RE: [PATCH 1/4] wifi: rtw88: rtw8822c: convert DAC IQ buffers and signatures to s32

[Ping-Ke Shih]

Arsenii Pashchenko <ulijg308@xxxxxxxxx> wrote:
> Prepare the DAC IQ calibration path for signed math by converting the
> temporary stack arrays 'iv' and 'qv' from u32 to s32. Update all
> internal function signatures to accept s32 pointers.
> 
> To guarantee bisectability, wrap the existing unsigned logic in
> temporary casts to u32. This maintains identical mathematical behavior
> and avoids any compiler sign-compare warnings.
> 
> Signed-off-by: Arsenii Pashchenko <ulijg308@xxxxxxxxx>
> ---
>  drivers/net/wireless/realtek/rtw88/rtw8822c.c | 49 +++++++++++--------
>  1 file changed, 28 insertions(+), 21 deletions(-)
> 
> diff --git a/drivers/net/wireless/realtek/rtw88/rtw8822c.c
> b/drivers/net/wireless/realtek/rtw88/rtw8822c.c
> index 244c80264..896e3e7b9 100644
> --- a/drivers/net/wireless/realtek/rtw88/rtw8822c.c
> +++ b/drivers/net/wireless/realtek/rtw88/rtw8822c.c
> @@ -153,9 +153,12 @@ static void rtw8822c_dac_restore_reg(struct rtw_dev *rtwdev,
>         }
>  }
> 
> -static void rtw8822c_rf_minmax_cmp(struct rtw_dev *rtwdev, u32 value,
> -                                  u32 *min, u32 *max)
> +static void rtw8822c_rf_minmax_cmp(struct rtw_dev *rtwdev, s32 value_s32,
> +                                  s32 *min_s32, s32 *max_s32)
>  {
> +       u32 value = (u32)value_s32;
> +       u32 *min = (u32 *)min_s32;
> +       u32 *max = (u32 *)max_s32;

blank line

Also, it is possible to avoid all casting from s32 to u32, even just a
transition patch? I guess compiler can silently ignore this, and it'd
be much easier to review. Otherwise, I need to check if you remove
these casting clearly. 

>         if (value >= 0x200) {
>                 if (*min >= 0x200) {
>                         if (*min > value)
> @@ -182,8 +185,10 @@ static void rtw8822c_rf_minmax_cmp(struct rtw_dev *rtwdev, u32 value,
>         }
>  }
> 
> -static void __rtw8822c_dac_iq_sort(struct rtw_dev *rtwdev, u32 *v1, u32 *v2)
> +static void __rtw8822c_dac_iq_sort(struct rtw_dev *rtwdev, s32 *v1_s32, s32 *v2_s32)
>  {
> +       u32 *v1 = (u32 *)v1_s32;
> +       u32 *v2 = (u32 *)v2_s32;

blank line

>         if (*v1 >= 0x200 && *v2 >= 0x200) {
>                 if (*v1 > *v2)
>                         swap(*v1, *v2);

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