RE: [PATCH rtw-next v7 2/3] wifi: rtw88: rtw8822c: Convert DAC IQ calibration path to signed math

[Ping-Ke Shih <pkshih@realtek.com>]

Arsenii Pashchenko <ulijg308@gmail.com> wrote:
> Convert the temporary stack arrays 'iv' and 'qv' from u32 to s32.
> Update all internal function signatures to accept s32 pointers and
> handle signed values natively.
> 
> Use sign_extend32() combined with FIELD_GET_SIGNED() to properly interpret
> the 10-bit hardware values as signed integers. This allows flattening
> the complex nested unsigned boundary conditions in
> rtw8822c_dac_iq_check() into a simple amplitude boundary check. Ensure
> rtw8822c_dac_iq_offset() properly maps the signed average back to a
> 10-bit unsigned format expected by the hardware registers via GENMASK().
> 
> Signed-off-by: Arsenii Pashchenko <ulijg308@gmail.com>

[...]

> -static void rtw8822c_dac_iq_offset(struct rtw_dev *rtwdev, u32 *vec, u32 *val)
> +static u32 rtw8822c_dac_iq_offset(struct rtw_dev *rtwdev, s32 *vec)
>  {
> -       u32 p, m, t, i;
> +       s32 sum = 0;
> +       s32 avg;
> +       u32 i;
> 
> -       m = 0;
> -       p = 0;
> -       for (i = 10; i < DACK_SN_8822C - 10; i++) {
> -               if (vec[i] > 0x200)
> -                       m = (0x400 - vec[i]) + m;
> -               else
> -                       p = vec[i] + p;
> -       }
> +       for (i = 10; i < DACK_SN_8822C - 10; i++)
> +               sum += vec[i];
> 
> -       if (p > m) {
> -               t = p - m;
> -               t = t / (DACK_SN_8822C - 20);
> -       } else {
> -               t = m - p;
> -               t = t / (DACK_SN_8822C - 20);
> -               if (t != 0x0)
> -                       t = 0x400 - t;
> -       }
> +       avg = sum / (DACK_SN_8822C - 20);
> 
> -       *val = t;
> +       /* Map the signed average back to a 10-bit hardware format.
> +        * Example: avg = -1, returns 0x3FF (signed 10-bit value)
> +        */

The first line of comment block should be empty, like

/*
 * comment start here.
 * second.
 */

> +       return avg & GENMASK(9, 0);
>  }
> 
>  static u32 rtw8822c_get_path_write_addr(u8 path)