[PATCH v4 2/6] drm/i915/pxp: add device link between i915 and mei_pxp

[Alan Previn]

From: Alexander Usyskin <alexander.usyskin at intel.com>

Add device link with i915 as consumer and mei_pxp as supplier
to ensure proper ordering of power flows.

V2: condition on absence of heci_pxp to filter out DG

Signed-off-by: Alexander Usyskin <alexander.usyskin at intel.com>
Signed-off-by: Alan Previn <alan.previn.teres.alexis at intel.com>
---
 drivers/gpu/drm/i915/pxp/intel_pxp_tee.c | 7 +++++++
 1 file changed, 7 insertions(+)

diff --git a/drivers/gpu/drm/i915/pxp/intel_pxp_tee.c b/drivers/gpu/drm/i915/pxp/intel_pxp_tee.c
index d50354bfb993..bef6d7f8ac55 100644
--- a/drivers/gpu/drm/i915/pxp/intel_pxp_tee.c
+++ b/drivers/gpu/drm/i915/pxp/intel_pxp_tee.c
@@ -127,6 +127,10 @@ static int i915_pxp_tee_component_bind(struct device *i915_kdev,
 	intel_wakeref_t wakeref;
 	int ret = 0;
 
+	if (!HAS_HECI_PXP(i915) &&
+	    drm_WARN_ON(&i915->drm, !device_link_add(i915_kdev, tee_kdev, DL_FLAG_STATELESS)))
+		return -ENOMEM;
+
 	mutex_lock(&pxp->tee_mutex);
 	pxp->pxp_component = data;
 	pxp->pxp_component->tee_dev = tee_kdev;
@@ -169,6 +173,9 @@ static void i915_pxp_tee_component_unbind(struct device *i915_kdev,
 	mutex_lock(&pxp->tee_mutex);
 	pxp->pxp_component = NULL;
 	mutex_unlock(&pxp->tee_mutex);
+
+	if (!HAS_HECI_PXP(i915))
+		device_link_remove(i915_kdev, tee_kdev);
 }
 
 static const struct component_ops i915_pxp_tee_component_ops = {
-- 
2.39.0