diff options
Diffstat (limited to 'drivers/thermal/max77620_thermal.c')
| -rw-r--r-- | drivers/thermal/max77620_thermal.c | 166 |
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"); |