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
|
// SPDX-License-Identifier: GPL-2.0+
/*
* GPD Pocket fan controller driver
*
* Copyright (C) 2017 Hans de Goede <hdegoede@redhat.com>
*/
#include <linux/acpi.h>
#include <linux/gpio/consumer.h>
#include <linux/module.h>
#include <linux/moduleparam.h>
#include <linux/platform_device.h>
#include <linux/power_supply.h>
#include <linux/thermal.h>
#include <linux/workqueue.h>
#define MAX_SPEED 3
static int temp_limits[3] = { 55000, 60000, 65000 };
module_param_array(temp_limits, int, NULL, 0444);
MODULE_PARM_DESC(temp_limits,
"Milli-celcius values above which the fan speed increases");
static int hysteresis = 3000;
module_param(hysteresis, int, 0444);
MODULE_PARM_DESC(hysteresis,
"Hysteresis in milli-celcius before lowering the fan speed");
static int speed_on_ac = 2;
module_param(speed_on_ac, int, 0444);
MODULE_PARM_DESC(speed_on_ac,
"minimum fan speed to allow when system is powered by AC");
struct gpd_pocket_fan_data {
struct device *dev;
struct thermal_zone_device *dts0;
struct thermal_zone_device *dts1;
struct gpio_desc *gpio0;
struct gpio_desc *gpio1;
struct delayed_work work;
int last_speed;
};
static void gpd_pocket_fan_set_speed(struct gpd_pocket_fan_data *fan, int speed)
{
if (speed == fan->last_speed)
return;
gpiod_direction_output(fan->gpio0, !!(speed & 1));
gpiod_direction_output(fan->gpio1, !!(speed & 2));
fan->last_speed = speed;
}
static int gpd_pocket_fan_min_speed(void)
{
if (power_supply_is_system_supplied())
return speed_on_ac;
else
return 0;
}
static void gpd_pocket_fan_worker(struct work_struct *work)
{
struct gpd_pocket_fan_data *fan =
container_of(work, struct gpd_pocket_fan_data, work.work);
int t0, t1, temp, speed, min_speed, i;
if (thermal_zone_get_temp(fan->dts0, &t0) ||
thermal_zone_get_temp(fan->dts1, &t1)) {
dev_warn(fan->dev, "Error getting temperature\n");
speed = MAX_SPEED;
goto set_speed;
}
temp = max(t0, t1);
speed = fan->last_speed;
min_speed = gpd_pocket_fan_min_speed();
/* Determine minimum speed */
for (i = min_speed; i < ARRAY_SIZE(temp_limits); i++) {
if (temp < temp_limits[i])
break;
}
if (speed < i)
speed = i;
/* Use hysteresis before lowering speed again */
for (i = min_speed; i < ARRAY_SIZE(temp_limits); i++) {
if (temp <= (temp_limits[i] - hysteresis))
break;
}
if (speed > i)
speed = i;
if (fan->last_speed <= 0 && speed)
speed = MAX_SPEED; /* kick start motor */
set_speed:
gpd_pocket_fan_set_speed(fan, speed);
/* When mostly idle (low temp/speed), slow down the poll interval. */
queue_delayed_work(system_wq, &fan->work,
msecs_to_jiffies(4000 / (speed + 1)));
}
static void gpd_pocket_fan_force_update(struct gpd_pocket_fan_data *fan)
{
fan->last_speed = -1;
mod_delayed_work(system_wq, &fan->work, 0);
}
static int gpd_pocket_fan_probe(struct platform_device *pdev)
{
struct gpd_pocket_fan_data *fan;
int i;
for (i = 0; i < ARRAY_SIZE(temp_limits); i++) {
if (temp_limits[i] < 40000 || temp_limits[i] > 70000) {
dev_err(&pdev->dev, "Invalid temp-limit %d (must be between 40000 and 70000)\n",
temp_limits[i]);
return -EINVAL;
}
}
if (hysteresis < 1000 || hysteresis > 10000) {
dev_err(&pdev->dev, "Invalid hysteresis %d (must be between 1000 and 10000)\n",
hysteresis);
return -EINVAL;
}
if (speed_on_ac < 0 || speed_on_ac > MAX_SPEED) {
dev_err(&pdev->dev, "Invalid speed_on_ac %d (must be between 0 and 3)\n",
speed_on_ac);
return -EINVAL;
}
fan = devm_kzalloc(&pdev->dev, sizeof(*fan), GFP_KERNEL);
if (!fan)
return -ENOMEM;
fan->dev = &pdev->dev;
INIT_DELAYED_WORK(&fan->work, gpd_pocket_fan_worker);
/* Note this returns a "weak" reference which we don't need to free */
fan->dts0 = thermal_zone_get_zone_by_name("soc_dts0");
if (IS_ERR(fan->dts0))
return -EPROBE_DEFER;
fan->dts1 = thermal_zone_get_zone_by_name("soc_dts1");
if (IS_ERR(fan->dts1))
return -EPROBE_DEFER;
fan->gpio0 = devm_gpiod_get_index(fan->dev, NULL, 0, GPIOD_ASIS);
if (IS_ERR(fan->gpio0))
return PTR_ERR(fan->gpio0);
fan->gpio1 = devm_gpiod_get_index(fan->dev, NULL, 1, GPIOD_ASIS);
if (IS_ERR(fan->gpio1))
return PTR_ERR(fan->gpio1);
gpd_pocket_fan_force_update(fan);
platform_set_drvdata(pdev, fan);
return 0;
}
static int gpd_pocket_fan_remove(struct platform_device *pdev)
{
struct gpd_pocket_fan_data *fan = platform_get_drvdata(pdev);
cancel_delayed_work_sync(&fan->work);
return 0;
}
#ifdef CONFIG_PM_SLEEP
static int gpd_pocket_fan_suspend(struct device *dev)
{
struct gpd_pocket_fan_data *fan = dev_get_drvdata(dev);
cancel_delayed_work_sync(&fan->work);
gpd_pocket_fan_set_speed(fan, gpd_pocket_fan_min_speed());
return 0;
}
static int gpd_pocket_fan_resume(struct device *dev)
{
struct gpd_pocket_fan_data *fan = dev_get_drvdata(dev);
gpd_pocket_fan_force_update(fan);
return 0;
}
#endif
static SIMPLE_DEV_PM_OPS(gpd_pocket_fan_pm_ops,
gpd_pocket_fan_suspend,
gpd_pocket_fan_resume);
static struct acpi_device_id gpd_pocket_fan_acpi_match[] = {
{ "FAN02501" },
{},
};
MODULE_DEVICE_TABLE(acpi, gpd_pocket_fan_acpi_match);
static struct platform_driver gpd_pocket_fan_driver = {
.probe = gpd_pocket_fan_probe,
.remove = gpd_pocket_fan_remove,
.driver = {
.name = "gpd_pocket_fan",
.acpi_match_table = gpd_pocket_fan_acpi_match,
.pm = &gpd_pocket_fan_pm_ops,
},
};
module_platform_driver(gpd_pocket_fan_driver);
MODULE_AUTHOR("Hans de Goede <hdegoede@redhat.com");
MODULE_DESCRIPTION("GPD pocket fan driver");
MODULE_LICENSE("GPL");
|
