1/*
2 * Battery driver for wm8350 PMIC
3 *
4 * Copyright 2007, 2008 Wolfson Microelectronics PLC.
5 *
6 * Based on OLPC Battery Driver
7 *
8 * Copyright 2006  David Woodhouse <dwmw2@infradead.org>
9 *
10 * This program is free software; you can redistribute it and/or modify
11 * it under the terms of the GNU General Public License version 2 as
12 * published by the Free Software Foundation.
13 */
14
15#include <linux/module.h>
16#include <linux/err.h>
17#include <linux/platform_device.h>
18#include <linux/power_supply.h>
19#include <linux/mfd/wm8350/supply.h>
20#include <linux/mfd/wm8350/core.h>
21#include <linux/mfd/wm8350/comparator.h>
22
23static int wm8350_read_battery_uvolts(struct wm8350 *wm8350)
24{
25	return wm8350_read_auxadc(wm8350, WM8350_AUXADC_BATT, 0, 0)
26		* WM8350_AUX_COEFF;
27}
28
29static int wm8350_read_line_uvolts(struct wm8350 *wm8350)
30{
31	return wm8350_read_auxadc(wm8350, WM8350_AUXADC_LINE, 0, 0)
32		* WM8350_AUX_COEFF;
33}
34
35static int wm8350_read_usb_uvolts(struct wm8350 *wm8350)
36{
37	return wm8350_read_auxadc(wm8350, WM8350_AUXADC_USB, 0, 0)
38		* WM8350_AUX_COEFF;
39}
40
41#define WM8350_BATT_SUPPLY	1
42#define WM8350_USB_SUPPLY	2
43#define WM8350_LINE_SUPPLY	4
44
45static inline int wm8350_charge_time_min(struct wm8350 *wm8350, int min)
46{
47	if (!wm8350->power.rev_g_coeff)
48		return (((min - 30) / 15) & 0xf) << 8;
49	else
50		return (((min - 30) / 30) & 0xf) << 8;
51}
52
53static int wm8350_get_supplies(struct wm8350 *wm8350)
54{
55	u16 sm, ov, co, chrg;
56	int supplies = 0;
57
58	sm = wm8350_reg_read(wm8350, WM8350_STATE_MACHINE_STATUS);
59	ov = wm8350_reg_read(wm8350, WM8350_MISC_OVERRIDES);
60	co = wm8350_reg_read(wm8350, WM8350_COMPARATOR_OVERRIDES);
61	chrg = wm8350_reg_read(wm8350, WM8350_BATTERY_CHARGER_CONTROL_2);
62
63	/* USB_SM */
64	sm = (sm & WM8350_USB_SM_MASK) >> WM8350_USB_SM_SHIFT;
65
66	/* CHG_ISEL */
67	chrg &= WM8350_CHG_ISEL_MASK;
68
69	/* If the USB state machine is active then we're using that with or
70	 * without battery, otherwise check for wall supply */
71	if (((sm == WM8350_USB_SM_100_SLV) ||
72	     (sm == WM8350_USB_SM_500_SLV) ||
73	     (sm == WM8350_USB_SM_STDBY_SLV))
74	    && !(ov & WM8350_USB_LIMIT_OVRDE))
75		supplies = WM8350_USB_SUPPLY;
76	else if (((sm == WM8350_USB_SM_100_SLV) ||
77		  (sm == WM8350_USB_SM_500_SLV) ||
78		  (sm == WM8350_USB_SM_STDBY_SLV))
79		 && (ov & WM8350_USB_LIMIT_OVRDE) && (chrg == 0))
80		supplies = WM8350_USB_SUPPLY | WM8350_BATT_SUPPLY;
81	else if (co & WM8350_WALL_FB_OVRDE)
82		supplies = WM8350_LINE_SUPPLY;
83	else
84		supplies = WM8350_BATT_SUPPLY;
85
86	return supplies;
87}
88
89static int wm8350_charger_config(struct wm8350 *wm8350,
90				 struct wm8350_charger_policy *policy)
91{
92	u16 reg, eoc_mA, fast_limit_mA;
93
94	if (!policy) {
95		dev_warn(wm8350->dev,
96			 "No charger policy, charger not configured.\n");
97		return -EINVAL;
98	}
99
100	/* make sure USB fast charge current is not > 500mA */
101	if (policy->fast_limit_USB_mA > 500) {
102		dev_err(wm8350->dev, "USB fast charge > 500mA\n");
103		return -EINVAL;
104	}
105
106	eoc_mA = WM8350_CHG_EOC_mA(policy->eoc_mA);
107
108	wm8350_reg_unlock(wm8350);
109
110	reg = wm8350_reg_read(wm8350, WM8350_BATTERY_CHARGER_CONTROL_1)
111		& WM8350_CHG_ENA_R168;
112	wm8350_reg_write(wm8350, WM8350_BATTERY_CHARGER_CONTROL_1,
113			 reg | eoc_mA | policy->trickle_start_mV |
114			 WM8350_CHG_TRICKLE_TEMP_CHOKE |
115			 WM8350_CHG_TRICKLE_USB_CHOKE |
116			 WM8350_CHG_FAST_USB_THROTTLE);
117
118	if (wm8350_get_supplies(wm8350) & WM8350_USB_SUPPLY) {
119		fast_limit_mA =
120			WM8350_CHG_FAST_LIMIT_mA(policy->fast_limit_USB_mA);
121		wm8350_reg_write(wm8350, WM8350_BATTERY_CHARGER_CONTROL_2,
122			    policy->charge_mV | policy->trickle_charge_USB_mA |
123			    fast_limit_mA | wm8350_charge_time_min(wm8350,
124						policy->charge_timeout));
125
126	} else {
127		fast_limit_mA =
128			WM8350_CHG_FAST_LIMIT_mA(policy->fast_limit_mA);
129		wm8350_reg_write(wm8350, WM8350_BATTERY_CHARGER_CONTROL_2,
130			    policy->charge_mV | policy->trickle_charge_mA |
131			    fast_limit_mA | wm8350_charge_time_min(wm8350,
132						policy->charge_timeout));
133	}
134
135	wm8350_reg_lock(wm8350);
136	return 0;
137}
138
139static int wm8350_batt_status(struct wm8350 *wm8350)
140{
141	u16 state;
142
143	state = wm8350_reg_read(wm8350, WM8350_BATTERY_CHARGER_CONTROL_2);
144	state &= WM8350_CHG_STS_MASK;
145
146	switch (state) {
147	case WM8350_CHG_STS_OFF:
148		return POWER_SUPPLY_STATUS_DISCHARGING;
149
150	case WM8350_CHG_STS_TRICKLE:
151	case WM8350_CHG_STS_FAST:
152		return POWER_SUPPLY_STATUS_CHARGING;
153
154	default:
155		return POWER_SUPPLY_STATUS_UNKNOWN;
156	}
157}
158
159static ssize_t charger_state_show(struct device *dev,
160				 struct device_attribute *attr, char *buf)
161{
162	struct wm8350 *wm8350 = dev_get_drvdata(dev);
163	char *charge;
164	int state;
165
166	state = wm8350_reg_read(wm8350, WM8350_BATTERY_CHARGER_CONTROL_2) &
167	    WM8350_CHG_STS_MASK;
168	switch (state) {
169	case WM8350_CHG_STS_OFF:
170		charge = "Charger Off";
171		break;
172	case WM8350_CHG_STS_TRICKLE:
173		charge = "Trickle Charging";
174		break;
175	case WM8350_CHG_STS_FAST:
176		charge = "Fast Charging";
177		break;
178	default:
179		return 0;
180	}
181
182	return sprintf(buf, "%s\n", charge);
183}
184
185static DEVICE_ATTR(charger_state, 0444, charger_state_show, NULL);
186
187static irqreturn_t wm8350_charger_handler(int irq, void *data)
188{
189	struct wm8350 *wm8350 = data;
190	struct wm8350_power *power = &wm8350->power;
191	struct wm8350_charger_policy *policy = power->policy;
192
193	switch (irq - wm8350->irq_base) {
194	case WM8350_IRQ_CHG_BAT_FAIL:
195		dev_err(wm8350->dev, "battery failed\n");
196		break;
197	case WM8350_IRQ_CHG_TO:
198		dev_err(wm8350->dev, "charger timeout\n");
199		power_supply_changed(power->battery);
200		break;
201
202	case WM8350_IRQ_CHG_BAT_HOT:
203	case WM8350_IRQ_CHG_BAT_COLD:
204	case WM8350_IRQ_CHG_START:
205	case WM8350_IRQ_CHG_END:
206		power_supply_changed(power->battery);
207		break;
208
209	case WM8350_IRQ_CHG_FAST_RDY:
210		dev_dbg(wm8350->dev, "fast charger ready\n");
211		wm8350_charger_config(wm8350, policy);
212		wm8350_reg_unlock(wm8350);
213		wm8350_set_bits(wm8350, WM8350_BATTERY_CHARGER_CONTROL_1,
214				WM8350_CHG_FAST);
215		wm8350_reg_lock(wm8350);
216		break;
217
218	case WM8350_IRQ_CHG_VBATT_LT_3P9:
219		dev_warn(wm8350->dev, "battery < 3.9V\n");
220		break;
221	case WM8350_IRQ_CHG_VBATT_LT_3P1:
222		dev_warn(wm8350->dev, "battery < 3.1V\n");
223		break;
224	case WM8350_IRQ_CHG_VBATT_LT_2P85:
225		dev_warn(wm8350->dev, "battery < 2.85V\n");
226		break;
227
228		/* Supply change.  We will overnotify but it should do
229		 * no harm. */
230	case WM8350_IRQ_EXT_USB_FB:
231	case WM8350_IRQ_EXT_WALL_FB:
232		wm8350_charger_config(wm8350, policy);
233	case WM8350_IRQ_EXT_BAT_FB:   /* Fall through */
234		power_supply_changed(power->battery);
235		power_supply_changed(power->usb);
236		power_supply_changed(power->ac);
237		break;
238
239	default:
240		dev_err(wm8350->dev, "Unknown interrupt %d\n", irq);
241	}
242
243	return IRQ_HANDLED;
244}
245
246/*********************************************************************
247 *		AC Power
248 *********************************************************************/
249static int wm8350_ac_get_prop(struct power_supply *psy,
250			      enum power_supply_property psp,
251			      union power_supply_propval *val)
252{
253	struct wm8350 *wm8350 = dev_get_drvdata(psy->dev.parent);
254	int ret = 0;
255
256	switch (psp) {
257	case POWER_SUPPLY_PROP_ONLINE:
258		val->intval = !!(wm8350_get_supplies(wm8350) &
259				 WM8350_LINE_SUPPLY);
260		break;
261	case POWER_SUPPLY_PROP_VOLTAGE_NOW:
262		val->intval = wm8350_read_line_uvolts(wm8350);
263		break;
264	default:
265		ret = -EINVAL;
266		break;
267	}
268	return ret;
269}
270
271static enum power_supply_property wm8350_ac_props[] = {
272	POWER_SUPPLY_PROP_ONLINE,
273	POWER_SUPPLY_PROP_VOLTAGE_NOW,
274};
275
276/*********************************************************************
277 *		USB Power
278 *********************************************************************/
279static int wm8350_usb_get_prop(struct power_supply *psy,
280			       enum power_supply_property psp,
281			       union power_supply_propval *val)
282{
283	struct wm8350 *wm8350 = dev_get_drvdata(psy->dev.parent);
284	int ret = 0;
285
286	switch (psp) {
287	case POWER_SUPPLY_PROP_ONLINE:
288		val->intval = !!(wm8350_get_supplies(wm8350) &
289				 WM8350_USB_SUPPLY);
290		break;
291	case POWER_SUPPLY_PROP_VOLTAGE_NOW:
292		val->intval = wm8350_read_usb_uvolts(wm8350);
293		break;
294	default:
295		ret = -EINVAL;
296		break;
297	}
298	return ret;
299}
300
301static enum power_supply_property wm8350_usb_props[] = {
302	POWER_SUPPLY_PROP_ONLINE,
303	POWER_SUPPLY_PROP_VOLTAGE_NOW,
304};
305
306/*********************************************************************
307 *		Battery properties
308 *********************************************************************/
309
310static int wm8350_bat_check_health(struct wm8350 *wm8350)
311{
312	u16 reg;
313
314	if (wm8350_read_battery_uvolts(wm8350) < 2850000)
315		return POWER_SUPPLY_HEALTH_UNSPEC_FAILURE;
316
317	reg = wm8350_reg_read(wm8350, WM8350_CHARGER_OVERRIDES);
318	if (reg & WM8350_CHG_BATT_HOT_OVRDE)
319		return POWER_SUPPLY_HEALTH_OVERHEAT;
320
321	if (reg & WM8350_CHG_BATT_COLD_OVRDE)
322		return POWER_SUPPLY_HEALTH_COLD;
323
324	return POWER_SUPPLY_HEALTH_GOOD;
325}
326
327static int wm8350_bat_get_charge_type(struct wm8350 *wm8350)
328{
329	int state;
330
331	state = wm8350_reg_read(wm8350, WM8350_BATTERY_CHARGER_CONTROL_2) &
332	    WM8350_CHG_STS_MASK;
333	switch (state) {
334	case WM8350_CHG_STS_OFF:
335		return POWER_SUPPLY_CHARGE_TYPE_NONE;
336	case WM8350_CHG_STS_TRICKLE:
337		return POWER_SUPPLY_CHARGE_TYPE_TRICKLE;
338	case WM8350_CHG_STS_FAST:
339		return POWER_SUPPLY_CHARGE_TYPE_FAST;
340	default:
341		return POWER_SUPPLY_CHARGE_TYPE_UNKNOWN;
342	}
343}
344
345static int wm8350_bat_get_property(struct power_supply *psy,
346				   enum power_supply_property psp,
347				   union power_supply_propval *val)
348{
349	struct wm8350 *wm8350 = dev_get_drvdata(psy->dev.parent);
350	int ret = 0;
351
352	switch (psp) {
353	case POWER_SUPPLY_PROP_STATUS:
354		val->intval = wm8350_batt_status(wm8350);
355		break;
356	case POWER_SUPPLY_PROP_ONLINE:
357		val->intval = !!(wm8350_get_supplies(wm8350) &
358				 WM8350_BATT_SUPPLY);
359		break;
360	case POWER_SUPPLY_PROP_VOLTAGE_NOW:
361		val->intval = wm8350_read_battery_uvolts(wm8350);
362		break;
363	case POWER_SUPPLY_PROP_HEALTH:
364		val->intval = wm8350_bat_check_health(wm8350);
365		break;
366	case POWER_SUPPLY_PROP_CHARGE_TYPE:
367		val->intval = wm8350_bat_get_charge_type(wm8350);
368		break;
369	default:
370		ret = -EINVAL;
371		break;
372	}
373
374	return ret;
375}
376
377static enum power_supply_property wm8350_bat_props[] = {
378	POWER_SUPPLY_PROP_STATUS,
379	POWER_SUPPLY_PROP_ONLINE,
380	POWER_SUPPLY_PROP_VOLTAGE_NOW,
381	POWER_SUPPLY_PROP_HEALTH,
382	POWER_SUPPLY_PROP_CHARGE_TYPE,
383};
384
385static const struct power_supply_desc wm8350_ac_desc = {
386	.name		= "wm8350-ac",
387	.type		= POWER_SUPPLY_TYPE_MAINS,
388	.properties	= wm8350_ac_props,
389	.num_properties	= ARRAY_SIZE(wm8350_ac_props),
390	.get_property	= wm8350_ac_get_prop,
391};
392
393static const struct power_supply_desc wm8350_battery_desc = {
394	.name		= "wm8350-battery",
395	.properties	= wm8350_bat_props,
396	.num_properties	= ARRAY_SIZE(wm8350_bat_props),
397	.get_property	= wm8350_bat_get_property,
398	.use_for_apm	= 1,
399};
400
401static const struct power_supply_desc wm8350_usb_desc = {
402	.name		= "wm8350-usb",
403	.type		= POWER_SUPPLY_TYPE_USB,
404	.properties	= wm8350_usb_props,
405	.num_properties	= ARRAY_SIZE(wm8350_usb_props),
406	.get_property	= wm8350_usb_get_prop,
407};
408
409/*********************************************************************
410 *		Initialisation
411 *********************************************************************/
412
413static void wm8350_init_charger(struct wm8350 *wm8350)
414{
415	/* register our interest in charger events */
416	wm8350_register_irq(wm8350, WM8350_IRQ_CHG_BAT_HOT,
417			    wm8350_charger_handler, 0, "Battery hot", wm8350);
418	wm8350_register_irq(wm8350, WM8350_IRQ_CHG_BAT_COLD,
419			    wm8350_charger_handler, 0, "Battery cold", wm8350);
420	wm8350_register_irq(wm8350, WM8350_IRQ_CHG_BAT_FAIL,
421			    wm8350_charger_handler, 0, "Battery fail", wm8350);
422	wm8350_register_irq(wm8350, WM8350_IRQ_CHG_TO,
423			    wm8350_charger_handler, 0,
424			    "Charger timeout", wm8350);
425	wm8350_register_irq(wm8350, WM8350_IRQ_CHG_END,
426			    wm8350_charger_handler, 0,
427			    "Charge end", wm8350);
428	wm8350_register_irq(wm8350, WM8350_IRQ_CHG_START,
429			    wm8350_charger_handler, 0,
430			    "Charge start", wm8350);
431	wm8350_register_irq(wm8350, WM8350_IRQ_CHG_FAST_RDY,
432			    wm8350_charger_handler, 0,
433			    "Fast charge ready", wm8350);
434	wm8350_register_irq(wm8350, WM8350_IRQ_CHG_VBATT_LT_3P9,
435			    wm8350_charger_handler, 0,
436			    "Battery <3.9V", wm8350);
437	wm8350_register_irq(wm8350, WM8350_IRQ_CHG_VBATT_LT_3P1,
438			    wm8350_charger_handler, 0,
439			    "Battery <3.1V", wm8350);
440	wm8350_register_irq(wm8350, WM8350_IRQ_CHG_VBATT_LT_2P85,
441			    wm8350_charger_handler, 0,
442			    "Battery <2.85V", wm8350);
443
444	/* and supply change events */
445	wm8350_register_irq(wm8350, WM8350_IRQ_EXT_USB_FB,
446			    wm8350_charger_handler, 0, "USB", wm8350);
447	wm8350_register_irq(wm8350, WM8350_IRQ_EXT_WALL_FB,
448			    wm8350_charger_handler, 0, "Wall", wm8350);
449	wm8350_register_irq(wm8350, WM8350_IRQ_EXT_BAT_FB,
450			    wm8350_charger_handler, 0, "Battery", wm8350);
451}
452
453static void free_charger_irq(struct wm8350 *wm8350)
454{
455	wm8350_free_irq(wm8350, WM8350_IRQ_CHG_BAT_HOT, wm8350);
456	wm8350_free_irq(wm8350, WM8350_IRQ_CHG_BAT_COLD, wm8350);
457	wm8350_free_irq(wm8350, WM8350_IRQ_CHG_BAT_FAIL, wm8350);
458	wm8350_free_irq(wm8350, WM8350_IRQ_CHG_TO, wm8350);
459	wm8350_free_irq(wm8350, WM8350_IRQ_CHG_END, wm8350);
460	wm8350_free_irq(wm8350, WM8350_IRQ_CHG_START, wm8350);
461	wm8350_free_irq(wm8350, WM8350_IRQ_CHG_VBATT_LT_3P9, wm8350);
462	wm8350_free_irq(wm8350, WM8350_IRQ_CHG_VBATT_LT_3P1, wm8350);
463	wm8350_free_irq(wm8350, WM8350_IRQ_CHG_VBATT_LT_2P85, wm8350);
464	wm8350_free_irq(wm8350, WM8350_IRQ_EXT_USB_FB, wm8350);
465	wm8350_free_irq(wm8350, WM8350_IRQ_EXT_WALL_FB, wm8350);
466	wm8350_free_irq(wm8350, WM8350_IRQ_EXT_BAT_FB, wm8350);
467}
468
469static int wm8350_power_probe(struct platform_device *pdev)
470{
471	struct wm8350 *wm8350 = platform_get_drvdata(pdev);
472	struct wm8350_power *power = &wm8350->power;
473	struct wm8350_charger_policy *policy = power->policy;
474	int ret;
475
476	power->ac = power_supply_register(&pdev->dev, &wm8350_ac_desc, NULL);
477	if (IS_ERR(power->ac))
478		return PTR_ERR(power->ac);
479
480	power->battery = power_supply_register(&pdev->dev, &wm8350_battery_desc,
481					       NULL);
482	if (IS_ERR(power->battery)) {
483		ret = PTR_ERR(power->battery);
484		goto battery_failed;
485	}
486
487	power->usb = power_supply_register(&pdev->dev, &wm8350_usb_desc, NULL);
488	if (IS_ERR(power->usb)) {
489		ret = PTR_ERR(power->usb);
490		goto usb_failed;
491	}
492
493	ret = device_create_file(&pdev->dev, &dev_attr_charger_state);
494	if (ret < 0)
495		dev_warn(wm8350->dev, "failed to add charge sysfs: %d\n", ret);
496	ret = 0;
497
498	wm8350_init_charger(wm8350);
499	if (wm8350_charger_config(wm8350, policy) == 0) {
500		wm8350_reg_unlock(wm8350);
501		wm8350_set_bits(wm8350, WM8350_POWER_MGMT_5, WM8350_CHG_ENA);
502		wm8350_reg_lock(wm8350);
503	}
504
505	return ret;
506
507usb_failed:
508	power_supply_unregister(power->battery);
509battery_failed:
510	power_supply_unregister(power->ac);
511
512	return ret;
513}
514
515static int wm8350_power_remove(struct platform_device *pdev)
516{
517	struct wm8350 *wm8350 = platform_get_drvdata(pdev);
518	struct wm8350_power *power = &wm8350->power;
519
520	free_charger_irq(wm8350);
521	device_remove_file(&pdev->dev, &dev_attr_charger_state);
522	power_supply_unregister(power->battery);
523	power_supply_unregister(power->ac);
524	power_supply_unregister(power->usb);
525	return 0;
526}
527
528static struct platform_driver wm8350_power_driver = {
529	.probe = wm8350_power_probe,
530	.remove = wm8350_power_remove,
531	.driver = {
532		.name = "wm8350-power",
533	},
534};
535
536module_platform_driver(wm8350_power_driver);
537
538MODULE_LICENSE("GPL");
539MODULE_DESCRIPTION("Power supply driver for WM8350");
540MODULE_ALIAS("platform:wm8350-power");
541