Re: [PATCH] gpio/generic: initialize the shadow of direction register

Grant Likely <grant.likely@xxxxxxxxxxxx> · Thu, 17 May 2012 14:39:14 -0600

On Thu, 17 May 2012 00:17:27 +0800, Shawn Guo <shawn.guo@xxxxxxxxxxxxx> wrote:
> On Wed, May 16, 2012 at 03:54:37PM +0200, Lothar WaÃ?mann wrote:
> > Actually I had sent a similar patch in July last year which was
> > rejected with the following reasoning:
> > 
> > | I don't know if this is a valid thing to do or not. Not every GPIO
> > | controller supports reading back the initial state from the direction
> > | register. I suspect it is better to leave initialization of the
> > | direction to the gpio controller driver itself.
> > 
> > See: http://lkml.indiana.edu/hypermail/linux/kernel/1107.0/00908.html
> > 
> > That's why I came up with the patch to gpio-mxc.c
> > 
> Thanks for the whole story, Lothar.  Hopefully, with the additional
> condition checking added, Grant would agree it's the right thing to do.
> I will send v2 of the patch to see what we get from people.

Yup, if there was some kind of conditional checking then it would be
fine.

g.