[PATCH 4/8] hwmon: Add support for Azoteq IQS620AT temperature sensor

Jeff LaBundy
2019-10-21T04:19:19Z

This patch adds support for the Azoteq IQS620AT temperature sensor,
capable of reporting its absolute die temperature.

Signed-off-by: Jeff LaBundy <jeff@labundy.com>
---
drivers/hwmon/Kconfig | 12 +++++-
drivers/hwmon/Makefile | 1 +
drivers/hwmon/iqs620at-temp.c | 96 +++++++++++++++++++++++++++++++++++++++++++
3 files changed, 108 insertions(+), 1 deletion(-)
create mode 100644 drivers/hwmon/iqs620at-temp.c

diff --git a/drivers/hwmon/Kconfig b/drivers/hwmon/Kconfig
index 13a6b4a..3e56be6 100644
--- a/drivers/hwmon/Kconfig
+++ b/drivers/hwmon/Kconfig
@@ -385,6 +385,16 @@ config SENSORS_ATXP1
This driver can also be built as a module. If so, the module
will be called atxp1.

+config SENSORS_IQS620AT
+ tristate "Azoteq IQS620AT temperature sensor"
+ depends on MFD_IQS62X
+ help
+ Say Y here if you want to build support for the Azoteq IQS620AT
+ temperature sensor.
+
+ To compile this driver as a module, choose M here: the module
+ will be called iqs620at-temp.
+
config SENSORS_DS620
tristate "Dallas Semiconductor DS620"
depends on I2C
@@ -1593,7 +1603,7 @@ config SENSORS_ADS7871

config SENSORS_AMC6821
tristate "Texas Instruments AMC6821"
- depends on I2C
+ depends on I2C
help
If you say yes here you get support for the Texas Instruments
AMC6821 hardware monitoring chips.
diff --git a/drivers/hwmon/Makefile b/drivers/hwmon/Makefile
index 40c036e..2360add 100644
--- a/drivers/hwmon/Makefile
+++ b/drivers/hwmon/Makefile
@@ -83,6 +83,7 @@ obj-$(CONFIG_SENSORS_IIO_HWMON) += iio_hwmon.o
obj-$(CONFIG_SENSORS_INA209) += ina209.o
obj-$(CONFIG_SENSORS_INA2XX) += ina2xx.o
obj-$(CONFIG_SENSORS_INA3221) += ina3221.o
+obj-$(CONFIG_SENSORS_IQS620AT) += iqs620at-temp.o
obj-$(CONFIG_SENSORS_IT87) += it87.o
obj-$(CONFIG_SENSORS_JC42) += jc42.o
obj-$(CONFIG_SENSORS_K8TEMP) += k8temp.o
diff --git a/drivers/hwmon/iqs620at-temp.c b/drivers/hwmon/iqs620at-temp.c
new file mode 100644
index 0000000..0af49b6
--- /dev/null
+++ b/drivers/hwmon/iqs620at-temp.c
@@ -0,0 +1,96 @@
+// SPDX-License-Identifier: GPL-2.0+
+/*
+ * Azoteq IQS620AT Temperature Sensor
+ *
+ * Copyright (C) 2019
+ * Author: Jeff LaBundy <jeff@labundy.com>
+ */
+
+#include <linux/device.h>
+#include <linux/err.h>
+#include <linux/hwmon.h>
+#include <linux/kernel.h>
+#include <linux/mfd/iqs62x.h>
+#include <linux/module.h>
+#include <linux/platform_device.h>
+#include <linux/regmap.h>
+
+#define IQS620_TEMP_UI_OUT 0x1A
+
+static umode_t iqs620_temp_is_visible(const void *drvdata,
+ enum hwmon_sensor_types type,
+ u32 attr, int channel)
+{
+ if (type != hwmon_temp || attr != hwmon_temp_input)
+ return 0;
+
+ return 0444;
+}
+
+static int iqs620_temp_read(struct device *dev, enum hwmon_sensor_types type,
+ u32 attr, int channel, long *val)
+{
+ struct iqs62x_core *iqs62x = dev_get_drvdata(dev);
+ int error;
+ __le16 val_buf;
+
+ if (type != hwmon_temp || attr != hwmon_temp_input)
+ return -EINVAL;
+
+ error = regmap_raw_read(iqs62x->map, IQS620_TEMP_UI_OUT, &val_buf,
+ sizeof(val_buf));
+ if (error)
+ return error;
+
+ *val = (le16_to_cpu(val_buf) - 100) * 1000;
+
+ return 0;
+}
+
+static const struct hwmon_ops iqs620_temp_ops = {
+ .is_visible = iqs620_temp_is_visible,
+ .read = iqs620_temp_read,
+};
+
+static const struct hwmon_channel_info *iqs620_temp_channel_info[] = {
+ HWMON_CHANNEL_INFO(chip, HWMON_C_REGISTER_TZ),
+ HWMON_CHANNEL_INFO(temp, HWMON_T_INPUT),
+ NULL
+};
+
+static const struct hwmon_chip_info iqs620_temp_chip_info = {
+ .ops = &iqs620_temp_ops,
+ .info = iqs620_temp_channel_info,
+};
+
+static int iqs620_temp_probe(struct platform_device *pdev)
+{
+ struct iqs62x_core *iqs62x = dev_get_drvdata(pdev->dev.parent);
+ struct device *hdev;
+ int error = 0;
+
+ hdev = devm_hwmon_device_register_with_info(&pdev->dev,
+ iqs62x->dev_desc->dev_name,
+ iqs62x,
+ &iqs620_temp_chip_info,
+ NULL);
+ if (IS_ERR(hdev)) {
+ error = PTR_ERR(hdev);
+ dev_err(&pdev->dev, "Failed to register device: %d\n", error);
+ }
+
+ return error;
+}
+
+static struct platform_driver iqs620_temp_platform_driver = {
+ .driver = {
+ .name = IQS620_DRV_NAME_TEMP,
+ },
+ .probe = iqs620_temp_probe,
+};
+module_platform_driver(iqs620_temp_platform_driver);
+
+MODULE_AUTHOR("Jeff LaBundy <jeff@labundy.com>");
+MODULE_DESCRIPTION("Azoteq IQS620AT Temperature Sensor");
+MODULE_LICENSE("GPL");
+MODULE_ALIAS("platform:" IQS620_DRV_NAME_TEMP);
--
2.7.4