drm/i915: Actually retry with bit-banging after GMBUS timeout
authorVille Syrjälä <ville.syrjala@linux.intel.com>
Mon, 7 Mar 2016 15:56:57 +0000 (17:56 +0200)
committerVille Syrjälä <ville.syrjala@linux.intel.com>
Wed, 9 Mar 2016 15:06:50 +0000 (17:06 +0200)
commit8b1f165a4a8f64c28cf42d10e1f4d3b451dedc51
tree9df06b7376f9bb40bd35e5b684cd65f285fc5b35
parenta3c988ea068c94f39a2e6bd37e0faf1c2606a55d
drm/i915: Actually retry with bit-banging after GMBUS timeout

After the GMBUS transfer times out, we set force_bit=1 and
return -EAGAIN expecting the i2c core to call the .master_xfer
hook again so that we will retry the same transfer via bit-banging.
This is in case the gmbus hardware is somehow faulty.

Unfortunately we left adapter->retries to 0, meaning the i2c core
didn't actually do the retry. Let's tell the core we want one retry
when we return -EAGAIN.

Note that i2c-algo-bit also uses this retry count for some internal
retries, so we'll end up increasing those a bit as well.

Cc: Jani Nikula <jani.nikula@intel.com>
Cc: drm-intel-fixes@lists.freedesktop.org
Fixes: bffce907d640 ("drm/i915: abstract i2c bit banging fallback in gmbus xfer")
Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1457366220-29409-2-git-send-email-ville.syrjala@linux.intel.com
Reviewed-by: Jani Nikula <jani.nikula@intel.com>
drivers/gpu/drm/i915/intel_i2c.c