drm/i915/opregion: abstract ASLE presence check

Add a function to check the opregion ASLE presence instead of accessing
the opregion structures directly.

Reorder the checks in i915_has_asle() to avoid the function call if
possible.

Cc: Radhakrishna Sripada <radhakrishna.sripada@intel.com>
Reviewed-by: Radhakrishna Sripada <radhakrishna.sripada@intel.com>
Signed-off-by: Jani Nikula <jani.nikula@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/1829415d3e7b29e78c46b20bca8175ef373bcd92.1704992868.git.jani.nikula@intel.com

drivers/gpu/drm/i915/display/intel_display_irq.c

@@ -266,12 +266,12 @@ void i915_disable_pipestat(struct drm_i915_private *dev_priv,
 	intel_uncore_posting_read(&dev_priv->uncore, reg);
 }
 
-static bool i915_has_asle(struct drm_i915_private *dev_priv)
+static bool i915_has_asle(struct drm_i915_private *i915)
 {
-	if (!dev_priv->display.opregion.asle)
+	if (!IS_PINEVIEW(i915) && !IS_MOBILE(i915))
 		return false;
 
-	return IS_PINEVIEW(dev_priv) || IS_MOBILE(dev_priv);
+	return intel_opregion_asle_present(i915);
 }
 
 /**

drivers/gpu/drm/i915/display/intel_opregion.c

@@ -632,6 +632,11 @@ static void asle_work(struct work_struct *work)
 	asle->aslc = aslc_stat;
 }
 
+bool intel_opregion_asle_present(struct drm_i915_private *i915)
+{
+	return i915->display.opregion.asle;
+}
+
 void intel_opregion_asle_intr(struct drm_i915_private *dev_priv)
 {
 	if (dev_priv->display.opregion.asle)

drivers/gpu/drm/i915/display/intel_opregion.h

@@ -69,6 +69,7 @@ void intel_opregion_resume(struct drm_i915_private *dev_priv);
 void intel_opregion_suspend(struct drm_i915_private *dev_priv,
 			    pci_power_t state);
 
+bool intel_opregion_asle_present(struct drm_i915_private *i915);
 void intel_opregion_asle_intr(struct drm_i915_private *dev_priv);
 int intel_opregion_notify_encoder(struct intel_encoder *intel_encoder,
 				  bool enable);
@@ -111,6 +112,11 @@ static inline void intel_opregion_suspend(struct drm_i915_private *dev_priv,
 {
 }
 
+static inline bool intel_opregion_asle_present(struct drm_i915_private *i915)
+{
+	return false;
+}
+
 static inline void intel_opregion_asle_intr(struct drm_i915_private *dev_priv)
 {
 }