Commit 60495b66 authored by Vladimir Oltean's avatar Vladimir Oltean Committed by Jakub Kicinski
Browse files

net: phy: provide phylib stubs for hardware timestamping operations 



net/core/dev_ioctl.c (built-in code) will want to call phy_mii_ioctl()
for hardware timestamping purposes. This is not directly possible,
because phy_mii_ioctl() is a symbol provided under CONFIG_PHYLIB.

Do something similar to what was done in DSA in commit 5a178186
("net: dsa: replace NETDEV_PRE_CHANGE_HWTSTAMP notifier with a stub"),
and arrange some indirect calls to phy_mii_ioctl() through a stub
structure containing function pointers, that's provided by phylib as
built-in even when CONFIG_PHYLIB=m, and which phy_init() populates at
runtime (module insertion).

Note: maybe the ownership of the ethtool_phy_ops singleton is backwards,
and the methods exposed by that should be later merged into phylib_stubs.

Signed-off-by: default avatarVladimir Oltean <vladimir.oltean@nxp.com>
Link: https://lore.kernel.org/r/20230801142824.1772134-12-vladimir.oltean@nxp.com


Signed-off-by: default avatarJakub Kicinski <kuba@kernel.org>
parent 70ef7d87

MAINTAINERS

+1 −0
Original line number Diff line number Diff line
@@ -7752,6 +7752,7 @@ F: include/linux/mii.h 
F:	include/linux/of_net.h

F:	include/linux/phy.h

F:	include/linux/phy_fixed.h

F:	include/linux/phylib_stubs.h

F:	include/linux/platform_data/mdio-bcm-unimac.h

F:	include/linux/platform_data/mdio-gpio.h

F:	include/trace/events/mdio.h

drivers/net/phy/Makefile

+2 −0
Original line number Diff line number Diff line
@@ -14,6 +14,8 @@ endif 
# dedicated loadable module, so we bundle them all together into libphy.ko

ifdef CONFIG_PHYLIB

libphy-y			+= $(mdio-bus-y)

# the stubs are built-in whenever PHYLIB is built-in or module

obj-y				+= stubs.o

else

obj-$(CONFIG_MDIO_DEVICE)	+= mdio-bus.o

endif

drivers/net/phy/phy.c

+34 −0
Original line number Diff line number Diff line
@@ -455,6 +455,40 @@ int phy_do_ioctl_running(struct net_device *dev, struct ifreq *ifr, int cmd) 
}

EXPORT_SYMBOL(phy_do_ioctl_running);



/**

 * __phy_hwtstamp_get - Get hardware timestamping configuration from PHY

 *

 * @phydev: the PHY device structure

 * @config: structure holding the timestamping configuration

 *

 * Query the PHY device for its current hardware timestamping configuration.

 */

int __phy_hwtstamp_get(struct phy_device *phydev,

		       struct kernel_hwtstamp_config *config)

{

	if (!phydev)

		return -ENODEV;



	return phy_mii_ioctl(phydev, config->ifr, SIOCGHWTSTAMP);

}



/**

 * __phy_hwtstamp_set - Modify PHY hardware timestamping configuration

 *

 * @phydev: the PHY device structure

 * @config: structure holding the timestamping configuration

 * @extack: netlink extended ack structure, for error reporting

 */

int __phy_hwtstamp_set(struct phy_device *phydev,

		       struct kernel_hwtstamp_config *config,

		       struct netlink_ext_ack *extack)

{

	if (!phydev)

		return -ENODEV;



	return phy_mii_ioctl(phydev, config->ifr, SIOCSHWTSTAMP);

}



/**

 * phy_queue_state_machine - Trigger the state machine to run soon

 *

drivers/net/phy/phy_device.c

+19 −0
Original line number Diff line number Diff line
@@ -27,6 +27,7 @@ 
#include <linux/of.h>

#include <linux/netdevice.h>

#include <linux/phy.h>

#include <linux/phylib_stubs.h>

#include <linux/phy_led_triggers.h>

#include <linux/pse-pd/pse.h>

#include <linux/property.h>
@@ -3448,12 +3449,28 @@ static const struct ethtool_phy_ops phy_ethtool_phy_ops = { 
	.start_cable_test_tdr	= phy_start_cable_test_tdr,

};



static const struct phylib_stubs __phylib_stubs = {

	.hwtstamp_get = __phy_hwtstamp_get,

	.hwtstamp_set = __phy_hwtstamp_set,

};



static void phylib_register_stubs(void)

{

	phylib_stubs = &__phylib_stubs;

}



static void phylib_unregister_stubs(void)

{

	phylib_stubs = NULL;

}



static int __init phy_init(void)

{

	int rc;



	rtnl_lock();

	ethtool_set_ethtool_phy_ops(&phy_ethtool_phy_ops);

	phylib_register_stubs();

	rtnl_unlock();



	rc = mdio_bus_init();
@@ -3478,6 +3495,7 @@ static int __init phy_init(void) 
	mdio_bus_exit();

err_ethtool_phy_ops:

	rtnl_lock();

	phylib_unregister_stubs();

	ethtool_set_ethtool_phy_ops(NULL);

	rtnl_unlock();
@@ -3490,6 +3508,7 @@ static void __exit phy_exit(void) 
	phy_driver_unregister(&genphy_driver);

	mdio_bus_exit();

	rtnl_lock();

	phylib_unregister_stubs();

	ethtool_set_ethtool_phy_ops(NULL);

	rtnl_unlock();

}

drivers/net/phy/stubs.c

0 → 100644
+10 −0
Original line number Diff line number Diff line 
// SPDX-License-Identifier: GPL-2.0+

/*

 * Stubs for PHY library functionality called by the core network stack.

 * These are necessary because CONFIG_PHYLIB can be a module, and built-in

 * code cannot directly call symbols exported by modules.

 */

#include <linux/phylib_stubs.h>



const struct phylib_stubs *phylib_stubs;

EXPORT_SYMBOL_GPL(phylib_stubs);