linux-kernel - Re: [PATCH 0/2] i2c: Don't assume bus nr 0 if none was specified

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 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:	Sat, 17 Mar 2012 10:50:56 +0000
From:	Grant Likely <grant.likely@...retlab.ca>
To:	Karol Lewandowski <k.lewandowsk@...sung.com>, w.sang@...gutronix.de
Cc:	ben-linux@...ff.org, khali@...ux-fr.org, linux-i2c@...r.kernel.org,
	linux-kernel@...r.kernel.org, hskinnemoen@...il.com,
	dirk.brandewie@...il.com, bigeasy@...utronix.de,
	m.szyprowski@...sung.com, kyungmin.park@...sung.com
Subject: Re: [PATCH 0/2] i2c: Don't assume bus nr 0 if none was specified

On Fri, 16 Mar 2012 13:27:27 +0100, Karol Lewandowski <k.lewandowsk@...sung.com> wrote:
> On 16.03.2012 13:19, Karol Lewandowski wrote:
> 
> > Hi,
> > 
> > i2c controller drivers used to assume bus number 0 when none (-1) was specified.
> > 
> > This worked on non-device tree systems, where one could explicitly specify
> > bus number via platform data.  On DT-enabled systems bus number is always -1.
> > 
> > Some drivers assume bus number 0 when -1 is specified.  This patchset kills
> > this logic and switches to dynamic bus allocation (default when -1 is provided[1]).
> 
> 
> [ I must have lost actual problem description while rewording
>   message itself... ]
> 
> Problem arises when multiple drivers (or multiple instances
> of one driver) try to assume the same fixed bus number (0).
> 
> This causes simply causes i2c_add_numbered_bus() to fail.
> Leaving -1 works perfectly, as registration function switches
> to dynamic id registration.

Patch series looks good to me.  You'll need acks from the affected users.

g.

--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/