hwmon: (adc128d818) Implement mode selection via dt

Implement operation mode selection using the optional 'ti,mode' devicetree
property (see [1]). The ADC128D818 supports four operation modes differing
in the number and type of input readings (see datasheet, sec. 8.4.1), of
which mode 0 is the default.

We only add handling of the 'ti,mode' property here, the driver still
supports nothing else than the default mode 0.

[1] Documentation/devicetree/bindings/hwmon/adc128d818.txt

Signed-off-by: Alexander Koch <mail@alexanderkoch.net>
Acked-by: Michael Hornung <mhornung.linux@gmail.com>
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
This commit is contained in:
Alexander Koch 2017-01-06 11:38:15 +01:00 committed by Guenter Roeck
parent bbcf37d73c
commit a45923c27d

View file

@ -28,6 +28,7 @@
#include <linux/regulator/consumer.h>
#include <linux/mutex.h>
#include <linux/bitops.h>
#include <linux/of.h>
/* Addresses to scan
* The chip also supports addresses 0x35..0x37. Don't scan those addresses
@ -63,6 +64,7 @@ struct adc128_data {
struct regulator *regulator;
int vref; /* Reference voltage in mV */
struct mutex update_lock;
u8 mode; /* Operation mode */
bool valid; /* true if following fields are valid */
unsigned long last_updated; /* In jiffies */
@ -387,6 +389,15 @@ static int adc128_init_client(struct adc128_data *data)
if (err)
return err;
/* Set operation mode, if non-default */
if (data->mode != 0) {
err = i2c_smbus_write_byte_data(client,
ADC128_REG_CONFIG_ADV,
data->mode << 1);
if (err)
return err;
}
/* Start monitoring */
err = i2c_smbus_write_byte_data(client, ADC128_REG_CONFIG, 0x01);
if (err)
@ -433,6 +444,19 @@ static int adc128_probe(struct i2c_client *client,
data->vref = 2560; /* 2.56V, in mV */
}
/* Operation mode is optional and defaults to mode 0 */
if (of_property_read_u8(dev->of_node, "ti,mode", &data->mode) == 0) {
/* Currently only mode 0 supported */
if (data->mode != 0) {
dev_err(dev, "unsupported operation mode %d\n",
data->mode);
err = -EINVAL;
goto error;
}
} else {
data->mode = 0;
}
data->client = client;
i2c_set_clientdata(client, data);
mutex_init(&data->update_lock);