staging:iio:ad7298: Rework regulator handling

Rework the regulator handling of the driver to match more closely what we do in
other drivers. Make the regulator non-optional if a external reference is used.
Also dispose the option of specifying the reference voltage via platform data.

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 2012-11-15 13:15:00 +00:00 committed by Jonathan Cameron
parent ca654638f2
commit 2e33460098
2 changed files with 31 additions and 25 deletions

View File

@ -26,19 +26,17 @@
#define RES_MASK(bits) ((1 << (bits)) - 1)
/*
* TODO: struct ad7298_platform_data needs to go into include/linux/iio
*/
/**
* struct ad7298_platform_data - Platform data for the ad7298 ADC driver
* @ext_ref: Whether to use an external reference voltage.
**/
struct ad7298_platform_data {
/* External Vref voltage applied */
u16 vref_mv;
bool ext_ref;
};
struct ad7298_state {
struct spi_device *spi;
struct regulator *reg;
u16 int_vref_mv;
unsigned ext_ref;
struct spi_transfer ring_xfer[10];
struct spi_transfer scan_single_xfer[3];

View File

@ -130,7 +130,7 @@ static int ad7298_read_raw(struct iio_dev *indio_dev,
{
int ret;
struct ad7298_state *st = iio_priv(indio_dev);
unsigned int scale_uv;
int scale_mv;
switch (m) {
case IIO_CHAN_INFO_RAW:
@ -155,10 +155,17 @@ static int ad7298_read_raw(struct iio_dev *indio_dev,
case IIO_CHAN_INFO_SCALE:
switch (chan->type) {
case IIO_VOLTAGE:
scale_uv = (st->int_vref_mv * 1000) >> AD7298_BITS;
*val = scale_uv / 1000;
*val2 = (scale_uv % 1000) * 1000;
return IIO_VAL_INT_PLUS_MICRO;
if (st->ext_ref) {
scale_mv = regulator_get_voltage(st->reg);
if (scale_mv < 0)
return scale_mv;
scale_mv /= 1000;
} else {
scale_mv = AD7298_INTREF_mV;
}
*val = scale_mv;
*val2 = chan->scan_type.realbits;
return IIO_VAL_FRACTIONAL_LOG2;
case IIO_TEMP:
*val = 1;
*val2 = 0;
@ -180,16 +187,23 @@ static int __devinit ad7298_probe(struct spi_device *spi)
{
struct ad7298_platform_data *pdata = spi->dev.platform_data;
struct ad7298_state *st;
int ret;
struct iio_dev *indio_dev = iio_device_alloc(sizeof(*st));
int ret;
if (indio_dev == NULL)
return -ENOMEM;
st = iio_priv(indio_dev);
st->reg = regulator_get(&spi->dev, "vcc");
if (!IS_ERR(st->reg)) {
if (pdata && pdata->ext_ref)
st->ext_ref = AD7298_EXTREF;
if (st->ext_ref) {
st->reg = regulator_get(&spi->dev, "vref");
if (IS_ERR(st->reg)) {
ret = PTR_ERR(st->reg);
goto error_free;
}
ret = regulator_enable(st->reg);
if (ret)
goto error_put_reg;
@ -222,13 +236,6 @@ static int __devinit ad7298_probe(struct spi_device *spi)
spi_message_add_tail(&st->scan_single_xfer[1], &st->scan_single_msg);
spi_message_add_tail(&st->scan_single_xfer[2], &st->scan_single_msg);
if (pdata && pdata->vref_mv) {
st->int_vref_mv = pdata->vref_mv;
st->ext_ref = AD7298_EXTREF;
} else {
st->int_vref_mv = AD7298_INTREF_mV;
}
ret = ad7298_register_ring_funcs_and_init(indio_dev);
if (ret)
goto error_disable_reg;
@ -242,11 +249,12 @@ static int __devinit ad7298_probe(struct spi_device *spi)
error_cleanup_ring:
ad7298_ring_cleanup(indio_dev);
error_disable_reg:
if (!IS_ERR(st->reg))
if (st->ext_ref)
regulator_disable(st->reg);
error_put_reg:
if (!IS_ERR(st->reg))
if (st->ext_ref)
regulator_put(st->reg);
error_free:
iio_device_free(indio_dev);
return ret;
@ -259,7 +267,7 @@ static int __devexit ad7298_remove(struct spi_device *spi)
iio_device_unregister(indio_dev);
ad7298_ring_cleanup(indio_dev);
if (!IS_ERR(st->reg)) {
if (st->ext_ref) {
regulator_disable(st->reg);
regulator_put(st->reg);
}