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Subject: Re: [Ubi] Wrong major:minor
From: Artem Bityutskiy <dedekind1@gmail.com>
To: Gilles <gilles.ganault@free.fr>
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Date: Wed, 01 Jun 2011 11:29:23 +0300
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Cc: linux-mtd@lists.infradead.org, Mike Frysinger <vapier.adi@gmail.com>
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On Sun, 2011-05-29 at 11:54 -0400, Mike Frysinger wrote:
> On Sun, May 29, 2011 at 06:39, Gilles wrote:
> > I'm no Linux expert, and was wondering how to find out what the
> > correct major:minor is for the Ubi device nodes?
> 
> they're most likely dynamic and there's no safe way you could create
> the nodes ahead of time with a device table.  simply run mdev to take
> care of /dev for you.
> 
> you can check /proc/devices to be sure ... anything over 250 is dynamic
> -mike

Right, UBI allocates device numbers dynamically, so pre-creating device
nodes is not a good idea.

Major/minor for every UBI device / UBI volume can be found at:

/sys/class/ubi/ubiX/dev
/sys/class/ubi/ubiX_Y/dev

Or the major number can be indeed found at /proc/devices, and then the
minor numbers follow the following fomula:

UBI Volume major number = UBI device major number.
UBI Volume minor number = UBI volume ID + 1.

-- 
Best Regards,
Artem Bityutskiy (Артём Битюцкий)