| Message ID | 20170817125311.24679-1-fe@dev.tdt.de (mailing list archive) |
|---|---|
| State | Superseded |
| Headers | show |
On 08/17/2017 05:53 AM, Florian Eckert wrote: > Add the lantiq cpu temperature sensor support for xrx200. > > Signed-off-by: Florian Eckert <fe@dev.tdt.de> > --- > 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 > > diff --git a/drivers/hwmon/Kconfig b/drivers/hwmon/Kconfig > index 5ef2814345ef..ed3f5e1d10cc 100644 > --- a/drivers/hwmon/Kconfig > +++ b/drivers/hwmon/Kconfig > @@ -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. > + 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 > diff --git a/drivers/hwmon/Makefile b/drivers/hwmon/Makefile > index d4641a9f16c1..c84d9784be98 100644 > --- a/drivers/hwmon/Makefile > +++ b/drivers/hwmon/Makefile > @@ -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 > diff --git a/drivers/hwmon/ltq-cputemp.c b/drivers/hwmon/ltq-cputemp.c > new file mode 100644 > index 000000000000..a6f820533164 > --- /dev/null > +++ b/drivers/hwmon/ltq-cputemp.c > @@ -0,0 +1,155 @@ > +/* Lantiq cpu temperature sensor driver for xrx200 > + * > + * Copyright (C) 2017 Florian Eckert <fe@dev.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/delay.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); > + > + /* wait a short moment to let the SoC get the first temperatur value */ temperature > + 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. > +} > + > +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) > +{ > + 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. > + /* 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); > + > +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. > + 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. > + 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. > + > + 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. > + } > + > + 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. > + > + 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. > + 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, AFAIK this is no longer necessary. > + .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. > +} > + > +void clean_ltq_cputemp(void) > +{ > + platform_driver_unregister(<q_cputemp_driver); > +} > + > +module_init(init_ltq_cputemp); > +module_exit(clean_ltq_cputemp); module_platform_driver ? > + > +MODULE_AUTHOR("Florian Eckert <fe@dev.tdt.de>"); > +MODULE_DESCRIPTION("Lantiq Temperature Sensor"); > +MODULE_LICENSE("GPL"); > -- To unsubscribe from this list: send the line "unsubscribe linux-hwmon" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
diff --git a/drivers/hwmon/Kconfig b/drivers/hwmon/Kconfig index 5ef2814345ef..ed3f5e1d10cc 100644 --- a/drivers/hwmon/Kconfig +++ b/drivers/hwmon/Kconfig @@ -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 diff --git a/drivers/hwmon/Makefile b/drivers/hwmon/Makefile index d4641a9f16c1..c84d9784be98 100644 --- a/drivers/hwmon/Makefile +++ b/drivers/hwmon/Makefile @@ -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 diff --git a/drivers/hwmon/ltq-cputemp.c b/drivers/hwmon/ltq-cputemp.c new file mode 100644 index 000000000000..a6f820533164 --- /dev/null +++ b/drivers/hwmon/ltq-cputemp.c @@ -0,0 +1,155 @@ +/* Lantiq cpu temperature sensor driver for xrx200 + * + * Copyright (C) 2017 Florian Eckert <fe@dev.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/delay.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); + + /* wait a short moment to let the SoC get the first temperatur value */ + mdelay(100); +} + +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) +{ + int value; + + /* get the temperature including one decimal place */ + value = (ltq_cgu_r32(CGU_GPHY1_CR) >> 9) & 0x01FF; + value = (value << 2) + value; + + /* 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); + +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; + + /* available on vr9 v1.2 SoCs only */ + if (ltq_soc_type() != SOC_TYPE_VR9_2) + return -ENODEV; + + 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.%d °C", + value / 10, + value % 10); + + 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(<q_cputemp_driver); + return ret; +} + +void clean_ltq_cputemp(void) +{ + platform_driver_unregister(<q_cputemp_driver); +} + +module_init(init_ltq_cputemp); +module_exit(clean_ltq_cputemp); + +MODULE_AUTHOR("Florian Eckert <fe@dev.tdt.de>"); +MODULE_DESCRIPTION("Lantiq Temperature Sensor"); +MODULE_LICENSE("GPL");
Add the lantiq cpu temperature sensor support for xrx200. Signed-off-by: Florian Eckert <fe@dev.tdt.de> --- 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