[PATCH] drm/i915/icl: Add TypeC ports only if VBT is present

Imre Deak
2019-01-25T14:34:44Z

We can't safely probe Type C ports, whether they are a legacy or a
USB/Thunderbolt DP Alternate Type C port. This would require performing
the TypeC connect sequence - as described by the specification - but
that may have unwanted side-effects. These side-effects include at least
- without completeness - timeouts during AUX power well enabling and
subsequent PLL enabling errors.

To safely identify these ports we really need VBT, which has the proper
flag for this (ddi_vbt_port_info::supports_typec_usb, supports_tbt).
Based on the above disable Type C ports if we can't load VBT for some
reason.

Cc: Jani Nikula <jani.nikula@intel.com>
Cc: Paulo Zanoni <paulo.r.zanoni@intel.com>
Cc: Jose Roberto de Souza <jose.souza@intel.com>
Cc: Ville Syrjälä <ville.syrjala@linux.intel.com>
Cc: Rodrigo Vivi <rodrigo.vivi@intel.com>
Signed-off-by: Imre Deak <imre.deak@intel.com>
---
drivers/gpu/drm/i915/intel_bios.c | 6 ++++--
1 file changed, 4 insertions(+), 2 deletions(-)

diff --git a/drivers/gpu/drm/i915/intel_bios.c b/drivers/gpu/drm/i915/intel_bios.c
index 561a4f9f044c..270e7f0ad5cd 100644
--- a/drivers/gpu/drm/i915/intel_bios.c
+++ b/drivers/gpu/drm/i915/intel_bios.c
@@ -1662,10 +1662,12 @@ init_vbt_missing_defaults(struct drm_i915_private *dev_priv)
for (port = PORT_A; port < I915_MAX_PORTS; port++) {
struct ddi_vbt_port_info *info =
&dev_priv->vbt.ddi_port_info[port];
+ bool is_tc_port = intel_port_is_tc(dev_priv, port);

- info->supports_dvi = (port != PORT_A && port != PORT_E);
+ info->supports_dvi = (port != PORT_A && port != PORT_E &&
+ !is_tc_port);
info->supports_hdmi = info->supports_dvi;
- info->supports_dp = (port != PORT_E);
+ info->supports_dp = (port != PORT_E && !is_tc_port);
}
}

--
2.13.2