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Date:   Fri, 18 Feb 2022 13:22:27 +0300
From:   Dan Carpenter <dan.carpenter@oracle.com>
To:     Martin Kaiser <martin@kaiser.cx>
Cc:     Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
        Larry Finger <Larry.Finger@lwfinger.net>,
        Phillip Potter <phil@philpotter.co.uk>,
        Michael Straube <straube.linux@gmail.com>,
        linux-staging@lists.linux.dev, linux-kernel@vger.kernel.org
Subject: Re: [PATCH RFC] staging: r8188eu: comment about the chip's packet
 format
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On Fri, Feb 18, 2022 at 10:22:53AM +0100, Martin Kaiser wrote:
> The structs phy_rx_agc_info and phy_status_rpt define parts of the
> header data that the r8188eu chipset sends to this driver via usb.
> 
> Add a comment to clarify that we cannot modify the content of these
> structures and remove seemingly unused fields.
> 
> Signed-off-by: Martin Kaiser <martin@kaiser.cx>
> ---
> 
> Dear all,
> 
> I experimented with "cleaning up" these structures and related code before
> discovering that their content comes from usb packets we receive from the
> r8188eu chipset.
> 
> Would it make sense to add a word of warning to prevent others from
> repeating this exercise?

Just the fact that these structs are endian means they're from the
firmware or the network.

If a struct has a pointer in it, then it's rarely part of the UAPI but
if it has endian data then it probably is.

regards,
dan carpenter