[deliverable/linux.git] / drivers / power / twl4030_madc_battery.c

/*
 * Dumb driver for LiIon batteries using TWL4030 madc.
 *
 * Copyright 2013 Golden Delicious Computers
 * Lukas Märdian <lukas@goldelico.com>
 *
 * Based on dumb driver for gta01 battery
 * Copyright 2009 Openmoko, Inc
 * Balaji Rao <balajirrao@openmoko.org>
 */

#include <linux/module.h>
#include <linux/param.h>
#include <linux/delay.h>
#include <linux/workqueue.h>
#include <linux/platform_device.h>
#include <linux/power_supply.h>
#include <linux/slab.h>
#include <linux/sort.h>
#include <linux/i2c/twl4030-madc.h>
#include <linux/power/twl4030_madc_battery.h>

struct twl4030_madc_battery {
	struct power_supply psy;
	struct twl4030_madc_bat_platform_data *pdata;
};

static enum power_supply_property twl4030_madc_bat_props[] = {
	POWER_SUPPLY_PROP_PRESENT,
	POWER_SUPPLY_PROP_STATUS,
	POWER_SUPPLY_PROP_TECHNOLOGY,
	POWER_SUPPLY_PROP_VOLTAGE_NOW,
	POWER_SUPPLY_PROP_CURRENT_NOW,
	POWER_SUPPLY_PROP_CAPACITY,
	POWER_SUPPLY_PROP_CHARGE_FULL,
	POWER_SUPPLY_PROP_CHARGE_NOW,
	POWER_SUPPLY_PROP_TEMP,
	POWER_SUPPLY_PROP_TIME_TO_EMPTY_NOW,
};

static int madc_read(int index)
{
	struct twl4030_madc_request req;
	int val;

	req.channels = index;
	req.method = TWL4030_MADC_SW2;
	req.type = TWL4030_MADC_WAIT;
	req.do_avg = 0;
	req.raw = false;
	req.func_cb = NULL;

	val = twl4030_madc_conversion(&req);
	if (val < 0)
		return val;

	return req.rbuf[ffs(index) - 1];
}

static int twl4030_madc_bat_get_charging_status(void)
{
	return (madc_read(TWL4030_MADC_ICHG) > 0) ? 1 : 0;
}

static int twl4030_madc_bat_get_voltage(void)
{
	return madc_read(TWL4030_MADC_VBAT);
}

static int twl4030_madc_bat_get_current(void)
{
	return madc_read(TWL4030_MADC_ICHG) * 1000;
}

static int twl4030_madc_bat_get_temp(void)
{
	return madc_read(TWL4030_MADC_BTEMP) * 10;
}

static int twl4030_madc_bat_voltscale(struct twl4030_madc_battery *bat,
					int volt)
{
	struct twl4030_madc_bat_calibration *calibration;
	int i, res = 0;

	/* choose charging curve */
	if (twl4030_madc_bat_get_charging_status())
		calibration = bat->pdata->charging;
	else
		calibration = bat->pdata->discharging;

	if (volt > calibration[0].voltage) {
		res = calibration[0].level;
	} else {
		for (i = 0; calibration[i+1].voltage >= 0; i++) {
			if (volt <= calibration[i].voltage &&
					volt >= calibration[i+1].voltage) {
				/* interval found - interpolate within range */
				res = calibration[i].level -
					((calibration[i].voltage - volt) *
					(calibration[i].level -
					calibration[i+1].level)) /
					(calibration[i].voltage -
					calibration[i+1].voltage);
				break;
			}
		}
	}
	return res;
}

static int twl4030_madc_bat_get_property(struct power_supply *psy,
					enum power_supply_property psp,
					union power_supply_propval *val)
{
	struct twl4030_madc_battery *bat = container_of(psy,
					struct twl4030_madc_battery, psy);

	switch (psp) {
	case POWER_SUPPLY_PROP_STATUS:
		if (twl4030_madc_bat_voltscale(bat,
				twl4030_madc_bat_get_voltage()) > 95)
			val->intval = POWER_SUPPLY_STATUS_FULL;
		else {
			if (twl4030_madc_bat_get_charging_status())
				val->intval = POWER_SUPPLY_STATUS_CHARGING;
			else
				val->intval = POWER_SUPPLY_STATUS_DISCHARGING;
		}
		break;
	case POWER_SUPPLY_PROP_VOLTAGE_NOW:
		val->intval = twl4030_madc_bat_get_voltage() * 1000;
		break;
	case POWER_SUPPLY_PROP_TECHNOLOGY:
		val->intval = POWER_SUPPLY_TECHNOLOGY_LION;
		break;
	case POWER_SUPPLY_PROP_CURRENT_NOW:
		val->intval = twl4030_madc_bat_get_current();
		break;
	case POWER_SUPPLY_PROP_PRESENT:
		/* assume battery is always present */
		val->intval = 1;
		break;
	case POWER_SUPPLY_PROP_CHARGE_NOW: {
			int percent = twl4030_madc_bat_voltscale(bat,
					twl4030_madc_bat_get_voltage());
			val->intval = (percent * bat->pdata->capacity) / 100;
			break;
		}
	case POWER_SUPPLY_PROP_CAPACITY:
		val->intval = twl4030_madc_bat_voltscale(bat,
					twl4030_madc_bat_get_voltage());
		break;
	case POWER_SUPPLY_PROP_CHARGE_FULL:
		val->intval = bat->pdata->capacity;
		break;
	case POWER_SUPPLY_PROP_TEMP:
		val->intval = twl4030_madc_bat_get_temp();
		break;
	case POWER_SUPPLY_PROP_TIME_TO_EMPTY_NOW: {
			int percent = twl4030_madc_bat_voltscale(bat,
					twl4030_madc_bat_get_voltage());
			/* in mAh */
			int chg = (percent * (bat->pdata->capacity/1000))/100;

			/* assume discharge with 400 mA (ca. 1.5W) */
			val->intval = (3600l * chg) / 400;
			break;
		}
	default:
		return -EINVAL;
	}

	return 0;
}

static void twl4030_madc_bat_ext_changed(struct power_supply *psy)
{
	struct twl4030_madc_battery *bat = container_of(psy,
					struct twl4030_madc_battery, psy);

	power_supply_changed(&bat->psy);
}

static int twl4030_cmp(const void *a, const void *b)
{
	return ((struct twl4030_madc_bat_calibration *)b)->voltage -
		((struct twl4030_madc_bat_calibration *)a)->voltage;
}

static int twl4030_madc_battery_probe(struct platform_device *pdev)
{
	struct twl4030_madc_battery *twl4030_madc_bat;
	struct twl4030_madc_bat_platform_data *pdata = pdev->dev.platform_data;

	twl4030_madc_bat = kzalloc(sizeof(*twl4030_madc_bat), GFP_KERNEL);
	if (!twl4030_madc_bat)
		return -ENOMEM;

	twl4030_madc_bat->psy.name = "twl4030_battery";
	twl4030_madc_bat->psy.type = POWER_SUPPLY_TYPE_BATTERY;
	twl4030_madc_bat->psy.properties = twl4030_madc_bat_props;
	twl4030_madc_bat->psy.num_properties =
					ARRAY_SIZE(twl4030_madc_bat_props);
	twl4030_madc_bat->psy.get_property = twl4030_madc_bat_get_property;
	twl4030_madc_bat->psy.external_power_changed =
					twl4030_madc_bat_ext_changed;

	/* sort charging and discharging calibration data */
	sort(pdata->charging, pdata->charging_size,
		sizeof(struct twl4030_madc_bat_calibration),
		twl4030_cmp, NULL);
	sort(pdata->discharging, pdata->discharging_size,
		sizeof(struct twl4030_madc_bat_calibration),
		twl4030_cmp, NULL);

	twl4030_madc_bat->pdata = pdata;
	platform_set_drvdata(pdev, twl4030_madc_bat);
	power_supply_register(&pdev->dev, &twl4030_madc_bat->psy);

	return 0;
}

static int twl4030_madc_battery_remove(struct platform_device *pdev)
{
	struct twl4030_madc_battery *bat = platform_get_drvdata(pdev);

	power_supply_unregister(&bat->psy);
	kfree(bat);

	return 0;
}

static struct platform_driver twl4030_madc_battery_driver = {
	.driver = {
		.name = "twl4030_madc_battery",
	},
	.probe  = twl4030_madc_battery_probe,
	.remove = twl4030_madc_battery_remove,
};
module_platform_driver(twl4030_madc_battery_driver);

MODULE_LICENSE("GPL");
MODULE_AUTHOR("Lukas Märdian <lukas@goldelico.com>");
MODULE_DESCRIPTION("twl4030_madc battery driver");
Commit	Line	Data
da0a00eb MB	1	/*
	2	* Dumb driver for LiIon batteries using TWL4030 madc.
	3	*
	4	* Copyright 2013 Golden Delicious Computers
	5	* Lukas Märdian <lukas@goldelico.com>
	6	*
	7	* Based on dumb driver for gta01 battery
	8	* Copyright 2009 Openmoko, Inc
	9	* Balaji Rao <balajirrao@openmoko.org>
	10	*/
	11
	12	#include <linux/module.h>
	13	#include <linux/param.h>
	14	#include <linux/delay.h>
	15	#include <linux/workqueue.h>
	16	#include <linux/platform_device.h>
	17	#include <linux/power_supply.h>
	18	#include <linux/slab.h>
	19	#include <linux/sort.h>
	20	#include <linux/i2c/twl4030-madc.h>
	21	#include <linux/power/twl4030_madc_battery.h>
	22
	23	struct twl4030_madc_battery {
	24	struct power_supply psy;
	25	struct twl4030_madc_bat_platform_data *pdata;
	26	};
	27
	28	static enum power_supply_property twl4030_madc_bat_props[] = {
	29	POWER_SUPPLY_PROP_PRESENT,
	30	POWER_SUPPLY_PROP_STATUS,
	31	POWER_SUPPLY_PROP_TECHNOLOGY,
	32	POWER_SUPPLY_PROP_VOLTAGE_NOW,
	33	POWER_SUPPLY_PROP_CURRENT_NOW,
	34	POWER_SUPPLY_PROP_CAPACITY,
	35	POWER_SUPPLY_PROP_CHARGE_FULL,
	36	POWER_SUPPLY_PROP_CHARGE_NOW,
	37	POWER_SUPPLY_PROP_TEMP,
	38	POWER_SUPPLY_PROP_TIME_TO_EMPTY_NOW,
	39	};
	40
	41	static int madc_read(int index)
	42	{
	43	struct twl4030_madc_request req;
	44	int val;
	45
	46	req.channels = index;
	47	req.method = TWL4030_MADC_SW2;
	48	req.type = TWL4030_MADC_WAIT;
	49	req.do_avg = 0;
	50	req.raw = false;
	51	req.func_cb = NULL;
	52
	53	val = twl4030_madc_conversion(&req);
	54	if (val < 0)
	55	return val;
	56
	57	return req.rbuf[ffs(index) - 1];
	58	}
	59
	60	static int twl4030_madc_bat_get_charging_status(void)
	61	{
	62	return (madc_read(TWL4030_MADC_ICHG) > 0) ? 1 : 0;
	63	}
	64
65	static int twl4030_madc_bat_get_voltage(void)
66	{
67	return madc_read(TWL4030_MADC_VBAT);
68	}
69
70	static int twl4030_madc_bat_get_current(void)
71	{
72	return madc_read(TWL4030_MADC_ICHG) * 1000;
73	}
74
75	static int twl4030_madc_bat_get_temp(void)
76	{
77	return madc_read(TWL4030_MADC_BTEMP) * 10;
78	}
79
80	static int twl4030_madc_bat_voltscale(struct twl4030_madc_battery *bat,
81	int volt)
82	{
83	struct twl4030_madc_bat_calibration *calibration;
84	int i, res = 0;
85
86	/* choose charging curve */
87	if (twl4030_madc_bat_get_charging_status())
88	calibration = bat->pdata->charging;
89	else
90	calibration = bat->pdata->discharging;
91
92	if (volt > calibration[0].voltage) {
93	res = calibration[0].level;
94	} else {
95	for (i = 0; calibration[i+1].voltage >= 0; i++) {
96	if (volt <= calibration[i].voltage &&
97	volt >= calibration[i+1].voltage) {
98	/* interval found - interpolate within range */
99	res = calibration[i].level -
100	((calibration[i].voltage - volt) *
101	(calibration[i].level -
102	calibration[i+1].level)) /
103	(calibration[i].voltage -
104	calibration[i+1].voltage);
105	break;
106	}
107	}
108	}
109	return res;
110	}
111
112	static int twl4030_madc_bat_get_property(struct power_supply *psy,
113	enum power_supply_property psp,
114	union power_supply_propval *val)
115	{
116	struct twl4030_madc_battery *bat = container_of(psy,
117	struct twl4030_madc_battery, psy);
118
119	switch (psp) {
120	case POWER_SUPPLY_PROP_STATUS:
121	if (twl4030_madc_bat_voltscale(bat,
122	twl4030_madc_bat_get_voltage()) > 95)
123	val->intval = POWER_SUPPLY_STATUS_FULL;
124	else {
125	if (twl4030_madc_bat_get_charging_status())
126	val->intval = POWER_SUPPLY_STATUS_CHARGING;
127	else
128	val->intval = POWER_SUPPLY_STATUS_DISCHARGING;
129	}
130	break;
131	case POWER_SUPPLY_PROP_VOLTAGE_NOW:
132	val->intval = twl4030_madc_bat_get_voltage() * 1000;
133	break;
134	case POWER_SUPPLY_PROP_TECHNOLOGY:
135	val->intval = POWER_SUPPLY_TECHNOLOGY_LION;
136	break;
137	case POWER_SUPPLY_PROP_CURRENT_NOW:
138	val->intval = twl4030_madc_bat_get_current();
139	break;
140	case POWER_SUPPLY_PROP_PRESENT:
141	/* assume battery is always present */
142	val->intval = 1;
143	break;
144	case POWER_SUPPLY_PROP_CHARGE_NOW: {
145	int percent = twl4030_madc_bat_voltscale(bat,
146	twl4030_madc_bat_get_voltage());
147	val->intval = (percent * bat->pdata->capacity) / 100;
148	break;
149	}
150	case POWER_SUPPLY_PROP_CAPACITY:
151	val->intval = twl4030_madc_bat_voltscale(bat,
152	twl4030_madc_bat_get_voltage());
153	break;
154	case POWER_SUPPLY_PROP_CHARGE_FULL:
155	val->intval = bat->pdata->capacity;
156	break;
157	case POWER_SUPPLY_PROP_TEMP:
158	val->intval = twl4030_madc_bat_get_temp();
159	break;
160	case POWER_SUPPLY_PROP_TIME_TO_EMPTY_NOW: {
161	int percent = twl4030_madc_bat_voltscale(bat,
162	twl4030_madc_bat_get_voltage());
163	/* in mAh */
164	int chg = (percent * (bat->pdata->capacity/1000))/100;
165
166	/* assume discharge with 400 mA (ca. 1.5W) */
167	val->intval = (3600l * chg) / 400;
168	break;
169	}
170	default:
171	return -EINVAL;
172	}
173
174	return 0;
175	}
176
177	static void twl4030_madc_bat_ext_changed(struct power_supply *psy)
178	{
179	struct twl4030_madc_battery *bat = container_of(psy,
180	struct twl4030_madc_battery, psy);
181
182	power_supply_changed(&bat->psy);
183	}
184
185	static int twl4030_cmp(const void a, const void b)
186	{
187	return ((struct twl4030_madc_bat_calibration *)b)->voltage -
188	((struct twl4030_madc_bat_calibration *)a)->voltage;
189	}
190
191	static int twl4030_madc_battery_probe(struct platform_device *pdev)
192	{
193	struct twl4030_madc_battery *twl4030_madc_bat;
194	struct twl4030_madc_bat_platform_data *pdata = pdev->dev.platform_data;
195
196	twl4030_madc_bat = kzalloc(sizeof(*twl4030_madc_bat), GFP_KERNEL);
197	if (!twl4030_madc_bat)
198	return -ENOMEM;
199
200	twl4030_madc_bat->psy.name = "twl4030_battery";
201	twl4030_madc_bat->psy.type = POWER_SUPPLY_TYPE_BATTERY;
202	twl4030_madc_bat->psy.properties = twl4030_madc_bat_props;
203	twl4030_madc_bat->psy.num_properties =
204	ARRAY_SIZE(twl4030_madc_bat_props);
205	twl4030_madc_bat->psy.get_property = twl4030_madc_bat_get_property;
206	twl4030_madc_bat->psy.external_power_changed =
207	twl4030_madc_bat_ext_changed;
208
209	/* sort charging and discharging calibration data */
210	sort(pdata->charging, pdata->charging_size,
211	sizeof(struct twl4030_madc_bat_calibration),
212	twl4030_cmp, NULL);
213	sort(pdata->discharging, pdata->discharging_size,
214	sizeof(struct twl4030_madc_bat_calibration),
215	twl4030_cmp, NULL);
216
217	twl4030_madc_bat->pdata = pdata;
218	platform_set_drvdata(pdev, twl4030_madc_bat);
219	power_supply_register(&pdev->dev, &twl4030_madc_bat->psy);
220
221	return 0;
222	}
223
224	static int twl4030_madc_battery_remove(struct platform_device *pdev)
225	{
226	struct twl4030_madc_battery *bat = platform_get_drvdata(pdev);
227
228	power_supply_unregister(&bat->psy);
229	kfree(bat);
230
231	return 0;
232	}
233
234	static struct platform_driver twl4030_madc_battery_driver = {
235	.driver = {
236	.name = "twl4030_madc_battery",
237	},
238	.probe = twl4030_madc_battery_probe,
239	.remove = twl4030_madc_battery_remove,
240	};
241	module_platform_driver(twl4030_madc_battery_driver);
242
243	MODULE_LICENSE("GPL");
244	MODULE_AUTHOR("Lukas Märdian <lukas@goldelico.com>");
245	MODULE_DESCRIPTION("twl4030_madc battery driver");