Patch "wifi: rtl8xxxu: 8188f: Limit TX power index" has been added to the 6.6-stable tree

[Sasha Levin <sashal@xxxxxxxxxx>]

This is a note to let you know that I've just added the patch titled

    wifi: rtl8xxxu: 8188f: Limit TX power index

to the 6.6-stable tree which can be found at:
    http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary

The filename of the patch is:
     wifi-rtl8xxxu-8188f-limit-tx-power-index.patch
and it can be found in the queue-6.6 subdirectory.

If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.



commit a3ac43ca8b53d859c31d5b19d5964335ecdea302
Author: Martin Kaistra <martin.kaistra@xxxxxxxxxxxxx>
Date:   Mon Jun 24 16:00:37 2024 +0200

    wifi: rtl8xxxu: 8188f: Limit TX power index
    
    [ Upstream commit d0b4b8ef083ca46d5d318e66a30fb80e0abbb90d ]
    
    TX power index is read from the efuse on init, the values get written to
    the TX power registers when the channel gets switched.
    
    When the chip has not yet been calibrated, the efuse values are 0xFF,
    which on some boards leads to USB timeouts for reading/writing registers
    after the first frames have been sent.
    
    The vendor driver (v5.11.5-1) checks for these invalid values and sets
    default values instead. Implement something similar in
    rtl8188fu_parse_efuse().
    
    Fixes: c888183b21f3 ("wifi: rtl8xxxu: Support new chip RTL8188FU")
    Signed-off-by: Martin Kaistra <martin.kaistra@xxxxxxxxxxxxx>
    Reviewed-by: Ping-Ke Shih <pkshih@xxxxxxxxxxx>
    Signed-off-by: Ping-Ke Shih <pkshih@xxxxxxxxxxx>
    Link: https://patch.msgid.link/20240624140037.231657-1-martin.kaistra@xxxxxxxxxxxxx
    Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>

diff --git a/drivers/net/wireless/realtek/rtl8xxxu/rtl8xxxu_8188f.c b/drivers/net/wireless/realtek/rtl8xxxu/rtl8xxxu_8188f.c
index 1e1c8fa194cb8..0466b8be5df01 100644
--- a/drivers/net/wireless/realtek/rtl8xxxu/rtl8xxxu_8188f.c
+++ b/drivers/net/wireless/realtek/rtl8xxxu/rtl8xxxu_8188f.c
@@ -713,9 +713,14 @@ static void rtl8188fu_init_statistics(struct rtl8xxxu_priv *priv)
 	rtl8xxxu_write32(priv, REG_OFDM0_FA_RSTC, val32);
 }
 
+#define TX_POWER_INDEX_MAX 0x3F
+#define TX_POWER_INDEX_DEFAULT_CCK 0x22
+#define TX_POWER_INDEX_DEFAULT_HT40 0x27
+
 static int rtl8188fu_parse_efuse(struct rtl8xxxu_priv *priv)
 {
 	struct rtl8188fu_efuse *efuse = &priv->efuse_wifi.efuse8188fu;
+	int i;
 
 	if (efuse->rtl_id != cpu_to_le16(0x8129))
 		return -EINVAL;
@@ -729,6 +734,16 @@ static int rtl8188fu_parse_efuse(struct rtl8xxxu_priv *priv)
 	       efuse->tx_power_index_A.ht40_base,
 	       sizeof(efuse->tx_power_index_A.ht40_base));
 
+	for (i = 0; i < ARRAY_SIZE(priv->cck_tx_power_index_A); i++) {
+		if (priv->cck_tx_power_index_A[i] > TX_POWER_INDEX_MAX)
+			priv->cck_tx_power_index_A[i] = TX_POWER_INDEX_DEFAULT_CCK;
+	}
+
+	for (i = 0; i < ARRAY_SIZE(priv->ht40_1s_tx_power_index_A); i++) {
+		if (priv->ht40_1s_tx_power_index_A[i] > TX_POWER_INDEX_MAX)
+			priv->ht40_1s_tx_power_index_A[i] = TX_POWER_INDEX_DEFAULT_HT40;
+	}
+
 	priv->ofdm_tx_power_diff[0].a = efuse->tx_power_index_A.ht20_ofdm_1s_diff.a;
 	priv->ht20_tx_power_diff[0].a = efuse->tx_power_index_A.ht20_ofdm_1s_diff.b;