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"); 161