ACPI device without physical node (pnpacpi oddity?)

[Andy Lutomirski <luto@xxxxxxxxxxxxxx>]

I have this device:

        Device (HIDD)
        {
            Name (_HID, "INT33D5")  // _HID: Hardware ID
            Name (_CID, "PNP0C02" /* PNP Motherboard Resources */)  //
_CID: Compatible ID
            Name (HBSY, Zero)
            Name (HIDX, Zero)
            Name (HMDE, Zero)
            Name (HRDY, Zero)
            Method (_STA, 0, Serialized)  // _STA: Status
            {
                If ((OIDE () < One))
                {
                    Return (Zero)
                }

                Return (0x0F)
            }

            Method (HDDM, 0, Serialized)
            {
                Name (DPKG, Package (0x04)
                {
                    0x11111111,
                    0x22222222,
                    0x33333333,
                    0x44444444
                })
                Return (DPKG) /* \_SB_.HIDD.HDDM.DPKG */
            }

            Method (HDEM, 0, Serialized)
            {
                HBSY = Zero
                If ((HMDE == Zero))
                {
                    Return (HIDX) /* \_SB_.HIDD.HIDX */
                }

                Return (HMDE) /* \_SB_.HIDD.HMDE */
            }

            Method (HDMM, 0, Serialized)
            {
                Return (HMDE) /* \_SB_.HIDD.HMDE */
            }

            Method (HDSM, 1, Serialized)
            {
                HRDY = Arg0
            }

            Method (HPEM, 1, Serialized)
            {
                HBSY = One
                If ((HMDE == Zero))
                {
                    HIDX = Arg0
                }
                Else
                {
                    HIDX = Arg0
                }

                Notify (HIDD, 0xC0) // Hardware-Specific
                Local0 = Zero
                While (((Local0 < 0xFA) && HBSY))
                {
                    Sleep (0x04)
                    Local0++
                }

                If ((HBSY == One))
                {
                    HBSY = Zero
                    HIDX = Zero
                    Return (One)
                }
                Else
                {
                    Return (Zero)
                }
            }

            Method (NRBT, 2, NotSerialized)
            {
                If ((OIDE () >= One))
                {
                    If ((HRDY == One))
                    {
                        HIDX = 0x08
                        Notify (HIDD, 0xC0) // Hardware-Specific
                    }
                }
            }
        }

_STA returns 0x0f, and the device is functional if I attach to it
directly.  But I want to write a proper driver for it and to attach to
the correct device, and the ACPI and PnP bus code isn't cooperating.

>From inspection of the code, acpi_pnp.c determines that the device is
a pnp device because pnp0c02 is in acpi_pnp_device_ids.  This causes
the device to have a concrete handler, so no platform device is
created.  However, pnpacpi/core.c rejects it because it has no _CRS
method.  As a result, it's in limbo.

What's the right thing to do here?  I could modify acpi_pnp.c to
reject the device, which will let the generic platform fallback claim
it.  I could modify pnpacpi to accept the device despite the lack of
_CRS, so a pnp device will be created.  I could bind directly as an
ACPI driver (somewhat suboptimal because apparently that's frowned
upon).  I could also write *both* an ACPI driver and platform driver
and call acpi_create_platform_device from the ACPI driver, but that
seems a bit ugly.

Thoughts?

--Andy


-- 
Andy Lutomirski
AMA Capital Management, LLC
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