When detaching device trees parent devices must be detached prior to
detaching its children. This is because parent devices can have
pointers to the child devices in their softcs which are not
invalidated by device_delete_child(). This can cause use after free
issues and panic().
Device drivers implementing trees, must ensure its detach function
detaches or deletes all its children before returning.
While at it remove now redundant device_detach() calls before
device_delete_child() and device_delete_children(), mostly in
the USB controller drivers.
Tested by: Jan Henrik Sylvester <me@janh.de>
Reviewed by: jhb
Differential Revision: https://reviews.freebsd.org/D8070
MFC after: 2 weeks
USB support
This revision adds USB (EHCI/OHCI/OTG, depending on SoC type) support for
various Ralink/Mediatek SoCs.
Currently USB is not supported on MT7621, this will be a future addition.
A USB PHY driver is also included, so that we can properly initialize the
USB PHY (e.g., clocks, resets, registers where needed), before attempting
to initialize EHCI/OHCI/OTG functionality.
Approved by: adrian (mentor)
Sponsored by: Smartcom - Bulgaria AD
Differential Revision: https://reviews.freebsd.org/D5841
