dyndbg's CLASSMAP-v1 api was broken; DECLARE_DYNDBG_CLASSMAP tried to
do too much.  Its replaced by DYNAMIC_DEBUG_CLASSMAP_DEFINE which
creates & EXPORTs a classmap, and DYNAMIC_DEBUG_CLASSMAP_USE which
refers to that exported classmap, creating a module dependency.  DRM
gets DRM_CLASSMAP_* wrappers to hide the DRM_USE_DYNAMIC_DEBUG ifdef.

The drivers still use DECLARE_DYNDBG_CLASSMAP for now, so they still
redundantly re-declare the classmap, but we can convert the drivers
later to DYNDBG_CLASSMAP_USE, at which point they'll respond to the
echo class FOO >control commands.

Signed-off-by: Jim Cromie <jim.cromie@gmail.com>
Reviewed-by: Louis Chauvet <louis.chauvet@bootlin.com>
---
this ignored a checkpatch
 WARNING: Argument 'name' is not used in function-like macro
 #70: FILE: include/drm/drm_print.h:148:
 +#define DRM_CLASSMAP_USE(name)

the macro is empty, and correct. only 1 arg is expected.

v++: fix old CLASSBITS/CLASSMAP comment
---
 drivers/gpu/drm/drm_print.c | 25 +++++++++++++------------
 include/drm/drm_print.h     | 13 ++++++++++++-
 2 files changed, 25 insertions(+), 13 deletions(-)

diff --git a/drivers/gpu/drm/drm_print.c b/drivers/gpu/drm/drm_print.c
index 9b622345e2eb..c0ec866f31dd 100644
--- a/drivers/gpu/drm/drm_print.c
+++ b/drivers/gpu/drm/drm_print.c
@@ -56,18 +56,19 @@ MODULE_PARM_DESC(debug, "Enable debug output, where each bit enables a debug cat
 #if !defined(CONFIG_DRM_USE_DYNAMIC_DEBUG)
 module_param_named(debug, __drm_debug, ulong, 0600);
 #else
-/* classnames must match vals of enum drm_debug_category */
-DECLARE_DYNDBG_CLASSMAP(drm_debug_classes, DD_CLASS_TYPE_DISJOINT_BITS, 0,
-			"DRM_UT_CORE",
-			"DRM_UT_DRIVER",
-			"DRM_UT_KMS",
-			"DRM_UT_PRIME",
-			"DRM_UT_ATOMIC",
-			"DRM_UT_VBL",
-			"DRM_UT_STATE",
-			"DRM_UT_LEASE",
-			"DRM_UT_DP",
-			"DRM_UT_DRMRES");
+/* classnames must match value-symbols of enum drm_debug_category */
+DRM_CLASSMAP_DEFINE(drm_debug_classes, DD_CLASS_TYPE_DISJOINT_BITS,
+		    DRM_UT_CORE,
+		    "DRM_UT_CORE",
+		    "DRM_UT_DRIVER",
+		    "DRM_UT_KMS",
+		    "DRM_UT_PRIME",
+		    "DRM_UT_ATOMIC",
+		    "DRM_UT_VBL",
+		    "DRM_UT_STATE",
+		    "DRM_UT_LEASE",
+		    "DRM_UT_DP",
+		    "DRM_UT_DRMRES");
 
 static struct ddebug_class_param drm_debug_bitmap = {
 	.bits = &__drm_debug,
diff --git a/include/drm/drm_print.h b/include/drm/drm_print.h
index ab017b05e175..b743ee3f8f5e 100644
--- a/include/drm/drm_print.h
+++ b/include/drm/drm_print.h
@@ -96,7 +96,10 @@ extern unsigned long __drm_debug;
  *
  */
 enum drm_debug_category {
-	/* These names must match those in DYNAMIC_DEBUG_CLASSBITS */
+	/*
+	 * These enum-names are reused in DRM_CLASSMAP_DEFINE to
+	 * expose them as classes in /proc/dynamic_debug/control
+	 */
 	/**
 	 * @DRM_UT_CORE: Used in the generic drm code: drm_ioctl.c, drm_mm.c,
 	 * drm_memory.c, ...
@@ -141,6 +144,14 @@ enum drm_debug_category {
 	DRM_UT_DRMRES
 };
 
+#ifdef CONFIG_DRM_USE_DYNAMIC_DEBUG
+#define DRM_CLASSMAP_DEFINE(...)    DYNAMIC_DEBUG_CLASSMAP_DEFINE(__VA_ARGS__)
+#define DRM_CLASSMAP_USE(name)      DYNAMIC_DEBUG_CLASSMAP_USE(name)
+#else
+#define DRM_CLASSMAP_DEFINE(...)
+#define DRM_CLASSMAP_USE(name)
+#endif
+
 static inline bool drm_debug_enabled_raw(enum drm_debug_category category)
 {
 	return unlikely(__drm_debug & BIT(category));
-- 
2.53.0