Re: [RFC v3 4/8] wifi: mac80211: add support for DFS with multiple radios

[Felix Fietkau <nbd@nbd.name>]

On 07.06.24 06:25, Karthikeyan Periyasamy wrote:
> 
> 
> On 6/6/2024 11:37 PM, Felix Fietkau wrote:
>> DFS can be supported with multi-channel combinations, as long as each DFS
>> capable radio only supports one channel.
>> 
>> Signed-off-by: Felix Fietkau <nbd@nbd.name>
>> ---
>>   net/mac80211/main.c | 32 ++++++++++++++++++++++++--------
>>   1 file changed, 24 insertions(+), 8 deletions(-)
>> 
>> diff --git a/net/mac80211/main.c b/net/mac80211/main.c
>> index 40fbf397ce74..e9c4cf611e94 100644
>> --- a/net/mac80211/main.c
>> +++ b/net/mac80211/main.c
> 
> ...
> 
>>   int ieee80211_register_hw(struct ieee80211_hw *hw)
>>   {
>>   	struct ieee80211_local *local = hw_to_local(hw);
>> @@ -1173,17 +1188,18 @@ int ieee80211_register_hw(struct ieee80211_hw *hw)
>>   			if (comb->num_different_channels > 1)
>>   				return -EINVAL;
>>   		}
>> -	} else {
>> -		/* DFS is not supported with multi-channel combinations yet */
>> -		for (i = 0; i < local->hw.wiphy->n_iface_combinations; i++) {
>> -			const struct ieee80211_iface_combination *comb;
>> -
>> -			comb = &local->hw.wiphy->iface_combinations[i];
>> +	} else if (hw->wiphy->n_radio) {
>> +		for (i = 0; i < hw->wiphy->n_radio; i++) {
>> +			const struct wiphy_radio *radio = &hw->wiphy->radio[i];
>>   
>> -			if (comb->radar_detect_widths &&
>> -			    comb->num_different_channels > 1)
>> +			if (!ieee80211_ifcomb_check_radar(radio->iface_combinations,
>> +							  radio->n_iface_combinations))
>>   				return -EINVAL;
>>   		}
>> +	} else {
>> +		if (!ieee80211_ifcomb_check_radar(hw->wiphy->iface_combinations,
>> +						  hw->wiphy->n_iface_combinations))
>> +			return -EINVAL;
>>   	}
>>   
>>   	/* Only HW csum features are currently compatible with mac80211 */
> 
> Are we omitting the "wiphy->iface_combinations" if the radio specific
> iface combination advertised ?
> 
> If so, it looks like unused "wiphy->iface_combinations" for radio
> specific combination advertised.

This patch series assumes that you have both wiphy->iface_combinations 
and radio->iface_combinations set. wiphy->iface_combinations applies to 
the full wiphy, whereas radio->iface_combinations only applies to vifs 
assigned to the radio.

- Felix