drm/i915: extract intel_combo_phy.h from i915_drv.h

It used to be handy that we only had a couple of headers, but over time
i915_drv.h has become unwieldy. Extract declarations to a separate
header file corresponding to the implementation module, clarifying the
modularity of the driver.

Ensure the new header is self-contained, and do so with minimal further
includes, using forward declarations as needed. Include the new header
only where needed, and sort the modified include directives while at it
and as needed.

No functional changes.
Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Jani Nikula <jani.nikula@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/6aea17072684dec0b04b6831c0c0e5a134edf87e.1556540890.git.jani.nikula@intel.com

drivers/gpu/drm/i915/Makefile.header-test

@@ -19,6 +19,7 @@ header_test := \
 	intel_bios.h \
 	intel_cdclk.h \
 	intel_color.h \
+	intel_combo_phy.h \
 	intel_connector.h \
 	intel_crt.h \
 	intel_csr.h \

drivers/gpu/drm/i915/i915_drv.h

@@ -3364,12 +3364,6 @@ void vlv_phy_pre_encoder_enable(struct intel_encoder *encoder,
 void vlv_phy_reset_lanes(struct intel_encoder *encoder,
 			 const struct intel_crtc_state *old_crtc_state);
 
-/* intel_combo_phy.c */
-void icl_combo_phys_init(struct drm_i915_private *dev_priv);
-void icl_combo_phys_uninit(struct drm_i915_private *dev_priv);
-void cnl_combo_phys_init(struct drm_i915_private *dev_priv);
-void cnl_combo_phys_uninit(struct drm_i915_private *dev_priv);
-
 #define __I915_REG_OP(op__, dev_priv__, ...) \
 	intel_uncore_##op__(&(dev_priv__)->uncore, __VA_ARGS__)
 

drivers/gpu/drm/i915/intel_combo_phy.c

@@ -3,6 +3,7 @@
  * Copyright © 2018 Intel Corporation
  */
 
+#include "intel_combo_phy.h"
 #include "intel_drv.h"
 
 #define for_each_combo_port(__dev_priv, __port) \

drivers/gpu/drm/i915/intel_combo_phy.h

+/* SPDX-License-Identifier: MIT */
+/*
+ * Copyright © 2019 Intel Corporation
+ */
+
+#ifndef __INTEL_COMBO_PHY_H__
+#define __INTEL_COMBO_PHY_H__
+
+struct drm_i915_private;
+
+void icl_combo_phys_init(struct drm_i915_private *dev_priv);
+void icl_combo_phys_uninit(struct drm_i915_private *dev_priv);
+void cnl_combo_phys_init(struct drm_i915_private *dev_priv);
+void cnl_combo_phys_uninit(struct drm_i915_private *dev_priv);
+
+#endif /* __INTEL_COMBO_PHY_H__ */

drivers/gpu/drm/i915/intel_runtime_pm.c

@@ -34,6 +34,7 @@
 #include "i915_drv.h"
 #include "i915_irq.h"
 #include "intel_cdclk.h"
+#include "intel_combo_phy.h"
 #include "intel_crt.h"
 #include "intel_csr.h"
 #include "intel_dp.h"