1/*
2 * Battery charger driver for Dialog Semiconductor DA9030
3 *
4 * Copyright (C) 2008 Compulab, Ltd.
5 * 	Mike Rapoport <mike@compulab.co.il>
6 *
7 * This program is free software; you can redistribute it and/or modify
8 * it under the terms of the GNU General Public License version 2 as
9 * published by the Free Software Foundation.
10 */
11
12#include <linux/kernel.h>
13#include <linux/slab.h>
14#include <linux/init.h>
15#include <linux/types.h>
16#include <linux/device.h>
17#include <linux/workqueue.h>
18#include <linux/module.h>
19#include <linux/platform_device.h>
20#include <linux/power_supply.h>
21#include <linux/mfd/da903x.h>
22
23#include <linux/debugfs.h>
24#include <linux/seq_file.h>
25#include <linux/notifier.h>
26
27#define DA9030_FAULT_LOG		0x0a
28#define DA9030_FAULT_LOG_OVER_TEMP	(1 << 7)
29#define DA9030_FAULT_LOG_VBAT_OVER	(1 << 4)
30
31#define DA9030_CHARGE_CONTROL		0x28
32#define DA9030_CHRG_CHARGER_ENABLE	(1 << 7)
33
34#define DA9030_ADC_MAN_CONTROL		0x30
35#define DA9030_ADC_TBATREF_ENABLE	(1 << 5)
36#define DA9030_ADC_LDO_INT_ENABLE	(1 << 4)
37
38#define DA9030_ADC_AUTO_CONTROL		0x31
39#define DA9030_ADC_TBAT_ENABLE		(1 << 5)
40#define DA9030_ADC_VBAT_IN_TXON		(1 << 4)
41#define DA9030_ADC_VCH_ENABLE		(1 << 3)
42#define DA9030_ADC_ICH_ENABLE		(1 << 2)
43#define DA9030_ADC_VBAT_ENABLE		(1 << 1)
44#define DA9030_ADC_AUTO_SLEEP_ENABLE	(1 << 0)
45
46#define DA9030_VBATMON		0x32
47#define DA9030_VBATMONTXON	0x33
48#define DA9030_TBATHIGHP	0x34
49#define DA9030_TBATHIGHN	0x35
50#define DA9030_TBATLOW		0x36
51
52#define DA9030_VBAT_RES		0x41
53#define DA9030_VBATMIN_RES	0x42
54#define DA9030_VBATMINTXON_RES	0x43
55#define DA9030_ICHMAX_RES	0x44
56#define DA9030_ICHMIN_RES	0x45
57#define DA9030_ICHAVERAGE_RES	0x46
58#define DA9030_VCHMAX_RES	0x47
59#define DA9030_VCHMIN_RES	0x48
60#define DA9030_TBAT_RES		0x49
61
62struct da9030_adc_res {
63	uint8_t vbat_res;
64	uint8_t vbatmin_res;
65	uint8_t vbatmintxon;
66	uint8_t ichmax_res;
67	uint8_t ichmin_res;
68	uint8_t ichaverage_res;
69	uint8_t vchmax_res;
70	uint8_t vchmin_res;
71	uint8_t tbat_res;
72	uint8_t adc_in4_res;
73	uint8_t adc_in5_res;
74};
75
76struct da9030_battery_thresholds {
77	int tbat_low;
78	int tbat_high;
79	int tbat_restart;
80
81	int vbat_low;
82	int vbat_crit;
83	int vbat_charge_start;
84	int vbat_charge_stop;
85	int vbat_charge_restart;
86
87	int vcharge_min;
88	int vcharge_max;
89};
90
91struct da9030_charger {
92	struct power_supply *psy;
93	struct power_supply_desc psy_desc;
94
95	struct device *master;
96
97	struct da9030_adc_res adc;
98	struct delayed_work work;
99	unsigned int interval;
100
101	struct power_supply_info *battery_info;
102
103	struct da9030_battery_thresholds thresholds;
104
105	unsigned int charge_milliamp;
106	unsigned int charge_millivolt;
107
108	/* charger status */
109	bool chdet;
110	uint8_t fault;
111	int mA;
112	int mV;
113	bool is_on;
114
115	struct notifier_block nb;
116
117	/* platform callbacks for battery low and critical events */
118	void (*battery_low)(void);
119	void (*battery_critical)(void);
120
121	struct dentry *debug_file;
122};
123
124static inline int da9030_reg_to_mV(int reg)
125{
126	return ((reg * 2650) >> 8) + 2650;
127}
128
129static inline int da9030_millivolt_to_reg(int mV)
130{
131	return ((mV - 2650) << 8) / 2650;
132}
133
134static inline int da9030_reg_to_mA(int reg)
135{
136	return ((reg * 24000) >> 8) / 15;
137}
138
139#ifdef CONFIG_DEBUG_FS
140static int bat_debug_show(struct seq_file *s, void *data)
141{
142	struct da9030_charger *charger = s->private;
143
144	seq_printf(s, "charger is %s\n", charger->is_on ? "on" : "off");
145	if (charger->chdet) {
146		seq_printf(s, "iset = %dmA, vset = %dmV\n",
147			   charger->mA, charger->mV);
148	}
149
150	seq_printf(s, "vbat_res = %d (%dmV)\n",
151		   charger->adc.vbat_res,
152		   da9030_reg_to_mV(charger->adc.vbat_res));
153	seq_printf(s, "vbatmin_res = %d (%dmV)\n",
154		   charger->adc.vbatmin_res,
155		   da9030_reg_to_mV(charger->adc.vbatmin_res));
156	seq_printf(s, "vbatmintxon = %d (%dmV)\n",
157		   charger->adc.vbatmintxon,
158		   da9030_reg_to_mV(charger->adc.vbatmintxon));
159	seq_printf(s, "ichmax_res = %d (%dmA)\n",
160		   charger->adc.ichmax_res,
161		   da9030_reg_to_mV(charger->adc.ichmax_res));
162	seq_printf(s, "ichmin_res = %d (%dmA)\n",
163		   charger->adc.ichmin_res,
164		   da9030_reg_to_mA(charger->adc.ichmin_res));
165	seq_printf(s, "ichaverage_res = %d (%dmA)\n",
166		   charger->adc.ichaverage_res,
167		   da9030_reg_to_mA(charger->adc.ichaverage_res));
168	seq_printf(s, "vchmax_res = %d (%dmV)\n",
169		   charger->adc.vchmax_res,
170		   da9030_reg_to_mA(charger->adc.vchmax_res));
171	seq_printf(s, "vchmin_res = %d (%dmV)\n",
172		   charger->adc.vchmin_res,
173		   da9030_reg_to_mV(charger->adc.vchmin_res));
174
175	return 0;
176}
177
178static int debug_open(struct inode *inode, struct file *file)
179{
180	return single_open(file, bat_debug_show, inode->i_private);
181}
182
183static const struct file_operations bat_debug_fops = {
184	.open		= debug_open,
185	.read		= seq_read,
186	.llseek		= seq_lseek,
187	.release	= single_release,
188};
189
190static struct dentry *da9030_bat_create_debugfs(struct da9030_charger *charger)
191{
192	charger->debug_file = debugfs_create_file("charger", 0666, NULL,
193						  charger, &bat_debug_fops);
194	return charger->debug_file;
195}
196
197static void da9030_bat_remove_debugfs(struct da9030_charger *charger)
198{
199	debugfs_remove(charger->debug_file);
200}
201#else
202static inline struct dentry *da9030_bat_create_debugfs(struct da9030_charger *charger)
203{
204	return NULL;
205}
206static inline void da9030_bat_remove_debugfs(struct da9030_charger *charger)
207{
208}
209#endif
210
211static inline void da9030_read_adc(struct da9030_charger *charger,
212				   struct da9030_adc_res *adc)
213{
214	da903x_reads(charger->master, DA9030_VBAT_RES,
215		     sizeof(*adc), (uint8_t *)adc);
216}
217
218static void da9030_charger_update_state(struct da9030_charger *charger)
219{
220	uint8_t val;
221
222	da903x_read(charger->master, DA9030_CHARGE_CONTROL, &val);
223	charger->is_on = (val & DA9030_CHRG_CHARGER_ENABLE) ? 1 : 0;
224	charger->mA = ((val >> 3) & 0xf) * 100;
225	charger->mV = (val & 0x7) * 50 + 4000;
226
227	da9030_read_adc(charger, &charger->adc);
228	da903x_read(charger->master, DA9030_FAULT_LOG, &charger->fault);
229	charger->chdet = da903x_query_status(charger->master,
230						     DA9030_STATUS_CHDET);
231}
232
233static void da9030_set_charge(struct da9030_charger *charger, int on)
234{
235	uint8_t val;
236
237	if (on) {
238		val = DA9030_CHRG_CHARGER_ENABLE;
239		val |= (charger->charge_milliamp / 100) << 3;
240		val |= (charger->charge_millivolt - 4000) / 50;
241		charger->is_on = 1;
242	} else {
243		val = 0;
244		charger->is_on = 0;
245	}
246
247	da903x_write(charger->master, DA9030_CHARGE_CONTROL, val);
248
249	power_supply_changed(charger->psy);
250}
251
252static void da9030_charger_check_state(struct da9030_charger *charger)
253{
254	da9030_charger_update_state(charger);
255
256	/* we wake or boot with external power on */
257	if (!charger->is_on) {
258		if ((charger->chdet) &&
259		    (charger->adc.vbat_res <
260		     charger->thresholds.vbat_charge_start)) {
261			da9030_set_charge(charger, 1);
262		}
263	} else {
264		/* Charger has been pulled out */
265		if (!charger->chdet) {
266			da9030_set_charge(charger, 0);
267			return;
268		}
269
270		if (charger->adc.vbat_res >=
271		    charger->thresholds.vbat_charge_stop) {
272			da9030_set_charge(charger, 0);
273			da903x_write(charger->master, DA9030_VBATMON,
274				       charger->thresholds.vbat_charge_restart);
275		} else if (charger->adc.vbat_res >
276			   charger->thresholds.vbat_low) {
277			/* we are charging and passed LOW_THRESH,
278			   so upate DA9030 VBAT threshold
279			 */
280			da903x_write(charger->master, DA9030_VBATMON,
281				     charger->thresholds.vbat_low);
282		}
283		if (charger->adc.vchmax_res > charger->thresholds.vcharge_max ||
284		    charger->adc.vchmin_res < charger->thresholds.vcharge_min ||
285		    /* Tempreture readings are negative */
286		    charger->adc.tbat_res < charger->thresholds.tbat_high ||
287		    charger->adc.tbat_res > charger->thresholds.tbat_low) {
288			/* disable charger */
289			da9030_set_charge(charger, 0);
290		}
291	}
292}
293
294static void da9030_charging_monitor(struct work_struct *work)
295{
296	struct da9030_charger *charger;
297
298	charger = container_of(work, struct da9030_charger, work.work);
299
300	da9030_charger_check_state(charger);
301
302	/* reschedule for the next time */
303	schedule_delayed_work(&charger->work, charger->interval);
304}
305
306static enum power_supply_property da9030_battery_props[] = {
307	POWER_SUPPLY_PROP_MODEL_NAME,
308	POWER_SUPPLY_PROP_STATUS,
309	POWER_SUPPLY_PROP_HEALTH,
310	POWER_SUPPLY_PROP_TECHNOLOGY,
311	POWER_SUPPLY_PROP_VOLTAGE_MAX_DESIGN,
312	POWER_SUPPLY_PROP_VOLTAGE_MIN_DESIGN,
313	POWER_SUPPLY_PROP_VOLTAGE_NOW,
314	POWER_SUPPLY_PROP_CURRENT_AVG,
315};
316
317static void da9030_battery_check_status(struct da9030_charger *charger,
318				    union power_supply_propval *val)
319{
320	if (charger->chdet) {
321		if (charger->is_on)
322			val->intval = POWER_SUPPLY_STATUS_CHARGING;
323		else
324			val->intval = POWER_SUPPLY_STATUS_NOT_CHARGING;
325	} else {
326		val->intval = POWER_SUPPLY_STATUS_DISCHARGING;
327	}
328}
329
330static void da9030_battery_check_health(struct da9030_charger *charger,
331				    union power_supply_propval *val)
332{
333	if (charger->fault & DA9030_FAULT_LOG_OVER_TEMP)
334		val->intval = POWER_SUPPLY_HEALTH_OVERHEAT;
335	else if (charger->fault & DA9030_FAULT_LOG_VBAT_OVER)
336		val->intval = POWER_SUPPLY_HEALTH_OVERVOLTAGE;
337	else
338		val->intval = POWER_SUPPLY_HEALTH_GOOD;
339}
340
341static int da9030_battery_get_property(struct power_supply *psy,
342				   enum power_supply_property psp,
343				   union power_supply_propval *val)
344{
345	struct da9030_charger *charger = power_supply_get_drvdata(psy);
346
347	switch (psp) {
348	case POWER_SUPPLY_PROP_STATUS:
349		da9030_battery_check_status(charger, val);
350		break;
351	case POWER_SUPPLY_PROP_HEALTH:
352		da9030_battery_check_health(charger, val);
353		break;
354	case POWER_SUPPLY_PROP_TECHNOLOGY:
355		val->intval = charger->battery_info->technology;
356		break;
357	case POWER_SUPPLY_PROP_VOLTAGE_MAX_DESIGN:
358		val->intval = charger->battery_info->voltage_max_design;
359		break;
360	case POWER_SUPPLY_PROP_VOLTAGE_MIN_DESIGN:
361		val->intval = charger->battery_info->voltage_min_design;
362		break;
363	case POWER_SUPPLY_PROP_VOLTAGE_NOW:
364		val->intval = da9030_reg_to_mV(charger->adc.vbat_res) * 1000;
365		break;
366	case POWER_SUPPLY_PROP_CURRENT_AVG:
367		val->intval =
368			da9030_reg_to_mA(charger->adc.ichaverage_res) * 1000;
369		break;
370	case POWER_SUPPLY_PROP_MODEL_NAME:
371		val->strval = charger->battery_info->name;
372		break;
373	default:
374		break;
375	}
376
377	return 0;
378}
379
380static void da9030_battery_vbat_event(struct da9030_charger *charger)
381{
382	da9030_read_adc(charger, &charger->adc);
383
384	if (charger->is_on)
385		return;
386
387	if (charger->adc.vbat_res < charger->thresholds.vbat_low) {
388		/* set VBAT threshold for critical */
389		da903x_write(charger->master, DA9030_VBATMON,
390			     charger->thresholds.vbat_crit);
391		if (charger->battery_low)
392			charger->battery_low();
393	} else if (charger->adc.vbat_res <
394		   charger->thresholds.vbat_crit) {
395		/* notify the system of battery critical */
396		if (charger->battery_critical)
397			charger->battery_critical();
398	}
399}
400
401static int da9030_battery_event(struct notifier_block *nb, unsigned long event,
402				void *data)
403{
404	struct da9030_charger *charger =
405		container_of(nb, struct da9030_charger, nb);
406
407	switch (event) {
408	case DA9030_EVENT_CHDET:
409		cancel_delayed_work_sync(&charger->work);
410		schedule_work(&charger->work.work);
411		break;
412	case DA9030_EVENT_VBATMON:
413		da9030_battery_vbat_event(charger);
414		break;
415	case DA9030_EVENT_CHIOVER:
416	case DA9030_EVENT_TBAT:
417		da9030_set_charge(charger, 0);
418		break;
419	}
420
421	return 0;
422}
423
424static void da9030_battery_convert_thresholds(struct da9030_charger *charger,
425					      struct da9030_battery_info *pdata)
426{
427	charger->thresholds.tbat_low = pdata->tbat_low;
428	charger->thresholds.tbat_high = pdata->tbat_high;
429	charger->thresholds.tbat_restart  = pdata->tbat_restart;
430
431	charger->thresholds.vbat_low =
432		da9030_millivolt_to_reg(pdata->vbat_low);
433	charger->thresholds.vbat_crit =
434		da9030_millivolt_to_reg(pdata->vbat_crit);
435	charger->thresholds.vbat_charge_start =
436		da9030_millivolt_to_reg(pdata->vbat_charge_start);
437	charger->thresholds.vbat_charge_stop =
438		da9030_millivolt_to_reg(pdata->vbat_charge_stop);
439	charger->thresholds.vbat_charge_restart =
440		da9030_millivolt_to_reg(pdata->vbat_charge_restart);
441
442	charger->thresholds.vcharge_min =
443		da9030_millivolt_to_reg(pdata->vcharge_min);
444	charger->thresholds.vcharge_max =
445		da9030_millivolt_to_reg(pdata->vcharge_max);
446}
447
448static void da9030_battery_setup_psy(struct da9030_charger *charger)
449{
450	struct power_supply_desc *psy_desc = &charger->psy_desc;
451	struct power_supply_info *info = charger->battery_info;
452
453	psy_desc->name = info->name;
454	psy_desc->use_for_apm = info->use_for_apm;
455	psy_desc->type = POWER_SUPPLY_TYPE_BATTERY;
456	psy_desc->get_property = da9030_battery_get_property;
457
458	psy_desc->properties = da9030_battery_props;
459	psy_desc->num_properties = ARRAY_SIZE(da9030_battery_props);
460};
461
462static int da9030_battery_charger_init(struct da9030_charger *charger)
463{
464	char v[5];
465	int ret;
466
467	v[0] = v[1] = charger->thresholds.vbat_low;
468	v[2] = charger->thresholds.tbat_high;
469	v[3] = charger->thresholds.tbat_restart;
470	v[4] = charger->thresholds.tbat_low;
471
472	ret = da903x_writes(charger->master, DA9030_VBATMON, 5, v);
473	if (ret)
474		return ret;
475
476	/*
477	 * Enable reference voltage supply for ADC from the LDO_INTERNAL
478	 * regulator. Must be set before ADC measurements can be made.
479	 */
480	ret = da903x_write(charger->master, DA9030_ADC_MAN_CONTROL,
481			   DA9030_ADC_LDO_INT_ENABLE |
482			   DA9030_ADC_TBATREF_ENABLE);
483	if (ret)
484		return ret;
485
486	/* enable auto ADC measuremnts */
487	return da903x_write(charger->master, DA9030_ADC_AUTO_CONTROL,
488			    DA9030_ADC_TBAT_ENABLE | DA9030_ADC_VBAT_IN_TXON |
489			    DA9030_ADC_VCH_ENABLE | DA9030_ADC_ICH_ENABLE |
490			    DA9030_ADC_VBAT_ENABLE |
491			    DA9030_ADC_AUTO_SLEEP_ENABLE);
492}
493
494static int da9030_battery_probe(struct platform_device *pdev)
495{
496	struct da9030_charger *charger;
497	struct power_supply_config psy_cfg = {};
498	struct da9030_battery_info *pdata = pdev->dev.platform_data;
499	int ret;
500
501	if (pdata == NULL)
502		return -EINVAL;
503
504	if (pdata->charge_milliamp >= 1500 ||
505	    pdata->charge_millivolt < 4000 ||
506	    pdata->charge_millivolt > 4350)
507		return -EINVAL;
508
509	charger = devm_kzalloc(&pdev->dev, sizeof(*charger), GFP_KERNEL);
510	if (charger == NULL)
511		return -ENOMEM;
512
513	charger->master = pdev->dev.parent;
514
515	/* 10 seconds between monitor runs unless platform defines other
516	   interval */
517	charger->interval = msecs_to_jiffies(
518		(pdata->batmon_interval ? : 10) * 1000);
519
520	charger->charge_milliamp = pdata->charge_milliamp;
521	charger->charge_millivolt = pdata->charge_millivolt;
522	charger->battery_info = pdata->battery_info;
523	charger->battery_low = pdata->battery_low;
524	charger->battery_critical = pdata->battery_critical;
525
526	da9030_battery_convert_thresholds(charger, pdata);
527
528	ret = da9030_battery_charger_init(charger);
529	if (ret)
530		goto err_charger_init;
531
532	INIT_DELAYED_WORK(&charger->work, da9030_charging_monitor);
533	schedule_delayed_work(&charger->work, charger->interval);
534
535	charger->nb.notifier_call = da9030_battery_event;
536	ret = da903x_register_notifier(charger->master, &charger->nb,
537				       DA9030_EVENT_CHDET |
538				       DA9030_EVENT_VBATMON |
539				       DA9030_EVENT_CHIOVER |
540				       DA9030_EVENT_TBAT);
541	if (ret)
542		goto err_notifier;
543
544	da9030_battery_setup_psy(charger);
545	psy_cfg.drv_data = charger;
546	charger->psy = power_supply_register(&pdev->dev, &charger->psy_desc,
547					     &psy_cfg);
548	if (IS_ERR(charger->psy)) {
549		ret = PTR_ERR(charger->psy);
550		goto err_ps_register;
551	}
552
553	charger->debug_file = da9030_bat_create_debugfs(charger);
554	platform_set_drvdata(pdev, charger);
555	return 0;
556
557err_ps_register:
558	da903x_unregister_notifier(charger->master, &charger->nb,
559				   DA9030_EVENT_CHDET | DA9030_EVENT_VBATMON |
560				   DA9030_EVENT_CHIOVER | DA9030_EVENT_TBAT);
561err_notifier:
562	cancel_delayed_work(&charger->work);
563
564err_charger_init:
565	return ret;
566}
567
568static int da9030_battery_remove(struct platform_device *dev)
569{
570	struct da9030_charger *charger = platform_get_drvdata(dev);
571
572	da9030_bat_remove_debugfs(charger);
573
574	da903x_unregister_notifier(charger->master, &charger->nb,
575				   DA9030_EVENT_CHDET | DA9030_EVENT_VBATMON |
576				   DA9030_EVENT_CHIOVER | DA9030_EVENT_TBAT);
577	cancel_delayed_work_sync(&charger->work);
578	da9030_set_charge(charger, 0);
579	power_supply_unregister(charger->psy);
580
581	return 0;
582}
583
584static struct platform_driver da903x_battery_driver = {
585	.driver	= {
586		.name	= "da903x-battery",
587	},
588	.probe = da9030_battery_probe,
589	.remove = da9030_battery_remove,
590};
591
592module_platform_driver(da903x_battery_driver);
593
594MODULE_DESCRIPTION("DA9030 battery charger driver");
595MODULE_AUTHOR("Mike Rapoport, CompuLab");
596MODULE_LICENSE("GPL");
597