net: phy: make mdio_device.c part of libphy

This patch
- makes mdio_device.c part of libphy
- makes mdio_device_(un)register_reset() static
- moves mdiobus_(un)register_device() from mdio_bus.c to mdio_device.c,
  stops exporting both functions and makes them private to phylib

This further decouples the MDIO consumer functionality from libphy.

Note: This makes MDIO driver registration part of phylib, therefore
      adjust Kconfig dependencies where needed.

Signed-off-by: Heiner Kallweit <hkallweit1@gmail.com>
Link: https://patch.msgid.link/c6dbf9b3-3ca0-434b-ad3a-71fe602ab809@gmail.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

drivers/clk/qcom/Kconfig

@@ -392,7 +392,7 @@ config IPQ_NSSCC_9574
 
 config IPQ_NSSCC_QCA8K
 	tristate "QCA8K(QCA8386 or QCA8084) NSS Clock Controller"
-	depends on MDIO_BUS
+	depends on PHYLIB
 	help
 	  Support for NSS(Network SubSystem) clock controller on
 	  qca8386/qca8084 chip.

drivers/net/phy/Makefile

@@ -3,8 +3,8 @@
 
 libphy-y			:= phy.o phy-c45.o phy-core.o phy_device.o \
 				   linkmode.o phy_link_topology.o \
-				   phy_caps.o mdio_bus_provider.o phy_port.o
-mdio-bus-y			+= mdio_bus.o mdio_device.o
+				   phy_caps.o mdio_bus_provider.o phy_port.o \
+				   mdio_device.o
 
 ifdef CONFIG_PHYLIB
 # built-in whenever PHYLIB is built-in or module
@@ -15,7 +15,7 @@ libphy-$(CONFIG_SWPHY)		+= swphy.o
 libphy-$(CONFIG_LED_TRIGGER_PHY)	+= phy_led_triggers.o
 libphy-$(CONFIG_OPEN_ALLIANCE_HELPERS) += open_alliance_helpers.o
 
-obj-$(CONFIG_MDIO_BUS)		+= mdio-bus.o
+obj-$(CONFIG_MDIO_BUS)		+= mdio_bus.o
 obj-$(CONFIG_PHYLINK)		+= phylink.o
 obj-$(CONFIG_PHYLIB)		+= libphy.o
 obj-$(CONFIG_PHYLIB)		+= mdio_devres.o

drivers/net/phy/mdio-private.h

@@ -1,11 +0,0 @@
-/* SPDX-License-Identifier: GPL-2.0-or-later */
-#ifndef __MDIO_PRIVATE_H
-#define __MDIO_PRIVATE_H
-
-/* MDIO internal helpers
- */
-
-int mdio_device_register_reset(struct mdio_device *mdiodev);
-void mdio_device_unregister_reset(struct mdio_device *mdiodev);
-
-#endif /* __MDIO_PRIVATE_H */

drivers/net/phy/mdio_bus.c

@@ -29,46 +29,10 @@
 #include <linux/string.h>
 #include <linux/uaccess.h>
 #include <linux/unistd.h>
-#include "mdio-private.h"
 
 #define CREATE_TRACE_POINTS
 #include <trace/events/mdio.h>
 
-int mdiobus_register_device(struct mdio_device *mdiodev)
-{
-	int err;
-
-	if (mdiodev->bus->mdio_map[mdiodev->addr])
-		return -EBUSY;
-
-	if (mdiodev->flags & MDIO_DEVICE_FLAG_PHY) {
-		err = mdio_device_register_reset(mdiodev);
-		if (err)
-			return err;
-
-		/* Assert the reset signal */
-		mdio_device_reset(mdiodev, 1);
-	}
-
-	mdiodev->bus->mdio_map[mdiodev->addr] = mdiodev;
-
-	return 0;
-}
-EXPORT_SYMBOL(mdiobus_register_device);
-
-int mdiobus_unregister_device(struct mdio_device *mdiodev)
-{
-	if (mdiodev->bus->mdio_map[mdiodev->addr] != mdiodev)
-		return -EINVAL;
-
-	mdio_device_unregister_reset(mdiodev);
-
-	mdiodev->bus->mdio_map[mdiodev->addr] = NULL;
-
-	return 0;
-}
-EXPORT_SYMBOL(mdiobus_unregister_device);
-
 static struct mdio_device *mdiobus_find_device(struct mii_bus *bus, int addr)
 {
 	bool addr_valid = addr >= 0 && addr < ARRAY_SIZE(bus->mdio_map);

drivers/net/phy/mdio_device.c

@@ -22,7 +22,7 @@
 #include <linux/string.h>
 #include <linux/unistd.h>
 #include <linux/property.h>
-#include "mdio-private.h"
+#include "phylib-internal.h"
 
 /**
  * mdio_device_register_reset - Read and initialize the reset properties of
@@ -31,7 +31,7 @@
  *
  * Return: Zero if successful, negative error code on failure
  */
-int mdio_device_register_reset(struct mdio_device *mdiodev)
+static int mdio_device_register_reset(struct mdio_device *mdiodev)
 {
 	struct reset_control *reset;
 
@@ -67,7 +67,7 @@ int mdio_device_register_reset(struct mdio_device *mdiodev)
  *				  an mdio device
  * @mdiodev: mdio_device structure
  */
-void mdio_device_unregister_reset(struct mdio_device *mdiodev)
+static void mdio_device_unregister_reset(struct mdio_device *mdiodev)
 {
 	gpiod_put(mdiodev->reset_gpio);
 	mdiodev->reset_gpio = NULL;
@@ -189,6 +189,39 @@ void mdio_device_remove(struct mdio_device *mdiodev)
 }
 EXPORT_SYMBOL(mdio_device_remove);
 
+int mdiobus_register_device(struct mdio_device *mdiodev)
+{
+	int err;
+
+	if (mdiodev->bus->mdio_map[mdiodev->addr])
+		return -EBUSY;
+
+	if (mdiodev->flags & MDIO_DEVICE_FLAG_PHY) {
+		err = mdio_device_register_reset(mdiodev);
+		if (err)
+			return err;
+
+		/* Assert the reset signal */
+		mdio_device_reset(mdiodev, 1);
+	}
+
+	mdiodev->bus->mdio_map[mdiodev->addr] = mdiodev;
+
+	return 0;
+}
+
+int mdiobus_unregister_device(struct mdio_device *mdiodev)
+{
+	if (mdiodev->bus->mdio_map[mdiodev->addr] != mdiodev)
+		return -EINVAL;
+
+	mdio_device_unregister_reset(mdiodev);
+
+	mdiodev->bus->mdio_map[mdiodev->addr] = NULL;
+
+	return 0;
+}
+
 /**
  * mdio_probe - probe an MDIO device
  * @dev: device to probe

drivers/net/phy/phylib-internal.h

@@ -6,6 +6,7 @@
 #ifndef __PHYLIB_INTERNAL_H
 #define __PHYLIB_INTERNAL_H
 
+struct mdio_device;
 struct phy_device;
 
 /*
@@ -20,6 +21,9 @@ void of_set_phy_timing_role(struct phy_device *phydev);
 int phy_speed_down_core(struct phy_device *phydev);
 void phy_check_downshift(struct phy_device *phydev);
 
+int mdiobus_register_device(struct mdio_device *mdiodev);
+int mdiobus_unregister_device(struct mdio_device *mdiodev);
+
 int genphy_c45_read_eee_adv(struct phy_device *phydev, unsigned long *adv);
 
 #endif /* __PHYLIB_INTERNAL_H */

drivers/phy/broadcom/Kconfig

@@ -52,7 +52,7 @@ config PHY_BCM_NS_USB3
 	tristate "Broadcom Northstar USB 3.0 PHY Driver"
 	depends on ARCH_BCM_IPROC || COMPILE_TEST
 	depends on HAS_IOMEM && OF
-	depends on MDIO_BUS
+	depends on PHYLIB
 	select GENERIC_PHY
 	help
 	  Enable this to support Broadcom USB 3.0 PHY connected to the USB
@@ -60,7 +60,7 @@ config PHY_BCM_NS_USB3
 
 config PHY_NS2_PCIE
 	tristate "Broadcom Northstar2 PCIe PHY driver"
-	depends on (OF && MDIO_BUS_MUX_BCM_IPROC) || (COMPILE_TEST && MDIO_BUS)
+	depends on (OF && MDIO_BUS_MUX_BCM_IPROC) || (COMPILE_TEST && PHYLIB)
 	select GENERIC_PHY
 	default ARCH_BCM_IPROC
 	help

include/linux/mdio.h

@@ -688,8 +688,6 @@ static inline int mdiodev_c45_write(struct mdio_device *mdiodev, u32 devad,
 				 val);
 }
 
-int mdiobus_register_device(struct mdio_device *mdiodev);
-int mdiobus_unregister_device(struct mdio_device *mdiodev);
 bool mdiobus_is_registered_device(struct mii_bus *bus, int addr);
 struct phy_device *mdiobus_get_phy(struct mii_bus *bus, int addr);