linux/drivers/thermal/max77620_thermal.c
Johan Hovold ce046e5d9b thermal: max77620: fix pinmux conflict on reprobe
Use the new helper for reusing a device-tree node of another device
instead of managing the node references explicitly.

This also makes sure that the new of_node_reuse flag is set if the
device is ever reprobed, something which specifically now avoids driver
core from attempting to claim any pinmux resources already claimed by
the parent device.

Fixes: ec4664b3fd ("thermal: max77620: Add thermal driver for reporting junction temp")
Cc: Laxman Dewangan <ldewangan@nvidia.com>
Signed-off-by: Johan Hovold <johan@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-06-13 11:07:32 +02:00

172 lines
4.7 KiB
C

/*
* 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,
THERMAL_EVENT_UNSPECIFIED);
return IRQ_HANDLED;
}
static int max77620_thermal_probe(struct platform_device *pdev)
{
struct max77620_therm_info *mtherm;
int ret;
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;
}
/*
* The reference taken to the parent's node which will be balanced on
* reprobe or on platform-device release.
*/
device_set_of_node_from_dev(&pdev->dev, pdev->dev.parent);
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", },
{},
};
MODULE_DEVICE_TABLE(platform, max77620_thermal_devtype);
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");