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
|
/*
* SPEAr thermal driver.
*
* Copyright (C) 2011-2012 ST Microelectronics
* Author: Vincenzo Frascino <vincenzo.frascino@st.com>
*
* This software is licensed under the terms of the GNU General Public
* License version 2, as published by the Free Software Foundation, and
* may be copied, distributed, and modified under those terms.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
*/
#include <linux/clk.h>
#include <linux/device.h>
#include <linux/err.h>
#include <linux/io.h>
#include <linux/kernel.h>
#include <linux/of.h>
#include <linux/module.h>
#include <linux/platform_device.h>
#include <linux/thermal.h>
#define MD_FACTOR 1000
/* SPEAr Thermal Sensor Dev Structure */
struct spear_thermal_dev {
/* pointer to base address of the thermal sensor */
void __iomem *thermal_base;
/* clk structure */
struct clk *clk;
/* pointer to thermal flags */
unsigned int flags;
};
static inline int thermal_get_temp(struct thermal_zone_device *thermal,
unsigned long *temp)
{
struct spear_thermal_dev *stdev = thermal->devdata;
/*
* Data are ready to be read after 628 usec from POWERDOWN signal
* (PDN) = 1
*/
*temp = (readl_relaxed(stdev->thermal_base) & 0x7F) * MD_FACTOR;
return 0;
}
static struct thermal_zone_device_ops ops = {
.get_temp = thermal_get_temp,
};
#ifdef CONFIG_PM
static int spear_thermal_suspend(struct device *dev)
{
struct platform_device *pdev = to_platform_device(dev);
struct thermal_zone_device *spear_thermal = platform_get_drvdata(pdev);
struct spear_thermal_dev *stdev = spear_thermal->devdata;
unsigned int actual_mask = 0;
/* Disable SPEAr Thermal Sensor */
actual_mask = readl_relaxed(stdev->thermal_base);
writel_relaxed(actual_mask & ~stdev->flags, stdev->thermal_base);
clk_disable(stdev->clk);
dev_info(dev, "Suspended.\n");
return 0;
}
static int spear_thermal_resume(struct device *dev)
{
struct platform_device *pdev = to_platform_device(dev);
struct thermal_zone_device *spear_thermal = platform_get_drvdata(pdev);
struct spear_thermal_dev *stdev = spear_thermal->devdata;
unsigned int actual_mask = 0;
int ret = 0;
ret = clk_enable(stdev->clk);
if (ret) {
dev_err(&pdev->dev, "Can't enable clock\n");
return ret;
}
/* Enable SPEAr Thermal Sensor */
actual_mask = readl_relaxed(stdev->thermal_base);
writel_relaxed(actual_mask | stdev->flags, stdev->thermal_base);
dev_info(dev, "Resumed.\n");
return 0;
}
#endif
static SIMPLE_DEV_PM_OPS(spear_thermal_pm_ops, spear_thermal_suspend,
spear_thermal_resume);
static int spear_thermal_probe(struct platform_device *pdev)
{
struct thermal_zone_device *spear_thermal = NULL;
struct spear_thermal_dev *stdev;
struct device_node *np = pdev->dev.of_node;
struct resource *res;
int ret = 0, val;
if (!np || !of_property_read_u32(np, "st,thermal-flags", &val)) {
dev_err(&pdev->dev, "Failed: DT Pdata not passed\n");
return -EINVAL;
}
stdev = devm_kzalloc(&pdev->dev, sizeof(*stdev), GFP_KERNEL);
if (!stdev)
return -ENOMEM;
/* Enable thermal sensor */
res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
stdev->thermal_base = devm_ioremap_resource(&pdev->dev, res);
if (IS_ERR(stdev->thermal_base))
return PTR_ERR(stdev->thermal_base);
stdev->clk = devm_clk_get(&pdev->dev, NULL);
if (IS_ERR(stdev->clk)) {
dev_err(&pdev->dev, "Can't get clock\n");
return PTR_ERR(stdev->clk);
}
ret = clk_enable(stdev->clk);
if (ret) {
dev_err(&pdev->dev, "Can't enable clock\n");
return ret;
}
stdev->flags = val;
writel_relaxed(stdev->flags, stdev->thermal_base);
spear_thermal = thermal_zone_device_register("spear_thermal", 0, 0,
stdev, &ops, NULL, 0, 0);
if (IS_ERR(spear_thermal)) {
dev_err(&pdev->dev, "thermal zone device is NULL\n");
ret = PTR_ERR(spear_thermal);
goto disable_clk;
}
platform_set_drvdata(pdev, spear_thermal);
dev_info(&spear_thermal->device, "Thermal Sensor Loaded at: 0x%p.\n",
stdev->thermal_base);
return 0;
disable_clk:
clk_disable(stdev->clk);
return ret;
}
static int spear_thermal_exit(struct platform_device *pdev)
{
unsigned int actual_mask = 0;
struct thermal_zone_device *spear_thermal = platform_get_drvdata(pdev);
struct spear_thermal_dev *stdev = spear_thermal->devdata;
thermal_zone_device_unregister(spear_thermal);
/* Disable SPEAr Thermal Sensor */
actual_mask = readl_relaxed(stdev->thermal_base);
writel_relaxed(actual_mask & ~stdev->flags, stdev->thermal_base);
clk_disable(stdev->clk);
return 0;
}
static const struct of_device_id spear_thermal_id_table[] = {
{ .compatible = "st,thermal-spear1340" },
{}
};
MODULE_DEVICE_TABLE(of, spear_thermal_id_table);
static struct platform_driver spear_thermal_driver = {
.probe = spear_thermal_probe,
.remove = spear_thermal_exit,
.driver = {
.name = "spear_thermal",
.owner = THIS_MODULE,
.pm = &spear_thermal_pm_ops,
.of_match_table = spear_thermal_id_table,
},
};
module_platform_driver(spear_thermal_driver);
MODULE_AUTHOR("Vincenzo Frascino <vincenzo.frascino@st.com>");
MODULE_DESCRIPTION("SPEAr thermal driver");
MODULE_LICENSE("GPL");
|
