1 /*
2  * Copyright (C) ST-Ericsson SA 2012
3  *
4  * Battery temperature driver for AB8500
5  *
6  * License Terms: GNU General Public License v2
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/mfd/abx500/ab8500-gpadc.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  * @gpadc:		Pointer to the struct gpadc
83  * @fg:			Pointer to the struct fg
84  * @bm:           	Platform specific battery management information
85  * @btemp_psy:		Structure for BTEMP specific battery properties
86  * @events:		Structure for information about events triggered
87  * @btemp_ranges:	Battery temperature range structure
88  * @btemp_wq:		Work queue for measuring the temperature periodically
89  * @btemp_periodic_work:	Work for measuring the temperature periodically
90  * @initialized:	True if battery id read.
91  */
92 struct ab8500_btemp {
93 	struct device *dev;
94 	struct list_head node;
95 	int curr_source;
96 	int bat_temp;
97 	int prev_bat_temp;
98 	struct ab8500 *parent;
99 	struct ab8500_gpadc *gpadc;
100 	struct ab8500_fg *fg;
101 	struct abx500_bm_data *bm;
102 	struct power_supply *btemp_psy;
103 	struct ab8500_btemp_events events;
104 	struct ab8500_btemp_ranges btemp_ranges;
105 	struct workqueue_struct *btemp_wq;
106 	struct delayed_work btemp_periodic_work;
107 	bool initialized;
108 };
109 
110 /* BTEMP power supply properties */
111 static enum power_supply_property ab8500_btemp_props[] = {
112 	POWER_SUPPLY_PROP_PRESENT,
113 	POWER_SUPPLY_PROP_ONLINE,
114 	POWER_SUPPLY_PROP_TECHNOLOGY,
115 	POWER_SUPPLY_PROP_TEMP,
116 };
117 
118 static LIST_HEAD(ab8500_btemp_list);
119 
120 /**
121  * ab8500_btemp_get() - returns a reference to the primary AB8500 BTEMP
122  * (i.e. the first BTEMP in the instance list)
123  */
124 struct ab8500_btemp *ab8500_btemp_get(void)
125 {
126 	return list_first_entry(&ab8500_btemp_list, struct ab8500_btemp, node);
127 }
128 EXPORT_SYMBOL(ab8500_btemp_get);
129 
130 /**
131  * ab8500_btemp_batctrl_volt_to_res() - convert batctrl voltage to resistance
132  * @di:		pointer to the ab8500_btemp structure
133  * @v_batctrl:	measured batctrl voltage
134  * @inst_curr:	measured instant current
135  *
136  * This function returns the battery resistance that is
137  * derived from the BATCTRL voltage.
138  * Returns value in Ohms.
139  */
140 static int ab8500_btemp_batctrl_volt_to_res(struct ab8500_btemp *di,
141 	int v_batctrl, int inst_curr)
142 {
143 	int rbs;
144 
145 	if (is_ab8500_1p1_or_earlier(di->parent)) {
146 		/*
147 		 * For ABB cut1.0 and 1.1 BAT_CTRL is internally
148 		 * connected to 1.8V through a 450k resistor
149 		 */
150 		return (450000 * (v_batctrl)) / (1800 - v_batctrl);
151 	}
152 
153 	if (di->bm->adc_therm == ABx500_ADC_THERM_BATCTRL) {
154 		/*
155 		 * If the battery has internal NTC, we use the current
156 		 * source to calculate the resistance.
157 		 */
158 		rbs = (v_batctrl * 1000
159 		       - di->bm->gnd_lift_resistance * inst_curr)
160 		      / di->curr_source;
161 	} else {
162 		/*
163 		 * BAT_CTRL is internally
164 		 * connected to 1.8V through a 80k resistor
165 		 */
166 		rbs = (80000 * (v_batctrl)) / (1800 - v_batctrl);
167 	}
168 
169 	return rbs;
170 }
171 
172 /**
173  * ab8500_btemp_read_batctrl_voltage() - measure batctrl voltage
174  * @di:		pointer to the ab8500_btemp structure
175  *
176  * This function returns the voltage on BATCTRL. Returns value in mV.
177  */
178 static int ab8500_btemp_read_batctrl_voltage(struct ab8500_btemp *di)
179 {
180 	int vbtemp;
181 	static int prev;
182 
183 	vbtemp = ab8500_gpadc_convert(di->gpadc, BAT_CTRL);
184 	if (vbtemp < 0) {
185 		dev_err(di->dev,
186 			"%s gpadc conversion failed, using previous value",
187 			__func__);
188 		return prev;
189 	}
190 	prev = vbtemp;
191 	return vbtemp;
192 }
193 
194 /**
195  * ab8500_btemp_curr_source_enable() - enable/disable batctrl current source
196  * @di:		pointer to the ab8500_btemp structure
197  * @enable:	enable or disable the current source
198  *
199  * Enable or disable the current sources for the BatCtrl AD channel
200  */
201 static int ab8500_btemp_curr_source_enable(struct ab8500_btemp *di,
202 	bool enable)
203 {
204 	int curr;
205 	int ret = 0;
206 
207 	/*
208 	 * BATCTRL current sources are included on AB8500 cut2.0
209 	 * and future versions
210 	 */
211 	if (is_ab8500_1p1_or_earlier(di->parent))
212 		return 0;
213 
214 	/* Only do this for batteries with internal NTC */
215 	if (di->bm->adc_therm == ABx500_ADC_THERM_BATCTRL && enable) {
216 
217 		if (is_ab8540(di->parent)) {
218 			if (di->curr_source == BTEMP_BATCTRL_CURR_SRC_60UA)
219 				curr = BAT_CTRL_60U_ENA;
220 			else
221 				curr = BAT_CTRL_120U_ENA;
222 		} else if (is_ab9540(di->parent) || is_ab8505(di->parent)) {
223 			if (di->curr_source == BTEMP_BATCTRL_CURR_SRC_16UA)
224 				curr = BAT_CTRL_16U_ENA;
225 			else
226 				curr = BAT_CTRL_18U_ENA;
227 		} else {
228 			if (di->curr_source == BTEMP_BATCTRL_CURR_SRC_7UA)
229 				curr = BAT_CTRL_7U_ENA;
230 			else
231 				curr = BAT_CTRL_20U_ENA;
232 		}
233 
234 		dev_dbg(di->dev, "Set BATCTRL %duA\n", di->curr_source);
235 
236 		ret = abx500_mask_and_set_register_interruptible(di->dev,
237 			AB8500_CHARGER, AB8500_BAT_CTRL_CURRENT_SOURCE,
238 			FORCE_BAT_CTRL_CMP_HIGH, FORCE_BAT_CTRL_CMP_HIGH);
239 		if (ret) {
240 			dev_err(di->dev, "%s failed setting cmp_force\n",
241 				__func__);
242 			return ret;
243 		}
244 
245 		/*
246 		 * We have to wait one 32kHz cycle before enabling
247 		 * the current source, since ForceBatCtrlCmpHigh needs
248 		 * to be written in a separate cycle
249 		 */
250 		udelay(32);
251 
252 		ret = abx500_set_register_interruptible(di->dev,
253 			AB8500_CHARGER, AB8500_BAT_CTRL_CURRENT_SOURCE,
254 			FORCE_BAT_CTRL_CMP_HIGH | curr);
255 		if (ret) {
256 			dev_err(di->dev, "%s failed enabling current source\n",
257 				__func__);
258 			goto disable_curr_source;
259 		}
260 	} else if (di->bm->adc_therm == ABx500_ADC_THERM_BATCTRL && !enable) {
261 		dev_dbg(di->dev, "Disable BATCTRL curr source\n");
262 
263 		if (is_ab8540(di->parent)) {
264 			/* Write 0 to the curr bits */
265 			ret = abx500_mask_and_set_register_interruptible(
266 				di->dev,
267 				AB8500_CHARGER, AB8500_BAT_CTRL_CURRENT_SOURCE,
268 				BAT_CTRL_60U_ENA | BAT_CTRL_120U_ENA,
269 				~(BAT_CTRL_60U_ENA | BAT_CTRL_120U_ENA));
270 		} else if (is_ab9540(di->parent) || is_ab8505(di->parent)) {
271 			/* Write 0 to the curr bits */
272 			ret = abx500_mask_and_set_register_interruptible(
273 				di->dev,
274 				AB8500_CHARGER, AB8500_BAT_CTRL_CURRENT_SOURCE,
275 				BAT_CTRL_16U_ENA | BAT_CTRL_18U_ENA,
276 				~(BAT_CTRL_16U_ENA | BAT_CTRL_18U_ENA));
277 		} else {
278 			/* Write 0 to the curr bits */
279 			ret = abx500_mask_and_set_register_interruptible(
280 				di->dev,
281 				AB8500_CHARGER, AB8500_BAT_CTRL_CURRENT_SOURCE,
282 				BAT_CTRL_7U_ENA | BAT_CTRL_20U_ENA,
283 				~(BAT_CTRL_7U_ENA | BAT_CTRL_20U_ENA));
284 		}
285 
286 		if (ret) {
287 			dev_err(di->dev, "%s failed disabling current source\n",
288 				__func__);
289 			goto disable_curr_source;
290 		}
291 
292 		/* Enable Pull-Up and comparator */
293 		ret = abx500_mask_and_set_register_interruptible(di->dev,
294 			AB8500_CHARGER,	AB8500_BAT_CTRL_CURRENT_SOURCE,
295 			BAT_CTRL_PULL_UP_ENA | BAT_CTRL_CMP_ENA,
296 			BAT_CTRL_PULL_UP_ENA | BAT_CTRL_CMP_ENA);
297 		if (ret) {
298 			dev_err(di->dev, "%s failed enabling PU and comp\n",
299 				__func__);
300 			goto enable_pu_comp;
301 		}
302 
303 		/*
304 		 * We have to wait one 32kHz cycle before disabling
305 		 * ForceBatCtrlCmpHigh since this needs to be written
306 		 * in a separate cycle
307 		 */
308 		udelay(32);
309 
310 		/* Disable 'force comparator' */
311 		ret = abx500_mask_and_set_register_interruptible(di->dev,
312 			AB8500_CHARGER, AB8500_BAT_CTRL_CURRENT_SOURCE,
313 			FORCE_BAT_CTRL_CMP_HIGH, ~FORCE_BAT_CTRL_CMP_HIGH);
314 		if (ret) {
315 			dev_err(di->dev, "%s failed disabling force comp\n",
316 				__func__);
317 			goto disable_force_comp;
318 		}
319 	}
320 	return ret;
321 
322 	/*
323 	 * We have to try unsetting FORCE_BAT_CTRL_CMP_HIGH one more time
324 	 * if we got an error above
325 	 */
326 disable_curr_source:
327 	if (is_ab8540(di->parent)) {
328 		/* Write 0 to the curr bits */
329 		ret = abx500_mask_and_set_register_interruptible(di->dev,
330 			AB8500_CHARGER, AB8500_BAT_CTRL_CURRENT_SOURCE,
331 			BAT_CTRL_60U_ENA | BAT_CTRL_120U_ENA,
332 			~(BAT_CTRL_60U_ENA | BAT_CTRL_120U_ENA));
333 	} else if (is_ab9540(di->parent) || is_ab8505(di->parent)) {
334 		/* Write 0 to the curr bits */
335 		ret = abx500_mask_and_set_register_interruptible(di->dev,
336 			AB8500_CHARGER, AB8500_BAT_CTRL_CURRENT_SOURCE,
337 			BAT_CTRL_16U_ENA | BAT_CTRL_18U_ENA,
338 			~(BAT_CTRL_16U_ENA | BAT_CTRL_18U_ENA));
339 	} else {
340 		/* Write 0 to the curr bits */
341 		ret = abx500_mask_and_set_register_interruptible(di->dev,
342 			AB8500_CHARGER, AB8500_BAT_CTRL_CURRENT_SOURCE,
343 			BAT_CTRL_7U_ENA | BAT_CTRL_20U_ENA,
344 			~(BAT_CTRL_7U_ENA | BAT_CTRL_20U_ENA));
345 	}
346 
347 	if (ret) {
348 		dev_err(di->dev, "%s failed disabling current source\n",
349 			__func__);
350 		return ret;
351 	}
352 enable_pu_comp:
353 	/* Enable Pull-Up and comparator */
354 	ret = abx500_mask_and_set_register_interruptible(di->dev,
355 		AB8500_CHARGER,	AB8500_BAT_CTRL_CURRENT_SOURCE,
356 		BAT_CTRL_PULL_UP_ENA | BAT_CTRL_CMP_ENA,
357 		BAT_CTRL_PULL_UP_ENA | BAT_CTRL_CMP_ENA);
358 	if (ret) {
359 		dev_err(di->dev, "%s failed enabling PU and comp\n",
360 			__func__);
361 		return ret;
362 	}
363 
364 disable_force_comp:
365 	/*
366 	 * We have to wait one 32kHz cycle before disabling
367 	 * ForceBatCtrlCmpHigh since this needs to be written
368 	 * in a separate cycle
369 	 */
370 	udelay(32);
371 
372 	/* Disable 'force comparator' */
373 	ret = abx500_mask_and_set_register_interruptible(di->dev,
374 		AB8500_CHARGER, AB8500_BAT_CTRL_CURRENT_SOURCE,
375 		FORCE_BAT_CTRL_CMP_HIGH, ~FORCE_BAT_CTRL_CMP_HIGH);
376 	if (ret) {
377 		dev_err(di->dev, "%s failed disabling force comp\n",
378 			__func__);
379 		return ret;
380 	}
381 
382 	return ret;
383 }
384 
385 /**
386  * ab8500_btemp_get_batctrl_res() - get battery resistance
387  * @di:		pointer to the ab8500_btemp structure
388  *
389  * This function returns the battery pack identification resistance.
390  * Returns value in Ohms.
391  */
392 static int ab8500_btemp_get_batctrl_res(struct ab8500_btemp *di)
393 {
394 	int ret;
395 	int batctrl = 0;
396 	int res;
397 	int inst_curr;
398 	int i;
399 
400 	/*
401 	 * BATCTRL current sources are included on AB8500 cut2.0
402 	 * and future versions
403 	 */
404 	ret = ab8500_btemp_curr_source_enable(di, true);
405 	if (ret) {
406 		dev_err(di->dev, "%s curr source enabled failed\n", __func__);
407 		return ret;
408 	}
409 
410 	if (!di->fg)
411 		di->fg = ab8500_fg_get();
412 	if (!di->fg) {
413 		dev_err(di->dev, "No fg found\n");
414 		return -EINVAL;
415 	}
416 
417 	ret = ab8500_fg_inst_curr_start(di->fg);
418 
419 	if (ret) {
420 		dev_err(di->dev, "Failed to start current measurement\n");
421 		return ret;
422 	}
423 
424 	do {
425 		msleep(20);
426 	} while (!ab8500_fg_inst_curr_started(di->fg));
427 
428 	i = 0;
429 
430 	do {
431 		batctrl += ab8500_btemp_read_batctrl_voltage(di);
432 		i++;
433 		msleep(20);
434 	} while (!ab8500_fg_inst_curr_done(di->fg));
435 	batctrl /= i;
436 
437 	ret = ab8500_fg_inst_curr_finalize(di->fg, &inst_curr);
438 	if (ret) {
439 		dev_err(di->dev, "Failed to finalize current measurement\n");
440 		return ret;
441 	}
442 
443 	res = ab8500_btemp_batctrl_volt_to_res(di, batctrl, inst_curr);
444 
445 	ret = ab8500_btemp_curr_source_enable(di, false);
446 	if (ret) {
447 		dev_err(di->dev, "%s curr source disable failed\n", __func__);
448 		return ret;
449 	}
450 
451 	dev_dbg(di->dev, "%s batctrl: %d res: %d inst_curr: %d samples: %d\n",
452 		__func__, batctrl, res, inst_curr, i);
453 
454 	return res;
455 }
456 
457 /**
458  * ab8500_btemp_res_to_temp() - resistance to temperature
459  * @di:		pointer to the ab8500_btemp structure
460  * @tbl:	pointer to the resiatance to temperature table
461  * @tbl_size:	size of the resistance to temperature table
462  * @res:	resistance to calculate the temperature from
463  *
464  * This function returns the battery temperature in degrees Celsius
465  * based on the NTC resistance.
466  */
467 static int ab8500_btemp_res_to_temp(struct ab8500_btemp *di,
468 	const struct abx500_res_to_temp *tbl, int tbl_size, int res)
469 {
470 	int i;
471 	/*
472 	 * Calculate the formula for the straight line
473 	 * Simple interpolation if we are within
474 	 * the resistance table limits, extrapolate
475 	 * if resistance is outside the limits.
476 	 */
477 	if (res > tbl[0].resist)
478 		i = 0;
479 	else if (res <= tbl[tbl_size - 1].resist)
480 		i = tbl_size - 2;
481 	else {
482 		i = 0;
483 		while (!(res <= tbl[i].resist &&
484 			res > tbl[i + 1].resist))
485 			i++;
486 	}
487 
488 	return tbl[i].temp + ((tbl[i + 1].temp - tbl[i].temp) *
489 		(res - tbl[i].resist)) / (tbl[i + 1].resist - tbl[i].resist);
490 }
491 
492 /**
493  * ab8500_btemp_measure_temp() - measure battery temperature
494  * @di:		pointer to the ab8500_btemp structure
495  *
496  * Returns battery temperature (on success) else the previous temperature
497  */
498 static int ab8500_btemp_measure_temp(struct ab8500_btemp *di)
499 {
500 	int temp;
501 	static int prev;
502 	int rbat, rntc, vntc;
503 	u8 id;
504 
505 	id = di->bm->batt_id;
506 
507 	if (di->bm->adc_therm == ABx500_ADC_THERM_BATCTRL &&
508 			id != BATTERY_UNKNOWN) {
509 
510 		rbat = ab8500_btemp_get_batctrl_res(di);
511 		if (rbat < 0) {
512 			dev_err(di->dev, "%s get batctrl res failed\n",
513 				__func__);
514 			/*
515 			 * Return out-of-range temperature so that
516 			 * charging is stopped
517 			 */
518 			return BTEMP_THERMAL_LOW_LIMIT;
519 		}
520 
521 		temp = ab8500_btemp_res_to_temp(di,
522 			di->bm->bat_type[id].r_to_t_tbl,
523 			di->bm->bat_type[id].n_temp_tbl_elements, rbat);
524 	} else {
525 		vntc = ab8500_gpadc_convert(di->gpadc, BTEMP_BALL);
526 		if (vntc < 0) {
527 			dev_err(di->dev,
528 				"%s gpadc conversion failed,"
529 				" using previous value\n", __func__);
530 			return prev;
531 		}
532 		/*
533 		 * The PCB NTC is sourced from VTVOUT via a 230kOhm
534 		 * resistor.
535 		 */
536 		rntc = 230000 * vntc / (VTVOUT_V - vntc);
537 
538 		temp = ab8500_btemp_res_to_temp(di,
539 			di->bm->bat_type[id].r_to_t_tbl,
540 			di->bm->bat_type[id].n_temp_tbl_elements, rntc);
541 		prev = temp;
542 	}
543 	dev_dbg(di->dev, "Battery temperature is %d\n", temp);
544 	return temp;
545 }
546 
547 /**
548  * ab8500_btemp_id() - Identify the connected battery
549  * @di:		pointer to the ab8500_btemp structure
550  *
551  * This function will try to identify the battery by reading the ID
552  * resistor. Some brands use a combined ID resistor with a NTC resistor to
553  * both be able to identify and to read the temperature of it.
554  */
555 static int ab8500_btemp_id(struct ab8500_btemp *di)
556 {
557 	int res;
558 	u8 i;
559 	if (is_ab8540(di->parent))
560 		di->curr_source = BTEMP_BATCTRL_CURR_SRC_60UA;
561 	else if (is_ab9540(di->parent) || is_ab8505(di->parent))
562 		di->curr_source = BTEMP_BATCTRL_CURR_SRC_16UA;
563 	else
564 		di->curr_source = BTEMP_BATCTRL_CURR_SRC_7UA;
565 
566 	di->bm->batt_id = BATTERY_UNKNOWN;
567 
568 	res =  ab8500_btemp_get_batctrl_res(di);
569 	if (res < 0) {
570 		dev_err(di->dev, "%s get batctrl res failed\n", __func__);
571 		return -ENXIO;
572 	}
573 
574 	/* BATTERY_UNKNOWN is defined on position 0, skip it! */
575 	for (i = BATTERY_UNKNOWN + 1; i < di->bm->n_btypes; i++) {
576 		if ((res <= di->bm->bat_type[i].resis_high) &&
577 			(res >= di->bm->bat_type[i].resis_low)) {
578 			dev_dbg(di->dev, "Battery detected on %s"
579 				" low %d < res %d < high: %d"
580 				" index: %d\n",
581 				di->bm->adc_therm == ABx500_ADC_THERM_BATCTRL ?
582 				"BATCTRL" : "BATTEMP",
583 				di->bm->bat_type[i].resis_low, res,
584 				di->bm->bat_type[i].resis_high, i);
585 
586 			di->bm->batt_id = i;
587 			break;
588 		}
589 	}
590 
591 	if (di->bm->batt_id == BATTERY_UNKNOWN) {
592 		dev_warn(di->dev, "Battery identified as unknown"
593 			", resistance %d Ohm\n", res);
594 		return -ENXIO;
595 	}
596 
597 	/*
598 	 * We only have to change current source if the
599 	 * detected type is Type 1.
600 	 */
601 	if (di->bm->adc_therm == ABx500_ADC_THERM_BATCTRL &&
602 	    di->bm->batt_id == 1) {
603 		if (is_ab8540(di->parent)) {
604 			dev_dbg(di->dev,
605 				"Set BATCTRL current source to 60uA\n");
606 			di->curr_source = BTEMP_BATCTRL_CURR_SRC_60UA;
607 		} else if (is_ab9540(di->parent) || is_ab8505(di->parent)) {
608 			dev_dbg(di->dev,
609 				"Set BATCTRL current source to 16uA\n");
610 			di->curr_source = BTEMP_BATCTRL_CURR_SRC_16UA;
611 		} else {
612 			dev_dbg(di->dev, "Set BATCTRL current source to 20uA\n");
613 			di->curr_source = BTEMP_BATCTRL_CURR_SRC_20UA;
614 		}
615 	}
616 
617 	return di->bm->batt_id;
618 }
619 
620 /**
621  * ab8500_btemp_periodic_work() - Measuring the temperature periodically
622  * @work:	pointer to the work_struct structure
623  *
624  * Work function for measuring the temperature periodically
625  */
626 static void ab8500_btemp_periodic_work(struct work_struct *work)
627 {
628 	int interval;
629 	int bat_temp;
630 	struct ab8500_btemp *di = container_of(work,
631 		struct ab8500_btemp, btemp_periodic_work.work);
632 
633 	if (!di->initialized) {
634 		/* Identify the battery */
635 		if (ab8500_btemp_id(di) < 0)
636 			dev_warn(di->dev, "failed to identify the battery\n");
637 	}
638 
639 	bat_temp = ab8500_btemp_measure_temp(di);
640 	/*
641 	 * Filter battery temperature.
642 	 * Allow direct updates on temperature only if two samples result in
643 	 * same temperature. Else only allow 1 degree change from previous
644 	 * reported value in the direction of the new measurement.
645 	 */
646 	if ((bat_temp == di->prev_bat_temp) || !di->initialized) {
647 		if ((di->bat_temp != di->prev_bat_temp) || !di->initialized) {
648 			di->initialized = true;
649 			di->bat_temp = bat_temp;
650 			power_supply_changed(di->btemp_psy);
651 		}
652 	} else if (bat_temp < di->prev_bat_temp) {
653 		di->bat_temp--;
654 		power_supply_changed(di->btemp_psy);
655 	} else if (bat_temp > di->prev_bat_temp) {
656 		di->bat_temp++;
657 		power_supply_changed(di->btemp_psy);
658 	}
659 	di->prev_bat_temp = bat_temp;
660 
661 	if (di->events.ac_conn || di->events.usb_conn)
662 		interval = di->bm->temp_interval_chg;
663 	else
664 		interval = di->bm->temp_interval_nochg;
665 
666 	/* Schedule a new measurement */
667 	queue_delayed_work(di->btemp_wq,
668 		&di->btemp_periodic_work,
669 		round_jiffies(interval * HZ));
670 }
671 
672 /**
673  * ab8500_btemp_batctrlindb_handler() - battery removal detected
674  * @irq:       interrupt number
675  * @_di:       void pointer that has to address of ab8500_btemp
676  *
677  * Returns IRQ status(IRQ_HANDLED)
678  */
679 static irqreturn_t ab8500_btemp_batctrlindb_handler(int irq, void *_di)
680 {
681 	struct ab8500_btemp *di = _di;
682 	dev_err(di->dev, "Battery removal detected!\n");
683 
684 	di->events.batt_rem = true;
685 	power_supply_changed(di->btemp_psy);
686 
687 	return IRQ_HANDLED;
688 }
689 
690 /**
691  * ab8500_btemp_templow_handler() - battery temp lower than 10 degrees
692  * @irq:       interrupt number
693  * @_di:       void pointer that has to address of ab8500_btemp
694  *
695  * Returns IRQ status(IRQ_HANDLED)
696  */
697 static irqreturn_t ab8500_btemp_templow_handler(int irq, void *_di)
698 {
699 	struct ab8500_btemp *di = _di;
700 
701 	if (is_ab8500_3p3_or_earlier(di->parent)) {
702 		dev_dbg(di->dev, "Ignore false btemp low irq"
703 			" for ABB cut 1.0, 1.1, 2.0 and 3.3\n");
704 	} else {
705 		dev_crit(di->dev, "Battery temperature lower than -10deg c\n");
706 
707 		di->events.btemp_low = true;
708 		di->events.btemp_high = false;
709 		di->events.btemp_medhigh = false;
710 		di->events.btemp_lowmed = false;
711 		power_supply_changed(di->btemp_psy);
712 	}
713 
714 	return IRQ_HANDLED;
715 }
716 
717 /**
718  * ab8500_btemp_temphigh_handler() - battery temp higher than max temp
719  * @irq:       interrupt number
720  * @_di:       void pointer that has to address of ab8500_btemp
721  *
722  * Returns IRQ status(IRQ_HANDLED)
723  */
724 static irqreturn_t ab8500_btemp_temphigh_handler(int irq, void *_di)
725 {
726 	struct ab8500_btemp *di = _di;
727 
728 	dev_crit(di->dev, "Battery temperature is higher than MAX temp\n");
729 
730 	di->events.btemp_high = true;
731 	di->events.btemp_medhigh = false;
732 	di->events.btemp_lowmed = false;
733 	di->events.btemp_low = false;
734 	power_supply_changed(di->btemp_psy);
735 
736 	return IRQ_HANDLED;
737 }
738 
739 /**
740  * ab8500_btemp_lowmed_handler() - battery temp between low and medium
741  * @irq:       interrupt number
742  * @_di:       void pointer that has to address of ab8500_btemp
743  *
744  * Returns IRQ status(IRQ_HANDLED)
745  */
746 static irqreturn_t ab8500_btemp_lowmed_handler(int irq, void *_di)
747 {
748 	struct ab8500_btemp *di = _di;
749 
750 	dev_dbg(di->dev, "Battery temperature is between low and medium\n");
751 
752 	di->events.btemp_lowmed = true;
753 	di->events.btemp_medhigh = false;
754 	di->events.btemp_high = false;
755 	di->events.btemp_low = false;
756 	power_supply_changed(di->btemp_psy);
757 
758 	return IRQ_HANDLED;
759 }
760 
761 /**
762  * ab8500_btemp_medhigh_handler() - battery temp between medium and high
763  * @irq:       interrupt number
764  * @_di:       void pointer that has to address of ab8500_btemp
765  *
766  * Returns IRQ status(IRQ_HANDLED)
767  */
768 static irqreturn_t ab8500_btemp_medhigh_handler(int irq, void *_di)
769 {
770 	struct ab8500_btemp *di = _di;
771 
772 	dev_dbg(di->dev, "Battery temperature is between medium and high\n");
773 
774 	di->events.btemp_medhigh = true;
775 	di->events.btemp_lowmed = false;
776 	di->events.btemp_high = false;
777 	di->events.btemp_low = false;
778 	power_supply_changed(di->btemp_psy);
779 
780 	return IRQ_HANDLED;
781 }
782 
783 /**
784  * ab8500_btemp_periodic() - Periodic temperature measurements
785  * @di:		pointer to the ab8500_btemp structure
786  * @enable:	enable or disable periodic temperature measurements
787  *
788  * Starts of stops periodic temperature measurements. Periodic measurements
789  * should only be done when a charger is connected.
790  */
791 static void ab8500_btemp_periodic(struct ab8500_btemp *di,
792 	bool enable)
793 {
794 	dev_dbg(di->dev, "Enable periodic temperature measurements: %d\n",
795 		enable);
796 	/*
797 	 * Make sure a new measurement is done directly by cancelling
798 	 * any pending work
799 	 */
800 	cancel_delayed_work_sync(&di->btemp_periodic_work);
801 
802 	if (enable)
803 		queue_delayed_work(di->btemp_wq, &di->btemp_periodic_work, 0);
804 }
805 
806 /**
807  * ab8500_btemp_get_temp() - get battery temperature
808  * @di:		pointer to the ab8500_btemp structure
809  *
810  * Returns battery temperature
811  */
812 int ab8500_btemp_get_temp(struct ab8500_btemp *di)
813 {
814 	int temp = 0;
815 
816 	/*
817 	 * The BTEMP events are not reliabe on AB8500 cut3.3
818 	 * and prior versions
819 	 */
820 	if (is_ab8500_3p3_or_earlier(di->parent)) {
821 		temp = di->bat_temp * 10;
822 	} else {
823 		if (di->events.btemp_low) {
824 			if (temp > di->btemp_ranges.btemp_low_limit)
825 				temp = di->btemp_ranges.btemp_low_limit * 10;
826 			else
827 				temp = di->bat_temp * 10;
828 		} else if (di->events.btemp_high) {
829 			if (temp < di->btemp_ranges.btemp_high_limit)
830 				temp = di->btemp_ranges.btemp_high_limit * 10;
831 			else
832 				temp = di->bat_temp * 10;
833 		} else if (di->events.btemp_lowmed) {
834 			if (temp > di->btemp_ranges.btemp_med_limit)
835 				temp = di->btemp_ranges.btemp_med_limit * 10;
836 			else
837 				temp = di->bat_temp * 10;
838 		} else if (di->events.btemp_medhigh) {
839 			if (temp < di->btemp_ranges.btemp_med_limit)
840 				temp = di->btemp_ranges.btemp_med_limit * 10;
841 			else
842 				temp = di->bat_temp * 10;
843 		} else
844 			temp = di->bat_temp * 10;
845 	}
846 	return temp;
847 }
848 EXPORT_SYMBOL(ab8500_btemp_get_temp);
849 
850 /**
851  * ab8500_btemp_get_batctrl_temp() - get the temperature
852  * @btemp:      pointer to the btemp structure
853  *
854  * Returns the batctrl temperature in millidegrees
855  */
856 int ab8500_btemp_get_batctrl_temp(struct ab8500_btemp *btemp)
857 {
858 	return btemp->bat_temp * 1000;
859 }
860 EXPORT_SYMBOL(ab8500_btemp_get_batctrl_temp);
861 
862 /**
863  * ab8500_btemp_get_property() - get the btemp properties
864  * @psy:        pointer to the power_supply structure
865  * @psp:        pointer to the power_supply_property structure
866  * @val:        pointer to the power_supply_propval union
867  *
868  * This function gets called when an application tries to get the btemp
869  * properties by reading the sysfs files.
870  * online:	presence of the battery
871  * present:	presence of the battery
872  * technology:	battery technology
873  * temp:	battery temperature
874  * Returns error code in case of failure else 0(on success)
875  */
876 static int ab8500_btemp_get_property(struct power_supply *psy,
877 	enum power_supply_property psp,
878 	union power_supply_propval *val)
879 {
880 	struct ab8500_btemp *di = power_supply_get_drvdata(psy);
881 
882 	switch (psp) {
883 	case POWER_SUPPLY_PROP_PRESENT:
884 	case POWER_SUPPLY_PROP_ONLINE:
885 		if (di->events.batt_rem)
886 			val->intval = 0;
887 		else
888 			val->intval = 1;
889 		break;
890 	case POWER_SUPPLY_PROP_TECHNOLOGY:
891 		val->intval = di->bm->bat_type[di->bm->batt_id].name;
892 		break;
893 	case POWER_SUPPLY_PROP_TEMP:
894 		val->intval = ab8500_btemp_get_temp(di);
895 		break;
896 	default:
897 		return -EINVAL;
898 	}
899 	return 0;
900 }
901 
902 static int ab8500_btemp_get_ext_psy_data(struct device *dev, void *data)
903 {
904 	struct power_supply *psy;
905 	struct power_supply *ext = dev_get_drvdata(dev);
906 	const char **supplicants = (const char **)ext->supplied_to;
907 	struct ab8500_btemp *di;
908 	union power_supply_propval ret;
909 	int j;
910 
911 	psy = (struct power_supply *)data;
912 	di = power_supply_get_drvdata(psy);
913 
914 	/*
915 	 * For all psy where the name of your driver
916 	 * appears in any supplied_to
917 	 */
918 	j = match_string(supplicants, ext->num_supplicants, psy->desc->name);
919 	if (j < 0)
920 		return 0;
921 
922 	/* Go through all properties for the psy */
923 	for (j = 0; j < ext->desc->num_properties; j++) {
924 		enum power_supply_property prop;
925 		prop = ext->desc->properties[j];
926 
927 		if (power_supply_get_property(ext, prop, &ret))
928 			continue;
929 
930 		switch (prop) {
931 		case POWER_SUPPLY_PROP_PRESENT:
932 			switch (ext->desc->type) {
933 			case POWER_SUPPLY_TYPE_MAINS:
934 				/* AC disconnected */
935 				if (!ret.intval && di->events.ac_conn) {
936 					di->events.ac_conn = false;
937 				}
938 				/* AC connected */
939 				else if (ret.intval && !di->events.ac_conn) {
940 					di->events.ac_conn = true;
941 					if (!di->events.usb_conn)
942 						ab8500_btemp_periodic(di, true);
943 				}
944 				break;
945 			case POWER_SUPPLY_TYPE_USB:
946 				/* USB disconnected */
947 				if (!ret.intval && di->events.usb_conn) {
948 					di->events.usb_conn = false;
949 				}
950 				/* USB connected */
951 				else if (ret.intval && !di->events.usb_conn) {
952 					di->events.usb_conn = true;
953 					if (!di->events.ac_conn)
954 						ab8500_btemp_periodic(di, true);
955 				}
956 				break;
957 			default:
958 				break;
959 			}
960 			break;
961 		default:
962 			break;
963 		}
964 	}
965 	return 0;
966 }
967 
968 /**
969  * ab8500_btemp_external_power_changed() - callback for power supply changes
970  * @psy:       pointer to the structure power_supply
971  *
972  * This function is pointing to the function pointer external_power_changed
973  * of the structure power_supply.
974  * This function gets executed when there is a change in the external power
975  * supply to the btemp.
976  */
977 static void ab8500_btemp_external_power_changed(struct power_supply *psy)
978 {
979 	struct ab8500_btemp *di = power_supply_get_drvdata(psy);
980 
981 	class_for_each_device(power_supply_class, NULL,
982 		di->btemp_psy, ab8500_btemp_get_ext_psy_data);
983 }
984 
985 /* ab8500 btemp driver interrupts and their respective isr */
986 static struct ab8500_btemp_interrupts ab8500_btemp_irq[] = {
987 	{"BAT_CTRL_INDB", ab8500_btemp_batctrlindb_handler},
988 	{"BTEMP_LOW", ab8500_btemp_templow_handler},
989 	{"BTEMP_HIGH", ab8500_btemp_temphigh_handler},
990 	{"BTEMP_LOW_MEDIUM", ab8500_btemp_lowmed_handler},
991 	{"BTEMP_MEDIUM_HIGH", ab8500_btemp_medhigh_handler},
992 };
993 
994 #if defined(CONFIG_PM)
995 static int ab8500_btemp_resume(struct platform_device *pdev)
996 {
997 	struct ab8500_btemp *di = platform_get_drvdata(pdev);
998 
999 	ab8500_btemp_periodic(di, true);
1000 
1001 	return 0;
1002 }
1003 
1004 static int ab8500_btemp_suspend(struct platform_device *pdev,
1005 	pm_message_t state)
1006 {
1007 	struct ab8500_btemp *di = platform_get_drvdata(pdev);
1008 
1009 	ab8500_btemp_periodic(di, false);
1010 
1011 	return 0;
1012 }
1013 #else
1014 #define ab8500_btemp_suspend      NULL
1015 #define ab8500_btemp_resume       NULL
1016 #endif
1017 
1018 static int ab8500_btemp_remove(struct platform_device *pdev)
1019 {
1020 	struct ab8500_btemp *di = platform_get_drvdata(pdev);
1021 	int i, irq;
1022 
1023 	/* Disable interrupts */
1024 	for (i = 0; i < ARRAY_SIZE(ab8500_btemp_irq); i++) {
1025 		irq = platform_get_irq_byname(pdev, ab8500_btemp_irq[i].name);
1026 		free_irq(irq, di);
1027 	}
1028 
1029 	/* Delete the work queue */
1030 	destroy_workqueue(di->btemp_wq);
1031 
1032 	flush_scheduled_work();
1033 	power_supply_unregister(di->btemp_psy);
1034 
1035 	return 0;
1036 }
1037 
1038 static char *supply_interface[] = {
1039 	"ab8500_chargalg",
1040 	"ab8500_fg",
1041 };
1042 
1043 static const struct power_supply_desc ab8500_btemp_desc = {
1044 	.name			= "ab8500_btemp",
1045 	.type			= POWER_SUPPLY_TYPE_BATTERY,
1046 	.properties		= ab8500_btemp_props,
1047 	.num_properties		= ARRAY_SIZE(ab8500_btemp_props),
1048 	.get_property		= ab8500_btemp_get_property,
1049 	.external_power_changed	= ab8500_btemp_external_power_changed,
1050 };
1051 
1052 static int ab8500_btemp_probe(struct platform_device *pdev)
1053 {
1054 	struct device_node *np = pdev->dev.of_node;
1055 	struct abx500_bm_data *plat = pdev->dev.platform_data;
1056 	struct power_supply_config psy_cfg = {};
1057 	struct ab8500_btemp *di;
1058 	int irq, i, ret = 0;
1059 	u8 val;
1060 
1061 	di = devm_kzalloc(&pdev->dev, sizeof(*di), GFP_KERNEL);
1062 	if (!di) {
1063 		dev_err(&pdev->dev, "%s no mem for ab8500_btemp\n", __func__);
1064 		return -ENOMEM;
1065 	}
1066 
1067 	if (!plat) {
1068 		dev_err(&pdev->dev, "no battery management data supplied\n");
1069 		return -EINVAL;
1070 	}
1071 	di->bm = plat;
1072 
1073 	if (np) {
1074 		ret = ab8500_bm_of_probe(&pdev->dev, np, di->bm);
1075 		if (ret) {
1076 			dev_err(&pdev->dev, "failed to get battery information\n");
1077 			return ret;
1078 		}
1079 	}
1080 
1081 	/* get parent data */
1082 	di->dev = &pdev->dev;
1083 	di->parent = dev_get_drvdata(pdev->dev.parent);
1084 	di->gpadc = ab8500_gpadc_get("ab8500-gpadc.0");
1085 
1086 	di->initialized = false;
1087 
1088 	psy_cfg.supplied_to = supply_interface;
1089 	psy_cfg.num_supplicants = ARRAY_SIZE(supply_interface);
1090 	psy_cfg.drv_data = di;
1091 
1092 	/* Create a work queue for the btemp */
1093 	di->btemp_wq =
1094 		alloc_workqueue("ab8500_btemp_wq", WQ_MEM_RECLAIM, 0);
1095 	if (di->btemp_wq == NULL) {
1096 		dev_err(di->dev, "failed to create work queue\n");
1097 		return -ENOMEM;
1098 	}
1099 
1100 	/* Init work for measuring temperature periodically */
1101 	INIT_DEFERRABLE_WORK(&di->btemp_periodic_work,
1102 		ab8500_btemp_periodic_work);
1103 
1104 	/* Set BTEMP thermal limits. Low and Med are fixed */
1105 	di->btemp_ranges.btemp_low_limit = BTEMP_THERMAL_LOW_LIMIT;
1106 	di->btemp_ranges.btemp_med_limit = BTEMP_THERMAL_MED_LIMIT;
1107 
1108 	ret = abx500_get_register_interruptible(di->dev, AB8500_CHARGER,
1109 		AB8500_BTEMP_HIGH_TH, &val);
1110 	if (ret < 0) {
1111 		dev_err(di->dev, "%s ab8500 read failed\n", __func__);
1112 		goto free_btemp_wq;
1113 	}
1114 	switch (val) {
1115 	case BTEMP_HIGH_TH_57_0:
1116 	case BTEMP_HIGH_TH_57_1:
1117 		di->btemp_ranges.btemp_high_limit =
1118 			BTEMP_THERMAL_HIGH_LIMIT_57;
1119 		break;
1120 	case BTEMP_HIGH_TH_52:
1121 		di->btemp_ranges.btemp_high_limit =
1122 			BTEMP_THERMAL_HIGH_LIMIT_52;
1123 		break;
1124 	case BTEMP_HIGH_TH_62:
1125 		di->btemp_ranges.btemp_high_limit =
1126 			BTEMP_THERMAL_HIGH_LIMIT_62;
1127 		break;
1128 	}
1129 
1130 	/* Register BTEMP power supply class */
1131 	di->btemp_psy = power_supply_register(di->dev, &ab8500_btemp_desc,
1132 					      &psy_cfg);
1133 	if (IS_ERR(di->btemp_psy)) {
1134 		dev_err(di->dev, "failed to register BTEMP psy\n");
1135 		ret = PTR_ERR(di->btemp_psy);
1136 		goto free_btemp_wq;
1137 	}
1138 
1139 	/* Register interrupts */
1140 	for (i = 0; i < ARRAY_SIZE(ab8500_btemp_irq); i++) {
1141 		irq = platform_get_irq_byname(pdev, ab8500_btemp_irq[i].name);
1142 		ret = request_threaded_irq(irq, NULL, ab8500_btemp_irq[i].isr,
1143 			IRQF_SHARED | IRQF_NO_SUSPEND,
1144 			ab8500_btemp_irq[i].name, di);
1145 
1146 		if (ret) {
1147 			dev_err(di->dev, "failed to request %s IRQ %d: %d\n"
1148 				, ab8500_btemp_irq[i].name, irq, ret);
1149 			goto free_irq;
1150 		}
1151 		dev_dbg(di->dev, "Requested %s IRQ %d: %d\n",
1152 			ab8500_btemp_irq[i].name, irq, ret);
1153 	}
1154 
1155 	platform_set_drvdata(pdev, di);
1156 
1157 	/* Kick off periodic temperature measurements */
1158 	ab8500_btemp_periodic(di, true);
1159 	list_add_tail(&di->node, &ab8500_btemp_list);
1160 
1161 	return ret;
1162 
1163 free_irq:
1164 	power_supply_unregister(di->btemp_psy);
1165 
1166 	/* We also have to free all successfully registered irqs */
1167 	for (i = i - 1; i >= 0; i--) {
1168 		irq = platform_get_irq_byname(pdev, ab8500_btemp_irq[i].name);
1169 		free_irq(irq, di);
1170 	}
1171 free_btemp_wq:
1172 	destroy_workqueue(di->btemp_wq);
1173 	return ret;
1174 }
1175 
1176 static const struct of_device_id ab8500_btemp_match[] = {
1177 	{ .compatible = "stericsson,ab8500-btemp", },
1178 	{ },
1179 };
1180 
1181 static struct platform_driver ab8500_btemp_driver = {
1182 	.probe = ab8500_btemp_probe,
1183 	.remove = ab8500_btemp_remove,
1184 	.suspend = ab8500_btemp_suspend,
1185 	.resume = ab8500_btemp_resume,
1186 	.driver = {
1187 		.name = "ab8500-btemp",
1188 		.of_match_table = ab8500_btemp_match,
1189 	},
1190 };
1191 
1192 static int __init ab8500_btemp_init(void)
1193 {
1194 	return platform_driver_register(&ab8500_btemp_driver);
1195 }
1196 
1197 static void __exit ab8500_btemp_exit(void)
1198 {
1199 	platform_driver_unregister(&ab8500_btemp_driver);
1200 }
1201 
1202 device_initcall(ab8500_btemp_init);
1203 module_exit(ab8500_btemp_exit);
1204 
1205 MODULE_LICENSE("GPL v2");
1206 MODULE_AUTHOR("Johan Palsson, Karl Komierowski, Arun R Murthy");
1207 MODULE_ALIAS("platform:ab8500-btemp");
1208 MODULE_DESCRIPTION("AB8500 battery temperature driver");
1209