1 /* 2 * Junction temperature thermal driver for Maxim Max77620. 3 * 4 * Copyright (c) 2016, NVIDIA CORPORATION. All rights reserved. 5 * 6 * Author: Laxman Dewangan <ldewangan@nvidia.com> 7 * Mallikarjun Kasoju <mkasoju@nvidia.com> 8 * 9 * This program is free software; you can redistribute it and/or modify it 10 * under the terms and conditions of the GNU General Public License, 11 * version 2, as published by the Free Software Foundation. 12 */ 13 14 #include <linux/irq.h> 15 #include <linux/interrupt.h> 16 #include <linux/mfd/max77620.h> 17 #include <linux/module.h> 18 #include <linux/of.h> 19 #include <linux/platform_device.h> 20 #include <linux/regmap.h> 21 #include <linux/slab.h> 22 #include <linux/thermal.h> 23 24 #define MAX77620_NORMAL_OPERATING_TEMP 100000 25 #define MAX77620_TJALARM1_TEMP 120000 26 #define MAX77620_TJALARM2_TEMP 140000 27 28 struct max77620_therm_info { 29 struct device *dev; 30 struct regmap *rmap; 31 struct thermal_zone_device *tz_device; 32 int irq_tjalarm1; 33 int irq_tjalarm2; 34 }; 35 36 /** 37 * max77620_thermal_read_temp: Read PMIC die temperatue. 38 * @data: Device specific data. 39 * temp: Temperature in millidegrees Celsius 40 * 41 * The actual temperature of PMIC die is not available from PMIC. 42 * PMIC only tells the status if it has crossed or not the threshold level 43 * of 120degC or 140degC. 44 * If threshold has not been crossed then assume die temperature as 100degC 45 * else 120degC or 140deG based on the PMIC die temp threshold status. 46 * 47 * Return 0 on success otherwise error number to show reason of failure. 48 */ 49 50 static int max77620_thermal_read_temp(void *data, int *temp) 51 { 52 struct max77620_therm_info *mtherm = data; 53 unsigned int val; 54 int ret; 55 56 ret = regmap_read(mtherm->rmap, MAX77620_REG_STATLBT, &val); 57 if (ret < 0) { 58 dev_err(mtherm->dev, "Failed to read STATLBT: %d\n", ret); 59 return ret; 60 } 61 62 if (val & MAX77620_IRQ_TJALRM2_MASK) 63 *temp = MAX77620_TJALARM2_TEMP; 64 else if (val & MAX77620_IRQ_TJALRM1_MASK) 65 *temp = MAX77620_TJALARM1_TEMP; 66 else 67 *temp = MAX77620_NORMAL_OPERATING_TEMP; 68 69 return 0; 70 } 71 72 static const struct thermal_zone_of_device_ops max77620_thermal_ops = { 73 .get_temp = max77620_thermal_read_temp, 74 }; 75 76 static irqreturn_t max77620_thermal_irq(int irq, void *data) 77 { 78 struct max77620_therm_info *mtherm = data; 79 80 if (irq == mtherm->irq_tjalarm1) 81 dev_warn(mtherm->dev, "Junction Temp Alarm1(120C) occurred\n"); 82 else if (irq == mtherm->irq_tjalarm2) 83 dev_crit(mtherm->dev, "Junction Temp Alarm2(140C) occurred\n"); 84 85 thermal_zone_device_update(mtherm->tz_device, 86 THERMAL_EVENT_UNSPECIFIED); 87 88 return IRQ_HANDLED; 89 } 90 91 static int max77620_thermal_probe(struct platform_device *pdev) 92 { 93 struct max77620_therm_info *mtherm; 94 int ret; 95 96 mtherm = devm_kzalloc(&pdev->dev, sizeof(*mtherm), GFP_KERNEL); 97 if (!mtherm) 98 return -ENOMEM; 99 100 mtherm->irq_tjalarm1 = platform_get_irq(pdev, 0); 101 mtherm->irq_tjalarm2 = platform_get_irq(pdev, 1); 102 if ((mtherm->irq_tjalarm1 < 0) || (mtherm->irq_tjalarm2 < 0)) { 103 dev_err(&pdev->dev, "Alarm irq number not available\n"); 104 return -EINVAL; 105 } 106 107 pdev->dev.of_node = pdev->dev.parent->of_node; 108 109 mtherm->dev = &pdev->dev; 110 mtherm->rmap = dev_get_regmap(pdev->dev.parent, NULL); 111 if (!mtherm->rmap) { 112 dev_err(&pdev->dev, "Failed to get parent regmap\n"); 113 return -ENODEV; 114 } 115 116 mtherm->tz_device = devm_thermal_zone_of_sensor_register(&pdev->dev, 0, 117 mtherm, &max77620_thermal_ops); 118 if (IS_ERR(mtherm->tz_device)) { 119 ret = PTR_ERR(mtherm->tz_device); 120 dev_err(&pdev->dev, "Failed to register thermal zone: %d\n", 121 ret); 122 return ret; 123 } 124 125 ret = devm_request_threaded_irq(&pdev->dev, mtherm->irq_tjalarm1, NULL, 126 max77620_thermal_irq, 127 IRQF_ONESHOT | IRQF_SHARED, 128 dev_name(&pdev->dev), mtherm); 129 if (ret < 0) { 130 dev_err(&pdev->dev, "Failed to request irq1: %d\n", ret); 131 return ret; 132 } 133 134 ret = devm_request_threaded_irq(&pdev->dev, mtherm->irq_tjalarm2, NULL, 135 max77620_thermal_irq, 136 IRQF_ONESHOT | IRQF_SHARED, 137 dev_name(&pdev->dev), mtherm); 138 if (ret < 0) { 139 dev_err(&pdev->dev, "Failed to request irq2: %d\n", ret); 140 return ret; 141 } 142 143 platform_set_drvdata(pdev, mtherm); 144 145 return 0; 146 } 147 148 static struct platform_device_id max77620_thermal_devtype[] = { 149 { .name = "max77620-thermal", }, 150 {}, 151 }; 152 153 static struct platform_driver max77620_thermal_driver = { 154 .driver = { 155 .name = "max77620-thermal", 156 }, 157 .probe = max77620_thermal_probe, 158 .id_table = max77620_thermal_devtype, 159 }; 160 161 module_platform_driver(max77620_thermal_driver); 162 163 MODULE_DESCRIPTION("Max77620 Junction temperature Thermal driver"); 164 MODULE_AUTHOR("Laxman Dewangan <ldewangan@nvidia.com>"); 165 MODULE_AUTHOR("Mallikarjun Kasoju <mkasoju@nvidia.com>"); 166 MODULE_LICENSE("GPL v2"); 167