drm/print: introduce new struct drm_device based WARN* macros

Add new struct drm_device based WARN* macros. These are modeled after
the core kernel device based WARN* macros. These would be preferred
over the regular WARN* macros, where possible.

These macros include device information in the backtrace, so we know
what device the warnings originate from.

Knowing the device specific information in the backtrace would be
helpful in development all around.
Signed-off-by: Pankaj Bharadiya <pankaj.laxminarayan.bharadiya@intel.com>
Reviewed-by: Jani Nikula <jani.nikula@intel.com>
Reviewed-by: Sam Ravnborg <sam@ravnborg.org>
Acked-by: Maxime Ripard <mripard@kernel.org>
Acked-by: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Acked-by: Sean Paul <sean@poorly.run>
Signed-off-by: Jani Nikula <jani.nikula@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200115034455.17658-2-pankaj.laxminarayan.bharadiya@intel.com

include/drm/drm_print.h

@@ -553,4 +553,33 @@ void __drm_err(const char *format, ...);
 #define DRM_DEBUG_PRIME_RATELIMITED(fmt, ...)				\
 	DRM_DEV_DEBUG_PRIME_RATELIMITED(NULL, fmt, ##__VA_ARGS__)
 
+/*
+ * struct drm_device based WARNs
+ *
+ * drm_WARN*() acts like WARN*(), but with the key difference of
+ * using device specific information so that we know from which device
+ * warning is originating from.
+ *
+ * Prefer drm_device based drm_WARN* over regular WARN*
+ */
+
+/* Helper for struct drm_device based WARNs */
+#define drm_WARN(drm, condition, format, arg...)			\
+	WARN(condition, "%s %s: " format,				\
+			dev_driver_string((drm)->dev),			\
+			dev_name((drm)->dev), ## arg)
+
+#define drm_WARN_ONCE(drm, condition, format, arg...)			\
+	WARN_ONCE(condition, "%s %s: " format,				\
+			dev_driver_string((drm)->dev),			\
+			dev_name((drm)->dev), ## arg)
+
+#define drm_WARN_ON(drm, x)						\
+	drm_WARN((drm), (x), "%s",					\
+		 "drm_WARN_ON(" __stringify(x) ")")
+
+#define drm_WARN_ON_ONCE(drm, x)					\
+	drm_WARN_ONCE((drm), (x), "%s",					\
+		      "drm_WARN_ON_ONCE(" __stringify(x) ")")
+
 #endif /* DRM_PRINT_H_ */