Re: [PATCH] Platform lockdown information in SYSFS

[Greg Kroah-Hartman]

On Tue, Aug 04, 2020 at 10:50:13AM -0300, Daniel Gutson wrote:
> On Tue, Aug 4, 2020 at 3:41 AM Greg Kroah-Hartman
> <gregkh@xxxxxxxxxxxxxxxxxxx> wrote:
> >
> > On Mon, Aug 03, 2020 at 07:04:56PM -0300, Daniel Gutson wrote:
> > > > > > Think of this as an input device.  You don't put the random input
> > > > > > attributes all in one place, you create a new device that represents the
> > > > > > input interface and register that.
> > >
> > > I'm having trouble with this. What's the dev_t for the child devices?
> > > I'm doing
> > >     child_device = device_create(&my_class, &pdev->dev, MKDEV(0, 0),
> > > NULL, "child");
> > > pdev is the pci_device (intel-spi-pci)
> > > dmesg shows
> > >
> > >     sysfs: cannot create duplicate filename '/class/my-class'
> > >     (call trace)
> > >     kobject_add_internal failed for my-class with -EEXIST, don't try
> > > to register things with the same name in the same directory.
> >
> > Without seeing all of your code, I can't tell you what you are doing
> > wrong, but the kernel should be giving you a huge hint here...
> >
> > Don't create duplicate names in the same subdirectory.
> 
> I'm not doing that. One of my questions is if MKDEV(0, 0) is valid for
> create_device, which I inferred so from the documentation.

Yes it is, but that's not the error given to you :)

Many in-kernel users call device_create() with MKDEV(0, 0)

> Here is the listing

<snip>

It's not in any format to read, please never strip leading whitespace,
it hurts my brain...

thanks,

greg k-h