Commit 5537a467 authored Sep 08, 2025 by Oleksij Rempel Committed by Jakub Kicinski Sep 10, 2025

net: usb: asix: ax88772: drop phylink use in PM to avoid MDIO runtime PM wakeups



Drop phylink_{suspend,resume}() from ax88772 PM callbacks.

MDIO bus accesses have their own runtime-PM handling and will try to
wake the device if it is suspended. Such wake attempts must not happen
from PM callbacks while the device PM lock is held. Since phylink
{sus|re}sume may trigger MDIO, it must not be called in PM context.

No extra phylink PM handling is required for this driver:
- .ndo_open/.ndo_stop control the phylink start/stop lifecycle.
- ethtool/phylib entry points run in process context, not PM.
- phylink MAC ops program the MAC on link changes after resume.

Fixes: e0bffe3e ("net: asix: ax88772: migrate to phylink")
Reported-by: Hubert Wiśniewski <hubert.wisniewski.25632@gmail.com>
Cc: stable@vger.kernel.org
Signed-off-by: Oleksij Rempel <o.rempel@pengutronix.de>
Tested-by: Hubert Wiśniewski <hubert.wisniewski.25632@gmail.com>
Tested-by: Xu Yang <xu.yang_2@nxp.com>
Link: https://patch.msgid.link/20250908112619.2900723-1-o.rempel@pengutronix.de


Signed-off-by: Jakub Kicinski <kuba@kernel.org>

parent 6fef6ae7

drivers/net/usb/asix_devices.c

+0 −13

Original line number	Diff line number	Diff line
		@@ -607,15 +607,8 @@ static const struct net_device_ops ax88772_netdev_ops = {

		static void ax88772_suspend(struct usbnet *dev)
		{
		struct asix_common_private *priv = dev->driver_priv;
		u16 medium;

		if (netif_running(dev->net)) {
		rtnl_lock();
		phylink_suspend(priv->phylink, false);
		rtnl_unlock();
		}

		/* Stop MAC operation */
		medium = asix_read_medium_status(dev, 1);
		medium &= ~AX_MEDIUM_RE;
		@@ -644,12 +637,6 @@ static void ax88772_resume(struct usbnet *dev)
		for (i = 0; i < 3; i++)
		if (!priv->reset(dev, 1))
		break;

		if (netif_running(dev->net)) {
		rtnl_lock();
		phylink_resume(priv->phylink);
		rtnl_unlock();
		}
		}

		static int asix_resume(struct usb_interface *intf)