eeprom: Add bus argument to eeprom_init()

Add bus argument to eeprom_init(), so that it can select
the I2C bus number on which the eeprom resides. Any negative
value of the $bus argument will preserve the old behavior.
This is in place so that old code does not randomly break.

Signed-off-by: Marek Vasut <marex@denx.de>
Cc: Simon Glass <sjg@chromium.org>
Cc: Tom Rini <trini@konsulko.com>
Cc: Heiko Schocher <hs@denx.de>
Reviewed-by: Heiko Schocher <hs@denx.de>
[trini: Wrap i2c_set_bus_num() call with CONFIG_SYS_I2C test]
Signed-off-by: Tom Rini <trini@konsulko.com>
diff --git a/common/cmd_eeprom.c b/common/cmd_eeprom.c
index d0942ef..120ddbb 100644
--- a/common/cmd_eeprom.c
+++ b/common/cmd_eeprom.c
@@ -60,7 +60,7 @@
 	return 0;
 }
 
-void eeprom_init(void)
+void eeprom_init(int bus)
 {
 	/* SPI EEPROM */
 #if defined(CONFIG_SPI) && !defined(CONFIG_ENV_EEPROM_IS_ON_I2C)
@@ -69,6 +69,10 @@
 
 	/* I2C EEPROM */
 #if defined(CONFIG_HARD_I2C) || defined(CONFIG_SYS_I2C_SOFT)
+#if defined(CONFIG_SYS_I2C)
+	if (bus >= 0)
+		i2c_set_bus_num(bus);
+#endif
 	i2c_init(CONFIG_SYS_I2C_SPEED, CONFIG_SYS_I2C_SLAVE);
 #endif
 }
@@ -223,7 +227,7 @@
 	off = simple_strtoul(*args++, NULL, 16);
 	cnt = simple_strtoul(*args++, NULL, 16);
 
-	eeprom_init();
+	eeprom_init(-1);
 
 	if (strcmp (argv[1], "read") == 0) {
 		printf(fmt, dev_addr, argv[1], addr, off, cnt);