1/*
2 *	iPAQ h1930/h1940/rx1950 battery controller driver
3 *	Copyright (c) Vasily Khoruzhick
4 *	Based on h1940_battery.c by Arnaud Patard
5 *
6 * This file is subject to the terms and conditions of the GNU General Public
7 * License.  See the file COPYING in the main directory of this archive for
8 * more details.
9 *
10 */
11
12#include <linux/interrupt.h>
13#include <linux/platform_device.h>
14#include <linux/power_supply.h>
15#include <linux/leds.h>
16#include <linux/gpio.h>
17#include <linux/err.h>
18#include <linux/timer.h>
19#include <linux/jiffies.h>
20#include <linux/s3c_adc_battery.h>
21#include <linux/errno.h>
22#include <linux/init.h>
23#include <linux/module.h>
24
25#include <plat/adc.h>
26
27#define BAT_POLL_INTERVAL		10000 /* ms */
28#define JITTER_DELAY			500 /* ms */
29
30struct s3c_adc_bat {
31	struct power_supply		psy;
32	struct s3c_adc_client		*client;
33	struct s3c_adc_bat_pdata	*pdata;
34	int				volt_value;
35	int				cur_value;
36	unsigned int			timestamp;
37	int				level;
38	int				status;
39	int				cable_plugged:1;
40};
41
42static struct delayed_work bat_work;
43
44static void s3c_adc_bat_ext_power_changed(struct power_supply *psy)
45{
46	schedule_delayed_work(&bat_work,
47		msecs_to_jiffies(JITTER_DELAY));
48}
49
50static int gather_samples(struct s3c_adc_client *client, int num, int channel)
51{
52	int value, i;
53
54	/* default to 1 if nothing is set */
55	if (num < 1)
56		num = 1;
57
58	value = 0;
59	for (i = 0; i < num; i++)
60		value += s3c_adc_read(client, channel);
61	value /= num;
62
63	return value;
64}
65
66static enum power_supply_property s3c_adc_backup_bat_props[] = {
67	POWER_SUPPLY_PROP_VOLTAGE_NOW,
68	POWER_SUPPLY_PROP_VOLTAGE_MIN,
69	POWER_SUPPLY_PROP_VOLTAGE_MAX_DESIGN,
70};
71
72static int s3c_adc_backup_bat_get_property(struct power_supply *psy,
73				enum power_supply_property psp,
74				union power_supply_propval *val)
75{
76	struct s3c_adc_bat *bat = container_of(psy, struct s3c_adc_bat, psy);
77
78	if (!bat) {
79		dev_err(psy->dev, "%s: no battery infos ?!\n", __func__);
80		return -EINVAL;
81	}
82
83	if (bat->volt_value < 0 ||
84		jiffies_to_msecs(jiffies - bat->timestamp) >
85			BAT_POLL_INTERVAL) {
86		bat->volt_value = gather_samples(bat->client,
87			bat->pdata->backup_volt_samples,
88			bat->pdata->backup_volt_channel);
89		bat->volt_value *= bat->pdata->backup_volt_mult;
90		bat->timestamp = jiffies;
91	}
92
93	switch (psp) {
94	case POWER_SUPPLY_PROP_VOLTAGE_NOW:
95		val->intval = bat->volt_value;
96		return 0;
97	case POWER_SUPPLY_PROP_VOLTAGE_MIN:
98		val->intval = bat->pdata->backup_volt_min;
99		return 0;
100	case POWER_SUPPLY_PROP_VOLTAGE_MAX_DESIGN:
101		val->intval = bat->pdata->backup_volt_max;
102		return 0;
103	default:
104		return -EINVAL;
105	}
106}
107
108static struct s3c_adc_bat backup_bat = {
109	.psy = {
110		.name		= "backup-battery",
111		.type		= POWER_SUPPLY_TYPE_BATTERY,
112		.properties	= s3c_adc_backup_bat_props,
113		.num_properties = ARRAY_SIZE(s3c_adc_backup_bat_props),
114		.get_property	= s3c_adc_backup_bat_get_property,
115		.use_for_apm	= 1,
116	},
117};
118
119static enum power_supply_property s3c_adc_main_bat_props[] = {
120	POWER_SUPPLY_PROP_STATUS,
121	POWER_SUPPLY_PROP_CHARGE_FULL_DESIGN,
122	POWER_SUPPLY_PROP_CHARGE_EMPTY_DESIGN,
123	POWER_SUPPLY_PROP_CHARGE_NOW,
124	POWER_SUPPLY_PROP_VOLTAGE_NOW,
125	POWER_SUPPLY_PROP_CURRENT_NOW,
126};
127
128static int calc_full_volt(int volt_val, int cur_val, int impedance)
129{
130	return volt_val + cur_val * impedance / 1000;
131}
132
133static int charge_finished(struct s3c_adc_bat *bat)
134{
135	return bat->pdata->gpio_inverted ?
136		!gpio_get_value(bat->pdata->gpio_charge_finished) :
137		gpio_get_value(bat->pdata->gpio_charge_finished);
138}
139
140static int s3c_adc_bat_get_property(struct power_supply *psy,
141				    enum power_supply_property psp,
142				    union power_supply_propval *val)
143{
144	struct s3c_adc_bat *bat = container_of(psy, struct s3c_adc_bat, psy);
145
146	int new_level;
147	int full_volt;
148	const struct s3c_adc_bat_thresh *lut = bat->pdata->lut_noac;
149	unsigned int lut_size = bat->pdata->lut_noac_cnt;
150
151	if (!bat) {
152		dev_err(psy->dev, "no battery infos ?!\n");
153		return -EINVAL;
154	}
155
156	if (bat->volt_value < 0 || bat->cur_value < 0 ||
157		jiffies_to_msecs(jiffies - bat->timestamp) >
158			BAT_POLL_INTERVAL) {
159		bat->volt_value = gather_samples(bat->client,
160			bat->pdata->volt_samples,
161			bat->pdata->volt_channel) * bat->pdata->volt_mult;
162		bat->cur_value = gather_samples(bat->client,
163			bat->pdata->current_samples,
164			bat->pdata->current_channel) * bat->pdata->current_mult;
165		bat->timestamp = jiffies;
166	}
167
168	if (bat->cable_plugged &&
169		((bat->pdata->gpio_charge_finished < 0) ||
170		!charge_finished(bat))) {
171		lut = bat->pdata->lut_acin;
172		lut_size = bat->pdata->lut_acin_cnt;
173	}
174
175	new_level = 100000;
176	full_volt = calc_full_volt((bat->volt_value / 1000),
177		(bat->cur_value / 1000), bat->pdata->internal_impedance);
178
179	if (full_volt < calc_full_volt(lut->volt, lut->cur,
180		bat->pdata->internal_impedance)) {
181		lut_size--;
182		while (lut_size--) {
183			int lut_volt1;
184			int lut_volt2;
185
186			lut_volt1 = calc_full_volt(lut[0].volt, lut[0].cur,
187				bat->pdata->internal_impedance);
188			lut_volt2 = calc_full_volt(lut[1].volt, lut[1].cur,
189				bat->pdata->internal_impedance);
190			if (full_volt < lut_volt1 && full_volt >= lut_volt2) {
191				new_level = (lut[1].level +
192					(lut[0].level - lut[1].level) *
193					(full_volt - lut_volt2) /
194					(lut_volt1 - lut_volt2)) * 1000;
195				break;
196			}
197			new_level = lut[1].level * 1000;
198			lut++;
199		}
200	}
201
202	bat->level = new_level;
203
204	switch (psp) {
205	case POWER_SUPPLY_PROP_STATUS:
206		if (bat->pdata->gpio_charge_finished < 0)
207			val->intval = bat->level == 100000 ?
208				POWER_SUPPLY_STATUS_FULL : bat->status;
209		else
210			val->intval = bat->status;
211		return 0;
212	case POWER_SUPPLY_PROP_CHARGE_FULL_DESIGN:
213		val->intval = 100000;
214		return 0;
215	case POWER_SUPPLY_PROP_CHARGE_EMPTY_DESIGN:
216		val->intval = 0;
217		return 0;
218	case POWER_SUPPLY_PROP_CHARGE_NOW:
219		val->intval = bat->level;
220		return 0;
221	case POWER_SUPPLY_PROP_VOLTAGE_NOW:
222		val->intval = bat->volt_value;
223		return 0;
224	case POWER_SUPPLY_PROP_CURRENT_NOW:
225		val->intval = bat->cur_value;
226		return 0;
227	default:
228		return -EINVAL;
229	}
230}
231
232static struct s3c_adc_bat main_bat = {
233	.psy = {
234		.name			= "main-battery",
235		.type			= POWER_SUPPLY_TYPE_BATTERY,
236		.properties		= s3c_adc_main_bat_props,
237		.num_properties		= ARRAY_SIZE(s3c_adc_main_bat_props),
238		.get_property		= s3c_adc_bat_get_property,
239		.external_power_changed = s3c_adc_bat_ext_power_changed,
240		.use_for_apm		= 1,
241	},
242};
243
244static void s3c_adc_bat_work(struct work_struct *work)
245{
246	struct s3c_adc_bat *bat = &main_bat;
247	int is_charged;
248	int is_plugged;
249	static int was_plugged;
250
251	is_plugged = power_supply_am_i_supplied(&bat->psy);
252	bat->cable_plugged = is_plugged;
253	if (is_plugged != was_plugged) {
254		was_plugged = is_plugged;
255		if (is_plugged) {
256			if (bat->pdata->enable_charger)
257				bat->pdata->enable_charger();
258			bat->status = POWER_SUPPLY_STATUS_CHARGING;
259		} else {
260			if (bat->pdata->disable_charger)
261				bat->pdata->disable_charger();
262			bat->status = POWER_SUPPLY_STATUS_DISCHARGING;
263		}
264	} else {
265		if ((bat->pdata->gpio_charge_finished >= 0) && is_plugged) {
266			is_charged = charge_finished(&main_bat);
267			if (is_charged) {
268				if (bat->pdata->disable_charger)
269					bat->pdata->disable_charger();
270				bat->status = POWER_SUPPLY_STATUS_FULL;
271			} else {
272				if (bat->pdata->enable_charger)
273					bat->pdata->enable_charger();
274				bat->status = POWER_SUPPLY_STATUS_CHARGING;
275			}
276		}
277	}
278
279	power_supply_changed(&bat->psy);
280}
281
282static irqreturn_t s3c_adc_bat_charged(int irq, void *dev_id)
283{
284	schedule_delayed_work(&bat_work,
285		msecs_to_jiffies(JITTER_DELAY));
286	return IRQ_HANDLED;
287}
288
289static int __devinit s3c_adc_bat_probe(struct platform_device *pdev)
290{
291	struct s3c_adc_client	*client;
292	struct s3c_adc_bat_pdata *pdata = pdev->dev.platform_data;
293	int ret;
294
295	client = s3c_adc_register(pdev, NULL, NULL, 0);
296	if (IS_ERR(client)) {
297		dev_err(&pdev->dev, "cannot register adc\n");
298		return PTR_ERR(client);
299	}
300
301	platform_set_drvdata(pdev, client);
302
303	main_bat.client = client;
304	main_bat.pdata = pdata;
305	main_bat.volt_value = -1;
306	main_bat.cur_value = -1;
307	main_bat.cable_plugged = 0;
308	main_bat.status = POWER_SUPPLY_STATUS_DISCHARGING;
309
310	ret = power_supply_register(&pdev->dev, &main_bat.psy);
311	if (ret)
312		goto err_reg_main;
313	if (pdata->backup_volt_mult) {
314		backup_bat.client = client;
315		backup_bat.pdata = pdev->dev.platform_data;
316		backup_bat.volt_value = -1;
317		ret = power_supply_register(&pdev->dev, &backup_bat.psy);
318		if (ret)
319			goto err_reg_backup;
320	}
321
322	INIT_DELAYED_WORK(&bat_work, s3c_adc_bat_work);
323
324	if (pdata->gpio_charge_finished >= 0) {
325		ret = gpio_request(pdata->gpio_charge_finished, "charged");
326		if (ret)
327			goto err_gpio;
328
329		ret = request_irq(gpio_to_irq(pdata->gpio_charge_finished),
330				s3c_adc_bat_charged,
331				IRQF_TRIGGER_RISING | IRQF_TRIGGER_FALLING,
332				"battery charged", NULL);
333		if (ret)
334			goto err_irq;
335	}
336
337	if (pdata->init) {
338		ret = pdata->init();
339		if (ret)
340			goto err_platform;
341	}
342
343	dev_info(&pdev->dev, "successfully loaded\n");
344	device_init_wakeup(&pdev->dev, 1);
345
346	/* Schedule timer to check current status */
347	schedule_delayed_work(&bat_work,
348		msecs_to_jiffies(JITTER_DELAY));
349
350	return 0;
351
352err_platform:
353	if (pdata->gpio_charge_finished >= 0)
354		free_irq(gpio_to_irq(pdata->gpio_charge_finished), NULL);
355err_irq:
356	if (pdata->gpio_charge_finished >= 0)
357		gpio_free(pdata->gpio_charge_finished);
358err_gpio:
359	if (pdata->backup_volt_mult)
360		power_supply_unregister(&backup_bat.psy);
361err_reg_backup:
362	power_supply_unregister(&main_bat.psy);
363err_reg_main:
364	return ret;
365}
366
367static int s3c_adc_bat_remove(struct platform_device *pdev)
368{
369	struct s3c_adc_client *client = platform_get_drvdata(pdev);
370	struct s3c_adc_bat_pdata *pdata = pdev->dev.platform_data;
371
372	power_supply_unregister(&main_bat.psy);
373	if (pdata->backup_volt_mult)
374		power_supply_unregister(&backup_bat.psy);
375
376	s3c_adc_release(client);
377
378	if (pdata->gpio_charge_finished >= 0) {
379		free_irq(gpio_to_irq(pdata->gpio_charge_finished), NULL);
380		gpio_free(pdata->gpio_charge_finished);
381	}
382
383	cancel_delayed_work(&bat_work);
384
385	if (pdata->exit)
386		pdata->exit();
387
388	return 0;
389}
390
391#ifdef CONFIG_PM
392static int s3c_adc_bat_suspend(struct platform_device *pdev,
393	pm_message_t state)
394{
395	struct s3c_adc_bat_pdata *pdata = pdev->dev.platform_data;
396
397	if (pdata->gpio_charge_finished >= 0) {
398		if (device_may_wakeup(&pdev->dev))
399			enable_irq_wake(
400				gpio_to_irq(pdata->gpio_charge_finished));
401		else {
402			disable_irq(gpio_to_irq(pdata->gpio_charge_finished));
403			main_bat.pdata->disable_charger();
404		}
405	}
406
407	return 0;
408}
409
410static int s3c_adc_bat_resume(struct platform_device *pdev)
411{
412	struct s3c_adc_bat_pdata *pdata = pdev->dev.platform_data;
413
414	if (pdata->gpio_charge_finished >= 0) {
415		if (device_may_wakeup(&pdev->dev))
416			disable_irq_wake(
417				gpio_to_irq(pdata->gpio_charge_finished));
418		else
419			enable_irq(gpio_to_irq(pdata->gpio_charge_finished));
420	}
421
422	/* Schedule timer to check current status */
423	schedule_delayed_work(&bat_work,
424		msecs_to_jiffies(JITTER_DELAY));
425
426	return 0;
427}
428#else
429#define s3c_adc_bat_suspend NULL
430#define s3c_adc_bat_resume NULL
431#endif
432
433static struct platform_driver s3c_adc_bat_driver = {
434	.driver		= {
435		.name	= "s3c-adc-battery",
436	},
437	.probe		= s3c_adc_bat_probe,
438	.remove		= s3c_adc_bat_remove,
439	.suspend	= s3c_adc_bat_suspend,
440	.resume		= s3c_adc_bat_resume,
441};
442
443module_platform_driver(s3c_adc_bat_driver);
444
445MODULE_AUTHOR("Vasily Khoruzhick <anarsoul@gmail.com>");
446MODULE_DESCRIPTION("iPAQ H1930/H1940/RX1950 battery controller driver");
447MODULE_LICENSE("GPL");
448