Re: [PATCH v4 01/11] thermal: sun8i: add thermal driver for h6

Ondřej Jirman
2019-06-24T12:07:38Z

Hello Yangtao,

On Sun, Jun 23, 2019 at 12:41:56PM -0400, Yangtao Li wrote:
> This patch adds the support for allwinner thermal sensor, within
> allwinner SoC. It will register sensors for thermal framework
> and use device tree to bind cooling device.
>
> Signed-off-by: Yangtao Li <tiny.windzz@gmail.com>
> ---
> MAINTAINERS | 7 +
> drivers/thermal/Kconfig | 14 ++
> drivers/thermal/Makefile | 1 +
> drivers/thermal/sun8i_thermal.c | 405 ++++++++++++++++++++++++++++++++
> 4 files changed, 427 insertions(+)
> create mode 100644 drivers/thermal/sun8i_thermal.c
>
> diff --git a/MAINTAINERS b/MAINTAINERS
> index 36a84614d6c3..67e7fcfaded2 100644
> --- a/MAINTAINERS
> +++ b/MAINTAINERS
> @@ -674,6 +674,13 @@ L: linux-crypto@vger.kernel.org
> S: Maintained
> F: drivers/crypto/sunxi-ss/
>
> +ALLWINNER THERMAL DRIVER
> +M: Yangtao Li <tiny.windzz@gmail.com>
> +L: linux-pm@vger.kernel.org
> +S: Maintained
> +F: Documentation/devicetree/bindings/thermal/sun8i-thermal.yaml
> +F: drivers/thermal/sun8i_thermal.c
> +
> ALLWINNER VPU DRIVER
> M: Maxime Ripard <maxime.ripard@bootlin.com>
> M: Paul Kocialkowski <paul.kocialkowski@bootlin.com>
> diff --git a/drivers/thermal/Kconfig b/drivers/thermal/Kconfig
> index 9966364a6deb..f8b73b32b92d 100644
> --- a/drivers/thermal/Kconfig
> +++ b/drivers/thermal/Kconfig
> @@ -262,6 +262,20 @@ config SPEAR_THERMAL
> Enable this to plug the SPEAr thermal sensor driver into the Linux
> thermal framework.
>
> +config SUN8I_THERMAL
> + tristate "Allwinner sun8i thermal driver"
> + depends on ARCH_SUNXI || COMPILE_TEST
> + depends on HAS_IOMEM
> + depends on NVMEM
> + depends on OF
> + depends on RESET_CONTROLLER
> + help
> + Support for the sun8i thermal sensor driver into the Linux thermal
> + framework.
> +
> + To compile this driver as a module, choose M here: the
> + module will be called sun8i-thermal.
> +
> config ROCKCHIP_THERMAL
> tristate "Rockchip thermal driver"
> depends on ARCH_ROCKCHIP || COMPILE_TEST
> diff --git a/drivers/thermal/Makefile b/drivers/thermal/Makefile
> index 74a37c7f847a..fa6f8b206281 100644
> --- a/drivers/thermal/Makefile
> +++ b/drivers/thermal/Makefile
> @@ -31,6 +31,7 @@ thermal_sys-$(CONFIG_DEVFREQ_THERMAL) += devfreq_cooling.o
> obj-y += broadcom/
> obj-$(CONFIG_THERMAL_MMIO) += thermal_mmio.o
> obj-$(CONFIG_SPEAR_THERMAL) += spear_thermal.o
> +obj-$(CONFIG_SUN8I_THERMAL) += sun8i_thermal.o
> obj-$(CONFIG_ROCKCHIP_THERMAL) += rockchip_thermal.o
> obj-$(CONFIG_RCAR_THERMAL) += rcar_thermal.o
> obj-$(CONFIG_RCAR_GEN3_THERMAL) += rcar_gen3_thermal.o
> diff --git a/drivers/thermal/sun8i_thermal.c b/drivers/thermal/sun8i_thermal.c
> new file mode 100644
> index 000000000000..d6918c62682b
> --- /dev/null
> +++ b/drivers/thermal/sun8i_thermal.c
> @@ -0,0 +1,405 @@
> +// SPDX-License-Identifier: GPL-2.0
> +/*
> + * Thermal sensor driver for Allwinner SOC
> + * Copyright (C) 2019 Yangtao Li
> + *
> + * Based on the work of Icenowy Zheng <icenowy@aosc.io>
> + * Based on the work of Ondrej Jirman <megous@megous.com>
> + * Based on the work of Josef Gajdusek <atx@atx.name>
> + */
> +
> +#include <linux/clk.h>
> +#include <linux/device.h>
> +#include <linux/interrupt.h>
> +#include <linux/module.h>
> +#include <linux/nvmem-consumer.h>
> +#include <linux/of_device.h>
> +#include <linux/platform_device.h>
> +#include <linux/regmap.h>
> +#include <linux/reset.h>
> +#include <linux/slab.h>
> +#include <linux/thermal.h>
> +
> +#define MAX_SENSOR_NUM 4
> +
> +#define SUN50I_H6_SENSOR_NUM 2
> +#define SUN50I_H6_OFFSET -2794
> +#define SUN50I_H6_SCALE -67
> +
> +#define FT_TEMP_MASK GENMASK(11, 0)
> +#define TEMP_CALIB_MASK GENMASK(11, 0)
> +#define TEMP_TO_REG 672
> +#define CALIBRATE_DEFAULT 0x800
> +
> +#define SUN50I_THS_CTRL0 0x00
> +#define SUN50I_H6_THS_ENABLE 0x04
> +#define SUN50I_H6_THS_PC 0x08
> +#define SUN50I_H6_THS_DIC 0x10
> +#define SUN50I_H6_THS_DIS 0x20
> +#define SUN50I_H6_THS_MFC 0x30
> +#define SUN50I_H6_THS_TEMP_CALIB 0xa0
> +#define SUN50I_H6_THS_TEMP_DATA 0xc0
> +
> +#define SUN50I_THS_CTRL0_T_ACQ(x) ((GENMASK(15, 0) & (x)) << 16)
> +#define SUN50I_THS_FILTER_EN BIT(2)
> +#define SUN50I_THS_FILTER_TYPE(x) (GENMASK(1, 0) & (x))
> +#define SUN50I_H6_THS_PC_TEMP_PERIOD(x) ((GENMASK(19, 0) & (x)) << 12)
> +#define SUN50I_H6_THS_DATA_IRQ_STS(x) BIT(x)
> +
> +/* millidegree celsius */
> +#define SUN50I_H6_FT_DEVIATION 7000
> +
> +struct ths_device;
> +
> +struct tsensor {
> + struct ths_device *tmdev;
> + struct thermal_zone_device *tzd;
> + int id;
> +};
> +
> +struct ths_device {
> + struct device *dev;
> + struct regmap *regmap;
> + struct reset_control *reset;
> + struct clk *bus_clk;
> + struct tsensor sensor[MAX_SENSOR_NUM];
> +};
> +
> +/* Temp Unit: millidegree Celsius */
> +static int sun8i_ths_reg2temp(struct ths_device *tmdev,
> + int reg)
> +{
> + return (reg + SUN50I_H6_OFFSET) * SUN50I_H6_SCALE;
> +}
> +
> +static int sun8i_ths_get_temp(void *data, int *temp)
> +{
> + struct tsensor *s = data;
> + struct ths_device *tmdev = s->tmdev;
> + int val;
> +
> + regmap_read(tmdev->regmap, SUN50I_H6_THS_TEMP_DATA +
> + 0x4 * s->id, &val);
> +
> + /* ths have no data yet */
> + if (!val)
> + return -EBUSY;

You should return -EAGAIN here to avoid the warning (failed to read out thermal
zone (%d)) if you believe this error is temporary.

regards,
o.

> + *temp = sun8i_ths_reg2temp(tmdev, val);
> + /*
> + * XX - According to the original sdk, there are some platforms(rarely)
> + * that add a fixed offset value after calculating the temperature
> + * value. We can't simply put it on the formula for calculating the
> + * temperature above, because the formula for calculating the
> + * temperature above is also used when the sensor is calibrated. If
> + * do this, the correct calibration formula is hard to know.
> + */
> + *temp += SUN50I_H6_FT_DEVIATION;
> +
> + return 0;
> +}
> +
> +static const struct thermal_zone_of_device_ops ths_ops = {
> + .get_temp = sun8i_ths_get_temp,
> +};
> +
> +static const struct regmap_config config = {
> + .reg_bits = 32,
> + .val_bits = 32,
> + .reg_stride = 4,
> + .fast_io = true,
> +};
> +
> +static irqreturn_t sun50i_h6_irq_thread(int irq, void *data)
> +{
> + struct ths_device *tmdev = data;
> + int i, state;
> +
> + regmap_read(tmdev->regmap, SUN50I_H6_THS_DIS, &state);
> +
> + for (i = 0; i < SUN50I_H6_SENSOR_NUM; i++) {
> +
> + if (state & SUN50I_H6_THS_DATA_IRQ_STS(i)) {
> + /* clear data irq pending */
> + regmap_write(tmdev->regmap, SUN50I_H6_THS_DIS,
> + SUN50I_H6_THS_DATA_IRQ_STS(i));
> +
> + thermal_zone_device_update(tmdev->sensor[i].tzd,
> + THERMAL_EVENT_UNSPECIFIED);
> + }
> + }
> +
> + return IRQ_HANDLED;
> +}
> +
> +static int sun50i_ths_calibrate(struct ths_device *tmdev)
> +{
> + struct nvmem_cell *calcell;
> + struct device *dev = tmdev->dev;
> + u16 *caldata;
> + size_t callen;
> + int ft_temp;
> + int i, ret = 0;
> +
> + calcell = devm_nvmem_cell_get(dev, "calib");
> + if (IS_ERR(calcell)) {
> + if (PTR_ERR(calcell) == -EPROBE_DEFER)
> + return -EPROBE_DEFER;
> + /*
> + * Even if the external calibration data stored in sid is
> + * not accessible, the THS hardware can still work, although
> + * the data won't be so accurate.
> + *
> + * The default value of calibration register is 0x800 for
> + * every sensor, and the calibration value is usually 0x7xx
> + * or 0x8xx, so they won't be away from the default value
> + * for a lot.
> + *
> + * So here we do not return error if the calibartion data is
> + * not available, except the probe needs deferring.
> + */
> + goto out;
> + }
> +
> + caldata = nvmem_cell_read(calcell, &callen);
> + if (IS_ERR(caldata)) {
> + ret = PTR_ERR(caldata);
> + goto out;
> + }
> +
> + if (!caldata[0] || callen < 2 + 2 * SUN50I_H6_SENSOR_NUM) {
> + ret = -EINVAL;
> + goto out_free;
> + }
> +
> + /*
> + * efuse layout:
> + *
> + * 0 11 16 32
> + * +-------+-------+-------+
> + * |temp| |sensor0|sensor1|
> + * +-------+-------+-------+
> + *
> + * The calibration data on the H6 is the ambient temperature and
> + * sensor values that are filled during the factory test stage.
> + *
> + * The unit of stored FT temperature is 0.1 degreee celusis.
> + * Through the stored ambient temperature and the data read
> + * by the sensor, after a certain calculation, the calibration
> + * value to be compensated can be obtained.
> + */
> + ft_temp = caldata[0] & FT_TEMP_MASK;
> +
> + for (i = 0; i < SUN50I_H6_SENSOR_NUM; i++) {
> + int reg = (int)caldata[i + 1];
> + int sensor_temp = sun8i_ths_reg2temp(tmdev, reg);
> + int delta, cdata, calib_offest;
> +
> + /*
> + * To calculate the calibration value:
> + *
> + * X(in Celsius) = Ts - ft_temp
> + * delta = X * 10000 / TEMP_TO_REG
> + * cdata = CALIBRATE_DEFAULT - delta
> + *
> + * cdata: calibration value
> + */
> + delta = (sensor_temp - ft_temp * 100) * 10 / TEMP_TO_REG;
> + cdata = CALIBRATE_DEFAULT - delta;
> + if (cdata & ~TEMP_CALIB_MASK) {
> + /*
> + * Calibration value more than 12-bit, but calibration
> + * register is 12-bit. In this case, ths hardware can
> + * still work without calibration, although the data
> + * won't be so accurate.
> + */
> + dev_warn(dev, "sensor%d is not calibrated.\n", i);
> +
> + continue;
> + }
> +
> + calib_offest = SUN50I_H6_THS_TEMP_CALIB + (i / 2) * 0x4;
> +
> + if (i % 2) {
> + int val;
> +
> + regmap_read(tmdev->regmap, calib_offest, &val);
> + val = (val & TEMP_CALIB_MASK) | (cdata << 16);
> + regmap_write(tmdev->regmap, calib_offest, val);
> + } else {
> + regmap_write(tmdev->regmap, calib_offest, cdata);
> + }
> + }
> +
> +out_free:
> + kfree(caldata);
> +out:
> + return ret;
> +}
> +
> +static int sun8i_ths_resource_init(struct ths_device *tmdev)
> +{
> + struct device *dev = tmdev->dev;
> + struct platform_device *pdev = to_platform_device(dev);
> + struct resource *mem;
> + void __iomem *base;
> + int ret;
> +
> + mem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
> + base = devm_ioremap_resource(dev, mem);
> + if (IS_ERR(base))
> + return PTR_ERR(base);
> +
> + tmdev->regmap = devm_regmap_init_mmio(dev, base, &config);
> + if (IS_ERR(tmdev->regmap))
> + return PTR_ERR(tmdev->regmap);
> +
> + tmdev->reset = devm_reset_control_get(dev, 0);
> + if (IS_ERR(tmdev->reset))
> + return PTR_ERR(tmdev->reset);
> +
> + tmdev->bus_clk = devm_clk_get(&pdev->dev, "bus");
> + if (IS_ERR(tmdev->bus_clk))
> + return PTR_ERR(tmdev->bus_clk);
> +
> + ret = reset_control_deassert(tmdev->reset);
> + if (ret)
> + return ret;
> +
> + ret = clk_prepare_enable(tmdev->bus_clk);
> + if (ret)
> + goto assert_reset;
> +
> + ret = sun50i_ths_calibrate(tmdev);
> + if (ret)
> + goto bus_disable;
> +
> + return 0;
> +
> +bus_disable:
> + clk_disable_unprepare(tmdev->bus_clk);
> +assert_reset:
> + reset_control_assert(tmdev->reset);
> +
> + return ret;
> +}
> +
> +static int sun50i_thermal_init(struct ths_device *tmdev)
> +{
> + int val;
> +
> + /*
> + * clkin = 24MHz
> + * T acquire = clkin / (x + 1)
> + * = 20us
> + */
> + regmap_write(tmdev->regmap, SUN50I_THS_CTRL0,
> + SUN50I_THS_CTRL0_T_ACQ(479));
> + /* average over 4 samples */
> + regmap_write(tmdev->regmap, SUN50I_H6_THS_MFC,
> + SUN50I_THS_FILTER_EN |
> + SUN50I_THS_FILTER_TYPE(1));
> + /* period = (x + 1) * 4096 / clkin; ~10ms */
> + regmap_write(tmdev->regmap, SUN50I_H6_THS_PC,
> + SUN50I_H6_THS_PC_TEMP_PERIOD(58));
> + /* enable sensor */
> + val = GENMASK(SUN50I_H6_SENSOR_NUM - 1, 0);
> + regmap_write(tmdev->regmap, SUN50I_H6_THS_ENABLE, val);
> + /* thermal data interrupt enable */
> + val = GENMASK(SUN50I_H6_SENSOR_NUM - 1, 0);
> + regmap_write(tmdev->regmap, SUN50I_H6_THS_DIC, val);
> +
> + return 0;
> +}
> +
> +static int sun8i_ths_register(struct ths_device *tmdev)
> +{
> + struct thermal_zone_device *tzd;
> + int i;
> +
> + for (i = 0; i < SUN50I_H6_SENSOR_NUM; i++) {
> + tmdev->sensor[i].tmdev = tmdev;
> + tmdev->sensor[i].id = i;
> + tmdev->sensor[i].tzd =
> + devm_thermal_zone_of_sensor_register(tmdev->dev,
> + i,
> + &tmdev->sensor[i],
> + &ths_ops);
> + if (IS_ERR(tmdev->sensor[i].tzd))
> + return PTR_ERR(tzd);
> + }
> +
> + return 0;
> +}
> +
> +static int sun8i_ths_probe(struct platform_device *pdev)
> +{
> + struct ths_device *tmdev;
> + struct device *dev = &pdev->dev;
> + int ret, irq;
> +
> + tmdev = devm_kzalloc(dev, sizeof(*tmdev), GFP_KERNEL);
> + if (!tmdev)
> + return -ENOMEM;
> +
> + tmdev->dev = dev;
> + platform_set_drvdata(pdev, tmdev);
> +
> + ret = sun8i_ths_resource_init(tmdev);
> + if (ret)
> + return ret;
> +
> + irq = platform_get_irq(pdev, 0);
> + if (irq < 0)
> + return irq;
> +
> + ret = sun50i_thermal_init(tmdev);
> + if (ret)
> + return ret;
> +
> + ret = sun8i_ths_register(tmdev);
> + if (ret)
> + return ret;
> +
> + /*
> + * Avoid entering the interrupt handler, the thermal device is not
> + * registered yet, we deffer the registration of the interrupt to
> + * the end.
> + */
> + ret = devm_request_threaded_irq(dev, irq, NULL,
> + sun50i_h6_irq_thread,
> + IRQF_ONESHOT, "ths", tmdev);
> + if (ret)
> + return ret;
> +
> + return ret;
> +}
> +
> +static int sun8i_ths_remove(struct platform_device *pdev)
> +{
> + struct ths_device *tmdev = platform_get_drvdata(pdev);
> +
> + clk_disable_unprepare(tmdev->bus_clk);
> + reset_control_assert(tmdev->reset);
> +
> + return 0;
> +}
> +
> +static const struct of_device_id of_ths_match[] = {
> + { .compatible = "allwinner,sun50i-h6-ths"},
> + { /* sentinel */ },
> +};
> +MODULE_DEVICE_TABLE(of, of_ths_match);
> +
> +static struct platform_driver ths_driver = {
> + .probe = sun8i_ths_probe,
> + .remove = sun8i_ths_remove,
> + .driver = {
> + .name = "sun8i-thermal",
> + .of_match_table = of_ths_match,
> + },
> +};
> +module_platform_driver(ths_driver);
> +
> +MODULE_DESCRIPTION("Thermal sensor driver for Allwinner SOC");
> +MODULE_LICENSE("GPL v2");
> --
> 2.17.1
>
>
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