[PATCH RESEND] net: mii: Fix the Speed display when the network cable is not connected

[PATCH RESEND] net: mii: Fix the Speed display when the network cable is not connected

[Xiangqian Zhang]

Speed should be SPEED_UNKNOWN when the network cable is not connected

Signed-off-by: Xiangqian Zhang <zhangxiangqian@kylinos.cn>
---
 drivers/net/mii.c | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/drivers/net/mii.c b/drivers/net/mii.c
index 22680f47385d..297a0cc3682f 100644
--- a/drivers/net/mii.c
+++ b/drivers/net/mii.c
@@ -213,6 +213,9 @@ void mii_ethtool_get_link_ksettings(struct mii_if_info *mii,
 		lp_advertising = 0;
 	}
 
+	if (!mii_link_ok(mii))
+		cmd->base.speed = SPEED_UNKNOWN;
+
 	mii->full_duplex = cmd->base.duplex;
 
 	ethtool_convert_legacy_u32_to_link_mode(cmd->link_modes.supported,
-- 
2.25.1

Re: [PATCH RESEND] net: mii: Fix the Speed display when the network cable is not connected

[Andrew Lunn]

On Fri, Jan 10, 2025 at 05:23:02PM +0800, Xiangqian Zhang wrote:
> Speed should be SPEED_UNKNOWN when the network cable is not connected

What driver is actually using this? Have you really experienced this
problem? The mii_ code is really old, i doubt there are too many
drivers in use today which use it. So a bit more explanation would be
good.

    Andrew

---
pw-bot: cr

[PATCH v2] net: mii: Fix the Speed display when the network cable is not connected

[Xiangqian Zhang]

Two different models of usb card, the drivers are r8152 and asix. If no
network cable is connected, Speed = 10Mb/s. This problem is repeated in
linux 3.10, 4.19, and 5.4. Both drivers call
mii_ethtool_get_link_ksettings, but the value of cmd->base.speed in this
function can only be SPEED_1000 or SPEED_100 or SPEED_10.
When the network cable is not connected, set cmd->base.speed
=SPEED_UNKNOWN.

Signed-off-by: Xiangqian Zhang <zhangxiangqian@kylinos.cn>
---
 drivers/net/mii.c | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/drivers/net/mii.c b/drivers/net/mii.c
index 22680f47385d..297a0cc3682f 100644
--- a/drivers/net/mii.c
+++ b/drivers/net/mii.c
@@ -213,6 +213,9 @@ void mii_ethtool_get_link_ksettings(struct mii_if_info *mii,
 		lp_advertising = 0;
 	}
 
+	if (!mii_link_ok(mii))
+		cmd->base.speed = SPEED_UNKNOWN;
+
 	mii->full_duplex = cmd->base.duplex;
 
 	ethtool_convert_legacy_u32_to_link_mode(cmd->link_modes.supported,
-- 
2.25.1

Re: [PATCH v2] net: mii: Fix the Speed display when the network cable is not connected

[Jakub Kicinski]

On Sat, 11 Jan 2025 21:22:42 +0800 Xiangqian Zhang wrote:
> Two different models of usb card, the drivers are r8152 and asix. If no
> network cable is connected, Speed = 10Mb/s. This problem is repeated in
> linux 3.10, 4.19, and 5.4. Both drivers call
> mii_ethtool_get_link_ksettings, but the value of cmd->base.speed in this
> function can only be SPEED_1000 or SPEED_100 or SPEED_10.
> When the network cable is not connected, set cmd->base.speed
> =SPEED_UNKNOWN.
> 
> Signed-off-by: Xiangqian Zhang <zhangxiangqian@kylinos.cn>
> ---
>  drivers/net/mii.c | 3 +++
>  1 file changed, 3 insertions(+)
> 
> diff --git a/drivers/net/mii.c b/drivers/net/mii.c
> index 22680f47385d..297a0cc3682f 100644
> --- a/drivers/net/mii.c
> +++ b/drivers/net/mii.c
> @@ -213,6 +213,9 @@ void mii_ethtool_get_link_ksettings(struct mii_if_info *mii,
>  		lp_advertising = 0;
>  	}
>  
> +	if (!mii_link_ok(mii))
> +		cmd->base.speed = SPEED_UNKNOWN;

Maybe you could use the already read value of bmsr?

	if (!(bmsr & BMSR_LSTATUS))
		cmd->base.speed = SPEED_UNKNOWN;

When you post a v3 please added a link to v2:

---
v2: https://lore.kernel.org/20250111132242.3327654-1-zhangxiangqian@kylinos.cn

but do *not* post it in reply to this thread.
-- 
pw-bot: cr