drivers/thermal/max77620_thermal.c

   1 // SPDX-License-Identifier: GPL-2.0-only
   2 /*
   3  * Junction temperature thermal driver for Maxim Max77620.
   4  *
   5  * Copyright (c) 2016, NVIDIA CORPORATION.  All rights reserved.
   6  *
   7  * Author: Laxman Dewangan <ldewangan@nvidia.com>
   8  *         Mallikarjun Kasoju <mkasoju@nvidia.com>
   9  */
  10
  11 #include <linux/irq.h>
  12 #include <linux/interrupt.h>
  13 #include <linux/mfd/max77620.h>
  14 #include <linux/module.h>
  15 #include <linux/of.h>
  16 #include <linux/platform_device.h>
  17 #include <linux/regmap.h>
  18 #include <linux/slab.h>
  19 #include <linux/thermal.h>
  20
  21 #define MAX77620_NORMAL_OPERATING_TEMP  100000
  22 #define MAX77620_TJALARM1_TEMP          120000
  23 #define MAX77620_TJALARM2_TEMP          140000
  24
  25 struct max77620_therm_info {
  26         struct device                   *dev;
  27         struct regmap                   *rmap;
  28         struct thermal_zone_device      *tz_device;
  29         int                             irq_tjalarm1;
  30         int                             irq_tjalarm2;
  31 };
  32
  33 /**
  34  * max77620_thermal_read_temp: Read PMIC die temperatue.
  35  * @data:       Device specific data.
  36  * @temp:       Temperature in millidegrees Celsius
  37  *
  38  * The actual temperature of PMIC die is not available from PMIC.
  39  * PMIC only tells the status if it has crossed or not the threshold level
  40  * of 120degC or 140degC.
  41  * If threshold has not been crossed then assume die temperature as 100degC
  42  * else 120degC or 140deG based on the PMIC die temp threshold status.
  43  *
  44  * Return 0 on success otherwise error number to show reason of failure.
  45  */
  46
  47 static int max77620_thermal_read_temp(struct thermal_zone_device *tz, int *temp)
  48 {
  49         struct max77620_therm_info *mtherm = thermal_zone_device_priv(tz);
  50         unsigned int val;
  51         int ret;
  52
  53         ret = regmap_read(mtherm->rmap, MAX77620_REG_STATLBT, &val);
  54         if (ret < 0)
  55                 return ret;
  56
  57         if (val & MAX77620_IRQ_TJALRM2_MASK)
  58                 *temp = MAX77620_TJALARM2_TEMP;
  59         else if (val & MAX77620_IRQ_TJALRM1_MASK)
  60                 *temp = MAX77620_TJALARM1_TEMP;
  61         else
  62                 *temp = MAX77620_NORMAL_OPERATING_TEMP;
  63
  64         return 0;
  65 }
  66
  67 static const struct thermal_zone_device_ops max77620_thermal_ops = {
  68         .get_temp = max77620_thermal_read_temp,
  69 };
  70
  71 static irqreturn_t max77620_thermal_irq(int irq, void *data)
  72 {
  73         struct max77620_therm_info *mtherm = data;
  74
  75         if (irq == mtherm->irq_tjalarm1)
  76                 dev_warn(mtherm->dev, "Junction Temp Alarm1(120C) occurred\n");
  77         else if (irq == mtherm->irq_tjalarm2)
  78                 dev_crit(mtherm->dev, "Junction Temp Alarm2(140C) occurred\n");
  79
  80         thermal_zone_device_update(mtherm->tz_device,
  81                                    THERMAL_EVENT_UNSPECIFIED);
  82
  83         return IRQ_HANDLED;
  84 }
  85
  86 static int max77620_thermal_probe(struct platform_device *pdev)
  87 {
  88         struct max77620_therm_info *mtherm;
  89         int ret;
  90
  91         mtherm = devm_kzalloc(&pdev->dev, sizeof(*mtherm), GFP_KERNEL);
  92         if (!mtherm)
  93                 return -ENOMEM;
  94
  95         mtherm->irq_tjalarm1 = platform_get_irq(pdev, 0);
  96         mtherm->irq_tjalarm2 = platform_get_irq(pdev, 1);
  97         if ((mtherm->irq_tjalarm1 < 0) || (mtherm->irq_tjalarm2 < 0)) {
  98                 dev_err(&pdev->dev, "Alarm irq number not available\n");
  99                 return -EINVAL;
 100         }
 101
 102         mtherm->dev = &pdev->dev;
 103         mtherm->rmap = dev_get_regmap(pdev->dev.parent, NULL);
 104         if (!mtherm->rmap) {
 105                 dev_err(&pdev->dev, "Failed to get parent regmap\n");
 106                 return -ENODEV;
 107         }
 108
 109         /*
 110          * The reference taken to the parent's node which will be balanced on
 111          * reprobe or on platform-device release.
 112          */
 113         device_set_of_node_from_dev(&pdev->dev, pdev->dev.parent);
 114
 115         mtherm->tz_device = devm_thermal_of_zone_register(&pdev->dev, 0,
 116                                 mtherm, &max77620_thermal_ops);
 117         if (IS_ERR(mtherm->tz_device))
 118                 return PTR_ERR(mtherm->tz_device);
 119
 120         ret = devm_request_threaded_irq(&pdev->dev, mtherm->irq_tjalarm1, NULL,
 121                                         max77620_thermal_irq,
 122                                         IRQF_ONESHOT | IRQF_SHARED,
 123                                         dev_name(&pdev->dev), mtherm);
 124         if (ret < 0) {
 125                 dev_err(&pdev->dev, "Failed to request irq1: %d\n", ret);
 126                 return ret;
 127         }
 128
 129         ret = devm_request_threaded_irq(&pdev->dev, mtherm->irq_tjalarm2, NULL,
 130                                         max77620_thermal_irq,
 131                                         IRQF_ONESHOT | IRQF_SHARED,
 132                                         dev_name(&pdev->dev), mtherm);
 133         if (ret < 0) {
 134                 dev_err(&pdev->dev, "Failed to request irq2: %d\n", ret);
 135                 return ret;
 136         }
 137
 138         return 0;
 139 }
 140
 141 static struct platform_device_id max77620_thermal_devtype[] = {
 142         { .name = "max77620-thermal", },
 143         {},
 144 };
 145 MODULE_DEVICE_TABLE(platform, max77620_thermal_devtype);
 146
 147 static struct platform_driver max77620_thermal_driver = {
 148         .driver = {
 149                 .name = "max77620-thermal",
 150         },
 151         .probe = max77620_thermal_probe,
 152         .id_table = max77620_thermal_devtype,
 153 };
 154
 155 module_platform_driver(max77620_thermal_driver);
 156
 157 MODULE_DESCRIPTION("Max77620 Junction temperature Thermal driver");
 158 MODULE_AUTHOR("Laxman Dewangan <ldewangan@nvidia.com>");
 159 MODULE_AUTHOR("Mallikarjun Kasoju <mkasoju@nvidia.com>");
 160 MODULE_LICENSE("GPL v2");