rtlwifi: rtl8192c: Add routines to save/restore power index registers

commit 97204e93 upstream.
Signed-off-by: Larry Finger <Larry.Finger@lwfinger.net>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/net/wireless/rtlwifi/rtl8192c/dm_common.c

@@ -158,6 +158,42 @@ static const u8 cckswing_table_ch14[CCK_TABLE_SIZE][8] = {
 	{0x09, 0x08, 0x07, 0x04, 0x00, 0x00, 0x00, 0x00}
 };
 
+static u32 power_index_reg[6] = {0xc90, 0xc91, 0xc92, 0xc98, 0xc99, 0xc9a};
+
+void dm_restorepowerindex(struct ieee80211_hw *hw)
+{
+	struct rtl_priv *rtlpriv = rtl_priv(hw);
+	u8	index;
+
+	for (index = 0; index < 6; index++)
+		rtl_write_byte(rtlpriv, power_index_reg[index],
+			       rtlpriv->dm.powerindex_backup[index]);
+}
+EXPORT_SYMBOL_GPL(dm_restorepowerindex);
+
+void dm_writepowerindex(struct ieee80211_hw *hw, u8 value)
+{
+	struct rtl_priv *rtlpriv = rtl_priv(hw);
+	u8 index;
+
+	for (index = 0; index < 6; index++)
+		rtl_write_byte(rtlpriv, power_index_reg[index], value);
+}
+EXPORT_SYMBOL_GPL(dm_writepowerindex);
+
+void dm_savepowerindex(struct ieee80211_hw *hw)
+{
+	struct rtl_priv *rtlpriv = rtl_priv(hw);
+	u8 index;
+	u8 tmp;
+
+	for (index = 0; index < 6; index++) {
+		tmp = rtl_read_byte(rtlpriv, power_index_reg[index]);
+		rtlpriv->dm.powerindex_backup[index] = tmp;
+	}
+}
+EXPORT_SYMBOL_GPL(dm_savepowerindex);
+
 static void rtl92c_dm_diginit(struct ieee80211_hw *hw)
 {
 	struct rtl_priv *rtlpriv = rtl_priv(hw);