[PATCH] net/smscx5xx: change to of_get_mac_address() eth_platform_get_mac_address()

[PATCH] net/smscx5xx: change to of_get_mac_address() eth_platform_get_mac_address()

[Łukasz Stelmach]

Use more generic eth_platform_get_mac_address() which can get a MAC
address from other than DT platform specific sources too. Check if the
obtained address is valid.

Signed-off-by: Łukasz Stelmach <l.stelmach@samsung.com>
---
 drivers/net/usb/smsc75xx.c | 13 +++++++------
 drivers/net/usb/smsc95xx.c | 13 +++++++------
 2 files changed, 14 insertions(+), 12 deletions(-)

diff --git a/drivers/net/usb/smsc75xx.c b/drivers/net/usb/smsc75xx.c
index 9556d431885f..8689835a5214 100644
--- a/drivers/net/usb/smsc75xx.c
+++ b/drivers/net/usb/smsc75xx.c
@@ -757,13 +757,14 @@ static int smsc75xx_ioctl(struct net_device *netdev, struct ifreq *rq, int cmd)
 
 static void smsc75xx_init_mac_address(struct usbnet *dev)
 {
-	const u8 *mac_addr;
-
 	/* maybe the boot loader passed the MAC address in devicetree */
-	mac_addr = of_get_mac_address(dev->udev->dev.of_node);
-	if (!IS_ERR(mac_addr)) {
-		ether_addr_copy(dev->net->dev_addr, mac_addr);
-		return;
+	if (!eth_platform_get_mac_address(&dev->udev->dev,
+			dev->net->dev_addr)) {
+		if (is_valid_ether_addr(dev->net->dev_addr)) {
+			/* device tree values are valid so use them */
+			netif_dbg(dev, ifup, dev->net, "MAC address read from the device tree\n");
+			return;
+		}
 	}
 
 	/* try reading mac address from EEPROM */
diff --git a/drivers/net/usb/smsc95xx.c b/drivers/net/usb/smsc95xx.c
index 601fb40a2a0a..ea0d5f04dc3a 100644
--- a/drivers/net/usb/smsc95xx.c
+++ b/drivers/net/usb/smsc95xx.c
@@ -755,13 +755,14 @@ static int smsc95xx_ioctl(struct net_device *netdev, struct ifreq *rq, int cmd)
 
 static void smsc95xx_init_mac_address(struct usbnet *dev)
 {
-	const u8 *mac_addr;
-
 	/* maybe the boot loader passed the MAC address in devicetree */
-	mac_addr = of_get_mac_address(dev->udev->dev.of_node);
-	if (!IS_ERR(mac_addr)) {
-		ether_addr_copy(dev->net->dev_addr, mac_addr);
-		return;
+	if (!eth_platform_get_mac_address(&dev->udev->dev,
+			dev->net->dev_addr)) {
+		if (is_valid_ether_addr(dev->net->dev_addr)) {
+			/* device tree values are valid so use them */
+			netif_dbg(dev, ifup, dev->net, "MAC address read from the device tree\n");
+			return;
+		}
 	}
 
 	/* try reading mac address from EEPROM */
-- 
2.26.2

Re: [PATCH] net/smscx5xx: change to of_get_mac_address() eth_platform_get_mac_address()

[David Miller]

From: Łukasz Stelmach <l.stelmach@samsung.com>
Date: Wed, 30 Sep 2020 16:25:25 +0200

> Use more generic eth_platform_get_mac_address() which can get a MAC
> address from other than DT platform specific sources too. Check if the
> obtained address is valid.
> 
> Signed-off-by: Łukasz Stelmach <l.stelmach@samsung.com>

Failure to probe a MAC address should result in the selection of a
random one.  This way, the interface still comes up and is usable
even when the MAC address fails to be probed.

Re: [PATCH] net/smscx5xx: change to of_get_mac_address() eth_platform_get_mac_address()

[Florian Fainelli]

On 10/1/2020 7:05 PM, David Miller wrote:
> From: Łukasz Stelmach <l.stelmach@samsung.com>
> Date: Wed, 30 Sep 2020 16:25:25 +0200
> 
>> Use more generic eth_platform_get_mac_address() which can get a MAC
>> address from other than DT platform specific sources too. Check if the
>> obtained address is valid.
>>
>> Signed-off-by: Łukasz Stelmach <l.stelmach@samsung.com>
> 
> Failure to probe a MAC address should result in the selection of a
> random one.  This way, the interface still comes up and is usable
> even when the MAC address fails to be probed.

True, however this behavior is not changed after this patch is applied, 
I would argue that this should be a separate patch.
-- 
Florian

Re: [PATCH] net/smscx5xx: change to of_get_mac_address() eth_platform_get_mac_address()

[Lukasz Stelmach]

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It was <2020-10-01 czw 19:45>, when Florian Fainelli wrote:
> On 10/1/2020 7:05 PM, David Miller wrote:
>> From: Łukasz Stelmach <l.stelmach@samsung.com>
>> Date: Wed, 30 Sep 2020 16:25:25 +0200
>>
>>> Use more generic eth_platform_get_mac_address() which can get a MAC
>>> address from other than DT platform specific sources too. Check if the
>>> obtained address is valid.
>>>
>>> Signed-off-by: Łukasz Stelmach <l.stelmach@samsung.com>
>>
>> Failure to probe a MAC address should result in the selection of a
>> random one.  This way, the interface still comes up and is usable
>> even when the MAC address fails to be probed.
>
> True, however this behavior is not changed after this patch is
> applied, I would argue that this should be a separate patch.

In both drivers the second to last line of the *_init_mac_address()[1][2]
functions is

    eth_hw_addr_random(dev->net);

and I haven't changed that. My patches enable getting a MAC address via
arch/platform specific function[3] arch_get_platform_mac_address() if
of_get_mac_address() fails.

[1] https://elixir.bootlin.com/linux/v5.8/source/drivers/net/usb/smsc75xx.c#L758
[2] https://elixir.bootlin.com/linux/v5.8/source/drivers/net/usb/smsc95xx.c#L902
[3] https://elixir.bootlin.com/linux/v5.8/source/net/ethernet/eth.c#L502
-- 
Łukasz Stelmach
Samsung R&D Institute Poland
Samsung Electronics

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Re: [PATCH] net/smscx5xx: change to of_get_mac_address() eth_platform_get_mac_address()

[David Miller]

From: Lukasz Stelmach <l.stelmach@samsung.com>
Date: Fri, 02 Oct 2020 09:39:40 +0200

> In both drivers the second to last line of the *_init_mac_address()[1][2]
> functions is
> 
>     eth_hw_addr_random(dev->net);

My bad, indeed it does take care of this already.

Applied to net-next, thanks.