Re: [PATCH v7 2/6] thermal: sy7636a: Add thermal driver for sy7636a
From: Daniel Lezcano <hidden>
Date: 2021-08-14 11:08:50
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On 08/07/2021 13:58, Alistair Francis wrote:
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From: Lars Ivar Miljeteig <redacted> Add thermal driver to enable kernel based polling and shutdown of device for temperatures out of spec Signed-off-by: Alistair Francis <redacted> --- drivers/thermal/Kconfig | 7 ++ drivers/thermal/Makefile | 1 + drivers/thermal/sy7636a_thermal.c | 107 ++++++++++++++++++++++++++++++ 3 files changed, 115 insertions(+) create mode 100644 drivers/thermal/sy7636a_thermal.cdiff --git a/drivers/thermal/Kconfig b/drivers/thermal/Kconfig index d7f44deab5b1..7112c63d9021 100644 --- a/drivers/thermal/Kconfig +++ b/drivers/thermal/Kconfig@@ -450,6 +450,13 @@ depends on (ARCH_STI || ARCH_STM32) && OF source "drivers/thermal/st/Kconfig" endmenu +config SY7636A_THERMAL + tristate "SY7636A thermal management" + depends on MFD_SY7636A + help + Enable the sy7636a thermal driver, which supports the + temperature sensor embedded in Silabs SY7636A chip. + source "drivers/thermal/tegra/Kconfig" config GENERIC_ADC_THERMALdiff --git a/drivers/thermal/Makefile b/drivers/thermal/Makefile index 82fc3e616e54..2e1aca8a0a09 100644 --- a/drivers/thermal/Makefile +++ b/drivers/thermal/Makefile@@ -51,6 +51,7 @@ obj-$(CONFIG_DA9062_THERMAL) += da9062-thermal.o obj-y += intel/ obj-$(CONFIG_TI_SOC_THERMAL) += ti-soc-thermal/ obj-y += st/ +obj-$(CONFIG_SY7636A_THERMAL) += sy7636a_thermal.o obj-$(CONFIG_QCOM_TSENS) += qcom/ obj-y += tegra/ obj-$(CONFIG_HISI_THERMAL) += hisi_thermal.odiff --git a/drivers/thermal/sy7636a_thermal.c b/drivers/thermal/sy7636a_thermal.c new file mode 100644 index 000000000000..705a16fb1045 --- /dev/null +++ b/drivers/thermal/sy7636a_thermal.c@@ -0,0 +1,107 @@ +// SPDX-License-Identifier: GPL-2.0+ +// +// Functions to access SY3686A power management chip temperature +// +// Copyright (C) 2019 reMarkable AS - http://www.remarkable.com/ +// +// Authors: Lars Ivar Miljeteig <lars.ivar.miljeteig@remarkable.com> +// Alistair Francis <alistair@alistair23.me>
// SPDX-License-Identifier: GPL-2.0+ /* * Functions to access SY3686A power management chip temperature * ... * */
+#include <linux/module.h>
+#include <linux/platform_device.h>
+#include <linux/thermal.h>
+
+#include <linux/mfd/sy7636a.h>
+
+struct sy7636a_data {
+ struct sy7636a *sy7636a;Only regmap is used AFAICT, so storing the regmap pointer is enough and the structure is not needed neither the code associated with it.
+ struct thermal_zone_device *thermal_zone_dev;
This field is only used to check the return code of the thermal_zone_device_register function. It can be local to the function below.
+};
+
+static int sy7636a_get_temp(void *arg, int *res)
+{
+ unsigned int reg_val, mode_ctr;Is it possible the sensor returns negative values ?
+ int ret;
+ struct sy7636a_data *data = arg;
+ bool isVoltageActive;
+ ret = regmap_read(data->sy7636a->regmap,
+ SY7636A_REG_OPERATION_MODE_CRL, &mode_ctr);
+ if (ret)
+ return ret;
+
+ isVoltageActive = mode_ctr & SY7636A_OPERATION_MODE_CRL_ONOFF;
+
+ if (!isVoltageActive) {
+ ret = regmap_write(data->sy7636a->regmap,
+ SY7636A_REG_OPERATION_MODE_CRL,
+ mode_ctr | SY7636A_OPERATION_MODE_CRL_ONOFF);What is this conditional block ? Please add a comment to explain why these 'isVoltageActive' test are needed.
+ if (ret)
+ return ret;
+ }
+
+ ret = regmap_read(data->sy7636a->regmap,
+ SY7636A_REG_TERMISTOR_READOUT, ®_val);
+ if (ret)
+ return ret;
+
+ if (!isVoltageActive) {
+ ret = regmap_write(data->sy7636a->regmap,
+ SY7636A_REG_OPERATION_MODE_CRL,
+ mode_ctr);
+ if (ret)
+ return ret;
+ }
+
+ *res = *((signed char*)®_val);Please revisit this.
+ *res *= 1000;
+
+ return ret;
+}
+
+static const struct thermal_zone_of_device_ops ops = {
+ .get_temp = sy7636a_get_temp,
+};
+
+static int sy7636a_thermal_probe(struct platform_device *pdev)
+{
+ struct sy7636a *sy7636a = dev_get_drvdata(pdev->dev.parent);
+ struct sy7636a_data *data;
+
+ if (!sy7636a)
+ return -EPROBE_DEFER;
+
+ data = devm_kzalloc(&pdev->dev, sizeof(struct sy7636a_data), GFP_KERNEL);
+ if (!data)
+ return -ENOMEM;
+
+ platform_set_drvdata(pdev, data);
+
+ data->sy7636a = sy7636a;
+ data->thermal_zone_dev = devm_thermal_zone_of_sensor_register(
+ pdev->dev.parent,
+ 0,
+ data,
+ &ops);
+
+ return PTR_ERR_OR_ZERO(data->thermal_zone_dev);
+}
+
+static const struct platform_device_id sy7636a_thermal_id_table[] = {
+ { "sy7636a-thermal", },
+ { }
+};
+MODULE_DEVICE_TABLE(platform, sy7636a_thermal_id_table);
+
+static struct platform_driver sy7636a_thermal_driver = {
+ .driver = {
+ .name = "sy7636a-thermal",
+ },
+ .probe = sy7636a_thermal_probe,
+ .id_table = sy7636a_thermal_id_table,
+};
+module_platform_driver(sy7636a_thermal_driver);
+
+MODULE_AUTHOR("Lars Ivar Miljeteig [off-list ref]");
+MODULE_DESCRIPTION("SY7636A thermal driver");
+MODULE_LICENSE("GPL v2");-- <http://www.linaro.org/> Linaro.org │ Open source software for ARM SoCs Follow Linaro: <http://www.facebook.com/pages/Linaro> Facebook | <http://twitter.com/#!/linaroorg> Twitter | <http://www.linaro.org/linaro-blog/> Blog