--- /dev/null
+/*
+ * Thermal device driver for DA9062 and DA9061
+ * Copyright (C) 2017 Dialog Semiconductor
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; either version 2
+ * of the License, or (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ */
+
+/* When over-temperature is reached, an interrupt from the device will be
+ * triggered. Following this event the interrupt will be disabled and
+ * periodic transmission of uevents (HOT trip point) should define the
+ * first level of temperature supervision. It is expected that any final
+ * implementation of the thermal driver will include a .notify() function
+ * to implement these uevents to userspace.
+ *
+ * These uevents are intended to indicate non-invasive temperature control
+ * of the system, where the necessary measures for cooling are the
+ * responsibility of the host software. Once the temperature falls again,
+ * the IRQ is re-enabled so the start of a new over-temperature event can
+ * be detected without constant software monitoring.
+ */
+
+#include <linux/errno.h>
+#include <linux/interrupt.h>
+#include <linux/module.h>
+#include <linux/of.h>
+#include <linux/platform_device.h>
+#include <linux/regmap.h>
+#include <linux/thermal.h>
+#include <linux/workqueue.h>
+
+#include <linux/mfd/da9062/core.h>
+#include <linux/mfd/da9062/registers.h>
+
+/* Minimum, maximum and default polling millisecond periods are provided
+ * here as an example. It is expected that any final implementation to also
+ * include a modification of these settings to match the required
+ * application.
+ */
+#define DA9062_DEFAULT_POLLING_MS_PERIOD 3000
+#define DA9062_MAX_POLLING_MS_PERIOD 10000
+#define DA9062_MIN_POLLING_MS_PERIOD 1000
+
+#define DA9062_MILLI_CELSIUS(t) ((t) * 1000)
+
+struct da9062_thermal_config {
+ const char *name;
+};
+
+struct da9062_thermal {
+ struct da9062 *hw;
+ struct delayed_work work;
+ struct thermal_zone_device *zone;
+ enum thermal_device_mode mode;
+ struct mutex lock; /* protection for da9062_thermal temperature */
+ int temperature;
+ int irq;
+ const struct da9062_thermal_config *config;
+ struct device *dev;
+};
+
+static void da9062_thermal_poll_on(struct work_struct *work)
+{
+ struct da9062_thermal *thermal = container_of(work,
+ struct da9062_thermal,
+ work.work);
+ unsigned long delay;
+ unsigned int val;
+ int ret;
+
+ /* clear E_TEMP */
+ ret = regmap_write(thermal->hw->regmap,
+ DA9062AA_EVENT_B,
+ DA9062AA_E_TEMP_MASK);
+ if (ret < 0) {
+ dev_err(thermal->dev,
+ "Cannot clear the TJUNC temperature status\n");
+ goto err_enable_irq;
+ }
+
+ /* Now read E_TEMP again: it is acting like a status bit.
+ * If over-temperature, then this status will be true.
+ * If not over-temperature, this status will be false.
+ */
+ ret = regmap_read(thermal->hw->regmap,
+ DA9062AA_EVENT_B,
+ &val);
+ if (ret < 0) {
+ dev_err(thermal->dev,
+ "Cannot check the TJUNC temperature status\n");
+ goto err_enable_irq;
+ }
+
+ if (val & DA9062AA_E_TEMP_MASK) {
+ mutex_lock(&thermal->lock);
+ thermal->temperature = DA9062_MILLI_CELSIUS(125);
+ mutex_unlock(&thermal->lock);
+ thermal_zone_device_update(thermal->zone,
+ THERMAL_EVENT_UNSPECIFIED);
+
+ delay = msecs_to_jiffies(thermal->zone->passive_delay);
+ schedule_delayed_work(&thermal->work, delay);
+ return;
+ }
+
+ mutex_lock(&thermal->lock);
+ thermal->temperature = DA9062_MILLI_CELSIUS(0);
+ mutex_unlock(&thermal->lock);
+ thermal_zone_device_update(thermal->zone,
+ THERMAL_EVENT_UNSPECIFIED);
+
+err_enable_irq:
+ enable_irq(thermal->irq);
+}
+
+static irqreturn_t da9062_thermal_irq_handler(int irq, void *data)
+{
+ struct da9062_thermal *thermal = data;
+
+ disable_irq_nosync(thermal->irq);
+ schedule_delayed_work(&thermal->work, 0);
+
+ return IRQ_HANDLED;
+}
+
+static int da9062_thermal_get_mode(struct thermal_zone_device *z,
+ enum thermal_device_mode *mode)
+{
+ struct da9062_thermal *thermal = z->devdata;
+ *mode = thermal->mode;
+ return 0;
+}
+
+static int da9062_thermal_get_trip_type(struct thermal_zone_device *z,
+ int trip,
+ enum thermal_trip_type *type)
+{
+ struct da9062_thermal *thermal = z->devdata;
+
+ switch (trip) {
+ case 0:
+ *type = THERMAL_TRIP_HOT;
+ break;
+ default:
+ dev_err(thermal->dev,
+ "Driver does not support more than 1 trip-wire\n");
+ return -EINVAL;
+ }
+
+ return 0;
+}
+
+static int da9062_thermal_get_trip_temp(struct thermal_zone_device *z,
+ int trip,
+ int *temp)
+{
+ struct da9062_thermal *thermal = z->devdata;
+
+ switch (trip) {
+ case 0:
+ *temp = DA9062_MILLI_CELSIUS(125);
+ break;
+ default:
+ dev_err(thermal->dev,
+ "Driver does not support more than 1 trip-wire\n");
+ return -EINVAL;
+ }
+
+ return 0;
+}
+
+static int da9062_thermal_get_temp(struct thermal_zone_device *z,
+ int *temp)
+{
+ struct da9062_thermal *thermal = z->devdata;
+
+ mutex_lock(&thermal->lock);
+ *temp = thermal->temperature;
+ mutex_unlock(&thermal->lock);
+
+ return 0;
+}
+
+static struct thermal_zone_device_ops da9062_thermal_ops = {
+ .get_temp = da9062_thermal_get_temp,
+ .get_mode = da9062_thermal_get_mode,
+ .get_trip_type = da9062_thermal_get_trip_type,
+ .get_trip_temp = da9062_thermal_get_trip_temp,
+};
+
+static const struct da9062_thermal_config da9062_config = {
+ .name = "da9062-thermal",
+};
+
+static const struct of_device_id da9062_compatible_reg_id_table[] = {
+ { .compatible = "dlg,da9062-thermal", .data = &da9062_config },
+ { },
+};
+
+MODULE_DEVICE_TABLE(of, da9062_compatible_reg_id_table);
+
+static int da9062_thermal_probe(struct platform_device *pdev)
+{
+ struct da9062 *chip = dev_get_drvdata(pdev->dev.parent);
+ struct da9062_thermal *thermal;
+ unsigned int pp_tmp = DA9062_DEFAULT_POLLING_MS_PERIOD;
+ const struct of_device_id *match;
+ int ret = 0;
+
+ match = of_match_node(da9062_compatible_reg_id_table,
+ pdev->dev.of_node);
+ if (!match)
+ return -ENXIO;
+
+ if (pdev->dev.of_node) {
+ if (!of_property_read_u32(pdev->dev.of_node,
+ "polling-delay-passive",
+ &pp_tmp)) {
+ if (pp_tmp < DA9062_MIN_POLLING_MS_PERIOD ||
+ pp_tmp > DA9062_MAX_POLLING_MS_PERIOD) {
+ dev_warn(&pdev->dev,
+ "Out-of-range polling period %d ms\n",
+ pp_tmp);
+ pp_tmp = DA9062_DEFAULT_POLLING_MS_PERIOD;
+ }
+ }
+ }
+
+ thermal = devm_kzalloc(&pdev->dev, sizeof(struct da9062_thermal),
+ GFP_KERNEL);
+ if (!thermal) {
+ ret = -ENOMEM;
+ goto err;
+ }
+
+ thermal->config = match->data;
+ thermal->hw = chip;
+ thermal->mode = THERMAL_DEVICE_ENABLED;
+ thermal->dev = &pdev->dev;
+
+ INIT_DELAYED_WORK(&thermal->work, da9062_thermal_poll_on);
+ mutex_init(&thermal->lock);
+
+ thermal->zone = thermal_zone_device_register(thermal->config->name,
+ 1, 0, thermal,
+ &da9062_thermal_ops, NULL, pp_tmp,
+ 0);
+ if (IS_ERR(thermal->zone)) {
+ dev_err(&pdev->dev, "Cannot register thermal zone device\n");
+ ret = PTR_ERR(thermal->zone);
+ goto err;
+ }
+
+ dev_dbg(&pdev->dev,
+ "TJUNC temperature polling period set at %d ms\n",
+ thermal->zone->passive_delay);
+
+ ret = platform_get_irq_byname(pdev, "THERMAL");
+ if (ret < 0) {
+ dev_err(&pdev->dev, "Failed to get platform IRQ.\n");
+ goto err_zone;
+ }
+ thermal->irq = ret;
+
+ ret = request_threaded_irq(thermal->irq, NULL,
+ da9062_thermal_irq_handler,
+ IRQF_TRIGGER_LOW | IRQF_ONESHOT,
+ "THERMAL", thermal);
+ if (ret) {
+ dev_err(&pdev->dev,
+ "Failed to request thermal device IRQ.\n");
+ goto err_zone;
+ }
+
+ platform_set_drvdata(pdev, thermal);
+ return 0;
+
+err_zone:
+ thermal_zone_device_unregister(thermal->zone);
+err:
+ return ret;
+}
+
+static int da9062_thermal_remove(struct platform_device *pdev)
+{
+ struct da9062_thermal *thermal = platform_get_drvdata(pdev);
+
+ free_irq(thermal->irq, thermal);
+ cancel_delayed_work_sync(&thermal->work);
+ thermal_zone_device_unregister(thermal->zone);
+ return 0;
+}
+
+static struct platform_driver da9062_thermal_driver = {
+ .probe = da9062_thermal_probe,
+ .remove = da9062_thermal_remove,
+ .driver = {
+ .name = "da9062-thermal",
+ .of_match_table = da9062_compatible_reg_id_table,
+ },
+};
+
+module_platform_driver(da9062_thermal_driver);
+
+MODULE_AUTHOR("Steve Twiss");
+MODULE_DESCRIPTION("Thermal TJUNC device driver for Dialog DA9062 and DA9061");
+MODULE_LICENSE("GPL");
+MODULE_ALIAS("platform:da9062-thermal");
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