drm/i915: Init power domains early in driver load

Since

commit ac9b8236551d1177fd07b56aef9b565d1864420d
Author: Ville Syrjälä <ville.syrjala@linux.intel.com>
Date:   Fri Nov 27 18:55:26 2015 +0200

    drm/i915: Introduce a gmbus power domain

gmbus also needs the power domain infrastructure right from the start,
since as soon as we register the i2c controllers someone can use them.

v2: Adjust cleanup paths too (Chris).

v3: Rebase onto -nightly (totally bogus tree I had lying around) and
also move dpio init head (Ville).

v4: Ville instead suggested to move gmbus setup later in the sequence,
since it's only needed by the modeset code.

v5: Move even close to the actual user, right next to the comment that
states where we really need gmbus (and interrupts!).

Cc: Ville Syrjälä <ville.syrjala@linux.intel.com>
Cc: Patrik Jakobsson <patrik.jakobsson@linux.intel.com>
Cc: Imre Deak <imre.deak@intel.com>
Cc: Jani Nikula <jani.nikula@intel.com>
Cc: Meelis Roos <mroos@linux.ee>
Cc: Chris Wilson <chris@chris-wilson.co.uk>
Fixes: ac9b8236551d ("drm/i915: Introduce a gmbus power domain")
Cc: stable@vger.kernel.org
References: http://www.spinics.net/lists/intel-gfx/msg83075.html
Signed-off-by: Daniel Vetter <daniel.vetter@intel.com>
Reviewed-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1452682528-19437-1-git-send-email-daniel.vetter@ffwll.ch
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>

drivers/gpu/drm/i915/i915_dma.c

@@ -403,6 +403,8 @@ static int i915_load_modeset_init(struct drm_device *dev)
 	if (ret)
 		goto cleanup_gem_stolen;
 
+	intel_setup_gmbus(dev);
+
 	/* Important: The output setup functions called by modeset_init need
 	 * working irqs for e.g. gmbus and dp aux transfers. */
 	intel_modeset_init(dev);
@@ -452,6 +454,7 @@ cleanup_gem:
 cleanup_irq:
 	intel_guc_ucode_fini(dev);
 	drm_irq_uninstall(dev);
+	intel_teardown_gmbus(dev);
 cleanup_gem_stolen:
 	i915_gem_cleanup_stolen(dev);
 cleanup_vga_switcheroo:
@@ -1026,7 +1029,6 @@ int i915_driver_load(struct drm_device *dev, unsigned long flags)
 
 	/* Try to make sure MCHBAR is enabled before poking at it */
 	intel_setup_mchbar(dev);
-	intel_setup_gmbus(dev);
 	intel_opregion_setup(dev);
 
 	i915_gem_load(dev);
@@ -1097,7 +1099,6 @@ out_gem_unload:
 	if (dev->pdev->msi_enabled)
 		pci_disable_msi(dev->pdev);
 
-	intel_teardown_gmbus(dev);
 	intel_teardown_mchbar(dev);
 	pm_qos_remove_request(&dev_priv->pm_qos);
 	destroy_workqueue(dev_priv->gpu_error.hangcheck_wq);
@@ -1196,7 +1197,6 @@ int i915_driver_unload(struct drm_device *dev)
 
 	intel_csr_ucode_fini(dev_priv);
 
-	intel_teardown_gmbus(dev);
 	intel_teardown_mchbar(dev);
 
 	destroy_workqueue(dev_priv->hotplug.dp_wq);

drivers/gpu/drm/i915/intel_display.c

@@ -15821,6 +15821,8 @@ void intel_modeset_cleanup(struct drm_device *dev)
 	mutex_lock(&dev->struct_mutex);
 	intel_cleanup_gt_powersave(dev);
 	mutex_unlock(&dev->struct_mutex);
+
+	intel_teardown_gmbus(dev);
 }
 
 /*