eeprom: refactor i2c bus and devaddr parsing

Introduce parse_i2c_bus_addr() to generalize the parsing of i2c bus number and
i2c device address. This is done in preparation for merging layout aware and
layout unaware command parsing into one function.

No functional changes.

Cc: Heiko Schocher <hs@denx.de>
Cc: Marek Vasut <marex@denx.de>
Cc: Simon Glass <sjg@chromium.org>
Cc: Igor Grinberg <grinberg@compulab.co.il>
Cc: Tom Rini <trini@konsulko.com>
Signed-off-by: Nikita Kiryanov <nikita@compulab.co.il>

cmd/eeprom.c

@@ -207,6 +207,56 @@ int eeprom_write(unsigned dev_addr, unsigned offset,
 	return ret;
 }
 
+static int parse_numeric_param(char *str)
+{
+	char *endptr;
+	int value = simple_strtol(str, &endptr, 16);
+
+	return (*endptr != '\0') ? -1 : value;
+}
+
+/**
+ * parse_i2c_bus_addr - parse the i2c bus and i2c devaddr parameters
+ *
+ * @i2c_bus:	address to store the i2c bus
+ * @i2c_addr:	address to store the device i2c address
+ * @argc:	count of command line arguments left to parse
+ * @argv:	command line arguments left to parse
+ * @argc_no_bus_addr:	argc value we expect to see when bus & addr aren't given
+ *
+ * @returns:	number of arguments parsed or CMD_RET_USAGE if error
+ */
+static int parse_i2c_bus_addr(int *i2c_bus, ulong *i2c_addr, int argc,
+			      char * const argv[], int argc_no_bus_addr)
+{
+	int argc_no_bus = argc_no_bus_addr + 1;
+	int argc_bus_addr = argc_no_bus_addr + 2;
+
+#ifdef CONFIG_SYS_DEF_EEPROM_ADDR
+	if (argc == argc_no_bus_addr) {
+		*i2c_bus = -1;
+		*i2c_addr = CONFIG_SYS_DEF_EEPROM_ADDR;
+
+		return 0;
+	}
+#endif
+	if (argc == argc_no_bus) {
+		*i2c_bus = -1;
+		*i2c_addr = parse_numeric_param(argv[0]);
+
+		return 1;
+	}
+
+	if (argc == argc_bus_addr) {
+		*i2c_bus = parse_numeric_param(argv[0]);
+		*i2c_addr = parse_numeric_param(argv[1]);
+
+		return 2;
+	}
+
+	return CMD_RET_USAGE;
+}
+
 #ifdef CONFIG_CMD_EEPROM_LAYOUT
 #include <eeprom_layout.h>
 
@@ -237,14 +287,6 @@ static enum eeprom_action parse_action(char *cmd)
 	return EEPROM_ACTION_INVALID;
 }
 
-static int parse_numeric_param(char *str)
-{
-	char *endptr;
-	int value = simple_strtol(str, &endptr, 16);
-
-	return (*endptr != '\0') ? -1 : value;
-}
-
 static int eeprom_execute_command(enum eeprom_action action, int i2c_bus,
 				  int i2c_addr, int layout_ver, char *key,
 				  char *value)
@@ -348,24 +390,9 @@ static int do_eeprom(cmd_tbl_t *cmdtp, int flag, int argc, char * const argv[])
 	}
 #endif
 
-	switch (argc) {
+	rcode = parse_i2c_bus_addr(&bus_addr, &dev_addr, argc - 2, argv + 2, 3);
-#ifdef CONFIG_SYS_DEF_EEPROM_ADDR
+	if (rcode == CMD_RET_USAGE)
-	case 5:
+		return rcode;
-		bus_addr = -1;
-		dev_addr = CONFIG_SYS_DEF_EEPROM_ADDR;
-		break;
-#endif
-	case 6:
-		bus_addr = -1;
-		dev_addr = simple_strtoul(*args++, NULL, 16);
-		break;
-	case 7:
-		bus_addr = simple_strtoul(*args++, NULL, 16);
-		dev_addr = simple_strtoul(*args++, NULL, 16);
-		break;
-	default:
-		return CMD_RET_USAGE;
-	}
 
 	addr = simple_strtoul(*args++, NULL, 16);
 	off = simple_strtoul(*args++, NULL, 16);