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    SubjectRe: modules.pnpmap output support
    On Fri, Nov 21, 2003 at 12:44:45PM +0100, Takashi Iwai wrote:
    > At Thu, 20 Nov 2003 21:23:20 +0000,
    > Adam Belay wrote:

    --> snip

    > > The device ID is checked, but this checking occurs during the driver's
    > > probe function, when it calls pnp_request_card_device. This is needed
    > > in order for us to properly deal with multidevice cards, especially in
    > > ALSA.
    >
    > well, the probe callback of all ALSA isapnp drivers doesn't look for
    > the matching device ids. that is, the callback trusts that the pnp
    > core passes the correct pnp_card_device_id, and it checks only the
    > devices listed on this id. so, as mentioned above, if there are
    > multiple entries with the same card id but different device ids,
    > probing the second entry will fail, because match_card() returns the
    > first matching id.

    Hmm, I agree, if there are multiple entries with the same card ID then
    only the first ID would be matched. I could add some code to match_card()
    so that it checks to see if all of the devices in the list are present.
    This would, however, break ALSA's current policy of enabling a card, even
    if some of its device components are unavailabe. Could you provide any
    specific examples of multiple entries with the same card ID? I'd like to
    look at some closer.

    >
    > > If possibly, I'd like to see the devices in these cards be
    > > handled individually in 2.7 but note that doing so would require
    > > changes to some drivers and subsystems. The current system works well
    > > for 2.6.
    > >
    > > Because of these factors, and the fact that pnp_device_id is also used,
    > > I think that we have to include all of the IDs in the pnpidmap. This
    > > would include both the card id and the individual device IDs on each
    > > card. pnp_device_id can use the isapnp card device ids in addition to
    > > the ids reported by the pnpbios.
    >
    > oh, can pnp_device_id be a card id, too, not only a device id?

    Only a device ID, but those device IDs can reside on isapnp cards.

    >
    >
    > Takashi


    Thanks,
    Adam
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