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From: Linus Walleij <linus.walleij@linaro.org>
Date: Tue, 7 May 2024 12:00:10 +0200
Message-ID: <CACRpkdbHKPBT087WZ8PN4Mb6pLLAuFLufFw69vn5cimWJmwchA@mail.gmail.com>
Subject: Re: [PATCH v3 4/5] PCI: imx6: Convert to agnostic GPIO API
To: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
Cc: Andy Shevchenko <andriy.shevchenko@linux.intel.com>, Frank Li <Frank.Li@nxp.com>, 
	=?UTF-8?Q?Krzysztof_Wilczy=C5=84ski?= <kwilczynski@kernel.org>, 
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On Tue, May 7, 2024 at 10:28=E2=80=AFAM Manivannan Sadhasivam
<manivannan.sadhasivam@linaro.org> wrote:
> On Tue, May 07, 2024 at 01:44:56PM +0530, Manivannan Sadhasivam wrote:
> > On Mon, May 06, 2024 at 02:10:24PM +0200, Linus Walleij wrote:
> > > On Mon, Apr 29, 2024 at 12:25=E2=80=AFPM Andy Shevchenko
> > > <andriy.shevchenko@linux.intel.com> wrote:
> > >
> > > > The of_gpio.h is going to be removed. In preparation of that conver=
t
> > > > the driver to the agnostic API.
> > > >
> > > > Reviewed-by: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.or=
g>
> > > > Reviewed-by: Frank Li <Frank.Li@nxp.com>
> > > > Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
> > >
> > > I think there is a bug here, the code is respecting the OF property
> > > "reset-gpio-active-high"
> > > but the code in drivers/gpio/gpiolib-of.h actually has a quirk for
> > > this so you can just
> > > delete all the active high handling and rely on 1 =3D asserted and 0 =
=3D
> > > deasserted when
> > > using GPIO descriptors.
> > >
> >
> > Wow...
> >
> > So this bug is present even before this series, right?
> >
> > > Just delete this thing:
> > > imx6_pcie->gpio_active_high =3D of_property_read_bool(node,
> > >                                            "reset-gpio-active-high");
> >
> > But this is just a bandaid IMO. The flag for the PERST# GPIO should be =
properly
> > set in the board dts as per the board design.
> >
>
> Hmm, no. I was confused by the property. But this quirk in gpiolib-of.c i=
s going
> to be applied while changing the GPIO state also or just during request t=
ime?

It's applied permanentlt at request and then the descriptors maintain their
polarity state over the course of their lifetime.

Yours,
Linus Walleij