No ethernet interface found after suspend-resume

Sriram V vshrirama at gmail.com
Fri Apr 30 12:24:20 EDT 2010


On Fri, Apr 30, 2010 at 9:40 PM, Chris Ball <cjb at laptop.org> wrote:
> Hi,
>
>   > How can i reset the card? I use a gpio - If i do a reset - The
>   > firmware again gets downloaded. I need to again configure my
>   > ethernet interface and get an IP address. which i dont think is
>   > the right way to do.
>
> Yes, that's what has to happen if the card loses power.  (And the card
> losing power is what has to happen on vanilla 2.6.29.)
>
>   > Can you elaborate on this? I cant upgrade to .33. I would like to
>   > back port to .29.
>
> Let me just check what you're trying to do -- you want the card to
> retain power while the CPU's in suspend, and you want it to stay
> associated during suspend.  Do you also want packets sent to the card
> during suspend to wake up the system?

I think the connection should stay associated after comming back from
suspend-resume. Becaue that was the state before going to suspend.

I dont want the system to be woken up during suspend - i can live without it.


 Or is it just the extra time
> that it takes to bring the interface back up after suspend that you're
> trying to get rid of?


Do all - have to bring the interface backup after
suspend-resume. Is this taken care by the user-space. But how does the
user space know that the interface is back up and query for an IP everytime
the device comes back from suspend and associate with an AP.

Is this normal behaviour elsewhere?

Not really sure this the default behaviour.

Besides, My device is externally powered and i just specify the ocr's
ranges to the mmc drivers.
So probably the state machine within libertas does not expect CMD5,
CMD8 and so on....

Thank you, i will look at the patches.

>
> Here's some of the patchset I was talking about:
>
> http://git.kernel.org/?p=linux/kernel/git/torvalds/linux-2.6.git;a=commit;h=da68c4eb258cd9f3f0b8aeb7e46b8118bb6358b6
> http://git.kernel.org/?p=linux/kernel/git/torvalds/linux-2.6.git;a=commit;h=2f4cbb3d834922ffa0309b6a08fa42dac87ef9d2
> http://git.kernel.org/?p=linux/kernel/git/torvalds/linux-2.6.git;a=commit;h=3bca4cf703826fcb2bbabbe19c6fc7b2fc4fd7cc
> http://git.kernel.org/?p=linux/kernel/git/torvalds/linux-2.6.git;a=commit;h=40216842dca4fa485cb1aa5eb231149a4a57cc85
> http://git.kernel.org/?p=linux/kernel/git/torvalds/linux-2.6.git;a=commit;h=6b5eda369ac3772dad416ef96d86064204d74770
>
> The commits themselves try to document what's going on -- Nico's
> patchset introduces an MMC_PM_KEEP_POWER flag to be set per-card,
> and then allows cards with that flag set to avoid the standard
> reinitialization on resume.  We use this at OLPC to allow the 8686
> to wake up the host on new packets, by keeping the interface up and
> sending the HOSTSLEEP command to the module in if_sdio_suspend().
>
> - Chris.
> --
> Chris Ball   <cjb at laptop.org>
> One Laptop Per Child
>



More information about the libertas-dev mailing list