RE: [PATCH rtw-next] wifi: rtw88: sdio: use indirect IO for device registers before power-on

[Ping-Ke Shih <pkshih@realtek.com>]

Andrey Skvortsov <andrej.skvortzov@gmail.com> wrote:
> Hi,
> 
> This patch was recently backported to stable kernels (v6.12.58) and it broke
> wlan on PinePhone, that uses 8723cs SDIO chip. The same problem
> appears of course on latest 6.18-rc6. Reverting this change resolves
> the problem.
> 
> ```
> $ sudo dmesg | grep -i rtw88
> [   24.940551] rtw88_8723cs mmc1:0001:1: WOW Firmware version 11.0.0, H2C version 0
> [   24.953085] rtw88_8723cs mmc1:0001:1: Firmware version 11.0.0, H2C version 0
> [   24.955892] rtw88_8723cs mmc1:0001:1: sdio read32 failed (0xf0): -110
> [   24.973135] rtw88_8723cs mmc1:0001:1: sdio write8 failed (0x1c): -110
> [   24.980673] rtw88_8723cs mmc1:0001:1: sdio read32 failed (0xf0): -110
> ...
> [   25.446691] rtw88_8723cs mmc1:0001:1: sdio read8 failed (0x100): -110
> [   25.453569] rtw88_8723cs mmc1:0001:1: mac power on failed
> [   25.459077] rtw88_8723cs mmc1:0001:1: failed to power on mac
> [   25.464841] rtw88_8723cs mmc1:0001:1: failed to setup chip efuse info
> [   25.464856] rtw88_8723cs mmc1:0001:1: failed to setup chip information
> [   25.478341] rtw88_8723cs mmc1:0001:1: probe with driver rtw88_8723cs failed with error -114
> ```
> 

Check original link of this patch [1] that 8822cs read incorrect from 0xf0
resulting in "rtw88_8822cs mmc1:0001:1: unsupported rf path (1)".

I wonder if we can add additional checking rule of chip ID, like:

--- 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_8703B;
+
        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) ||

[1] https://lore.kernel.org/linux-wireless/699C22B4-A3E3-4206-97D0-22AB3348EBF6@gmail.com/T/#t