linux-kernel - RE: [EXT] Re: [PATCH] i2c: pca954x: Add property to skip disabling PCA954x MUX device

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:   Mon, 30 Sep 2019 02:48:04 +0000
From:   Biwen Li <biwen.li@....com>
To:     "cengiz@...nel.wtf" <cengiz@...nel.wtf>
CC:     "linux-i2c@...r.kernel.org" <linux-i2c@...r.kernel.org>,
        "linux-kernel@...r.kernel.org" <linux-kernel@...r.kernel.org>,
        "peda@...ntia.se" <peda@...ntia.se>, Leo Li <leoyang.li@....com>,
        Wolfram Sang <wsa@...-dreams.de>
Subject: RE: [EXT] Re: [PATCH] i2c: pca954x: Add property to skip disabling
 PCA954x MUX device

> 
> Hello Biwen,
> 
> > +       /* Errata ID E-00013 on board LS2088ARDB and LS2088ARDB:
> > +        * The point here is that you must not disable a mux if there
> > +        * are no pullups on the input or you mess up the I2C. This
> > +        * needs to be put into the DTS really as the kernel cannot
> > +        * know this otherwise.
> > +        */
> 
> Can you please explain what a "mess up" is?
This is a hardware bug that happened on NXP board LS2085ARDB and LS2088ARDB.
So give a software fix for the hardware bug.
> 
> And also, should we put this new DTS property in related default bindings?
> 
> If not, are you planning a documentation update for the users to notify them
> about this?
I will update bindings document on v2.
> 
> --
> Cengiz Can <cengiz@...nel.wtf>