>From ADC reference manual the software is allowed to write the control bit ADDIS of the ADC_CR register only if the ADC is enabled. Return immediately from stm32h7_adc_disable() if ADC is already disabled. Signed-off-by: Olivier Moysan <olivier.moysan@xxxxxxxxxxx> --- drivers/iio/adc/stm32-adc.c | 3 +++ 1 file changed, 3 insertions(+) diff --git a/drivers/iio/adc/stm32-adc.c b/drivers/iio/adc/stm32-adc.c index a68ecbda6480..80e333f65ddd 100644 --- a/drivers/iio/adc/stm32-adc.c +++ b/drivers/iio/adc/stm32-adc.c @@ -876,6 +876,9 @@ static void stm32h7_adc_disable(struct iio_dev *indio_dev) int ret; u32 val; + if (!(stm32_adc_readl(adc, STM32H7_ADC_CR) & STM32H7_ADEN)) + return; + /* Disable ADC and wait until it's effectively disabled */ stm32_adc_set_bits(adc, STM32H7_ADC_CR, STM32H7_ADDIS); ret = stm32_adc_readl_poll_timeout(STM32H7_ADC_CR, val, -- 2.25.1
