Re: [PATCH 1/5] wifi: wilc1000: set preamble size to auto as default in wilc_init_fw_config()

From: Ajay.Kathat
Date: Thu Jan 18 2024 - 11:52:58 EST


On 1/18/24 08:08, Alexis Lothoré wrote:
> EXTERNAL EMAIL: Do not click links or open attachments unless you know the content is safe
>
> Hi Kalle,
>
> On 1/18/24 10:31, Kalle Valo wrote:
>> Alexis Lothoré <alexis.lothore@xxxxxxxxxxx> wrote:
>>
>>> From: Ajay Singh <ajay.kathat@xxxxxxxxxxxxx>
>>>
>>> Changed the default value preamble to WILC_FW_PREAMBLE_AUTO in
>>> wilc_init_fw_config().
>>>
>>> Signed-off-by: Ajay Singh <ajay.kathat@xxxxxxxxxxxxx>
>>> Signed-off-by: Alexis Lothoré <alexis.lothore@xxxxxxxxxxx>
>>
>> The commit message should always answer to the question "Why?". I can add that
>> if you tell me what to add.
>
> Yeah, sorry for the lack of description, I may have forgotten to update this
> one. I suggest to update it with the following message:
>
> "WILC driver currently applies some default configuration whenever the firmware
> is initialized, and sets the default preamble size to short. However, despite
> this passed option, firmware is also able to successfully connect to access
> points only using long preamble, so this setting does not really enforce short
> preambles and is misleading regarding applied configuration.
>
> Update default configuration and make it match the firmware behavior by passing
> the existing WILC_FW_PREAMBLE_AUTO value (2 instead of 0). The updated setting
> does not really alter firmware behavior since it is still capable to connect to
> both short preamble and long preamble access points, but at list the setting now
> expresses for real the corresponding firmware behavior"
>
> To give a bit of context around this one: I do not have access to the firmware
> internals, I just took the patch from Ajay and I merely did some tests around it
> with multiple APs (basically, making a WILC STA connect and ping the AP), and
> ensured with wireshark to get at least one AP be really "locked" with long
> preamble, with WILC managing to connect to it.
>

Here are some more details about this change. It have been implemented
to address the transmission(Tx) blackout issue observed in the 802.11b
mode. The modification has no impact on the other modes, which will
continue to work as they did in the previous implementation. This change
will allow the 802.11b transmission(2, 5.5, 11Mbps) to use long preamble.


Regards,
Ajay