Re: [PATCHv7 1/3] nl80211/cfg80211: add radar detection command/event

[Zefir Kurtisi <zefir.kurtisi@neratec.com>]

On 01/29/2013 01:21 PM, Simon Wunderlich wrote:
> From: Victor Goldenshtein <victorg@ti.com>
> 
> [...]
>  
>  /**
> + * enum ieee80211_dfs_state - DFS states for channels
> + *
> + * Channel states used by the DFS code.
> + *
> + * @IEEE80211_DFS_USABLE: The channel can be used, but channel availability
> + *	check (CAC) must be performed before using it for AP or IBSS.
> + * @IEEE80211_DFS_UNAVAILABLE: A radar has been detected on this channel, it
> + *	is therefore marked as not available.
> + * @IEEE80211_DFS_AVAILABLE: The channel has been CAC checked and is available.
> + */
> +
> +enum ieee80211_dfs_state {
> +	IEEE80211_DFS_USABLE,
> +	IEEE80211_DFS_UNAVAILABLE,
> +	IEEE80211_DFS_AVAILABLE,
> +};
> +
Not sure if IEEE80211_DFS_UNKNOWN is not missing here, i.e. whether a channel that
never passed a CAC (or the CAC has been aborted) is always USABLE. Once I realized
why ETSI defined an UNKNOWN state, but forgot meanwhile - so maybe only relevant
for managed operation (like an UNKNOWN state can be overridden by external
information, whereas e.g. UNAVAILABLE can't).

Furthermore, is there a reason to define an additional wireless_dev.cac_started
flag vs. adding a IEEE80211_DFS_CAC state?