[PATCH 0/4] net: ethernet address helpers for board code

[PATCH 0/4] net: ethernet address helpers for board code

[Ahmad Fatoum]

Boards with switches that do MAC address assignment in barebox may want
to know which addresses were assigned and which weren't, so they can
pass through the rest to Linux userspace to be used e.g. for the bridge
ethernet address.

This adds some helpers to facilitate this. The board code making use of
this will follow seperately.

Ahmad Fatoum (4):
  net: add ethaddr sequence handling
  net: factor out eth_of_get_fixup_node
  net: export list of registered ethernet addresses
  net: implement ethaddr_string_cmp()

 include/net.h | 35 +++++++++++++++++++++++++++++++++++
 net/eth.c     | 40 +++++++++++++++++++++-------------------
 net/lib.c     | 17 +++++++++++++++++
 3 files changed, 73 insertions(+), 19 deletions(-)

-- 
2.39.5

[PATCH 1/4] net: add ethaddr sequence handling

[Ahmad Fatoum]

Instead of storing every MAC address in full, boards may elect
to store a base address and increment it N times. Add a helper
to iterate over such an Ethernet address sequence. Example usage:

  const u8 *eth_addr;
  u8 eth_base[ETH_ALEN] = "\x00\x01\x02\x03\x04\x05";
  int i = 0, eth_count = 4;

  for_each_seq_ethaddr(eth_addr, eth_base, &eth_count)
          eth_register_ethaddr(i++, eth_addr);

Signed-off-by: Ahmad Fatoum <a.fatoum@pengutronix.de>
---
 include/net.h | 12 ++++++++++++
 1 file changed, 12 insertions(+)

diff --git a/include/net.h b/include/net.h
index a04ed5b0ab92..1b6995b50043 100644
--- a/include/net.h
+++ b/include/net.h
@@ -516,6 +516,18 @@ static inline void eth_addr_add(u8 *addr, long offset)
 	u64_to_ether_addr(u, addr);
 }
 
+#define for_each_seq_ethaddr(eth_addr, eth_base, eth_count) \
+	for (eth_addr = *eth_count ? eth_base : NULL; eth_addr; eth_addr = eth_addr_seq_next(eth_base, eth_count))
+
+static inline const u8 *eth_addr_seq_next(u8 eth_base[6], unsigned *eth_count)
+{
+	if (--(*eth_count) <= 0)
+		return NULL;
+
+	eth_addr_inc(eth_base);
+	return eth_base;
+}
+
 typedef void rx_handler_f(void *ctx, char *packet, unsigned int len);
 
 struct eth_device *eth_get_byname(const char *name);
-- 
2.39.5

[PATCH 2/4] net: factor out eth_of_get_fixup_node

[Ahmad Fatoum]

We only know at fixup time, which MAC addresses were actually assigned
to interfaces. Factor out eth_of_get_fixup_node from the MAC address
assignment code, so board code can use this to retrace which MAC
addresses would be fixed up.

Signed-off-by: Ahmad Fatoum <a.fatoum@pengutronix.de>
---
 include/net.h | 12 ++++++++++++
 net/eth.c     | 29 +++++++++++++++++++----------
 2 files changed, 31 insertions(+), 10 deletions(-)

diff --git a/include/net.h b/include/net.h
index 1b6995b50043..4d4996c720ef 100644
--- a/include/net.h
+++ b/include/net.h
@@ -128,6 +128,18 @@ static inline void of_eth_register_ethaddr(struct device_node *node,
 void eth_register_ethaddr(int ethid, const char *ethaddr);
 void of_eth_register_ethaddr(struct device_node *node, const char *ethaddr);
 #endif
+
+#ifdef CONFIG_OFTREE
+struct device_node *eth_of_get_fixup_node(struct device_node *root,
+					  const char *node_path, int ethid);
+#else
+static inline struct device_node *eth_of_get_fixup_node(struct device_node *root,
+							const char *node_path, int ethid)
+{
+	return NULL;
+}
+#endif
+
 /*
  *	Ethernet header
  */
diff --git a/net/eth.c b/net/eth.c
index 7229530c055b..a1d6860be830 100644
--- a/net/eth.c
+++ b/net/eth.c
@@ -319,19 +319,11 @@ static int eth_param_set_ethaddr(struct param_d *param, void *priv)
 }
 
 #ifdef CONFIG_OFTREE
-static void eth_of_fixup_node(struct device_node *root,
-			      const char *node_path, int ethid,
-			      const u8 ethaddr[ETH_ALEN])
+struct device_node *eth_of_get_fixup_node(struct device_node *root,
+					  const char *node_path, int ethid)
 {
 	struct device_node *bb_node, *fixup_node;
 	char *name;
-	int ret;
-
-	if (!is_valid_ether_addr(ethaddr)) {
-		pr_debug("%s: no valid mac address, cannot fixup\n",
-			 __func__);
-		return;
-	}
 
 	if (node_path) {
 		bb_node = of_find_node_by_path_from(0, node_path);
@@ -344,6 +336,23 @@ static void eth_of_fixup_node(struct device_node *root,
 		fixup_node = of_find_node_by_alias(root, eth);
 	}
 
+	return fixup_node;
+}
+
+static void eth_of_fixup_node(struct device_node *root,
+			      const char *node_path, int ethid,
+			      const u8 ethaddr[ETH_ALEN])
+{
+	struct device_node *fixup_node;
+	int ret;
+
+	if (!is_valid_ether_addr(ethaddr)) {
+		pr_debug("%s: no valid mac address, cannot fixup\n",
+			 __func__);
+		return;
+	}
+
+	fixup_node = eth_of_get_fixup_node(root, node_path, ethid);
 	if (!fixup_node) {
 		pr_debug("%s: no node to fixup\n", __func__);
 		return;
-- 
2.39.5

[PATCH 3/4] net: export list of registered ethernet addresses

[Ahmad Fatoum]

Network stack keeps an ethaddr_list of Ethernet addresses that were
registered by drivers and board code.

The list currently lacks ethernet devices for which a net_device already
existed. If a net_device is added later on, the list is consulted, but
the element is not removed.

This means ethaddr_list is "the list of registered Ethernet addresses
that were added before the relevant device has been probed". Make it more
useful by genericising it to be "the list of registered Ethernet addresses".

This introduces no functional change (only consumer is fixup code that
handles both cases already), but it allows future board code to consult
the list to check which Ethernet addresses were actually assigned.

Signed-off-by: Ahmad Fatoum <a.fatoum@pengutronix.de>
---
 include/net.h |  9 +++++++++
 net/eth.c     | 11 ++---------
 2 files changed, 11 insertions(+), 9 deletions(-)

diff --git a/include/net.h b/include/net.h
index 4d4996c720ef..d9b7953a3c33 100644
--- a/include/net.h
+++ b/include/net.h
@@ -625,4 +625,13 @@ void ifdown_all(void);
 
 extern struct class eth_class;
 
+struct eth_ethaddr {
+	struct list_head list;
+	u8 ethaddr[ETH_ALEN];
+	int ethid;
+	struct device_node *node;
+};
+
+extern struct list_head ethaddr_list;
+
 #endif /* __NET_H__ */
diff --git a/net/eth.c b/net/eth.c
index a1d6860be830..3714dde44026 100644
--- a/net/eth.c
+++ b/net/eth.c
@@ -23,14 +23,7 @@
 
 DEFINE_DEV_CLASS(eth_class, "eth");
 
-struct eth_ethaddr {
-	struct list_head list;
-	u8 ethaddr[ETH_ALEN];
-	int ethid;
-	struct device_node *node;
-};
-
-static LIST_HEAD(ethaddr_list);
+LIST_HEAD(ethaddr_list);
 
 int eth_set_promisc(struct eth_device *edev, bool enable)
 {
@@ -102,7 +95,7 @@ void eth_register_ethaddr(int ethid, const char *ethaddr)
 	for_each_netdev(edev) {
 		if (edev->dev.id == ethid) {
 			register_preset_mac_address(edev, ethaddr);
-			return;
+			break;
 		}
 	}
 
-- 
2.39.5

[PATCH 4/4] net: implement ethaddr_string_cmp()

[Ahmad Fatoum]

We keep ethernet addresses either in binary or in text form at a couple
of places, e.g. device tree, device parameters, struct net_device,
... etc. We have memcmp() and strcmp() respectively to compare each, add
one more function to compare a text string with binary. This will be
used in a follow up commit.

Signed-off-by: Ahmad Fatoum <a.fatoum@pengutronix.de>
---
 include/net.h |  2 ++
 net/lib.c     | 17 +++++++++++++++++
 2 files changed, 19 insertions(+)

diff --git a/include/net.h b/include/net.h
index d9b7953a3c33..dbc45b806a51 100644
--- a/include/net.h
+++ b/include/net.h
@@ -366,6 +366,8 @@ IPaddr_t getenv_ip(const char *name);
 int setenv_ip(const char *name, IPaddr_t ip);
 
 int string_to_ethaddr(const char *str, u8 enetaddr[6]);
+void ethaddr_to_string(const u8 enetaddr[6], char *str);
+int ethaddr_string_cmp(const u8 enetaddr_a[6], const char *str_b);
 
 #ifdef CONFIG_NET_RESOLV
 int resolv(const char *host, IPaddr_t *ip);
diff --git a/net/lib.c b/net/lib.c
index dc6e138f392c..59bd4c280caf 100644
--- a/net/lib.c
+++ b/net/lib.c
@@ -37,6 +37,23 @@ int string_to_ethaddr(const char *str, u8 enetaddr[ETH_ALEN])
 	return 0;
 }
 
+void ethaddr_to_string(const u8 enetaddr[ETH_ALEN], char *str)
+{
+	sprintf(str, "%02x:%02x:%02x:%02x:%02x:%02x",
+		 enetaddr[0], enetaddr[1], enetaddr[2], enetaddr[3],
+		 enetaddr[4], enetaddr[5]);
+}
+
+int ethaddr_string_cmp(const u8 enetaddr_a[ETH_ALEN], const char *str_b)
+{
+	u8 enetaddr_b[ETH_ALEN];
+
+	if (string_to_ethaddr(str_b, enetaddr_b))
+		return -EINVAL;
+
+	return memcmp(enetaddr_a, enetaddr_b, ETH_ALEN);
+}
+
 int string_to_ip(const char *s, IPaddr_t *ip)
 {
 	IPaddr_t addr = 0;
-- 
2.39.5

Re: [PATCH 1/4] net: add ethaddr sequence handling

[Sascha Hauer]

On Tue, Nov 26, 2024 at 04:17:41PM +0100, Ahmad Fatoum wrote:
> Instead of storing every MAC address in full, boards may elect
> to store a base address and increment it N times. Add a helper
> to iterate over such an Ethernet address sequence. Example usage:
> 
>   const u8 *eth_addr;
>   u8 eth_base[ETH_ALEN] = "\x00\x01\x02\x03\x04\x05";
>   int i = 0, eth_count = 4;
> 
>   for_each_seq_ethaddr(eth_addr, eth_base, &eth_count)
>           eth_register_ethaddr(i++, eth_addr);

	for (i = 0; i < 4; i++, eth_addr_inc(eth_addr))
		eth_register_ethaddr(i, eth_addr);

I think the open coded variant is easier to read and write, I don't
think we should introduce a helper for this.

Sascha

> 
> Signed-off-by: Ahmad Fatoum <a.fatoum@pengutronix.de>
> ---
>  include/net.h | 12 ++++++++++++
>  1 file changed, 12 insertions(+)
> 
> diff --git a/include/net.h b/include/net.h
> index a04ed5b0ab92..1b6995b50043 100644
> --- a/include/net.h
> +++ b/include/net.h
> @@ -516,6 +516,18 @@ static inline void eth_addr_add(u8 *addr, long offset)
>  	u64_to_ether_addr(u, addr);
>  }
>  
> +#define for_each_seq_ethaddr(eth_addr, eth_base, eth_count) \
> +	for (eth_addr = *eth_count ? eth_base : NULL; eth_addr; eth_addr = eth_addr_seq_next(eth_base, eth_count))
> +
> +static inline const u8 *eth_addr_seq_next(u8 eth_base[6], unsigned *eth_count)
> +{
> +	if (--(*eth_count) <= 0)
> +		return NULL;
> +
> +	eth_addr_inc(eth_base);
> +	return eth_base;
> +}
> +
>  typedef void rx_handler_f(void *ctx, char *packet, unsigned int len);
>  
>  struct eth_device *eth_get_byname(const char *name);
> -- 
> 2.39.5
> 
> 
> 

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Re: [PATCH 1/4] net: add ethaddr sequence handling

[Ahmad Fatoum]

On 28.11.24 08:28, Sascha Hauer wrote:
> On Tue, Nov 26, 2024 at 04:17:41PM +0100, Ahmad Fatoum wrote:
>> Instead of storing every MAC address in full, boards may elect
>> to store a base address and increment it N times. Add a helper
>> to iterate over such an Ethernet address sequence. Example usage:
>>
>>   const u8 *eth_addr;
>>   u8 eth_base[ETH_ALEN] = "\x00\x01\x02\x03\x04\x05";
>>   int i = 0, eth_count = 4;
>>
>>   for_each_seq_ethaddr(eth_addr, eth_base, &eth_count)
>>           eth_register_ethaddr(i++, eth_addr);
> 
> 	for (i = 0; i < 4; i++, eth_addr_inc(eth_addr))
> 		eth_register_ethaddr(i, eth_addr);
> 
> I think the open coded variant is easier to read and write, I don't
> think we should introduce a helper for this.

Fair enough. The patch predates the introduction of eth_addr_inc.

Please drop this one patch.

Thanks,
Ahmad

> 
> Sascha
> 
>>
>> Signed-off-by: Ahmad Fatoum <a.fatoum@pengutronix.de>
>> ---
>>  include/net.h | 12 ++++++++++++
>>  1 file changed, 12 insertions(+)
>>
>> diff --git a/include/net.h b/include/net.h
>> index a04ed5b0ab92..1b6995b50043 100644
>> --- a/include/net.h
>> +++ b/include/net.h
>> @@ -516,6 +516,18 @@ static inline void eth_addr_add(u8 *addr, long offset)
>>  	u64_to_ether_addr(u, addr);
>>  }
>>  
>> +#define for_each_seq_ethaddr(eth_addr, eth_base, eth_count) \
>> +	for (eth_addr = *eth_count ? eth_base : NULL; eth_addr; eth_addr = eth_addr_seq_next(eth_base, eth_count))
>> +
>> +static inline const u8 *eth_addr_seq_next(u8 eth_base[6], unsigned *eth_count)
>> +{
>> +	if (--(*eth_count) <= 0)
>> +		return NULL;
>> +
>> +	eth_addr_inc(eth_base);
>> +	return eth_base;
>> +}
>> +
>>  typedef void rx_handler_f(void *ctx, char *packet, unsigned int len);
>>  
>>  struct eth_device *eth_get_byname(const char *name);
>> -- 
>> 2.39.5
>>
>>
>>
> 


-- 
Pengutronix e.K.                           |                             |
Steuerwalder Str. 21                       | http://www.pengutronix.de/  |
31137 Hildesheim, Germany                  | Phone: +49-5121-206917-0    |
Amtsgericht Hildesheim, HRA 2686           | Fax:   +49-5121-206917-5555 |

Re: [PATCH 4/4] net: implement ethaddr_string_cmp()

[Sascha Hauer]

On Tue, Nov 26, 2024 at 04:17:44PM +0100, Ahmad Fatoum wrote:
> We keep ethernet addresses either in binary or in text form at a couple
> of places, e.g. device tree, device parameters, struct net_device,
> ... etc. We have memcmp() and strcmp() respectively to compare each, add
> one more function to compare a text string with binary. This will be
> used in a follow up commit.
> 
> Signed-off-by: Ahmad Fatoum <a.fatoum@pengutronix.de>
> ---
>  include/net.h |  2 ++
>  net/lib.c     | 17 +++++++++++++++++
>  2 files changed, 19 insertions(+)
> 
> diff --git a/include/net.h b/include/net.h
> index d9b7953a3c33..dbc45b806a51 100644
> --- a/include/net.h
> +++ b/include/net.h
> @@ -366,6 +366,8 @@ IPaddr_t getenv_ip(const char *name);
>  int setenv_ip(const char *name, IPaddr_t ip);
>  
>  int string_to_ethaddr(const char *str, u8 enetaddr[6]);
> +void ethaddr_to_string(const u8 enetaddr[6], char *str);
> +int ethaddr_string_cmp(const u8 enetaddr_a[6], const char *str_b);
>  
>  #ifdef CONFIG_NET_RESOLV
>  int resolv(const char *host, IPaddr_t *ip);
> diff --git a/net/lib.c b/net/lib.c
> index dc6e138f392c..59bd4c280caf 100644
> --- a/net/lib.c
> +++ b/net/lib.c
> @@ -37,6 +37,23 @@ int string_to_ethaddr(const char *str, u8 enetaddr[ETH_ALEN])
>  	return 0;
>  }
>  
> +void ethaddr_to_string(const u8 enetaddr[ETH_ALEN], char *str)
> +{
> +	sprintf(str, "%02x:%02x:%02x:%02x:%02x:%02x",
> +		 enetaddr[0], enetaddr[1], enetaddr[2], enetaddr[3],
> +		 enetaddr[4], enetaddr[5]);
> +}

Do you reintroduce this function on purpose or due to rebasing
conflicts? A MAC address can now be printed with "%pM".

Sascha

-- 
Pengutronix e.K.                           |                             |
Steuerwalder Str. 21                       | http://www.pengutronix.de/  |
31137 Hildesheim, Germany                  | Phone: +49-5121-206917-0    |
Amtsgericht Hildesheim, HRA 2686           | Fax:   +49-5121-206917-5555 |

Re: [PATCH 4/4] net: implement ethaddr_string_cmp()

[Ahmad Fatoum]

On 28.11.24 08:36, Sascha Hauer wrote:
> On Tue, Nov 26, 2024 at 04:17:44PM +0100, Ahmad Fatoum wrote:
>> We keep ethernet addresses either in binary or in text form at a couple
>> of places, e.g. device tree, device parameters, struct net_device,
>> ... etc. We have memcmp() and strcmp() respectively to compare each, add
>> one more function to compare a text string with binary. This will be
>> used in a follow up commit.
>>
>> Signed-off-by: Ahmad Fatoum <a.fatoum@pengutronix.de>
>> ---
>>  include/net.h |  2 ++
>>  net/lib.c     | 17 +++++++++++++++++
>>  2 files changed, 19 insertions(+)
>>
>> diff --git a/include/net.h b/include/net.h
>> index d9b7953a3c33..dbc45b806a51 100644
>> --- a/include/net.h
>> +++ b/include/net.h
>> @@ -366,6 +366,8 @@ IPaddr_t getenv_ip(const char *name);
>>  int setenv_ip(const char *name, IPaddr_t ip);
>>  
>>  int string_to_ethaddr(const char *str, u8 enetaddr[6]);
>> +void ethaddr_to_string(const u8 enetaddr[6], char *str);
>> +int ethaddr_string_cmp(const u8 enetaddr_a[6], const char *str_b);
>>  
>>  #ifdef CONFIG_NET_RESOLV
>>  int resolv(const char *host, IPaddr_t *ip);
>> diff --git a/net/lib.c b/net/lib.c
>> index dc6e138f392c..59bd4c280caf 100644
>> --- a/net/lib.c
>> +++ b/net/lib.c
>> @@ -37,6 +37,23 @@ int string_to_ethaddr(const char *str, u8 enetaddr[ETH_ALEN])
>>  	return 0;
>>  }
>>  
>> +void ethaddr_to_string(const u8 enetaddr[ETH_ALEN], char *str)
>> +{
>> +	sprintf(str, "%02x:%02x:%02x:%02x:%02x:%02x",
>> +		 enetaddr[0], enetaddr[1], enetaddr[2], enetaddr[3],
>> +		 enetaddr[4], enetaddr[5]);
>> +}
> 
> Do you reintroduce this function on purpose or due to rebasing
> conflicts? A MAC address can now be printed with "%pM".

I wanted to avoid the CONFIG_PRINTF_HEXSTR dependency.

> 
> Sascha
> 


-- 
Pengutronix e.K.                           |                             |
Steuerwalder Str. 21                       | http://www.pengutronix.de/  |
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Amtsgericht Hildesheim, HRA 2686           | Fax:   +49-5121-206917-5555 |

Re: [PATCH 4/4] net: implement ethaddr_string_cmp()

[Sascha Hauer]

On Thu, Nov 28, 2024 at 08:43:12AM +0100, Ahmad Fatoum wrote:
> On 28.11.24 08:36, Sascha Hauer wrote:
> > On Tue, Nov 26, 2024 at 04:17:44PM +0100, Ahmad Fatoum wrote:
> >> We keep ethernet addresses either in binary or in text form at a couple
> >> of places, e.g. device tree, device parameters, struct net_device,
> >> ... etc. We have memcmp() and strcmp() respectively to compare each, add
> >> one more function to compare a text string with binary. This will be
> >> used in a follow up commit.
> >>
> >> Signed-off-by: Ahmad Fatoum <a.fatoum@pengutronix.de>
> >> ---
> >>  include/net.h |  2 ++
> >>  net/lib.c     | 17 +++++++++++++++++
> >>  2 files changed, 19 insertions(+)
> >>
> >> diff --git a/include/net.h b/include/net.h
> >> index d9b7953a3c33..dbc45b806a51 100644
> >> --- a/include/net.h
> >> +++ b/include/net.h
> >> @@ -366,6 +366,8 @@ IPaddr_t getenv_ip(const char *name);
> >>  int setenv_ip(const char *name, IPaddr_t ip);
> >>  
> >>  int string_to_ethaddr(const char *str, u8 enetaddr[6]);
> >> +void ethaddr_to_string(const u8 enetaddr[6], char *str);
> >> +int ethaddr_string_cmp(const u8 enetaddr_a[6], const char *str_b);
> >>  
> >>  #ifdef CONFIG_NET_RESOLV
> >>  int resolv(const char *host, IPaddr_t *ip);
> >> diff --git a/net/lib.c b/net/lib.c
> >> index dc6e138f392c..59bd4c280caf 100644
> >> --- a/net/lib.c
> >> +++ b/net/lib.c
> >> @@ -37,6 +37,23 @@ int string_to_ethaddr(const char *str, u8 enetaddr[ETH_ALEN])
> >>  	return 0;
> >>  }
> >>  
> >> +void ethaddr_to_string(const u8 enetaddr[ETH_ALEN], char *str)
> >> +{
> >> +	sprintf(str, "%02x:%02x:%02x:%02x:%02x:%02x",
> >> +		 enetaddr[0], enetaddr[1], enetaddr[2], enetaddr[3],
> >> +		 enetaddr[4], enetaddr[5]);
> >> +}
> > 
> > Do you reintroduce this function on purpose or due to rebasing
> > conflicts? A MAC address can now be printed with "%pM".
> 
> I wanted to avoid the CONFIG_PRINTF_HEXSTR dependency.

CONFIG_PRINTF_HEXSTR is for printing hexdumps using printf.
MAC address printing is compiled in unconditionally (and must be,
because the ethernet code is using it).

Sascha

-- 
Pengutronix e.K.                           |                             |
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Re: [PATCH 4/4] net: implement ethaddr_string_cmp()

[Ahmad Fatoum]

Hello Sascha,

On 28.11.24 08:52, Sascha Hauer wrote:
> On Thu, Nov 28, 2024 at 08:43:12AM +0100, Ahmad Fatoum wrote:
>> On 28.11.24 08:36, Sascha Hauer wrote:
>>> On Tue, Nov 26, 2024 at 04:17:44PM +0100, Ahmad Fatoum wrote:
>>>> We keep ethernet addresses either in binary or in text form at a couple
>>>> of places, e.g. device tree, device parameters, struct net_device,
>>>> ... etc. We have memcmp() and strcmp() respectively to compare each, add
>>>> one more function to compare a text string with binary. This will be
>>>> used in a follow up commit.
>>>>
>>>> Signed-off-by: Ahmad Fatoum <a.fatoum@pengutronix.de>
>>>> ---
>>>>  include/net.h |  2 ++
>>>>  net/lib.c     | 17 +++++++++++++++++
>>>>  2 files changed, 19 insertions(+)
>>>>
>>>> diff --git a/include/net.h b/include/net.h
>>>> index d9b7953a3c33..dbc45b806a51 100644
>>>> --- a/include/net.h
>>>> +++ b/include/net.h
>>>> @@ -366,6 +366,8 @@ IPaddr_t getenv_ip(const char *name);
>>>>  int setenv_ip(const char *name, IPaddr_t ip);
>>>>  
>>>>  int string_to_ethaddr(const char *str, u8 enetaddr[6]);
>>>> +void ethaddr_to_string(const u8 enetaddr[6], char *str);
>>>> +int ethaddr_string_cmp(const u8 enetaddr_a[6], const char *str_b);
>>>>  
>>>>  #ifdef CONFIG_NET_RESOLV
>>>>  int resolv(const char *host, IPaddr_t *ip);
>>>> diff --git a/net/lib.c b/net/lib.c
>>>> index dc6e138f392c..59bd4c280caf 100644
>>>> --- a/net/lib.c
>>>> +++ b/net/lib.c
>>>> @@ -37,6 +37,23 @@ int string_to_ethaddr(const char *str, u8 enetaddr[ETH_ALEN])
>>>>  	return 0;
>>>>  }
>>>>  
>>>> +void ethaddr_to_string(const u8 enetaddr[ETH_ALEN], char *str)
>>>> +{
>>>> +	sprintf(str, "%02x:%02x:%02x:%02x:%02x:%02x",
>>>> +		 enetaddr[0], enetaddr[1], enetaddr[2], enetaddr[3],
>>>> +		 enetaddr[4], enetaddr[5]);
>>>> +}
>>>
>>> Do you reintroduce this function on purpose or due to rebasing
>>> conflicts? A MAC address can now be printed with "%pM".
>>
>> I wanted to avoid the CONFIG_PRINTF_HEXSTR dependency.
> 
> CONFIG_PRINTF_HEXSTR is for printing hexdumps using printf.
> MAC address printing is compiled in unconditionally (and must be,
> because the ethernet code is using it).

Seems I conflated this with %*phC, I will send a v2. Thanks

> 
> Sascha
> 


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