linux/drivers/gpu
Benson Leung caae745a35 drm/i915: Fix single msg gmbus_xfers writes
gmbus_xfer with a single message (particularly a single message write) would
set Bus Cycle Select to 100b, the Gen Stop cycle, instead of 101b,
No Index, Stop cycle. This would not start single message i2c transactions.

Also, gmbus_xfer done: will disable the interface without checking if
it is idle. In the case of writes, there will be no wait on status or delay
to ensure the write starts and completes before the interface is turned off.

Fixed the former issue by using the same cycle selection as used in the
I2C_M_RD for the write case.
GMBUS_CYCLE_WAIT | (i + 1 == num ? GMBUS_CYCLE_STOP : 0)
Fixed the latter by waiting on GMBUS_ACTIVE to deassert before disable.

Note from the grumpy d-i-n maintainer: The first hunk that changes the
gmbus read path is just cosmetics to align the code with the write
path.  I.e. the commit message above is slightly lying because the
first issue is _only_ with writes (and not simply "particularly").

Signed-off-by: Benson Leung <bleung@chromium.org>
Reviewed-by: Daniel Kurtz <djkurtz@chromium.org>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
2012-02-29 20:10:36 +01:00
..
drm drm/i915: Fix single msg gmbus_xfers writes 2012-02-29 20:10:36 +01:00
stub i915: select VIDEO_OUTPUT_CONTROL for ACPI_VIDEO 2011-04-13 09:10:25 +10:00
vga drivers/gpu/vga/vgaarb.c: add missing kfree 2011-11-22 20:21:10 +00:00
Makefile gpu: Add Intel GMA500(Poulsbo) Stub Driver 2010-10-26 11:00:13 +10:00