Ping-Ke Shih <pkshih@xxxxxxxxxxx> writes: >> -----Original Message----- >> From: Martin Blumenstingl <martin.blumenstingl@xxxxxxxxxxxxxx> >> Sent: Monday, May 15, 2023 4:04 AM >> To: linux-wireless@xxxxxxxxxxxxxxx >> Cc: linux-kernel@xxxxxxxxxxxxxxx; Ping-Ke Shih <pkshih@xxxxxxxxxxx>; tony0620emma@xxxxxxxxx; >> kvalo@xxxxxxxxxx; Martin Blumenstingl <martin.blumenstingl@xxxxxxxxxxxxxx>; Larry Finger >> <Larry.Finger@xxxxxxxxxxxx>; Rudi Heitbaum <rudi@xxxxxxxxxxxx> >> Subject: [PATCH wireless v1] wifi: rtw88: sdio: Always use two consecutive bytes for word operations >> >> The Allwinner sunxi-mmc controller cannot handle word (16 bit) >> transfers. So and sdio_{read,write}w fails with messages like the >> following example using an RTL8822BS (but the same problems were also >> observed with RTL8822CS and RTL8723DS chips): >> rtw_8822bs mmc1:0001:1: Firmware version 27.2.0, H2C version 13 >> sunxi-mmc 4021000.mmc: unaligned scatterlist: os f80 length 2 >> sunxi-mmc 4021000.mmc: map DMA failed >> rtw_8822bs mmc1:0001:1: sdio read16 failed (0x10230): -22 >> >> Use two consecutive single byte accesses for word operations instead. It >> turns out that upon closer inspection this is also what the vendor >> driver does, even though it does have support for sdio_{read,write}w. So >> we can conclude that the rtw88 chips do support word access but only on >> SDIO controllers that also support it. Since there's no way to detect if >> the controller supports word access or not the rtw88 sdio driver >> switches to the easiest approach: avoiding word access. >> >> Reported-by: Larry Finger <Larry.Finger@xxxxxxxxxxxx> >> Closes: https://lore.kernel.org/linux-wireless/527585e5-9cdd-66ed-c3af-6da162f4b720@xxxxxxxxxxxx/ > > "Closes:" seems not a regular tag. Use "Link: " instead. Actually the documentation now talks about Closes tag: https://docs.kernel.org/process/5.Posting.html#patch-formatting-and-changelogs I guess this tag is a recent addition? -- https://patchwork.kernel.org/project/linux-wireless/list/ https://wireless.wiki.kernel.org/en/developers/documentation/submittingpatches