/*
297 	 * We have to try unsetting FORCE_BAT_CTRL_CMP_HIGH one more time
298 	 * if we got an error above
299 	 */
300 disable_curr_source:
301 	/* Write 0 to the curr bits */
302 	ret = abx500_mask_and_set_register_interruptible(di->dev,
303 		AB8500_CHARGER, AB8500_BAT_CTRL_CURRENT_SOURCE,
304 		BAT_CTRL_7U_ENA | BAT_CTRL_20U_ENA,
305 		~(BAT_CTRL_7U_ENA | BAT_CTRL_20U_ENA));
306 
307 	if (ret) {
308 		dev_err(di->dev, "%s failed disabling current source\n",
309 			__func__);
310 		return ret;
311 	}
312 enable_pu_comp:
313 	/* Enable Pull-Up and comparator */
314 	ret = abx500_mask_and_set_register_interruptible(di->dev,
315 		AB8500_CHARGER,	AB8500_BAT_CTRL_CURRENT_SOURCE,
316 		BAT_CTRL_PULL_UP_ENA | BAT_CTRL_CMP_ENA,
317 		BAT_CTRL_PULL_UP_ENA | BAT_CTRL_CMP_ENA);
318 	if (ret) {
319 		dev_err(di->dev, "%s failed enabling PU and comp\n",
320 			__func__);
321 		return ret;
322 	}
323 
324 disable_force_comp:
325 	/*
326 	 * We have to wait one 32kHz cycle before disabling
327 	 * ForceBatCtrlCmpHigh since this needs to be written
328 	 * in a separate cycle
329 	 */
330 	udelay(32);
331 
332 	/* Disable 'force comparator' */
333 	ret = abx500_mask_and_set_register_interruptible(di->dev,
334 		AB8500_CHARGER, AB8500_BAT_CTRL_CURRENT_SOURCE,
335 		FORCE_BAT_CTRL_CMP_HIGH, ~FORCE_BAT_CTRL_CMP_HIGH);
336 	if (ret) {
337 		dev_err(di->dev, "%s failed disabling force comp\n",
338 			__func__);
339 		return ret;
340 	}
341 
342 	return ret;
343 }
344 
345 /**
346  * ab8500_btemp_get_batctrl_res() - get battery resistance
347  * @di:		pointer to the ab8500_btemp structure
348  *
349  * This function returns the battery pack identification resistance.
350  * Returns value in Ohms.
351  */
352 static int ab8500_btemp_get_batctrl_res(struct ab8500_btemp *di)
353 {
354 	int ret;
355 	int batctrl = 0;
356 	int res;
357 	int inst_curr;
358 	int i;
359 
360 	/*
361 	 * BATCTRL current sources are included on AB8500 cut2.0
362 	 * and future versions
363 	 */
364 	ret = ab8500_btemp_curr_source_enable(di, true);
365 	if (ret) {
366 		dev_err(di->dev, "%s curr source enabled failed\n", __func__);
367 		return ret;
368 	}
369 
370 	if (!di->fg)
371 		di->fg = ab8500_fg_get();
372 	if (!di->fg) {
373 		dev_err(di->dev, "No fg found\n");
374 		return -EINVAL;
375 	}
376 
377 	ret = ab8500_fg_inst_curr_start(di->fg);
378 
379 	if (ret) {
380 		dev_err(di->dev, "Failed to start current measurement\n");
381 		return ret;
382 	}
383 
384 	do {
385 		msleep(20);
386 	} while (!ab8500_fg_inst_curr_started(di->fg));
387 
388 	i = 0;
389 
390 	do {
391 		batctrl += ab8500_btemp_read_batctrl_voltage(di);
392 		i++;
393 		msleep(20);
394 	} while (!ab8500_fg_inst_curr_done(di->fg));
395 	batctrl /= i;
396 
397 	ret = ab8500_fg_inst_curr_finalize(di->fg, &inst_curr);
398 	if (ret) {
399 		dev_err(di->dev, "Failed to finalize current measurement\n");
400 		return ret;
401 	}
402 
403 	res = ab8500_btemp_batctrl_volt_to_res(di, batctrl, inst_curr);
404 
405 	ret = ab8500_btemp_curr_source_enable(di, false);
406 	if (ret) {
407 		dev_err(di->dev, "%s curr source disable failed\n", __func__);
408 		return ret;
409 	}
410 
411 	dev_dbg(di->dev, "%s batctrl: %d res: %d inst_curr: %d samples: %d\n",
412 		__func__, batctrl, res, inst_curr, i);
413 
414 	return res;
415 }
416 
417 /**
418  * ab8500_btemp_res_to_temp() - resistance to temperature
419  * @di:		pointer to the ab8500_btemp structure
420  * @tbl:	pointer to the resiatance to temperature table
421  * @tbl_size:	size of the resistance to temperature table
422  * @res:	resistance to calculate the temperature from
423  *
424  * This function returns the battery temperature in degrees Celsius
425  * based on the NTC resistance.
426  */
427 static int ab8500_btemp_res_to_temp(struct ab8500_btemp *di,
428 	const struct abx500_res_to_temp *tbl, int tbl_size, int res)
429 {
430 	int i;
431 	/*
432 	 * Calculate the formula for the straight line
433 	 * Simple interpolation if we are within
434 	 * the resistance table limits, extrapolate
435 	 * if resistance is outside the limits.
436 	 */
437 	if (res > tbl[0].resist)
438 		i = 0;
439 	else if (res <= tbl[tbl_size - 1].resist)
440 		i = tbl_size - 2;
441 	else {
442 		i = 0;
443 		while (!(res <= tbl[i].resist &&
444 			res > tbl[i + 1].resist))
445 			i++;
446 	}
447 
448 	return tbl[i].temp + ((tbl[i + 1].temp - tbl[i].temp) *
449 		(res - tbl[i].resist)) / (tbl[i + 1].resist - tbl[i].resist);
450 }
451 
452 /**
453  * ab8500_btemp_measure_temp() - measure battery temperature
454  * @di:		pointer to the ab8500_btemp structure
455  *
456  * Returns battery temperature (on success) else the previous temperature
457  */
458 static int ab8500_btemp_measure_temp(struct ab8500_btemp *di)
459 {
460 	int temp, ret;
461 	static int prev;
462 	int rbat, rntc, vntc;
463 	u8 id;
464 
465 	id = di->bm->batt_id;
466 
467 	if (di->bm->adc_therm == ABx500_ADC_THERM_BATCTRL &&
468 			id != BATTERY_UNKNOWN) {
469 
470 		rbat = ab8500_btemp_get_batctrl_res(di);
471 		if (rbat < 0) {
472 			dev_err(di->dev, "%s get batctrl res failed\n",
473 				__func__);
474 			/*
475 			 * Return out-of-range temperature so that
476 			 * charging is stopped
477 			 */
478 			return BTEMP_THERMAL_LOW_LIMIT;
479 		}
480 
481 		temp = ab8500_btemp_res_to_temp(di,
482 			di->bm->bat_type[id].r_to_t_tbl,
483 			di->bm->bat_type[id].n_temp_tbl_elements, rbat);
484 	} else {
485 		ret = iio_read_channel_processed(di->btemp_ball, &vntc);
486 		if (ret < 0) {
487 			dev_err(di->dev,
488 				"%s ADC conversion failed,"
489 				" using previous value\n", __func__);
490 			return prev;
491 		}
492 		/*
493 		 * The PCB NTC is sourced from VTVOUT via a 230kOhm
494 		 * resistor.
495 		 */
496 		rntc = 230000 * vntc / (VTVOUT_V - vntc);
497 
498 		temp = ab8500_btemp_res_to_temp(di,
499 			di->bm->bat_type[id].r_to_t_tbl,
500 			di->bm->bat_type[id].n_temp_tbl_elements, rntc);
501 		prev = temp;
502 	}
503 	dev_dbg(di->dev, "Battery temperature is %d\n", temp);
504 	return temp;
505 }
506 
507 /**
508  * ab8500_btemp_id() - Identify the connected battery
509  * @di:		pointer to the ab8500_btemp structure
510  *
511  * This function will try to identify the battery by reading the ID
512  * resistor. Some brands use a combined ID resistor with a NTC resistor to
513  * both be able to identify and to read the temperature of it.
514  */
515 static int ab8500_btemp_id(struct ab8500_btemp *di)
516 {
517 	int res;
518 	u8 i;
519 
520 	di->curr_source = BTEMP_BATCTRL_CURR_SRC_7UA;
521 	di->bm->batt_id = BATTERY_UNKNOWN;
522 
523 	res =  ab8500_btemp_get_batctrl_res(di);
524 	if (res < 0) {
525 		dev_err(di->dev, "%s get batctrl res failed\n", __func__);
526 		return -ENXIO;
527 	}
528 
529 	/* BATTERY_UNKNOWN is defined on position 0, skip it! */
530 	for (i = BATTERY_UNKNOWN + 1; i < di->bm->n_btypes; i++) {
531 		if ((res <= di->bm->bat_type[i].resis_high) &&
532 			(res >= di->bm->bat_type[i].resis_low)) {
533 			dev_dbg(di->dev, "Battery detected on %s"
534 				" low %d < res %d < high: %d"
535 				" index: %d\n",
536 				di->bm->adc_therm == ABx500_ADC_THERM_BATCTRL ?
537 				"BATCTRL" : "BATTEMP",
538 				di->bm->bat_type[i].resis_low, res,
539 				di->bm->bat_type[i].resis_high, i);
540 
541 			di->bm->batt_id = i;
542 			break;
543 		}
544 	}
545 
546 	if (di->bm->batt_id == BATTERY_UNKNOWN) {
547 		dev_warn(di->dev, "Battery identified as unknown"
548 			", resistance %d Ohm\n", res);
549 		return -ENXIO;
550 	}
551 
552 	/*
553 	 * We only have to change current source if the
554 	 * detected type is Type 1.
555 	 */
556 	if (di->bm->adc_therm == ABx500_ADC_THERM_BATCTRL &&
557 	    di->bm->batt_id == 1) {
558 		dev_dbg(di->dev, "Set BATCTRL current source to 20uA\n");
559 		di->curr_source = BTEMP_BATCTRL_CURR_SRC_20UA;
560 	}
561 
562 	return di->bm->batt_id;
563 }
564 
565 /**
566  * ab8500_btemp_periodic_work() - Measuring the temperature periodically
567  * @work:	pointer to the work_struct structure
568  *
569  * Work function for measuring the temperature periodically
570  */
571 static void ab8500_btemp_periodic_work(struct work_struct *work)
572 {
573 	int interval;
574 	int bat_temp;
575 	struct ab8500_btemp *di = container_of(work,
576 		struct ab8500_btemp, btemp_periodic_work.work);
577 
578 	if (!di->initialized) {
579 		/* Identify the battery */
580 		if (ab8500_btemp_id(di) < 0)
581 			dev_warn(di->dev, "failed to identify the battery\n");
582 	}
583 
584 	bat_temp = ab8500_btemp_measure_temp(di);
585 	/*
586 	 * Filter battery temperature.
587 	 * Allow direct updates on temperature only if two samples result in
588 	 * same temperature. Else only allow 1 degree change from previous
589 	 * reported value in the direction of the new measurement.
590 	 */
591 	if ((bat_temp == di->prev_bat_temp) || !di->initialized) {
592 		if ((di->bat_temp != di->prev_bat_temp) || !di->initialized) {
593 			di->initialized = true;
594 			di->bat_temp = bat_temp;
595 			power_supply_changed(di->btemp_psy);
596 		}
597 	} else if (bat_temp < di->prev_bat_temp) {
598 		di->bat_temp--;
599 		power_supply_changed(di->btemp_psy);
600 	} else if (bat_temp > di->prev_bat_temp) {
601 		di->bat_temp++;
602 		power_supply_changed(di->btemp_psy);
603 	}
604 	di->prev_bat_temp = bat_temp;
605 
606 	if (di->events.ac_conn || di->events.usb_conn)
607 		interval = di->bm->temp_interval_chg;
608 	else
609 		interval = di->bm->temp_interval_nochg;
610 
611 	/* Schedule a new measurement */
612 	queue_delayed_work(di->btemp_wq,
613 		&di->btemp_periodic_work,
614 		round_jiffies(interval * HZ));
615 }
616 
617 /**
618  * ab8500_btemp_batctrlindb_handler() - battery removal detected
619  * @irq:       interrupt number
620  * @_di:       void pointer that has to address of ab8500_btemp
621  *
622  * Returns IRQ status(IRQ_HANDLED)
623  */
624 static irqreturn_t ab8500_btemp_batctrlindb_handler(int irq, void *_di)
625 {
626 	struct ab8500_btemp *di = _di;
627 	dev_err(di->dev, "Battery removal detected!\n");
628 
629 	di->events.batt_rem = true;
630 	power_supply_changed(di->btemp_psy);
631 
632 	return IRQ_HANDLED;
633 }
634 
635 /**
636  * ab8500_btemp_templow_handler() - battery temp lower than 10 degrees
637  * @irq:       interrupt number
638  * @_di:       void pointer that has to address of ab8500_btemp
639  *
640  * Returns IRQ status(IRQ_HANDLED)
641  */
642 static irqreturn_t ab8500_btemp_templow_handler(int irq, void *_di)
643 {
644 	struct ab8500_btemp *di = _di;
645 
646 	if (is_ab8500_3p3_or_earlier(di->parent)) {
647 		dev_dbg(di->dev, "Ignore false btemp low irq"
648 			" for ABB cut 1.0, 1.1, 2.0 and 3.3\n");
649 	} else {
650 		dev_crit(di->dev, "Battery temperature lower than -10deg c\n");
651 
652 		di->events.btemp_low = true;
653 		di->events.btemp_high = false;
654 		di->events.btemp_medhigh = false;
655 		di->events.btemp_lowmed = false;
656 		power_supply_changed(di->btemp_psy);
657 	}
658 
659 	return IRQ_HANDLED;
660 }
661 
662 /**
663  * ab8500_btemp_temphigh_handler() - battery temp higher than max temp
664  * @irq:       interrupt number
665  * @_di:       void pointer that has to address of ab8500_btemp
666  *
667  * Returns IRQ status(IRQ_HANDLED)
668  */
669 static irqreturn_t ab8500_btemp_temphigh_handler(int irq, void *_di)
670 {
671 	struct ab8500_btemp *di = _di;
672 
673 	dev_crit(di->dev, "Battery temperature is higher than MAX temp\n");
674 
675 	di->events.btemp_high = true;
676 	di->events.btemp_medhigh = false;
677 	di->events.btemp_lowmed = false;
678 	di->events.btemp_low = false;
679 	power_supply_changed(di->btemp_psy);
680 
681 	return IRQ_HANDLED;
682 }
683 
684 /**
685  * ab8500_btemp_lowmed_handler() - battery temp between low and medium
686  * @irq:       interrupt number
687  * @_di:       void pointer that has to address of ab8500_btemp
688  *
689  * Returns IRQ status(IRQ_HANDLED)
690  */
691 static irqreturn_t ab8500_btemp_lowmed_handler(int irq, void *_di)
692 {
693 	struct ab8500_btemp *di = _di;
694 
695 	dev_dbg(di->dev, "Battery temperature is between low and medium\n");
696 
697 	di->events.btemp_lowmed = true;
698 	di->events.btemp_medhigh = false;
699 	di->events.btemp_high = false;
700 	di->events.btemp_low = false;
701 	power_supply_changed(di->btemp_psy);
702 
703 	return IRQ_HANDLED;
704 }
705 
706 /**
707  * ab8500_btemp_medhigh_handler() - battery temp between medium and high
708  * @irq:       interrupt number
709  * @_di:       void pointer that has to address of ab8500_btemp
710  *
711  * Returns IRQ status(IRQ_HANDLED)
712  */
713 static irqreturn_t ab8500_btemp_medhigh_handler(int irq, void *_di)
714 {
715 	struct ab8500_btemp *di = _di;
716 
717 	dev_dbg(di->dev, "Battery temperature is between medium and high\n");
718 
719 	di->events.btemp_medhigh = true;
720 	di->events.btemp_lowmed = false;
721 	di->events.btemp_high = false;
722 	di->events.btemp_low = false;
723 	power_supply_changed(di->btemp_psy);
724 
725 	return IRQ_HANDLED;
726 }
727 
728 /**
729  * ab8500_btemp_periodic() - Periodic temperature measurements
730  * @di:		pointer to the ab8500_btemp structure
731  * @enable:	enable or disable periodic temperature measurements
732  *
733  * Starts of stops periodic temperature measurements. Periodic measurements
734  * should only be done when a charger is connected.
735  */
736 static void ab8500_btemp_periodic(struct ab8500_btemp *di,
737 	bool enable)
738 {
739 	dev_dbg(di->dev, "Enable periodic temperature measurements: %d\n",
740 		enable);
741 	/*
742 	 * Make sure a new measurement is done directly by cancelling
743 	 * any pending work
744 	 */
745 	cancel_delayed_work_sync(&di->btemp_periodic_work);
746 
747 	if (enable)
748 		queue_delayed_work(di->btemp_wq, &di->btemp_periodic_work, 0);
749 }
750 
751 /**
752  * ab8500_btemp_get_temp() - get battery temperature
753  * @di:		pointer to the ab8500_btemp structure
754  *
755  * Returns battery temperature
756  */
757 int ab8500_btemp_get_temp(struct ab8500_btemp *di)
758 {
759 	int temp = 0;
760 
761 	/*
762 	 * The BTEMP events are not reliabe on AB8500 cut3.3
763 	 * and prior versions
764 	 */
765 	if (is_ab8500_3p3_or_earlier(di->parent)) {
766 		temp = di->bat_temp * 10;
767 	} else {
768 		if (di->events.btemp_low) {
769 			if (temp > di->btemp_ranges.btemp_low_limit)
770 				temp = di->btemp_ranges.btemp_low_limit * 10;
771 			else
772 				temp = di->bat_temp * 10;
773 		} else if (di->events.btemp_high) {
774 			if (temp < di->btemp_ranges.btemp_high_limit)
775 				temp = di->btemp_ranges.btemp_high_limit * 10;
776 			else
777 				temp = di->bat_temp * 10;
778 		} else if (di->events.btemp_lowmed) {
779 			if (temp > di->btemp_ranges.btemp_med_limit)
780 				temp = di->btemp_ranges.btemp_med_limit * 10;
781 			else
782 				temp = di->bat_temp * 10;
783 		} else if (di->events.btemp_medhigh) {
784 			if (temp < di->btemp_ranges.btemp_med_limit)
785 				temp = di->btemp_ranges.btemp_med_limit * 10;
786 			else
787 				temp = di->bat_temp * 10;
788 		} else
789 			temp = di->bat_temp * 10;
790 	}
791 	return temp;
792 }
793 EXPORT_SYMBOL(ab8500_btemp_get_temp);
794 
795 /**
796  * ab8500_btemp_get_batctrl_temp() - get the temperature
797  * @btemp:      pointer to the btemp structure
798  *
799  * Returns the batctrl temperature in millidegrees
800  */
801 int ab8500_btemp_get_batctrl_temp(struct ab8500_btemp *btemp)
802 {
803 	return btemp->bat_temp * 1000;
804 }
805 EXPORT_SYMBOL(ab8500_btemp_get_batctrl_temp);
806 
807 /**
808  * ab8500_btemp_get_property() - get the btemp properties
809  * @psy:        pointer to the power_supply structure
810  * @psp:        pointer to the power_supply_property structure
811  * @val:        pointer to the power_supply_propval union
812  *
813  * This function gets called when an application tries to get the btemp
814  * properties by reading the sysfs files.
815  * online:	presence of the battery
816  * present:	presence of the battery
817  * technology:	battery technology
818  * temp:	battery temperature
819  * Returns error code in case of failure else 0(on success)
820  */
821 static int ab8500_btemp_get_property(struct power_supply *psy,
822 	enum power_supply_property psp,
823 	union power_supply_propval *val)
824 {
825 	struct ab8500_btemp *di = power_supply_get_drvdata(psy);
826 
827 	switch (psp) {
828 	case POWER_SUPPLY_PROP_PRESENT:
829 	case POWER_SUPPLY_PROP_ONLINE:
830 		if (di->events.batt_rem)
831 			val->intval = 0;
832 		else
833 			val->intval = 1;
834 		break;
835 	case POWER_SUPPLY_PROP_TECHNOLOGY:
836 		val->intval = di->bm->bat_type[di->bm->batt_id].name;
837 		break;
838 	case POWER_SUPPLY_PROP_TEMP:
839 		val->intval = ab8500_btemp_get_temp(di);
840 		break;
841 	default:
842 		return -EINVAL;
843 	}
844 	return 0;
845 }
846 
847 static int ab8500_btemp_get_ext_psy_data(struct device *dev, void *data)
848 {
849 	struct power_supply *psy;
850 	struct power_supply *ext = dev_get_drvdata(dev);
851 	const char **supplicants = (const char **)ext->supplied_to;
852 	struct ab8500_btemp *di;
853 	union power_supply_propval ret;
854 	int j;
855 
856 	psy = (struct power_supply *)data;
857 	di = power_supply_get_drvdata(psy);
858 
859 	/*
860 	 * For all psy where the name of your driver
861 	 * appears in any supplied_to
862 	 */
863 	j = match_string(supplicants, ext->num_supplicants, psy->desc->name);
864 	if (j < 0)
865 		return 0;
866 
867 	/* Go through all properties for the psy */
868 	for (j = 0; j < ext->desc->num_properties; j++) {
869 		enum power_supply_property prop;
870 		prop = ext->desc->properties[j];
871 
872 		if (power_supply_get_property(ext, prop, &ret))
873 			continue;
874 
875 		switch (prop) {
876 		case POWER_SUPPLY_PROP_PRESENT:
877 			switch (ext->desc->type) {
878 			case POWER_SUPPLY_TYPE_MAINS:
879 				/* AC disconnected */
880 				if (!ret.intval && di->events.ac_conn) {
881 					di->events.ac_conn = false;
882 				}
883 				/* AC connected */
884 				else if (ret.intval && !di->events.ac_conn) {
885 					di->events.ac_conn = true;
886 					if (!di->events.usb_conn)
887 						ab8500_btemp_periodic(di, true);
888 				}
889 				break;
890 			case POWER_SUPPLY_TYPE_USB:
891 				/* USB disconnected */
892 				if (!ret.intval && di->events.usb_conn) {
893 					di->events.usb_conn = false;
894 				}
895 				/* USB connected */
896 				else if (ret.intval && !di->events.usb_conn) {
897 					di->events.usb_conn = true;
898 					if (!di->events.ac_conn)
899 						ab8500_btemp_periodic(di, true);
900 				}
901 				break;
902 			default:
903 				break;
904 			}
905 			break;
906 		default:
907 			break;
908 		}
909 	}
910 	return 0;
911 }
912 
913 /**
914  * ab8500_btemp_external_power_changed() - callback for power supply changes
915  * @psy:       pointer to the structure power_supply
916  *
917  * This function is pointing to the function pointer external_power_changed
918  * of the structure power_supply.
919  * This function gets executed when there is a change in the external power
920  * supply to the btemp.
921  */
922 static void ab8500_btemp_external_power_changed(struct power_supply *psy)
923 {
924 	struct ab8500_btemp *di = power_supply_get_drvdata(psy);
925 
926 	class_for_each_device(power_supply_class, NULL,
927 		di->btemp_psy, ab8500_btemp_get_ext_psy_data);
928 }
929 
930 /* ab8500 btemp driver interrupts and their respective isr */
931 static struct ab8500_btemp_interrupts ab8500_btemp_irq[] = {
932 	{"BAT_CTRL_INDB", ab8500_btemp_batctrlindb_handler},
933 	{"BTEMP_LOW", ab8500_btemp_templow_handler},
934 	{"BTEMP_HIGH", ab8500_btemp_temphigh_handler},
935 	{"BTEMP_LOW_MEDIUM", ab8500_btemp_lowmed_handler},
936 	{"BTEMP_MEDIUM_HIGH", ab8500_btemp_medhigh_handler},
937 };
938 
939 static int __maybe_unused ab8500_btemp_resume(struct device *dev)
940 {
941 	struct ab8500_btemp *di = dev_get_drvdata(dev);
942 
943 	ab8500_btemp_periodic(di, true);
944 
945 	return 0;
946 }
947 
948 static int __maybe_unused ab8500_btemp_suspend(struct device *dev)
949 {
950 	struct ab8500_btemp *di = dev_get_drvdata(dev);
951 
952 	ab8500_btemp_periodic(di, false);
953 
954 	return 0;
955 }
956 
957 static int ab8500_btemp_remove(struct platform_device *pdev)
958 {
959 	struct ab8500_btemp *di = platform_get_drvdata(pdev);
960 	int i, irq;
961 
962 	/* Disable interrupts */
963 	for (i = 0; i < ARRAY_SIZE(ab8500_btemp_irq); i++) {
964 		irq = platform_get_irq_byname(pdev, ab8500_btemp_irq[i].name);
965 		free_irq(irq, di);
966 	}
967 
968 	/* Delete the work queue */
969 	destroy_workqueue(di->btemp_wq);
970 
971 	flush_scheduled_work();
972 	power_supply_unregister(di->btemp_psy);
973 
974 	return 0;
975 }
976 
977 static char *supply_interface[] = {
978 	"ab8500_chargalg",
979 	"ab8500_fg",
980 };
981 
982 static const struct power_supply_desc ab8500_btemp_desc = {
983 	.name			= "ab8500_btemp",
984 	.type			= POWER_SUPPLY_TYPE_BATTERY,
985 	.properties		= ab8500_btemp_props,
986 	.num_properties		= ARRAY_SIZE(ab8500_btemp_props),
987 	.get_property		= ab8500_btemp_get_property,
988 	.external_power_changed	= ab8500_btemp_external_power_changed,
989 };
990 
991 static int ab8500_btemp_probe(struct platform_device *pdev)
992 {
993 	struct device_node *np = pdev->dev.of_node;
994 	struct abx500_bm_data *plat = pdev->dev.platform_data;
995 	struct power_supply_config psy_cfg = {};
996 	struct device *dev = &pdev->dev;
997 	struct ab8500_btemp *di;
998 	int irq, i, ret = 0;
999 	u8 val;
1000 
1001 	di = devm_kzalloc(dev, sizeof(*di), GFP_KERNEL);
1002 	if (!di)
1003 		return -ENOMEM;
1004 
1005 	if (!plat) {
1006 		dev_err(dev, "no battery management data supplied\n");
1007 		return -EINVAL;
1008 	}
1009 	di->bm = plat;
1010 
1011 	if (np) {
1012 		ret = ab8500_bm_of_probe(dev, np, di->bm);
1013 		if (ret) {
1014 			dev_err(dev, "failed to get battery information\n");
1015 			return ret;
1016 		}
1017 	}
1018 
1019 	/* get parent data */
1020 	di->dev = dev;
1021 	di->parent = dev_get_drvdata(pdev->dev.parent);
1022 
1023 	/* Get ADC channels */
1024 	di->btemp_ball = devm_iio_channel_get(dev, "btemp_ball");
1025 	if (IS_ERR(di->btemp_ball)) {
1026 		ret = dev_err_probe(dev, PTR_ERR(di->btemp_ball),
1027 				    "failed to get BTEMP BALL ADC channel\n");
1028 		return ret;
1029 	}
1030 	di->bat_ctrl = devm_iio_channel_get(dev, "bat_ctrl");
1031 	if (IS_ERR(di->bat_ctrl)) {
1032 		ret = dev_err_probe(dev, PTR_ERR(di->bat_ctrl),
1033 				    "failed to get BAT CTRL ADC channel\n");
1034 		return ret;
1035 	}
1036 
1037 	di->initialized = false;
1038 
1039 	psy_cfg.supplied_to = supply_interface;
1040 	psy_cfg.num_supplicants = ARRAY_SIZE(supply_interface);
1041 	psy_cfg.drv_data = di;
1042 
1043 	/* Create a work queue for the btemp */
1044 	di->btemp_wq =
1045 		alloc_workqueue("ab8500_btemp_wq", WQ_MEM_RECLAIM, 0);
1046 	if (di->btemp_wq == NULL) {
1047 		dev_err(dev, "failed to create work queue\n");
1048 		return -ENOMEM;
1049 	}
1050 
1051 	/* Init work for measuring temperature periodically */
1052 	INIT_DEFERRABLE_WORK(&di->btemp_periodic_work,
1053 		ab8500_btemp_periodic_work);
1054 
1055 	/* Set BTEMP thermal limits. Low and Med are fixed */
1056 	di->btemp_ranges.btemp_low_limit = BTEMP_THERMAL_LOW_LIMIT;
1057 	di->btemp_ranges.btemp_med_limit = BTEMP_THERMAL_MED_LIMIT;
1058 
1059 	ret = abx500_get_register_interruptible(dev, AB8500_CHARGER,
1060 		AB8500_BTEMP_HIGH_TH, &val);
1061 	if (ret < 0) {
1062 		dev_err(dev, "%s ab8500 read failed\n", __func__);
1063 		goto free_btemp_wq;
1064 	}
1065 	switch (val) {
1066 	case BTEMP_HIGH_TH_57_0:
1067 	case BTEMP_HIGH_TH_57_1:
1068 		di->btemp_ranges.btemp_high_limit =
1069 			BTEMP_THERMAL_HIGH_LIMIT_57;
1070 		break;
1071 	case BTEMP_HIGH_TH_52:
1072 		di->btemp_ranges.btemp_high_limit =
1073 			BTEMP_THERMAL_HIGH_LIMIT_52;
1074 		break;
1075 	case BTEMP_HIGH_TH_62:
1076 		di->btemp_ranges.btemp_high_limit =
1077 			BTEMP_THERMAL_HIGH_LIMIT_62;
1078 		break;
1079 	}
1080 
1081 	/* Register BTEMP power supply class */
1082 	di->btemp_psy = power_supply_register(dev, &ab8500_btemp_desc,
1083 					      &psy_cfg);
1084 	if (IS_ERR(di->btemp_psy)) {
1085 		dev_err(dev, "failed to register BTEMP psy\n");
1086 		ret = PTR_ERR(di->btemp_psy);
1087 		goto free_btemp_wq;
1088 	}
1089 
1090 	/* Register interrupts */
1091 	for (i = 0; i < ARRAY_SIZE(ab8500_btemp_irq); i++) {
1092 		irq = platform_get_irq_byname(pdev, ab8500_btemp_irq[i].name);
1093 		if (irq < 0) {
1094 			ret = irq;
1095 			goto free_irq;
1096 		}
1097 
1098 		ret = request_threaded_irq(irq, NULL, ab8500_btemp_irq[i].isr,
1099 			IRQF_SHARED | IRQF_NO_SUSPEND | IRQF_ONESHOT,
1100 			ab8500_btemp_irq[i].name, di);
1101 
1102 		if (ret) {
1103 			dev_err(dev, "failed to request %s IRQ %d: %d\n"
1104 				, ab8500_btemp_irq[i].name, irq, ret);
1105 			goto free_irq;
1106 		}
1107 		dev_dbg(dev, "Requested %s IRQ %d: %d\n",
1108 			ab8500_btemp_irq[i].name, irq, ret);
1109 	}
1110 
1111 	platform_set_drvdata(pdev, di);
1112 
1113 	/* Kick off periodic temperature measurements */
1114 	ab8500_btemp_periodic(di, true);
1115 	list_add_tail(&di->node, &ab8500_btemp_list);
1116 
1117 	return ret;
1118 
1119 free_irq:
1120 	/* We also have to free all successfully registered irqs */
1121 	for (i = i - 1; i >= 0; i--) {
1122 		irq = platform_get_irq_byname(pdev, ab8500_btemp_irq[i].name);
1123 		free_irq(irq, di);
1124 	}
1125 
1126 	power_supply_unregister(di->btemp_psy);
1127 free_btemp_wq:
1128 	destroy_workqueue(di->btemp_wq);
1129 	return ret;
1130 }
1131 
1132 static SIMPLE_DEV_PM_OPS(ab8500_btemp_pm_ops, ab8500_btemp_suspend, ab8500_btemp_resume);
1133 
1134 static const struct of_device_id ab8500_btemp_match[] = {
1135 	{ .compatible = "stericsson,ab8500-btemp", },
1136 	{ },
1137 };
1138 
1139 static struct platform_driver ab8500_btemp_driver = {
1140 	.probe = ab8500_btemp_probe,
1141 	.remove = ab8500_btemp_remove,
1142 	.driver = {
1143 		.name = "ab8500-btemp",
1144 		.of_match_table = ab8500_btemp_match,
1145 		.pm = &ab8500_btemp_pm_ops,
1146 	},
1147 };
1148 
1149 static int __init ab8500_btemp_init(void)
1150 {
1151 	return platform_driver_register(&ab8500_btemp_driver);
1152 }
1153 
1154 static void __exit ab8500_btemp_exit(void)
1155 {
1156 	platform_driver_unregister(&ab8500_btemp_driver);
1157 }
1158 
1159 device_initcall(ab8500_btemp_init);
1160 module_exit(ab8500_btemp_exit);
1161 
1162 MODULE_LICENSE("GPL v2");
1163 MODULE_AUTHOR("Johan Palsson, Karl Komierowski, Arun R Murthy");
1164 MODULE_ALIAS("platform:ab8500-btemp");
1165 MODULE_DESCRIPTION("AB8500 battery temperature driver");
1166