lists.openwall.net   lists  /  announce  owl-users  owl-dev  john-users  john-dev  passwdqc-users  yescrypt  popa3d-users  /  oss-security  kernel-hardening  musl  sabotage  tlsify  passwords  /  crypt-dev  xvendor  /  Bugtraq  Full-Disclosure  linux-kernel  linux-netdev  linux-ext4  linux-hardening  linux-cve-announce  PHC 
Open Source and information security mailing list archives
 
Hash Suite: Windows password security audit tool. GUI, reports in PDF.
[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]
Message-ID: <20221122081851.6cb762d8@erd992>
Date:   Tue, 22 Nov 2022 08:18:51 +0100
From:   David Jander <david@...tonic.nl>
To:     Fabio Estevam <festevam@...il.com>
Cc:     Quentin Schulz <foss+kernel@...il.net>,
        "Angus Ainslie (Purism)" <angus@...ea.ca>,
        Shawn Guo <shawnguo@...nel.org>,
        Krzysztof Kozlowski <krzysztof.kozlowski+dt@...aro.org>,
        Heiko Stuebner <heiko@...ech.de>,
        Samuel Holland <samuel@...lland.org>,
        Bjorn Andersson <andersson@...nel.org>,
        Konrad Dybcio <konrad.dybcio@...ainline.org>,
        Jernej Skrabec <jernej.skrabec@...il.com>,
        Bastien Nocera <hadess@...ess.net>,
        Chen-Yu Tsai <wens@...e.org>,
        Sascha Hauer <s.hauer@...gutronix.de>,
        Pengutronix Kernel Team <kernel@...gutronix.de>,
        Hans de Goede <hdegoede@...hat.com>,
        Andy Gross <agross@...nel.org>,
        Rob Herring <robh+dt@...nel.org>,
        NXP Linux Team <linux-imx@....com>,
        Dmitry Torokhov <dmitry.torokhov@...il.com>,
        Quentin Schulz <quentin.schulz@...obroma-systems.com>,
        linux-kernel@...r.kernel.org, linux-rockchip@...ts.infradead.org,
        linux-arm-msm@...r.kernel.org, linux-input@...r.kernel.org,
        linux-arm-kernel@...ts.infradead.org, linux-sunxi@...ts.linux.dev,
        devicetree@...r.kernel.org
Subject: Re: [PATCH RFC v2 5/7] arm64: dts: imx: fix touchscreen reset GPIO
 polarity

On Mon, 21 Nov 2022 15:18:32 -0300
Fabio Estevam <festevam@...il.com> wrote:

> [Adding Angus and David]

Thanks. This was apparently necessary ;-)

> On Mon, Nov 21, 2022 at 3:12 PM Quentin Schulz <foss+kernel@...il.net> wrote:
> >
> > From: Quentin Schulz <quentin.schulz@...obroma-systems.com>
> >
> > The reset line is active low for the Goodix touchscreen controller so
> > let's fix the polarity in the Device Tree node.
> >
> > Signed-off-by: Quentin Schulz <quentin.schulz@...obroma-systems.com>
> > ---
> >  arch/arm64/boot/dts/freescale/imx8mm-prt8mm.dts         | 2 +-
> >  arch/arm64/boot/dts/freescale/imx8mq-librem5-devkit.dts | 2 +-
> >  2 files changed, 2 insertions(+), 2 deletions(-)
> >
> > diff --git a/arch/arm64/boot/dts/freescale/imx8mm-prt8mm.dts b/arch/arm64/boot/dts/freescale/imx8mm-prt8mm.dts
> > index 9fbbbb556c0b3..df7e5ae9698e1 100644
> > --- a/arch/arm64/boot/dts/freescale/imx8mm-prt8mm.dts
> > +++ b/arch/arm64/boot/dts/freescale/imx8mm-prt8mm.dts
> > @@ -107,7 +107,7 @@ touchscreeen@5d {
> >                 interrupt-parent = <&gpio1>;
> >                 interrupts = <8 IRQ_TYPE_NONE>;
> >                 irq-gpios = <&gpio1 8 GPIO_ACTIVE_HIGH>;
> > -               reset-gpios = <&gpio1 9 GPIO_ACTIVE_HIGH>;
> > +               reset-gpios = <&gpio1 9 GPIO_ACTIVE_LOW>;

NACK!

The PRT8MM has an inverter in the reset line. The reason for that is that the
reset line needs to be inactive when the driving side is unpowered.
The DT was correct, this change will break it.

> >         };
> >
> >         temp-sense@70 {
> > diff --git a/arch/arm64/boot/dts/freescale/imx8mq-librem5-devkit.dts b/arch/arm64/boot/dts/freescale/imx8mq-librem5-devkit.dts
> > index 6445c6b90b5bb..b038300812b1e 100644
> > --- a/arch/arm64/boot/dts/freescale/imx8mq-librem5-devkit.dts
> > +++ b/arch/arm64/boot/dts/freescale/imx8mq-librem5-devkit.dts
> > @@ -542,7 +542,7 @@ touchscreen@5d {
> >                 pinctrl-0 = <&pinctrl_ts>;
> >                 interrupt-parent = <&gpio3>;
> >                 interrupts = <0 IRQ_TYPE_LEVEL_LOW>;
> > -               reset-gpios = <&gpio1 5 GPIO_ACTIVE_HIGH>;
> > +               reset-gpios = <&gpio1 5 GPIO_ACTIVE_LOW>;
> >                 irq-gpios = <&gpio3 0 GPIO_ACTIVE_HIGH>;
> >                 touchscreen-size-x = <720>;
> >                 touchscreen-size-y = <1440>;
> >
> > --
> > b4 0.10.1  

Best regards,

-- 
David Jander
Protonic Holland.

Powered by blists - more mailing lists

Powered by Openwall GNU/*/Linux Powered by OpenVZ