On my APL the LSPCON firmware resumes in PCON mode as opposed to the
expected LS mode. It also appears to be in a state where AUX DPCD reads
will succeed but return garbage recovering only after a few hundreds of
milliseconds. After the recovery time DPCD reads will result in the
correct values and things will continue to work. If I2C over AUX is
attempted during this recovery time (implying an AUX write transaction)
the firmware won't recover and will stay in this broken state.
As a workaround check if the firmware is in PCON state after resume and
if so wait until the correct DPCD values are returned. For this we
compare the branch descriptor with the one we cached during init time.
If the firmware was in the LS state, we skip the w/a and continue as
before.
v2:
- Use the DP descriptor value cached in intel_dp. (Jani)
- Get to intel_dp using container_of(), instead of a cached ptr.
(Shashank)
- Use usleep_range() instead of msleep().
Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=98353
Cc: Shashank Sharma <shashank.sharma@intel.com>
Cc: Ville Syrjälä <ville.syrjala@linux.intel.com>
Cc: Jani Nikula <jani.nikula@intel.com>
Signed-off-by: Imre Deak <imre.deak@intel.com>
Reviewed-by: Jani Nikula <jani.nikula@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1477326811-30431-9-git-send-email-imre.deak@intel.com
This patch adds a new file, to accommodate lspcon support
for I915 driver. These functions probe, detect, initialize
and configure an on-board lspcon device during the driver
init time.
Also, this patch adds a small structure for lspcon device,
which will provide the runtime status of the device.
V2: addressed ville's review comments
- Clean the leftover macros from previous patch set
V3: Rebase
V4: addressed ville's review comments
- make internal functions static
- remove lspcon_detect_identifier, make it inline with lspcon_probe
- remove is_lspcon_active function
- remove force check while setting a lspcon mode
V5: Rebase
V6: Pass dev_priv to IS_GEN9 check
Signed-off-by: Shashank Sharma <shashank.sharma@intel.com>
Signed-off-by: Akashdeep Sharma <akashdeep.sharma@intel.com>
Reviewed-by: Rodrigo Vivi <rodrigo.vivi@intel.com>
Acked-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Signed-off-by: Jani Nikula <jani.nikula@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1476455212-27893-3-git-send-email-shashank.sharma@intel.com
