[+cc: Maximilian and Jonas] Hello Sharvari! I'm forwarding to you this email about initialization issues in mwifiex driver. Could you as a new NXP maintainer of mwifiex driver look at it? On Friday 12 June 2020 12:35:01 Pali Rohár wrote: > Hello! > > I was looking at mwifiex code which initialize card firmware and linux > network interface and I think that there are some issues with this code > path. > > There is a function mwifiex_sta_init_cmd() which basically doing two > different things: > > * initial card firmware initialization > * configuration of interface parameters via card firmware > > That function has following definition: > > int mwifiex_sta_init_cmd(struct mwifiex_private *priv, u8 first_sta, bool init); > > 'first_sta' and 'init' is FALSE when doing just configuration of > interface parameters (by cfg80211 callbacks). > > 'init' is TRUE when doing initial card firmware initialization and it is > called when mwifiex driver is doing setup of card. But this function is > called with 'init' set to TRUE multiple times when card driver was > configured to create multiple linux network interfaces. In this case > 'first_sta' is TRUE only for the first call of this function. > > And now the first suspicious thing is: Why mwifiex driver calls that > initial card firmware initialization multiple times when network > interfaces are created during driver setup, and not when they are > created later by "iw phy phyX interface add ..."? > > Next, looking at code of that function mwifiex_sta_init_cmd() it looks > like that all commands send to firmware are "global" and affects all > existing mwifiex network interfaces. Why then it is needed to call this > function when creating a new interface? (E.g. second bssid for AP mode). > > Also if it really affects all existing interfaces, it means that > creating a new interface changes configured cfg80211 parameters of all > existing interfaces to some default values. > > This also affects power save settings which I described in previous email: > https://lore.kernel.org/linux-wireless/20200609111544.v7u5ort3yk4s7coy@pali/ > > And the last and the most suspicious thing in that mwifiex_sta_init_cmd > function is that some AP related code is executed only during initial > card firmware initialization and only if initial interface is AP mode > ('init' = TRUE, 'first_sta' = TRUE, mode = 'AP'). > > Seems that driver behaves differently if interfaces are created by > standard 'iw phy phyX interface add ..." command (via cfg80211 layer) > and differently if interfaces are created automatically during driver > setup function. > > Are there any reasons for these differences? And what to do with the > fact that most firmware commands which affects all interfaces and not > just one which is initializing? > > These issues which I described makes it hard for me to understand what > is driver really doing and what should be correct behavior. > > By the way, do you have documentation for firmware commands?
