[PATCH 2/2] wifi: rtw88: 8703b: stop the PCIe DMA write reaching SDIO

[Cristian Deluxe]

The first entry of trans_act_to_lps_8703b writes 0xff to MAC register
0x301 on every interface. That register is the PCIe DMA control, and
both trans_act_to_lps_8723d and Realtek's own 8703b sequence header
restrict the same entry to PCI, where it is commented "PCIe DMA stop".

So on an RTL8723CS, which is SDIO only, every transition into low power
poked a PCIe register for no reason. Restrict it the way the sibling
chip and the vendor both do.

Tested on an RTL8723CS over SDIO: the interface goes down and back up,
reassociates and takes an address, and a warm reboot brings Wi-Fi back
with no change in behaviour.

Signed-off-by: Cristian Deluxe <me@xxxxxxxxxxxxxxxxxx>
---
 drivers/net/wireless/realtek/rtw88/rtw8703b.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/net/wireless/realtek/rtw88/rtw8703b.c b/drivers/net/wireless/realtek/rtw88/rtw8703b.c
--- a/drivers/net/wireless/realtek/rtw88/rtw8703b.c
+++ b/drivers/net/wireless/realtek/rtw88/rtw8703b.c
@@ -412,7 +412,7 @@ static const struct rtw_pwr_seq_cmd trans_act_to_reset_mcu_8703b[] = {
 static const struct rtw_pwr_seq_cmd trans_act_to_lps_8703b[] = {
 	{0x0301,
 	 RTW_PWR_CUT_ALL_MSK,
-	 RTW_PWR_INTF_ALL_MSK,
+	 RTW_PWR_INTF_PCI_MSK,
 	 RTW_PWR_ADDR_MAC,
 	 RTW_PWR_CMD_WRITE, 0xff, 0xff},
 	{0x0522,
-- 
2.51.0