Re: driverfs is not for everything! (was: [PATCH] /proc/scsi/map)

David Brownell
2002-06-24T01:34:22Z

> Is the device PHYSICALLY hooked up to the computer? If not, it shouldn't be
> in devicefs.

What's "devicefs" -- some new filesystem? Or a mis/re-naming of "driverfs"?
I assume you don't mean "devfs".

> The device tree (for which devicefs is the fs representation) was originally
> meant to enable good device power management and configuration.

Surely a driver using IP-over-wire like iSCSI is no less deserving of appearing
in "driverfs" than one whose driver uses custom-protocol-over-a-"wire" like USB,
FireWire, FC, IR, SCSI, or Bluetooth? I don't see why some disks (for example)
should deserve to be "more equal than others" -- and approved to be in driverfs.

Admittedly some of those may have few power management concerns beyond basic
startup/shutdown sequencing. But the configuration management issues won't
go away just because a driver talks to a device over some more generalized
notion of wire. I suspect those are probably more important, long-term, than
the power management hooks. I seem to recall other operating systems starting
out with a device/driver tree well before power management existed, and was
surprised when I noticed Linux didn't have one yet.

No, of course driverfs isn't for everything. But if it's not for all drivers,
then what's it for -- just power management?

- Dave