From: Paul Cercueil <paul@xxxxxxxxxxxxxxx> commit c91ebcc578e09783cfa4d85c1b437790f140f29a upstream. The reference voltage for the battery is clearly marked as 1.2V in the programming manual. With this fixed, the battery channel now returns correct values. Fixes: a515d6488505 ("IIO: Ingenic JZ47xx: Add support for JZ4770 SoC ADC.") Signed-off-by: Paul Cercueil <paul@xxxxxxxxxxxxxxx> Acked-by: Artur Rojek <contact@xxxxxxxxxxxxxx> Cc: <stable@xxxxxxxxxxxxxxx> Link: https://lore.kernel.org/r/20201104192843.67187-1-paul@xxxxxxxxxxxxxxx Signed-off-by: Jonathan Cameron <Jonathan.Cameron@xxxxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- drivers/iio/adc/ingenic-adc.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) --- a/drivers/iio/adc/ingenic-adc.c +++ b/drivers/iio/adc/ingenic-adc.c @@ -71,7 +71,7 @@ #define JZ4725B_ADC_BATTERY_HIGH_VREF_BITS 10 #define JZ4740_ADC_BATTERY_HIGH_VREF (7500 * 0.986) #define JZ4740_ADC_BATTERY_HIGH_VREF_BITS 12 -#define JZ4770_ADC_BATTERY_VREF 6600 +#define JZ4770_ADC_BATTERY_VREF 1200 #define JZ4770_ADC_BATTERY_VREF_BITS 12 #define JZ_ADC_IRQ_AUX BIT(0)