Index: current/cdl/usbs_serial.cdl
===================================================================
--- current/cdl/usbs_serial.cdl	12 Jul 2008 10:30:34 -0000	1.1
+++ current/cdl/usbs_serial.cdl	21 Oct 2008 15:29:19 -0000
@@ -191,6 +191,31 @@
                 is first plugged into the host."
     }
 
+    cdl_option CYGBLD_IO_USB_SLAVE_SERIAL_BUSPOWERED {
+        display       "The Device is bus powered"
+        default_value 0
+        flavor        bool
+        description   "
+            Tells the driver whether the Device is a bus powered
+            device or a self powered device."
+    }
+    cdl_option CYGNUM_IO_USB_SLAVE_SERIAL_CURRENTDRAW {
+        display       "Maximum current (in mA) drawn from USB bus"
+        flavor        data
+        default_value 100
+        legal_values  1 to 500
+        requires      ((CYGNUM_IO_USB_SLAVE_SERIAL_CURRENTDRAW > 100) implies CYGBLD_IO_USB_SLAVE_SERIAL_BUSPOWERED)
+        description   "
+            The maximum current drawn by the Device from the USB bus.
+            It should report the peak value. A self powered device
+            can draw up to 100mA, a bus powered device can draw up to
+            500mA. (If it is sometimes below 100mA and sometimes over,
+            then a tranition could be done at runtime between self and
+            bus powered modes, but that would be complicated and the
+            device would have to return from configured to addressed
+            state. For details, see the USB specification.)"
+    }
+
     cdl_option  CYGBLD_IO_USB_SLAVE_SERIAL_DEBUG {
         display       "Enable debug output from the driver"
         default_value 0



Index: current/src/usbs_serial.c
===================================================================
--- current/src/usbs_serial.c	12 Jul 2008 10:30:34 -0000	1.1
+++ current/src/usbs_serial.c	21 Oct 2008 15:19:00 -0000
@@ -126,9 +126,13 @@
     number_interfaces:  USBS_SERIAL_NUM_IFACE,
     configuration_id:   1,
     configuration_str:  0,
+#ifdef CYGBLD_IO_USB_SLAVE_SERIAL_BUSPOWERED
+    attributes:         (USB_CONFIGURATION_DESCRIPTOR_ATTR_REQUIRED),
+#else
     attributes:         (USB_CONFIGURATION_DESCRIPTOR_ATTR_REQUIRED |
                          USB_CONFIGURATION_DESCRIPTOR_ATTR_SELF_POWERED),
-    max_power:          50
+#endif
+    max_power:          (CYGNUM_IO_USB_SLAVE_SERIAL_CURRENTDRAW+1)/2	//round up
 };
 
 // ----- Interface Descriptor -----