Thanks, I've incorporated all the suggestions (and more :)), except for the threaded IRQ, which si expalined below.
regards,
Ondrej
On 24.6.2016 05:09, Chen-Yu Tsai wrote:
> Hi,
>
> On Fri, Jun 24, 2016 at 3:20 AM, <meg...@megous.com> wrote:
>> From: Ondrej Jirman <meg...@megous.com>
>>
>
> The subject could read:
>
> thermal: sun8i_ths: Add support for the thermal sensor on Allwinner H3
>
>> This patch adds support for the sun8i thermal sensor on
>> Allwinner H3 SoC.
>>
>> Signed-off-by: Ondřej Jirman <meg...@megous.com>
>> ---
>> drivers/thermal/Kconfig | 7 ++
>> drivers/thermal/Makefile | 1 +
>> drivers/thermal/sun8i_ths.c | 295
>> ++++++++++++++++++++++++++++++++++++++++++++
>> 3 files changed, 303 insertions(+)
>> create mode 100644 drivers/thermal/sun8i_ths.c
>>
>> diff --git a/drivers/thermal/Kconfig b/drivers/thermal/Kconfig
>> index 2d702ca..3de0f8d 100644
>> --- a/drivers/thermal/Kconfig
>> +++ b/drivers/thermal/Kconfig
>> @@ -351,6 +351,13 @@ config MTK_THERMAL
>> Enable this option if you want to have support for thermal
>> management
>> controller present in Mediatek SoCs
>>
>> +config SUN8I_THS
>> + tristate "sun8i THS driver"
>
> Explain THS.
>
>> + depends on MACH_SUN8I
>> + depends on OF
>> + help
>> + Enable this to support thermal reporting on some newer Allwinner
>> SoCs.
>> +
>> menu "Texas Instruments thermal drivers"
>> depends on ARCH_HAS_BANDGAP || COMPILE_TEST
>> depends on HAS_IOMEM
>> diff --git a/drivers/thermal/Makefile b/drivers/thermal/Makefile
>> index 10b07c1..7261ee8 100644
>> --- a/drivers/thermal/Makefile
>> +++ b/drivers/thermal/Makefile
>> @@ -51,3 +51,4 @@ obj-$(CONFIG_TEGRA_SOCTHERM) += tegra/
>> obj-$(CONFIG_HISI_THERMAL) += hisi_thermal.o
>> obj-$(CONFIG_MTK_THERMAL) += mtk_thermal.o
>> obj-$(CONFIG_GENERIC_ADC_THERMAL) += thermal-generic-adc.o
>> +obj-$(CONFIG_SUN8I_THS) += sun8i_ths.o
>> diff --git a/drivers/thermal/sun8i_ths.c b/drivers/thermal/sun8i_ths.c
>> new file mode 100644
>> index 0000000..618ccc3
>> --- /dev/null
>> +++ b/drivers/thermal/sun8i_ths.c
>> @@ -0,0 +1,295 @@
>> +/*
>> + * sun8i THS driver
>
> Explain THS.
>
>> + *
>> + * Copyright (C) 2016 Ondřej Jirman
>> + * Based on the work of Josef Gajdusek <a...@atx.name>
>> + *
>> + * 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.h>
>> +#include <linux/interrupt.h>
>> +#include <linux/io.h>
>> +#include <linux/module.h>
>> +#include <linux/nvmem-consumer.h>
>> +#include <linux/of_device.h>
>> +#include <linux/platform_device.h>
>> +#include <linux/reset.h>
>> +#include <linux/slab.h>
>> +#include <linux/thermal.h>
>> +#include <linux/printk.h>
>> +
>> +#define THS_H3_CTRL0 0x00
>> +#define THS_H3_CTRL2 0x40
>> +#define THS_H3_INT_CTRL 0x44
>> +#define THS_H3_STAT 0x48
>> +#define THS_H3_FILTER 0x70
>> +#define THS_H3_CDATA 0x74
>> +#define THS_H3_DATA 0x80
>> +
>> +#define THS_H3_CTRL0_SENSOR_ACQ0_OFFS 0
>> +#define THS_H3_CTRL0_SENSOR_ACQ0(x) \
>> + ((x) << THS_H3_CTRL0_SENSOR_ACQ0_OFFS)
>> +#define THS_H3_CTRL2_SENSE_EN_OFFS 0
>> +#define THS_H3_CTRL2_SENSE_EN \
>> + BIT(THS_H3_CTRL2_SENSE_EN_OFFS)
>> +#define THS_H3_CTRL2_SENSOR_ACQ1_OFFS 16
>> +#define THS_H3_CTRL2_SENSOR_ACQ1(x) \
>> + ((x) << THS_H3_CTRL2_SENSOR_ACQ1_OFFS)
>> +
>> +#define THS_H3_INT_CTRL_DATA_IRQ_EN_OFFS 8
>> +#define THS_H3_INT_CTRL_DATA_IRQ_EN \
>> + BIT(THS_H3_INT_CTRL_DATA_IRQ_EN_OFFS)
>> +#define THS_H3_INT_CTRL_THERMAL_PER_OFFS 12
>> +#define THS_H3_INT_CTRL_THERMAL_PER(x) \
>> + ((x) << THS_H3_INT_CTRL_THERMAL_PER_OFFS)
>> +
>> +#define THS_H3_STAT_DATA_IRQ_STS_OFFS 8
>> +#define THS_H3_STAT_DATA_IRQ_STS \
>> + BIT(THS_H3_STAT_DATA_IRQ_STS_OFFS)
>> +
>> +#define THS_H3_FILTER_TYPE_OFFS 0
>> +#define THS_H3_FILTER_TYPE(x) \
>> + ((x) << THS_H3_FILTER_TYPE_OFFS)
>> +#define THS_H3_FILTER_EN_OFFS 2
>> +#define THS_H3_FILTER_EN \
>> + BIT(THS_H3_FILTER_EN_OFFS)
>
> Is it really necessary to split the lines of all the macros?
> It makes it harder to find and read stuff.
>
> You're also not using any of the *_OFFS macros in the actual code,
> so just drop them.
>
>> +
>> +#define THS_H3_CLK_IN 40000000 /* Hz */
>> +#define THS_H3_DATA_PERIOD 330 /* ms */
>> +
>> +#define THS_H3_FILTER_TYPE_VALUE 2 /* average over 2^(n+1)
>> samples */
>> +#define THS_H3_FILTER_DIV (1 <<
>> (THS_H3_FILTER_TYPE_VALUE + 1))
>> +#define THS_H3_INT_CTRL_THERMAL_PER_VALUE \
>> + (THS_H3_DATA_PERIOD * (THS_H3_CLK_IN / 1000) / THS_H3_FILTER_DIV /
>> 4096 - 1)
>> +#define THS_H3_CTRL0_SENSOR_ACQ0_VALUE 0x3f /* 16us */
>> +#define THS_H3_CTRL2_SENSOR_ACQ1_VALUE 0x3f
>> +
>> +struct sun8i_ths_data {
>> + struct reset_control *reset;
>> + struct clk *clk;
>> + struct clk *busclk;
>> + void __iomem *regs;
>> + struct nvmem_cell *calcell;
>> + struct platform_device *pdev;
>> + struct thermal_zone_device *tzd;
>> + u32 temp;
>> +};
>> +
>> +static int sun8i_ths_get_temp(void *_data, int *out)
>> +{
>> + struct sun8i_ths_data *data = _data;
>> +
>> + if (data->temp == 0)
>> + return -EINVAL;
>> +
>> + /* Formula and parameters from the Allwinner 3.4 kernel */
>> + *out = 217000 - (data->temp * 1000000) / 8253;
>> + return 0;
>> +}
>> +
>> +static irqreturn_t sun8i_ths_irq_thread(int irq, void *_data)
>> +{
>> + struct sun8i_ths_data *data = _data;
>> +
>> + writel(THS_H3_STAT_DATA_IRQ_STS, data->regs + THS_H3_STAT);
>> +
>> + data->temp = readl(data->regs + THS_H3_DATA);
>> + if (data->temp)
>> + thermal_zone_device_update(data->tzd);
>> +
>> + return IRQ_HANDLED;
>> +}
>> +
>> +static int sun8i_ths_h3_init(struct platform_device *pdev,
>> + struct sun8i_ths_data *data)
>> +{
>> + int ret;
>> + size_t callen;
>> + s32 *caldata;
>> +
>> + 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(&pdev->dev, "ahb");
>
> IIRC with the new shared reset control stuff merged, you are supposed
> to specify whether you want a shared or exclusive one when you ask for
> it.
>
> Also you seem to be requesting some resources here, while others
> directly in the probe function. Could you put them in the same place?
> Maybe requesting all resources in the probe function, and this init
> function turns everything on?
>
>> + if (IS_ERR(data->reset)) {
>> + ret = PTR_ERR(data->reset);
>> + dev_err(&pdev->dev, "failed to get reset: %d\n", ret);
>> + return ret;
>> + }
>> +
>> + if (data->calcell) {
>> + caldata = nvmem_cell_read(data->calcell, &callen);
>> + if (IS_ERR(caldata))
>> + return PTR_ERR(caldata);
>
> Check the returned length in case of a bogus cell?
>
>> +
>> + writel(be32_to_cpu(*caldata), data->regs + THS_H3_CDATA);
>> + kfree(caldata);
>> + }
>> +
>> + 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 = clk_set_rate(data->clk, THS_H3_CLK_IN);
>> + if (ret)
>> + goto err_disable_ths;
>> +
>> + writel(THS_H3_CTRL0_SENSOR_ACQ0(THS_H3_CTRL0_SENSOR_ACQ0_VALUE),
>> + data->regs + THS_H3_CTRL0);
>> +
>> writel(THS_H3_INT_CTRL_THERMAL_PER(THS_H3_INT_CTRL_THERMAL_PER_VALUE) |
>> + THS_H3_INT_CTRL_DATA_IRQ_EN,
>> + data->regs + THS_H3_INT_CTRL);
>
> This enables the interrupts. You already requested IRQs from the kernel, which
> means as soon as this line executes, interrupts will start firing.
>
> You should do this last, after you've finishing all the configuration,
> i.e. move this after the next writel calls.
>
>> + writel(THS_H3_FILTER_EN |
>> THS_H3_FILTER_TYPE(THS_H3_FILTER_TYPE_VALUE),
>> + data->regs + THS_H3_FILTER);
>> + writel(THS_H3_CTRL2_SENSOR_ACQ1(THS_H3_CTRL2_SENSOR_ACQ1_VALUE) |
>> + THS_H3_CTRL2_SENSE_EN,
>> + data->regs + THS_H3_CTRL2);
>> +
>> + return 0;
>> +
>> +err_disable_ths:
>> + clk_disable_unprepare(data->clk);
>> +err_disable_bus:
>> + clk_disable_unprepare(data->busclk);
>> +
>> + return ret;
>> +}
>> +
>> +static void sun8i_ths_h3_deinit(struct sun8i_ths_data *data)
>> +{
>> + reset_control_assert(data->reset);
>> + clk_disable_unprepare(data->clk);
>> + clk_disable_unprepare(data->busclk);
>> +}
>> +
>> +static const struct thermal_zone_of_device_ops sun8i_ths_thermal_ops = {
>> + .get_temp = sun8i_ths_get_temp,
>> +};
>> +
>> +static const struct of_device_id sun8i_ths_id_table[] = {
>> + {
>> + .compatible = "allwinner,sun8i-h3-ths",
>> + },
>
> Nit. You could fit it in one line.
>
>> + { /* sentinel */ },
>> +};
>> +MODULE_DEVICE_TABLE(of, sun8i_ths_id_table);
>> +
>> +static int sun8i_ths_probe(struct platform_device *pdev)
>> +{
>> + struct sun8i_ths_data *data;
>> + struct resource *res;
>> + int ret;
>> + int irq;
>> +
>> + data = devm_kzalloc(&pdev->dev, sizeof(*data), GFP_KERNEL);
>> + if (!data)
>> + return -ENOMEM;
>> +
>> + data->pdev = pdev;
>> +
>> + data->calcell = devm_nvmem_cell_get(&pdev->dev, "calibration");
>> + if (IS_ERR(data->calcell)) {
>> + if (PTR_ERR(data->calcell) == -EPROBE_DEFER)
>> + return PTR_ERR(data->calcell);
>> +
>> + data->calcell = NULL; /* No calibration data */
>> + }
>> +
>> + 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;
>> + }
>> +
>> + irq = platform_get_irq(pdev, 0);
>> + if (irq < 0) {
>> + dev_err(&pdev->dev, "failed to get IRQ: %d\n", irq);
>> + return irq;
>> + }
>> +
>> + ret = devm_request_threaded_irq(&pdev->dev, irq, NULL,
>> + sun8i_ths_irq_thread, IRQF_ONESHOT,
>> + dev_name(&pdev->dev), data);
>
> Is a threaded irq required? The thermal core seems to use atomics,
> so this shouldn't be necessary.
As I understand it, thermal_zone_device_update(data->tzd) can do quite a
lot of work and all other thermal drivers defer this call from the hard
irq handler. So, yes, it is necessary.
>> + if (ret)
>> + return ret;
>> +
>> + ret = sun8i_ths_h3_init(pdev, data);
>> + if (ret)
>> + return ret;
>> +
>> + data->tzd = thermal_zone_of_sensor_register(&pdev->dev, 0, data,
>> + &sun8i_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_deinit;
>> + }
>> +
>> + platform_set_drvdata(pdev, data);
>> + return 0;
>> +
>> +err_deinit:
>> + sun8i_ths_h3_deinit(data);
>> + return ret;
>> +}
>> +
>> +static int sun8i_ths_remove(struct platform_device *pdev)
>> +{
>> + struct sun8i_ths_data *data = platform_get_drvdata(pdev);
>> +
>> + thermal_zone_of_sensor_unregister(&pdev->dev, data->tzd);
>> + sun8i_ths_h3_deinit(data);
>> + return 0;
>> +}
>> +
>> +static struct platform_driver sun8i_ths_driver = {
>> + .probe = sun8i_ths_probe,
>> + .remove = sun8i_ths_remove,
>> + .driver = {
>> + .name = "sun8i_ths",
>> + .of_match_table = sun8i_ths_id_table,
>> + },
>> +};
>> +
>> +module_platform_driver(sun8i_ths_driver);
>> +
>> +MODULE_AUTHOR("Ondřej Jirman <meg...@megous.com>");
>> +MODULE_DESCRIPTION("sun8i THS driver");
>
> Explain THS.
>
> Regards
> ChenYu
>
>> +MODULE_LICENSE("GPL v2");
>> --
>> 2.9.0
>>
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