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From:   JH <jupiter.hce@gmail.com>
Date:   Thu, 6 Feb 2020 22:08:16 +1100
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Subject: Re: Failed to can wifi Invalid Sched_scan parameters
To:     Daniel Wagner <wagi@monom.org>
Cc:     linux-wireless <linux-wireless@vger.kernel.org>,
        connman <connman@lists.01.org>
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Hi Daniel,

On 2/4/20, Daniel Wagner <wagi@monom.org> wrote:
> The 'Invalid Sched_scan parameters' indicates, wpa_supplicant is
> providing the wrong parameters. Best thing is to monitor between
> wpa_supplicant and kernel the netlink messages. iwmon is an excellent
> tool for this.

Thanks for the tip, I did not realize that connman is actually heavily
relied on wpa_supplicant, if I restarted wpa_supplicant, most of time
it popped up mwifiex_sdio messages, then the WiFi could be up:

$ systemctl restart wpa_supplicant
[  371.617417] mwifiex_sdio mmc0:0001:1: info: 2
[  371.647545] mwifiex_sdio mmc0:0001:1: info: associated to bssid 34:08:04:12:y
[  371.726667] IPv6: ADDRCONF(NETDEV_CHANGE): mlan0: link becomes ready
[  371.772758] mwifiex_sdio mmc0:0001:1: CMD_RESP: cmd 0x23f error, result=0x2

But sometime when I restated wpa_supplicant, that message did not
come, the WiFi network was still down.

How is mwifiex_sdio related to wpa_supplicant?

Why it is nondeterministic, sometime restart wpa_supplicant could
bring mwifiex_sdio and WiFi up, something it couldn't?

I think mwifiex_sdio is the lowest layer to interact to WiFi modem, in
which circumstance it could bring WiFi modem up and in which
circumstance it couldn't?

That is far too unstable, I always thought I could rely on connman for
WiFi connection stability, but it seems that beyond connman capacity,
so what I can do when the WiFi is not up when restart wpa_supplicant
could not fix it?

Thank you very much Daniel.

Kind regards,

- jh