staging:iio:ad7291: Rework regulator handling

Add platform_data for the driver which allows to specify whether an external
reference voltage is used or not. It is not possible to use the return value of
regulator_get() for this since the regulator framework is able to return a dummy
regulator in case no regulator has been specified. In this case the driver will
always get a valid regulator, no matter if it has been specified or not.  Also
make the regulator non-optional if platform_data states that an external
reference voltage should be used.

Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>
This commit is contained in:
Lars-Peter Clausen 2013-06-14 16:58:00 +01:00 committed by Jonathan Cameron
parent 88198d2b42
commit 1df9d1d4a1
2 changed files with 35 additions and 15 deletions

View File

@ -21,6 +21,8 @@
#include <linux/iio/sysfs.h>
#include <linux/iio/events.h>
#include "ad7291.h"
/*
* Simplified handling
*
@ -76,7 +78,6 @@
struct ad7291_chip_info {
struct i2c_client *client;
struct regulator *reg;
u16 int_vref_mv;
u16 command;
u16 c_mask; /* Active voltage channels for events */
struct mutex state_lock;
@ -445,7 +446,15 @@ static int ad7291_read_raw(struct iio_dev *indio_dev,
case IIO_CHAN_INFO_SCALE:
switch (chan->type) {
case IIO_VOLTAGE:
*val = chip->int_vref_mv;
if (chip->reg) {
int vref;
vref = regulator_get_voltage(chip->reg);
if (vref < 0)
return vref;
*val = vref / 1000;
} else {
*val = 2500;
}
*val2 = AD7291_BITS;
return IIO_VAL_FRACTIONAL_LOG2;
case IIO_TEMP:
@ -513,9 +522,10 @@ static const struct iio_info ad7291_info = {
static int ad7291_probe(struct i2c_client *client,
const struct i2c_device_id *id)
{
struct ad7291_platform_data *pdata = client->dev.platform_data;
struct ad7291_chip_info *chip;
struct iio_dev *indio_dev;
int ret = 0, voltage_uv = 0;
int ret = 0;
indio_dev = iio_device_alloc(sizeof(*chip));
if (indio_dev == NULL) {
@ -524,12 +534,14 @@ static int ad7291_probe(struct i2c_client *client,
}
chip = iio_priv(indio_dev);
chip->reg = regulator_get(&client->dev, "vcc");
if (!IS_ERR(chip->reg)) {
if (pdata && pdata->use_external_ref) {
chip->reg = regulator_get(&client->dev, "vref");
if (IS_ERR(chip->reg))
goto error_free;
ret = regulator_enable(chip->reg);
if (ret)
goto error_put_reg;
voltage_uv = regulator_get_voltage(chip->reg);
}
mutex_init(&chip->state_lock);
@ -542,12 +554,8 @@ static int ad7291_probe(struct i2c_client *client,
AD7291_T_SENSE_MASK | /* Tsense always enabled */
AD7291_ALERT_POLARITY; /* set irq polarity low level */
if (voltage_uv) {
chip->int_vref_mv = voltage_uv / 1000;
if (pdata && pdata->use_external_ref)
chip->command |= AD7291_EXT_REF;
} else {
chip->int_vref_mv = 2500; /* Build-in ref */
}
indio_dev->name = id->name;
indio_dev->channels = ad7291_channels;
@ -590,12 +598,12 @@ error_unreg_irq:
if (client->irq)
free_irq(client->irq, indio_dev);
error_disable_reg:
if (!IS_ERR(chip->reg))
if (chip->reg)
regulator_disable(chip->reg);
error_put_reg:
if (!IS_ERR(chip->reg))
if (chip->reg)
regulator_put(chip->reg);
error_free:
iio_device_free(indio_dev);
error_ret:
return ret;
@ -611,7 +619,7 @@ static int ad7291_remove(struct i2c_client *client)
if (client->irq)
free_irq(client->irq, indio_dev);
if (!IS_ERR(chip->reg)) {
if (chip->reg) {
regulator_disable(chip->reg);
regulator_put(chip->reg);
}

View File

@ -0,0 +1,12 @@
#ifndef __IIO_AD7291_H__
#define __IIO_AD7291_H__
/**
* struct ad7291_platform_data - AD7291 platform data
* @use_external_ref: Whether to use an external or internal reference voltage
*/
struct ad7291_platform_data {
bool use_external_ref;
};
#endif