[PATCH v9 11/25] gpio/omap: cleanup omap_gpio_mod_init function

[Russell King - ARM Linux]

On Wed, Apr 25, 2012 at 06:24:14PM +0530, DebBarma, Tarun Kanti wrote:
> On Wed, Apr 25, 2012 at 12:09 PM, Shilimkar, Santosh
> <santosh.shilimkar at ti.com> wrote:
> > On Wed, Apr 25, 2012 at 10:04 AM, DebBarma, Tarun Kanti
> > <tarun.kanti at ti.com> wrote:
> >> On Tue, Apr 24, 2012 at 9:34 PM, Tony Lindgren <tony at atomide.com> wrote:
> >>> * DebBarma, Tarun Kanti <tarun.kanti at ti.com> [120424 08:40]:
> >>>> Hi Janusz,
> >>>>
> >>>> On Tue, Apr 24, 2012 at 12:24 AM, DebBarma, Tarun Kanti
> >>>> <tarun.kanti at ti.com> wrote:
> >>>> > On Sat, Apr 21, 2012 at 7:33 PM, Janusz Krzysztofik
> >>>> > <jkrzyszt at tis.icnet.pl> wrote:
> >>>> >> On Thursday 02 of February 2012 23:00:37 Tarun Kanti DebBarma wrote:
> >>>> >>> With register offsets now defined for respective OMAP versions we can get rid
> >>>> >>> of cpu_class_* checks. This function now has common initialization code for
> >>>> >>> all OMAP versions...
> >>>> >>>
> >>>> >>> Signed-off-by: Tarun Kanti DebBarma <tarun.kanti at ti.com>
> >>>> >>> Signed-off-by: Charulatha V <charu at ti.com>
> >>>> >>> Reviewed-by: Santosh Shilimkar <santosh.shilimkar at ti.com>
> >>>> >>> Acked-by: Tony Lindgren <tony at atomide.com>
> >>>> >>
> >>>> >> Sorry for being so late with my comment for chanes already present in
> >>>> >> mainline, but this patch breaks GPIO on Amstrad Delta at least, and I
> >>>> >> have neither enough spare time nor enough experience with non OMAP1
> >>>> >> machines to provide a solution myself.
> >>>> > Yes, I looked at the omap_gpio_mod_init() and OMAP1 configurations are
> >>>> > overwritten.
> >>>> > Also looks like there is issue in making distinction between omap15xx
> >>>> > and omap16xx.
> >>>> > I will post a patch and you can help me testing it in OMAP1 platform.
> >>>> > Thanks for pointing this out.
> >>> ...
> >>>
> >>>> Here is the patch, with attachment as well. I have just tested on
> >>>> OMAP4 platform.
> >>>> Testing on other OMAP2+ platforms is pending. In the meantime can you please
> >>>> validate on OMAP1 platform and confirm? Thanks.
> >>>> --
> >>>> Tarun
> >>>>
> >>>> From: Tarun Kanti DebBarma <tarun.kanti at ti.com>
> >>>> Date: Tue, 24 Apr 2012 20:34:32 +0530
> >>>> Subject: [PATCH] gpio/omap: fix omap1 register overwrite in omap_gpio_mod_init
> >>>>
> >>>> Initialization of irqenable, irqstatus registers is the common
> >>>> operation done in this function for all OMAP platforms, viz.
> >>>> OMAP1, OMAP2+. The latter _gpio_rmw()'s to irqenable register
> >>>> was overwriting the correctly programmed OMAP1 value at the
> >>>> beginning. As a result, even though it worked on OMAP2+
> >>>> platforms it was breaking OMAP1 functionality.
> >>>
> >>> Sounds like the original patch was never tested on omap1?
> >> That's right, only bootup test was done on OMAP1710-SDP.
> >>
> >>>
> >>>> On closer observation it is found that the first _gpio_rmw()
> >>>> which is supposedly done to take care of OMAP1 platform is
> >>>> generic enough and takes care of OMAP2+ platform as well.
> >>>> Therefore remove the latter _gpio_rmw() to irqenable as they
> >>>> are redundant.
> >>>>
> >>>> Also, changing the sequence and logic of initializing the
> >>>> irqstatus.
> >>>
> >>> Please mention also the breaking commit here and get this fix
> >>> merged as a regression as soon as it's tested for the current
> >>> -rc series.
> >> Sure, I will do that!
> >
> > Looks like it is regression on 3.4 as well so CC stable when you
> > post the patch.
> Ok, I will do that.

Correction.

Don't email your patch in any way to the stable folk _before_ it has been
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But... make sure that git send-email or whatever doesn't automatically
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If you send the stable people a patch before its in mainline, you'll get
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