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

From: Tony Lindgren
Date: Tue Apr 24 2012 - 12:04:52 EST


* DebBarma, Tarun Kanti <tarun.kanti@xxxxxx> [120424 08:40]:
> Hi Janusz,
>
> On Tue, Apr 24, 2012 at 12:24 AM, DebBarma, Tarun Kanti
> <tarun.kanti@xxxxxx> wrote:
> > On Sat, Apr 21, 2012 at 7:33 PM, Janusz Krzysztofik
> > <jkrzyszt@xxxxxxxxxxxx> 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@xxxxxx>
> >>> Signed-off-by: Charulatha V <charu@xxxxxx>
> >>> Reviewed-by: Santosh Shilimkar <santosh.shilimkar@xxxxxx>
> >>> Acked-by: Tony Lindgren <tony@xxxxxxxxxxx>
> >>
> >> 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@xxxxxx>
> 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?

> 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.

Regards,

Tony


> Signed-off-by: Tarun Kanti DebBarma <tarun.kanti@xxxxxx>
> ---
> drivers/gpio/gpio-omap.c | 5 +----
> 1 files changed, 1 insertions(+), 4 deletions(-)
>
> diff --git a/drivers/gpio/gpio-omap.c b/drivers/gpio/gpio-omap.c
> index 1adc2ec..b8f01c1 100644
> --- a/drivers/gpio/gpio-omap.c
> +++ b/drivers/gpio/gpio-omap.c
> @@ -964,11 +964,8 @@ static void omap_gpio_mod_init(struct gpio_bank *bank)
> return;
> }
>
> + _gpio_rmw(base, bank->regs->irqstatus, l,
> bank->regs->irqenable_inv == 0 );
> _gpio_rmw(base, bank->regs->irqenable, l, bank->regs->irqenable_inv);
> - _gpio_rmw(base, bank->regs->irqstatus, l,
> - bank->regs->irqenable_inv == false);
> - _gpio_rmw(base, bank->regs->irqenable, l, bank->regs->debounce_en != 0);
> - _gpio_rmw(base, bank->regs->irqenable, l, bank->regs->ctrl != 0);
> if (bank->regs->debounce_en)
> _gpio_rmw(base, bank->regs->debounce_en, 0, 1);
>
> --
> 1.7.0.4


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