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