linux-kernel - Re: [PATCH 1/9] pinctrl: sunxi: Support I/O bias voltage setting on A80

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 for Android: free password hash cracker in your pocket

[<prev] [next>] [<thread-prev] [day] [month] [year] [list]

Date:   Wed, 13 Feb 2019 19:31:58 +0800
From:   Chen-Yu Tsai <wens@...e.org>
To:     Linus Walleij <linus.walleij@...aro.org>
Cc:     Maxime Ripard <maxime.ripard@...tlin.com>,
        Linux ARM <linux-arm-kernel@...ts.infradead.org>,
        "open list:GPIO SUBSYSTEM" <linux-gpio@...r.kernel.org>,
        "open list:OPEN FIRMWARE AND FLATTENED DEVICE TREE BINDINGS" 
        <devicetree@...r.kernel.org>,
        "linux-kernel@...r.kernel.org" <linux-kernel@...r.kernel.org>,
        linux-sunxi <linux-sunxi@...glegroups.com>,
        Corentin Labbe <clabbe@...libre.com>
Subject: Re: [PATCH 1/9] pinctrl: sunxi: Support I/O bias voltage setting on A80

On Mon, Feb 11, 2019 at 4:21 PM Linus Walleij <linus.walleij@...aro.org> wrote:
>
> On Wed, Feb 6, 2019 at 4:32 AM Chen-Yu Tsai <wens@...e.org> wrote:
>
> > The A80 SoC has configuration registers for I/O bias voltage. Incorrect
> > settings would make the affected peripherals inoperable in some cases,
> > such as Ethernet RGMII signals biased at 2.5V with the settings still
> > at 3.3V. However low speed signals such as MDIO on the same group of
> > pins seem to be unaffected.
> >
> > Previously there was no way to know what the actual voltage used was,
> > short of hard-coding a value in the device tree. With the new pin bank
> > regulator supply support in place, the driver can now query the
> > regulator for its voltage, and if it's valid (as opposed to being the
> > dummy regulator), set the bias voltage setting accordingly.
> >
> > Add a quirk to denote the presence of the configuration registers, and
> > a function to set the correct setting based on the voltage read back
> > from the regulator.
> >
> > This is only done when the regulator is first acquired and enabled.
> > While it would be nice to have a notifier on the regulator so that when
> > the voltage changes, the driver can update the setting, in practice no
> > board currently supports dynamic changing of the I/O voltages.
> >
> > Signed-off-by: Chen-Yu Tsai <wens@...e.org>
>
> I merged the v5.0-rc6 into my devel branch and applied this patch on
> top now.
>
> All the DTS file changes should be merged through ARM SoC, and
> they should work fine now.

Thanks. Maxime actually merged them last week.

It seems this isn't in -next yet. I'm not seeing it in your git.kernel.org
repo either. Might be confusing for others that want to try it out.

ChenYu