1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * Battery charger driver for Dialog Semiconductor DA9030
4  *
5  * Copyright (C) 2008 Compulab, Ltd.
6  * 	Mike Rapoport <mike@compulab.co.il>
7  */
8 
9 #include <linux/kernel.h>
10 #include <linux/slab.h>
11 #include <linux/init.h>
12 #include <linux/types.h>
13 #include <linux/device.h>
14 #include <linux/workqueue.h>
15 #include <linux/module.h>
16 #include <linux/platform_device.h>
17 #include <linux/power_supply.h>
18 #include <linux/mfd/da903x.h>
19 
20 #include <linux/debugfs.h>
21 #include <linux/seq_file.h>
22 #include <linux/notifier.h>
23 
24 #define DA9030_FAULT_LOG		0x0a
25 #define DA9030_FAULT_LOG_OVER_TEMP	(1 << 7)
26 #define DA9030_FAULT_LOG_VBAT_OVER	(1 << 4)
27 
28 #define DA9030_CHARGE_CONTROL		0x28
29 #define DA9030_CHRG_CHARGER_ENABLE	(1 << 7)
30 
31 #define DA9030_ADC_MAN_CONTROL		0x30
32 #define DA9030_ADC_TBATREF_ENABLE	(1 << 5)
33 #define DA9030_ADC_LDO_INT_ENABLE	(1 << 4)
34 
35 #define DA9030_ADC_AUTO_CONTROL		0x31
36 #define DA9030_ADC_TBAT_ENABLE		(1 << 5)
37 #define DA9030_ADC_VBAT_IN_TXON		(1 << 4)
38 #define DA9030_ADC_VCH_ENABLE		(1 << 3)
39 #define DA9030_ADC_ICH_ENABLE		(1 << 2)
40 #define DA9030_ADC_VBAT_ENABLE		(1 << 1)
41 #define DA9030_ADC_AUTO_SLEEP_ENABLE	(1 << 0)
42 
43 #define DA9030_VBATMON		0x32
44 #define DA9030_VBATMONTXON	0x33
45 #define DA9030_TBATHIGHP	0x34
46 #define DA9030_TBATHIGHN	0x35
47 #define DA9030_TBATLOW		0x36
48 
49 #define DA9030_VBAT_RES		0x41
50 #define DA9030_VBATMIN_RES	0x42
51 #define DA9030_VBATMINTXON_RES	0x43
52 #define DA9030_ICHMAX_RES	0x44
53 #define DA9030_ICHMIN_RES	0x45
54 #define DA9030_ICHAVERAGE_RES	0x46
55 #define DA9030_VCHMAX_RES	0x47
56 #define DA9030_VCHMIN_RES	0x48
57 #define DA9030_TBAT_RES		0x49
58 
59 struct da9030_adc_res {
60 	uint8_t vbat_res;
61 	uint8_t vbatmin_res;
62 	uint8_t vbatmintxon;
63 	uint8_t ichmax_res;
64 	uint8_t ichmin_res;
65 	uint8_t ichaverage_res;
66 	uint8_t vchmax_res;
67 	uint8_t vchmin_res;
68 	uint8_t tbat_res;
69 	uint8_t adc_in4_res;
70 	uint8_t adc_in5_res;
71 };
72 
73 struct da9030_battery_thresholds {
74 	int tbat_low;
75 	int tbat_high;
76 	int tbat_restart;
77 
78 	int vbat_low;
79 	int vbat_crit;
80 	int vbat_charge_start;
81 	int vbat_charge_stop;
82 	int vbat_charge_restart;
83 
84 	int vcharge_min;
85 	int vcharge_max;
86 };
87 
88 struct da9030_charger {
89 	struct power_supply *psy;
90 	struct power_supply_desc psy_desc;
91 
92 	struct device *master;
93 
94 	struct da9030_adc_res adc;
95 	struct delayed_work work;
96 	unsigned int interval;
97 
98 	struct power_supply_info *battery_info;
99 
100 	struct da9030_battery_thresholds thresholds;
101 
102 	unsigned int charge_milliamp;
103 	unsigned int charge_millivolt;
104 
105 	/* charger status */
106 	bool chdet;
107 	uint8_t fault;
108 	int mA;
109 	int mV;
110 	bool is_on;
111 
112 	struct notifier_block nb;
113 
114 	/* platform callbacks for battery low and critical events */
115 	void (*battery_low)(void);
116 	void (*battery_critical)(void);
117 
118 	struct dentry *debug_file;
119 };
120 
121 static inline int da9030_reg_to_mV(int reg)
122 {
123 	return ((reg * 2650) >> 8) + 2650;
124 }
125 
126 static inline int da9030_millivolt_to_reg(int mV)
127 {
128 	return ((mV - 2650) << 8) / 2650;
129 }
130 
131 static inline int da9030_reg_to_mA(int reg)
132 {
133 	return ((reg * 24000) >> 8) / 15;
134 }
135 
136 #ifdef CONFIG_DEBUG_FS
137 static int bat_debug_show(struct seq_file *s, void *data)
138 {
139 	struct da9030_charger *charger = s->private;
140 
141 	seq_printf(s, "charger is %s\n", charger->is_on ? "on" : "off");
142 	if (charger->chdet) {
143 		seq_printf(s, "iset = %dmA, vset = %dmV\n",
144 			   charger->mA, charger->mV);
145 	}
146 
147 	seq_printf(s, "vbat_res = %d (%dmV)\n",
148 		   charger->adc.vbat_res,
149 		   da9030_reg_to_mV(charger->adc.vbat_res));
150 	seq_printf(s, "vbatmin_res = %d (%dmV)\n",
151 		   charger->adc.vbatmin_res,
152 		   da9030_reg_to_mV(charger->adc.vbatmin_res));
153 	seq_printf(s, "vbatmintxon = %d (%dmV)\n",
154 		   charger->adc.vbatmintxon,
155 		   da9030_reg_to_mV(charger->adc.vbatmintxon));
156 	seq_printf(s, "ichmax_res = %d (%dmA)\n",
157 		   charger->adc.ichmax_res,
158 		   da9030_reg_to_mV(charger->adc.ichmax_res));
159 	seq_printf(s, "ichmin_res = %d (%dmA)\n",
160 		   charger->adc.ichmin_res,
161 		   da9030_reg_to_mA(charger->adc.ichmin_res));
162 	seq_printf(s, "ichaverage_res = %d (%dmA)\n",
163 		   charger->adc.ichaverage_res,
164 		   da9030_reg_to_mA(charger->adc.ichaverage_res));
165 	seq_printf(s, "vchmax_res = %d (%dmV)\n",
166 		   charger->adc.vchmax_res,
167 		   da9030_reg_to_mA(charger->adc.vchmax_res));
168 	seq_printf(s, "vchmin_res = %d (%dmV)\n",
169 		   charger->adc.vchmin_res,
170 		   da9030_reg_to_mV(charger->adc.vchmin_res));
171 
172 	return 0;
173 }
174 
175 static int debug_open(struct inode *inode, struct file *file)
176 {
177 	return single_open(file, bat_debug_show, inode->i_private);
178 }
179 
180 static const struct file_operations bat_debug_fops = {
181 	.open		= debug_open,
182 	.read		= seq_read,
183 	.llseek		= seq_lseek,
184 	.release	= single_release,
185 };
186 
187 static struct dentry *da9030_bat_create_debugfs(struct da9030_charger *charger)
188 {
189 	charger->debug_file = debugfs_create_file("charger", 0666, NULL,
190 						  charger, &bat_debug_fops);
191 	return charger->debug_file;
192 }
193 
194 static void da9030_bat_remove_debugfs(struct da9030_charger *charger)
195 {
196 	debugfs_remove(charger->debug_file);
197 }
198 #else
199 static inline struct dentry *da9030_bat_create_debugfs(struct da9030_charger *charger)
200 {
201 	return NULL;
202 }
203 static inline void da9030_bat_remove_debugfs(struct da9030_charger *charger)
204 {
205 }
206 #endif
207 
208 static inline void da9030_read_adc(struct da9030_charger *charger,
209 				   struct da9030_adc_res *adc)
210 {
211 	da903x_reads(charger->master, DA9030_VBAT_RES,
212 		     sizeof(*adc), (uint8_t *)adc);
213 }
214 
215 static void da9030_charger_update_state(struct da9030_charger *charger)
216 {
217 	uint8_t val;
218 
219 	da903x_read(charger->master, DA9030_CHARGE_CONTROL, &val);
220 	charger->is_on = (val & DA9030_CHRG_CHARGER_ENABLE) ? 1 : 0;
221 	charger->mA = ((val >> 3) & 0xf) * 100;
222 	charger->mV = (val & 0x7) * 50 + 4000;
223 
224 	da9030_read_adc(charger, &charger->adc);
225 	da903x_read(charger->master, DA9030_FAULT_LOG, &charger->fault);
226 	charger->chdet = da903x_query_status(charger->master,
227 						     DA9030_STATUS_CHDET);
228 }
229 
230 static void da9030_set_charge(struct da9030_charger *charger, int on)
231 {
232 	uint8_t val;
233 
234 	if (on) {
235 		val = DA9030_CHRG_CHARGER_ENABLE;
236 		val |= (charger->charge_milliamp / 100) << 3;
237 		val |= (charger->charge_millivolt - 4000) / 50;
238 		charger->is_on = 1;
239 	} else {
240 		val = 0;
241 		charger->is_on = 0;
242 	}
243 
244 	da903x_write(charger->master, DA9030_CHARGE_CONTROL, val);
245 
246 	power_supply_changed(charger->psy);
247 }
248 
249 static void da9030_charger_check_state(struct da9030_charger *charger)
250 {
251 	da9030_charger_update_state(charger);
252 
253 	/* we wake or boot with external power on */
254 	if (!charger->is_on) {
255 		if ((charger->chdet) &&
256 		    (charger->adc.vbat_res <
257 		     charger->thresholds.vbat_charge_start)) {
258 			da9030_set_charge(charger, 1);
259 		}
260 	} else {
261 		/* Charger has been pulled out */
262 		if (!charger->chdet) {
263 			da9030_set_charge(charger, 0);
264 			return;
265 		}
266 
267 		if (charger->adc.vbat_res >=
268 		    charger->thresholds.vbat_charge_stop) {
269 			da9030_set_charge(charger, 0);
270 			da903x_write(charger->master, DA9030_VBATMON,
271 				       charger->thresholds.vbat_charge_restart);
272 		} else if (charger->adc.vbat_res >
273 			   charger->thresholds.vbat_low) {
274 			/* we are charging and passed LOW_THRESH,
275 			   so upate DA9030 VBAT threshold
276 			 */
277 			da903x_write(charger->master, DA9030_VBATMON,
278 				     charger->thresholds.vbat_low);
279 		}
280 		if (charger->adc.vchmax_res > charger->thresholds.vcharge_max ||
281 		    charger->adc.vchmin_res < charger->thresholds.vcharge_min ||
282 		    /* Tempreture readings are negative */
283 		    charger->adc.tbat_res < charger->thresholds.tbat_high ||
284 		    charger->adc.tbat_res > charger->thresholds.tbat_low) {
285 			/* disable charger */
286 			da9030_set_charge(charger, 0);
287 		}
288 	}
289 }
290 
291 static void da9030_charging_monitor(struct work_struct *work)
292 {
293 	struct da9030_charger *charger;
294 
295 	charger = container_of(work, struct da9030_charger, work.work);
296 
297 	da9030_charger_check_state(charger);
298 
299 	/* reschedule for the next time */
300 	schedule_delayed_work(&charger->work, charger->interval);
301 }
302 
303 static enum power_supply_property da9030_battery_props[] = {
304 	POWER_SUPPLY_PROP_MODEL_NAME,
305 	POWER_SUPPLY_PROP_STATUS,
306 	POWER_SUPPLY_PROP_HEALTH,
307 	POWER_SUPPLY_PROP_TECHNOLOGY,
308 	POWER_SUPPLY_PROP_VOLTAGE_MAX_DESIGN,
309 	POWER_SUPPLY_PROP_VOLTAGE_MIN_DESIGN,
310 	POWER_SUPPLY_PROP_VOLTAGE_NOW,
311 	POWER_SUPPLY_PROP_CURRENT_AVG,
312 };
313 
314 static void da9030_battery_check_status(struct da9030_charger *charger,
315 				    union power_supply_propval *val)
316 {
317 	if (charger->chdet) {
318 		if (charger->is_on)
319 			val->intval = POWER_SUPPLY_STATUS_CHARGING;
320 		else
321 			val->intval = POWER_SUPPLY_STATUS_NOT_CHARGING;
322 	} else {
323 		val->intval = POWER_SUPPLY_STATUS_DISCHARGING;
324 	}
325 }
326 
327 static void da9030_battery_check_health(struct da9030_charger *charger,
328 				    union power_supply_propval *val)
329 {
330 	if (charger->fault & DA9030_FAULT_LOG_OVER_TEMP)
331 		val->intval = POWER_SUPPLY_HEALTH_OVERHEAT;
332 	else if (charger->fault & DA9030_FAULT_LOG_VBAT_OVER)
333 		val->intval = POWER_SUPPLY_HEALTH_OVERVOLTAGE;
334 	else
335 		val->intval = POWER_SUPPLY_HEALTH_GOOD;
336 }
337 
338 static int da9030_battery_get_property(struct power_supply *psy,
339 				   enum power_supply_property psp,
340 				   union power_supply_propval *val)
341 {
342 	struct da9030_charger *charger = power_supply_get_drvdata(psy);
343 
344 	switch (psp) {
345 	case POWER_SUPPLY_PROP_STATUS:
346 		da9030_battery_check_status(charger, val);
347 		break;
348 	case POWER_SUPPLY_PROP_HEALTH:
349 		da9030_battery_check_health(charger, val);
350 		break;
351 	case POWER_SUPPLY_PROP_TECHNOLOGY:
352 		val->intval = charger->battery_info->technology;
353 		break;
354 	case POWER_SUPPLY_PROP_VOLTAGE_MAX_DESIGN:
355 		val->intval = charger->battery_info->voltage_max_design;
356 		break;
357 	case POWER_SUPPLY_PROP_VOLTAGE_MIN_DESIGN:
358 		val->intval = charger->battery_info->voltage_min_design;
359 		break;
360 	case POWER_SUPPLY_PROP_VOLTAGE_NOW:
361 		val->intval = da9030_reg_to_mV(charger->adc.vbat_res) * 1000;
362 		break;
363 	case POWER_SUPPLY_PROP_CURRENT_AVG:
364 		val->intval =
365 			da9030_reg_to_mA(charger->adc.ichaverage_res) * 1000;
366 		break;
367 	case POWER_SUPPLY_PROP_MODEL_NAME:
368 		val->strval = charger->battery_info->name;
369 		break;
370 	default:
371 		break;
372 	}
373 
374 	return 0;
375 }
376 
377 static void da9030_battery_vbat_event(struct da9030_charger *charger)
378 {
379 	da9030_read_adc(charger, &charger->adc);
380 
381 	if (charger->is_on)
382 		return;
383 
384 	if (charger->adc.vbat_res < charger->thresholds.vbat_low) {
385 		/* set VBAT threshold for critical */
386 		da903x_write(charger->master, DA9030_VBATMON,
387 			     charger->thresholds.vbat_crit);
388 		if (charger->battery_low)
389 			charger->battery_low();
390 	} else if (charger->adc.vbat_res <
391 		   charger->thresholds.vbat_crit) {
392 		/* notify the system of battery critical */
393 		if (charger->battery_critical)
394 			charger->battery_critical();
395 	}
396 }
397 
398 static int da9030_battery_event(struct notifier_block *nb, unsigned long event,
399 				void *data)
400 {
401 	struct da9030_charger *charger =
402 		container_of(nb, struct da9030_charger, nb);
403 
404 	switch (event) {
405 	case DA9030_EVENT_CHDET:
406 		cancel_delayed_work_sync(&charger->work);
407 		schedule_work(&charger->work.work);
408 		break;
409 	case DA9030_EVENT_VBATMON:
410 		da9030_battery_vbat_event(charger);
411 		break;
412 	case DA9030_EVENT_CHIOVER:
413 	case DA9030_EVENT_TBAT:
414 		da9030_set_charge(charger, 0);
415 		break;
416 	}
417 
418 	return 0;
419 }
420 
421 static void da9030_battery_convert_thresholds(struct da9030_charger *charger,
422 					      struct da9030_battery_info *pdata)
423 {
424 	charger->thresholds.tbat_low = pdata->tbat_low;
425 	charger->thresholds.tbat_high = pdata->tbat_high;
426 	charger->thresholds.tbat_restart  = pdata->tbat_restart;
427 
428 	charger->thresholds.vbat_low =
429 		da9030_millivolt_to_reg(pdata->vbat_low);
430 	charger->thresholds.vbat_crit =
431 		da9030_millivolt_to_reg(pdata->vbat_crit);
432 	charger->thresholds.vbat_charge_start =
433 		da9030_millivolt_to_reg(pdata->vbat_charge_start);
434 	charger->thresholds.vbat_charge_stop =
435 		da9030_millivolt_to_reg(pdata->vbat_charge_stop);
436 	charger->thresholds.vbat_charge_restart =
437 		da9030_millivolt_to_reg(pdata->vbat_charge_restart);
438 
439 	charger->thresholds.vcharge_min =
440 		da9030_millivolt_to_reg(pdata->vcharge_min);
441 	charger->thresholds.vcharge_max =
442 		da9030_millivolt_to_reg(pdata->vcharge_max);
443 }
444 
445 static void da9030_battery_setup_psy(struct da9030_charger *charger)
446 {
447 	struct power_supply_desc *psy_desc = &charger->psy_desc;
448 	struct power_supply_info *info = charger->battery_info;
449 
450 	psy_desc->name = info->name;
451 	psy_desc->use_for_apm = info->use_for_apm;
452 	psy_desc->type = POWER_SUPPLY_TYPE_BATTERY;
453 	psy_desc->get_property = da9030_battery_get_property;
454 
455 	psy_desc->properties = da9030_battery_props;
456 	psy_desc->num_properties = ARRAY_SIZE(da9030_battery_props);
457 };
458 
459 static int da9030_battery_charger_init(struct da9030_charger *charger)
460 {
461 	char v[5];
462 	int ret;
463 
464 	v[0] = v[1] = charger->thresholds.vbat_low;
465 	v[2] = charger->thresholds.tbat_high;
466 	v[3] = charger->thresholds.tbat_restart;
467 	v[4] = charger->thresholds.tbat_low;
468 
469 	ret = da903x_writes(charger->master, DA9030_VBATMON, 5, v);
470 	if (ret)
471 		return ret;
472 
473 	/*
474 	 * Enable reference voltage supply for ADC from the LDO_INTERNAL
475 	 * regulator. Must be set before ADC measurements can be made.
476 	 */
477 	ret = da903x_write(charger->master, DA9030_ADC_MAN_CONTROL,
478 			   DA9030_ADC_LDO_INT_ENABLE |
479 			   DA9030_ADC_TBATREF_ENABLE);
480 	if (ret)
481 		return ret;
482 
483 	/* enable auto ADC measuremnts */
484 	return da903x_write(charger->master, DA9030_ADC_AUTO_CONTROL,
485 			    DA9030_ADC_TBAT_ENABLE | DA9030_ADC_VBAT_IN_TXON |
486 			    DA9030_ADC_VCH_ENABLE | DA9030_ADC_ICH_ENABLE |
487 			    DA9030_ADC_VBAT_ENABLE |
488 			    DA9030_ADC_AUTO_SLEEP_ENABLE);
489 }
490 
491 static int da9030_battery_probe(struct platform_device *pdev)
492 {
493 	struct da9030_charger *charger;
494 	struct power_supply_config psy_cfg = {};
495 	struct da9030_battery_info *pdata = pdev->dev.platform_data;
496 	int ret;
497 
498 	if (pdata == NULL)
499 		return -EINVAL;
500 
501 	if (pdata->charge_milliamp >= 1500 ||
502 	    pdata->charge_millivolt < 4000 ||
503 	    pdata->charge_millivolt > 4350)
504 		return -EINVAL;
505 
506 	charger = devm_kzalloc(&pdev->dev, sizeof(*charger), GFP_KERNEL);
507 	if (charger == NULL)
508 		return -ENOMEM;
509 
510 	charger->master = pdev->dev.parent;
511 
512 	/* 10 seconds between monitor runs unless platform defines other
513 	   interval */
514 	charger->interval = msecs_to_jiffies(
515 		(pdata->batmon_interval ? : 10) * 1000);
516 
517 	charger->charge_milliamp = pdata->charge_milliamp;
518 	charger->charge_millivolt = pdata->charge_millivolt;
519 	charger->battery_info = pdata->battery_info;
520 	charger->battery_low = pdata->battery_low;
521 	charger->battery_critical = pdata->battery_critical;
522 
523 	da9030_battery_convert_thresholds(charger, pdata);
524 
525 	ret = da9030_battery_charger_init(charger);
526 	if (ret)
527 		goto err_charger_init;
528 
529 	INIT_DELAYED_WORK(&charger->work, da9030_charging_monitor);
530 	schedule_delayed_work(&charger->work, charger->interval);
531 
532 	charger->nb.notifier_call = da9030_battery_event;
533 	ret = da903x_register_notifier(charger->master, &charger->nb,
534 				       DA9030_EVENT_CHDET |
535 				       DA9030_EVENT_VBATMON |
536 				       DA9030_EVENT_CHIOVER |
537 				       DA9030_EVENT_TBAT);
538 	if (ret)
539 		goto err_notifier;
540 
541 	da9030_battery_setup_psy(charger);
542 	psy_cfg.drv_data = charger;
543 	charger->psy = power_supply_register(&pdev->dev, &charger->psy_desc,
544 					     &psy_cfg);
545 	if (IS_ERR(charger->psy)) {
546 		ret = PTR_ERR(charger->psy);
547 		goto err_ps_register;
548 	}
549 
550 	charger->debug_file = da9030_bat_create_debugfs(charger);
551 	platform_set_drvdata(pdev, charger);
552 	return 0;
553 
554 err_ps_register:
555 	da903x_unregister_notifier(charger->master, &charger->nb,
556 				   DA9030_EVENT_CHDET | DA9030_EVENT_VBATMON |
557 				   DA9030_EVENT_CHIOVER | DA9030_EVENT_TBAT);
558 err_notifier:
559 	cancel_delayed_work(&charger->work);
560 
561 err_charger_init:
562 	return ret;
563 }
564 
565 static int da9030_battery_remove(struct platform_device *dev)
566 {
567 	struct da9030_charger *charger = platform_get_drvdata(dev);
568 
569 	da9030_bat_remove_debugfs(charger);
570 
571 	da903x_unregister_notifier(charger->master, &charger->nb,
572 				   DA9030_EVENT_CHDET | DA9030_EVENT_VBATMON |
573 				   DA9030_EVENT_CHIOVER | DA9030_EVENT_TBAT);
574 	cancel_delayed_work_sync(&charger->work);
575 	da9030_set_charge(charger, 0);
576 	power_supply_unregister(charger->psy);
577 
578 	return 0;
579 }
580 
581 static struct platform_driver da903x_battery_driver = {
582 	.driver	= {
583 		.name	= "da903x-battery",
584 	},
585 	.probe = da9030_battery_probe,
586 	.remove = da9030_battery_remove,
587 };
588 
589 module_platform_driver(da903x_battery_driver);
590 
591 MODULE_DESCRIPTION("DA9030 battery charger driver");
592 MODULE_AUTHOR("Mike Rapoport, CompuLab");
593 MODULE_LICENSE("GPL");
594