Re: [PATCH 1/2] cfg80211: Remove unused cfg80211_background_cac_abort

[Vasanthakumar Thiagarajan <quic_vthiagar@quicinc.com>]

On 10/7/2024 4:23 AM, linux@treblig.org wrote:
> From: "Dr. David Alan Gilbert" <linux@treblig.org>
> 
> cfg80211_background_cac_abort() is unused.
> It got renamed from cfg80211_offchan_cac_abort by commit
> a95bfb876fa8 ("cfg80211: rename offchannel_chain structs to background_chain to avoid confusion with ETSI standard")
> 
> and that was originally added in commit
> 1507b1531981 ("cfg80211: move offchan_cac_event to a dedicated work")
> but never used.
> 
> To me it looks like the queue is still used (I see a queue_work
> in __cfg80211_radar_event), so I think it's just the wrapper that's
> unused.
> 
> Remove cfg80211_background_cac_abort.
> 
> Signed-off-by: Dr. David Alan Gilbert <linux@treblig.org>
> ---
>   include/net/cfg80211.h | 9 ---------
>   net/wireless/mlme.c    | 8 --------
>   2 files changed, 17 deletions(-)
> 
> diff --git a/include/net/cfg80211.h b/include/net/cfg80211.h
> index 69ec1eb41a09..fd843a519329 100644
> --- a/include/net/cfg80211.h
> +++ b/include/net/cfg80211.h
> @@ -8752,15 +8752,6 @@ void cfg80211_cac_event(struct net_device *netdev,
>   			enum nl80211_radar_event event, gfp_t gfp,
>   			unsigned int link_id);
>   
> -/**
> - * cfg80211_background_cac_abort - Channel Availability Check offchan abort event
> - * @wiphy: the wiphy
> - *
> - * This function is called by the driver when a Channel Availability Check
> - * (CAC) is aborted by a offchannel dedicated chain.
> - */
> -void cfg80211_background_cac_abort(struct wiphy *wiphy);
> -
>   /**
>    * cfg80211_gtk_rekey_notify - notify userspace about driver rekeying
>    * @dev: network device
> diff --git a/net/wireless/mlme.c b/net/wireless/mlme.c
> index 4dac81854721..8ec236bbbc7c 100644
> --- a/net/wireless/mlme.c
> +++ b/net/wireless/mlme.c
> @@ -1226,14 +1226,6 @@ void cfg80211_background_cac_abort_wk(struct work_struct *work)
>   				      NL80211_RADAR_CAC_ABORTED);
>   }
>   
> -void cfg80211_background_cac_abort(struct wiphy *wiphy)
> -{
> -	struct cfg80211_registered_device *rdev = wiphy_to_rdev(wiphy);
> -
> -	queue_work(cfg80211_wq, &rdev->background_cac_abort_wk);
> -}
> -EXPORT_SYMBOL(cfg80211_background_cac_abort);
> -

We have an internal WIP ath driver implementation for background radar feature
calling this function to notify the background CAC abort state. There is definitely
real use case for this function.

Vasanth