Re: [PATCH 2/2] wifi: rtw89: phy: make RF calibration timeouts non-fatal on USB

Louis Kotze
2026-04-15T11:13:58Z

On Tue, 14 Apr 2026 06:39 +0000, Ping-Ke Shih wrote:
> If calibration timeouts, the performance might be bad. How about just
> to enlarge timeout time in 1/2 patch?
> [...]
> It seems like we don't actually handle the return code for now.
> Could you point out the path you encountered?

You're right on both points — dropping this patch in v2.

On the return code: it is indeed discarded by all 8922a callers of
rtw89_phy_rfk_*_and_wait() (11 call sites). My original "connection
failure" report was the host dropping the link after repeated
"failed to wait RF DACK" kernel warnings, not a return-code cascade.
The 4x multiplier in 1/2 already fixes the observable symptom.

Also, on 8922d rtw8922d_rfk_tssi() does check the return and uses
the failure to fall back by clearing is_tssi_mode — making the call
non-fatal on USB would silently break that fallback. Not something
I should ship, even for hardware I don't own.

On enlarging 1/2 only: re-verified the 4x multiplier under stress-ng
(CPU, memory, combined). DACK peaks at 71ms on 5GHz in every
scenario, including baseline idle — the calibrations are I/O bound
on the USB H2C/C2H round-trip, not CPU/memory bound, so host stress
doesn't move the numbers. 4x leaves ~3.3x headroom on the worst case.
Full matrix is in the v2 1/2 commit message.

v2 keeps only 1/2, with the comment-style fix. Sending shortly.

Louis