From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Return-path: From: Florian Eckert To: jdelvare@suse.com, linux@roeck-us.net, linux-hwmon@vger.kernel.org, linux-kernel@vger.kernel.org, dev@kresin.me Subject: [PATCH v2 1/2] hwmon: (ltq-cputemp) add cpu temp sensor driver Date: Mon, 21 Aug 2017 14:41:22 +0200 Message-Id: <20170821124123.17470-1-fe@dev.tdt.de> MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit List-ID: Add the lantiq cpu temperature sensor support for xrx200. Signed-off-by: Florian Eckert --- v2: - remove default in Makefile - fix spelling - removing first read delay, because temperature value is not read during boot anymore - change calculation, compiler should to the optimization - remove unnecessary initialization - use new devm_hwmon_device_register_with_info API - use module_platform_driver function The soc detection for lantiq is done with this pattern. If it sould be more generic we should change this global. drivers/hwmon/Kconfig | 7 ++ drivers/hwmon/Makefile | 1 + drivers/hwmon/ltq-cputemp.c | 175 ++++++++++++++++++++++++++++++++++++++++++++ 3 files changed, 183 insertions(+) create mode 100644 drivers/hwmon/ltq-cputemp.c diff --git a/drivers/hwmon/Kconfig b/drivers/hwmon/Kconfig index 5ef2814345ef..218332f0e913 100644 --- a/drivers/hwmon/Kconfig +++ b/drivers/hwmon/Kconfig @@ -790,6 +790,13 @@ 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 driver" + depends on LANTIQ + 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 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..21c77a125c27 --- /dev/null +++ b/drivers/hwmon/ltq-cputemp.c @@ -0,0 +1,175 @@ +/* Lantiq cpu temperature sensor driver + * + * Copyright (C) 2017 Florian Eckert + * + * 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 + */ + +#include +#include +#include +#include +#include +#include + +#include + +/* 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_read(struct device *dev, enum hwmon_sensor_types type, + u32 attr, int channel, long *temp) +{ + int value; + + switch (attr) { + case hwmon_temp_input: + /* get the temperature including one decimal place */ + value = (ltq_cgu_r32(CGU_GPHY1_CR) >> 9) & 0x01FF; + value = value * 5; + /* range -38 to +154 °C, register value zero is -38.0 °C */ + value -= 380; + /* scale temp to millidegree */ + value = value * 100; + break; + default: + return -EOPNOTSUPP; + } + + *temp = value; + return 0; +} + + +static umode_t ltq_is_visible(const void *_data, enum hwmon_sensor_types type, + u32 attr, int channel) +{ + if (type != hwmon_temp) + return 0; + + switch (attr) { + case hwmon_temp_input: + return S_IRUGO; + default: + return 0; + } +} + +static const u32 ltq_chip_config[] = { + HWMON_C_REGISTER_TZ, + 0 +}; + +static const struct hwmon_channel_info ltq_chip = { + .type = hwmon_chip, + .config = ltq_chip_config, +}; + +static const u32 ltq_temp_config[] = { + HWMON_T_INPUT, + 0 +}; + +static const struct hwmon_channel_info ltq_temp = { + .type = hwmon_temp, + .config = ltq_temp_config, +}; + +static const struct hwmon_channel_info *ltq_info[] = { + <q_chip, + <q_temp, + NULL +}; + +static const struct hwmon_ops ltq_hwmon_ops = { + .is_visible = ltq_is_visible, + .read = ltq_read, +}; + +static const struct hwmon_chip_info ltq_chip_info = { + .ops = <q_hwmon_ops, + .info = ltq_info, +}; + +static int ltq_cputemp_probe(struct platform_device *pdev) +{ + 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_info(&pdev->dev, + "CPU0", + NULL, + <q_chip_info, + NULL); + + if (IS_ERR(hwmon_dev)) { + dev_err(&pdev->dev, "Failed to register as hwmon device"); + return PTR_ERR(hwmon_dev); + } + + ltq_cputemp_enable(); + + return 0; +} + +static int ltq_cputemp_release(struct platform_device *pdev) +{ + 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", + .of_match_table = ltq_cputemp_match, + }, +}; + +int __init init_ltq_cputemp(void) +{ + return platform_driver_register(<q_cputemp_driver); +} + +void clean_ltq_cputemp(void) +{ + platform_driver_unregister(<q_cputemp_driver); +} + +module_platform_driver(ltq_cputemp_driver); + +MODULE_AUTHOR("Florian Eckert "); +MODULE_DESCRIPTION("Lantiq cpu temperature sensor driver"); +MODULE_LICENSE("GPL"); -- 2.11.0