[PATCH RFC net-next v2 1/6] net: phylink: split out and export interface to caps translation

["Russell King (Oracle)" <rmk+kernel@armlinux.org.uk>]

phylink_get_linkmodes() translates the interface mode into a set of
speed and duplex capabilities which are masked with the MAC modes to
then derive the link modes that are available.

Split out the initial transformation into a new function
phylink_interface_to_caps(), and export it, which will be useful when
setting the maximum fixed link speed in DSA code.

Signed-off-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk>
---
 drivers/net/phy/phylink.c | 30 ++++++++++++++++++++++--------
 include/linux/phylink.h   |  1 +
 2 files changed, 23 insertions(+), 8 deletions(-)

diff --git a/drivers/net/phy/phylink.c b/drivers/net/phy/phylink.c
index 9bd69328dc4d..1d4a48d5a5ac 100644
--- a/drivers/net/phy/phylink.c
+++ b/drivers/net/phy/phylink.c
@@ -297,17 +297,12 @@ static void phylink_caps_to_linkmodes(unsigned long *linkmodes,
 }
 
 /**
- * phylink_get_linkmodes() - get acceptable link modes
- * @linkmodes: ethtool linkmode mask (must be already initialised)
+ * phylink_interface_to_caps() - translate an interface mode to phylink caps
  * @interface: phy interface mode defined by &typedef phy_interface_t
- * @mac_capabilities: bitmask of MAC capabilities
  *
- * Set all possible pause, speed and duplex linkmodes in @linkmodes that
- * are supported by the @interface mode and @mac_capabilities. @linkmodes
- * must have been initialised previously.
+ * Translate the @interface mode to a phylink MAC capabilities mask.
  */
-void phylink_get_linkmodes(unsigned long *linkmodes, phy_interface_t interface,
-			   unsigned long mac_capabilities)
+unsigned long phylink_interface_to_caps(phy_interface_t interface)
 {
 	unsigned long caps = MAC_SYM_PAUSE | MAC_ASYM_PAUSE;
 
@@ -381,6 +376,25 @@ void phylink_get_linkmodes(unsigned long *linkmodes, phy_interface_t interface,
 		break;
 	}
 
+	return caps;
+}
+EXPORT_SYMBOL_GPL(phylink_interface_to_caps);
+
+/**
+ * phylink_get_linkmodes() - get acceptable link modes
+ * @linkmodes: ethtool linkmode mask (must be already initialised)
+ * @interface: phy interface mode defined by &typedef phy_interface_t
+ * @mac_capabilities: bitmask of MAC capabilities
+ *
+ * Set all possible pause, speed and duplex linkmodes in @linkmodes that
+ * are supported by the @interface mode and @mac_capabilities. @linkmodes
+ * must have been initialised previously.
+ */
+void phylink_get_linkmodes(unsigned long *linkmodes, phy_interface_t interface,
+			   unsigned long mac_capabilities)
+{
+	unsigned long caps = phylink_interface_to_caps(interface);
+
 	phylink_caps_to_linkmodes(linkmodes, caps & mac_capabilities);
 }
 EXPORT_SYMBOL_GPL(phylink_get_linkmodes);
diff --git a/include/linux/phylink.h b/include/linux/phylink.h
index 6d06896fc20d..692be109a9fa 100644
--- a/include/linux/phylink.h
+++ b/include/linux/phylink.h
@@ -518,6 +518,7 @@ void pcs_link_up(struct phylink_pcs *pcs, unsigned int mode,
 		 phy_interface_t interface, int speed, int duplex);
 #endif
 
+unsigned long phylink_interface_to_caps(phy_interface_t interface);
 void phylink_get_linkmodes(unsigned long *linkmodes, phy_interface_t interface,
 			   unsigned long mac_capabilities);
 void phylink_generic_validate(struct phylink_config *config,
-- 
2.30.2