Resume from suspend on Toshiba Sat Pro 4600 oddity

[Gary E. RAFE, Ph.D.]

I just installed 5.4-R in an open partition
on my wife's Toshiba Satellite Pro 4600,
which has been running 4.11-R without complaint.

The installation went smoothly, and everything that
worked in 4.11-R appears to work in 5.4-R.

Even ACPI suspend/resume (acpiconf -s 3) worked mostly,
which I found encouraging, since it hasn't on my
Toshiba Satellite Pro 6100 running 5.4-R.

The first "resume" problem I've seen before:
the USB system fails to come back from the suspend,
which happens on my 6100, also.
This is "easy" to fix by adding USB_DEBUG to the kernel.

The other nit I haven't seen before:
on resume (either ACPI or APM), the LCD is left "blank"
(i.e., the backlight is on, but the console text is
not displayed).

In either case, toggling Fn-F5 (LCD/external)
brings the LCD display back to its proper state.
(APM resume in 4.x has always "just worked").

This shouldn't be a show-stopper, but it is annoying.

Has anyone encountered this behavior ?
More important, is there a solution that leaves the LCD
in its "correct" state upon resume
(i.e., without the need for the Fn-F5 intervention) ?

Pointers and discussion will be appreciated.
--
Gary E. RAFE, Ph.D. <mailto:rafege at gmail.com>
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