> -----Original Message-----
> From: Bitterblue Smith <rtl8821cerfe2@xxxxxxxxx>
> Sent: Monday, July 10, 2023 2:38 AM
> To: linux-wireless@xxxxxxxxxxxxxxx
> Cc: Jes Sorensen <Jes.Sorensen@xxxxxxxxx>; Ping-Ke Shih <pkshih@xxxxxxxxxxx>
> Subject: [PATCH RFC] wifi: rtl8xxxu: Fix the TX power of RTL8192CU, RTL8723AU
>
> Don't subtract 1 from the power index. This was added in commit
> 2fc0b8e5a17d ("rtl8xxxu: Add TX power base values for gen1 parts")
> for unknown reasons. The vendor drivers don't do this.
>
> Also correct the calculations of values written to
> REG_OFDM0_X{C,D}_TX_IQ_IMBALANCE. According to the vendor driver,
> these are used for TX power training.
>
> With these changes rtl8xxxu sets the TX power of RTL8192CU the same
> as the vendor driver.
>
> None of this appears to have any effect on my RTL8192CU device.
> ---
> My RTL8192CU with rtl8xxxu has lower upload speed compared to the
> vendor driver, so I compared the register writes and found
> differences in the TX power stuff.
>
> Jes, do you remember why you subtracted 1 from the power index?
> That has to be on purpose. The other differences look unintentional.
> ---
> .../wireless/realtek/rtl8xxxu/rtl8xxxu_core.c | 18 ++++++++----------
> 1 file changed, 8 insertions(+), 10 deletions(-)
>
> diff --git a/drivers/net/wireless/realtek/rtl8xxxu/rtl8xxxu_core.c
> b/drivers/net/wireless/realtek/rtl8xxxu/rtl8xxxu_core.c
> index 5d102a1246a3..e111fb2b2c30 100644
> --- a/drivers/net/wireless/realtek/rtl8xxxu/rtl8xxxu_core.c
> +++ b/drivers/net/wireless/realtek/rtl8xxxu/rtl8xxxu_core.c
> @@ -1510,8 +1510,8 @@ rtl8xxxu_gen1_set_tx_power(struct rtl8xxxu_priv *priv, int channel, bool ht40)
>
> group = rtl8xxxu_gen1_channel_to_group(channel);
>
> - cck[0] = priv->cck_tx_power_index_A[group] - 1;
> - cck[1] = priv->cck_tx_power_index_B[group] - 1;
> + cck[0] = priv->cck_tx_power_index_A[group];
> + cck[1] = priv->cck_tx_power_index_B[group];
>
> if (priv->hi_pa) {
> if (cck[0] > 0x20)
> @@ -1522,10 +1522,6 @@ rtl8xxxu_gen1_set_tx_power(struct rtl8xxxu_priv *priv, int channel, bool ht40)
>
> ofdm[0] = priv->ht40_1s_tx_power_index_A[group];
> ofdm[1] = priv->ht40_1s_tx_power_index_B[group];
> - if (ofdm[0])
> - ofdm[0] -= 1;
> - if (ofdm[1])
> - ofdm[1] -= 1;
>
> ofdmbase[0] = ofdm[0] + priv->ofdm_tx_power_index_diff[group].a;
> ofdmbase[1] = ofdm[1] + priv->ofdm_tx_power_index_diff[group].b;
> @@ -1614,20 +1610,22 @@ rtl8xxxu_gen1_set_tx_power(struct rtl8xxxu_priv *priv, int channel, bool ht40)
>
> rtl8xxxu_write32(priv, REG_TX_AGC_A_MCS15_MCS12,
> mcs_a + power_base->reg_0e1c);
> + val8 = u32_get_bits(mcs_a + power_base->reg_0e1c, 0xff000000);
Comparing to vendor driver, I think the logic here is the same.
> for (i = 0; i < 3; i++) {
> if (i != 2)
> - val8 = (mcsbase[0] > 8) ? (mcsbase[0] - 8) : 0;
> + val8 = (val8 > 8) ? (val8 - 8) : 0;
> else
> - val8 = (mcsbase[0] > 6) ? (mcsbase[0] - 6) : 0;
> + val8 = (val8 > 6) ? (val8 - 6) : 0;
Would you like val8 = min_t(int, val8 - 6, 0); ?
Even, merge two branches into one.
base = i != 2 ? 8 : 6;
val8 = min_t(int, val8 - base, 0);
[...]
