Linux-ACPI Archive on
 help / color / Atom feed
From: Linus Walleij <>
To: Hans de Goede <>
Cc: Mika Westerberg <>,
	Andy Shevchenko <>,
	Bartosz Golaszewski <>,
	"open list:GPIO SUBSYSTEM" <>,
	ACPI Devel Maling List <>,
	stable <>,
	Daniel Drake <>,
Subject: Re: [PATCH v2] gpiolib: acpi: Add gpiolib_acpi_run_edge_events_on_boot option and blacklist
Date: Wed, 11 Sep 2019 10:48:39 +0100
Message-ID: <> (raw)
In-Reply-To: <>

On Tue, Aug 27, 2019 at 9:28 PM Hans de Goede <> wrote:

> Another day; another DSDT bug we need to workaround...
> Since commit ca876c7483b6 ("gpiolib-acpi: make sure we trigger edge events
> at least once on boot") we call _AEI edge handlers at boot.
> In some rare cases this causes problems. One example of this is the Minix
> Neo Z83-4 mini PC, this device has a clear DSDT bug where it has some copy
> and pasted code for dealing with Micro USB-B connector host/device role
> switching, while the mini PC does not even have a micro-USB connector.
> This code, which should not be there, messes with the DDC data pin from
> the HDMI connector (switching it to GPIO mode) breaking HDMI support.
> To avoid problems like this, this commit adds a new
> gpiolib_acpi.run_edge_events_on_boot kernel commandline option, which
> allows disabling the running of _AEI edge event handlers at boot.
> The default value is -1/auto which uses a DMI based blacklist, the initial
> version of this blacklist contains the Neo Z83-4 fixing the HDMI breakage.
> Cc:
> Cc: Daniel Drake <>
> Cc: Ian W MORRISON <>
> Reported-by: Ian W MORRISON <>
> Suggested-by: Ian W MORRISON <>
> Fixes: ca876c7483b6 ("gpiolib-acpi: make sure we trigger edge events at least once on boot")
> Signed-off-by: Hans de Goede <>
> ---
> Changes in v2:
> - Use a module_param instead of __setup
> - Do DMI check only once from a postcore_initcall

Patch applied for fixes, thanks for working this out,
sorry for slow reply.

Linus Walleij

      parent reply index

Thread overview: 7+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2019-08-27 20:28 Hans de Goede
2019-08-28 11:37 ` Mika Westerberg
2019-08-28 11:37 ` Andy Shevchenko
2019-08-28 12:20   ` Hans de Goede
2019-08-28 12:21     ` Hans de Goede
2019-08-28 13:16       ` Ian W MORRISON
2019-09-11  9:48 ` Linus Walleij [this message]

Reply instructions:

You may reply publically to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to='' \ \ \ \ \ \ \ \ \ \ \

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link

Linux-ACPI Archive on

Archives are clonable:
	git clone --mirror linux-acpi/git/0.git

	# If you have public-inbox 1.1+ installed, you may
	# initialize and index your mirror using the following commands:
	public-inbox-init -V2 linux-acpi linux-acpi/ \
	public-inbox-index linux-acpi

Newsgroup available over NNTP:

AGPL code for this site: git clone public-inbox