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Thinkpad A21p top-open screen redraw problem (update)

Okay, I emailed the list a few days ago about this, where the closing the
top (NOT suspending the system, simply closing the computer which cause
the BIOS to turn off the LCD by default) causes some problems when the
computer is re-opened.

The first problem, that the display is garbled, has gone away by using
vesafb in the kernel.  I don't understand the relation between the problem
in the fix, but irregardless it does work.

The second problem, however, has not gone away.  Sometimes when the top is
reopened, the display simply remains blank.  The backlight comes on, but
the screen is not redrawn.  Hitting keys, moving the pointer etc have no

I have to note that I haven't yet tried switching to the console and back
to force a redraw, because of some confusion on my part.  I couldn't quite
figure out the exact keypresses necessary to do the switch (I load in my
own custom keymap, which changes which keys are used for the console
switch) and the fact that it only works if you press ctl-alt-F? in that
specific order (merely holding all three down doesn't cut it).  Also, for
some odd reason switching to tty1 (ctl-alt-f1) doesn't do anything, but
the switch to tty2-tty6 works just fine.

Even if ctl-alt-f2 is a suitable workaround (certainly a lot better than
going into and then out of a full suspend, which _always_ works) this
really shouldn't be happening in the first place.  It's irritating.

A friend of mine has suggested this may be related to kernel-based console
blanking, which might explain why input to the X server doesn't cause the
screen to come back.  Does anyone have any suggestions as to how to
disable console blanking entirely?  Since the bios seems to handle this
more intellegently than linux can, and LCDs don't suffer from burn-in (at
least I don't think they do?), standard console blanking (which leaves on
the battery-eating backlight anyhow [1]) is completely useless to me.

[1] There is a kernel option that will make some sort of apm standby call.  
I have that turned off.  Does anyone know what exactly the effect of that
option on an A series thinkpad is?

I appreciate any suggestions in fixing this!

           ------------------ Peter Amstutz --------------------
           ---------------- amstutz@cs.umass.edu ---------------
           ------- http://www-unix.oit.umass.edu/~tetron -------

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