Fix "usb part" command

Only print partition for selected device if user supplied the <dev>
arg with the "usb part [dev]" command.

Signed-off-by: Christian Eggers <ceggers@gmx.de>
Acked-by: Markus Klotzbuecher <mk@denx.de>

common/cmd_usb.c

@@ -554,8 +554,9 @@ int do_usb (cmd_tbl_t *cmdtp, int flag, int argc, char *argv[])
 	}
 
 	if (strncmp(argv[1],"part",4) == 0) {
-		int devno, ok;
-		for (ok=0, devno=0; devno<USB_MAX_STOR_DEV; ++devno) {
+		int devno, ok = 0;
+		if (argc==2) {
+			for (devno=0; devno<USB_MAX_STOR_DEV; ++devno) {
 				stor_dev=usb_stor_get_dev(devno);
 				if (stor_dev->type!=DEV_TYPE_UNKNOWN) {
 					ok++;
@@ -565,6 +566,16 @@ int do_usb (cmd_tbl_t *cmdtp, int flag, int argc, char *argv[])
 					print_part(stor_dev);
 				}
 			}
+		}
+		else {
+			devno=simple_strtoul(argv[2], NULL, 16);
+			stor_dev=usb_stor_get_dev(devno);
+			if (stor_dev->type!=DEV_TYPE_UNKNOWN) {
+				ok++;
+				printf("print_part of %x\n",devno);
+				print_part(stor_dev);
+			}
+		}
 		if (!ok) {
 			printf("\nno USB devices available\n");
 			return 1;