I do have a Toshiba laptop (L750) and the problem happens to me also.
I can try to help you solving the DSDT problem looking how to include the wake code onto the dsdt device, but i need to use the same driver as you , so both of us use the same items.
Can you share your driver?
Here is the PXHCD.kext and i am using it in Extra\Extenion folder
why does it show ARPT on a bunch of places ?? have u been playing with dsdt and ar9287 fix ?
it has come default with original extracted DSDT with linux live CD.
i have added just the device names under APRTs.
i have checked with IOregisrtyexporer that what IRQs HPET i using and added those 4 IRQs in my DSDT.
i have not applied any DSDT fixes except addition of followings:
1. Device details in RP1, RP-2, RP-3, RP-4,
2. introduced ATI 6770m code under PEGP and audio in HDEF to get it detected
3. Rest all minor fixes like sleep, function keys, etc.
i am attaching my freshly extracted DSDT for your reference.
My BIOS is HP Insyde and i am using F.14 version.
I would like to share in details about my USB issues:
1. USB2 on 0x1d is working OK. Any device plugged is detected normally.
Sometimes i have to replug the usb device in this port after WAKE as they are not detected if they remain plugged before sleep.
(Occurrence i very rare)
2. USB2 on 0x1a is not working i guess. not sure.
this is an internal usb. Validity fingerprint sensor and HP truevision HD webcam connected to it.
The HP truevision HD webcam is also not working.(Tried using anyisightcam.kext+ cameracontrol; didnt work in Lion-10.7.3)
3.USB 3.0 on RP04, problem as explained works after WAKE only.
may be this can help you guys.