linux-kernel - Re: [PATCH v2 0/7] net: phy: adin1100: Add initial support for ADIN1100 industrial PHY

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Date:   Fri, 23 Jul 2021 19:32:57 +0200
From:   Oleksij Rempel <o.rempel@...gutronix.de>
To:     "Russell King (Oracle)" <linux@...linux.org.uk>
Cc:     alexandru.tachici@...log.com, netdev@...r.kernel.org,
        linux-kernel@...r.kernel.org, devicetree@...r.kernel.org,
        robh+dt@...nel.org, andrew@...n.ch, hkallweit1@...il.com,
        davem@...emloft.net, kuba@...nel.org
Subject: Re: [PATCH v2 0/7] net: phy: adin1100: Add initial support for
 ADIN1100 industrial PHY

On Mon, Jul 12, 2021 at 02:33:58PM +0100, Russell King (Oracle) wrote:
> On Mon, Jul 12, 2021 at 04:06:24PM +0300, alexandru.tachici@...log.com wrote:
> > From: Alexandru Tachici <alexandru.tachici@...log.com>
> > 
> > The ADIN1100 is a low power single port 10BASE-T1L transceiver designed for
> > industrial Ethernet applications and is compliant with the IEEE 802.3cg
> > Ethernet standard for long reach 10 Mb/s Single Pair Ethernet.
> > 
> > Ethtool output:
> >         Settings for eth1:
> >         Supported ports: [ TP	 MII ]
> >         Supported link modes:   10baseT1L/Full
> >                                 2400mv
> >                                 1000mv
> 
> The SI unit of voltage is V not v, so milli-volts is mV not mv. Surely,
> at the very least, we should be using the SI designation in user
> visible strings?
> 
> It may also be worth providing a brief description of 10BASE-T1L in the
> cover letter so (e.g.) one doesn't have to look up the fact that the
> voltage level is negotiated via bit 13 of the base page. I've found
> that by searching google and finding dp83td510e.pdf

I'm curios how the voltage should be actually chosen?

In the adin1100 datasheet i read:
"The 1.0 V pk-pk operating mode, external termination resistors and independent
Rx/Tx pins make the ADIN1100 suited to intrinsic safety applications"

"For long reach/trunk applications the higher transmit amplitude of 2.4 V pk-pk"

So, it seems to depends on:
- do we have safety requirements?
- how long is the cable?

Can we use 2.4V any time if it is available or it is bad idea for short
cables?

Regards,
Oleksij
-- 
Pengutronix e.K.                           |                             |
Steuerwalder Str. 21                       | http://www.pengutronix.de/  |
31137 Hildesheim, Germany                  | Phone: +49-5121-206917-0    |
Amtsgericht Hildesheim, HRA 2686           | Fax:   +49-5121-206917-5555 |