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 = tz->devdata; 50 unsigned int val; 51 int ret; 52 53 ret = regmap_read(mtherm->rmap, MAX77620_REG_STATLBT, &val); 54 if (ret < 0) { 55 dev_err(mtherm->dev, "Failed to read STATLBT: %d\n", ret); 56 return ret; 57 } 58 59 if (val & MAX77620_IRQ_TJALRM2_MASK) 60 *temp = MAX77620_TJALARM2_TEMP; 61 else if (val & MAX77620_IRQ_TJALRM1_MASK) 62 *temp = MAX77620_TJALARM1_TEMP; 63 else 64 *temp = MAX77620_NORMAL_OPERATING_TEMP; 65 66 return 0; 67 } 68 69 static const struct thermal_zone_device_ops max77620_thermal_ops = { 70 .get_temp = max77620_thermal_read_temp, 71 }; 72 73 static irqreturn_t max77620_thermal_irq(int irq, void *data) 74 { 75 struct max77620_therm_info *mtherm = data; 76 77 if (irq == mtherm->irq_tjalarm1) 78 dev_warn(mtherm->dev, "Junction Temp Alarm1(120C) occurred\n"); 79 else if (irq == mtherm->irq_tjalarm2) 80 dev_crit(mtherm->dev, "Junction Temp Alarm2(140C) occurred\n"); 81 82 thermal_zone_device_update(mtherm->tz_device, 83 THERMAL_EVENT_UNSPECIFIED); 84 85 return IRQ_HANDLED; 86 } 87 88 static int max77620_thermal_probe(struct platform_device *pdev) 89 { 90 struct max77620_therm_info *mtherm; 91 int ret; 92 93 mtherm = devm_kzalloc(&pdev->dev, sizeof(*mtherm), GFP_KERNEL); 94 if (!mtherm) 95 return -ENOMEM; 96 97 mtherm->irq_tjalarm1 = platform_get_irq(pdev, 0); 98 mtherm->irq_tjalarm2 = platform_get_irq(pdev, 1); 99 if ((mtherm->irq_tjalarm1 < 0) || (mtherm->irq_tjalarm2 < 0)) { 100 dev_err(&pdev->dev, "Alarm irq number not available\n"); 101 return -EINVAL; 102 } 103 104 mtherm->dev = &pdev->dev; 105 mtherm->rmap = dev_get_regmap(pdev->dev.parent, NULL); 106 if (!mtherm->rmap) { 107 dev_err(&pdev->dev, "Failed to get parent regmap\n"); 108 return -ENODEV; 109 } 110 111 /* 112 * The reference taken to the parent's node which will be balanced on 113 * reprobe or on platform-device release. 114 */ 115 device_set_of_node_from_dev(&pdev->dev, pdev->dev.parent); 116 117 mtherm->tz_device = devm_thermal_of_zone_register(&pdev->dev, 0, 118 mtherm, &max77620_thermal_ops); 119 if (IS_ERR(mtherm->tz_device)) { 120 ret = PTR_ERR(mtherm->tz_device); 121 dev_err(&pdev->dev, "Failed to register thermal zone: %d\n", 122 ret); 123 return ret; 124 } 125 126 ret = devm_request_threaded_irq(&pdev->dev, mtherm->irq_tjalarm1, NULL, 127 max77620_thermal_irq, 128 IRQF_ONESHOT | IRQF_SHARED, 129 dev_name(&pdev->dev), mtherm); 130 if (ret < 0) { 131 dev_err(&pdev->dev, "Failed to request irq1: %d\n", ret); 132 return ret; 133 } 134 135 ret = devm_request_threaded_irq(&pdev->dev, mtherm->irq_tjalarm2, NULL, 136 max77620_thermal_irq, 137 IRQF_ONESHOT | IRQF_SHARED, 138 dev_name(&pdev->dev), mtherm); 139 if (ret < 0) { 140 dev_err(&pdev->dev, "Failed to request irq2: %d\n", ret); 141 return ret; 142 } 143 144 platform_set_drvdata(pdev, mtherm); 145 146 return 0; 147 } 148 149 static struct platform_device_id max77620_thermal_devtype[] = { 150 { .name = "max77620-thermal", }, 151 {}, 152 }; 153 MODULE_DEVICE_TABLE(platform, max77620_thermal_devtype); 154 155 static struct platform_driver max77620_thermal_driver = { 156 .driver = { 157 .name = "max77620-thermal", 158 }, 159 .probe = max77620_thermal_probe, 160 .id_table = max77620_thermal_devtype, 161 }; 162 163 module_platform_driver(max77620_thermal_driver); 164 165 MODULE_DESCRIPTION("Max77620 Junction temperature Thermal driver"); 166 MODULE_AUTHOR("Laxman Dewangan <ldewangan@nvidia.com>"); 167 MODULE_AUTHOR("Mallikarjun Kasoju <mkasoju@nvidia.com>"); 168 MODULE_LICENSE("GPL v2"); 169