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
|
// SPDX-License-Identifier: GPL-2.0
/*
* Battery driver for the Ingenic JZ47xx SoCs
* Copyright (c) 2019 Artur Rojek <contact@artur-rojek.eu>
*
* based on drivers/power/supply/jz4740-battery.c
*/
#include <linux/iio/consumer.h>
#include <linux/module.h>
#include <linux/of.h>
#include <linux/platform_device.h>
#include <linux/power_supply.h>
#include <linux/property.h>
struct ingenic_battery {
struct device *dev;
struct iio_channel *channel;
struct power_supply_desc desc;
struct power_supply *battery;
struct power_supply_battery_info info;
};
static int ingenic_battery_get_property(struct power_supply *psy,
enum power_supply_property psp,
union power_supply_propval *val)
{
struct ingenic_battery *bat = power_supply_get_drvdata(psy);
struct power_supply_battery_info *info = &bat->info;
int ret;
switch (psp) {
case POWER_SUPPLY_PROP_HEALTH:
ret = iio_read_channel_processed(bat->channel, &val->intval);
val->intval *= 1000;
if (val->intval < info->voltage_min_design_uv)
val->intval = POWER_SUPPLY_HEALTH_DEAD;
else if (val->intval > info->voltage_max_design_uv)
val->intval = POWER_SUPPLY_HEALTH_OVERVOLTAGE;
else
val->intval = POWER_SUPPLY_HEALTH_GOOD;
return ret;
case POWER_SUPPLY_PROP_VOLTAGE_NOW:
ret = iio_read_channel_processed(bat->channel, &val->intval);
val->intval *= 1000;
return ret;
case POWER_SUPPLY_PROP_VOLTAGE_MIN_DESIGN:
val->intval = info->voltage_min_design_uv;
return 0;
case POWER_SUPPLY_PROP_VOLTAGE_MAX_DESIGN:
val->intval = info->voltage_max_design_uv;
return 0;
default:
return -EINVAL;
};
}
/* Set the most appropriate IIO channel voltage reference scale
* based on the battery's max voltage.
*/
static int ingenic_battery_set_scale(struct ingenic_battery *bat)
{
const int *scale_raw;
int scale_len, scale_type, best_idx = -1, best_mV, max_raw, i, ret;
u64 max_mV;
ret = iio_read_max_channel_raw(bat->channel, &max_raw);
if (ret) {
dev_err(bat->dev, "Unable to read max raw channel value\n");
return ret;
}
ret = iio_read_avail_channel_attribute(bat->channel, &scale_raw,
&scale_type, &scale_len,
IIO_CHAN_INFO_SCALE);
if (ret < 0) {
dev_err(bat->dev, "Unable to read channel avail scale\n");
return ret;
}
if (ret != IIO_AVAIL_LIST || scale_type != IIO_VAL_FRACTIONAL_LOG2)
return -EINVAL;
max_mV = bat->info.voltage_max_design_uv / 1000;
for (i = 0; i < scale_len; i += 2) {
u64 scale_mV = (max_raw * scale_raw[i]) >> scale_raw[i + 1];
if (scale_mV < max_mV)
continue;
if (best_idx >= 0 && scale_mV > best_mV)
continue;
best_mV = scale_mV;
best_idx = i;
}
if (best_idx < 0) {
dev_err(bat->dev, "Unable to find matching voltage scale\n");
return -EINVAL;
}
return iio_write_channel_attribute(bat->channel,
scale_raw[best_idx],
scale_raw[best_idx + 1],
IIO_CHAN_INFO_SCALE);
}
static enum power_supply_property ingenic_battery_properties[] = {
POWER_SUPPLY_PROP_HEALTH,
POWER_SUPPLY_PROP_VOLTAGE_NOW,
POWER_SUPPLY_PROP_VOLTAGE_MIN_DESIGN,
POWER_SUPPLY_PROP_VOLTAGE_MAX_DESIGN,
};
static int ingenic_battery_probe(struct platform_device *pdev)
{
struct device *dev = &pdev->dev;
struct ingenic_battery *bat;
struct power_supply_config psy_cfg = {};
struct power_supply_desc *desc;
int ret;
bat = devm_kzalloc(dev, sizeof(*bat), GFP_KERNEL);
if (!bat)
return -ENOMEM;
bat->dev = dev;
bat->channel = devm_iio_channel_get(dev, "battery");
if (IS_ERR(bat->channel))
return PTR_ERR(bat->channel);
desc = &bat->desc;
desc->name = "jz-battery";
desc->type = POWER_SUPPLY_TYPE_BATTERY;
desc->properties = ingenic_battery_properties;
desc->num_properties = ARRAY_SIZE(ingenic_battery_properties);
desc->get_property = ingenic_battery_get_property;
psy_cfg.drv_data = bat;
psy_cfg.of_node = dev->of_node;
bat->battery = devm_power_supply_register(dev, desc, &psy_cfg);
if (IS_ERR(bat->battery)) {
dev_err(dev, "Unable to register battery\n");
return PTR_ERR(bat->battery);
}
ret = power_supply_get_battery_info(bat->battery, &bat->info);
if (ret) {
dev_err(dev, "Unable to get battery info: %d\n", ret);
return ret;
}
if (bat->info.voltage_min_design_uv < 0) {
dev_err(dev, "Unable to get voltage min design\n");
return bat->info.voltage_min_design_uv;
}
if (bat->info.voltage_max_design_uv < 0) {
dev_err(dev, "Unable to get voltage max design\n");
return bat->info.voltage_max_design_uv;
}
return ingenic_battery_set_scale(bat);
}
#ifdef CONFIG_OF
static const struct of_device_id ingenic_battery_of_match[] = {
{ .compatible = "ingenic,jz4740-battery", },
{ },
};
MODULE_DEVICE_TABLE(of, ingenic_battery_of_match);
#endif
static struct platform_driver ingenic_battery_driver = {
.driver = {
.name = "ingenic-battery",
.of_match_table = of_match_ptr(ingenic_battery_of_match),
},
.probe = ingenic_battery_probe,
};
module_platform_driver(ingenic_battery_driver);
MODULE_DESCRIPTION("Battery driver for Ingenic JZ47xx SoCs");
MODULE_AUTHOR("Artur Rojek <contact@artur-rojek.eu>");
MODULE_LICENSE("GPL");
|
