From: Alan Stern <stern@rowland.harvard.edu>
To: Charles.Hyde@dellteam.com
Cc: bjorn@mork.no, <oliver@neukum.org>, <rjw@rjwysocki.net>,
<lenb@kernel.org>, <Mario.Limonciello@dell.com>,
<chip.programmer@gmail.com>, <nic_swsd@realtek.com>,
<linux-usb@vger.kernel.org>, <linux-acpi@vger.kernel.org>
Subject: RE: [PATCH 1/3] net: cdc_ncm: add get/set ethernet address functions
Date: Fri, 6 Sep 2019 14:15:10 -0400 (EDT) [thread overview]
Message-ID: <Pine.LNX.4.44L0.1909061412350.1627-100000@iolanthe.rowland.org> (raw)
In-Reply-To: <43fa8b0a974d426faccf5e6d486af18a@AUSX13MPS307.AMER.DELL.COM>
On Fri, 6 Sep 2019 Charles.Hyde@dellteam.com wrote:
> <snipped>
> > > + ret = usbnet_read_cmd(dev, USB_CDC_GET_NET_ADDRESS,
> > > + USB_DIR_IN | USB_TYPE_CLASS
> > > + | USB_RECIP_INTERFACE, 0,
> > > + USB_REQ_SET_ADDRESS, buf, ETH_ALEN);
> >
> > Where did that USB_REQ_SET_ADDRESS come from? Did you just look up an
> > arbutrary macro that happened to match your device config? How do you
> > expect this to work with a generic NCM device? Or even your own device,
> > when the next firmware revision moves the function to a different interface?
> <snipped>
>
> https://wiki.osdev.org/Universal_Serial_Bus#SET_ADDRESS
>
> https://www.usb.org/document-library/network-control-model-devices-specification-v10-and-errata-and-adopters-agreement
> Download and view the NCM specification v1.0 (Errata 1), dated November 24, 2010. See table 6.2 on page 30. Also see sections 6.2.2 and 6.2.3 on page 32.
>
> USB_REQ_SET_ADDRESS came from include/uapi/linux/usb/ch9.h. This matches the SET_ADDRESS definition from the osdev wiki page, so I used it because the name and numeric values both matched. It further matches what the Windows driver issues.
The names and values may match, but the meanings do not.
USB_REQ_SET_ADDRESS refers to a USB bus address, not a MAC address.
Alan Stern
next prev parent reply other threads:[~2019-09-06 18:15 UTC|newest]
Thread overview: 12+ messages / expand[flat|nested] mbox.gz Atom feed top
2019-09-05 21:01 [PATCH 1/3] net: cdc_ncm: add get/set ethernet address functions Charles.Hyde
2019-09-06 9:02 ` Bjørn Mork
2019-09-06 18:00 ` Charles.Hyde
2019-09-06 18:15 ` Alan Stern [this message]
2019-09-06 18:19 ` Charles.Hyde
2019-09-06 20:07 ` Bjørn Mork
2019-09-06 20:20 ` Charles.Hyde
2019-09-06 20:39 ` Bjørn Mork
2019-09-06 21:00 ` Charles.Hyde
-- strict thread matches above, loose matches on Subject: below --
2019-08-30 19:37 Charles.Hyde
2019-09-02 9:43 ` Oliver Neukum
2019-09-03 16:45 ` Charles.Hyde
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=Pine.LNX.4.44L0.1909061412350.1627-100000@iolanthe.rowland.org \
--to=stern@rowland.harvard.edu \
--cc=Charles.Hyde@dellteam.com \
--cc=Mario.Limonciello@dell.com \
--cc=bjorn@mork.no \
--cc=chip.programmer@gmail.com \
--cc=lenb@kernel.org \
--cc=linux-acpi@vger.kernel.org \
--cc=linux-usb@vger.kernel.org \
--cc=nic_swsd@realtek.com \
--cc=oliver@neukum.org \
--cc=rjw@rjwysocki.net \
/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).