iio: adc: axp20x_adc: fix charging current reporting on AXP22x

commit 92beafb76a31bdc02649eb44e93a8e4f4cfcdbe8 upstream.

Both the charging and discharging currents on AXP22x are stored as
12-bit integers, in accordance with the datasheet.
It's also confirmed by vendor BSP (axp20x_adc.c:axp22_icharge_to_mA).

The scale factor of 0.5 is never mentioned in datasheet, nor in the
vendor source code. I think it was here to compensate for
erroneous addition bit in register width.

Tested on custom A40i+AXP221s board with external ammeter as
a reference.

Fixes: 0e34d5de961d ("iio: adc: add support for X-Powers AXP20X and AXP22X PMICs ADCs")
Signed-off-by: Evgeny Boger <boger@wirenboard.com>
Acked-by: Chen-Yu Tsai <wens@csie.org>
Link: https://lore.kernel.org/r/20211116213746.264378-1-boger@wirenboard.com
Cc: <Stable@vger.kernel.org>
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This commit is contained in:
Evgeny Boger 2021-11-17 00:37:46 +03:00 committed by Greg Kroah-Hartman
parent e5f8403cc8
commit e2471d25b6

View File

@ -224,19 +224,8 @@ static int axp22x_adc_raw(struct iio_dev *indio_dev,
struct iio_chan_spec const *chan, int *val)
{
struct axp20x_adc_iio *info = iio_priv(indio_dev);
int size;
/*
* N.B.: Unlike the Chinese datasheets tell, the charging current is
* stored on 12 bits, not 13 bits. Only discharging current is on 13
* bits.
*/
if (chan->type == IIO_CURRENT && chan->channel == AXP22X_BATT_DISCHRG_I)
size = 13;
else
size = 12;
*val = axp20x_read_variable_width(info->regmap, chan->address, size);
*val = axp20x_read_variable_width(info->regmap, chan->address, 12);
if (*val < 0)
return *val;
@ -329,9 +318,8 @@ static int axp22x_adc_scale(struct iio_chan_spec const *chan, int *val,
return IIO_VAL_INT_PLUS_MICRO;
case IIO_CURRENT:
*val = 0;
*val2 = 500000;
return IIO_VAL_INT_PLUS_MICRO;
*val = 1;
return IIO_VAL_INT;
case IIO_TEMP:
*val = 100;