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-rw-r--r--drivers/thermal/max77620_thermal.c166
1 files changed, 166 insertions, 0 deletions
diff --git a/drivers/thermal/max77620_thermal.c b/drivers/thermal/max77620_thermal.c
new file mode 100644
index 000000000000..83905ff46e40
--- /dev/null
+++ b/drivers/thermal/max77620_thermal.c
@@ -0,0 +1,166 @@
+/*
+ * Junction temperature thermal driver for Maxim Max77620.
+ *
+ * Copyright (c) 2016, NVIDIA CORPORATION. All rights reserved.
+ *
+ * Author: Laxman Dewangan <ldewangan@nvidia.com>
+ * Mallikarjun Kasoju <mkasoju@nvidia.com>
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms and conditions of the GNU General Public License,
+ * version 2, as published by the Free Software Foundation.
+ */
+
+#include <linux/irq.h>
+#include <linux/interrupt.h>
+#include <linux/mfd/max77620.h>
+#include <linux/module.h>
+#include <linux/of.h>
+#include <linux/platform_device.h>
+#include <linux/regmap.h>
+#include <linux/slab.h>
+#include <linux/thermal.h>
+
+#define MAX77620_NORMAL_OPERATING_TEMP 100000
+#define MAX77620_TJALARM1_TEMP 120000
+#define MAX77620_TJALARM2_TEMP 140000
+
+struct max77620_therm_info {
+ struct device *dev;
+ struct regmap *rmap;
+ struct thermal_zone_device *tz_device;
+ int irq_tjalarm1;
+ int irq_tjalarm2;
+};
+
+/**
+ * max77620_thermal_read_temp: Read PMIC die temperatue.
+ * @data: Device specific data.
+ * temp: Temperature in millidegrees Celsius
+ *
+ * The actual temperature of PMIC die is not available from PMIC.
+ * PMIC only tells the status if it has crossed or not the threshold level
+ * of 120degC or 140degC.
+ * If threshold has not been crossed then assume die temperature as 100degC
+ * else 120degC or 140deG based on the PMIC die temp threshold status.
+ *
+ * Return 0 on success otherwise error number to show reason of failure.
+ */
+
+static int max77620_thermal_read_temp(void *data, int *temp)
+{
+ struct max77620_therm_info *mtherm = data;
+ unsigned int val;
+ int ret;
+
+ ret = regmap_read(mtherm->rmap, MAX77620_REG_STATLBT, &val);
+ if (ret < 0) {
+ dev_err(mtherm->dev, "Failed to read STATLBT: %d\n", ret);
+ return ret;
+ }
+
+ if (val & MAX77620_IRQ_TJALRM2_MASK)
+ *temp = MAX77620_TJALARM2_TEMP;
+ else if (val & MAX77620_IRQ_TJALRM1_MASK)
+ *temp = MAX77620_TJALARM1_TEMP;
+ else
+ *temp = MAX77620_NORMAL_OPERATING_TEMP;
+
+ return 0;
+}
+
+static const struct thermal_zone_of_device_ops max77620_thermal_ops = {
+ .get_temp = max77620_thermal_read_temp,
+};
+
+static irqreturn_t max77620_thermal_irq(int irq, void *data)
+{
+ struct max77620_therm_info *mtherm = data;
+
+ if (irq == mtherm->irq_tjalarm1)
+ dev_warn(mtherm->dev, "Junction Temp Alarm1(120C) occurred\n");
+ else if (irq == mtherm->irq_tjalarm2)
+ dev_crit(mtherm->dev, "Junction Temp Alarm2(140C) occurred\n");
+
+ thermal_zone_device_update(mtherm->tz_device,
+ THERMAL_EVENT_UNSPECIFIED);
+
+ return IRQ_HANDLED;
+}
+
+static int max77620_thermal_probe(struct platform_device *pdev)
+{
+ struct max77620_therm_info *mtherm;
+ int ret;
+
+ mtherm = devm_kzalloc(&pdev->dev, sizeof(*mtherm), GFP_KERNEL);
+ if (!mtherm)
+ return -ENOMEM;
+
+ mtherm->irq_tjalarm1 = platform_get_irq(pdev, 0);
+ mtherm->irq_tjalarm2 = platform_get_irq(pdev, 1);
+ if ((mtherm->irq_tjalarm1 < 0) || (mtherm->irq_tjalarm2 < 0)) {
+ dev_err(&pdev->dev, "Alarm irq number not available\n");
+ return -EINVAL;
+ }
+
+ pdev->dev.of_node = pdev->dev.parent->of_node;
+
+ mtherm->dev = &pdev->dev;
+ mtherm->rmap = dev_get_regmap(pdev->dev.parent, NULL);
+ if (!mtherm->rmap) {
+ dev_err(&pdev->dev, "Failed to get parent regmap\n");
+ return -ENODEV;
+ }
+
+ mtherm->tz_device = devm_thermal_zone_of_sensor_register(&pdev->dev, 0,
+ mtherm, &max77620_thermal_ops);
+ if (IS_ERR(mtherm->tz_device)) {
+ ret = PTR_ERR(mtherm->tz_device);
+ dev_err(&pdev->dev, "Failed to register thermal zone: %d\n",
+ ret);
+ return ret;
+ }
+
+ ret = devm_request_threaded_irq(&pdev->dev, mtherm->irq_tjalarm1, NULL,
+ max77620_thermal_irq,
+ IRQF_ONESHOT | IRQF_SHARED,
+ dev_name(&pdev->dev), mtherm);
+ if (ret < 0) {
+ dev_err(&pdev->dev, "Failed to request irq1: %d\n", ret);
+ return ret;
+ }
+
+ ret = devm_request_threaded_irq(&pdev->dev, mtherm->irq_tjalarm2, NULL,
+ max77620_thermal_irq,
+ IRQF_ONESHOT | IRQF_SHARED,
+ dev_name(&pdev->dev), mtherm);
+ if (ret < 0) {
+ dev_err(&pdev->dev, "Failed to request irq2: %d\n", ret);
+ return ret;
+ }
+
+ platform_set_drvdata(pdev, mtherm);
+
+ return 0;
+}
+
+static struct platform_device_id max77620_thermal_devtype[] = {
+ { .name = "max77620-thermal", },
+ {},
+};
+
+static struct platform_driver max77620_thermal_driver = {
+ .driver = {
+ .name = "max77620-thermal",
+ },
+ .probe = max77620_thermal_probe,
+ .id_table = max77620_thermal_devtype,
+};
+
+module_platform_driver(max77620_thermal_driver);
+
+MODULE_DESCRIPTION("Max77620 Junction temperature Thermal driver");
+MODULE_AUTHOR("Laxman Dewangan <ldewangan@nvidia.com>");
+MODULE_AUTHOR("Mallikarjun Kasoju <mkasoju@nvidia.com>");
+MODULE_LICENSE("GPL v2");