cmd: eeprom: add support for layout aware commands

Introduce the (optional) eeprom print and eeprom update commands.

These commands are eeprom layout aware:
* The eeprom print command prints the contents of the eeprom in a human
  readable way (eeprom layout fields, and data formatted to be fit for human
  consumption).
* The eeprom update command allows user to update eeprom fields by specifying
  the field name, and providing the new data in a human readable format (same
  format as displayed by the eeprom print command).
* Both commands can either auto detect the layout, or be told which layout to
  use.

New CONFIG options:
CONFIG_CMD_EEPROM_LAYOUT - enables commands.
CONFIG_EEPROM_LAYOUT_HELP_STRING - tells user what layout names are supported

Feature API:
__weak int parse_layout_version(char *str)
	- override to provide your own layout name parsing
__weak void __eeprom_layout_assign(struct eeprom_layout *layout, int layout_version);
	- override to setup the layout metadata based on the version
__weak int eeprom_layout_detect(unsigned char *data)
	- override to provide your own algorithm for detecting layout version
eeprom_field.c
	- contains various printing and updating functions for common types of
	  eeprom fields. Can be used for defining custom layouts.

Cc: Heiko Schocher <[email protected]>
Cc: Marek Vasut <[email protected]>
Cc: Simon Glass <[email protected]>
Cc: Igor Grinberg <[email protected]>
Cc: Tom Rini <[email protected]>
Signed-off-by: Nikita Kiryanov <[email protected]>

1 files changed, 33 insertions, 0 deletions

diff --git a/include/eeprom_layout.h b/include/eeprom_layout.h
new file mode 100644
index 00000000000..459b99d8618
--- /dev/null
+++ b/include/eeprom_layout.h
@@ -0,0 +1,33 @@
+/*
+ * (C) Copyright 2009-2016 CompuLab, Ltd.
+ *
+ * Authors: Nikita Kiryanov <[email protected]>
+ *	    Igor Grinberg <[email protected]>
+ *
+ * SPDX-License-Identifier:	GPL-2.0+
+ */
+
+#ifndef _LAYOUT_
+#define _LAYOUT_
+
+#define RESERVED_FIELDS			NULL
+#define LAYOUT_VERSION_UNRECOGNIZED	-1
+#define LAYOUT_VERSION_AUTODETECT	-2
+
+struct eeprom_layout {
+	struct eeprom_field *fields;
+	int num_of_fields;
+	int layout_version;
+	unsigned char *data;
+	int data_size;
+	void (*print)(const struct eeprom_layout *eeprom_layout);
+	int (*update)(struct eeprom_layout *eeprom_layout, char *field_name,
+		      char *new_data);
+};
+
+void eeprom_layout_setup(struct eeprom_layout *layout, unsigned char *buf,
+			 unsigned int buf_size, int layout_version);
+__weak void __eeprom_layout_assign(struct eeprom_layout *layout,
+				   int layout_version);
+
+#endif