Make "usage" messages more helpful.

In case of incorrect command invocations U-Boot used to print pretty
useless "usage" messages, for example:

	=> nand markbad
	Usage:
	nand - NAND sub-system

In the result, the user would have to run the "help" command to get
the (available) information about correct command usage. Change this,
so that this information gets always printed.

Note that this changes the user interface of all commands, but
hopefully to the better.

Signed-off-by: Wolfgang Denk <wd@denx.de>

diff --git a/common/command.c b/common/command.c
index c9a3f5bf6b51342a4972b36d66b4ad90030f9076..16f3afe3947ef608b00f78665d8974700399b2b1 100644 (file)
--- a/common/command.c
+++ b/common/command.c
@@ -286,21 +286,7 @@ int _do_help (cmd_tbl_t *cmd_start, int cmd_items, cmd_tbl_t * cmdtp, int
         */
        for (i = 1; i < argc; ++i) {
                if ((cmdtp = find_cmd_tbl (argv[i], cmd_start, cmd_items )) != NULL) {
-#ifdef CONFIG_SYS_LONGHELP
-                       /* found - print (long) help info */
-                       puts (cmdtp->name);
-                       putc (' ');
-                       if (cmdtp->help) {
-                               puts (cmdtp->help);
-                       } else {
-                               puts ("- No help available.\n");
-                               rcode = 1;
-                       }
-                       putc ('\n');
-#else  /* no long help available */
-                       if (cmdtp->usage)
-                               printf ("%s - %s\n", cmdtp->name, cmdtp->usage);
-#endif /* CONFIG_SYS_LONGHELP */
+                       rcode |= cmd_usage(cmdtp);
                } else {
                        printf ("Unknown command '%s' - try 'help'"
                                " without arguments for list of all"
@@ -386,9 +372,22 @@ cmd_tbl_t *find_cmd (const char *cmd)
        return find_cmd_tbl(cmd, &__u_boot_cmd_start, len);
 }
 
-void cmd_usage(cmd_tbl_t *cmdtp)
+int cmd_usage(cmd_tbl_t *cmdtp)
 {
-       printf("Usage:\n%s - %s\n\n", cmdtp->name, cmdtp->usage);
+       printf("%s - %s\n\n", cmdtp->name, cmdtp->usage);
+
+#ifdef CONFIG_SYS_LONGHELP
+       printf("Usage:\n%s ", cmdtp->name);
+
+       if (!cmdtp->help) {
+               puts ("- No additional help available.\n");
+               return 1;
+       }
+
+       puts (cmdtp->help);
+       putc ('\n');
+#endif /* CONFIG_SYS_LONGHELP */
+       return 0;
 }
 
 #ifdef CONFIG_AUTO_COMPLETE

diff --git a/include/command.h b/include/command.h
index bd478539250415aff2828ee432bd914d167616d6..55caa6eaf888cdb916d3937a5054ad862ec0e0ab 100644 (file)
--- a/include/command.h
+++ b/include/command.h
@@ -71,7 +71,7 @@ int _do_help (cmd_tbl_t *cmd_start, int cmd_items, cmd_tbl_t * cmdtp, int
 cmd_tbl_t *find_cmd(const char *cmd);
 cmd_tbl_t *find_cmd_tbl (const char *cmd, cmd_tbl_t *table, int table_len);
 
-extern void cmd_usage(cmd_tbl_t *cmdtp);
+extern int cmd_usage(cmd_tbl_t *cmdtp);
 
 #ifdef CONFIG_AUTO_COMPLETE
 extern void install_auto_complete(void);