#9690 NORM 1.5-sof: suspend/resume from VT sometimes causes spurious linefreeds

[Zarro Boogs per Child]

#9690: suspend/resume from VT sometimes causes spurious linefreeds
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           Reporter:  pgf           |       Owner:                                   
               Type:  defect        |      Status:  new                              
           Priority:  normal        |   Milestone:  1.5-software-later               
          Component:  not assigned  |     Version:  Development build as of this date
         Resolution:                |    Keywords:                                   
        Next_action:  diagnose      |    Verified:  0                                
Deployment_affected:                |   Blockedby:                                   
           Blocking:                |  
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Comment(by dsd):

 The attachment I posted above hints at an EC bug or something else going
 wrong at low-level. Look at the sequence of events:

 {{{
 key up pressed:
 [  106.685408] drivers/input/serio/i8042.c: e0 <- i8042 (interrupt, 0, 1)
 [10342]
 [  106.687323] drivers/input/serio/i8042.c: 48 <- i8042 (interrupt, 0, 1)
 [10342]

 enter pressed:
 [  106.826487] drivers/input/serio/i8042.c: 1c <- i8042 (interrupt, 0, 1)
 [10356]
 [  106.832224] PM: Syncing filesystems ... done.
 [  106.848542] PM: Preparing system for mem sleep
 [  106.848555] Freezing user space processes ... (elapsed 0.01 seconds)
 done.
 [  106.860317] Freezing remaining freezable tasks ... (elapsed 0.00
 seconds) done.
 [  106.860418] PM: Entering mem sleep

 key up released:
 [  106.875824] drivers/input/serio/i8042.c: e0 <- i8042 (interrupt, 0, 1)
 [10361]
 [  106.878300] drivers/input/serio/i8042.c: c8 <- i8042 (interrupt, 0, 1)
 [10361]

 snip snip snip

 [  107.040511] ACPI: Preparing to enter system sleep state S3
 [  107.140018] olpc-pm-1.5: wakeup_source is 'power button'
 [  107.140018] Back to C!

 snip

 suspicious line:
 [  107.220386] drivers/input/serio/i8042.c: Interrupt 1, without any data
 [10396]

 snip snip

 enter pressed (this is when I start jamming at the keys after resume)
 [  108.176062] drivers/input/serio/i8042.c: 1c <- i8042 (interrupt, 0, 1)
 [10491]

 enter released
 [  108.305031] drivers/input/serio/i8042.c: 9c <- i8042 (interrupt, 0, 1)
 [10504]
 }}}

 we're missing an "enter released" event from when i pressed it the first
 time, and note the suspicious interrupt with no data

-- 
Ticket URL: <http://dev.laptop.org/ticket/9690#comment:10>
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