From mboxrd@z Thu Jan  1 00:00:00 1970
From: Greg KH <greg@kroah.com>
Date: Tue, 26 Jan 2010 15:22:29 +0000
Subject: Re: Order of DVB devices
Message-Id: <20100126152229.GA3113@kroah.com>
List-Id: <linux-hotplug.vger.kernel.org>
References: <4B5EFDF7.8090709@motama.com>
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To: linux-hotplug@vger.kernel.org

On Tue, Jan 26, 2010 at 03:36:39PM +0100, Andreas Besse wrote:
> Hello,
> 
> i have a system with multiple DVB cards of the same type and want to
> specify the order of the devices /dev/dvb/adapterX. The device plugged
> into the physical PCI slot 1 on the mainboard should be assigned to
> /dev/dvb/adapter0 and the card in PCI slot 2 should be assigned to
> /dev/dvb/adapter1.
> 
> To identify a DVB card I looked at the output of udevinfo for 2 DVB
> devices. The devices don't provide a serial, so the difference is only
> in the KERNELS parameter (e.g. KERNELS="0000:02:00.0" vs.
> KERNELS="0000:03:00.0"). The Kernels parameter seem to reflect the PCI
> Bus ID.
> 
> According to the thread
> http://thread.gmane.org/gmane.linux.kernel.pci/7446/focust47 on the
> linux-pci mailinglist, the PCI Bus ID is *not* deterministic and
> totally random determined at boot. 
> 
> In the following post
> http://thread.gmane.org/gmane.linux.kernel.pci/7446/focust67 there
> is mentioned that the order of the devices can be specified by using
> udev rules.
> 
> But how this can be done? Which information in /sys can be used to
> determine which DVB device is connected to which specific slot?

Did you try the latest version of udev that has the persistant rules for
the v4l devices in it and look at the symlinks that are created to see
if they solve the problem for you?

thanks,

greg k-h