drm/i915: Compile out error state without DEBUG_FS

Alexander reported that the compilation of intel_overlay.c was failing
due to an inclusion that was only valid with CONFIG_DEBUG_FS. As the
whole error reporting is only useful with debugfs enabled, remove all
the redundant error state collection code when compiling without
CONFIG_DEBUG_FS.

Reported-by: Alexander Lam <lambchop468@gmail.com>
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
diff --git a/drivers/gpu/drm/i915/i915_drv.h b/drivers/gpu/drm/i915/i915_drv.h
index 1016073..634e1c46 100644
--- a/drivers/gpu/drm/i915/i915_drv.h
+++ b/drivers/gpu/drm/i915/i915_drv.h
@@ -874,7 +874,6 @@
 
 /* i915_irq.c */
 void i915_hangcheck_elapsed(unsigned long data);
-void i915_destroy_error_state(struct drm_device *dev);
 extern int i915_irq_emit(struct drm_device *dev, void *data,
 			 struct drm_file *file_priv);
 extern int i915_irq_wait(struct drm_device *dev, void *data,
@@ -911,6 +910,12 @@
 
 void intel_enable_asle (struct drm_device *dev);
 
+#ifdef CONFIG_DEBUG_FS
+extern void i915_destroy_error_state(struct drm_device *dev);
+#else
+#define i915_destroy_error_state(x)
+#endif
+
 
 /* i915_mem.c */
 extern int i915_mem_alloc(struct drm_device *dev, void *data,
@@ -1091,8 +1096,10 @@
 extern int intel_trans_dp_port_sel (struct drm_crtc *crtc);
 
 /* overlay */
+#ifdef CONFIG_DEBUG_FS
 extern struct intel_overlay_error_state *intel_overlay_capture_error_state(struct drm_device *dev);
 extern void intel_overlay_print_error_state(struct seq_file *m, struct intel_overlay_error_state *error);
+#endif
 
 /**
  * Lock test for when it's just for synchronization of ring access.
diff --git a/drivers/gpu/drm/i915/i915_irq.c b/drivers/gpu/drm/i915/i915_irq.c
index e797157..080ea3b 100644
--- a/drivers/gpu/drm/i915/i915_irq.c
+++ b/drivers/gpu/drm/i915/i915_irq.c
@@ -421,6 +421,7 @@
 	}
 }
 
+#ifdef CONFIG_DEBUG_FS
 static struct drm_i915_error_object *
 i915_error_object_create(struct drm_device *dev,
 			 struct drm_gem_object *src)
@@ -744,6 +745,9 @@
 	if (error)
 		i915_error_state_free(dev, error);
 }
+#else
+#define i915_capture_error_state(x)
+#endif
 
 static void i915_report_and_clear_eir(struct drm_device *dev)
 {
diff --git a/drivers/gpu/drm/i915/intel_overlay.c b/drivers/gpu/drm/i915/intel_overlay.c
index bb2256f..743ced7 100644
--- a/drivers/gpu/drm/i915/intel_overlay.c
+++ b/drivers/gpu/drm/i915/intel_overlay.c
@@ -190,31 +190,6 @@
 };
 
 static struct overlay_registers *
-intel_overlay_map_regs_atomic(struct intel_overlay *overlay,
-			      int slot)
-{
-        drm_i915_private_t *dev_priv = overlay->dev->dev_private;
-	struct overlay_registers *regs;
-
-	if (OVERLAY_NEEDS_PHYSICAL(overlay->dev))
-		regs = overlay->reg_bo->phys_obj->handle->vaddr;
-	else
-		regs = io_mapping_map_atomic_wc(dev_priv->mm.gtt_mapping,
-						overlay->reg_bo->gtt_offset,
-						slot);
-
-	return regs;
-}
-
-static void intel_overlay_unmap_regs_atomic(struct intel_overlay *overlay,
-					    int slot,
-					    struct overlay_registers *regs)
-{
-	if (!OVERLAY_NEEDS_PHYSICAL(overlay->dev))
-		io_mapping_unmap_atomic(regs, slot);
-}
-
-static struct overlay_registers *
 intel_overlay_map_regs(struct intel_overlay *overlay)
 {
         drm_i915_private_t *dev_priv = overlay->dev->dev_private;
@@ -1454,6 +1429,9 @@
 	kfree(dev_priv->overlay);
 }
 
+#ifdef CONFIG_DEBUG_FS
+#include <linux/seq_file.h>
+
 struct intel_overlay_error_state {
 	struct overlay_registers regs;
 	unsigned long base;
@@ -1461,6 +1439,32 @@
 	u32 isr;
 };
 
+static struct overlay_registers *
+intel_overlay_map_regs_atomic(struct intel_overlay *overlay,
+			      int slot)
+{
+        drm_i915_private_t *dev_priv = overlay->dev->dev_private;
+	struct overlay_registers *regs;
+
+	if (OVERLAY_NEEDS_PHYSICAL(overlay->dev))
+		regs = overlay->reg_bo->phys_obj->handle->vaddr;
+	else
+		regs = io_mapping_map_atomic_wc(dev_priv->mm.gtt_mapping,
+						overlay->reg_bo->gtt_offset,
+						slot);
+
+	return regs;
+}
+
+static void intel_overlay_unmap_regs_atomic(struct intel_overlay *overlay,
+					    int slot,
+					    struct overlay_registers *regs)
+{
+	if (!OVERLAY_NEEDS_PHYSICAL(overlay->dev))
+		io_mapping_unmap_atomic(regs, slot);
+}
+
+
 struct intel_overlay_error_state *
 intel_overlay_capture_error_state(struct drm_device *dev)
 {
@@ -1549,3 +1553,4 @@
 	P(UVSCALEV);
 #undef P
 }
+#endif