[Trac #1382] "reboot" from Linux just gives black screen on LX

[Zarro Boogs per Child]

#1382: "reboot" from Linux just gives black screen on LX
---------------------+------------------------------------------------------
 Reporter:  cjb      |        Owner:  dilinger
     Type:  defect   |       Status:  new     
 Priority:  blocker  |    Milestone:  BTest-3 
Component:  kernel   |   Resolution:          
 Keywords:           |  
---------------------+------------------------------------------------------
Comment (by dilinger):

 Bizarre.  After adding the following to the dcon's reboot notifier:
 {{{
 printk(KERN_WARNING "turning off dcon\n");
         /* Turn off the DCON. Entirely. */
         dcon_write(DCON_REG_MODE, 0x39);
         dcon_write(DCON_REG_MODE, 0x32);
 printk(KERN_WARNING "dcon is now off, sleeping for a bit\n");
 mdelay(5000);
 printk(KERN_WARNING "done sleeping!\n");
 }}}

 Produces:

 {{{
  [   70.717948] turning off dcon
 [   70.722055] dcon is now off, sleeping for a bit
 [   75.739379] done sleeping!
 [   76.650648] Restarting system.
 }}}

 During the sleep, the dcon turns off (completely).  After the sleep is
 done, the dcon turns back on; something in the kernel (or perhaps
 something the kernel is frobbing) is causing the dcon to turn back on
 before the machine shuts down!

-- 
Ticket URL: <http://dev.laptop.org/ticket/1382#comment:8>
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