[PATCH 6.12 294/567] wifi: rtw88: limit indirect IO under powered off for RTL8822CS

Greg Kroah-Hartman
2026-01-06T17:30:25Z

From: Ping-Ke Shih <pkshih@realtek.com>

[ Upstream commit f3ccdfda345ca9a624ea425840a926b8338c1e25 ]

The indirect IO is necessary for RTL8822CS, but not necessary for other
chips. Otherwiese, it throws errors and becomes unusable.

rtw88_8723cs mmc1:0001:1: WOW Firmware version 11.0.0, H2C version 0
rtw88_8723cs mmc1:0001:1: Firmware version 11.0.0, H2C version 0
rtw88_8723cs mmc1:0001:1: sdio read32 failed (0xf0): -110
rtw88_8723cs mmc1:0001:1: sdio write8 failed (0x1c): -110
rtw88_8723cs mmc1:0001:1: sdio read32 failed (0xf0): -110

By vendor driver, only RTL8822CS and RTL8822ES need indirect IO, but
RTL8822ES isn't supported yet. Therefore, limit it to RTL8822CS only.

Reported-by: Andrey Skvortsov <andrej.skvortzov@gmail.com>
Closes: https://lore.kernel.org/linux-wireless/07a32e2d6c764eb1bd9415b5a921a652@realtek.com/T/#m997b4522f7209ba629561c776bfd1d13ab24c1d4
Fixes: 58de1f91e033 ("wifi: rtw88: sdio: use indirect IO for device registers before power-on")
Signed-off-by: Ping-Ke Shih <pkshih@realtek.com>
Tested-by: Andrey Skvortsov <andrej.skvortzov@gmail.com>
Link: https://patch.msgid.link/1764034729-1251-1-git-send-email-pkshih@realtek.com
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
drivers/net/wireless/realtek/rtw88/sdio.c | 4 +++-
1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/drivers/net/wireless/realtek/rtw88/sdio.c b/drivers/net/wireless/realtek/rtw88/sdio.c
index d6bea5ec8e24..d8db341a5731 100644
--- a/drivers/net/wireless/realtek/rtw88/sdio.c
+++ b/drivers/net/wireless/realtek/rtw88/sdio.c
@@ -144,8 +144,10 @@ static u32 rtw_sdio_to_io_address(struct rtw_dev *rtwdev, u32 addr,

static bool rtw_sdio_use_direct_io(struct rtw_dev *rtwdev, u32 addr)
{
+ bool might_indirect_under_power_off = rtwdev->chip->id == RTW_CHIP_TYPE_8822C;
+
if (!test_bit(RTW_FLAG_POWERON, rtwdev->flags) &&
- !rtw_sdio_is_bus_addr(addr))
+ !rtw_sdio_is_bus_addr(addr) && might_indirect_under_power_off)
return false;

return !rtw_sdio_is_sdio30_supported(rtwdev) ||
--
2.51.0