drm/i915: Add intel_bios_cleanup() function

Add an intel_bios_cleanup() function to act as counterpart of
intel_bios_init() and move the cleanup of vbt related resources there,
putting it in the same file as the allocation.

Changed in v2:
-While touching the code anyways, remove the unnecessary:
 if (dev_priv->vbt.child_dev) done before kfree(dev_priv->vbt.child_dev)
Reviewed-by: NVille Syrjälä <ville.syrjala@linux.intel.com>
Signed-off-by: NHans de Goede <hdegoede@redhat.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20180214082151.25015-1-hdegoede@redhat.com
(cherry picked from commit 785f076b)
Signed-off-by: NRodrigo Vivi <rodrigo.vivi@intel.com>

drivers/gpu/drm/i915/i915_drv.c

@@ -1433,19 +1433,7 @@ void i915_driver_unload(struct drm_device *dev)
 
 	intel_modeset_cleanup(dev);
 
-	/*
-	 * free the memory space allocated for the child device
-	 * config parsed from VBT
-	 */
-	if (dev_priv->vbt.child_dev && dev_priv->vbt.child_dev_num) {
-		kfree(dev_priv->vbt.child_dev);
-		dev_priv->vbt.child_dev = NULL;
-		dev_priv->vbt.child_dev_num = 0;
-	}
-	kfree(dev_priv->vbt.sdvo_lvds_vbt_mode);
-	dev_priv->vbt.sdvo_lvds_vbt_mode = NULL;
-	kfree(dev_priv->vbt.lfp_lvds_vbt_mode);
-	dev_priv->vbt.lfp_lvds_vbt_mode = NULL;
+	intel_bios_cleanup(dev_priv);
 
 	vga_switcheroo_unregister_client(pdev);
 	vga_client_register(pdev, NULL, NULL, NULL);

drivers/gpu/drm/i915/i915_drv.h

@@ -3657,6 +3657,7 @@ extern void intel_i2c_reset(struct drm_i915_private *dev_priv);
 
 /* intel_bios.c */
 void intel_bios_init(struct drm_i915_private *dev_priv);
+void intel_bios_cleanup(struct drm_i915_private *dev_priv);
 bool intel_bios_is_valid_vbt(const void *buf, size_t size);
 bool intel_bios_is_tv_present(struct drm_i915_private *dev_priv);
 bool intel_bios_is_lvds_present(struct drm_i915_private *dev_priv, u8 *i2c_pin);

drivers/gpu/drm/i915/intel_bios.c

@@ -1588,6 +1588,21 @@ void intel_bios_init(struct drm_i915_private *dev_priv)
 		pci_unmap_rom(pdev, bios);
 }
 
+/**
+ * intel_bios_cleanup - Free any resources allocated by intel_bios_init()
+ * @dev_priv: i915 device instance
+ */
+void intel_bios_cleanup(struct drm_i915_private *dev_priv)
+{
+	kfree(dev_priv->vbt.child_dev);
+	dev_priv->vbt.child_dev = NULL;
+	dev_priv->vbt.child_dev_num = 0;
+	kfree(dev_priv->vbt.sdvo_lvds_vbt_mode);
+	dev_priv->vbt.sdvo_lvds_vbt_mode = NULL;
+	kfree(dev_priv->vbt.lfp_lvds_vbt_mode);
+	dev_priv->vbt.lfp_lvds_vbt_mode = NULL;
+}
+
 /**
  * intel_bios_is_tv_present - is integrated TV present in VBT
  * @dev_priv:	i915 device instance