Attr Groups in sysfs.
Gasparini Andrea
gaspa at yattaweb.it
Mon Apr 18 10:29:57 EDT 2011
Hi,
On Mon, Apr 18, 2011 at 4:14 PM, Greg KH <greg at kroah.com> wrote:
>> I'm missing only the myattr_group name... anyone has a clue of how can
>> I access this?
>
> You can't.
ok.
>> And adding to my kobject this way:
>> retval = sysfs_create_group(mykobj, &my_attr_group_0);
>
> Ick, no, please don't do that, you want the group to be created before
> the device shows up to userspace, otherwise you just raced with
> userspace and bad things will happen.
Understand, you're completely right.
I'll try to refactor in a different way to avoid race.
> Why are you using a struct kobject directly and not a struct device
> instead? Please don't use kobjects unless you are doing something very
> strange, and even then, please reconsider.
>
> Care to explain what you are using sysfs for?
Sure, It's quite complicated, in fact ;)
I'm doing an "extension" for a video device, in terms of a module that
handle some addictional logic that do some sort of stats about the
stream passed through it.
For example, I've a certain number of areas inside a frame, given in
form of (x,y,width,heigth) that behave to the same device, so I'd like
to call them: mydev/region_{0,1,2...}/{x,y,width,height}
That's why I'd like to have the "region_0" name, so I can distinguish
between the right attribute group.
Too caotic perhaps? (suggestions and existing examples are obviuosly welcome)
> thanks,
Thank *you* ;)
bye
--
-gaspa-
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