Re: [PATCH] iio: adc: adi-axi-adc: fix ad7606_bus_reg_read()

[David Lechner <dlechner@baylibre.com>]

On 5/30/25 2:09 PM, David Lechner wrote:
> Mask the value read before returning it. The value read over the
> parallel bus via the AXI ADC IP block contains both the address and
> the data, but callers expect val to only contain the data.
> 
> Cc: stable@vger.kernel.org
> Fixes: 79c47485e438 ("iio: adc: adi-axi-adc: add support for AD7606 register writing")
> Signed-off-by: David Lechner <dlechner@baylibre.com>
> ---
>  drivers/iio/adc/adi-axi-adc.c | 3 +++
>  1 file changed, 3 insertions(+)
> 
> diff --git a/drivers/iio/adc/adi-axi-adc.c b/drivers/iio/adc/adi-axi-adc.c
> index cf942c043457ccea49207c3900153ee371b3774f..d4759a98b4062bc25ea088e3868806e82db03e8d 100644
> --- a/drivers/iio/adc/adi-axi-adc.c
> +++ b/drivers/iio/adc/adi-axi-adc.c
> @@ -457,6 +457,9 @@ static int ad7606_bus_reg_read(struct iio_backend *back, u32 reg, u32 *val)
>  	axi_adc_raw_write(back, addr);
>  	axi_adc_raw_read(back, val);
>  
> +	/* Register value is 8 bits. Remove address bits. */
> +	*val &= 0xFF;

I just found out that there is ADI_AXI_REG_VALUE_MASK we can use
here instead of 0xFF.

> +
>  	/* Write 0x0 on the bus to get back to ADC mode */
>  	axi_adc_raw_write(back, 0);
>  
> 
> ---
> base-commit: 7cdfbc0113d087348b8e65dd79276d0f57b89a10
> change-id: 20250530-iio-adc-adi-axi-adc-fix-ad7606_bus_reg_read-f2bbb503db8b
> 
> Best regards,