Re: [PATCH] AP: Allow downgrading to 20MHz based on OBSS results

Hi,
Please drop following patch as it is causing a regression.
I will send the next version.
Thanks.

On 2020-01-08 16:53, Aloka Dixit wrote:
> Before operating on 40MHz in 2.4GHz, AP looks for overlapping
> BSS in neighboring channels. Upon OBSS detection, AP should
> downgrade to 20MHz bandwidth. This decistion is broken now
> for HE40. As of now ieee80211n_check_scan skips the rollback
> step for 20MHz as allowed_ht40_channel_pair returns true
> when primary and secondary channels are same. Fix that.
> 
> Signed-off-by: Aloka Dixit <[email protected]>
> ---
>  src/common/hw_features_common.c | 7 ++++++-
>  1 file changed, 6 insertions(+), 1 deletion(-)
> 
> diff --git a/src/common/hw_features_common.c 
> b/src/common/hw_features_common.c
> index 19593a521f9e..d691cc939b2b 100644
> --- a/src/common/hw_features_common.c
> +++ b/src/common/hw_features_common.c
> @@ -111,7 +111,12 @@ int allowed_ht40_channel_pair(enum hostapd_hw_mode 
> mode,
> 
>  	ht40_plus = pri_chan < sec_chan;
> 
> -	if (pri_chan == sec_chan || !sec_chan) {
> +	/* If primary and secondary channels are set to same value,
> +	 * operating width should be changed to 20MHz. */
> +	if (pri_chan == sec_chan)
> +		return 0;
> +
> +	if(!sec_chan) {
>  		if (chan_pri_allowed(p_chan))
>  			return 1; /* HT40 not used */