Provide phylink_expects_phy() to allow MAC drivers to check if it
is expecting a PHY to attach to. Since fixed-linked setups do not
need to attach to a PHY.

Provides a boolean value as to if the MAC should expect a PHY.
returns true if a PHY is expected.

Signed-off-by: Michael Sit Wei Hong <michael.wei.hong.sit@intel.com>
---
 drivers/net/phy/phylink.c | 17 +++++++++++++++++
 include/linux/phylink.h   |  1 +
 2 files changed, 18 insertions(+)

diff --git a/drivers/net/phy/phylink.c b/drivers/net/phy/phylink.c
index 1a2f074685fa..4c080656e280 100644
--- a/drivers/net/phy/phylink.c
+++ b/drivers/net/phy/phylink.c
@@ -1586,6 +1586,23 @@ void phylink_destroy(struct phylink *pl)
 }
 EXPORT_SYMBOL_GPL(phylink_destroy);
 
+/**
+ * phylink_expects_phy() - Determine if phylink expects a phy to be attached
+ * @pl: a pointer to a &struct phylink returned from phylink_create()
+ *
+ * Fixed-link mode does not need a PHY, returns a boolean value to check if
+ * phylink will be expecting a PHY to attach.
+ */
+bool phylink_expects_phy(struct phylink *pl)
+{
+	if (pl->cfg_link_an_mode == MLO_AN_FIXED ||
+	    (pl->cfg_link_an_mode == MLO_AN_INBAND &&
+	     phy_interface_mode_is_8023z(pl->link_config.interface)))
+		return false;
+	return true;
+}
+EXPORT_SYMBOL_GPL(phylink_expects_phy);
+
 static void phylink_phy_change(struct phy_device *phydev, bool up)
 {
 	struct phylink *pl = phydev->phylink;
diff --git a/include/linux/phylink.h b/include/linux/phylink.h
index c492c26202b5..637698ed5cb6 100644
--- a/include/linux/phylink.h
+++ b/include/linux/phylink.h
@@ -574,6 +574,7 @@ struct phylink *phylink_create(struct phylink_config *, struct fwnode_handle *,
 			       phy_interface_t iface,
 			       const struct phylink_mac_ops *mac_ops);
 void phylink_destroy(struct phylink *);
+bool phylink_expects_phy(struct phylink *pl);
 
 int phylink_connect_phy(struct phylink *, struct phy_device *);
 int phylink_of_phy_connect(struct phylink *, struct device_node *, u32 flags);
-- 
2.34.1

On Thu, Mar 30, 2023 at 04:39:58PM +0800, Michael Sit Wei Hong wrote:
> Provide phylink_expects_phy() to allow MAC drivers to check if it
> is expecting a PHY to attach to. Since fixed-linked setups do not
> need to attach to a PHY.
> 
> Provides a boolean value as to if the MAC should expect a PHY.
> returns true if a PHY is expected.
> 
> Signed-off-by: Michael Sit Wei Hong <michael.wei.hong.sit@intel.com>
> ---
>  drivers/net/phy/phylink.c | 17 +++++++++++++++++
>  include/linux/phylink.h   |  1 +
>  2 files changed, 18 insertions(+)
> 
> diff --git a/drivers/net/phy/phylink.c b/drivers/net/phy/phylink.c
> index 1a2f074685fa..4c080656e280 100644
> --- a/drivers/net/phy/phylink.c
> +++ b/drivers/net/phy/phylink.c
> @@ -1586,6 +1586,23 @@ void phylink_destroy(struct phylink *pl)
>  }
>  EXPORT_SYMBOL_GPL(phylink_destroy);
>  
> +/**
> + * phylink_expects_phy() - Determine if phylink expects a phy to be attached
> + * @pl: a pointer to a &struct phylink returned from phylink_create()
> + *
> + * Fixed-link mode does not need a PHY, returns a boolean value to check if
> + * phylink will be expecting a PHY to attach.

This description could be clearer (for example, it isn't just about
fixed-link mode), but apart from that, it's good. I don't think that's
a reason to delay this any further, but please follow-up with a patch
to improve this description.

Reviewed-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk>

Thanks!

-- 
RMK's Patch system: https://www.armlinux.org.uk/developer/patches/
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