hwmon: (ltq-cputemp) add cpu temp sensor for xrx200
Subsystems (2)
PATCH 1/2 hwmon: (ltq-cputemp) add cpu temp sensor for xrx200
Add the lantiq cpu temperature sensor support for xrx200.
Signed-off-by Florian Eckert <[email protected]>
--- drivers/hwmon/Kconfig | 8 +++ drivers/hwmon/Makefile | 1 + drivers/hwmon/ltq-cputemp.c | 155 ++++++++++++++++++++++++++++++++++++++++++++ 3 files changed, 164 insertions(+) create mode 100644 drivers/hwmon/ltq-cputemp.c
drivers/hwmon/Kconfig +8 -0
@@ -790,6 +790,14 @@ 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 for xrx200" + depends on LANTIQ + default n + help + If you say yes here you get support for the temperature + sensor inside your xrx200 CPU. + config SENSORS_MAX1111 tristate "Maxim MAX1111 Serial 8-bit ADC chip and compatibles" depends on SPI_MASTER
drivers/hwmon/Makefile +1 -0
@@ -110,6 +110,7 @@ obj-$(CONFIG_SENSORS_LTC4222) += ltc4222.o obj-$(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
drivers/hwmon/ltq-cputemp.c new file +155 -0
155 lines not on this page · raw message
Signature · 1 line
2.11.0
PATCH 2/2 hwmon: (ltq-cputemp) add devicetree bindings documentation
Document the devicetree bindings for the ltq-cputemp
Signed-off-by Florian Eckert <[email protected]>
--- Documentation/devicetree/bindings/hwmon/ltq-cputemp.txt | 10 ++++++++++ 1 file changed, 10 insertions(+) create mode 100644 Documentation/devicetree/bindings/hwmon/ltq-cputemp.txt
Documentation/devicetree/bindings/hwmon/ltq-cputemp.txt new file +10 -0
@@ -0,0 +1,10 @@ +Lantiq cpu temperatur sensor for xrx200 + +Requires node properties: +- "compatible" value : + "lantiq,cputemp" + +Example: + cputemp@0 { + compatible = "lantiq,cputemp"; + };
Signature · 1 line
2.11.0
Guenter Roeck
maintainerQuoted 15 lines · Florian Eckert
Add the lantiq cpu temperature sensor support for xrx200.
Signed-off-by Florian Eckert <[email protected]>--- drivers/hwmon/Kconfig | 8 +++ drivers/hwmon/Makefile | 1 + drivers/hwmon/ltq-cputemp.c | 155 ++++++++++++++++++++++++++++++++++++++++++++ 3 files changed, 164 insertions(+)create mode 100644
drivers/hwmon/ltq-cputemp.cdrivers/hwmon/Kconfig +0
-0
drivers/hwmon/Kconfig config SENSORS_LTC4261 · line 796
Quoted 7 lines
drivers/hwmon/Kconfig +4
-0@@ -790,6 +790,14 @@ 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 for xrx200" + depends on LANTIQ + default n
n is already the default. No need to specify it.
Quoted 51 lines
drivers/hwmon/Kconfig +4
-0+ help + If you say yes here you get support for the temperature + sensor inside your xrx200 CPU. + config SENSORS_MAX1111 tristate "Maxim MAX1111 Serial 8-bit ADC chip and compatibles" depends on SPI_MASTERdrivers/hwmon/Makefile +1
-0@@ -110,6 +110,7 @@ obj-$(CONFIG_SENSORS_LTC4222) += ltc4222.o obj-$(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.odrivers/hwmon/ltq-cputemp.c new file +26
-0@@ -0,0 +1,155 @@ +/* Lantiq cpu temperature sensor driver for xrx200 +* +* Copyright (C) 2017 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/delay.h> +#include <linux/of_device.h> +#include <linux/hwmon.h> +#include <linux/hwmon-sysfs.h> + +#include <lantiq_soc.h>
drivers/hwmon/ltq-cputemp.c line 36
Quoted 10 lines
drivers/hwmon/ltq-cputemp.c new file +10
-0+ +/* 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 ); + +/* wait a short moment to let the SoC get the first temperatur value */
temperature
drivers/hwmon/ltq-cputemp.c line 37
Quoted 1 line
drivers/hwmon/ltq-cputemp.c new file +1
-0+mdelay (100 );
An active delay during boot doesn't sound like a good idea to me. It might be better to mark the time and add an msleep() into the read function if called too early.
Quoted 5 lines
drivers/hwmon/ltq-cputemp.c new file +5
-0+} + +static void ltq_cputemp_disable (void ) +{ +ltq_cgu_w32 (ltq_cgu_r32 (CGU_GPHY1_CR ) & ~CGU_TEMP_PD ,CGU_GPHY1_CR );
drivers/hwmon/ltq-cputemp.c line 52
Quoted 10 lines
drivers/hwmon/ltq-cputemp.c new file +10
-0+} + +static int ltq_cputemp_read (void ) +{ +int value; + +/* get the temperature including one decimal place */ + value = (ltq_cgu_r32 (CGU_GPHY1_CR ) >>9 ) &0x01FF ; + value = (value <<2 ) + value; +
Can you just multiply times 5 and leave the optimization to the compiler ? This would be much easier to understand.
Quoted 20 lines
drivers/hwmon/ltq-cputemp.c new file +20
-0+/* range -38 to +154 °C, register value zero is -38.0 °C */ + value -=380 ; + +return value; +} + +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 *100 ; + +return sprintf (buf,"%d\n" , value); +} + +static DEVICE_ATTR(temp1_input, S_IRUGO, show_cputemp, NULL); +
drivers/hwmon/ltq-cputemp.c line 82
Quoted 10 lines
drivers/hwmon/ltq-cputemp.c new file +10
-0+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 ;
Unnecessary initialization.
drivers/hwmon/ltq-cputemp.c line 89
Quoted 7 lines
drivers/hwmon/ltq-cputemp.c new file +7
-0+int ret; +struct device *hwmon_dev; + +/* available on vr9 v1.2 SoCs only */ +if (ltq_soc_type () !=SOC_TYPE_VR9_2 ) +return -ENODEV ; +
Any chance to make this a bit more generic ? It is quite likely that later SOC revisions will support it as well, meaning we'll have to repeatedly touch the driver.
drivers/hwmon/ltq-cputemp.c line 93
Quoted 4 lines
drivers/hwmon/ltq-cputemp.c new file +4
-0+ hwmon_dev =devm_hwmon_device_register_with_groups (&pdev->dev, +"CPU0" , +NULL , + ltq_cputemp_groups);
Please consider using devm_hwmon_device_register_with_info() instead. This driver looks like an excellent fit for the new API.
drivers/hwmon/ltq-cputemp.c line 98
Quoted 5 lines
drivers/hwmon/ltq-cputemp.c new file +5
-0+ +if (IS_ERR (hwmon_dev)) { +dev_err (&pdev->dev,"Failed to register as hwmon device" ); + ret =PTR_ERR (hwmon_dev); + goto error_hwmon;
Unnecessary goto. Just return.
drivers/hwmon/ltq-cputemp.c line 106
Quoted 8 lines
drivers/hwmon/ltq-cputemp.c new file +8
-0+ } + +ltq_cputemp_enable (); + value =ltq_cputemp_read (); +dev_info (&pdev->dev, +"Current CPU die temperature: %d.%d °C" , + value /10 , + value %10 );
Highly unusual, even more so since it requires an active 100 ms delay during boot. Please drop.
drivers/hwmon/ltq-cputemp.c line 116
Quoted 10 lines
drivers/hwmon/ltq-cputemp.c new file +10
-0+ +return 0 ; + +error_hwmon: +return ret; +} + +static int ltq_cputemp_release (struct platform_device *pdev) +{ +hwmon_device_unregister (&pdev->dev);
This is done automatically (or don't the the devm function to register it). Besides, it takes the hwmon device as argument.
Quoted 6 lines
drivers/hwmon/ltq-cputemp.c new file +6
-0+ltq_cputemp_disable (); +return 0 ; +} + +const struct of_device_id ltq_cputemp_match[] = { + { .compatible ="lantiq,cputemp" },
drivers/hwmon/ltq-cputemp.c line 132
Quoted 10 lines
drivers/hwmon/ltq-cputemp.c new file +10
-0+ {}, +}; +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 ,
AFAIK this is no longer necessary.
drivers/hwmon/ltq-cputemp.c line 142
Quoted 10 lines
drivers/hwmon/ltq-cputemp.c new file +10
-0+ .of_match_table = ltq_cputemp_match, + }, +}; + +int __init init_ltq_cputemp (void ) +{ +int ret; + + ret =platform_driver_register (<q_cputemp_driver); +return ret;
Unnecessary variable. I am quite sure there is a template for this code, though.
drivers/hwmon/ltq-cputemp.c line 151
Quoted 9 lines
drivers/hwmon/ltq-cputemp.c new file +9
-0+} + +void clean_ltq_cputemp (void ) +{ +platform_driver_unregister (<q_cputemp_driver); +} + +module_init (init_ltq_cputemp); +module_exit (clean_ltq_cputemp);
module_platform_driver ?
Quoted 5 lines
drivers/hwmon/ltq-cputemp.c new file +4
-0+ +MODULE_AUTHOR ("Florian Eckert <[email protected]>" ); +MODULE_DESCRIPTION ("Lantiq Temperature Sensor" ); +MODULE_LICENSE ("GPL" );