net: phy: Allow splitting MDIO bus/device support from PHYs

Introduce a new configuration symbol: MDIO_DEVICE which allows building
the MDIO devices and bus code, without pulling in the entire Ethernet
PHY library and devices code.

PHYLIB nows select MDIO_DEVICE and the relevant Makefile files are
updated to reflect that.

When MDIO_DEVICE (MDIO bus/device only) is selected, but not PHYLIB, we
have mdio-bus.ko as a loadable module, and it does not have a
module_exit() function because the safety of removing a bus class is
unclear.

When both MDIO_DEVICE and PHYLIB are enabled, we need to assemble
everything into a common loadable module: libphy.ko because of nasty
circular dependencies between phy.c, phy_device.c and mdio_bus.c which
are really tough to untangle.

Signed-off-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

diff --git a/drivers/net/Makefile b/drivers/net/Makefile
index 98ed4d96987c87fda074a219a234cbf8e48f2b9a..55f75aea283cf72f067706c54fda4190c1c1da27 100644 (file)
--- a/drivers/net/Makefile
+++ b/drivers/net/Makefile
@@ -18,7 +18,7 @@ obj-$(CONFIG_MII) += mii.o
 obj-$(CONFIG_MDIO) += mdio.o
 obj-$(CONFIG_NET) += Space.o loopback.o
 obj-$(CONFIG_NETCONSOLE) += netconsole.o
-obj-$(CONFIG_PHYLIB) += phy/
+obj-$(CONFIG_MDIO_DEVICE) += phy/
 obj-$(CONFIG_RIONET) += rionet.o
 obj-$(CONFIG_NET_TEAM) += team/
 obj-$(CONFIG_TUN) += tun.o

diff --git a/drivers/net/phy/Kconfig b/drivers/net/phy/Kconfig
index 7ab4b14a43b73938287d66774b9ec2c0e3de85ff..60ffc9da6a286272d84e8dc3f4326eb908e7961a 100644 (file)
--- a/drivers/net/phy/Kconfig
+++ b/drivers/net/phy/Kconfig
@@ -2,33 +2,12 @@
 # PHY Layer Configuration
 #
 
-menuconfig PHYLIB
-       tristate "PHY Device support and infrastructure"
-       depends on NETDEVICES
+menuconfig MDIO_DEVICE
+       tristate "MDIO bus device drivers"
        help
-         Ethernet controllers are usually attached to PHY
-         devices.  This option provides infrastructure for
-         managing PHY devices.
-
-if PHYLIB
-
-config SWPHY
-       bool
-
-config LED_TRIGGER_PHY
-       bool "Support LED triggers for tracking link state"
-       depends on LEDS_TRIGGERS
-       ---help---
-         Adds support for a set of LED trigger events per-PHY.  Link
-         state change will trigger the events, for consumption by an
-         LED class driver.  There are triggers for each link speed currently
-         supported by the phy, and are of the form:
-              <mii bus id>:<phy>:<speed>
-
-         Where speed is in the form:
-               <Speed in megabits>Mbps or <Speed in gigabits>Gbps
+          MDIO devices and driver infrastructure code.
 
-comment "MDIO bus device drivers"
+if MDIO_DEVICE
 
 config MDIO_BCM_IPROC
        tristate "Broadcom iProc MDIO bus controller"
@@ -49,6 +28,7 @@ config MDIO_BCM_UNIMAC
 
 config MDIO_BITBANG
        tristate "Bitbanged MDIO buses"
+       depends on !(MDIO_DEVICE=y && PHYLIB=m)
        help
          This module implements the MDIO bus protocol in software,
          for use by low level drivers that export the ability to
@@ -160,6 +140,36 @@ config MDIO_XGENE
          This module provides a driver for the MDIO busses found in the
          APM X-Gene SoC's.
 
+endif
+
+menuconfig PHYLIB
+       tristate "PHY Device support and infrastructure"
+       depends on NETDEVICES
+       select MDIO_DEVICE
+       help
+         Ethernet controllers are usually attached to PHY
+         devices.  This option provides infrastructure for
+         managing PHY devices.
+
+if PHYLIB
+
+config SWPHY
+       bool
+
+config LED_TRIGGER_PHY
+       bool "Support LED triggers for tracking link state"
+       depends on LEDS_TRIGGERS
+       ---help---
+         Adds support for a set of LED trigger events per-PHY.  Link
+         state change will trigger the events, for consumption by an
+         LED class driver.  There are triggers for each link speed currently
+         supported by the phy, and are of the form:
+              <mii bus id>:<phy>:<speed>
+
+         Where speed is in the form:
+               <Speed in megabits>Mbps or <Speed in gigabits>Gbps
+
+
 comment "MII PHY device drivers"
 
 config AMD_PHY

diff --git a/drivers/net/phy/Makefile b/drivers/net/phy/Makefile
index 82d9156146468c97f22f2ea36b69ff8989b4e506..0e1ec0438c23eb334ea6e68854d0b1254b006cf1 100644 (file)
--- a/drivers/net/phy/Makefile
+++ b/drivers/net/phy/Makefile
@@ -1,7 +1,16 @@
 # Makefile for Linux PHY drivers and MDIO bus drivers
 
-libphy-y                       := phy.o phy_device.o mdio_bus.o mdio_device.o \
-                                  mdio-boardinfo.o phy-core.o
+libphy-y                       := phy.o phy-core.o phy_device.o
+mdio-bus-y                     += mdio_bus.o mdio_device.o mdio-boardinfo.o
+
+# PHYLIB implies MDIO_DEVICE, in that case, we have a bunch of circular
+# dependencies that does not make it possible to split mdio-bus objects into a
+# dedicated loadable module, so we bundle them all together into libphy.ko
+ifdef CONFIG_PHYLIB
+libphy-y                       += $(mdio-bus-y)
+else
+obj-$(CONFIG_MDIO_DEVICE)      += mdio-bus.o
+endif
 libphy-$(CONFIG_SWPHY)         += swphy.o
 libphy-$(CONFIG_LED_TRIGGER_PHY)       += phy_led_triggers.o
 

diff --git a/drivers/net/phy/mdio-boardinfo.c b/drivers/net/phy/mdio-boardinfo.c
index 6b988f77da08fca5ba9e7efec8c4af354ad51ecc..61941e29daae85abe7cc8a5726d669eae3d29137 100644 (file)
--- a/drivers/net/phy/mdio-boardinfo.c
+++ b/drivers/net/phy/mdio-boardinfo.c
@@ -84,3 +84,4 @@ int mdiobus_register_board_info(const struct mdio_board_info *info,
 
        return 0;
 }
+EXPORT_SYMBOL(mdiobus_register_board_info);

diff --git a/drivers/net/phy/mdio_bus.c b/drivers/net/phy/mdio_bus.c
index fa7d51f14869efa8b94ce161e5bd4cb96b4951d3..46b468eb6e12def44281b2b5c973427beabb93f7 100644 (file)
--- a/drivers/net/phy/mdio_bus.c
+++ b/drivers/net/phy/mdio_bus.c
@@ -648,9 +648,18 @@ int __init mdio_bus_init(void)
 
        return ret;
 }
+EXPORT_SYMBOL_GPL(mdio_bus_init);
 
+#if IS_ENABLED(CONFIG_PHYLIB)
 void mdio_bus_exit(void)
 {
        class_unregister(&mdio_bus_class);
        bus_unregister(&mdio_bus_type);
 }
+EXPORT_SYMBOL_GPL(mdio_bus_exit);
+#else
+module_init(mdio_bus_init);
+/* no module_exit, intentional */
+MODULE_LICENSE("GPL");
+MODULE_DESCRIPTION("MDIO bus/device layer");
+#endif

diff --git a/include/linux/phy.h b/include/linux/phy.h
index 2efca6b39fbad087217f78af18be061bdc46ddff..624cecf69c28d39b148b6d0616842fcf40317473 100644 (file)
--- a/include/linux/phy.h
+++ b/include/linux/phy.h
@@ -745,8 +745,24 @@ int phy_write_mmd(struct phy_device *phydev, int devad, u32 regnum, u16 val);
 struct phy_device *phy_device_create(struct mii_bus *bus, int addr, int phy_id,
                                     bool is_c45,
                                     struct phy_c45_device_ids *c45_ids);
+#if IS_ENABLED(CONFIG_PHYLIB)
 struct phy_device *get_phy_device(struct mii_bus *bus, int addr, bool is_c45);
 int phy_device_register(struct phy_device *phy);
+void phy_device_free(struct phy_device *phydev);
+#else
+static inline
+struct phy_device *get_phy_device(struct mii_bus *bus, int addr, bool is_c45)
+{
+       return NULL;
+}
+
+static inline int phy_device_register(struct phy_device *phy)
+{
+       return 0;
+}
+
+static inline void phy_device_free(struct phy_device *phydev) { }
+#endif /* CONFIG_PHYLIB */
 void phy_device_remove(struct phy_device *phydev);
 int phy_init_hw(struct phy_device *phydev);
 int phy_suspend(struct phy_device *phydev);
@@ -827,7 +843,6 @@ int phy_ethtool_ksettings_set(struct phy_device *phydev,
 int phy_mii_ioctl(struct phy_device *phydev, struct ifreq *ifr, int cmd);
 int phy_start_interrupts(struct phy_device *phydev);
 void phy_print_status(struct phy_device *phydev);
-void phy_device_free(struct phy_device *phydev);
 int phy_set_max_speed(struct phy_device *phydev, u32 max_speed);
 
 int phy_register_fixup(const char *bus_id, u32 phy_uid, u32 phy_uid_mask,
@@ -854,8 +869,10 @@ int phy_ethtool_set_link_ksettings(struct net_device *ndev,
                                   const struct ethtool_link_ksettings *cmd);
 int phy_ethtool_nway_reset(struct net_device *ndev);
 
+#if IS_ENABLED(CONFIG_PHYLIB)
 int __init mdio_bus_init(void);
 void mdio_bus_exit(void);
+#endif
 
 extern struct bus_type mdio_bus_type;
 
@@ -866,7 +883,7 @@ struct mdio_board_info {
        const void      *platform_data;
 };
 
-#if IS_ENABLED(CONFIG_PHYLIB)
+#if IS_ENABLED(CONFIG_MDIO_DEVICE)
 int mdiobus_register_board_info(const struct mdio_board_info *info,
                                unsigned int n);
 #else