[PATCH] wifi: rtl8xxxu: fix LED control code of RTL8192FU

[Zenm Chen <zenmchen@gmail.com>]

ASUS USB-N13 C1 is a wifi adapter based on a RTL8192FU chip and its LED
doesn't blink with the rtl8xxxu driver. This patch fix this via writing
the correct value to the register "REG_LEDCFG0".

This was tested with these two wifi adapters:
ASUS USB-N13 C1	(vid=0x0b05, pid=0x18f1, rfe_type=0x1)
MERCURY MW310UH	(vid=0x0bda, pid=0xf192, rfe_type=0x5)

Signed-off-by: Zenm Chen <zenmchen@gmail.com>
---
 .../realtek/rtl8xxxu/rtl8xxxu_8192f.c         | 24 ++++++++-----------
 1 file changed, 10 insertions(+), 14 deletions(-)

diff --git a/drivers/net/wireless/realtek/rtl8xxxu/rtl8xxxu_8192f.c b/drivers/net/wireless/realtek/rtl8xxxu/rtl8xxxu_8192f.c
index 28e93835e05a..ab6d4e4e228e 100644
--- a/drivers/net/wireless/realtek/rtl8xxxu/rtl8xxxu_8192f.c
+++ b/drivers/net/wireless/realtek/rtl8xxxu/rtl8xxxu_8192f.c
@@ -2014,26 +2014,22 @@ static int rtl8192fu_led_brightness_set(struct led_classdev *led_cdev,
 	struct rtl8xxxu_priv *priv = container_of(led_cdev,
 						  struct rtl8xxxu_priv,
 						  led_cdev);
-	u16 ledcfg;
+	u32 ledcfg;
 
 	/* Values obtained by observing the USB traffic from the Windows driver. */
 	rtl8xxxu_write32(priv, REG_SW_GPIO_SHARE_CTRL_0, 0x20080);
 	rtl8xxxu_write32(priv, REG_SW_GPIO_SHARE_CTRL_1, 0x1b0000);
 
-	ledcfg = rtl8xxxu_read16(priv, REG_LEDCFG0);
-
-	if (brightness == LED_OFF) {
-		/* Value obtained like above. */
-		ledcfg = BIT(1) | BIT(7);
-	} else if (brightness == LED_ON) {
-		/* Value obtained like above. */
-		ledcfg = BIT(1) | BIT(7) | BIT(11);
-	} else if (brightness == RTL8XXXU_HW_LED_CONTROL) {
-		/* Value obtained by brute force. */
-		ledcfg = BIT(8) | BIT(9);
-	}
+	/* Enable LED0 GPIO and turn LED0/LED1 off. */
+	ledcfg = (rtl8xxxu_read32(priv, REG_LEDCFG0) | BIT(21)) & ~0xffff;
+
+	/* Values obtained by brute force. */
+	if (brightness == LED_ON)
+		ledcfg |= BIT(3) | BIT(11);
+	else if (brightness == RTL8XXXU_HW_LED_CONTROL)
+		ledcfg |= BIT(0) | BIT(1) | BIT(8) | BIT(9);
 
-	rtl8xxxu_write16(priv, REG_LEDCFG0, ledcfg);
+	rtl8xxxu_write32(priv, REG_LEDCFG0, ledcfg);
 
 	return 0;
 }
-- 
2.42.0