[Fwd: Re: USB Key light on/off state depending on mount]

[Casey Dahlin]

I recently posted on lkml asking about making the light on your USB key 
shut off when it was not mounted. Some responses came back suggesting 
this is not difficult. Might we consider this for inclusion in Fedora?

-Casey Dahlin

-------- Original Message --------
Subject: 	Re: USB Key light on/off state depending on mount
Date: 	Sat, 25 Aug 2007 13:58:06 +0200
From: 	Éric Piel <Eric.Piel(a)tremplin-utc.net&gt;
To: 	James Bruce <bruce(a)andrew.cmu.edu&gt;
CC: 	linux-kernel(a)vger.kernel.org, Casey Dahlin <cjdahlin(a)ncsu.edu&gt;
References: 	<fa.BwCgwGvTNIOD+KEeBrvP11xCEmw(a)ifi.uio.no&gt; 
<46CF6791.8040509(a)shaw.ca&gt; <46D00928.1080901(a)andrew.cmu.edu&gt;



25/08/07 12:49, James Bruce wrote/a écrit:
>  Robert Hancock wrote:
> > Casey Dahlin wrote:
> >> Most USB keys nowadays have a small LED somewhere inside of them that 
> >> lights up when they are plugged in. On a windows box, the key is lit 
> >> up whenever it is mounted, and as soon as it is unmounted it turns 
> >> off, giving a handy physical indicator that the key is safe to 
> >> remove. On linux, the light is simply on whenever the key is plugged in.
> >>
> >> Should linux toggle the light depending on mount state? Is it as 
> >> trivial as it seems or does this reflect some larger issue?
> >
> > I think that Windows turns off power to the port when you do the 
> > "safely remove hardware" on it, or something like that. Mount/unmount 
> > doesn't really indicate whether the device is in use in Linux, though, 
> > since it can still be potentially accessed even when the device isn't 
> > mounted.
>  
>  If there is a way to toggle the power state from userspace, then a 
>  desktop environment or userland tool can emulate the Windows behavior if 
>  that is desired.  A lot of devices can charge via USB now, and this is 
>  actually more convenient on Linux than on Windows (in effect Windows 
>  requires drivers in order to charge something).  However, having direct 
>  control over this is useful. 
Yes, maybe some userspace such as HAL could turn off
the usb devices at 
the same time it's unmounted. Actually that would be rather intuitive 
way to tell the user the umount is finished. There doesn't seem to be 
any loss of funcitonality, once it's turned off you can still re-access 
the device, and it's automatically turned on again (at least on my PC).

For the record, here is how one can switch off a usb device (as root):
# cd /sys/bus/usb/devices/usb*/[0-9]-[0-9] (just go to the directory of 
the device)
# echo -n 2 > *:1.0/power/state
# echo -n 2 > power/state

I use this to turn off my optical mouse when watching movies, but it 
works fine as well to turn off usb storage devices.
It can also be turned on with
# echo -n 0 > power/state

See you,
Eric
-
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[Hans de Goede]

Casey Dahlin wrote:
>  I recently posted on lkml asking about making the light on your USB
> key 
>  shut off when it was not mounted. Some responses came back suggesting 
>  this is not difficult. Might we consider this for inclusion in Fedora?
>  
>  -Casey Dahlin
>   
This sounds like a great plan, I had a friend of mine complain about the drive 
light not going off after unmount yesterday.

Is anyone already working on a patch? If not I can take a shot, be warned 
though, I'm not familiar with hal's internals.

Regards,

Hans


>  -------- Original Message --------
>  Subject:     Re: USB Key light on/off state depending on mount
>  Date:     Sat, 25 Aug 2007 13:58:06 +0200
>  From:     Éric Piel <Eric.Piel(a)tremplin-utc.net&gt;
>  To:     James Bruce <bruce(a)andrew.cmu.edu&gt;
>  CC:     linux-kernel(a)vger.kernel.org, Casey Dahlin <cjdahlin(a)ncsu.edu&gt;
>  References:     <fa.BwCgwGvTNIOD+KEeBrvP11xCEmw(a)ifi.uio.no&gt; 
>  <46CF6791.8040509(a)shaw.ca&gt; <46D00928.1080901(a)andrew.cmu.edu&gt;
>  
>  
>  
>  25/08/07 12:49, James Bruce wrote/a écrit:
> > Robert Hancock wrote:
> >> Casey Dahlin wrote:
> >>> Most USB keys nowadays have a small LED somewhere inside of them 
> >>> that lights up when they are plugged in. On a windows box, the key 
> >>> is lit up whenever it is mounted, and as soon as it is unmounted it 
> >>> turns off, giving a handy physical indicator that the key is safe to 
> >>> remove. On linux, the light is simply on whenever the key is plugged 
> >>> in.
> >>>
> >>> Should linux toggle the light depending on mount state? Is it as 
> >>> trivial as it seems or does this reflect some larger issue?
> >>
> >> I think that Windows turns off power to the port when you do the 
> >> "safely remove hardware" on it, or something like that. Mount/unmount 
> >> doesn't really indicate whether the device is in use in Linux, 
> >> though, since it can still be potentially accessed even when the 
> >> device isn't mounted.
> >
> > If there is a way to toggle the power state from userspace, then a 
> > desktop environment or userland tool can emulate the Windows behavior 
> > if that is desired.  A lot of devices can charge via USB now, and this 
> > is actually more convenient on Linux than on Windows (in effect 
> > Windows requires drivers in order to charge something).  However, 
> > having direct control over this is useful.
>  Yes, maybe some userspace such as HAL could turn off the usb devices at 
>  the same time it's unmounted. Actually that would be rather intuitive 
>  way to tell the user the umount is finished. There doesn't seem to be 
>  any loss of funcitonality, once it's turned off you can still re-access 
>  the device, and it's automatically turned on again (at least on my PC).
>  
>  For the record, here is how one can switch off a usb device (as root):
>  # cd /sys/bus/usb/devices/usb*/[0-9]-[0-9] (just go to the directory of 
>  the device)
>  # echo -n 2 > *:1.0/power/state
>  # echo -n 2 > power/state
>  
>  I use this to turn off my optical mouse when watching movies, but it 
>  works fine as well to turn off usb storage devices.
>  It can also be turned on with
>  # echo -n 0 > power/state
>  
>  See you,
>  Eric
>  -
>  To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
>  the body of a message to majordomo(a)vger.kernel.org
>  More majordomo info at  http://vger.kernel.org/majordomo-info.html
>  Please read the FAQ at  http://www.tux.org/lkml/
>

MCP55 built in ethernet + forcedeth driver cannot get dhcp leace

[Casey Dahlin]

I have 2 kernels on a box: 2.6.21-1.3194.fc7 and 2.6.22.4-65.fc7 . I 
cannot acquire a DHCP lease when booted into the latter.

No error messages anywhere, and the problem persists on a 2.6.21 kernel 
built from Linus' git tree.