Re: [PATCH V13 8/9] wifi: ath12k: add support for 160 MHz bandwidth

["Nicolas Escande" <nico.escande@gmail.com>]

On Wed May 28, 2025 at 8:16 PM CEST, Pradeep Kumar Chitrapu wrote:
>
>
> On 5/22/2025 1:34 AM, Nicolas Escande wrote:
>> On Wed May 21, 2025 at 11:38 PM CEST, Pradeep Kumar Chitrapu wrote:
>> [...]
>>> Thanks Nicolas,
>>>
>>> I believe IEEE80211_VHT_CAP_SUPP_CHAN_WIDTH_160_80PLUS80MHZ mean only
>>> 80PLUS80 not both 160 and 80PLUS80 and STA must set
>>> IEEE80211_VHT_CAP_SUPP_CHAN_WIDTH_160MHZ flags for indicating 160 MHz
>>> support. Please correct me if my understanding is correct. However I
>>> agree that we must allow STA to connect irrespective of which flag STA
>>> sets as long as bandwidth is 160MHz. I see ath10k and ath11k also allows
>>> this by setting default phymode of MODE_11AC_VHT160 for BW
>>> ==IEEE80211_STA_RX_BW_160 case.
>>> I will make this change in next revision.
>>> Thanks
>>> Pradeep
>> 
>> Hello Pradeep,
>> 
>> Well this is quite unclear for me maybe Johannes or someone more aware of the
>> evolutions of the standard could shime in.
>> 
>>  From what I've gathered:
>>    - the naming IEEE80211_VHT_CAP_SUPP_CHAN_WIDTH_160_80PLUS80MHZ implies both
>>      which points it was the case when added
>>    - and the original 802.11ac-2013 Table 8-183v states:
>> 	Set to 0 if the STA does not support either 160 or 80+80 MHz.
>> 	Set to 1 if the STA supports 160 MHz.
>> 	Set to 2 if the STA supports 160 MHz and 80+80 MHz.
>> 	The value 3 is reserved.
>> 
>> Things get complicated after:
>>   - later versions like 802.11-2020 have deprecated value 2 in favor of the new
>>     Extendeed NSS BW feature
>>   - Table 9-272 still implies both 160 & 80+80
>>   - Table 11-23 & Table 11-24 implies only 80+80 but both talk about the
>>     'VHT Operation' Channel Width field and not the 'VHT Capabilities' Supported
>>     Channel Width. And thoses had different values even in the first AC amendment
>> 
>> So it feels like when no Extended NSS BW Support is used (first gen AC devices),
>> IEEE80211_VHT_CAP_SUPP_CHAN_WIDTH_160_80PLUS80MHZ really means both 160 & 80+80
> Thanks Nicolas for detailed response.
> Request you to kindly review V14 series and let me know if it works?
>
> Thanks
> Pradeep

Hello Pradeep,

Yes your new version fixes the problem for me.

Thanks