wifi: rtw89: Lower the timeout in rtw89_fw_read_c2h_reg() for USB

[ Upstream commit 671be46afd1f03de9dc6e4679c88e1a7a81cdff6 ]

This read_poll_timeout_atomic() with a delay of 1 µs and a timeout of
1000000 µs can take ~250 seconds in the worst case because sending a
USB control message takes ~250 µs.

Lower the timeout to 4000 for USB in order to reduce the maximum polling
time to ~1 second.

This problem was observed with RTL8851BU while suspending to RAM with
WOWLAN enabled. The computer sat for 4 minutes with a black screen
before suspending.

Signed-off-by: Bitterblue Smith <rtl8821cerfe2@gmail.com>
Signed-off-by: Ping-Ke Shih <pkshih@realtek.com>
Link: https://patch.msgid.link/09313da6-c865-4e91-b758-4cb38a878796@gmail.com
Signed-off-by: Sasha Levin <sashal@kernel.org>

diff --git a/drivers/net/wireless/realtek/rtw89/fw.c b/drivers/net/wireless/realtek/rtw89/fw.c
index 0f022a5192ac622f83c9481a689e49727082e287..977aadfdf997ffa4a02ae6e16b43a6de93e2550a 100644 (file)
--- a/drivers/net/wireless/realtek/rtw89/fw.c
+++ b/drivers/net/wireless/realtek/rtw89/fw.c
@@ -2397,13 +2397,18 @@ static int rtw89_fw_read_c2h_reg(struct rtw89_dev *rtwdev,
 {
        const struct rtw89_chip_info *chip = rtwdev->chip;
        const u32 *c2h_reg = chip->c2h_regs;
-       u32 ret;
+       u32 ret, timeout;
        u8 i, val;
 
        info->id = RTW89_FWCMD_C2HREG_FUNC_NULL;
 
+       if (rtwdev->hci.type == RTW89_HCI_TYPE_USB)
+               timeout = RTW89_C2H_TIMEOUT_USB;
+       else
+               timeout = RTW89_C2H_TIMEOUT;
+
        ret = read_poll_timeout_atomic(rtw89_read8, val, val, 1,
-                                      RTW89_C2H_TIMEOUT, false, rtwdev,
+                                      timeout, false, rtwdev,
                                       chip->c2h_ctrl_reg);
        if (ret) {
                rtw89_warn(rtwdev, "c2h reg timeout\n");

diff --git a/drivers/net/wireless/realtek/rtw89/fw.h b/drivers/net/wireless/realtek/rtw89/fw.h
index 0047d5d0e9b193a90ddd727dc532cdb005799be0..d0f2c5b22513136c2d8185ae6c8f76d75e25eca2 100644 (file)
--- a/drivers/net/wireless/realtek/rtw89/fw.h
+++ b/drivers/net/wireless/realtek/rtw89/fw.h
@@ -33,6 +33,8 @@ enum rtw89_fw_dl_status {
 #define RTW89_C2HREG_HDR_LEN 2
 #define RTW89_H2CREG_HDR_LEN 2
 #define RTW89_C2H_TIMEOUT 1000000
+#define RTW89_C2H_TIMEOUT_USB 4000
+
 struct rtw89_mac_c2h_info {
        u8 id;
        u8 content_len;