Add getenv_hex() to return an environment variable as hex

This conversion is required in a number of places in U-Boot. Add a
standard function to provide this feature, so we avoid all the different
variations in the way it is coded.

Signed-off-by: Simon Glass <sjg@chromium.org>

1 files changed, 13 insertions, 0 deletions

diff --git a/include/common.h b/include/common.h
index 76c79ae58e..28aa4b9d60 100644
--- a/include/common.h
+++ b/include/common.h
@@ -352,6 +352,19 @@ int	envmatch     (uchar *, int);
 char	*getenv	     (const char *);
 int	getenv_f     (const char *name, char *buf, unsigned len);
 ulong getenv_ulong(const char *name, int base, ulong default_val);
+
+/**
+ * getenv_hex() - Return an environment variable as a hex value
+ *
+ * Decode an environment as a hex number (it may or may not have a 0x
+ * prefix). If the environment variable cannot be found, or does not start
+ * with hex digits, the default value is returned.
+ *
+ * @varname:		Variable to decode
+ * @default_val:	Value to return on error
+ */
+ulong getenv_hex(const char *varname, ulong default_val);
+
 /*
  * Read an environment variable as a boolean
  * Return -1 if variable does not exist (default to true)