#12090 NORM 13.1.0: XO-4 camera not working in Linux

Zarro Boogs per Child bugtracker at laptop.org
Wed Sep 5 17:10:12 EDT 2012

#12090: XO-4 camera not working in Linux
           Reporter:  dsd                  |       Owner:  dsd          
               Type:  defect               |      Status:  new          
           Priority:  normal               |   Milestone:  13.1.0       
          Component:  ofw - open firmware  |     Version:  not specified
         Resolution:                       |    Keywords:               
        Next_action:  package              |    Verified:  0            
Deployment_affected:                       |   Blockedby:               
           Blocking:                       |  
Changes (by dsd):

  * next_action:  diagnose => package
  * component:  kernel => ofw - open firmware


 To check if the IRQ is masked:

 irq-reg 1b4 + l@ .

 (it was)

 Mitch found 2 errors in the firmware. First of all the firmware was
 pointing to mask register 1bf for IRQ42, but it should be 1b4. That fixed
 the unmasking of bit 0 in that register, but image capture was still

 Then we unmasked all the IRQs in that space:
 0 irq-reg 1b4 + l!

 and an interrupt arrived on IRQ42. That was the 2nd error, confusingly
 CCIC2 is at bit 0, but CCIC1 (where the camera is) is at bit 1.

 With the firmware fixed, Linux now correctly unmasks the IRQ and things
 start working.

Ticket URL: <http://dev.laptop.org/ticket/12090#comment:3>
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