[U-Boot] [PATCH v2] net/eth.c: fix eth_write_hwaddr() to use dev->enetaddr as fall back

[Dirk Behme]

From: Eric Miao <eric.miao at linaro.org>

Ignore the return value of eth_getenv_enetaddr_by_index(), and if it
fails, fall back to use dev->enetaddr, which could be filled up by
the ethernet device driver:

With the current code, introduced with below commit, eth_write_hwaddr()
will fail immediately if there is no eth<n>addr in the environment variables.

However, e.g. for an overo based product that uses the SMSC911x ethernet
chip (with the MAC address set via EEPROM connected to the SMSC911x chip),
the MAC address is still OK.

On mx28 boards that are depending on the OCOTP bits to set the MAC address
(like the Denx m28 board), the OCOTP bits should be used instead of
failing on the environment variables.

Actually, this was the original behavior, and was later changed by
commit 7616e7850804c7c69e0a22c179dfcba9e8f3f587.

Signed-off-by: Eric Miao <eric.miao at linaro.org>
Acked-by: Simon Glass <sjg at chromium.org>
Acked-by: Dirk Behme <dirk.behme at de.bosch.com>
CC: Stefan Roese <sr at denx.de>
CC: Eric Miao <eric.miao at linaro.org>
CC: Wolfgang Denk <wd at denx.de>
CC: Philip Balister <philip at balister.org>
CC: Zach Sadecki <zach at itwatchdogs.com>
---
v2: Correct the referenced commit ID and update the commit message.
    No functional change at the code itself.

Note: This resend is based on my understanding from

      http://lists.denx.de/pipermail/u-boot/2012-January/116118.html

      Please let Eric and me know if I missed anything there.

 net/eth.c |    3 +--
 1 files changed, 1 insertions(+), 2 deletions(-)

diff --git a/net/eth.c b/net/eth.c
index b4b9b43..451568f 100644
--- a/net/eth.c
+++ b/net/eth.c
@@ -175,8 +175,7 @@ int eth_write_hwaddr(struct eth_device *dev, const char *base_name,
 	unsigned char env_enetaddr[6];
 	int ret = 0;
 
-	if (!eth_getenv_enetaddr_by_index(base_name, eth_number, env_enetaddr))
-		return -1;
+	eth_getenv_enetaddr_by_index(base_name, eth_number, env_enetaddr);
 
 	if (memcmp(env_enetaddr, "\0\0\0\0\0\0", 6)) {
 		if (memcmp(dev->enetaddr, "\0\0\0\0\0\0", 6) &&
-- 
1.7.0.4