diff --git a/include/linux/dynamic_debug.h b/include/linux/dynamic_debug.h
index dce631e678dd..42cfb37d4870 100644
--- a/include/linux/dynamic_debug.h
+++ b/include/linux/dynamic_debug.h
@@ -52,6 +52,7 @@ struct _ddebug {
 } __attribute__((aligned(8)));
 
 
+struct kernel_param;
 
 #if defined(CONFIG_DYNAMIC_DEBUG_CORE)
 
@@ -181,6 +182,9 @@ void __dynamic_ibdev_dbg(struct _ddebug *descriptor,
 				   KERN_DEBUG, prefix_str, prefix_type,	\
 				   rowsize, groupsize, buf, len, ascii)
 
+int param_set_dyndbg(const char *instr, const struct kernel_param *kp);
+int param_get_dyndbg(char *buffer, const struct kernel_param *kp);
+
 #else /* !CONFIG_DYNAMIC_DEBUG_CORE */
 
 #include <linux/string.h>
@@ -227,6 +231,52 @@ static inline int dynamic_debug_exec_queries(const char *query, const char *modn
 	return 0;
 }
 
+static inline int param_set_dyndbg(const char *instr, const struct kernel_param *kp)
+{ return 0; }
+static inline int param_get_dyndbg(char *buffer, const struct kernel_param *kp)
+{ return 0; }
+
 #endif /* !CONFIG_DYNAMIC_DEBUG_CORE */
 
+struct dyndbg_bitdesc {
+	/* bitpos is inferred from index in containing array */
+	const char *prefix;
+	const char *help;
+};
+
+#if defined(CONFIG_DYNAMIC_DEBUG) || \
+	(defined(CONFIG_DYNAMIC_DEBUG_CORE) && defined(DYNAMIC_DEBUG_MODULE))
+/**
+ * DEFINE_DYNAMIC_DEBUG_CATEGORIES() - define debug categories, bitmap, sysfs-knob
+ * @fsname: parameter basename under /sys
+ * @var:    C-identifier holding state
+ * @_desc:  string summarizing the controls provided
+ * @...:    list of struct dyndbg_bitdesc initializations
+ *
+ * Defines /sys/modules/$modname/parameters/@fsname, and @bit_descs,
+ * which maps bits 0-N to categories of pr_debugs to be controlled.
+ * This is effectively write only, because controlled callsites can be
+ * further modified via >control.
+ *
+ * Also calls MODULE_PARM_DESC(fsname, _desc), with the intent to
+ * generate the bit_legend and apply it to the given bit_descs
+ */
+#define DEFINE_DYNAMIC_DEBUG_CATEGORIES(fsname, var, _desc, ...)	\
+	MODULE_PARM_DESC(fsname, _desc);				\
+	static struct dyndbg_bitdesc const dyndbg_cats_##fsname[] =	\
+		{ __VA_ARGS__, { NULL, NULL } };			\
+	module_param_cbd(fsname, &param_ops_dyndbg, &var, 0644,		\
+			 &dyndbg_cats_##fsname);
+
+#define _DD_cat_(pfx)		{ .prefix = pfx, .help = "help for " pfx }
+#define _DD_cat_help_(pfx)	"\t   " pfx "\t- help for " pfx "\n"
+
+extern const struct kernel_param_ops param_ops_dyndbg;
+#else
+#define DEFINE_DYNAMIC_DEBUG_CATEGORIES(fsname, var, bitmap_desc, ...) \
+	MODULE_PARM_DESC(fsname, "auto: " bitmap_desc);
+#define _DD_cat_(pfx)
+#define _DD_cat_help_(pfx)
+#endif
+
 #endif
diff --git a/lib/dynamic_debug.c b/lib/dynamic_debug.c
index cb5abb42c16a..6bc645a663e7 100644
--- a/lib/dynamic_debug.c
+++ b/lib/dynamic_debug.c
@@ -529,7 +529,7 @@ static int ddebug_exec_queries(char *query, const char *modname)
 		if (!query || !*query || *query == '#')
 			continue;
 
-		vpr_info("query %d: \"%s\"\n", i, query);
+		vpr_info("query %d: \"%s\" %s\n", i, query, (modname) ? modname : "");
 
 		rc = ddebug_exec_query(query, modname);
 		if (rc < 0) {
@@ -1154,3 +1154,63 @@ early_initcall(dynamic_debug_init);
 
 /* Debugfs setup must be done later */
 fs_initcall(dynamic_debug_init_control);
+
+#include <linux/moduleparam.h>
+
+#define OUR_QUERY_SIZE 128 /* typically need <40 */
+
+/**
+ * param_set_dyndbg() - drm.debug style bitmap to format-prefix categories
+ * @instr: string echo>d to sysfs
+ * @kp:    struct kernel_param* ->data has bitmap
+ * Exported to support DEFINE_DYNAMIC_DEBUG_CATEGORIES
+ */
+int param_set_dyndbg(const char *instr, const struct kernel_param *kp)
+{
+	unsigned long inbits;
+	int rc, i, chgct = 0, totct = 0;
+	char query[OUR_QUERY_SIZE];
+	struct dyndbg_bitdesc *bitmap = (struct dyndbg_bitdesc *) kp->data;
+
+	rc = kstrtoul(instr, 0, &inbits);
+	if (rc) {
+		pr_err("set_dyndbg: failed\n");
+		return -EINVAL;
+	}
+	vpr_info("set_dyndbg: input 0x%lx\n", inbits);
+
+	for (i = 0; !!bitmap[i].prefix; i++) {
+
+		sprintf(query, "format '^%s' %cp", bitmap[i].prefix,
+			test_bit(i, &inbits) ? '+' : '-');
+
+		chgct = dynamic_debug_exec_queries(query, kp->mod->name);
+
+		v2pr_info("bit-%d: %d changes by '%s'\n", i, chgct, query);
+		totct += chgct;
+	}
+	vpr_info("total changes: %d\n", totct);
+	return 0;
+}
+EXPORT_SYMBOL(param_set_dyndbg);
+
+/**
+ * param_get_dyndbg() - drm.debug style bitmap to format-prefix categories
+ * @buffer: string returned to user via sysfs
+ * @kp:     struct kernel_param*
+ * Exported to support DEFINE_DYNAMIC_DEBUG_CATEGORIES interfaces, not
+ * useful; pr_debugs may be altered after setting via >control
+ */
+int param_get_dyndbg(char *buffer, const struct kernel_param *kp)
+{
+	return scnprintf(buffer, PAGE_SIZE, "%u\n",
+			 *((unsigned int *)kp->arg));
+}
+EXPORT_SYMBOL(param_get_dyndbg);
+
+const struct kernel_param_ops param_ops_dyndbg = {
+	.set = param_set_dyndbg,
+	.get = param_get_dyndbg,
+};
+/* support DEFINE_DYNAMIC_DEBUG_CATEGORIES users */
+EXPORT_SYMBOL(param_ops_dyndbg);
