From bc66fa87d4fda9053a8145e5718fc278c2b88253 Mon Sep 17 00:00:00 2001 From: Xiaolei Wang Date: Wed, 30 Nov 2022 10:12:16 +0800 Subject: [PATCH] net: phy: Add link between phy dev and mac dev If the external phy used by current mac interface is managed by another mac interface, it means that this network port cannot work independently, especially when the system suspends and resumes, the following trace may appear, so we should create a device link between phy dev and mac dev. WARNING: CPU: 0 PID: 24 at drivers/net/phy/phy.c:983 phy_error+0x20/0x68 Modules linked in: CPU: 0 PID: 24 Comm: kworker/0:2 Not tainted 6.1.0-rc3-00011-g5aaef24b5c6d-dirty #34 Hardware name: Freescale i.MX6 SoloX (Device Tree) Workqueue: events_power_efficient phy_state_machine unwind_backtrace from show_stack+0x10/0x14 show_stack from dump_stack_lvl+0x68/0x90 dump_stack_lvl from __warn+0xb4/0x24c __warn from warn_slowpath_fmt+0x5c/0xd8 warn_slowpath_fmt from phy_error+0x20/0x68 phy_error from phy_state_machine+0x22c/0x23c phy_state_machine from process_one_work+0x288/0x744 process_one_work from worker_thread+0x3c/0x500 worker_thread from kthread+0xf0/0x114 kthread from ret_from_fork+0x14/0x28 Exception stack(0xf0951fb0 to 0xf0951ff8) Signed-off-by: Xiaolei Wang Tested-by: Florian Fainelli Reviewed-by: Florian Fainelli Link: https://lore.kernel.org/r/20221130021216.1052230-1-xiaolei.wang@windriver.com Signed-off-by: Jakub Kicinski --- drivers/net/phy/phy_device.c | 12 ++++++++++++ include/linux/phy.h | 4 ++++ 2 files changed, 16 insertions(+) diff --git a/drivers/net/phy/phy_device.c b/drivers/net/phy/phy_device.c index 8cff61dbc4b5..716870a4499c 100644 --- a/drivers/net/phy/phy_device.c +++ b/drivers/net/phy/phy_device.c @@ -1512,6 +1512,15 @@ int phy_attach_direct(struct net_device *dev, struct phy_device *phydev, phy_resume(phydev); phy_led_triggers_register(phydev); + /** + * If the external phy used by current mac interface is managed by + * another mac interface, so we should create a device link between + * phy dev and mac dev. + */ + if (phydev->mdio.bus->parent && dev->dev.parent != phydev->mdio.bus->parent) + phydev->devlink = device_link_add(dev->dev.parent, &phydev->mdio.dev, + DL_FLAG_PM_RUNTIME | DL_FLAG_STATELESS); + return err; error: @@ -1750,6 +1759,9 @@ void phy_detach(struct phy_device *phydev) struct module *ndev_owner = NULL; struct mii_bus *bus; + if (phydev->devlink) + device_link_del(phydev->devlink); + if (phydev->sysfs_links) { if (dev) sysfs_remove_link(&dev->dev.kobj, "phydev"); diff --git a/include/linux/phy.h b/include/linux/phy.h index 9a3752c0c444..71eeb4e3b1fd 100644 --- a/include/linux/phy.h +++ b/include/linux/phy.h @@ -529,6 +529,8 @@ struct macsec_ops; * * @mdio: MDIO bus this PHY is on * @drv: Pointer to the driver for this PHY instance + * @devlink: Create a link between phy dev and mac dev, if the external phy + * used by current mac interface is managed by another mac interface. * @phy_id: UID for this device found during discovery * @c45_ids: 802.3-c45 Device Identifiers if is_c45. * @is_c45: Set to true if this PHY uses clause 45 addressing. @@ -618,6 +620,8 @@ struct phy_device { /* And management functions */ struct phy_driver *drv; + struct device_link *devlink; + u32 phy_id; struct phy_c45_device_ids c45_ids;