[PATCH RESUBMIT net-next] net: phy: factor out legacy PHY fixup support and make it always built-in
From: Heiner Kallweit <hkallweit1@gmail.com>
Date: 2026-09-13 20:00:07
Subsystem:
ethernet phy library, networking drivers, the rest · Maintainers:
Andrew Lunn, Heiner Kallweit, Andrew Lunn, "David S. Miller", Eric Dumazet, Jakub Kicinski, Paolo Abeni, Linus Torvalds
PHY fixup registration is used from platform code in init phase only. Let's move the PHY fixup code from the modular part of phylib to the always built-in part of phylib. This allows to annotate the fixup registration as __init. No caller uses the return code of PHY fixup registration, therefore change related functions to return void. phy_needs_fixup() and phy_scan_fixups() wouldn't have to be moved to the built-in part of phylib. But doing so allows to fully factor out legacy fixup support into its own source code file, and make struct phy_fixup and phy_fixup_list strictly private to phy_fixup.c. phy_scan_fixups() is used after init phase only, then phy_fixup_list is read-only. So we don't need the mutex when accessing the list. Also when registering PHY fixups the mutex isn't needed, because fixup registration is done sequentially from platform init code. Actually there is only one platform with more than one fixup. In addition this change lays the foundation for enabling modular phylib on platforms where the fixup just sets a flag. Signed-off-by: Heiner Kallweit <hkallweit1@gmail.com> --- This is a resubmit from Jan 2026. The change depends on removal of the dnet driver, and at that time the dnet driver had just been removed, with a certain risk that this removal has to be reverted. --- drivers/net/phy/Makefile | 2 +- drivers/net/phy/phy_device.c | 90 ---------------------------- drivers/net/phy/phy_fixup.c | 99 +++++++++++++++++++++++++++++++ drivers/net/phy/phylib-internal.h | 1 + include/linux/phy.h | 8 +-- 5 files changed, 105 insertions(+), 95 deletions(-) create mode 100644 drivers/net/phy/phy_fixup.c
diff --git a/drivers/net/phy/Makefile b/drivers/net/phy/Makefile
index e23df5e836e..4674eaf243e 100644
--- a/drivers/net/phy/Makefile
+++ b/drivers/net/phy/Makefile@@ -8,7 +8,7 @@ libphy-y := phy.o phy-c45.o phy-core.o phy_device.o \ ifdef CONFIG_PHYLIB # built-in whenever PHYLIB is built-in or module -obj-y += stubs.o +obj-y += stubs.o phy_fixup.o endif libphy-$(CONFIG_SWPHY) += swphy.o
diff --git a/drivers/net/phy/phy_device.c b/drivers/net/phy/phy_device.c
index 94b2e85e00a..27c0cb13860 100644
--- a/drivers/net/phy/phy_device.c
+++ b/drivers/net/phy/phy_device.c@@ -49,14 +49,6 @@ MODULE_DESCRIPTION("PHY library"); MODULE_AUTHOR("Andy Fleming"); MODULE_LICENSE("GPL"); -struct phy_fixup { - struct list_head list; - char bus_id[MII_BUS_ID_SIZE + 3]; - u32 phy_uid; - u32 phy_uid_mask; - int (*run)(struct phy_device *phydev); -}; - static struct phy_driver genphy_c45_driver = { .phy_id = 0xffffffff, .phy_id_mask = 0xffffffff,
@@ -237,9 +229,6 @@ static void phy_mdio_device_remove(struct mdio_device *mdiodev) static struct phy_driver genphy_driver; -static LIST_HEAD(phy_fixup_list); -static DEFINE_MUTEX(phy_fixup_lock); - static bool phy_drv_wol_enabled(struct phy_device *phydev) { struct ethtool_wolinfo wol = { .cmd = ETHTOOL_GWOL };
@@ -427,85 +416,6 @@ static __maybe_unused int mdio_bus_phy_resume(struct device *dev) static SIMPLE_DEV_PM_OPS(mdio_bus_phy_pm_ops, mdio_bus_phy_suspend, mdio_bus_phy_resume); -/** - * phy_register_fixup - creates a new phy_fixup and adds it to the list - * @bus_id: A string which matches phydev->mdio.dev.bus_id (or NULL) - * @phy_uid: Used to match against phydev->phy_id (the UID of the PHY) - * @phy_uid_mask: Applied to phydev->phy_id and fixup->phy_uid before - * comparison (or 0 to disable id-based matching) - * @run: The actual code to be run when a matching PHY is found - */ -static int phy_register_fixup(const char *bus_id, u32 phy_uid, u32 phy_uid_mask, - int (*run)(struct phy_device *)) -{ - struct phy_fixup *fixup = kzalloc_obj(*fixup); - - if (!fixup) - return -ENOMEM; - - if (bus_id) - strscpy(fixup->bus_id, bus_id, sizeof(fixup->bus_id)); - fixup->phy_uid = phy_uid; - fixup->phy_uid_mask = phy_uid_mask; - fixup->run = run; - - mutex_lock(&phy_fixup_lock); - list_add_tail(&fixup->list, &phy_fixup_list); - mutex_unlock(&phy_fixup_lock); - - return 0; -} - -/* Registers a fixup to be run on any PHY with the UID in phy_uid */ -int phy_register_fixup_for_uid(u32 phy_uid, u32 phy_uid_mask, - int (*run)(struct phy_device *)) -{ - return phy_register_fixup(NULL, phy_uid, phy_uid_mask, run); -} -EXPORT_SYMBOL(phy_register_fixup_for_uid); - -/* Registers a fixup to be run on the PHY with id string bus_id */ -int phy_register_fixup_for_id(const char *bus_id, - int (*run)(struct phy_device *)) -{ - return phy_register_fixup(bus_id, 0, 0, run); -} -EXPORT_SYMBOL(phy_register_fixup_for_id); - -static bool phy_needs_fixup(struct phy_device *phydev, struct phy_fixup *fixup) -{ - if (!strcmp(fixup->bus_id, phydev_name(phydev))) - return true; - - if (fixup->phy_uid_mask && - phy_id_compare(phydev->phy_id, fixup->phy_uid, fixup->phy_uid_mask)) - return true; - - return false; -} - -/* Runs any matching fixups for this phydev */ -static int phy_scan_fixups(struct phy_device *phydev) -{ - struct phy_fixup *fixup; - - mutex_lock(&phy_fixup_lock); - list_for_each_entry(fixup, &phy_fixup_list, list) { - if (phy_needs_fixup(phydev, fixup)) { - int err = fixup->run(phydev); - - if (err < 0) { - mutex_unlock(&phy_fixup_lock); - return err; - } - phydev->has_fixups = true; - } - } - mutex_unlock(&phy_fixup_lock); - - return 0; -} - /** * genphy_match_phy_device - match a PHY device with a PHY driver * @phydev: target phy_device struct
diff --git a/drivers/net/phy/phy_fixup.c b/drivers/net/phy/phy_fixup.c
new file mode 100644
index 00000000000..f49fc4cefe8
--- /dev/null
+++ b/drivers/net/phy/phy_fixup.c@@ -0,0 +1,99 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +/* + * PHY fixup support + */ + +#include <linux/list.h> +#include <linux/phy.h> +#include <linux/slab.h> +#include <linux/string.h> + +#include "phylib-internal.h" + +static struct list_head phy_fixup_list __ro_after_init = + LIST_HEAD_INIT(phy_fixup_list); + +struct phy_fixup { + struct list_head list; + char bus_id[MII_BUS_ID_SIZE + 3]; + u32 phy_uid; + u32 phy_uid_mask; + int (*run)(struct phy_device *phydev); +}; + +/** + * phy_register_fixup - creates a new phy_fixup and adds it to the list + * @bus_id: A string which matches phydev->mdio.dev.bus_id (or PHY_ANY_ID) + * @phy_uid: Used to match against phydev->phy_id (the UID of the PHY) + * It can also be PHY_ANY_UID + * @phy_uid_mask: Applied to phydev->phy_id and fixup->phy_uid before + * comparison + * @run: The actual code to be run when a matching PHY is found + */ +static void __init phy_register_fixup(const char *bus_id, u32 phy_uid, + u32 phy_uid_mask, + int (*run)(struct phy_device *)) +{ + struct phy_fixup *fixup = kzalloc_obj(*fixup); + + if (!fixup) + return; + + if (bus_id) + strscpy(fixup->bus_id, bus_id); + fixup->phy_uid = phy_uid; + fixup->phy_uid_mask = phy_uid_mask; + fixup->run = run; + + list_add_tail(&fixup->list, &phy_fixup_list); +} + +/* Registers a fixup to be run on any PHY with the UID in phy_uid */ +void __init phy_register_fixup_for_uid(u32 phy_uid, u32 phy_uid_mask, + int (*run)(struct phy_device *)) +{ + phy_register_fixup(NULL, phy_uid, phy_uid_mask, run); +} + +/* Registers a fixup to be run on the PHY with id string bus_id */ +void __init phy_register_fixup_for_id(const char *bus_id, + int (*run)(struct phy_device *)) +{ + phy_register_fixup(bus_id, 0, 0, run); +} + +static bool phy_needs_fixup(struct phy_device *phydev, struct phy_fixup *fixup) +{ + if (!strcmp(fixup->bus_id, phydev_name(phydev))) + return true; + + if (fixup->phy_uid_mask && + phy_id_compare(phydev->phy_id, fixup->phy_uid, fixup->phy_uid_mask)) + return true; + + return false; +} + +/** + * phy_scan_fixups - runs any matching fixups for this phydev + * @phydev: the phydev to search and run fixups for + * Returns: 0 or an errno + */ +int phy_scan_fixups(struct phy_device *phydev) +{ + struct phy_fixup *fixup; + + list_for_each_entry(fixup, &phy_fixup_list, list) { + if (phy_needs_fixup(phydev, fixup)) { + int err = fixup->run(phydev); + + if (err < 0) + return err; + + phydev->has_fixups = true; + } + } + + return 0; +} +EXPORT_SYMBOL_GPL(phy_scan_fixups);
diff --git a/drivers/net/phy/phylib-internal.h b/drivers/net/phy/phylib-internal.h
index 664ed7faa51..38ee294f3c9 100644
--- a/drivers/net/phy/phylib-internal.h
+++ b/drivers/net/phy/phylib-internal.h@@ -23,6 +23,7 @@ void of_set_phy_eee_broken(struct phy_device *phydev); 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 phy_scan_fixups(struct phy_device *phydev); int mdiobus_register_device(struct mdio_device *mdiodev); int mdiobus_unregister_device(struct mdio_device *mdiodev);
diff --git a/include/linux/phy.h b/include/linux/phy.h
index 5f8d65868e0..f799b3684cd 100644
--- a/include/linux/phy.h
+++ b/include/linux/phy.h@@ -2422,10 +2422,10 @@ int phy_get_mac_termination(struct phy_device *phydev, struct device *dev, void phy_resolve_pause(unsigned long *local_adv, unsigned long *partner_adv, bool *tx_pause, bool *rx_pause); -int phy_register_fixup_for_id(const char *bus_id, - int (*run)(struct phy_device *)); -int phy_register_fixup_for_uid(u32 phy_uid, u32 phy_uid_mask, - int (*run)(struct phy_device *)); +void __init phy_register_fixup_for_id(const char *bus_id, + int (*run)(struct phy_device *)); +void __init phy_register_fixup_for_uid(u32 phy_uid, u32 phy_uid_mask, + int (*run)(struct phy_device *)); int phy_eee_tx_clock_stop_capable(struct phy_device *phydev); int phy_eee_rx_clock_stop(struct phy_device *phydev, bool clk_stop_enable);
--
2.55.0