HDMI stereo support v5

Damien Lespiau
2013-09-19T16:40:15Z

v4 was:
http://lists.freedesktop.org/archives/dri-devel/2013-September/045340.html

Changes from v4:

- The kernel is now in charge of adjusting the stereo mode timings.
- There is a per-connector opt-in boolean to expose stereo modes, letting
people enable stereo for each driver/connector.
- The series now depends on the latest bits from the drm-intel tree
- Removed the 2 buffers check that was judged unnecessary
- I realized that for frame packing modes (where you have to adjust the
vdisplay to be 2 * vdisplay + vblank) with a NTSC clock I was
reconstructing the clock without adjusting it by 1000 / 1001. Now that the
timing computation is in the kernel, fixed it there.
- I also checked that we correctly match against the 2D CEA mode for the AVI
infoframes. The last bit to make it work was the introduction of crtc_clock
to separate the original clock from the one computed by
drm_mode_set_crtcinfo()
- And finally, I booted with i915.fastboot=1 and discovered that the pipe_src
register was getting clobbered, so fixed that as well