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;
149	unsigned int lut_size;
150
151	if (!bat) {
152		dev_err(psy->dev, "no battery infos ?!\n");
153		return -EINVAL;
154	}
155
156	lut = bat->pdata->lut_noac;
157	lut_size = bat->pdata->lut_noac_cnt;
158
159	if (bat->volt_value < 0 || bat->cur_value < 0 ||
160		jiffies_to_msecs(jiffies - bat->timestamp) >
161			BAT_POLL_INTERVAL) {
162		bat->volt_value = gather_samples(bat->client,
163			bat->pdata->volt_samples,
164			bat->pdata->volt_channel) * bat->pdata->volt_mult;
165		bat->cur_value = gather_samples(bat->client,
166			bat->pdata->current_samples,
167			bat->pdata->current_channel) * bat->pdata->current_mult;
168		bat->timestamp = jiffies;
169	}
170
171	if (bat->cable_plugged &&
172		((bat->pdata->gpio_charge_finished < 0) ||
173		!charge_finished(bat))) {
174		lut = bat->pdata->lut_acin;
175		lut_size = bat->pdata->lut_acin_cnt;
176	}
177
178	new_level = 100000;
179	full_volt = calc_full_volt((bat->volt_value / 1000),
180		(bat->cur_value / 1000), bat->pdata->internal_impedance);
181
182	if (full_volt < calc_full_volt(lut->volt, lut->cur,
183		bat->pdata->internal_impedance)) {
184		lut_size--;
185		while (lut_size--) {
186			int lut_volt1;
187			int lut_volt2;
188
189			lut_volt1 = calc_full_volt(lut[0].volt, lut[0].cur,
190				bat->pdata->internal_impedance);
191			lut_volt2 = calc_full_volt(lut[1].volt, lut[1].cur,
192				bat->pdata->internal_impedance);
193			if (full_volt < lut_volt1 && full_volt >= lut_volt2) {
194				new_level = (lut[1].level +
195					(lut[0].level - lut[1].level) *
196					(full_volt - lut_volt2) /
197					(lut_volt1 - lut_volt2)) * 1000;
198				break;
199			}
200			new_level = lut[1].level * 1000;
201			lut++;
202		}
203	}
204
205	bat->level = new_level;
206
207	switch (psp) {
208	case POWER_SUPPLY_PROP_STATUS:
209		if (bat->pdata->gpio_charge_finished < 0)
210			val->intval = bat->level == 100000 ?
211				POWER_SUPPLY_STATUS_FULL : bat->status;
212		else
213			val->intval = bat->status;
214		return 0;
215	case POWER_SUPPLY_PROP_CHARGE_FULL_DESIGN:
216		val->intval = 100000;
217		return 0;
218	case POWER_SUPPLY_PROP_CHARGE_EMPTY_DESIGN:
219		val->intval = 0;
220		return 0;
221	case POWER_SUPPLY_PROP_CHARGE_NOW:
222		val->intval = bat->level;
223		return 0;
224	case POWER_SUPPLY_PROP_VOLTAGE_NOW:
225		val->intval = bat->volt_value;
226		return 0;
227	case POWER_SUPPLY_PROP_CURRENT_NOW:
228		val->intval = bat->cur_value;
229		return 0;
230	default:
231		return -EINVAL;
232	}
233}
234
235static struct s3c_adc_bat main_bat = {
236	.psy = {
237		.name			= "main-battery",
238		.type			= POWER_SUPPLY_TYPE_BATTERY,
239		.properties		= s3c_adc_main_bat_props,
240		.num_properties		= ARRAY_SIZE(s3c_adc_main_bat_props),
241		.get_property		= s3c_adc_bat_get_property,
242		.external_power_changed = s3c_adc_bat_ext_power_changed,
243		.use_for_apm		= 1,
244	},
245};
246
247static void s3c_adc_bat_work(struct work_struct *work)
248{
249	struct s3c_adc_bat *bat = &main_bat;
250	int is_charged;
251	int is_plugged;
252	static int was_plugged;
253
254	is_plugged = power_supply_am_i_supplied(&bat->psy);
255	bat->cable_plugged = is_plugged;
256	if (is_plugged != was_plugged) {
257		was_plugged = is_plugged;
258		if (is_plugged) {
259			if (bat->pdata->enable_charger)
260				bat->pdata->enable_charger();
261			bat->status = POWER_SUPPLY_STATUS_CHARGING;
262		} else {
263			if (bat->pdata->disable_charger)
264				bat->pdata->disable_charger();
265			bat->status = POWER_SUPPLY_STATUS_DISCHARGING;
266		}
267	} else {
268		if ((bat->pdata->gpio_charge_finished >= 0) && is_plugged) {
269			is_charged = charge_finished(&main_bat);
270			if (is_charged) {
271				if (bat->pdata->disable_charger)
272					bat->pdata->disable_charger();
273				bat->status = POWER_SUPPLY_STATUS_FULL;
274			} else {
275				if (bat->pdata->enable_charger)
276					bat->pdata->enable_charger();
277				bat->status = POWER_SUPPLY_STATUS_CHARGING;
278			}
279		}
280	}
281
282	power_supply_changed(&bat->psy);
283}
284
285static irqreturn_t s3c_adc_bat_charged(int irq, void *dev_id)
286{
287	schedule_delayed_work(&bat_work,
288		msecs_to_jiffies(JITTER_DELAY));
289	return IRQ_HANDLED;
290}
291
292static int s3c_adc_bat_probe(struct platform_device *pdev)
293{
294	struct s3c_adc_client	*client;
295	struct s3c_adc_bat_pdata *pdata = pdev->dev.platform_data;
296	int ret;
297
298	client = s3c_adc_register(pdev, NULL, NULL, 0);
299	if (IS_ERR(client)) {
300		dev_err(&pdev->dev, "cannot register adc\n");
301		return PTR_ERR(client);
302	}
303
304	platform_set_drvdata(pdev, client);
305
306	main_bat.client = client;
307	main_bat.pdata = pdata;
308	main_bat.volt_value = -1;
309	main_bat.cur_value = -1;
310	main_bat.cable_plugged = 0;
311	main_bat.status = POWER_SUPPLY_STATUS_DISCHARGING;
312
313	ret = power_supply_register(&pdev->dev, &main_bat.psy);
314	if (ret)
315		goto err_reg_main;
316	if (pdata->backup_volt_mult) {
317		backup_bat.client = client;
318		backup_bat.pdata = pdev->dev.platform_data;
319		backup_bat.volt_value = -1;
320		ret = power_supply_register(&pdev->dev, &backup_bat.psy);
321		if (ret)
322			goto err_reg_backup;
323	}
324
325	INIT_DELAYED_WORK(&bat_work, s3c_adc_bat_work);
326
327	if (pdata->gpio_charge_finished >= 0) {
328		ret = gpio_request(pdata->gpio_charge_finished, "charged");
329		if (ret)
330			goto err_gpio;
331
332		ret = request_irq(gpio_to_irq(pdata->gpio_charge_finished),
333				s3c_adc_bat_charged,
334				IRQF_TRIGGER_RISING | IRQF_TRIGGER_FALLING,
335				"battery charged", NULL);
336		if (ret)
337			goto err_irq;
338	}
339
340	if (pdata->init) {
341		ret = pdata->init();
342		if (ret)
343			goto err_platform;
344	}
345
346	dev_info(&pdev->dev, "successfully loaded\n");
347	device_init_wakeup(&pdev->dev, 1);
348
349	/* Schedule timer to check current status */
350	schedule_delayed_work(&bat_work,
351		msecs_to_jiffies(JITTER_DELAY));
352
353	return 0;
354
355err_platform:
356	if (pdata->gpio_charge_finished >= 0)
357		free_irq(gpio_to_irq(pdata->gpio_charge_finished), NULL);
358err_irq:
359	if (pdata->gpio_charge_finished >= 0)
360		gpio_free(pdata->gpio_charge_finished);
361err_gpio:
362	if (pdata->backup_volt_mult)
363		power_supply_unregister(&backup_bat.psy);
364err_reg_backup:
365	power_supply_unregister(&main_bat.psy);
366err_reg_main:
367	return ret;
368}
369
370static int s3c_adc_bat_remove(struct platform_device *pdev)
371{
372	struct s3c_adc_client *client = platform_get_drvdata(pdev);
373	struct s3c_adc_bat_pdata *pdata = pdev->dev.platform_data;
374
375	power_supply_unregister(&main_bat.psy);
376	if (pdata->backup_volt_mult)
377		power_supply_unregister(&backup_bat.psy);
378
379	s3c_adc_release(client);
380
381	if (pdata->gpio_charge_finished >= 0) {
382		free_irq(gpio_to_irq(pdata->gpio_charge_finished), NULL);
383		gpio_free(pdata->gpio_charge_finished);
384	}
385
386	cancel_delayed_work(&bat_work);
387
388	if (pdata->exit)
389		pdata->exit();
390
391	return 0;
392}
393
394#ifdef CONFIG_PM
395static int s3c_adc_bat_suspend(struct platform_device *pdev,
396	pm_message_t state)
397{
398	struct s3c_adc_bat_pdata *pdata = pdev->dev.platform_data;
399
400	if (pdata->gpio_charge_finished >= 0) {
401		if (device_may_wakeup(&pdev->dev))
402			enable_irq_wake(
403				gpio_to_irq(pdata->gpio_charge_finished));
404		else {
405			disable_irq(gpio_to_irq(pdata->gpio_charge_finished));
406			main_bat.pdata->disable_charger();
407		}
408	}
409
410	return 0;
411}
412
413static int s3c_adc_bat_resume(struct platform_device *pdev)
414{
415	struct s3c_adc_bat_pdata *pdata = pdev->dev.platform_data;
416
417	if (pdata->gpio_charge_finished >= 0) {
418		if (device_may_wakeup(&pdev->dev))
419			disable_irq_wake(
420				gpio_to_irq(pdata->gpio_charge_finished));
421		else
422			enable_irq(gpio_to_irq(pdata->gpio_charge_finished));
423	}
424
425	/* Schedule timer to check current status */
426	schedule_delayed_work(&bat_work,
427		msecs_to_jiffies(JITTER_DELAY));
428
429	return 0;
430}
431#else
432#define s3c_adc_bat_suspend NULL
433#define s3c_adc_bat_resume NULL
434#endif
435
436static struct platform_driver s3c_adc_bat_driver = {
437	.driver		= {
438		.name	= "s3c-adc-battery",
439	},
440	.probe		= s3c_adc_bat_probe,
441	.remove		= s3c_adc_bat_remove,
442	.suspend	= s3c_adc_bat_suspend,
443	.resume		= s3c_adc_bat_resume,
444};
445
446module_platform_driver(s3c_adc_bat_driver);
447
448MODULE_AUTHOR("Vasily Khoruzhick <anarsoul@gmail.com>");
449MODULE_DESCRIPTION("iPAQ H1930/H1940/RX1950 battery controller driver");
450MODULE_LICENSE("GPL");
451