From: Lee Jones <lee@kernel.org>
To: Henning Schild <henning.schild@siemens.com>
Cc: Pavel Machek <pavel@ucw.cz>, Hans de Goede <hdegoede@redhat.com>,
Andy Shevchenko <andriy.shevchenko@linux.intel.com>,
linux-leds@vger.kernel.org, linux-kernel@vger.kernel.org
Subject: Re: [PATCH] leds: simatic-ipc-leds-gpio: do not run into endless EPROBE_DEFER loop
Date: Fri, 3 Feb 2023 07:59:46 +0000 [thread overview]
Message-ID: <Y9y+8nOU4yt/uPD5@google.com> (raw)
In-Reply-To: <20230202204730.7ee24c01@md1za8fc.ad001.siemens.net>
On Thu, 02 Feb 2023, Henning Schild wrote:
> Am Wed, 25 Jan 2023 19:17:11 +0100
> schrieb Henning Schild <henning.schild@siemens.com>:
>
> > Should the driver providing our GPIOs not be available we used to
> > return -EPORBE_DEFER out of the probe function and cause a
> > potentially endless loop that also printed a lot to the kernel log.
> >
> > ...
> > leds-gpio leds-gpio: cannot find GPIO chip igpio-f7188x-2, deferring
> > leds-gpio leds-gpio: Skipping unavailable LED gpio 0 (red:status-1)
> > ...
> >
> > The "leds-gpio" just ignores all entries and would never try again
> > even if the GPIOs show up later. But our extra two GPIOs could cause
> > that loop, in which we would even register/unregister "leds-gpio" and
> > cause all the printing.
> >
> > If any of those two extra GPIOs is not there, return with -ENODEV
> > instead of -EPROBE_DEFER.
>
> This is a really bad idea. The real fix for the future will be to
> write individual drivers which clearly describe their dep chains.
>
> This patch should not be merged.
Dropped.
--
Lee Jones [李琼斯]
prev parent reply other threads:[~2023-02-03 8:01 UTC|newest]
Thread overview: 4+ messages / expand[flat|nested] mbox.gz Atom feed top
2023-01-25 18:17 [PATCH] leds: simatic-ipc-leds-gpio: do not run into endless EPROBE_DEFER loop Henning Schild
2023-01-25 18:30 ` Henning Schild
2023-02-02 19:47 ` Henning Schild
2023-02-03 7:59 ` Lee Jones [this message]
Reply instructions:
You may reply publicly 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:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=Y9y+8nOU4yt/uPD5@google.com \
--to=lee@kernel.org \
--cc=andriy.shevchenko@linux.intel.com \
--cc=hdegoede@redhat.com \
--cc=henning.schild@siemens.com \
--cc=linux-kernel@vger.kernel.org \
--cc=linux-leds@vger.kernel.org \
--cc=pavel@ucw.cz \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.