drivers/thermal/max77620_thermal.c

0001 // SPDX-License-Identifier: GPL-2.0-only
0002 /*
0003  * Junction temperature thermal driver for Maxim Max77620.
0004  *
0005  * Copyright (c) 2016, NVIDIA CORPORATION.  All rights reserved.
0006  *
0007  * Author: Laxman Dewangan <ldewangan@nvidia.com>
0008  *     Mallikarjun Kasoju <mkasoju@nvidia.com>
0009  */
0010
0011 #include <linux/irq.h>
0012 #include <linux/interrupt.h>
0013 #include <linux/mfd/max77620.h>
0014 #include <linux/module.h>
0015 #include <linux/of.h>
0016 #include <linux/platform_device.h>
0017 #include <linux/regmap.h>
0018 #include <linux/slab.h>
0019 #include <linux/thermal.h>
0020
0021 #define MAX77620_NORMAL_OPERATING_TEMP  100000
0022 #define MAX77620_TJALARM1_TEMP      120000
0023 #define MAX77620_TJALARM2_TEMP      140000
0024
0025 struct max77620_therm_info {
0026     struct device           *dev;
0027     struct regmap           *rmap;
0028     struct thermal_zone_device  *tz_device;
0029     int             irq_tjalarm1;
0030     int             irq_tjalarm2;
0031 };
0032
0033 /**
0034  * max77620_thermal_read_temp: Read PMIC die temperatue.
0035  * @data:   Device specific data.
0036  * @temp:   Temperature in millidegrees Celsius
0037  *
0038  * The actual temperature of PMIC die is not available from PMIC.
0039  * PMIC only tells the status if it has crossed or not the threshold level
0040  * of 120degC or 140degC.
0041  * If threshold has not been crossed then assume die temperature as 100degC
0042  * else 120degC or 140deG based on the PMIC die temp threshold status.
0043  *
0044  * Return 0 on success otherwise error number to show reason of failure.
0045  */
0046
0047 static int max77620_thermal_read_temp(void *data, int *temp)
0048 {
0049     struct max77620_therm_info *mtherm = data;
0050     unsigned int val;
0051     int ret;
0052
0053     ret = regmap_read(mtherm->rmap, MAX77620_REG_STATLBT, &val);
0054     if (ret < 0) {
0055         dev_err(mtherm->dev, "Failed to read STATLBT: %d\n", ret);
0056         return ret;
0057     }
0058
0059     if (val & MAX77620_IRQ_TJALRM2_MASK)
0060         *temp = MAX77620_TJALARM2_TEMP;
0061     else if (val & MAX77620_IRQ_TJALRM1_MASK)
0062         *temp = MAX77620_TJALARM1_TEMP;
0063     else
0064         *temp = MAX77620_NORMAL_OPERATING_TEMP;
0065
0066     return 0;
0067 }
0068
0069 static const struct thermal_zone_of_device_ops max77620_thermal_ops = {
0070     .get_temp = max77620_thermal_read_temp,
0071 };
0072
0073 static irqreturn_t max77620_thermal_irq(int irq, void *data)
0074 {
0075     struct max77620_therm_info *mtherm = data;
0076
0077     if (irq == mtherm->irq_tjalarm1)
0078         dev_warn(mtherm->dev, "Junction Temp Alarm1(120C) occurred\n");
0079     else if (irq == mtherm->irq_tjalarm2)
0080         dev_crit(mtherm->dev, "Junction Temp Alarm2(140C) occurred\n");
0081
0082     thermal_zone_device_update(mtherm->tz_device,
0083                    THERMAL_EVENT_UNSPECIFIED);
0084
0085     return IRQ_HANDLED;
0086 }
0087
0088 static int max77620_thermal_probe(struct platform_device *pdev)
0089 {
0090     struct max77620_therm_info *mtherm;
0091     int ret;
0092
0093     mtherm = devm_kzalloc(&pdev->dev, sizeof(*mtherm), GFP_KERNEL);
0094     if (!mtherm)
0095         return -ENOMEM;
0096
0097     mtherm->irq_tjalarm1 = platform_get_irq(pdev, 0);
0098     mtherm->irq_tjalarm2 = platform_get_irq(pdev, 1);
0099     if ((mtherm->irq_tjalarm1 < 0) || (mtherm->irq_tjalarm2 < 0)) {
0100         dev_err(&pdev->dev, "Alarm irq number not available\n");
0101         return -EINVAL;
0102     }
0103
0104     mtherm->dev = &pdev->dev;
0105     mtherm->rmap = dev_get_regmap(pdev->dev.parent, NULL);
0106     if (!mtherm->rmap) {
0107         dev_err(&pdev->dev, "Failed to get parent regmap\n");
0108         return -ENODEV;
0109     }
0110
0111     /*
0112      * The reference taken to the parent's node which will be balanced on
0113      * reprobe or on platform-device release.
0114      */
0115     device_set_of_node_from_dev(&pdev->dev, pdev->dev.parent);
0116
0117     mtherm->tz_device = devm_thermal_zone_of_sensor_register(&pdev->dev, 0,
0118                 mtherm, &max77620_thermal_ops);
0119     if (IS_ERR(mtherm->tz_device)) {
0120         ret = PTR_ERR(mtherm->tz_device);
0121         dev_err(&pdev->dev, "Failed to register thermal zone: %d\n",
0122             ret);
0123         return ret;
0124     }
0125
0126     ret = devm_request_threaded_irq(&pdev->dev, mtherm->irq_tjalarm1, NULL,
0127                     max77620_thermal_irq,
0128                     IRQF_ONESHOT | IRQF_SHARED,
0129                     dev_name(&pdev->dev), mtherm);
0130     if (ret < 0) {
0131         dev_err(&pdev->dev, "Failed to request irq1: %d\n", ret);
0132         return ret;
0133     }
0134
0135     ret = devm_request_threaded_irq(&pdev->dev, mtherm->irq_tjalarm2, NULL,
0136                     max77620_thermal_irq,
0137                     IRQF_ONESHOT | IRQF_SHARED,
0138                     dev_name(&pdev->dev), mtherm);
0139     if (ret < 0) {
0140         dev_err(&pdev->dev, "Failed to request irq2: %d\n", ret);
0141         return ret;
0142     }
0143
0144     platform_set_drvdata(pdev, mtherm);
0145
0146     return 0;
0147 }
0148
0149 static struct platform_device_id max77620_thermal_devtype[] = {
0150     { .name = "max77620-thermal", },
0151     {},
0152 };
0153 MODULE_DEVICE_TABLE(platform, max77620_thermal_devtype);
0154
0155 static struct platform_driver max77620_thermal_driver = {
0156     .driver = {
0157         .name = "max77620-thermal",
0158     },
0159     .probe = max77620_thermal_probe,
0160     .id_table = max77620_thermal_devtype,
0161 };
0162
0163 module_platform_driver(max77620_thermal_driver);
0164
0165 MODULE_DESCRIPTION("Max77620 Junction temperature Thermal driver");
0166 MODULE_AUTHOR("Laxman Dewangan <ldewangan@nvidia.com>");
0167 MODULE_AUTHOR("Mallikarjun Kasoju <mkasoju@nvidia.com>");
0168 MODULE_LICENSE("GPL v2");