drm/i915: Write AVI infoframes for MCA LSPCON

LSPCON is a DP branch device, so LSPCON vendors define
specific methods to pass AVI infoframes to the the chip.
This patch adds:
- a generic wrapper function for writing AVI infoframes for
  all LSPCON devices.
- a vendor specific function to wrire AVI infoframes into
  MCA LSPCON devices.

V2: Rebase
V3: Added r-b from Maarten
V4: Rebase
V5: Rebase
V6: Rebase
V7: Fixed checkpatch warnings for alignment
V8: Rebase
V9: Added the retry logic, with 50ms incremental delays while
    writing AVI IF
V10: Changed the return value check
V11: Fixed checkpatch warning
V12: Rebase

Cc: Imre Deak <imre.deak@intel.com>
Cc: Ville Syrjälä <ville.syrjala@linux.intel.com>
Cc: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Reviewed-by: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Signed-off-by: Shashank Sharma <shashank.sharma@intel.com>
Signed-off-by: Jani Nikula <jani.nikula@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/1539325394-20788-6-git-send-email-shashank.sharma@intel.com

1 files changed, 2 insertions, 0 deletions

diff --git a/drivers/gpu/drm/i915/intel_hdmi.c b/drivers/gpu/drm/i915/intel_hdmi.c
index d2232e32a059..89d5e3984452 100644
--- a/drivers/gpu/drm/i915/intel_hdmi.c
+++ b/drivers/gpu/drm/i915/intel_hdmi.c
@@ -2322,6 +2322,8 @@ void intel_infoframe_init(struct intel_digital_port *intel_dig_port)
 		intel_dig_port->infoframe_enabled = g4x_infoframe_enabled;
 	} else if (HAS_DDI(dev_priv)) {
 		if (intel_dig_port->lspcon.active) {
+			intel_dig_port->write_infoframe =
+					lspcon_write_infoframe;
 			intel_dig_port->set_infoframes = lspcon_set_infoframes;
 			intel_dig_port->infoframe_enabled =
 						lspcon_infoframe_enabled;