openwrt/target/linux/lantiq/patches-4.4/0302-xrx200-add-sensors-driver.patch
Florian Eckert 828e25e325 lantiq: add cpu temperatur sensor driver for xrx200
Signed-off-by: Florian Eckert <Eckert.Florian@googlemail.com>
2016-08-03 15:30:13 +02:00

169 lines
4.3 KiB
Diff

--- 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");