AHCI suspend/resume support --take4

Hi, all

This is resend of the take 4 of AHCI suspend/resume patches. The patch is against libata #upstream.

Compared with last version, all the changes are in [PATCH 6/6]. In particular, I made changes to the sixth patch to integrate it with Tejun's PM patch.

Thanks,
Forrest

My current, still-pending request for these patches:

Please split up the patches such that each individual patch -- when applied in succession, creates a compilable, usable driver. Patch #1 must producing a working driver. Patches #1-2 must produce a working driver. Patches #1-3 must produce a working driver. Patches #2-3 (without patch #1) need not apply, much less produce a working driver.

As I described in an earlier email, patches are like mathematical proofs: each step must produce a "complete equation."

For example, patch #1 in this series looks OK -- if only the existing users of ahci_stop_engine() and ahci_start_engine() to work.

As another example, the ACPI patches need to be split up into logical chunks, probably just two patches:

1) Add support necessary to utilize _SDD, _GTF (SATA)
2) Add support necessary to utilize _GTM, _STM (PATA)

or perhaps three patches:

1) _GTF support, basic ACPI support
2) SATA support (_SDD, other SATA details)
3) PATA support (_GTM, _STM, other PATA details)

Overall, your code changes are looking good, but are not split up in a usable manner.

Regards,

Jeff