linux-imx

/*

 * 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;