#6573 NORM Never A: i8042 mouse reset fails when game keys are pressed

[Zarro Boogs per Child]

#6573: i8042 mouse reset fails when game keys are pressed
---------------------------------+------------------------------------------
 Reporter:  JordanCrouse         |       Owner:  rsmith        
     Type:  defect               |      Status:  new           
 Priority:  normal               |   Milestone:  Never Assigned
Component:  embedded controller  |     Version:                
 Keywords:                       |    Verified:  0             
 Blocking:                       |   Blockedby:                
---------------------------------+------------------------------------------
 Issuing a reset to the mouse via i8042 is supposed to return three bytes:
 0xFF, 0x00, 0xAA.  OFW recipe (with a USB keyboard, natch):
 {{{
 ok d4 64 pc!
 ok ff 60 pc!
 ok 60 pc@ .
 fa
 ok 60 pc@ .
 00
 ok 60 pc@ .
 ff
 }}}

 But, if a game key is pressed when the reset gets sent to the mouse (0xFF
 -> 0x60), the acknowledgment is screwed up:

 {{{
 ok d4 64 pc!
 ok ff 60 pc!
 ok 60 pc@ .
 e0
 ok 60 pc@ .
 00
 ok 60 pc@ .
 aa
 }}}

 Note the 0xe0 in the place of the 0xfa (the 0xe0 is from the keypress, I
 believe).  So either the ACK never happens, or it gets misplaced in the
 queue.  I'm a fan of the latter theory, because the 0x00 and 0xaa come as
 expected.  This may be related to #6544 and other "bad stuff happens when
 the game keys are pressed" bugs.

-- 
Ticket URL: <http://dev.laptop.org/ticket/6573>
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