diff mbox series

[1/2] iio: adc: stm32-adc: make safe adc disable

Message ID 20220620154738.801706-2-olivier.moysan@foss.st.com (mailing list archive)
State Accepted
Headers show
Series iio: adc: stm32-adc: add checks on adc state | expand

Commit Message

Olivier Moysan June 20, 2022, 3:47 p.m. UTC
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@foss.st.com>
---
 drivers/iio/adc/stm32-adc.c | 3 +++
 1 file changed, 3 insertions(+)

Comments

Fabrice Gasnier June 21, 2022, 3:38 p.m. UTC | #1
On 6/20/22 17:47, Olivier Moysan wrote:
> 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@foss.st.com>

Hi Olivier,

You can add my:
Reviewed-by: Fabrice Gasnier <fabrice.gasnier@foss.st.com>

Thanks,
Fabrice

> ---
>  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,
diff mbox series

Patch

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,