aboutsummaryrefslogtreecommitdiff
path: root/drivers/power/wm97xx_battery.c
blob: c2f09ed35050a15d20148c4439614b8098ee90a7 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
/*
 * linux/drivers/power/wm97xx_battery.c
 *
 * Battery measurement code for WM97xx
 *
 * based on tosa_battery.c
 *
 * Copyright (C) 2008 Marek Vasut <marek.vasut@gmail.com>
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License version 2 as
 * published by the Free Software Foundation.
 *
 */

#include <linux/init.h>
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/platform_device.h>
#include <linux/power_supply.h>
#include <linux/wm97xx.h>
#include <linux/spinlock.h>
#include <linux/interrupt.h>
#include <linux/gpio.h>
#include <linux/irq.h>
#include <linux/slab.h>

static struct work_struct bat_work;
static DEFINE_MUTEX(work_lock);
static int bat_status = POWER_SUPPLY_STATUS_UNKNOWN;
static enum power_supply_property *prop;

static unsigned long wm97xx_read_bat(struct power_supply *bat_ps)
{
	struct wm97xx_pdata *wmdata = bat_ps->dev.parent->platform_data;
	struct wm97xx_batt_pdata *pdata = wmdata->batt_pdata;

	return wm97xx_read_aux_adc(dev_get_drvdata(bat_ps->dev.parent),
					pdata->batt_aux) * pdata->batt_mult /
					pdata->batt_div;
}

static unsigned long wm97xx_read_temp(struct power_supply *bat_ps)
{
	struct wm97xx_pdata *wmdata = bat_ps->dev.parent->platform_data;
	struct wm97xx_batt_pdata *pdata = wmdata->batt_pdata;

	return wm97xx_read_aux_adc(dev_get_drvdata(bat_ps->dev.parent),
					pdata->temp_aux) * pdata->temp_mult /
					pdata->temp_div;
}

static int wm97xx_bat_get_property(struct power_supply *bat_ps,
			    enum power_supply_property psp,
			    union power_supply_propval *val)
{
	struct wm97xx_pdata *wmdata = bat_ps->dev.parent->platform_data;
	struct wm97xx_batt_pdata *pdata = wmdata->batt_pdata;

	switch (psp) {
	case POWER_SUPPLY_PROP_STATUS:
		val->intval = bat_status;
		break;
	case POWER_SUPPLY_PROP_TECHNOLOGY:
		val->intval = pdata->batt_tech;
		break;
	case POWER_SUPPLY_PROP_VOLTAGE_NOW:
		if (pdata->batt_aux >= 0)
			val->intval = wm97xx_read_bat(bat_ps);
		else
			return -EINVAL;
		break;
	case POWER_SUPPLY_PROP_TEMP:
		if (pdata->temp_aux >= 0)
			val->intval = wm97xx_read_temp(bat_ps);
		else
			return -EINVAL;
		break;
	case POWER_SUPPLY_PROP_VOLTAGE_MAX:
		if (pdata->max_voltage >= 0)
			val->intval = pdata->max_voltage;
		else
			return -EINVAL;
		break;
	case POWER_SUPPLY_PROP_VOLTAGE_MIN:
		if (pdata->min_voltage >= 0)
			val->intval = pdata->min_voltage;
		else
			return -EINVAL;
		break;
	case POWER_SUPPLY_PROP_PRESENT:
		val->intval = 1;
		break;
	default:
		return -EINVAL;
	}
	return 0;
}

static void wm97xx_bat_external_power_changed(struct power_supply *bat_ps)
{
	schedule_work(&bat_work);
}

static void wm97xx_bat_update(struct power_supply *bat_ps)
{
	int old_status = bat_status;
	struct wm97xx_pdata *wmdata = bat_ps->dev.parent->platform_data;
	struct wm97xx_batt_pdata *pdata = wmdata->batt_pdata;

	mutex_lock(&work_lock);

	bat_status = (pdata->charge_gpio >= 0) ?
			(gpio_get_value(pdata->charge_gpio) ?
			POWER_SUPPLY_STATUS_DISCHARGING :
			POWER_SUPPLY_STATUS_CHARGING) :
			POWER_SUPPLY_STATUS_UNKNOWN;

	if (old_status != bat_status) {
		pr_debug("%s: %i -> %i\n", bat_ps->desc->name, old_status,
					bat_status);
		power_supply_changed(bat_ps);
	}

	mutex_unlock(&work_lock);
}

static struct power_supply *bat_psy;
static struct power_supply_desc bat_psy_desc = {
	.type			= POWER_SUPPLY_TYPE_BATTERY,
	.get_property		= wm97xx_bat_get_property,
	.external_power_changed = wm97xx_bat_external_power_changed,
	.use_for_apm		= 1,
};

static void wm97xx_bat_work(struct work_struct *work)
{
	wm97xx_bat_update(bat_psy);
}

static irqreturn_t wm97xx_chrg_irq(int irq, void *data)
{
	schedule_work(&bat_work);
	return IRQ_HANDLED;
}

#ifdef CONFIG_PM
static int wm97xx_bat_suspend(struct device *dev)
{
	flush_work(&bat_work);
	return 0;
}

static int wm97xx_bat_resume(struct device *dev)
{
	schedule_work(&bat_work);
	return 0;
}

static const struct dev_pm_ops wm97xx_bat_pm_ops = {
	.suspend	= wm97xx_bat_suspend,
	.resume		= wm97xx_bat_resume,
};
#endif

static int wm97xx_bat_probe(struct platform_device *dev)
{
	int ret = 0;
	int props = 1;	/* POWER_SUPPLY_PROP_PRESENT */
	int i = 0;
	struct wm97xx_pdata *wmdata = dev->dev.platform_data;
	struct wm97xx_batt_pdata *pdata;

	if (!wmdata) {
		dev_err(&dev->dev, "No platform data supplied\n");
		return -EINVAL;
	}

	pdata = wmdata->batt_pdata;

	if (dev->id != -1)
		return -EINVAL;

	if (!pdata) {
		dev_err(&dev->dev, "No platform_data supplied\n");
		return -EINVAL;
	}

	if (gpio_is_valid(pdata->charge_gpio)) {
		ret = gpio_request(pdata->charge_gpio, "BATT CHRG");
		if (ret)
			goto err;
		ret = gpio_direction_input(pdata->charge_gpio);
		if (ret)
			goto err2;
		ret = request_irq(gpio_to_irq(pdata->charge_gpio),
				wm97xx_chrg_irq, 0,
				"AC Detect", dev);
		if (ret)
			goto err2;
		props++;	/* POWER_SUPPLY_PROP_STATUS */
	}

	if (pdata->batt_tech >= 0)
		props++;	/* POWER_SUPPLY_PROP_TECHNOLOGY */
	if (pdata->temp_aux >= 0)
		props++;	/* POWER_SUPPLY_PROP_TEMP */
	if (pdata->batt_aux >= 0)
		props++;	/* POWER_SUPPLY_PROP_VOLTAGE_NOW */
	if (pdata->max_voltage >= 0)
		props++;	/* POWER_SUPPLY_PROP_VOLTAGE_MAX */
	if (pdata->min_voltage >= 0)
		props++;	/* POWER_SUPPLY_PROP_VOLTAGE_MIN */

	prop = kzalloc(props * sizeof(*prop), GFP_KERNEL);
	if (!prop) {
		ret = -ENOMEM;
		goto err3;
	}

	prop[i++] = POWER_SUPPLY_PROP_PRESENT;
	if (pdata->charge_gpio >= 0)
		prop[i++] = POWER_SUPPLY_PROP_STATUS;
	if (pdata->batt_tech >= 0)
		prop[i++] = POWER_SUPPLY_PROP_TECHNOLOGY;
	if (pdata->temp_aux >= 0)
		prop[i++] = POWER_SUPPLY_PROP_TEMP;
	if (pdata->batt_aux >= 0)
		prop[i++] = POWER_SUPPLY_PROP_VOLTAGE_NOW;
	if (pdata->max_voltage >= 0)
		prop[i++] = POWER_SUPPLY_PROP_VOLTAGE_MAX;
	if (pdata->min_voltage >= 0)
		prop[i++] = POWER_SUPPLY_PROP_VOLTAGE_MIN;

	INIT_WORK(&bat_work, wm97xx_bat_work);

	if (!pdata->batt_name) {
		dev_info(&dev->dev, "Please consider setting proper battery "
				"name in platform definition file, falling "
				"back to name \"wm97xx-batt\"\n");
		bat_psy_desc.name = "wm97xx-batt";
	} else
		bat_psy_desc.name = pdata->batt_name;

	bat_psy_desc.properties = prop;
	bat_psy_desc.num_properties = props;

	bat_psy = power_supply_register(&dev->dev, &bat_psy_desc, NULL);
	if (!IS_ERR(bat_psy)) {
		schedule_work(&bat_work);
	} else {
		ret = PTR_ERR(bat_psy);
		goto err4;
	}

	return 0;
err4:
	kfree(prop);
err3:
	if (gpio_is_valid(pdata->charge_gpio))
		free_irq(gpio_to_irq(pdata->charge_gpio), dev);
err2:
	if (gpio_is_valid(pdata->charge_gpio))
		gpio_free(pdata->charge_gpio);
err:
	return ret;
}

static int wm97xx_bat_remove(struct platform_device *dev)
{
	struct wm97xx_pdata *wmdata = dev->dev.platform_data;
	struct wm97xx_batt_pdata *pdata = wmdata->batt_pdata;

	if (pdata && gpio_is_valid(pdata->charge_gpio)) {
		free_irq(gpio_to_irq(pdata->charge_gpio), dev);
		gpio_free(pdata->charge_gpio);
	}
	cancel_work_sync(&bat_work);
	power_supply_unregister(bat_psy);
	kfree(prop);
	return 0;
}

static struct platform_driver wm97xx_bat_driver = {
	.driver	= {
		.name	= "wm97xx-battery",
#ifdef CONFIG_PM
		.pm	= &wm97xx_bat_pm_ops,
#endif
	},
	.probe		= wm97xx_bat_probe,
	.remove		= wm97xx_bat_remove,
};

module_platform_driver(wm97xx_bat_driver);

MODULE_LICENSE("GPL");
MODULE_AUTHOR("Marek Vasut <marek.vasut@gmail.com>");
MODULE_DESCRIPTION("WM97xx battery driver");