Re: [ACPI] Re: [PATCH] filling in ACPI method access via sysfs namespace

[Andy Lutomirski <luto@myrealbox.com>]

Alex Williamson wrote:

> On Sun, 2004-04-11 at 16:29, Matthew Wilcox wrote:
> 
>>It seems unintuitive that you have to read the file for the method to
>>take effect.  How about having the write function invoke the method and
>>(if there is a result) store it for later read-back via the read function?
>>It should be discarded on close, of course.  A read() on a file with
>>no stored result should invoke the ACPI method (on the assumption this
>>is a parameter-less method) and return the result directly.  Closing a
>>file should discard any result from the method.
> 
> 
>    How's this?  It behaves the way you described, but might be doing
> some questionable things with the buffer to get there.  Is there a
> better place to store the return data than back into the buf passed to
> write() (aka file->private_data)?  Without adding callbacks to
> open/close, I'm not sure how else we can dispose of the results on
> close.  Thanks,

Is there any reason this shouldn't be an ioctl?

--Andy