| From 598d6389f41c1e01b70df7d8b1056c3839e0c1c2 Mon Sep 17 00:00:00 2001 |
| From: Phil Elwell <phil@raspberrypi.com> |
| Date: Tue, 15 Dec 2020 16:38:37 +0000 |
| Subject: [PATCH] net: lan78xx: Ack pending PHY ints when resetting |
| |
| lan78xx_link_reset explicitly clears the MAC's view of the PHY's IRQ |
| status. In doing so it potentially leaves the PHY with a pending |
| interrupt that will never be acknowledged, at which point no further |
| interrupts will be generated. |
| |
| Avoid the problem by acknowledging any pending PHY interrupt after |
| clearing the MAC's status bit. |
| |
| See: https://github.com/raspberrypi/linux/issues/2937 |
| |
| Signed-off-by: Phil Elwell <phil@raspberrypi.com> |
| --- |
| drivers/net/usb/lan78xx.c | 3 +++ |
| 1 file changed, 3 insertions(+) |
| |
| --- a/drivers/net/usb/lan78xx.c |
| +++ b/drivers/net/usb/lan78xx.c |
| @@ -1179,6 +1179,9 @@ static int lan78xx_link_reset(struct lan |
| if (unlikely(ret < 0)) |
| return -EIO; |
| |
| + /* Acknowledge any pending PHY interrupt, lest it be the last */ |
| + phy_read(phydev, LAN88XX_INT_STS); |
| + |
| mutex_lock(&phydev->lock); |
| phy_read_status(phydev); |
| link = phydev->link; |