2018-07-18 18:47 GMT+02:00 Andrew Lunn [off-list ref]:

On Wed, Jul 18, 2018 at 06:10:35PM +0200, Bartosz Golaszewski wrote:

quoted

From: Bartosz Golaszewski <redacted>

MTD doesn't support nvmem yet. Some platforms use MTD to read the MAC
address from SPI flash. If we want this function to generalize reading
the MAC address, we need to separately try to use MTD.

Signed-off-by: Bartosz Golaszewski <redacted>
---
 net/ethernet/eth.c | 20 ++++++++++++++++++++
 1 file changed, 20 insertions(+)

diff --git a/net/ethernet/eth.c b/net/ethernet/eth.c
index adf5bd03851f..f7dbd2cff7f9 100644
--- a/net/ethernet/eth.c
+++ b/net/ethernet/eth.c

@@ -55,6 +55,7 @@
 #include <linux/of_net.h>
 #include <linux/pci.h>
 #include <linux/nvmem-consumer.h>
+#include <linux/mtd/mtd.h>
 #include <net/dst.h>
 #include <net/arp.h>
 #include <net/sock.h>

@@ -573,6 +574,25 @@ int eth_platform_get_mac_address(struct device *dev, u8 *mac_addr)
              }
      }

+#ifdef CONFIG_MTD
+     /* NOTE: this should go away as soon as MTD gets nvmem support. */
+     if (!addr) {
+             struct mtd_info *mtd;
+             int rv;
+
+             mtd = get_mtd_device_nm("MAC-Address");

In order for this to go away, you need to keep backwards
compatibility. When using nvmem, you look for a cell called
"mac-address". Here you are looking for "MAC-Address". That is going
to make backwards compatibility harder. How do you plan to do it?

   Andrew

I'm trying to adjust to already existing users. The only user of
get_mtd_device_nm() who calls it to read the MAC address registers a
partition called "MAC-Address". We can't change it since it's visible
from user space. In the future we'd just have to have a list of
supported string that we'd use to do the nvmem lookup.

Bart