[PATCH v2 1/2] wifi: rtw88: usb: Support USB 3 with RTL8812AU

[Bitterblue Smith <rtl8821cerfe2@xxxxxxxxx>]

Add the function to automatically switch the RTL8812AU into USB 3 mode.

Signed-off-by: Bitterblue Smith <rtl8821cerfe2@xxxxxxxxx>
---
v2:
 - Add functions to check if the chip is "old" or "new".
---
 drivers/net/wireless/realtek/rtw88/usb.c | 44 ++++++++++++++++++++++--
 1 file changed, 42 insertions(+), 2 deletions(-)

diff --git a/drivers/net/wireless/realtek/rtw88/usb.c b/drivers/net/wireless/realtek/rtw88/usb.c
index 6fa3c37205f5..6f64c3fd96ae 100644
--- a/drivers/net/wireless/realtek/rtw88/usb.c
+++ b/drivers/net/wireless/realtek/rtw88/usb.c
@@ -931,6 +931,32 @@ static void rtw_usb_intf_deinit(struct rtw_dev *rtwdev,
 	usb_set_intfdata(intf, NULL);
 }
 
+static int rtw_usb_switch_mode_old(struct rtw_dev *rtwdev)
+{
+	struct rtw_usb *rtwusb = rtw_get_usb_priv(rtwdev);
+	enum usb_device_speed cur_speed = rtwusb->udev->speed;
+	u8 hci_opt;
+
+	if (cur_speed == USB_SPEED_HIGH) {
+		hci_opt = rtw_read8(rtwdev, REG_HCI_OPT_CTRL);
+
+		if ((hci_opt & (BIT(2) | BIT(3))) != BIT(3)) {
+			rtw_write8(rtwdev, REG_HCI_OPT_CTRL, 0x8);
+			rtw_write8(rtwdev, REG_SYS_SDIO_CTRL, 0x2);
+			rtw_write8(rtwdev, REG_ACLK_MON, 0x1);
+			rtw_write8(rtwdev, 0x3d, 0x3);
+			/* usb disconnect */
+			rtw_write8(rtwdev, REG_SYS_PW_CTRL + 1, 0x80);
+			return 1;
+		}
+	} else if (cur_speed == USB_SPEED_SUPER) {
+		rtw_write8_clr(rtwdev, REG_SYS_SDIO_CTRL, BIT(1));
+		rtw_write8_clr(rtwdev, REG_ACLK_MON, BIT(0));
+	}
+
+	return 0;
+}
+
 static int rtw_usb_switch_mode_new(struct rtw_dev *rtwdev)
 {
 	enum usb_device_speed cur_speed;
@@ -980,11 +1006,22 @@ static int rtw_usb_switch_mode_new(struct rtw_dev *rtwdev)
 	return 1;
 }
 
+static bool rtw_usb3_chip_old(u8 chip_id)
+{
+	return chip_id == RTW_CHIP_TYPE_8812A;
+}
+
+static bool rtw_usb3_chip_new(u8 chip_id)
+{
+	return chip_id == RTW_CHIP_TYPE_8822C ||
+	       chip_id == RTW_CHIP_TYPE_8822B;
+}
+
 static int rtw_usb_switch_mode(struct rtw_dev *rtwdev)
 {
 	u8 id = rtwdev->chip->id;
 
-	if (id != RTW_CHIP_TYPE_8822C && id != RTW_CHIP_TYPE_8822B)
+	if (!rtw_usb3_chip_new(id) && !rtw_usb3_chip_old(id))
 		return 0;
 
 	if (!rtwdev->efuse.usb_mode_switch) {
@@ -999,7 +1036,10 @@ static int rtw_usb_switch_mode(struct rtw_dev *rtwdev)
 		return 0;
 	}
 
-	return rtw_usb_switch_mode_new(rtwdev);
+	if (rtw_usb3_chip_old(id))
+		return rtw_usb_switch_mode_old(rtwdev);
+	else
+		return rtw_usb_switch_mode_new(rtwdev);
 }
 
 int rtw_usb_probe(struct usb_interface *intf, const struct usb_device_id *id)
-- 
2.47.0