From: Marek Vasut <marek.vasut@gmail.com>
To: Oliver Neukum <oliver@neukum.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>,
Dave Jones <davej@redhat.com>,
Linux Kernel <linux-kernel@vger.kernel.org>,
Larry Finger <Larry.Finger@lwfinger.net>,
Chaoming Li <chaoming_li@realsil.com.cn>,
"John W. Linville" <linville@tuxdriver.com>,
Matthew Garrett <mjg@redhat.com>,
"Greg Kroah-Hartman" <gregkh@suse.de>,
USB list <linux-usb@vger.kernel.org>,
Linux Wireless List <linux-wireless@vger.kernel.org>
Subject: Re: loading firmware while usermodehelper disabled.
Date: Sun, 1 Jan 2012 10:54:47 +0100 [thread overview]
Message-ID: <201201011054.47233.marek.vasut@gmail.com> (raw)
In-Reply-To: <201201011048.18953.oliver@neukum.org>
> Am Samstag, 31. Dezember 2011, 19:39:18 schrieb Marek Vasut:
> > maybe we should implement such thing into the firmware loader itself?
> > Allow it -- for example via some node in /dev -- to force loading
> > firmware into some buffer in kernel just before suspend so it'll
> > certainly be readily available at resume time?
>
> This is difficult. We don't know at suspend time which firmware we will
> need at resume time.
That's not actually true ... you can ask the drivers if they need to load
firmware after resume ... that can be implemented and udev can handle it. The
driver should know if the hardware it's controlling is stupid or not.
> We could keep a record of firmware we needed
> to get to the state we are, but this is a very complex scheme.
Not really. You might have a device where you load firmware, issue suspend
command and then issue resume command, while the device will still retain
firmware in it, it'll be only in low power mode throughout the sleep cycle.
Then you can have a device that will just power down completely, wiping the
firmware from it's memory. And that's what should be taken care of by injecting
the firmware before suspend. The driver should be able to tell you if the device
is broken and needs this special treatment.
This will though delay the time to suspect slightly, but that can be considered
a price you have to pay if your hardware is stupid.
M
>
> Regards
> Oliver
next prev parent reply other threads:[~2012-01-01 9:54 UTC|newest]
Thread overview: 91+ messages / expand[flat|nested] mbox.gz Atom feed top
[not found] <20111230235421.GA6054@redhat.com>
2011-12-31 0:22 ` loading firmware while usermodehelper disabled Linus Torvalds
2011-12-31 0:40 ` Matthew Garrett
2011-12-31 15:33 ` Alan Stern
2011-12-31 15:59 ` Oliver Neukum
2012-01-01 2:21 ` Alan Stern
2012-01-01 12:22 ` Oliver Neukum
2012-01-01 16:17 ` Alan Stern
2012-01-01 16:25 ` Michael Büsch
2012-01-01 20:30 ` Linus Torvalds
2012-01-01 21:27 ` Oliver Neukum
2012-01-01 21:39 ` Michael Büsch
2012-01-02 3:33 ` Matthew Garrett
2012-01-02 7:56 ` Oliver Neukum
2012-01-02 4:17 ` Marek Vasut
2012-01-02 5:35 ` Gábor Stefanik
2012-01-02 8:38 ` Marek Vasut
2012-01-02 16:54 ` Alan Stern
2012-01-02 20:41 ` Jack Stone
2012-01-02 20:48 ` Linus Torvalds
2012-01-02 20:55 ` Jack Stone
2012-01-02 21:00 ` Linus Torvalds
2012-01-02 21:09 ` Jack Stone
2012-01-02 21:23 ` Linus Torvalds
2012-01-02 21:31 ` Jack Stone
2012-01-02 21:52 ` Marek Vasut
2012-01-02 21:57 ` Jack Stone
2012-01-02 22:31 ` Marek Vasut
2012-01-02 23:25 ` Jack Stone
2012-01-03 0:31 ` Marek Vasut
2012-01-03 0:44 ` Jack Stone
2012-01-03 0:58 ` Alan Cox
2012-01-03 7:17 ` Marek Vasut
2012-01-03 7:41 ` Oliver Neukum
2012-01-03 0:35 ` Alan Cox
2012-01-03 0:50 ` Alan Cox
2012-01-02 21:19 ` Matthew Garrett
2012-01-02 21:26 ` Jack Stone
2012-01-03 0:42 ` Alan Cox
2012-01-03 11:57 ` Oliver Neukum
2012-01-03 12:19 ` Jack Stone
2012-01-03 13:20 ` Alan Cox
2012-01-03 13:30 ` Oliver Neukum
2012-01-03 13:36 ` Alan Cox
2012-01-02 21:27 ` Linus Torvalds
2012-01-02 21:50 ` Matthew Garrett
2012-01-02 22:03 ` Linus Torvalds
2012-01-02 22:12 ` Matthew Garrett
2012-01-02 22:19 ` Linus Torvalds
2012-01-02 22:29 ` Matthew Garrett
2012-01-02 22:46 ` Linus Torvalds
2012-01-02 23:00 ` Matthew Garrett
2012-01-02 23:31 ` Jack Stone
2012-01-03 0:13 ` Matthew Garrett
2012-01-03 0:20 ` Alan Cox
2012-01-03 0:37 ` Matthew Garrett
2012-01-03 0:22 ` Jack Stone
2012-01-03 0:31 ` Alan Cox
2012-01-03 0:41 ` Jack Stone
2012-01-03 0:38 ` Matthew Garrett
2012-01-03 0:47 ` Alan Cox
2012-01-03 0:18 ` Alan Cox
2012-01-03 8:26 ` Ingo Molnar
2012-01-03 2:45 ` Alan Stern
2012-01-03 3:25 ` Matthew Garrett
2012-01-03 5:53 ` Linus Torvalds
2012-01-03 11:50 ` Oliver Neukum
2012-01-03 15:16 ` Alan Stern
2012-01-03 12:24 ` Matthew Garrett
2012-01-03 16:29 ` Linus Torvalds
2012-01-03 15:09 ` Alan Stern
2012-01-03 9:16 ` Alexander E. Patrakov
2012-01-03 9:24 ` david
2012-01-03 13:43 ` Alan Cox
2012-01-03 14:12 ` Bernd Petrovitsch
2012-01-03 0:00 ` Alan Cox
2012-01-02 23:50 ` Alan Cox
2012-01-02 23:53 ` Alan Cox
2011-12-31 16:27 ` Matthew Garrett
2011-12-31 14:20 ` Martin Schleier
2011-12-31 18:39 ` Marek Vasut
2012-01-01 9:48 ` Oliver Neukum
2012-01-01 9:54 ` Marek Vasut [this message]
2012-01-01 12:28 ` Oliver Neukum
2012-01-01 16:32 ` Marek Vasut
2012-01-01 17:06 ` Marek Vasut
2012-01-01 20:39 ` Alan Cox
2012-01-01 20:50 ` Michael Büsch
2012-01-02 3:24 ` Marek Vasut
2012-01-02 3:29 ` Marek Vasut
2012-01-01 3:49 ` Larry Finger
2012-01-01 22:45 ` Jack Stone
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=201201011054.47233.marek.vasut@gmail.com \
--to=marek.vasut@gmail.com \
--cc=Larry.Finger@lwfinger.net \
--cc=chaoming_li@realsil.com.cn \
--cc=davej@redhat.com \
--cc=gregkh@suse.de \
--cc=linux-kernel@vger.kernel.org \
--cc=linux-usb@vger.kernel.org \
--cc=linux-wireless@vger.kernel.org \
--cc=linville@tuxdriver.com \
--cc=mjg@redhat.com \
--cc=oliver@neukum.org \
--cc=torvalds@linux-foundation.org \
/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 a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).