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-rw-r--r--drivers/hwmon/Kconfig1
-rw-r--r--drivers/hwmon/ntc_thermistor.c145
2 files changed, 127 insertions, 19 deletions
diff --git a/drivers/hwmon/Kconfig b/drivers/hwmon/Kconfig
index aaa14f4a0f7d..47d2176957a0 100644
--- a/drivers/hwmon/Kconfig
+++ b/drivers/hwmon/Kconfig
@@ -899,6 +899,7 @@ config SENSORS_MCP3021
config SENSORS_NTC_THERMISTOR
tristate "NTC thermistor support"
+ depends on (!OF && !IIO) || (OF && IIO)
help
This driver supports NTC thermistors sensor reading and its
interpretation. The driver can also monitor the temperature and
diff --git a/drivers/hwmon/ntc_thermistor.c b/drivers/hwmon/ntc_thermistor.c
index b5f63f9c0ce1..d399197655e6 100644
--- a/drivers/hwmon/ntc_thermistor.c
+++ b/drivers/hwmon/ntc_thermistor.c
@@ -26,9 +26,16 @@
#include <linux/math64.h>
#include <linux/platform_device.h>
#include <linux/err.h>
+#include <linux/of.h>
+#include <linux/of_device.h>
#include <linux/platform_data/ntc_thermistor.h>
+#include <linux/iio/iio.h>
+#include <linux/iio/machine.h>
+#include <linux/iio/driver.h>
+#include <linux/iio/consumer.h>
+
#include <linux/hwmon.h>
#include <linux/hwmon-sysfs.h>
@@ -37,6 +44,15 @@ struct ntc_compensation {
unsigned int ohm;
};
+static const struct platform_device_id ntc_thermistor_id[] = {
+ { "ncp15wb473", TYPE_NCPXXWB473 },
+ { "ncp18wb473", TYPE_NCPXXWB473 },
+ { "ncp21wb473", TYPE_NCPXXWB473 },
+ { "ncp03wb473", TYPE_NCPXXWB473 },
+ { "ncp15wl333", TYPE_NCPXXWL333 },
+ { },
+};
+
/*
* A compensation table should be sorted by the values of .ohm
* in descending order.
@@ -125,6 +141,92 @@ struct ntc_data {
char name[PLATFORM_NAME_SIZE];
};
+#ifdef CONFIG_OF
+static int ntc_adc_iio_read(struct ntc_thermistor_platform_data *pdata)
+{
+ struct iio_channel *channel = pdata->chan;
+ unsigned int result;
+ int val, ret;
+
+ ret = iio_read_channel_raw(channel, &val);
+ if (ret < 0) {
+ pr_err("read channel() error: %d\n", ret);
+ return ret;
+ }
+
+ /* unit: mV */
+ result = pdata->pullup_uV * val;
+ result >>= 12;
+
+ return result;
+}
+
+static const struct of_device_id ntc_match[] = {
+ { .compatible = "ntc,ncp15wb473",
+ .data = &ntc_thermistor_id[TYPE_NCPXXWB473] },
+ { .compatible = "ntc,ncp18wb473",
+ .data = &ntc_thermistor_id[TYPE_NCPXXWB473] },
+ { .compatible = "ntc,ncp21wb473",
+ .data = &ntc_thermistor_id[TYPE_NCPXXWB473] },
+ { .compatible = "ntc,ncp03wb473",
+ .data = &ntc_thermistor_id[TYPE_NCPXXWB473] },
+ { .compatible = "ntc,ncp15wl333",
+ .data = &ntc_thermistor_id[TYPE_NCPXXWL333] },
+ { },
+};
+MODULE_DEVICE_TABLE(of, ntc_match);
+
+static struct ntc_thermistor_platform_data *
+ntc_thermistor_parse_dt(struct platform_device *pdev)
+{
+ struct iio_channel *chan;
+ struct device_node *np = pdev->dev.of_node;
+ struct ntc_thermistor_platform_data *pdata;
+
+ if (!np)
+ return NULL;
+
+ pdata = devm_kzalloc(&pdev->dev, sizeof(*pdata), GFP_KERNEL);
+ if (!pdata)
+ return ERR_PTR(-ENOMEM);
+
+ chan = iio_channel_get(&pdev->dev, NULL);
+ if (IS_ERR(chan))
+ return ERR_CAST(chan);
+
+ if (of_property_read_u32(np, "pullup-uv", &pdata->pullup_uV))
+ return ERR_PTR(-ENODEV);
+ if (of_property_read_u32(np, "pullup-ohm", &pdata->pullup_ohm))
+ return ERR_PTR(-ENODEV);
+ if (of_property_read_u32(np, "pulldown-ohm", &pdata->pulldown_ohm))
+ return ERR_PTR(-ENODEV);
+
+ if (of_find_property(np, "connected-positive", NULL))
+ pdata->connect = NTC_CONNECTED_POSITIVE;
+ else /* status change should be possible if not always on. */
+ pdata->connect = NTC_CONNECTED_GROUND;
+
+ pdata->chan = chan;
+ pdata->read_uV = ntc_adc_iio_read;
+
+ return pdata;
+}
+static void ntc_iio_channel_release(struct ntc_thermistor_platform_data *pdata)
+{
+ if (pdata->chan)
+ iio_channel_release(pdata->chan);
+}
+#else
+static struct ntc_thermistor_platform_data *
+ntc_thermistor_parse_dt(struct platform_device *pdev)
+{
+ return NULL;
+}
+
+static void ntc_iio_channel_release(struct ntc_thermistor_platform_data *pdata)
+{ }
+#endif
+
static inline u64 div64_u64_safe(u64 dividend, u64 divisor)
{
if (divisor == 0 && dividend == 0)
@@ -259,7 +361,7 @@ static int ntc_thermistor_get_ohm(struct ntc_data *data)
return data->pdata->read_ohm();
if (data->pdata->read_uV) {
- read_uV = data->pdata->read_uV();
+ read_uV = data->pdata->read_uV(data->pdata);
if (read_uV < 0)
return read_uV;
return get_ohm_of_thermistor(data, read_uV);
@@ -311,9 +413,18 @@ static const struct attribute_group ntc_attr_group = {
static int ntc_thermistor_probe(struct platform_device *pdev)
{
+ const struct of_device_id *of_id =
+ of_match_device(of_match_ptr(ntc_match), &pdev->dev);
+ const struct platform_device_id *pdev_id;
+ struct ntc_thermistor_platform_data *pdata;
struct ntc_data *data;
- struct ntc_thermistor_platform_data *pdata = pdev->dev.platform_data;
- int ret = 0;
+ int ret;
+
+ pdata = ntc_thermistor_parse_dt(pdev);
+ if (IS_ERR(pdata))
+ return PTR_ERR(pdata);
+ else if (pdata == NULL)
+ pdata = pdev->dev.platform_data;
if (!pdata) {
dev_err(&pdev->dev, "No platform init data supplied.\n");
@@ -349,11 +460,13 @@ static int ntc_thermistor_probe(struct platform_device *pdev)
if (!data)
return -ENOMEM;
+ pdev_id = of_id ? of_id->data : platform_get_device_id(pdev);
+
data->dev = &pdev->dev;
data->pdata = pdata;
- strlcpy(data->name, pdev->id_entry->name, sizeof(data->name));
+ strlcpy(data->name, pdev_id->name, sizeof(data->name));
- switch (pdev->id_entry->driver_data) {
+ switch (pdev_id->driver_data) {
case TYPE_NCPXXWB473:
data->comp = ncpXXwb473;
data->n_comp = ARRAY_SIZE(ncpXXwb473);
@@ -364,8 +477,7 @@ static int ntc_thermistor_probe(struct platform_device *pdev)
break;
default:
dev_err(&pdev->dev, "Unknown device type: %lu(%s)\n",
- pdev->id_entry->driver_data,
- pdev->id_entry->name);
+ pdev_id->driver_data, pdev_id->name);
return -EINVAL;
}
@@ -384,39 +496,34 @@ static int ntc_thermistor_probe(struct platform_device *pdev)
goto err_after_sysfs;
}
- dev_info(&pdev->dev, "Thermistor %s:%d (type: %s/%lu) successfully probed.\n",
- pdev->name, pdev->id, pdev->id_entry->name,
- pdev->id_entry->driver_data);
+ dev_info(&pdev->dev, "Thermistor type: %s successfully probed.\n",
+ pdev->name);
+
return 0;
err_after_sysfs:
sysfs_remove_group(&data->dev->kobj, &ntc_attr_group);
+ ntc_iio_channel_release(pdata);
return ret;
}
static int ntc_thermistor_remove(struct platform_device *pdev)
{
struct ntc_data *data = platform_get_drvdata(pdev);
+ struct ntc_thermistor_platform_data *pdata = data->pdata;
hwmon_device_unregister(data->hwmon_dev);
sysfs_remove_group(&data->dev->kobj, &ntc_attr_group);
+ ntc_iio_channel_release(pdata);
platform_set_drvdata(pdev, NULL);
return 0;
}
-static const struct platform_device_id ntc_thermistor_id[] = {
- { "ncp15wb473", TYPE_NCPXXWB473 },
- { "ncp18wb473", TYPE_NCPXXWB473 },
- { "ncp21wb473", TYPE_NCPXXWB473 },
- { "ncp03wb473", TYPE_NCPXXWB473 },
- { "ncp15wl333", TYPE_NCPXXWL333 },
- { },
-};
-
static struct platform_driver ntc_thermistor_driver = {
.driver = {
.name = "ntc-thermistor",
.owner = THIS_MODULE,
+ .of_match_table = of_match_ptr(ntc_match),
},
.probe = ntc_thermistor_probe,
.remove = ntc_thermistor_remove,