[PATCH] thermal: Add support for Sunxi THS on the Allwinner H3

Chen-Yu Tsai wens at csie.org
Wed Nov 18 19:44:44 PST 2015


On Thu, Nov 19, 2015 at 4:51 AM, Josef Gajdusek <atx at atx.name> wrote:
> This patch adds support for the Sunxi thermal sensor on the Allwinner H3.
> Also adds declaration of the H3 THS clock to clk-sunxi.c ignoring the
> dividers as they are not continuous (clk-divider.c cannot be used as it
> does not support setting an enable bit).

That is not right. See below.

> Should be easily extendable for the A33/A83T/... as they have similar but
> not completely identical sensors.
>
> Signed-off-by: Josef Gajdusek <atx at atx.name>
> ---
>  Documentation/devicetree/bindings/clock/sunxi.txt  |   1 +
>  .../devicetree/bindings/thermal/sunxi-ths.txt      |  24 ++
>  arch/arm/boot/dts/sun8i-h3.dtsi                    |  27 +++
>  drivers/clk/sunxi/clk-sunxi.c                      |  16 ++
>  drivers/thermal/Kconfig                            |   7 +
>  drivers/thermal/Makefile                           |   1 +
>  drivers/thermal/sunxi_ths.c                        | 263 +++++++++++++++++++++

Thanks for working on this.

This patch should be split into 5 patches: clock binding, clock driver,
THS binding, THS driver, and DTS updates.

>  7 files changed, 339 insertions(+)
>  create mode 100644 Documentation/devicetree/bindings/thermal/sunxi-ths.txt
>  create mode 100644 drivers/thermal/sunxi_ths.c
>
> diff --git a/Documentation/devicetree/bindings/clock/sunxi.txt b/Documentation/devicetree/bindings/clock/sunxi.txt
> index 23e7bce..6d63b35 100644
> --- a/Documentation/devicetree/bindings/clock/sunxi.txt
> +++ b/Documentation/devicetree/bindings/clock/sunxi.txt
> @@ -73,6 +73,7 @@ Required properties:
>         "allwinner,sun8i-h3-usb-clk" - for usb gates + resets on H3
>         "allwinner,sun9i-a80-usb-mod-clk" - for usb gates + resets on A80
>         "allwinner,sun9i-a80-usb-phy-clk" - for usb phy gates + resets on A80
> +       "allwinner,sun8i-h3-ths-clk" - for THS on H3
>
>  Required properties for all clocks:
>  - reg : shall be the control register address for the clock.
> diff --git a/Documentation/devicetree/bindings/thermal/sunxi-ths.txt b/Documentation/devicetree/bindings/thermal/sunxi-ths.txt
> new file mode 100644
> index 0000000..75c9211
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/thermal/sunxi-ths.txt
> @@ -0,0 +1,24 @@
> +* sunxi THS
> +
> +Required properties:
> +- compatible : "allwinner,sun8i-h3-ths"
> +- reg : Address range of the thermal registers and location of the calibration
> +        value

The latter is part of the Security ID (efuses) block, for which we have
Documentation/devicetree/bindings/nvmem/allwinner,sunxi-sid.txt.
Please use a phandle to the security id block instead.

See Documentation/devicetree/bindings/nvmem/nvmem.txt for the generic
nvmem bindings.

> +- resets : Must contain an entry for each entry in reset-names.
> +           see ../reset/reset.txt for details
> +- reset-names : Must include the name "ahb"
> +- clocks : Must contain an entry for each entry in clock-names.
> +- clock-names : Must contain "ahb" for the bus gate and "ths" for the THS
> +  clock
> +
> +Example:
> +ths: ths at 01c25000 {
> +       #thermal-sensor-cells = <0>;
> +       compatible = "allwinner,sun8i-h3-ths";
> +       reg = <0x01c25000 0x88>, <0x01c14234 0x4>;
> +       interrupts = <GIC_SPI 63 IRQ_TYPE_LEVEL_HIGH>;
> +       resets = <&bus_rst 136>;
> +       reset-names = "ahb";
> +       clocks = <&bus_gates 72>, <&ths_clk>;
> +       clock-names = "ahb", "ths";
> +};
> diff --git a/arch/arm/boot/dts/sun8i-h3.dtsi b/arch/arm/boot/dts/sun8i-h3.dtsi
> index 0faa38a..b82881d 100644
> --- a/arch/arm/boot/dts/sun8i-h3.dtsi
> +++ b/arch/arm/boot/dts/sun8i-h3.dtsi
> @@ -77,6 +77,14 @@
>                 };
>         };
>
> +       thermal-zones {
> +               cpu_thermal: cpu_thermal {
> +                       polling-delay-passive = <1000>;
> +                       polling-delay = <5000>;
> +                       thermal-sensors = <&ths 0>;
> +               };
> +       };
> +
>         timer {
>                 compatible = "arm,armv7-timer";
>                 interrupts = <GIC_PPI 13 (GIC_CPU_MASK_SIMPLE(4) | IRQ_TYPE_LEVEL_LOW)>,
> @@ -236,6 +244,14 @@
>                                         "ahb1_ephy", "ahb1_dbg";
>                 };
>
> +               ths_clk: clk at 01c20074 {
> +                       #clock-cells = <0>;
> +                       compatible = "allwinner,sun8i-h3-ths-clk";
> +                       reg = <0x01c20074 0x4>;
> +                       clocks = <&osc24M>;
> +                       clock-output-names = "ths";
> +               };
> +
>                 mmc0_clk: clk at 01c20088 {
>                         #clock-cells = <1>;
>                         compatible = "allwinner,sun4i-a10-mmc-clk";
> @@ -522,6 +538,17 @@
>                         interrupts = <GIC_SPI 25 IRQ_TYPE_LEVEL_HIGH>;
>                 };
>
> +               ths: ths at 01c25000 {
> +                       #thermal-sensor-cells = <0>;
> +                       compatible = "allwinner,sun8i-h3-ths";
> +                       reg = <0x01c25000 0x88>, <0x01c14234 0x4>;
> +                       interrupts = <GIC_SPI 63 IRQ_TYPE_LEVEL_HIGH>;
> +                       resets = <&bus_rst 104>;
> +                       reset-names = "ahb";
> +                       clocks = <&bus_gates 72>, <&ths_clk>;
> +                       clock-names = "ahb", "ths";
> +               };
> +
>                 uart0: serial at 01c28000 {
>                         compatible = "snps,dw-apb-uart";
>                         reg = <0x01c28000 0x400>;
> diff --git a/drivers/clk/sunxi/clk-sunxi.c b/drivers/clk/sunxi/clk-sunxi.c
> index 6293c65..637401a 100644
> --- a/drivers/clk/sunxi/clk-sunxi.c
> +++ b/drivers/clk/sunxi/clk-sunxi.c
> @@ -604,6 +604,13 @@ static void sun7i_a20_get_out_factors(u32 *freq, u32 parent_rate,
>         *p = calcp;
>  }
>
> +static void sun8i_h3_get_ths_factors(u32 *freq, u32 parent_rate,
> +                                     u8 *n, u8 *k, u8 *m, u8 *p)
> +{
> +       /* Ignore the dividers as they are not continuous */
> +       *freq = parent_rate;
> +}
> +
>  /**
>   * sunxi_factors_clk_setup() - Setup function for factor clocks
>   */
> @@ -668,6 +675,8 @@ static struct clk_factors_config sun4i_apb1_config = {
>         .pwidth = 2,
>  };
>
> +static struct clk_factors_config sun8i_h3_ths_config = {};
> +
>  /* user manual says "n" but it's really "p" */
>  static struct clk_factors_config sun7i_a20_out_config = {
>         .mshift = 8,
> @@ -734,6 +743,12 @@ static const struct factors_data sun7i_a20_out_data __initconst = {
>         .getter = sun7i_a20_get_out_factors,
>  };
>
> +static const struct factors_data sun8i_h3_ths_data __initconst = {
> +       .enable = 31,
> +       .table = &sun8i_h3_ths_config,
> +       .getter = sun8i_h3_get_ths_factors,
> +};
> +
>  static struct clk * __init sunxi_factors_clk_setup(struct device_node *node,
>                                                    const struct factors_data *data)
>  {
> @@ -1127,6 +1142,7 @@ static const struct of_device_id clk_factors_match[] __initconst = {
>         {.compatible = "allwinner,sun5i-a13-ahb-clk", .data = &sun5i_a13_ahb_data,},
>         {.compatible = "allwinner,sun4i-a10-apb1-clk", .data = &sun4i_apb1_data,},
>         {.compatible = "allwinner,sun7i-a20-out-clk", .data = &sun7i_a20_out_data,},
> +       {.compatible = "allwinner,sun8i-h3-ths-clk", .data = &sun8i_h3_ths_data,},

Please don't add clocks to this list. We are breaking them out into individual
CLK_OF_DECLARE statements so they work better with the CCF's clock dependency
probe ordering stuff.

Instead, do a standalone driver under drivers/clk/sunxi, like

    drivers/clk/sunxi/clk-a23-ths.c

Note we normally name a module/driver/compatible based on the first
SoC it appeared
in. Since the dividers aren't contiguous, you should use a divider table. And it
also has a clock gate, so you should probably use composite clk to
bring together
the gate and divider into a single clk.

See https://github.com/wens/linux/blob/sun4i-ve-clocks/drivers/clk/sunxi/clk-a10-ve.c
for a similar driver. You can ignore the reset control bits. This
driver hasn't been
submitted.

>         {}
>  };
>
> diff --git a/drivers/thermal/Kconfig b/drivers/thermal/Kconfig
> index c463c89..0111d4d 100644
> --- a/drivers/thermal/Kconfig
> +++ b/drivers/thermal/Kconfig
> @@ -365,6 +365,13 @@ config INTEL_PCH_THERMAL
>           Thermal reporting device will provide temperature reading,
>           programmable trip points and other information.
>
> +config SUNXI_THS
> +       tristate "Sunxi THS driver"
> +       depends on ARCH_SUNXI
> +       depends on OF
> +       help
> +         Enable this to support thermal reporting on some newer Allwinner SoC.

Nit: SoCs, plural.

> +
>  menu "Texas Instruments thermal drivers"
>  depends on ARCH_HAS_BANDGAP || COMPILE_TEST
>  source "drivers/thermal/ti-soc-thermal/Kconfig"
> diff --git a/drivers/thermal/Makefile b/drivers/thermal/Makefile
> index cfae6a6..3a25e3c 100644
> --- a/drivers/thermal/Makefile
> +++ b/drivers/thermal/Makefile
> @@ -48,3 +48,4 @@ obj-$(CONFIG_INTEL_PCH_THERMAL)       += intel_pch_thermal.o
>  obj-$(CONFIG_ST_THERMAL)       += st/
>  obj-$(CONFIG_TEGRA_SOCTHERM)   += tegra_soctherm.o
>  obj-$(CONFIG_HISI_THERMAL)     += hisi_thermal.o
> +obj-$(CONFIG_SUNXI_THS)                += sunxi_ths.o

Hmm, is there supposed to be some sort of ordering here?

> diff --git a/drivers/thermal/sunxi_ths.c b/drivers/thermal/sunxi_ths.c
> new file mode 100644
> index 0000000..650cd39
> --- /dev/null
> +++ b/drivers/thermal/sunxi_ths.c
> @@ -0,0 +1,263 @@
> +/*
> + * Sunxi THS driver
> + *
> + * Copyright (C) 2015 Josef Gajdusek
> + *
> + * This software is licensed under the terms of the GNU General Public
> + * License version 2, as published by the Free Software Foundation, and
> + * may be copied, distributed, and modified under those terms.
> + *
> + * 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.
> + *
> + */
> +
> +#include <linux/clk-provider.h>
> +#include <linux/clk.h>
> +#include <linux/delay.h>
> +#include <linux/interrupt.h>
> +#include <linux/io.h>
> +#include <linux/irq.h>
> +#include <linux/module.h>
> +#include <linux/of_device.h>
> +#include <linux/platform_device.h>
> +#include <linux/printk.h>
> +#include <linux/reset.h>
> +#include <linux/thermal.h>
> +
> +#define THS_H3_CTRL0                   0x00
> +#define THS_H3_CTRL1                   0x04
> +#define THS_H3_CDAT                            0x14
> +#define THS_H3_CTRL2                   0x40
> +#define THS_H3_INT_CTRL                        0x44
> +#define THS_H3_STAT                            0x48
> +#define THS_H3_ALARM_CTRL              0x50
> +#define THS_H3_SHUTDOWN_CTRL   0x60
> +#define THS_H3_FILTER                  0x70
> +#define THS_H3_CDATA                   0x74
> +#define THS_H3_DATA                            0x80
> +
> +#define THS_H3_CTRL0_SENSOR_ACQ0               0
> +
> +#define THS_H3_CTRL1_ADC_CALI_EN               17
> +#define THS_H3_CTRL1_OP_BIAS                   20
> +
> +#define THS_H3_CTRL2_SENSE_EN                  0
> +#define THS_H3_CTRL2_SENSOR_ACQ1               16
> +
> +#define THS_H3_INT_CTRL_ALARM_INT_EN   0
> +#define THS_H3_INT_CTRL_SHUT_INT_EN            4
> +#define THS_H3_INT_CTRL_DATA_IRQ_EN            8
> +#define THS_H3_INT_CTRL_THERMAL_PER            12
> +
> +#define THS_H3_STAT_ALARM_INT_STS              0
> +#define THS_H3_STAT_SHUT_INT_STS               4
> +#define THS_H3_STAT_DATA_IRQ_STS               8
> +#define THS_H3_STAT_ALARM_OFF_STS              12
> +
> +#define THS_H3_ALARM_CTRL_ALARM0_T_HYST                0
> +#define THS_H3_ALARM_CTRL_ALARM0_T_HOT         16
> +
> +#define THS_H3_SHUTDOWN_CTRL_SHUT0_T_HOT       16
> +
> +#define THS_H3_FILTER_TYPE                             0
> +#define THS_H3_FILTER_EN                               2
> +
> +struct sunxi_ths_data {
> +       struct sunxi_ths_type *type;
> +       struct reset_control *reset;
> +       struct clk *clk;
> +       struct clk *busclk;
> +       void __iomem *regs;
> +       void __iomem *calreg;
> +       struct platform_device *pdev;
> +       struct thermal_zone_device *tzd;
> +       int irq;
> +};
> +
> +struct sunxi_ths_type {
> +       int (*init)(struct sunxi_ths_data *);
> +       int (*get_temp)(struct sunxi_ths_data *, int *out);
> +};

Move this before struct sunxi_ths_data.

> +
> +static int sunxi_ths_reg_to_temperature(int32_t reg, int divisor, int minus)
> +{
> +       return minus - (reg * 1000000) / divisor;
> +}
> +
> +static int sunxi_ths_get_temp(void *_data, int *out)
> +{
> +       struct sunxi_ths_data *data = _data;
> +
> +       return data->type->get_temp(data, out);
> +}
> +
> +static int sunxi_ths_h3_init(struct sunxi_ths_data *data)
> +{
> +       if (data->calreg)
> +               writel(readl(data->calreg) & 0xfff, data->regs + THS_H3_CDATA);

Again, use the nvmem API to read out the data.

> +       /* Magical constants mostly taken from Allwinner 3.4 kernel.
> +        * Seem to work fine, though this could be configurable in DT/sysft

                                                                        sysfs

Please check the user manual for the meaning of these constants. They are
not magic. ACQ0, ACQ1, and THERMAL_PER control the time each step of
acquiring the temperature takes. The programming guideline requires
"THERMAL_PER > ACQ1 + ACQ0 + conversion time"

The hardware also has an interrupt line, which can be used to signal there's
data worth reading, or a warning threshold was exceeded.

You can also look at drivers/input/touchscreen/sun4i-ts.c, which includes
the older thermal sensor.

> +        */
> +       writel(0xff << THS_H3_CTRL0_SENSOR_ACQ0,
> +                       data->regs + THS_H3_CTRL0);
> +       writel((0x3f << THS_H3_CTRL2_SENSOR_ACQ1) | BIT(THS_H3_CTRL2_SENSE_EN),
> +                       data->regs + THS_H3_CTRL2);
> +       writel((0x390 << THS_H3_INT_CTRL_THERMAL_PER) | BIT(THS_H3_INT_CTRL_DATA_IRQ_EN),
> +                       data->regs + THS_H3_INT_CTRL);
> +       writel(BIT(THS_H3_FILTER_EN) | (0x2 << THS_H3_FILTER_TYPE),
> +                       data->regs + THS_H3_FILTER);
> +       return 0;
> +}
> +
> +static int sunxi_ths_h3_get_temp(struct sunxi_ths_data *data, int *out)
> +{
> +       *out = sunxi_ths_reg_to_temperature(readl(data->regs + THS_H3_DATA),
> +                       8253, 217000);
> +       return 0;
> +}
> +
> +static const struct thermal_zone_of_device_ops sunxi_ths_thermal_ops = {
> +       .get_temp = sunxi_ths_get_temp,
> +};
> +
> +static const struct sunxi_ths_type sunxi_ths_device_h3 = {
> +       .init = sunxi_ths_h3_init,
> +       .get_temp = sunxi_ths_h3_get_temp,
> +};
> +
> +static const struct of_device_id sunxi_ths_id_table[] = {
> +       {
> +               .compatible = "allwinner,sun8i-h3-ths",
> +               .data = &sunxi_ths_device_h3,
> +       },
> +       {
> +               /* sentinel */
> +       },
> +};
> +MODULE_DEVICE_TABLE(of, sunxi_ths_id_table);
> +
> +static int sunxi_ths_probe(struct platform_device *pdev)
> +{
> +       struct device_node *np = pdev->dev.of_node;
> +       const struct of_device_id *match;
> +       struct sunxi_ths_data *data;
> +       struct resource *res;
> +       int ret;
> +
> +       match = of_match_node(sunxi_ths_id_table, np);
> +       if (!match)
> +               return -ENXIO;
> +
> +       data =
> +               devm_kzalloc(&pdev->dev, sizeof(struct sunxi_ths_data), GFP_KERNEL);
> +       if (!data)
> +               return -ENOMEM;
> +
> +       data->type = (struct sunxi_ths_type *) match->data;
> +       data->pdev = pdev;
> +
> +       res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
> +       data->regs = devm_ioremap_resource(&pdev->dev, res);
> +       if (IS_ERR(data->regs)) {
> +               ret = PTR_ERR(data->regs);
> +               dev_err(&pdev->dev, "failed to ioremap THS registers: %d\n", ret);
> +               return ret;
> +       }
> +
> +       res = platform_get_resource(pdev, IORESOURCE_MEM, 1);
> +       data->calreg = devm_ioremap_resource(&pdev->dev, res);
> +       if (IS_ERR(data->calreg))
> +               data->calreg = NULL; /* No calibration register */

The calibration data is part of the Security ID efuse module, for which
we have an nvmem driver. Please use the nvmem API for this.

> +
> +       data->busclk = devm_clk_get(&pdev->dev, "ahb");
> +       if (IS_ERR(data->busclk)) {
> +               ret = PTR_ERR(data->busclk);
> +               dev_err(&pdev->dev, "failed to get ahb clk: %d\n", ret);
> +               return ret;
> +       }
> +
> +       data->clk = devm_clk_get(&pdev->dev, "ths");
> +       if (IS_ERR(data->clk)) {
> +               ret = PTR_ERR(data->clk);
> +               dev_err(&pdev->dev, "failed to get ths clk: %d\n", ret);
> +               return ret;
> +       }
> +
> +       data->reset = devm_reset_control_get_optional(&pdev->dev, "ahb");

Why is this optional?


Regards
ChenYu

> +       if (IS_ERR(data->reset)) {
> +               ret = PTR_ERR(data->reset);
> +               dev_err(&pdev->dev, "failed to get reset: %d\n", ret);
> +               return ret;
> +       }
> +
> +       ret = clk_prepare_enable(data->busclk);
> +       if (ret) {
> +               dev_err(&pdev->dev, "failed to enable bus clk: %d\n", ret);
> +               return ret;
> +       }
> +
> +       ret = clk_prepare_enable(data->clk);
> +       if (ret) {
> +               dev_err(&pdev->dev, "failed to enable ths clk: %d\n", ret);
> +               goto err_disable_bus;
> +       }
> +
> +       ret = reset_control_deassert(data->reset);
> +       if (ret) {
> +               dev_err(&pdev->dev, "reset deassert failed: %d\n", ret);
> +               goto err_disable_ths;
> +       }
> +
> +       ret = data->type->init(data);
> +       if (ret)
> +               goto err_reset_assert;
> +
> +       data->tzd = thermal_zone_of_sensor_register(&pdev->dev, 0, data,
> +                                                                       &sunxi_ths_thermal_ops);
> +       if (IS_ERR(data->tzd)) {
> +               ret = PTR_ERR(data->tzd);
> +               dev_err(&pdev->dev, "failed to register thermal zone: %d\n",
> +                               ret);
> +               goto err_reset_assert;
> +       }
> +
> +       platform_set_drvdata(pdev, data);
> +       return 0;
> +
> +err_reset_assert:
> +       reset_control_assert(data->reset);
> +err_disable_ths:
> +       clk_disable_unprepare(data->clk);
> +err_disable_bus:
> +       clk_disable_unprepare(data->busclk);
> +       return ret;
> +}
> +
> +static int sunxi_ths_remove(struct platform_device *pdev)
> +{
> +       struct sunxi_ths_data *data = platform_get_drvdata(pdev);
> +
> +       thermal_zone_of_sensor_unregister(&pdev->dev, data->tzd);
> +       reset_control_assert(data->reset);
> +       clk_disable_unprepare(data->clk);
> +       clk_disable_unprepare(data->busclk);
> +       return 0;
> +}
> +
> +static struct platform_driver sunxi_ths_driver = {
> +       .probe = sunxi_ths_probe,
> +       .remove = sunxi_ths_remove,
> +       .driver = {
> +               .name = "sunxi_ths",
> +               .of_match_table = sunxi_ths_id_table,
> +       },
> +};
> +
> +module_platform_driver(sunxi_ths_driver);
> +
> +MODULE_AUTHOR("Josef Gajdusek <atx at atx.name>");
> +MODULE_DESCRIPTION("Sunxi THS driver");
> +MODULE_LICENSE("GPL v2");
> --
> 2.4.10
>



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