On Sat, Jun 25, 2016 at 05:44:59AM +0200, [email protected] wrote: > From: Ondrej Jirman <[email protected]> > > This patch adds support for the sun8i thermal sensor on > Allwinner H3 SoC. > > Signed-off-by: Ondřej Jirman <[email protected]> > --- > v2: > - removed incorrect use of SID driver in sun8i_ths > - read calibration data directly from iomem > - better explanation for the thermal sensor driver > - dt documentation fixes > - dropped unncecessary macros and init code reorganization > - moved resource aquisition from init to probe function > - deassert reset after clock rate is set, not before > - enable irq after all other registers are configured > --- > drivers/thermal/Kconfig | 7 ++ > drivers/thermal/Makefile | 1 + > drivers/thermal/sun8i_ths.c | 260 > ++++++++++++++++++++++++++++++++++++++++++++ > 3 files changed, 268 insertions(+) > create mode 100644 drivers/thermal/sun8i_ths.c > > diff --git a/drivers/thermal/Kconfig b/drivers/thermal/Kconfig > index 2d702ca..d3209d9 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 "Thermal sensor driver for Allwinner H3" > + 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..9ba0f96 > --- /dev/null > +++ b/drivers/thermal/sun8i_ths.c > @@ -0,0 +1,260 @@ > +/* > + * Thermal sensor driver for Allwinner H3 SoC > + * > + * Copyright (C) 2016 Ondřej Jirman > + * Based on the work of Josef Gajdusek <[email protected]> > + * > + * 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/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(x) (x) > +#define THS_H3_CTRL2_SENSE_EN BIT(0) > +#define THS_H3_CTRL2_SENSOR_ACQ1(x) ((x) << 16) > +#define THS_H3_INT_CTRL_DATA_IRQ_EN BIT(8) > +#define THS_H3_INT_CTRL_THERMAL_PER(x) ((x) << 12) > +#define THS_H3_STAT_DATA_IRQ_STS BIT(8) > +#define THS_H3_FILTER_TYPE(x) ((x) << 0) > +#define THS_H3_FILTER_EN BIT(2) > + > +#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; > + void __iomem *calreg; > + 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 - (int)((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 void sun8i_ths_h3_init(struct sun8i_ths_data *data) > +{ > + u32 caldata; > + > + caldata = readl(data->calreg) & 0xfff; > + if (caldata != 0) > + writel(caldata, data->regs + THS_H3_CDATA); > + > + writel(THS_H3_CTRL0_SENSOR_ACQ0(THS_H3_CTRL0_SENSOR_ACQ0_VALUE), > + data->regs + THS_H3_CTRL0); > + 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); > + 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); > +} > + > +static const struct thermal_zone_of_device_ops sun8i_ths_thermal_ops = { > + .get_temp = sun8i_ths_get_temp, > +}; > + > +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; > + > + res = platform_get_resource(pdev, IORESOURCE_MEM, 0); > + if (!res) { > + dev_err(&pdev->dev, "no memory resources defined\n"); > + return -EINVAL; > + } > + > + 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); > + if (!res) { > + dev_err(&pdev->dev, "no calibration data memory resource > defined\n"); > + return -EINVAL; > + } > + > + data->calreg = devm_ioremap_resource(&pdev->dev, res); > + if (IS_ERR(data->calreg)) { > + ret = PTR_ERR(data->calreg); > + dev_err(&pdev->dev, "failed to ioremap THS registers: %d\n", > ret); > + return ret; > + }
Why did you remove the SID use through the nvmem framework ?!
> +
> + 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);
> + if (ret)
> + return ret;
> +
> + 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");
> + 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 = clk_set_rate(data->clk, THS_H3_CLK_IN);
> + if (ret)
> + goto err_disable_ths;
> +
> + ret = reset_control_deassert(data->reset);
> + if (ret) {
> + dev_err(&pdev->dev, "reset deassert failed: %d\n", ret);
> + goto err_disable_ths;
> + }
Having runtime_pm support would be great.
> + sun8i_ths_h3_init(data);
> +
> + 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_assert_reset;
> + }
You reference data->tzd in your interrupt handler, and the interrupts
have been activated before initializing that field. That is likely to
cause a kernel crash when you receive an interrupt between your
request_irq and that call.
> +
> + platform_set_drvdata(pdev, data);
> + return 0;
> +
> +err_assert_reset:
> + 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 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);
> + reset_control_assert(data->reset);
> + clk_disable_unprepare(data->clk);
> + clk_disable_unprepare(data->busclk);
> + return 0;
> +}
> +
> +static const struct of_device_id sun8i_ths_id_table[] = {
> + { .compatible = "allwinner,sun8i-h3-ths", },
> + { /* sentinel */ },
> +};
> +MODULE_DEVICE_TABLE(of, sun8i_ths_id_table);
> +
> +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 <[email protected]>");
> +MODULE_DESCRIPTION("Thermal sensor driver for Allwinner H3 SoC");
> +MODULE_LICENSE("GPL v2");
Looks quite good otherwise. It looks very similar to the older
touchscreen driver (without the touchscreen part).
Have you tried to merge the two?
Thanks,
Maxime
--
Maxime Ripard, Free Electrons
Embedded Linux, Kernel and Android engineering
http://free-electrons.com
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