env: Add a console env handler

Remove the hard-coded console handler and use a callback instead

Signed-off-by: Joe Hershberger <joe.hershberger@ni.com>

common/cmd_nvedit.c

@@ -47,7 +47,6 @@
 #include <errno.h>
 #include <malloc.h>
 #include <watchdog.h>
-#include <serial.h>
 #include <linux/stddef.h>
 #include <asm/byteorder.h>
 
@@ -206,10 +205,9 @@ static int do_env_grep(cmd_tbl_t *cmdtp, int flag,
 int env_change_ok(const ENTRY *item, const char *newval, enum env_op op,
 	int flag)
 {
-	int   console = -1;
+#ifndef CONFIG_ENV_OVERWRITE
 	const char *name;
-#if !defined(CONFIG_ENV_OVERWRITE) && defined(CONFIG_OVERWRITE_ETHADDR_ONCE) \
-&& defined(CONFIG_ETHADDR)
+#if defined(CONFIG_OVERWRITE_ETHADDR_ONCE) && defined(CONFIG_ETHADDR)
 	const char *oldval = NULL;
 
 	if (op != env_op_create)
@@ -217,35 +215,7 @@ int env_change_ok(const ENTRY *item, const char *newval, enum env_op op,
 #endif
 
 	name = item->key;
-
-	/* Default value for NULL to protect string-manipulating functions */
-	newval = newval ? : "";
-
-	/* Check for console redirection */
-	if (strcmp(name, "stdin") == 0)
-		console = stdin;
-	else if (strcmp(name, "stdout") == 0)
-		console = stdout;
-	else if (strcmp(name, "stderr") == 0)
-		console = stderr;
-
-	if (console != -1 && (gd->flags & GD_FLG_DEVINIT) != 0) {
-		if ((newval == NULL) || (*newval == '\0')) {
-			/* We cannot delete stdin/stdout/stderr */
-			if ((flag & H_FORCE) == 0)
-				printf("Can't delete \"%s\"\n", name);
-			return 1;
-		}
-
-#ifdef CONFIG_CONSOLE_MUX
-		if (iomux_doenv(console, newval))
-			return 1;
-#else
-		/* Try assigning specified device */
-		if (console_assign(console, newval) < 0)
-			return 1;
-#endif /* CONFIG_CONSOLE_MUX */
-	}
+#endif
 
 #ifndef CONFIG_ENV_OVERWRITE
 	/*

common/console.c

@@ -24,11 +24,55 @@
 #include <common.h>
 #include <stdarg.h>
 #include <malloc.h>
+#include <serial.h>
 #include <stdio_dev.h>
 #include <exports.h>
+#include <environment.h>
 
 DECLARE_GLOBAL_DATA_PTR;
 
+static int on_console(const char *name, const char *value, enum env_op op,
+	int flags)
+{
+	int console = -1;
+
+	/* Check for console redirection */
+	if (strcmp(name, "stdin") == 0)
+		console = stdin;
+	else if (strcmp(name, "stdout") == 0)
+		console = stdout;
+	else if (strcmp(name, "stderr") == 0)
+		console = stderr;
+
+	/* if not actually setting a console variable, we don't care */
+	if (console == -1 || (gd->flags & GD_FLG_DEVINIT) == 0)
+		return 0;
+
+	switch (op) {
+	case env_op_create:
+	case env_op_overwrite:
+
+#ifdef CONFIG_CONSOLE_MUX
+		if (iomux_doenv(console, value))
+			return 1;
+#else
+		/* Try assigning specified device */
+		if (console_assign(console, value) < 0)
+			return 1;
+#endif /* CONFIG_CONSOLE_MUX */
+		return 0;
+
+	case env_op_delete:
+		if ((flags & H_FORCE) == 0)
+			printf("Can't delete \"%s\"\n", name);
+		return 1;
+
+	default:
+		return 0;
+	}
+}
+U_BOOT_ENV_CALLBACK(console, on_console);
+
 #ifdef CONFIG_SYS_CONSOLE_IS_IN_ENV
 /*
  * if overwrite_console returns 1, the stdin, stderr and stdout

include/env_callback.h

@@ -42,6 +42,7 @@
 	"baudrate:baudrate," \
 	"bootfile:bootfile," \
 	"loadaddr:loadaddr," \
+	"stdin:console,stdout:console,stderr:console," \
 	CONFIG_ENV_CALLBACK_LIST_STATIC
 
 struct env_clbk_tbl {