summaryrefslogtreecommitdiffstats
path: root/drivers/power/palmtx_battery.c
blob: 244bb273a6371feb081ec239b9b0a0941d7c9433 (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
/*
 * linux/drivers/power/palmtx_battery.c
 *
 * Battery measurement code for Palm T|X Handheld computer
 *
 * 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/kernel.h>
#include <linux/module.h>
#include <linux/power_supply.h>
#include <linux/wm97xx.h>
#include <linux/delay.h>
#include <linux/spinlock.h>
#include <linux/interrupt.h>
#include <linux/gpio.h>

#include <asm/mach-types.h>
#include <asm/arch/palmtx.h>

static DEFINE_MUTEX(bat_lock);
static struct work_struct bat_work;
struct mutex work_lock;
int bat_status = POWER_SUPPLY_STATUS_DISCHARGING;

static unsigned long palmtx_read_bat(struct power_supply *bat_ps)
{
	return wm97xx_read_aux_adc(bat_ps->dev->parent->driver_data,
				    WM97XX_AUX_ID3) * 1000 / 414;
}

static unsigned long palmtx_read_temp(struct power_supply *bat_ps)
{
	return wm97xx_read_aux_adc(bat_ps->dev->parent->driver_data,
				    WM97XX_AUX_ID2);
}

static int palmtx_bat_get_property(struct power_supply *bat_ps,
			    enum power_supply_property psp,
			    union power_supply_propval *val)
{
	switch (psp) {
	case POWER_SUPPLY_PROP_STATUS:
		val->intval = bat_status;
		break;
	case POWER_SUPPLY_PROP_TECHNOLOGY:
		val->intval = POWER_SUPPLY_TECHNOLOGY_LIPO;
		break;
	case POWER_SUPPLY_PROP_VOLTAGE_NOW:
		val->intval = palmtx_read_bat(bat_ps);
		break;
	case POWER_SUPPLY_PROP_VOLTAGE_MAX:
	case POWER_SUPPLY_PROP_VOLTAGE_MAX_DESIGN:
		val->intval = PALMTX_BAT_MAX_VOLTAGE;
		break;
	case POWER_SUPPLY_PROP_VOLTAGE_MIN_DESIGN:
		val->intval = PALMTX_BAT_MIN_VOLTAGE;
		break;
	case POWER_SUPPLY_PROP_TEMP:
		val->intval = palmtx_read_temp(bat_ps);
		break;
	case POWER_SUPPLY_PROP_PRESENT:
		val->intval = 1;
		break;
	default:
		return -EINVAL;
	}
	return 0;
}

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

static char *status_text[] = {
	[POWER_SUPPLY_STATUS_UNKNOWN] =		"Unknown",
	[POWER_SUPPLY_STATUS_CHARGING] =	"Charging",
	[POWER_SUPPLY_STATUS_DISCHARGING] =	"Discharging",
};

static void palmtx_bat_update(struct power_supply *bat_ps)
{
	int old_status = bat_status;

	mutex_lock(&work_lock);

	bat_status = gpio_get_value(GPIO_NR_PALMTX_POWER_DETECT) ?
				    POWER_SUPPLY_STATUS_CHARGING :
				    POWER_SUPPLY_STATUS_DISCHARGING;

	if (old_status != bat_status) {
		pr_debug("%s %s -> %s\n", bat_ps->name,
				status_text[old_status],
				status_text[bat_status]);
		power_supply_changed(bat_ps);
	}

	mutex_unlock(&work_lock);
}

static enum power_supply_property palmtx_bat_main_props[] = {
	POWER_SUPPLY_PROP_STATUS,
	POWER_SUPPLY_PROP_TECHNOLOGY,
	POWER_SUPPLY_PROP_VOLTAGE_NOW,
	POWER_SUPPLY_PROP_VOLTAGE_MAX,
	POWER_SUPPLY_PROP_VOLTAGE_MIN_DESIGN,
	POWER_SUPPLY_PROP_TEMP,
	POWER_SUPPLY_PROP_PRESENT,
};

struct power_supply bat_ps = {
	.name			= "main-battery",
	.type			= POWER_SUPPLY_TYPE_BATTERY,
	.properties		= palmtx_bat_main_props,
	.num_properties		= ARRAY_SIZE(palmtx_bat_main_props),
	.get_property		= palmtx_bat_get_property,
	.external_power_changed = palmtx_bat_external_power_changed,
	.use_for_apm		= 1,
};

static void palmtx_bat_work(struct work_struct *work)
{
	palmtx_bat_update(&bat_ps);
}

#ifdef CONFIG_PM
static int palmtx_bat_suspend(struct platform_device *dev, pm_message_t state)
{
	flush_scheduled_work();
	return 0;
}

static int palmtx_bat_resume(struct platform_device *dev)
{
	schedule_work(&bat_work);
	return 0;
}
#else
#define palmtx_bat_suspend NULL
#define palmtx_bat_resume NULL
#endif

static int __devinit palmtx_bat_probe(struct platform_device *dev)
{
	int ret = 0;

	if (!machine_is_palmtx())
		return -ENODEV;

	mutex_init(&work_lock);

	INIT_WORK(&bat_work, palmtx_bat_work);

	ret = power_supply_register(&dev->dev, &bat_ps);
	if (!ret)
		schedule_work(&bat_work);

	return ret;
}

static int __devexit palmtx_bat_remove(struct platform_device *dev)
{
	power_supply_unregister(&bat_ps);
	return 0;
}

static struct platform_driver palmtx_bat_driver = {
	.driver.name	= "wm97xx-battery",
	.driver.owner	= THIS_MODULE,
	.probe		= palmtx_bat_probe,
	.remove		= __devexit_p(palmtx_bat_remove),
	.suspend	= palmtx_bat_suspend,
	.resume		= palmtx_bat_resume,
};

static int __init palmtx_bat_init(void)
{
	return platform_driver_register(&palmtx_bat_driver);
}

static void __exit palmtx_bat_exit(void)
{
	platform_driver_unregister(&palmtx_bat_driver);
}

module_init(palmtx_bat_init);
module_exit(palmtx_bat_exit);

MODULE_LICENSE("GPL");
MODULE_AUTHOR("Marek Vasut <marek.vasut@gmail.com>");
MODULE_DESCRIPTION("Palm T|X battery driver");
OpenPOWER on IntegriCloud