lantiq: add cpu temperatur sensor driver for xrx200

Signed-off-by: Florian Eckert <[email protected]>

target/linux/lantiq/config-4.4

@@ -178,6 +178,7 @@ CONFIG_RTL8366_SMI=y
 CONFIG_SCHED_HRTICK=y
 # CONFIG_SCHED_INFO is not set
 # CONFIG_SCSI_DMA is not set
+# CONFIG_SENSORS_LTQ_CPUTEMP is not set
 # CONFIG_SERIAL_8250 is not set
 CONFIG_SERIAL_LANTIQ=y
 # CONFIG_SOC_AMAZON_SE is not set

target/linux/lantiq/patches-4.4/0302-xrx200-add-sensors-driver.patch

@@ -0,0 +1,168 @@
+--- 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 <[email protected]>
++ *
++ * 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 <[email protected]>");
++
++MODULE_DESCRIPTION("Lantiq Temperature Sensor");
++MODULE_LICENSE("GPL");

target/linux/lantiq/xrx200/config-default

@@ -5,6 +5,7 @@ CONFIG_CRC16=y
 CONFIG_CRYPTO_DEFLATE=y
 CONFIG_CRYPTO_LZO=y
 CONFIG_FIRMWARE_IN_KERNEL=y
+CONFIG_HWMON=y
 CONFIG_ICPLUS_PHY=y
 CONFIG_INPUT=y
 CONFIG_INPUT_EVDEV=y
@@ -35,6 +36,7 @@ CONFIG_RTL8306_PHY=y
 CONFIG_RTL8366S_PHY=y
 CONFIG_RTL8367B_PHY=y
 CONFIG_RTL8367_PHY=y
+CONFIG_SENSORS_LTQ_CPUTEMP=y
 CONFIG_SWCONFIG_LEDS=y
 CONFIG_UBIFS_FS=y
 CONFIG_UBIFS_FS_ADVANCED_COMPR=y