mirror of https://lore.kernel.org/lkml/
 help / color / mirror / Atom feed
From: mark gross <markgross@thegnar.org>
To: Alan Cox <alan@lxorguk.ukuu.org.uk>
Cc: markgross@thegnar.org, linux-kernel@vger.kernel.org,
	John Stultz <john.stultz@linaro.org>,
	"Rafael J. Wysocki" <rjw@sisk.pl>,
	arve@android.com, Alan Stern <stern@rowland.harvard.edu>,
	amit.kucheria@linaro.org, farrowg@sg.ibm.com,
	"Dmitry Fink (Palm GBU)" <Dmitry.Fink@palm.com>,
	linux-pm@lists.linux-foundation.org, khilman@ti.com,
	Magnus Damm <damm@opensource.se>,
	mjg@redhat.com, peterz@infradead.org
Subject: Re: [markgross@thengar.org: Re: [RFC] wake up notifications and suspend blocking (aka more wakelock stuff)]
Date: Mon, 3 Oct 2011 17:35:49 -0700	[thread overview]
Message-ID: <20111004003549.GA26888@mgross-G62> (raw)
In-Reply-To: <20111003093226.2b5e9c4d@lxorguk.ukuu.org.uk>

On Mon, Oct 03, 2011 at 09:32:26AM +0100, Alan Cox wrote:
> On Sun, 2 Oct 2011 09:48:49 -0700
> mark gross <markgross@thegnar.org> wrote:
> 
> > Forwarding to bigger group for discussion.
> 
> Looks clean enough - only question I have is do we need a separate
> 'suspend block' or can latency do it -suspend is a very very high latency
> event. I guess the suspend block is clearer in intent than abusing latency
> but I do wonder if the actual suspend path should also check latency
> constraints too. If I've asked for 5mS latency then suspend is a wrong
> choice!
> 
I don't think over loading the meaning of cpu_dma_latency would work
well for this.  If cpu_dma_latency constraint is > 5mS then EFAIL a
suspend attempt?  feels clunky.

If you use less than then anyone using a constraint (like some wifi
and audio) would block suspend.  also not so good.  


The poster child for needing this is the USB gadget device with
associated charging over USB.  Here we can't sleep because we'd have a
hard time meeting USB spec if we did.  Also, we don't want to sleep
while charging if charging is under OS control.  (checking temperature
is tricky while suspended.)

--mark


  reply	other threads:[~2011-10-04  0:35 UTC|newest]

Thread overview: 4+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2011-10-02 16:48 mark gross
2011-10-03  8:32 ` Alan Cox
2011-10-04  0:35   ` mark gross [this message]
  -- strict thread matches above, loose matches on Subject: below --
2011-10-02 16:47 mark gross

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=20111004003549.GA26888@mgross-G62 \
    --to=markgross@thegnar.org \
    --cc=Dmitry.Fink@palm.com \
    --cc=alan@lxorguk.ukuu.org.uk \
    --cc=amit.kucheria@linaro.org \
    --cc=arve@android.com \
    --cc=damm@opensource.se \
    --cc=farrowg@sg.ibm.com \
    --cc=john.stultz@linaro.org \
    --cc=khilman@ti.com \
    --cc=linux-kernel@vger.kernel.org \
    --cc=linux-pm@lists.linux-foundation.org \
    --cc=mjg@redhat.com \
    --cc=peterz@infradead.org \
    --cc=rjw@sisk.pl \
    --cc=stern@rowland.harvard.edu \
    /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

all inboxes | Powered by JetHome®