Re: [PATCH V4 2/2] thermal: max77620: Add thermal driver for reporting junction temp

[Zhang Rui <rui.zhang@intel.com>]

On 二, 2016-06-07 at 16:22 +0530, Laxman Dewangan wrote:
> Maxim Semiconductor Max77620 supports alarm interrupts when
> its die temperature crosses 120C and 140C. These threshold
> temperatures are not configurable.
> 
> Add thermal driver to register PMIC die temperature as thermal
> zone sensor and capture the die temperature warning interrupts
> to notifying the client.
> 
> Signed-off-by: Laxman Dewangan <ldewangan@nvidia.com>
> 
> ---
> The patch was sent earlier but dependent mfd header file was not
> available on tree and hence it was not applied.
> The mfd patches are in rc-4.7 and hence resending again this patch.
> 
> Changes from V3:
> - Added comment on the function get_temp() that absolute temp can not
> be
>   available.
> 
>  drivers/thermal/Kconfig            |  10 +++
>  drivers/thermal/Makefile           |   1 +
>  drivers/thermal/thermal-max77620.c | 165
> +++++++++++++++++++++++++++++++++++++

Just one comment,
can you please rename it to max77620_thermal.c, just like the others?

thanks,
rui

>  3 files changed, 176 insertions(+)
>  create mode 100644 drivers/thermal/thermal-max77620.c
> 
> diff --git a/drivers/thermal/Kconfig b/drivers/thermal/Kconfig
> index 2d702ca..a2b4433 100644
> --- a/drivers/thermal/Kconfig
> +++ b/drivers/thermal/Kconfig
> @@ -195,6 +195,16 @@ config IMX_THERMAL
>  	  cpufreq is used as the cooling device to throttle CPUs
> when the
>  	  passive trip is crossed.
>  
> +config MAX77620_THERMAL
> +	tristate "Temperature sensor driver for Maxim MAX77620 PMIC"
> +	depends on MFD_MAX77620
> +	depends on OF
> +	help
> +	  Support for die junction temperature warning alarm for
> Maxim
> +	  Semiconductor PMIC MAX77620 device. Device generates two
> alarm
> +	  interrupts when PMIC die temperature cross the threshold
> of
> +	  120 degC and 140 degC.
> +
>  config SPEAR_THERMAL
>  	tristate "SPEAr thermal sensor driver"
>  	depends on PLAT_SPEAR || COMPILE_TEST
> diff --git a/drivers/thermal/Makefile b/drivers/thermal/Makefile
> index 10b07c1..90e1d7e 100644
> --- a/drivers/thermal/Makefile
> +++ b/drivers/thermal/Makefile
> @@ -37,6 +37,7 @@ obj-$(CONFIG_DB8500_THERMAL)	+=
> db8500_thermal.o
>  obj-$(CONFIG_ARMADA_THERMAL)	+= armada_thermal.o
>  obj-$(CONFIG_TANGO_THERMAL)	+= tango_thermal.o
>  obj-$(CONFIG_IMX_THERMAL)	+= imx_thermal.o
> +obj-$(CONFIG_MAX77620_THERMAL)	+= thermal-max77620.o
>  obj-$(CONFIG_DB8500_CPUFREQ_COOLING)	+=
> db8500_cpufreq_cooling.o
>  obj-$(CONFIG_INTEL_POWERCLAMP)	+= intel_powerclamp.o
>  obj-$(CONFIG_X86_PKG_TEMP_THERMAL)	+= x86_pkg_temp_thermal.o
> diff --git a/drivers/thermal/thermal-max77620.c
> b/drivers/thermal/thermal-max77620.c
> new file mode 100644
> index 0000000..32ae1be
> --- /dev/null
> +++ b/drivers/thermal/thermal-max77620.c
> @@ -0,0 +1,165 @@
> +/*
> + * Junction temperature thermal driver for Maxim Max77620.
> + *
> + * Copyright (c) 2016, NVIDIA CORPORATION.  All rights reserved.
> + *
> + * Author: Laxman Dewangan <ldewangan@nvidia.com>
> + *	   Mallikarjun Kasoju <mkasoju@nvidia.com>
> + *
> + * This program is free software; you can redistribute it and/or
> modify it
> + * under the terms and conditions of the GNU General Public License,
> + * version 2, as published by the Free Software Foundation.
> + */
> +
> +#include <linux/irq.h>
> +#include <linux/interrupt.h>
> +#include <linux/mfd/max77620.h>
> +#include <linux/module.h>
> +#include <linux/of.h>
> +#include <linux/platform_device.h>
> +#include <linux/regmap.h>
> +#include <linux/slab.h>
> +#include <linux/thermal.h>
> +
> +#define MAX77620_NORMAL_OPERATING_TEMP	100000
> +#define MAX77620_TJALARM1_TEMP		120000
> +#define MAX77620_TJALARM2_TEMP		140000
> +
> +struct max77620_therm_info {
> +	struct device			*dev;
> +	struct regmap			*rmap;
> +	struct thermal_zone_device	*tz_device;
> +	int				irq_tjalarm1;
> +	int				irq_tjalarm2;
> +};
> +
> +/**
> + * max77620_thermal_read_temp: Read PMIC die temperatue.
> + * @data:	Device specific data.
> + * temp:	Temperature in millidegrees Celsius
> + *
> + * The actual temperature of PMIC die is not available from PMIC.
> + * PMIC only tells the status if it has crossed or not the threshold
> level
> + * of 120degC or 140degC.
> + * If threshold has not been crossed then assume die temperature as
> 100degC
> + * else 120degC or 140deG based on the PMIC die temp threshold
> status.
> + *
> + * Return 0 on success otherwise error number to show reason of
> failure.
> + */
> +
> +static int max77620_thermal_read_temp(void *data, int *temp)
> +{
> +	struct max77620_therm_info *mtherm = data;
> +	unsigned int val;
> +	int ret;
> +
> +	ret = regmap_read(mtherm->rmap, MAX77620_REG_STATLBT, &val);
> +	if (ret < 0) {
> +		dev_err(mtherm->dev, "Failed to read STATLBT: %d\n",
> ret);
> +		return ret;
> +	}
> +
> +	if (val & MAX77620_IRQ_TJALRM2_MASK)
> +		*temp = MAX77620_TJALARM2_TEMP;
> +	else if (val & MAX77620_IRQ_TJALRM1_MASK)
> +		*temp = MAX77620_TJALARM1_TEMP;
> +	else
> +		*temp = MAX77620_NORMAL_OPERATING_TEMP;
> +
> +	return 0;
> +}
> +
> +static const struct thermal_zone_of_device_ops max77620_thermal_ops
> = {
> +	.get_temp = max77620_thermal_read_temp,
> +};
> +
> +static irqreturn_t max77620_thermal_irq(int irq, void *data)
> +{
> +	struct max77620_therm_info *mtherm = data;
> +
> +	if (irq == mtherm->irq_tjalarm1)
> +		dev_warn(mtherm->dev, "Junction Temp Alarm1(120C)
> occurred\n");
> +	else if (irq == mtherm->irq_tjalarm2)
> +		dev_crit(mtherm->dev, "Junction Temp Alarm2(140C)
> occurred\n");
> +
> +	thermal_zone_device_update(mtherm->tz_device);
> +
> +	return IRQ_HANDLED;
> +}
> +
> +static int max77620_thermal_probe(struct platform_device *pdev)
> +{
> +	struct max77620_therm_info *mtherm;
> +	int ret;
> +
> +	pdev->dev.of_node = pdev->dev.parent->of_node;
> +
> +	mtherm = devm_kzalloc(&pdev->dev, sizeof(*mtherm),
> GFP_KERNEL);
> +	if (!mtherm)
> +		return -ENOMEM;
> +
> +	mtherm->irq_tjalarm1 = platform_get_irq(pdev, 0);
> +	mtherm->irq_tjalarm2 = platform_get_irq(pdev, 1);
> +	if ((mtherm->irq_tjalarm1 < 0) || (mtherm->irq_tjalarm2 <
> 0)) {
> +		dev_err(&pdev->dev, "Alarm irq number not
> available\n");
> +		return -EINVAL;
> +	}
> +
> +	mtherm->dev = &pdev->dev;
> +	mtherm->rmap = dev_get_regmap(pdev->dev.parent, NULL);
> +	if (!mtherm->rmap) {
> +		dev_err(&pdev->dev, "Failed to get parent
> regmap\n");
> +		return -ENODEV;
> +	}
> +
> +	mtherm->tz_device =
> devm_thermal_zone_of_sensor_register(&pdev->dev, 0,
> +				mtherm, &max77620_thermal_ops);
> +	if (IS_ERR(mtherm->tz_device)) {
> +		ret = PTR_ERR(mtherm->tz_device);
> +		dev_err(&pdev->dev, "Failed to register thermal
> zone: %d\n",
> +			ret);
> +		return ret;
> +	}
> +
> +	ret = devm_request_threaded_irq(&pdev->dev, mtherm-
> >irq_tjalarm1, NULL,
> +					max77620_thermal_irq,
> +					IRQF_ONESHOT | IRQF_SHARED,
> +					dev_name(&pdev->dev),
> mtherm);
> +	if (ret < 0) {
> +		dev_err(&pdev->dev, "Failed to request irq1: %d\n",
> ret);
> +		return ret;
> +	}
> +
> +	ret = devm_request_threaded_irq(&pdev->dev, mtherm-
> >irq_tjalarm2, NULL,
> +					max77620_thermal_irq,
> +					IRQF_ONESHOT | IRQF_SHARED,
> +					dev_name(&pdev->dev),
> mtherm);
> +	if (ret < 0) {
> +		dev_err(&pdev->dev, "Failed to request irq2: %d\n",
> ret);
> +		return ret;
> +	}
> +
> +	platform_set_drvdata(pdev, mtherm);
> +
> +	return 0;
> +}
> +
> +static struct platform_device_id max77620_thermal_devtype[] = {
> +	{ .name = "max77620-thermal", },
> +	{},
> +};
> +
> +static struct platform_driver max77620_thermal_driver = {
> +	.driver = {
> +		.name = "max77620-thermal",
> +	},
> +	.probe = max77620_thermal_probe,
> +	.id_table = max77620_thermal_devtype,
> +};
> +
> +module_platform_driver(max77620_thermal_driver);
> +
> +MODULE_DESCRIPTION("Max77620 Junction temperature Thermal driver");
> +MODULE_AUTHOR("Laxman Dewangan <ldewangan@nvidia.com>");
> +MODULE_AUTHOR("Mallikarjun Kasoju <mkasoju@nvidia.com>");
> +MODULE_LICENSE("GPL v2");