From: "Russell King (Oracle)" <linux@armlinux.org.uk>
To: Maxime Chevallier <maxime.chevallier@bootlin.com>
Cc: davem@davemloft.net, "Andrew Lunn" <andrew@lunn.ch>,
"Jakub Kicinski" <kuba@kernel.org>,
"Eric Dumazet" <edumazet@google.com>,
"Paolo Abeni" <pabeni@redhat.com>,
"Heiner Kallweit" <hkallweit1@gmail.com>,
netdev@vger.kernel.org, linux-kernel@vger.kernel.org,
thomas.petazzoni@bootlin.com,
"Florian Fainelli" <f.fainelli@gmail.com>,
"Köry Maincent" <kory.maincent@bootlin.com>,
"Simon Horman" <horms@kernel.org>,
"Romain Gantois" <romain.gantois@bootlin.com>,
"Antoine Tenart" <atenart@kernel.org>,
"Marek Behún" <kabel@kernel.org>,
"Sean Anderson" <sean.anderson@linux.dev>,
"Bjørn Mork" <bjorn@mork.no>
Subject: Re: [PATCH net-next v2 1/2] net: phy: sfp: Add support for SMBus module access
Date: Tue, 25 Feb 2025 18:04:29 +0000 [thread overview]
Message-ID: <Z74GLblGUPhHID8a@shell.armlinux.org.uk> (raw)
In-Reply-To: <20250225112043.419189-2-maxime.chevallier@bootlin.com>
On Tue, Feb 25, 2025 at 12:20:39PM +0100, Maxime Chevallier wrote:
> The SFP module's eeprom and internals are accessible through an i2c bus.
> However, all the i2c transfers that are performed are SMBus-style
> transfers for read and write operations.
Note that there are SFPs that fail if you access them by byte - the
3FE46541AA locks the bus if you byte access the emulated EEPROM at
0x50, address 0x51. This is documented in sfp_sm_mod_probe().
So there's a very real reason for adding the warning - this module
will not work!
--
RMK's Patch system: https://www.armlinux.org.uk/developer/patches/
FTTP is here! 80Mbps down 10Mbps up. Decent connectivity at last!
next prev parent reply other threads:[~2025-02-25 18:04 UTC|newest]
Thread overview: 13+ messages / expand[flat|nested] mbox.gz Atom feed top
2025-02-25 11:20 [PATCH net-next v2 0/2] net: phy: sfp: Add single-byte SMBus SFP access Maxime Chevallier
2025-02-25 11:20 ` [PATCH net-next v2 1/2] net: phy: sfp: Add support for SMBus module access Maxime Chevallier
2025-02-25 13:41 ` Andrew Lunn
2025-02-25 13:56 ` Maxime Chevallier
2025-02-25 14:58 ` Andrew Lunn
2025-02-25 18:23 ` Russell King (Oracle)
2025-02-25 18:06 ` Russell King (Oracle)
2025-02-25 18:04 ` Russell King (Oracle) [this message]
2025-02-25 18:20 ` Maxime Chevallier
2025-02-25 18:41 ` Sean Anderson
2025-02-25 18:48 ` Maxime Chevallier
2025-03-08 18:42 ` Maxime Chevallier
2025-02-25 11:20 ` [PATCH net-next v2 2/2] net: mdio: mdio-i2c: Add support for single-byte SMBus operations Maxime Chevallier
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=Z74GLblGUPhHID8a@shell.armlinux.org.uk \
--to=linux@armlinux.org.uk \
--cc=andrew@lunn.ch \
--cc=atenart@kernel.org \
--cc=bjorn@mork.no \
--cc=davem@davemloft.net \
--cc=edumazet@google.com \
--cc=f.fainelli@gmail.com \
--cc=hkallweit1@gmail.com \
--cc=horms@kernel.org \
--cc=kabel@kernel.org \
--cc=kory.maincent@bootlin.com \
--cc=kuba@kernel.org \
--cc=linux-kernel@vger.kernel.org \
--cc=maxime.chevallier@bootlin.com \
--cc=netdev@vger.kernel.org \
--cc=pabeni@redhat.com \
--cc=romain.gantois@bootlin.com \
--cc=sean.anderson@linux.dev \
--cc=thomas.petazzoni@bootlin.com \
/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).