summaryrefslogtreecommitdiffstats
path: root/target/linux/lantiq/patches-4.4/0302-xrx200-add-sensors-driver.patch
blob: 628e476a77bf179c6611fcca45322ae34990c2e1 (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
--- a/drivers/hwmon/Makefile
+++ b/drivers/hwmon/Makefile
@@ -107,6 +107,7 @@ obj-$(CONFIG_SENSORS_LTC4222)	+= ltc4222
 obj-$(CONFIG_SENSORS_LTC4245)	+= ltc4245.o
 obj-$(CONFIG_SENSORS_LTC4260)	+= ltc4260.o
 obj-$(CONFIG_SENSORS_LTC4261)	+= ltc4261.o
+obj-$(CONFIG_SENSORS_LTQ_CPUTEMP) += ltq-cputemp.o
 obj-$(CONFIG_SENSORS_MAX1111)	+= max1111.o
 obj-$(CONFIG_SENSORS_MAX16065)	+= max16065.o
 obj-$(CONFIG_SENSORS_MAX1619)	+= max1619.o
--- a/drivers/hwmon/Kconfig
+++ b/drivers/hwmon/Kconfig
@@ -762,6 +762,14 @@ config SENSORS_LTC4261
 	  This driver can also be built as a module. If so, the module will
 	  be called ltc4261.
 
+config SENSORS_LTQ_CPUTEMP
+	bool "Lantiq CPU temperature sensor"
+	depends on LANTIQ
+	default n
+	help
+	  If you say yes here you get support for the temperature
+	  sensor inside your CPU.
+
 config SENSORS_MAX1111
 	tristate "Maxim MAX1111 Serial 8-bit ADC chip and compatibles"
 	depends on SPI_MASTER
--- /dev/null
+++ b/drivers/hwmon/ltq-cputemp.c
@@ -0,0 +1,138 @@
+/* Lantiq CPU Temperatur sensor driver for xrx200
+ *
+ * Copyright (C) 2016 Florian Eckert <feckert@tdt.de>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version
+ *
+ * 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
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, see <http://www.gnu.org/licenses/>
+ */
+
+#include <linux/module.h>
+#include <linux/init.h>
+#include <linux/of_device.h>
+#include <linux/hwmon.h>
+#include <linux/hwmon-sysfs.h>
+
+#include <lantiq_soc.h>
+
+/* gphy1 configuration register contains cpu temperature */
+#define CGU_GPHY1_CR   0x0040
+#define CGU_TEMP_PD    BIT(19)
+
+static void ltq_cputemp_enable(void)
+{
+	ltq_cgu_w32(ltq_cgu_r32(CGU_GPHY1_CR) | CGU_TEMP_PD, CGU_GPHY1_CR);
+}
+
+static void ltq_cputemp_disable(void)
+{
+	ltq_cgu_w32(ltq_cgu_r32(CGU_GPHY1_CR) & ~CGU_TEMP_PD, CGU_GPHY1_CR);
+}
+
+static int ltq_cputemp_read(void)
+{
+	/* Shift 9 for register alignment and 1 to divide value by 2 */
+	return (ltq_cgu_r32(CGU_GPHY1_CR) >> 10) & 0xFF;
+}
+
+static ssize_t show_cputemp(struct device *dev,
+			struct device_attribute *attr, char *buf)
+{
+	int value;
+
+	value = ltq_cputemp_read();
+	/* scale temp to millidegree */
+	value = value * 1000;
+
+	return sprintf(buf, "%d\n", value);
+}
+
+static DEVICE_ATTR(temp1_input, S_IRUGO, show_cputemp, NULL);
+
+static struct attribute *ltq_cputemp_attrs[] = {
+	&dev_attr_temp1_input.attr,
+	NULL
+};
+
+ATTRIBUTE_GROUPS(ltq_cputemp);
+
+static int ltq_cputemp_probe(struct platform_device *pdev)
+{
+	int value = 0;
+	int ret;
+	struct device *hwmon_dev;
+
+	hwmon_dev = devm_hwmon_device_register_with_groups(&pdev->dev,
+							"CPU0",
+							NULL,
+							ltq_cputemp_groups);
+
+	if (IS_ERR(hwmon_dev)) {
+		dev_err(&pdev->dev, "Failed to register as hwmon device");
+		ret = PTR_ERR(hwmon_dev);
+		goto error_hwmon;
+	}
+
+	ltq_cputemp_enable();
+	value = ltq_cputemp_read();
+	dev_info(&pdev->dev, "Current CPU die temperature: %d °C", value);
+
+	return 0;
+
+error_hwmon:
+	return ret;
+}
+
+static int ltq_cputemp_release(struct platform_device *pdev)
+{
+	hwmon_device_unregister(&pdev->dev);
+	ltq_cputemp_disable();
+	return 0;
+}
+
+const struct of_device_id ltq_cputemp_match[] = {
+	{ .compatible = "lantiq,cputemp" },
+	{},
+};
+MODULE_DEVICE_TABLE(of, ltq_cputemp_match);
+
+static struct platform_driver ltq_cputemp_driver = {
+	.probe = ltq_cputemp_probe,
+	.remove = ltq_cputemp_release,
+	.driver = {
+		.name = "ltq-cputemp",
+		.owner = THIS_MODULE,
+		.of_match_table = ltq_cputemp_match,
+	},
+};
+
+int __init init_ltq_cputemp(void)
+{
+	int ret;
+
+	ret = platform_driver_register(&ltq_cputemp_driver);
+	return ret;
+}
+
+void clean_ltq_cputemp(void)
+{
+	platform_driver_unregister(&ltq_cputemp_driver);
+	return;
+}
+
+module_init(init_ltq_cputemp);
+module_exit(clean_ltq_cputemp);
+
+MODULE_AUTHOR("Florian Eckert <feckert@tdt.de>");
+
+MODULE_DESCRIPTION("Lantiq Temperature Sensor");
+MODULE_LICENSE("GPL");