On 08/07/2021 13:58, Alistair Francis wrote: > From: Lars Ivar Miljeteig <lars.ivar.miljeteig@xxxxxxxxxxxxx> > > Add thermal driver to enable kernel based polling > and shutdown of device for temperatures out of spec > > Signed-off-by: Alistair Francis <alistair@xxxxxxxxxxxxx> > --- > 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.c > > diff --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_THERMAL > diff --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.o > diff --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@xxxxxxxxxxxxxx> > +// Alistair Francis <alistair@xxxxxxxxxxxxx> // 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 <lars.ivar.miljeteig@xxxxxxxxxxxxxx>"); > +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
