Re: Udev rule for HSDPA modem

[Greg KH <greg@kroah.com>]

On Sun, Nov 30, 2008 at 06:21:11AM +0100, Kay Sievers wrote:
> On Sat, Nov 29, 2008 at 18:37, Greg KH <greg@kroah.com> wrote:
> > On Sat, Nov 29, 2008 at 10:00:59AM +0200, Jar wrote:
> >> Greg KH wrote:
> >>> HAL contains a list of these modems and a mapping of each port to what
> >>> it does based on the specific device.
> >>> Try using that instead of udev specific rules for your accessed to the
> >>> modem, it will work much better.
> >>
> >> Thanks for your reply! Does HAL require that I have desktop installed, this
> >> is my home "server" machine without X? Do you have any starting point or
> >> where to learn more how to do this with HAL.
> >
> > I do not think HAL requires X.  Try asking on your distro mailing list
> > for how they have incorporated HAL into the releases you are using.
> 
> It might get pretty complicated to use D-Bus/HAL for simple setups,
> and rather static configurations like this. NetworkManager handles
> that, and we will even get modem-probing soon, but in cases like this
> it might be easier to have a simple - not very flexible - but working
> solution.
> 
> Maybe we can have an "index" sysfs file at the serial device, which
> carries the instance number, per usb device? This would allow us to
> create persistent links which do not depend on the kernel device
> enumeration across multiple device.
> 
> We did the same for v4l devices recently:
>   http://git.kernel.org/?p=linux/kernel/git/torvalds/linux-2.6.git;a=commit;hS9a7555b31e65e66fb84c881d07d2bf18c974d0
> 
> Greg, what do you think?

Don't we already have something like this today (the "ports" on an
individual usb-serial device)?  Or do we just need to export that a bit
better?

I have no objection to something like this if it would help out.  But I
think the bigger problem is that userspace doesn't always "know" which
port does what for which type of device.  That is something that we have
talked about adding as a sysfs attribute a while ago, but it never went
very far as no one had a patch :(

thanks,

greg k-h