Manual and options for the "modesetting" driver

[Stefan Monnier]

> I do
> $ xrandr --setprovideroutputsource 1 0

IIUC this is to tell one GPU to render into another card's framebuffer.
I don't have any GPUs, I only have framebuffers (well, Poulsbo does
include a GPU, but I have no driver for that part).

In any case, it fails (and it doesn't solve my gdm-rotation problem either):

   % DISPLAY=:0 xrandr                              
   Screen 0: minimum 320 x 200, current 1200 x 1600, maximum 4096 x 4096
   DVI-0 connected 1200x1600+0+0 left (normal left inverted right x axis y axis) 432mm x 324mm
      1600x1200     60.00*+  54.88  
      1280x1024     75.02    60.02  
      1280x960      60.00  
      1152x864      75.00  
      1024x768      75.08    70.07    60.00  
      832x624       74.55  
      800x600       72.19    75.00    60.32    56.25  
      640x480       75.00    72.81    66.67    60.00  
      720x400       70.08  
   % DISPLAY=:0 xrandr --listproviders              
   Providers: number : 2
   Provider 0: id: 0x77 cap: 0x0 crtcs: 2 outputs: 1 associated providers: 0 name:modesetting
   Provider 1: id: 0x41 cap: 0x2, Sink Output crtcs: 1 outputs: 1 associated providers: 0 name:modesetting
   % DISPLAY=:0 xrandr --setprovideroutputsource 1 0
   X Error of failed request:  BadValue (integer parameter out of range for operation)
     Major opcode of failed request:  140 (RANDR)
     Minor opcode of failed request:  35 (RRSetProviderOutputSource)
     Value in failed request:  0x77
     Serial number of failed request:  16
     Current serial number in output stream:  17


-- Stefan