Sascha Hauer [off-list ref] writes:

The mwifiex chips support simultaneous Accesspoint and station mode,
but this only works when all are using the same channel. The downstream
driver uses ECSA which makes the Accesspoint automatically switch to the
channel the station is going to use.  Until this is implemented in the
mwifiex driver at least catch this situation and bail out with an error.
Userspace doesn't have a meaningful way to figure out what went wrong,
so print an error message to give the user a clue.

Without this patch the driver would timeout on the
HostCmd_CMD_802_11_ASSOCIATE command when creating a station with a
channel different from the one that an existing accesspoint uses.

Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>
Cc: stable@vger.kernel.org

Does this mean that iface combination definitions are wrong? For example:

static const struct
ieee80211_iface_combination mwifiex_iface_comb_ap_sta_drcs = {
	.limits = mwifiex_ap_sta_limits,
	.num_different_channels = 2,
	.n_limits = ARRAY_SIZE(mwifiex_ap_sta_limits),
	.max_interfaces = MWIFIEX_MAX_BSS_NUM,
	.beacon_int_infra_match = true,
};

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