Reset properties of an `mdio_device` are initialized in multiple source files and multiple functions: - `reset_assert_delay` and `reset_deassert_delay` are in fwnode_mdio.c - `reset_gpio` and `reset_ctrl` are in mdio_bus.c, but handled by different functions This patch unifies the handling of all these properties into two functions. mdiobus_register_gpiod() and mdiobus_register_reset() are removed, while mdio_device_register_reset() and mdio_device_unregister_reset() are introduced instead. These functions handle both reset-controllers and reset-gpios, and also read the corresponding properties from the device tree. These changes should make tracking the reset properties easier. The reset logic is unaltered, and should work as it did before. Signed-off-by: Buday Csaba --- V1 -> V2: the return value of mdio_device_unregister_reset() is made void --- drivers/net/mdio/fwnode_mdio.c | 5 ---- drivers/net/phy/mdio_bus.c | 39 ++------------------------ drivers/net/phy/mdio_device.c | 50 ++++++++++++++++++++++++++++++++++ include/linux/mdio.h | 2 ++ 4 files changed, 54 insertions(+), 42 deletions(-) diff --git a/drivers/net/mdio/fwnode_mdio.c b/drivers/net/mdio/fwnode_mdio.c index 9b41d4697..ba7091518 100644 --- a/drivers/net/mdio/fwnode_mdio.c +++ b/drivers/net/mdio/fwnode_mdio.c @@ -92,11 +92,6 @@ int fwnode_mdiobus_phy_device_register(struct mii_bus *mdio, if (fwnode_property_read_bool(child, "broken-turn-around")) mdio->phy_ignore_ta_mask |= 1 << addr; - fwnode_property_read_u32(child, "reset-assert-us", - &phy->mdio.reset_assert_delay); - fwnode_property_read_u32(child, "reset-deassert-us", - &phy->mdio.reset_deassert_delay); - /* Associate the fwnode with the device structure so it * can be looked up later */ diff --git a/drivers/net/phy/mdio_bus.c b/drivers/net/phy/mdio_bus.c index cad6ed3aa..cc3f9cfb1 100644 --- a/drivers/net/phy/mdio_bus.c +++ b/drivers/net/phy/mdio_bus.c @@ -33,33 +33,6 @@ #define CREATE_TRACE_POINTS #include -static int mdiobus_register_gpiod(struct mdio_device *mdiodev) -{ - /* Deassert the optional reset signal */ - mdiodev->reset_gpio = gpiod_get_optional(&mdiodev->dev, - "reset", GPIOD_OUT_LOW); - if (IS_ERR(mdiodev->reset_gpio)) - return PTR_ERR(mdiodev->reset_gpio); - - if (mdiodev->reset_gpio) - gpiod_set_consumer_name(mdiodev->reset_gpio, "PHY reset"); - - return 0; -} - -static int mdiobus_register_reset(struct mdio_device *mdiodev) -{ - struct reset_control *reset; - - reset = reset_control_get_optional_exclusive(&mdiodev->dev, "phy"); - if (IS_ERR(reset)) - return PTR_ERR(reset); - - mdiodev->reset_ctrl = reset; - - return 0; -} - int mdiobus_register_device(struct mdio_device *mdiodev) { int err; @@ -68,16 +41,9 @@ int mdiobus_register_device(struct mdio_device *mdiodev) return -EBUSY; if (mdiodev->flags & MDIO_DEVICE_FLAG_PHY) { - err = mdiobus_register_gpiod(mdiodev); + err = mdio_device_register_reset(mdiodev); if (err) return err; - - err = mdiobus_register_reset(mdiodev); - if (err) - return err; - - /* Assert the reset signal */ - mdio_device_reset(mdiodev, 1); } mdiodev->bus->mdio_map[mdiodev->addr] = mdiodev; @@ -91,8 +57,7 @@ int mdiobus_unregister_device(struct mdio_device *mdiodev) if (mdiodev->bus->mdio_map[mdiodev->addr] != mdiodev) return -EINVAL; - gpiod_put(mdiodev->reset_gpio); - reset_control_put(mdiodev->reset_ctrl); + mdio_device_unregister_reset(mdiodev); mdiodev->bus->mdio_map[mdiodev->addr] = NULL; diff --git a/drivers/net/phy/mdio_device.c b/drivers/net/phy/mdio_device.c index f64176e0e..eb8237095 100644 --- a/drivers/net/phy/mdio_device.c +++ b/drivers/net/phy/mdio_device.c @@ -74,6 +74,56 @@ struct mdio_device *mdio_device_create(struct mii_bus *bus, int addr) } EXPORT_SYMBOL(mdio_device_create); +/** + * mdio_device_register_reset - Read and initialize the reset properties of + * an mdio device + * @mdiodev: mdio_device structure + */ +int mdio_device_register_reset(struct mdio_device *mdiodev) +{ + struct reset_control *reset; + + /* Read optional firmware properties */ + fwnode_property_read_u32(dev_fwnode(&mdiodev->dev), "reset-assert-us", + &mdiodev->reset_assert_delay); + fwnode_property_read_u32(dev_fwnode(&mdiodev->dev), "reset-deassert-us", + &mdiodev->reset_deassert_delay); + + /* reset-gpio, bring up deasserted */ + mdiodev->reset_gpio = gpiod_get_optional(&mdiodev->dev, "reset", + GPIOD_OUT_LOW); + + if (IS_ERR(mdiodev->reset_gpio)) + return PTR_ERR(mdiodev->reset_gpio); + + if (mdiodev->reset_gpio) + gpiod_set_consumer_name(mdiodev->reset_gpio, "PHY reset"); + + reset = reset_control_get_optional_exclusive(&mdiodev->dev, "phy"); + if (IS_ERR(reset)) + return PTR_ERR(reset); + + mdiodev->reset_ctrl = reset; + + /* Assert the reset signal */ + mdio_device_reset(mdiodev, 1); + + return 0; +} +EXPORT_SYMBOL(mdio_device_register_reset); + +/** + * mdio_device_unregister_reset - uninitialize the reset properties of + * an mdio device + * @mdiodev: mdio_device structure + */ +void mdio_device_unregister_reset(struct mdio_device *mdiodev) +{ + gpiod_put(mdiodev->reset_gpio); + reset_control_put(mdiodev->reset_ctrl); +} +EXPORT_SYMBOL(mdio_device_unregister_reset); + /** * mdio_device_register - Register the mdio device on the MDIO bus * @mdiodev: mdio_device structure to be added to the MDIO bus diff --git a/include/linux/mdio.h b/include/linux/mdio.h index c640ba44d..4cedcae08 100644 --- a/include/linux/mdio.h +++ b/include/linux/mdio.h @@ -90,6 +90,8 @@ static inline void *mdiodev_get_drvdata(struct mdio_device *mdio) void mdio_device_free(struct mdio_device *mdiodev); struct mdio_device *mdio_device_create(struct mii_bus *bus, int addr); +int mdio_device_register_reset(struct mdio_device *mdiodev); +void mdio_device_unregister_reset(struct mdio_device *mdiodev); int mdio_device_register(struct mdio_device *mdiodev); void mdio_device_remove(struct mdio_device *mdiodev); void mdio_device_reset(struct mdio_device *mdiodev, int value); -- 2.39.5 Changed fwnode_property_read_u32() in mdio_device_register_reset() to device_property_read_u32(), which is more appropriate here. Signed-off-by: Buday Csaba --- drivers/net/phy/mdio_device.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/drivers/net/phy/mdio_device.c b/drivers/net/phy/mdio_device.c index eb8237095..d812ae2a0 100644 --- a/drivers/net/phy/mdio_device.c +++ b/drivers/net/phy/mdio_device.c @@ -84,9 +84,9 @@ int mdio_device_register_reset(struct mdio_device *mdiodev) struct reset_control *reset; /* Read optional firmware properties */ - fwnode_property_read_u32(dev_fwnode(&mdiodev->dev), "reset-assert-us", + device_property_read_u32(&mdiodev->dev, "reset-assert-us", &mdiodev->reset_assert_delay); - fwnode_property_read_u32(dev_fwnode(&mdiodev->dev), "reset-deassert-us", + device_property_read_u32(&mdiodev->dev, "reset-deassert-us", &mdiodev->reset_deassert_delay); /* reset-gpio, bring up deasserted */ -- 2.39.5 Some Ethernet PHYs require a hard reset before accessing their MDIO registers. When the ID is not provided by a compatible string, reading the PHY ID may fail on such devices. This patch introduces a new device tree property called `phy-id-read-needs-reset`, which can be used to hard reset the PHY before attempting to read its ID via MDIO. Signed-off-by: Buday Csaba --- Documentation/devicetree/bindings/net/ethernet-phy.yaml | 8 ++++++++ 1 file changed, 8 insertions(+) diff --git a/Documentation/devicetree/bindings/net/ethernet-phy.yaml b/Documentation/devicetree/bindings/net/ethernet-phy.yaml index 2ec2d9fda..b570f8038 100644 --- a/Documentation/devicetree/bindings/net/ethernet-phy.yaml +++ b/Documentation/devicetree/bindings/net/ethernet-phy.yaml @@ -215,6 +215,14 @@ properties: Delay after the reset was deasserted in microseconds. If this property is missing the delay will be skipped. + phy-id-read-needs-reset: + $ref: /schemas/types.yaml#/definitions/flag + description: + Some PHYs require a hard reset before accessing MDIO registers. + This workaround allows auto-detection of the PHY ID in such cases. + When the PHY ID is provided with the 'compatible' string, setting + this property has no effect. + sfp: $ref: /schemas/types.yaml#/definitions/phandle description: -- 2.39.5 Implement support for the `phy-id-read-needs-reset` device tree property. When the ID of an ethernet PHY is not provided by the 'compatible' string in the device tree, its actual ID is read via the MDIO bus. For some PHYs this could be unsafe, since a hard reset may be necessary to safely access the MDIO registers. This patch performs the hard-reset before attempting to read the ID, when the mentioned device tree property is present. There were previous attempts to implement such functionality, I tried to collect a few of these (see links). Link: https://lore.kernel.org/lkml/1499346330-12166-2-git-send-email-richard.leitner@skidata.com/ Link: https://lore.kernel.org/all/20230405-net-next-topic-net-phy-reset-v1-0-7e5329f08002@pengutronix.de/ Link: https://lore.kernel.org/netdev/20250709133222.48802-4-buday.csaba@prolan.hu/ Signed-off-by: Buday Csaba --- V1 -> V2: - renamed DT property `reset-phy-before-probe` to `phy-id-read-needs-reset` - renamed fwnode_reset_phy_before_probe() to fwnode_reset_phy() - added kernel-doc for fwnode_reset_phy() - improved error handling in fwnode_reset_phy() --- drivers/net/mdio/fwnode_mdio.c | 37 +++++++++++++++++++++++++++++++++- 1 file changed, 36 insertions(+), 1 deletion(-) diff --git a/drivers/net/mdio/fwnode_mdio.c b/drivers/net/mdio/fwnode_mdio.c index ba7091518..6987b1a51 100644 --- a/drivers/net/mdio/fwnode_mdio.c +++ b/drivers/net/mdio/fwnode_mdio.c @@ -114,6 +114,38 @@ int fwnode_mdiobus_phy_device_register(struct mii_bus *mdio, } EXPORT_SYMBOL(fwnode_mdiobus_phy_device_register); +/** + * fwnode_reset_phy() - Hard-reset a PHY before registration + */ +static int fwnode_reset_phy(struct mii_bus *bus, u32 addr, + struct fwnode_handle *phy_node) +{ + struct mdio_device *tmpdev; + int err; + + tmpdev = mdio_device_create(bus, addr); + if (IS_ERR(tmpdev)) + return PTR_ERR(tmpdev); + + fwnode_handle_get(phy_node); + device_set_node(&tmpdev->dev, phy_node); + err = mdio_device_register_reset(tmpdev); + if (err) { + mdio_device_free(tmpdev); + return err; + } + + mdio_device_reset(tmpdev, 1); + mdio_device_reset(tmpdev, 0); + + mdio_device_unregister_reset(tmpdev); + + mdio_device_free(tmpdev); + fwnode_handle_put(phy_node); + + return 0; +} + int fwnode_mdiobus_register_phy(struct mii_bus *bus, struct fwnode_handle *child, u32 addr) { @@ -129,8 +161,11 @@ int fwnode_mdiobus_register_phy(struct mii_bus *bus, return PTR_ERR(mii_ts); is_c45 = fwnode_device_is_compatible(child, "ethernet-phy-ieee802.3-c45"); - if (is_c45 || fwnode_get_phy_id(child, &phy_id)) + if (is_c45 || fwnode_get_phy_id(child, &phy_id)) { + if (fwnode_property_present(child, "reset-phy-before-probe")) + fwnode_reset_phy(bus, addr, child); phy = get_phy_device(bus, addr, is_c45); + } else phy = phy_device_create(bus, addr, phy_id, 0, NULL); if (IS_ERR(phy)) { -- 2.39.5