Re: [PATCH v7 1/2] thermal: Add thermal driver for Sunplus SP7021

From: 郭力豪
Date: Thu Apr 14 2022 - 09:49:49 EST

Hi

>> +
>> + cell = nvmem_cell_get(dev, "calib");
>> + if (IS_ERR(cell))
>> + return PTR_ERR(cell);
>> +
>> + otp_v = nvmem_cell_read(cell, &otp_l);
>> + nvmem_cell_put(cell);

>See my previous comments in v4, this is wrong. Move the nvmem_cell_put()
>after FIELD_PREP() ... below where otp_v is no longer used.

> + if (otp_l < 3)
> + return -EINVAL;

>Please replace '3' by a macro

>Why this check is needed by the way ? Sounds like only 0 and 1 indexes
>are used here.

you mean the following?

sp_data->otp_temp0 = nvmem_cell_read(cell, &otp_l);
nvmem_cell_put(cell);

> +static const struct of_device_id of_sp7021_thermal_ids[] = {
> + { .compatible = "sunplus,sp7021-thermal" },
> + { /* sentinel */ }
> +};
> +MODULE_DEVICE_TABLE(of, of_sp7021_thermal_ids);
> +
> +static struct platform_driver sp7021_thermal_driver = {
> + .probe = sp7021_thermal_probe,

>and .remove ?

If the remove function just returns 0; must it still exist?

Li-hao Kuo <lhjeff911@xxxxxxxxx> 於 2022年4月11日 週一 下午4:52寫道：
>
> Add thermal driver for Sunplus SP7021.
>
> Signed-off-by: Li-hao Kuo <lhjeff911@xxxxxxxxx>
> ---
> Changes in v7:
> - Modify yaml file.
>
> MAINTAINERS | 6 ++
> drivers/thermal/Kconfig | 10 +++
> drivers/thermal/Makefile | 1 +
> drivers/thermal/sunplus_thermal.c | 139 ++++++++++++++++++++++++++++++++++++++
> 4 files changed, 156 insertions(+)
> create mode 100644 drivers/thermal/sunplus_thermal.c
>
> diff --git a/MAINTAINERS b/MAINTAINERS
> index 61d9f11..307570c 100644
> --- a/MAINTAINERS
> +++ b/MAINTAINERS
> @@ -18885,6 +18885,12 @@ S: Maintained
> F: Documentation/devicetree/bindings/spi/spi-sunplus-sp7021.yaml
> F: drivers/spi/spi-sunplus-sp7021.c
>
> +SUNPLUS THERMAL DRIVER
> +M: Li-hao Kuo <lhjeff911@xxxxxxxxx>
> +L: linux-pm@xxxxxxxxxxxxxxx
> +S: Maintained
> +F: drivers/thermal/sunplus_thermal.c
> +
> SUNPLUS UART DRIVER
> M: Hammer Hsieh <hammerh0314@xxxxxxxxx>
> S: Maintained
> diff --git a/drivers/thermal/Kconfig b/drivers/thermal/Kconfig
> index e37691e..66316c3 100644
> --- a/drivers/thermal/Kconfig
> +++ b/drivers/thermal/Kconfig
> @@ -502,4 +502,14 @@ config KHADAS_MCU_FAN_THERMAL
> If you say yes here you get support for the FAN controlled
> by the Microcontroller found on the Khadas VIM boards.
>
> +config SUNPLUS_THERMAL
> + tristate "Sunplus thermal drivers"
> + depends on SOC_SP7021 || COMPILE_TEST
> + help
> + This the Sunplus SP7021 thermal driver, which supports the primitive
> + temperature sensor embedded in Sunplus SP7021 SoC.
> +
> + If you have a Sunplus SP7021 platform say Y here and enable this option
> + to have support for thermal management
> +
> endif
> diff --git a/drivers/thermal/Makefile b/drivers/thermal/Makefile
> index f0c36a1..38a76f9 100644
> --- a/drivers/thermal/Makefile
> +++ b/drivers/thermal/Makefile
> @@ -61,3 +61,4 @@ obj-$(CONFIG_UNIPHIER_THERMAL) += uniphier_thermal.o
> obj-$(CONFIG_AMLOGIC_THERMAL) += amlogic_thermal.o
> obj-$(CONFIG_SPRD_THERMAL) += sprd_thermal.o
> obj-$(CONFIG_KHADAS_MCU_FAN_THERMAL) += khadas_mcu_fan.o
> +obj-$(CONFIG_SUNPLUS_THERMAL) += sunplus_thermal.o
> diff --git a/drivers/thermal/sunplus_thermal.c b/drivers/thermal/sunplus_thermal.c
> new file mode 100644
> index 0000000..9a9b348
> --- /dev/null
> +++ b/drivers/thermal/sunplus_thermal.c
> @@ -0,0 +1,139 @@
> +// SPDX-License-Identifier: GPL-2.0-only
> +/*
> + * Copyright (c) Sunplus Inc.
> + * Author: Li-hao Kuo <lhjeff911@xxxxxxxxx>
> + */
> +
> +#include <linux/bitfield.h>
> +#include <linux/clk.h>
> +#include <linux/delay.h>
> +#include <linux/io.h>
> +#include <linux/module.h>
> +#include <linux/nvmem-consumer.h>
> +#include <linux/platform_device.h>
> +#include <linux/reset.h>
> +#include <linux/thermal.h>
> +
> +#define DISABLE_THERMAL (BIT(31) | BIT(15))
> +#define ENABLE_THERMAL BIT(31)
> +#define SP_THERMAL_MASK GENMASK(10, 0)
> +#define SP_TCODE_HIGH_MASK GENMASK(10, 8)
> +#define SP_TCODE_LOW_MASK GENMASK(7, 0)
> +
> +#define TEMP_RATE 608
> +#define TEMP_BASE 3500
> +#define TEMP_OTP_BASE 1518
> +
> +#define SP_THERMAL_CTL0_REG 0x0000
> +#define SP_THERMAL_STS0_REG 0x0030
> +
> +/* common data structures */
> +struct sp_thermal_data {
> + struct thermal_zone_device *pcb_tz;
> + struct platform_device *pdev;
> + enum thermal_device_mode mode;
> + void __iomem *regs;
> + int otp_temp0;
> + u32 id;
> +};
> +
> +static int sp7021_get_otp_temp_coef(struct sp_thermal_data *sp_data, struct device *dev)
> +{
> + struct nvmem_cell *cell;
> + ssize_t otp_l;
> + char *otp_v;
> +
> + cell = nvmem_cell_get(dev, "calib");
> + if (IS_ERR(cell))
> + return PTR_ERR(cell);
> +
> + otp_v = nvmem_cell_read(cell, &otp_l);
> + nvmem_cell_put(cell);
> +
> + if (otp_l < 3)
> + return -EINVAL;
> + sp_data->otp_temp0 = FIELD_PREP(SP_TCODE_LOW_MASK, otp_v[0]) |
> + FIELD_PREP(SP_TCODE_HIGH_MASK, otp_v[1]);
> + if (sp_data->otp_temp0 == 0)
> + sp_data->otp_temp0 = TEMP_OTP_BASE;
> + return 0;
> +}
> +
> +/*
> + *When remanufacturing, the 35 degree T_CODE will be read and stored in nvcell.
> + *TEMP_RATE is the SP7021 temperature slope.
> + *T_CODE : 11 digits in total
> + */
> +
> +static int sp_thermal_get_sensor_temp(void *data, int *temp)
> +{
> + struct sp_thermal_data *sp_data = data;
> + int t_code;
> +
> + t_code = readl(sp_data->regs + SP_THERMAL_STS0_REG);
> + t_code = FIELD_GET(SP_THERMAL_MASK, t_code);
> + *temp = ((sp_data->otp_temp0 - t_code) * 10000 / TEMP_RATE) + TEMP_BASE;
> + *temp *= 10;
> + return 0;
> +}
> +
> +static const struct thermal_zone_of_device_ops sp_of_thermal_ops = {
> + .get_temp = sp_thermal_get_sensor_temp,
> +};
> +
> +static int sp_thermal_register_sensor(struct platform_device *pdev,
> + struct sp_thermal_data *data, int index)
> +{
> + data->id = index;
> + data->pcb_tz = devm_thermal_zone_of_sensor_register(&pdev->dev,
> + data->id,
> + data, &sp_of_thermal_ops);
> + if (IS_ERR_OR_NULL(data->pcb_tz))
> + return PTR_ERR(data->pcb_tz);
> + return 0;
> +}
> +
> +static int sp7021_thermal_probe(struct platform_device *pdev)
> +{
> + struct sp_thermal_data *sp_data;
> + struct resource *res;
> + int ret;
> +
> + sp_data = devm_kzalloc(&pdev->dev, sizeof(*sp_data), GFP_KERNEL);
> + if (!sp_data)
> + return -ENOMEM;
> +
> + sp_data->regs = devm_platform_ioremap_resource(pdev, 0);
> + if (IS_ERR(sp_data->regs)) {
> + dev_err(&pdev->dev, "resource get fail\n");
> + return PTR_ERR(sp_data->regs);
> + }
> +
> + writel(ENABLE_THERMAL, sp_data->regs + SP_THERMAL_CTL0_REG);
> +
> + platform_set_drvdata(pdev, sp_data);
> + ret = sp7021_get_otp_temp_coef(sp_data, &pdev->dev);
> + if (ret)
> + return ret;
> + ret = sp_thermal_register_sensor(pdev, sp_data, 0);
> + return ret;
> +}
> +
> +static const struct of_device_id of_sp7021_thermal_ids[] = {
> + { .compatible = "sunplus,sp7021-thermal" },
> + { /* sentinel */ }
> +};
> +MODULE_DEVICE_TABLE(of, of_sp7021_thermal_ids);
> +
> +static struct platform_driver sp7021_thermal_driver = {
> + .probe = sp7021_thermal_probe,
> + .driver = {
> + .name = "sp7021-thermal",
> + .of_match_table = of_sp7021_thermal_ids,
> + },
> +};
> +module_platform_driver(sp7021_thermal_driver);
> +
> +MODULE_AUTHOR("Li-hao Kuo <lhjeff911@xxxxxxxxx>");
> +MODULE_DESCRIPTION("Thermal driver for SP7021 SoC");
> +MODULE_LICENSE("GPL");
> --
> 2.7.4
>