????: Help:why bus resource shortage?

Søren Schmidt sos at freebsd.org
Fri Jun 30 09:30:17 UTC 2006

   John-Mark Gurney wrote:

Gerald Heinig wrote this message on Fri, Jun 30, 2006 at 10:41 +0200:

On Fri, 2006-06-30 at 01:16 -0700, John-Mark Gurney wrote:

This has now been fixed by making the built in driver return a negative
value for the probe.. so your probe routine can return 0, and it will
win the probe for the device...

Minor nitpick: it may perhaps be better to return a smaller negative
value (eg. -5) rather than 0. IIRC -10 is the default score used by
standard system drivers and 0 is the highest score available. If someone
wants to use an alternative driver to Hong's and the standard system's
it won't attach.

The correct values to return are:
#define BUS_PROBE_SPECIFIC      0       /* Only I can use this device */
#define BUS_PROBE_VENDOR        (-10)   /* Vendor supplied driver */
#define BUS_PROBE_DEFAULT       (-20)   /* Base OS default driver */
#define BUS_PROBE_LOW_PRIORITY  (-40)   /* Older, less desirable drivers */
#define BUS_PROBE_GENERIC       (-100)  /* generic driver for dev */
#define BUS_PROBE_HOOVER        (-500)  /* Generic dev for all devs on bus */

So, ata should be returning _GENERIC, and Hong's driver should use

   Actually I have a local patch that makes ATA return BUS_PROBE_DEFAULT
   in case it has a "real" driver for the chip, and BUS_PROBE_GENERIC in
   case it takes it as a generic (legacy) ATA chip.
   That way I can do modules for new support without having to touch

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