More on hotplug issue w/HAL

[Otto Solares]

On Thu, Jan 08, 2004 at 06:08:48PM -0700, Matthew Mastracci wrote:
> On Thu, 2004-01-08 at 16:31, David Zeuthen wrote:
> > On Thu, 2004-01-08 at 02:37, Matthew Mastracci wrote:
> > > > Disregarding media detection for a while, does all your devices show up
> > > > with the latest CVS version?
> > > 
> > > Works perfectly.  Tested startup and hotplug.  My card reader appears as
> > > a multi-LUN SCSI device w/multiple SCSI interfaces, as expected.  See
> > > attached screenshot for gorgeous details.  ;)
> > > 
> > 
> > Rock. I suppose media detection doesn't work yet, no?
> 
> Not yet - where might I find the code to do this?  To be more specific,
> it *does* work on hotplug or initial scan - it's just when the media
> itself is removed or inserted (versus removing or inserting the CF
> reader itself on the USB bus), nothing changes in HAL.
> 
> I've been playing around with SCSI device detection.  The easiest way to
> do it seems to be just open()ing the root block device (note that
> open()ing the partitions may still succeed if the media was removed
> without umount-ing).  If you've got floppy code working, you're probably
> already doing this.
> 
> BTW - I've noticed that the floppy drive doesn't appear anywhere within
> sysfs.  I'm guessing that this is a kernel issue - there doesn't seem to
> be a device class for it at all!  

Same for AT / PS/2 keyboards, serials, parallel, PS/2 mice.

> This brings me to a different point - should there be a few virtual
> device nodes *above* the current devices in HAL today?  The current HAL
> architecture is very PCI-centric.  I would imagine tree below to be the
> ideal:

I think we should provide a way to legacy devices show in the gdl.  World
is still full of legacy devices.

> + Non-System Items
>    + ???  Are there any ???
> + System Devices
>    + Legacy Serial Ports
>       + Serial Port
>       + Serial Port
>    + Legacy Parallel Ports
>       + Parallel Port
>       + Parallel Port
>    + Floppy Drive Controller
>       + Floppy Drive
>    + I2C Bus
>       + Some monitoring device
>    + PCI Bus
>       + On-board PCI Device 1
>       + On-board PCI Device 2
>       + On-board PCI Device 3
>       + AGP Bridge
>           + Superfast Video Card
>       + External PCI Bridge
>           + PCI Card 1
>           + PCI Card 2
>           + PCI Card 3
> 
> Unfortunately, it looks like there are a few device classes that are
> missing bus entries in sysfs (ie: missing kernel support).  For example,
> none of the legacy floppy/serial/parallel ports appear in there.  I
> suppose that someone just needs to do the grunt work of writing the
> sysfs classes.  :)

Exactly.  That should be handled by ISA bus kernel code, problem is that
legacy isa device drivers doesn't need registering with a dumb bus, but
in reallity it needs fixing in the kernel side.  I always though that
any kind of bus layer needs device registering, probably isa is the exception.

-solca