wifi: rtl8xxxu: Add LED control code for RTL8723AU

By default the LED will blink when there is some activity.

This is only compile tested.
Signed-off-by: Bitterblue Smith <rtl8821cerfe2@gmail.com>
Reviewed-by: Ping-Ke Shih <pkshih@realtek.com>
Signed-off-by: Kalle Valo <kvalo@kernel.org>
Link: https://lore.kernel.org/r/73323811-aa58-a1be-7867-a5d45b7ae3d6@gmail.com

drivers/net/wireless/realtek/rtl8xxxu/rtl8xxxu_8723a.c

@@ -457,6 +457,30 @@ s8 rtl8723a_cck_rssi(struct rtl8xxxu_priv *priv, u8 cck_agc_rpt)
 	return rx_pwr_all;
 }
 
+static int rtl8723au_led_brightness_set(struct led_classdev *led_cdev,
+					enum led_brightness brightness)
+{
+	struct rtl8xxxu_priv *priv = container_of(led_cdev,
+						  struct rtl8xxxu_priv,
+						  led_cdev);
+	u8 ledcfg = rtl8xxxu_read8(priv, REG_LEDCFG2);
+
+	if (brightness == LED_OFF) {
+		ledcfg &= ~LEDCFG2_HW_LED_CONTROL;
+		ledcfg |= LEDCFG2_SW_LED_CONTROL | LEDCFG2_SW_LED_DISABLE;
+	} else if (brightness == LED_ON) {
+		ledcfg &= ~(LEDCFG2_HW_LED_CONTROL | LEDCFG2_SW_LED_DISABLE);
+		ledcfg |= LEDCFG2_SW_LED_CONTROL;
+	} else if (brightness == RTL8XXXU_HW_LED_CONTROL) {
+		ledcfg &= ~LEDCFG2_SW_LED_DISABLE;
+		ledcfg |= LEDCFG2_HW_LED_CONTROL | LEDCFG2_HW_LED_ENABLE;
+	}
+
+	rtl8xxxu_write8(priv, REG_LEDCFG2, ledcfg);
+
+	return 0;
+}
+
 struct rtl8xxxu_fileops rtl8723au_fops = {
 	.identify_chip = rtl8723au_identify_chip,
 	.parse_efuse = rtl8723au_parse_efuse,
@@ -482,6 +506,7 @@ struct rtl8xxxu_fileops rtl8723au_fops = {
 	.fill_txdesc = rtl8xxxu_fill_txdesc_v1,
 	.set_crystal_cap = rtl8723a_set_crystal_cap,
 	.cck_rssi = rtl8723a_cck_rssi,
+	.led_classdev_brightness_set = rtl8723au_led_brightness_set,
 	.writeN_block_size = 1024,
 	.rx_agg_buf_size = 16000,
 	.tx_desc_size = sizeof(struct rtl8xxxu_txdesc32),