From: Arend van Spriel <arend@broadcom.com>
To: Daniel Drake <drake@endlessm.com>, <brcm80211-dev-list@broadcom.com>
Cc: <linux-wireless@vger.kernel.org>
Subject: Re: brcmfmac: command request size is determined by expected response size?
Date: Mon, 11 Aug 2014 10:53:01 +0200 [thread overview]
Message-ID: <53E8846D.5080003@broadcom.com> (raw)
In-Reply-To: <CAD8Lp47RrOtTKqKQirUwSbfsvqzuStc4TOWc8OXUYBzdjhJ_JA@mail.gmail.com>
On 08/11/2014 10:35 AM, Daniel Drake wrote:
> Hi,
>
> Looking at brcmfmac in Linux 3.16 with a BCM43241 SDIO card, I noticed that
> brcmf_construct_reginfo() constructs and submits a really large
> (1.5kb) request to the card. However, the actual request seems really
> small and trivial (a header, the word "chanspecs" and not much more),
> and we end up sending a whole lot of zeroes to fill the 1.5kb
> allocation (MEDLEN).
>
> I can understand that the card may wish to send 1.5kb in response, but
> does the request itself really need to be the same size?
The main reason is indeed that the request buffer is used by the device
firmware for the response message. That is a design decision in the
firmware that we must adhere to.
Regards,
Arend
prev parent reply other threads:[~2014-08-11 8:53 UTC|newest]
Thread overview: 2+ messages / expand[flat|nested] mbox.gz Atom feed top
2014-08-11 8:35 brcmfmac: command request size is determined by expected response size? Daniel Drake
2014-08-11 8:53 ` Arend van Spriel [this message]
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=53E8846D.5080003@broadcom.com \
--to=arend@broadcom.com \
--cc=brcm80211-dev-list@broadcom.com \
--cc=drake@endlessm.com \
--cc=linux-wireless@vger.kernel.org \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).