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1// SPDX-License-Identifier: GPL-2.0-or-later2/*3 * Thermal device driver for DA9062 and DA90614 * Copyright (C) 2017 Dialog Semiconductor5 */6 7/* When over-temperature is reached, an interrupt from the device will be8 * triggered. Following this event the interrupt will be disabled and9 * periodic transmission of uevents (HOT trip point) should define the10 * first level of temperature supervision. It is expected that any final11 * implementation of the thermal driver will include a .notify() function12 * to implement these uevents to userspace.13 *14 * These uevents are intended to indicate non-invasive temperature control15 * of the system, where the necessary measures for cooling are the16 * responsibility of the host software. Once the temperature falls again,17 * the IRQ is re-enabled so the start of a new over-temperature event can18 * be detected without constant software monitoring.19 */20 21#include <linux/errno.h>22#include <linux/interrupt.h>23#include <linux/module.h>24#include <linux/of.h>25#include <linux/platform_device.h>26#include <linux/regmap.h>27#include <linux/thermal.h>28#include <linux/workqueue.h>29 30#include <linux/mfd/da9062/core.h>31#include <linux/mfd/da9062/registers.h>32 33/* Minimum, maximum and default polling millisecond periods are provided34 * here as an example. It is expected that any final implementation to also35 * include a modification of these settings to match the required36 * application.37 */38#define DA9062_DEFAULT_POLLING_MS_PERIOD 300039#define DA9062_MAX_POLLING_MS_PERIOD 1000040#define DA9062_MIN_POLLING_MS_PERIOD 100041 42#define DA9062_MILLI_CELSIUS(t) ((t) * 1000)43 44static unsigned int pp_tmp = DA9062_DEFAULT_POLLING_MS_PERIOD;45 46struct da9062_thermal_config {47 const char *name;48};49 50struct da9062_thermal {51 struct da9062 *hw;52 struct delayed_work work;53 struct thermal_zone_device *zone;54 struct mutex lock; /* protection for da9062_thermal temperature */55 int temperature;56 int irq;57 const struct da9062_thermal_config *config;58 struct device *dev;59};60 61static void da9062_thermal_poll_on(struct work_struct *work)62{63 struct da9062_thermal *thermal = container_of(work,64 struct da9062_thermal,65 work.work);66 unsigned long delay;67 unsigned int val;68 int ret;69 70 /* clear E_TEMP */71 ret = regmap_write(thermal->hw->regmap,72 DA9062AA_EVENT_B,73 DA9062AA_E_TEMP_MASK);74 if (ret < 0) {75 dev_err(thermal->dev,76 "Cannot clear the TJUNC temperature status\n");77 goto err_enable_irq;78 }79 80 /* Now read E_TEMP again: it is acting like a status bit.81 * If over-temperature, then this status will be true.82 * If not over-temperature, this status will be false.83 */84 ret = regmap_read(thermal->hw->regmap,85 DA9062AA_EVENT_B,86 &val);87 if (ret < 0) {88 dev_err(thermal->dev,89 "Cannot check the TJUNC temperature status\n");90 goto err_enable_irq;91 }92 93 if (val & DA9062AA_E_TEMP_MASK) {94 mutex_lock(&thermal->lock);95 thermal->temperature = DA9062_MILLI_CELSIUS(125);96 mutex_unlock(&thermal->lock);97 thermal_zone_device_update(thermal->zone,98 THERMAL_EVENT_UNSPECIFIED);99 100 /*101 * pp_tmp is between 1s and 10s, so we can round the jiffies102 */103 delay = round_jiffies(msecs_to_jiffies(pp_tmp));104 queue_delayed_work(system_freezable_wq, &thermal->work, delay);105 return;106 }107 108 mutex_lock(&thermal->lock);109 thermal->temperature = DA9062_MILLI_CELSIUS(0);110 mutex_unlock(&thermal->lock);111 thermal_zone_device_update(thermal->zone,112 THERMAL_EVENT_UNSPECIFIED);113 114err_enable_irq:115 enable_irq(thermal->irq);116}117 118static irqreturn_t da9062_thermal_irq_handler(int irq, void *data)119{120 struct da9062_thermal *thermal = data;121 122 disable_irq_nosync(thermal->irq);123 queue_delayed_work(system_freezable_wq, &thermal->work, 0);124 125 return IRQ_HANDLED;126}127 128static int da9062_thermal_get_temp(struct thermal_zone_device *z,129 int *temp)130{131 struct da9062_thermal *thermal = thermal_zone_device_priv(z);132 133 mutex_lock(&thermal->lock);134 *temp = thermal->temperature;135 mutex_unlock(&thermal->lock);136 137 return 0;138}139 140static struct thermal_zone_device_ops da9062_thermal_ops = {141 .get_temp = da9062_thermal_get_temp,142};143 144static struct thermal_trip trips[] = {145 { .temperature = DA9062_MILLI_CELSIUS(125), .type = THERMAL_TRIP_HOT },146};147 148static const struct da9062_thermal_config da9062_config = {149 .name = "da9062-thermal",150};151 152static const struct of_device_id da9062_compatible_reg_id_table[] = {153 { .compatible = "dlg,da9062-thermal", .data = &da9062_config },154 { },155};156 157MODULE_DEVICE_TABLE(of, da9062_compatible_reg_id_table);158 159static int da9062_thermal_probe(struct platform_device *pdev)160{161 struct da9062 *chip = dev_get_drvdata(pdev->dev.parent);162 struct da9062_thermal *thermal;163 const struct of_device_id *match;164 int ret = 0;165 166 match = of_match_node(da9062_compatible_reg_id_table,167 pdev->dev.of_node);168 if (!match)169 return -ENXIO;170 171 if (pdev->dev.of_node) {172 if (!of_property_read_u32(pdev->dev.of_node,173 "polling-delay-passive",174 &pp_tmp)) {175 if (pp_tmp < DA9062_MIN_POLLING_MS_PERIOD ||176 pp_tmp > DA9062_MAX_POLLING_MS_PERIOD) {177 dev_warn(&pdev->dev,178 "Out-of-range polling period %d ms\n",179 pp_tmp);180 pp_tmp = DA9062_DEFAULT_POLLING_MS_PERIOD;181 }182 }183 }184 185 thermal = devm_kzalloc(&pdev->dev, sizeof(struct da9062_thermal),186 GFP_KERNEL);187 if (!thermal) {188 ret = -ENOMEM;189 goto err;190 }191 192 thermal->config = match->data;193 thermal->hw = chip;194 thermal->dev = &pdev->dev;195 196 INIT_DELAYED_WORK(&thermal->work, da9062_thermal_poll_on);197 mutex_init(&thermal->lock);198 199 thermal->zone = thermal_zone_device_register_with_trips(thermal->config->name,200 trips, ARRAY_SIZE(trips), thermal,201 &da9062_thermal_ops, NULL, pp_tmp,202 0);203 if (IS_ERR(thermal->zone)) {204 dev_err(&pdev->dev, "Cannot register thermal zone device\n");205 ret = PTR_ERR(thermal->zone);206 goto err;207 }208 ret = thermal_zone_device_enable(thermal->zone);209 if (ret) {210 dev_err(&pdev->dev, "Cannot enable thermal zone device\n");211 goto err_zone;212 }213 214 dev_dbg(&pdev->dev,215 "TJUNC temperature polling period set at %d ms\n", pp_tmp);216 217 ret = platform_get_irq_byname(pdev, "THERMAL");218 if (ret < 0)219 goto err_zone;220 221 thermal->irq = ret;222 223 ret = request_threaded_irq(thermal->irq, NULL,224 da9062_thermal_irq_handler,225 IRQF_TRIGGER_LOW | IRQF_ONESHOT,226 "THERMAL", thermal);227 if (ret) {228 dev_err(&pdev->dev,229 "Failed to request thermal device IRQ.\n");230 goto err_zone;231 }232 233 platform_set_drvdata(pdev, thermal);234 return 0;235 236err_zone:237 thermal_zone_device_unregister(thermal->zone);238err:239 return ret;240}241 242static void da9062_thermal_remove(struct platform_device *pdev)243{244 struct da9062_thermal *thermal = platform_get_drvdata(pdev);245 246 free_irq(thermal->irq, thermal);247 cancel_delayed_work_sync(&thermal->work);248 thermal_zone_device_unregister(thermal->zone);249}250 251static struct platform_driver da9062_thermal_driver = {252 .probe = da9062_thermal_probe,253 .remove_new = da9062_thermal_remove,254 .driver = {255 .name = "da9062-thermal",256 .of_match_table = da9062_compatible_reg_id_table,257 },258};259 260module_platform_driver(da9062_thermal_driver);261 262MODULE_AUTHOR("Steve Twiss");263MODULE_DESCRIPTION("Thermal TJUNC device driver for Dialog DA9062 and DA9061");264MODULE_LICENSE("GPL");265MODULE_ALIAS("platform:da9062-thermal");266