---
- branch: MAIN
  date: Sun May 23 11:49:45 UTC 2021
  files:
  - new: '1.139'
    old: '1.138'
    path: src/sys/dev/usb/xhci.c
    pathrev: src/sys/dev/usb/xhci.c@1.139
    type: modified
  - new: '1.19'
    old: '1.18'
    path: src/sys/dev/usb/xhcireg.h
    pathrev: src/sys/dev/usb/xhcireg.h@1.19
    type: modified
  - new: '1.18'
    old: '1.17'
    path: src/sys/dev/usb/xhcivar.h
    pathrev: src/sys/dev/usb/xhcivar.h@1.18
    type: modified
  id: 20210523T114945Z.17494643da4beb4d4ce01ceafebab05096712388
  log: |
    xhci(4): Draft suspend/resume.

    Work almost entirely done and tested by maya@ based on xhci 1.2 spec;
    tidied up and tweaked by me.

    Not sure about issuing Stop Endpoint commands or ensuring the Command
    Ring is in the Stopped or Idle state, but this seems to work as is,
    so it's already an improvement over what we had before which was no
    xhci suspend/resume at all.

    In particular, it's not clear to us:

    - if we don't have any pending USB activity whether we need to issue
      the Stop Endpoints or quiesce the command ring; but

    - if we do have any pending USB activity whether issuing Stop
      Endpoint is enough or whether we also need to do anything to
      synchronize with other software logic to quiesce it too.
  module: src
  subject: 'CVS commit: src/sys/dev/usb'
  unixtime: '1621770585'
  user: riastradh