diff --git a/litex/soc/doc/csr.py b/litex/soc/doc/csr.py
index 0b0670daa..cfc17bf6d 100644
--- a/litex/soc/doc/csr.py
+++ b/litex/soc/doc/csr.py
@@ -235,7 +235,9 @@ class DocumentedCSRRegion:
         print("", file=stream)
         print("        {", file=stream)
         print("            \"reg\": [", file=stream)
+        multilane = False
         if len(reg.fields) > 0:
+            min_field_size = self.csr_data_width
             bit_offset = 0
             for field in reg.fields:
                 field_name = field.name
@@ -254,6 +256,9 @@ class DocumentedCSRRegion:
                     term=""
                 print("                {\"name\": \"" + field_name + "\",  " + type_str + attr_str + "\"bits\": " + str(field.size) + "}" + term, file=stream)
                 bit_offset = field.offset + field.size
+                min_field_size = min(min_field_size, field.size)
+                if min_field_size < 8:
+                    multilane = True
             if bit_offset != self.busword:
                 print("                {\"bits\": " + str(self.busword - bit_offset) + "}", file=stream)
         else:
@@ -265,8 +270,12 @@ class DocumentedCSRRegion:
                 attr_str = "\"attr\": 'reset: " + str(reg.reset_value) + "', "
             print("                {\"name\": \"" + reg.short_name.lower() + self.bit_range(reg.offset, reg.offset + reg.size, empty_if_zero=True) + "\", " + attr_str + "\"bits\": " + str(reg.size) + "}" + term, file=stream)
             if reg.size != self.csr_data_width:
+                multilane = True
                 print("                {\"bits\": " + str(self.csr_data_width - reg.size) + "},", file=stream)
-        lanes = self.busword / 8
+        if multilane:
+            lanes = self.busword / 8
+        else:
+            lanes = 1
         print("            ], \"config\": {\"hspace\": 400, \"bits\": " + str(self.busword) + ", \"lanes\": " + str(lanes) + " }, \"options\": {\"hspace\": 400, \"bits\": " + str(self.busword) + ", \"lanes\": " + str(lanes) + "}", file=stream)
         print("        }", file=stream)
         print("", file=stream)