Hi Rob, Bjorn, Kalle, On Thu, 29 Oct 2020 at 19:10, Bjorn Andersson <bjorn.andersson@xxxxxxxxxx> wrote: > > On Tue 29 Sep 14:08 CDT 2020, Rob Herring wrote: > > > On Fri, Sep 25, 2020 at 11:59:41PM +0530, Amit Pundir wrote: > > > There are firmware versions which do not support host capability > > > QMI request. We suspect either the host cap is not implemented or > > > there may be firmware specific issues, but apparently there seem > > > to be a generation of firmware that has this particular behavior. > > > > > > For example, firmware build on Xiaomi Poco F1 (sdm845) phone: > > > "QC_IMAGE_VERSION_STRING=WLAN.HL.2.0.c3-00257-QCAHLSWMTPLZ-1" > > > > > > If we do not skip the host cap QMI request on Poco F1, then we > > > get a QMI_ERR_MALFORMED_MSG_V01 error message in the > > > ath10k_qmi_host_cap_send_sync(). But this error message is not > > > fatal to the firmware nor to the ath10k driver and we can still > > > bring up the WiFi services successfully if we just ignore it. > > > > > > Hence introducing this DeviceTree quirk to skip host capability > > > QMI request for the firmware versions which do not support this > > > feature. > > > > So if you change the WiFi firmware, you may force a DT change too. Those > > are pretty independent things otherwise. > > > > Yes and that's not good. But I looked at somehow derive this from > firmware version numbers etc and it's not working out, so I'm out of > ideas for alternatives. > > > Why can't you just always ignore this error? If you can't deal with this > > entirely in the driver, then it should be part of the WiFi firmware so > > it's always in sync. > > > > Unfortunately the firmware versions I've hit this problem on has gone > belly up when receiving this request, that's why I asked Amit to add a > flag to skip it. So what is next for this DT quirk? I'm OK to go back to my previous of_machine_is_compatible() device specific hack, for now, https://patchwork.kernel.org/project/linux-wireless/patch/1600328501-8832-1-git-send-email-amit.pundir@xxxxxxxxxx/ till we have a reasonable fix in place or receive a vendor firmware drop which fixes this problem (which I believe is highly unlikely though, for this 2+ years old device). Regards, Amit Pundir > > That said, in the devices I've hit this I've managed to get newer > firmware working, which doesn't have either problem. > > Regards, > Bjorn
