Re: [PATCH] iio: dac: adi-axi: fix a mistake in axi_dac_ext_info_set()

["Nuno Sá" <noname.nuno@gmail.com>]

Hi Dan,

On Wed, 2024-04-24 at 14:45 +0300, Dan Carpenter wrote:
> The last parameter of these axi_dac_(frequency|scale|phase)_set()
> functions is supposed to be true for TONE_2 and false for TONE_1. The
> bug is the last call where it passes "private - TONE_2".  That
> subtraction is going to be zero/false for TONE_2 and and -1/true for
> TONE_1.  Fix the bug, and re-write it as "private == TONE_2" so it's
> more obvious what is happening.
> 
> Fixes: 4e3949a192e4 ("iio: dac: add support for AXI DAC IP core")
> Signed-off-by: Dan Carpenter <dan.carpenter@linaro.org>
> ---
> This is from code review.  Untested.
> ---

Auch, good catch! Agreed that private == AXI_DAC_*_TONE_2 makes it more
readable.

I guess Jonathan may just squash this in the driver (was pushed this weekend).
Anyways, FWIW:

Reviewed-by: Nuno Sa <nuno.sa@analog.com>

>  drivers/iio/dac/adi-axi-dac.c | 6 +++---
>  1 file changed, 3 insertions(+), 3 deletions(-)
> 
> diff --git a/drivers/iio/dac/adi-axi-dac.c b/drivers/iio/dac/adi-axi-dac.c
> index 9047c5aec0ff..880d83a014a1 100644
> --- a/drivers/iio/dac/adi-axi-dac.c
> +++ b/drivers/iio/dac/adi-axi-dac.c
> @@ -383,15 +383,15 @@ static int axi_dac_ext_info_set(struct iio_backend
> *back, uintptr_t private,
>  	case AXI_DAC_FREQ_TONE_1:
>  	case AXI_DAC_FREQ_TONE_2:
>  		return axi_dac_frequency_set(st, chan, buf, len,
> -					     private - AXI_DAC_FREQ_TONE_1);
> +					     private == AXI_DAC_FREQ_TONE_2);
>  	case AXI_DAC_SCALE_TONE_1:
>  	case AXI_DAC_SCALE_TONE_2:
>  		return axi_dac_scale_set(st, chan, buf, len,
> -					 private - AXI_DAC_SCALE_TONE_1);
> +					 private == AXI_DAC_SCALE_TONE_2);
>  	case AXI_DAC_PHASE_TONE_1:
>  	case AXI_DAC_PHASE_TONE_2:
>  		return axi_dac_phase_set(st, chan, buf, len,
> -					 private - AXI_DAC_PHASE_TONE_2);
> +					 private == AXI_DAC_PHASE_TONE_2);
>  	default:
>  		return -EOPNOTSUPP;
>  	}