Re: [PATCH 3/3 v2] iio: add rtc-driver for HID sensors of type time

[Alan Cox <alan@lxorguk.ukuu.org.uk>]

On Tue, 11 Dec 2012 01:01:29 +0100
Alexander Holler <holler@ahsoftware.de> wrote:

> Am 10.12.2012 23:36, schrieb Lars-Peter Clausen:
> > Well, I've been exaggerating a bit, you can call it multiple times, but you
> 
> Thanks a lot for the explanation(s).
> 
> >>>> +error_free_drvdata:
> >>>> +    platform_set_drvdata(pdev, NULL);
> >>>
> >>> Setting the platform data to NULL should not be necessary. Some
> >>> drivers do
> >>> this but it's kind of the result of cargo-cult-coding.
> >>>
> >>>> +    kfree(time_state);
> 
> Btw. I wouldn't call that cargo-cult-coding. It's more defensive 
> programming as people might not be sure, if there is something around 
> which still might access the platform data at that point. Ok, there 
> would be a need for a mutex or similiar if that really could happen, but 
> I wouldn't call such practices cargo-cult. ;)

Agreed - pointer NULLing catches a lot of mistakes during teardown where
timers or interrupts running in parallel get missed.

Alan