After a suspend/resume cycle with X/Radeon driver having initialized the
secondary head display, it goes irrevocably garbled (need for reboot to bring
things back to normal).

Steps to reproduce:
 - Start X utilising both the primary and secondary head of the graphics adapter
(in my case an IGP340 or IGP350)
 - Invoke a suspend
 - Resume
 - Primary head resumes operation, but not the secondary head.

Shutting down X, and restarting it brings back the garbled display. It requires
a reboot to restore the secondary display's image.

See these images for an example:

Normal operation:
 http://q1.se/files/ati_drv/img_1713.jpg

After resume, garbled secondary display:
 http://q1.se/files/ati_drv/img_1715.jpg

Closeup of garbled display with garbled mouse cursor:
 http://q1.se/files/ati_drv/img_1722.jpg
 
Module information:
(II) Module radeon: vendor="X.Org Foundation"
        compiled for 6.7.0, module version = 4.0.1
        Module class: X.Org Video Driver
        ABI class: X.Org Video Driver, version 0.7

lspci -v of the graphics adapter:
0000:01:05.0 VGA compatible controller: ATI Technologies Inc Radeon IGP 340M
(prog-if 00 [VGA])
        Subsystem: Compaq Computer Corporation: Unknown device 005a
        Flags: bus master, stepping, 66MHz, medium devsel, latency 64, IRQ 10
        Memory at 98000000 (32-bit, prefetchable) [size=128M]
        I/O ports at 2000 [size=256]
        Memory at 90000000 (32-bit, non-prefetchable) [size=64K]
        Expansion ROM at <unassigned> [disabled] [size=128K]
        Capabilities: [58] AGP version 2.0
        Capabilities: [50] Power Management version 2

Problem has existed in all drivers tested so far (xfree86 driver from 4.3, from
DRI CVS, and X.org's driver)