Re: [PATCH v4 01/10] of_net: add NVMEM support to of_get_mac_address

Maxime Ripard [off-list ref] [2019-05-03 16:36:43]:

Hi,

...

quoted

+	pp = devm_kzalloc(&pdev->dev, sizeof(*pp), GFP_KERNEL);
+	if (!pp)
+		return ERR_PTR(-ENOMEM);
+
+	pp->name = "nvmem-mac-address";
+	pp->length = ETH_ALEN;
+	pp->value = devm_kmemdup(&pdev->dev, mac, ETH_ALEN, GFP_KERNEL);
+	if (!pp->value) {
+		ret = -ENOMEM;
+		goto free;
+	}
+
+	ret = of_add_property(np, pp);
+	if (ret)
+		goto free;
+
+	return pp->value;

I'm not sure why you need to do that allocation here, and why you need
to modify the DT?

I was asked about that in v2[0] already, so just copy&pasting relevant part of
my response here:

 I've just carried it over from v1 ("of_net: add mtd-mac-address support to
 of_get_mac_address()")[1] as nobody objected about this so far.

 Honestly I don't know if it's necessary to have it, but so far address,
 mac-address and local-mac-address properties provide this DT nodes, so I've
 simply thought, that it would be good to have it for MAC address from NVMEM as
 well in order to stay consistent.

 [...]

0. https://patchwork.ozlabs.org/patch/1092248/#2164089
1. https://patchwork.ozlabs.org/patch/1086628/

can't you just return the mac address directly since it's what the
of_get_mac_address caller will expect anyway?

I don't need this stuff, I can remove it, please just tell me what is
appropriate and I'm going to do that.

-- ynezz