This patchset addresses a couple of issues with the i915 gmbus implementation: * fixes misassigned pin port pair for HDMI-D * fixes write transactions when they are the only transaction requested (including large >4-byte writes) by terminating every transaction with a WAIT cycle. * returns -ENXIO and -ETIMEDOUT as appropriate so upper layers can handled i2c transaction failures * optimizes the typical read transaction case by using the INDEX cycle * turns on the GMBUS interrupt whenever possible to dramatically improve throughput by eliminating the very slow polling loop.
The patchset should apply cleanly onto linus/master. It is inspired by, but completely supercedes, a similar patch submitted recently by Benson Leung (bleung@chromium.org). I'd be happy to rebase on a different tree if necessary.
v2 of the patchset address review comments from Chris Wilson (thanks for the review, Chris!), and adds the interrupt patch. There weren't any review comments for patches 5, 7, or 8 of the first set. Hopefully they will get more love the second time around :).
Daniel Kurtz (10): drm/i915/intel_i2c: cleanup drm/i915/intel_i2c: assign HDMI port D to pin pair 6 drm/i915/intel_i2c: refactor using intel_gmbus_get_adapter drm/i915/intel_i2c: cleanup gmbus/gpio pin assignments drm/i915/intel_i2c: add locking around i2c algorithm accesses drm/i915/intel_i2c: return -ENXIO for device NAK drm/i915/intel_i2c: use WAIT cycle, not STOP drm/i915/intel_i2c: use INDEX cycles for i2c read transactions drm/i915/intel_i2c: reuse GMBUS2 value read in polling loop drm/i915/intel_i2c: enable gmbus interrupts
drivers/gpu/drm/i915/i915_drv.h | 7 +- drivers/gpu/drm/i915/i915_irq.c | 22 +++- drivers/gpu/drm/i915/i915_reg.h | 6 +- drivers/gpu/drm/i915/intel_bios.c | 11 +- drivers/gpu/drm/i915/intel_crt.c | 13 +- drivers/gpu/drm/i915/intel_drv.h | 9 ++- drivers/gpu/drm/i915/intel_dvo.c | 4 +- drivers/gpu/drm/i915/intel_hdmi.c | 29 ++--- drivers/gpu/drm/i915/intel_i2c.c | 236 ++++++++++++++++++++++++++++-------- drivers/gpu/drm/i915/intel_lvds.c | 3 +- drivers/gpu/drm/i915/intel_modes.c | 6 +- drivers/gpu/drm/i915/intel_sdvo.c | 10 +- 12 files changed, 257 insertions(+), 99 deletions(-)