Messages in this thread |  | | Date | Tue, 17 Feb 2015 20:57:45 -0800 | From | Greg Kroah-Hartman <> | Subject | Re: [PATCH 2/2 v3] drivers/core/of: Add symlink to device-tree from devices with an OF node |
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On Wed, Feb 18, 2015 at 11:25:18AM +1100, Benjamin Herrenschmidt wrote: > So I've been annoyed lately with having a bunch of devices such as i2c > eeproms (for use by VPDs, server world !) and other bits and pieces that > I want to be able to identify from userspace, and possibly provide > additional data about from FW. > > Basically, it boils down to correlating the sysfs device with the OF > tree device node, so that user space can use device-tree info such as > additional "location" or "label" (or whatever else we can come up with) > propreties to identify a given device, or get some attributes of use > about it, etc... > > Now, so far, we've done that in some subsystem in a fairly ad-hoc basis > using "devspec" properties. For example, PCI creates them if it can > correlate the probed device with a DT node. Some powerpc specific busses > do that too. > > However, i2c doesn't and it would be nice to have something more generic > since technically any device can have a corresponding device tree node. > > This patch adds an "of_node" symlink to devices that have a non-NULL > dev->of_node pointer, the patch is pretty trivial and seems to work just > fine for me. > > Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org> > --- > > This addresses Greg's comments. Note that I'm not 100% certain about > using device_add_class_symlinks(), I had to put the code before the > test for dev->class, maybe we should rename that function to device_add_symlinks() > if it grows beyond the class bits ?
That would probably be a good idea, but we can leave it for now.
> Also there was nothing that I could find in Documentation/ABI that > documented "core" device properties, it's all in > Documentation/sysfs-rules.txt, but as suggested by Greg (on IRC) I > went for ABI anyway, so I've added a file for "generic" properties > and added that one in. I'm happy to change it if you think that's not > right, just let me know where you want things.
It looks good as-is, thanks.
greg k-h
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