[PATCH] hostapd: Add he_ldpc configuration

[MeiChia Chiu (邱美嘉)]

On Mon, 2023-02-20 at 18:54 +0200, Jouni Malinen wrote:
> On Thu, Feb 09, 2023 at 09:59:46AM +0800, MeiChia Chiu wrote:
> > Add configuration option 'he_ldpc' to enable or disable he ldpc
> > support.
> > diff --git a/hostapd/hostapd.conf b/hostapd/hostapd.conf
> > +#he_ldpc: HE LDPC support
> > +# 0 = not supported
> > +# 1 = supported (default)
> > +#he_ldpc=1
> > diff --git a/src/ap/ieee802_11_he.c b/src/ap/ieee802_11_he.c
> > +	if (hapd->iface->conf->he_phy_capab.he_ldpc)
> > +		cap-
> > >he_phy_capab_info[HE_PHYCAP_LDPC_CODING_IN_PAYLOAD_IDX] |=
> > +			HE_PHYCAP_LDPC_CODING_IN_PAYLOAD;
> 
> This would change the default behavior to start advertising LDPC
> support
> in the HE Capabilities element. Is that really the correct thing to
> do
> in all cases? Could there be drivers that do not support this and
> this
> might result in interoperability issues if enabled without an
> explicit
> check for driver capabilities first?
> 

Thanks for your review and feedback. As you mentioned, current
implementation of ieee80211ax_supported_he_capab does not check
hardware capability and just return 1. This should indeed be modified
and I will find time to do that. As to my patch, it would not affect
any flow since I just make HE LDPC configurable which is hard-coded to 
be enabled in the current design. The current hard-coded behavior is
giving us problems and that's why I want to change it to be
configurable. If you agree, I would like to have this HE LDPC
configurability patch to be reviewed and merged first. Later on, I will
send another patch for the HE hardware capability check.