From mboxrd@z Thu Jan 1 00:00:00 1970 From: Arnout Vandecappelle Date: Fri, 22 Feb 2013 00:24:11 +0100 Subject: [Buildroot] editing device_table_dev.txt In-Reply-To: <5126A8C7.2000009@petroprogram.com> References: <1361403460.22521.44.camel@genx.eng.msli.com> <5125F38B.2030204@petroprogram.com> <5125F50C.7020902@petroprogram.com> <20130221102315.GB12155@sapphire.tkos.co.il> <5125F7BB.50403@petroprogram.com> <5126A675.2060308@mind.be> <5126A8C7.2000009@petroprogram.com> Message-ID: <5126AC9B.30302@mind.be> List-Id: MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: buildroot@busybox.net On 22/02/13 00:07, Stefan Fr?berg wrote: > 22.2.2013 0:57, Arnout Vandecappelle kirjoitti: >> On 21/02/13 11:32, Stefan Fr?berg wrote: >>>>>>>>> Also kernel .config file should also have CONFIG_DEVTMPFS and >>>>>> DEVTMPFS >>>>>>>>> as 'y'. >>>>>>> Sorry, that should have been CONFIG_DEVTMPFS=y and >>>>> CONFIG_DEVTMPFS_MOUNT=y >>>>> Kernel version 2.6.30 is too old for that. >>>>> >>>>> baruch >>>>> >>> It is ? >>> Damn, then the only options are mdev and udev. >> >> I'm afraid that mdev and udev no longer work with old kernels that >> don't support the DEVTMPFS option... >> >> mdev and udev don't create device nodes; they only do something >> configurable when a hotplug event happens. >> > > What you mean that mdev or udev does not create device nodes ??? > If older kernels don't support devtmpfs like Baruch > said then who does that device node creation if not the mdev or udev > when event happens ??? Well, nobody... Turns out that mdev still does device node creation. Makes me wonder if I'm not mistaken about udev as well... I just remember hearing that device node creation was removed when DEVTMPFS was introduced. >> That said, you can create custom mdev/udev rules to create device >> nodes. But it's all manual - and much simpler to just create the >> device nodes manually. >> > > for mdev it's just a single file, /etc/mdev.conf (I can even copy-paste > it here, it's not that long and will cover 99% of needs). Yes, but that file just specifies the chmod/chown rules, not how to create the device nodes. But as I just saw in the code, mdev does in fact create the device nodes. Regards, Arnout > for udev it punch of rules found under /lib/udev/rules.d and yes, it can > get really tedious to play games with those files if some device node is > not created or > is not created with right permissions or whatever. [snip] -- Arnout Vandecappelle arnout at mind be Senior Embedded Software Architect +32-16-286500 Essensium/Mind http://www.mind.be G.Geenslaan 9, 3001 Leuven, Belgium BE 872 984 063 RPR Leuven LinkedIn profile: http://www.linkedin.com/in/arnoutvandecappelle GPG fingerprint: 7CB5 E4CC 6C2E EFD4 6E3D A754 F963 ECAB 2450 2F1F