linux-kernel - Re: [PATCH] pinctrl: intel: Initialize GPIO properly when used through irqchip

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]

Date:   Wed, 29 Nov 2017 13:39:00 +0100
From:   Linus Walleij <linus.walleij@...aro.org>
To:     Mika Westerberg <mika.westerberg@...ux.intel.com>
Cc:     Heikki Krogerus <heikki.krogerus@...ux.intel.com>,
        Daniel Drake <drake@...lessm.com>,
        Chris Chiu <chiu@...lessm.com>,
        Andy Shevchenko <andriy.shevchenko@...ux.intel.com>,
        linux-gpio@...r.kernel.org,
        "linux-kernel@...r.kernel.org" <linux-kernel@...r.kernel.org>
Subject: Re: [PATCH] pinctrl: intel: Initialize GPIO properly when used
 through irqchip

On Mon, Nov 20, 2017 at 4:19 PM, Mika Westerberg
<mika.westerberg@...ux.intel.com> wrote:

> When a GPIO is requested using gpiod_get_* APIs the intel pinctrl driver
> switches the pin to GPIO mode and makes sure interrupts are routed to
> the GPIO hardware instead of IOAPIC. However, if the GPIO is used
> directly through irqchip, as is the case with many I2C-HID devices where
> I2C core automatically configures interrupt for the device, the pin is
> not initialized as GPIO. Instead we rely that the BIOS configures the
> pin accordingly which seems not to be the case at least in Asus X540NA
> SKU3 with Focaltech touchpad.
>
> When the pin is not properly configured it might result weird behaviour
> like interrupts suddenly stop firing completely and the touchpad stops
> responding to user input.
>
> Fix this by properly initializing the pin to GPIO mode also when it is
> used directly through irqchip.
>
> Reported-by: Daniel Drake <drake@...lessm.com>
> Reported-by: Chris Chiu <chiu@...lessm.com>
> Signed-off-by: Mika Westerberg <mika.westerberg@...ux.intel.com>

Should this have a Fixes:?

Should this have a Cc: stable@...r.kernel.org?

> Chris, Daniel,
>
> Could you check that this still solves the issue and maybe provide your
> Tested-by? Thanks!

Pls pick up Tested-by's when resending.

> +static void __intel_gpio_init_gpio(void __iomem *padcfg0)

I just don't like __underscore_means_inner_function() I
strongly prefer function_has_a_proper_name() so please
come up with something that describes what it is really doing
and name it like that.

With that fixes, I'll apply it pronto.

Yours,
Linus Walleij