[PATCH net-next] net: phy: perform a PHY reset on resume

From: Francesco Dolcini
Date: Sat Dec 11 2021 - 08:02:26 EST


Perform a PHY reset in phy_init_hw() to ensure that the PHY is working
after resume. This is required if the PHY was powered down in suspend
like it is done by the freescale FEC driver in fec_suspend().

Link: https://lore.kernel.org/netdev/20211206101326.1022527-1-philippe.schenker@xxxxxxxxxxx/
Signed-off-by: Francesco Dolcini <francesco.dolcini@xxxxxxxxxxx>

---

Philippe: what about something like that? Only compile tested, but I see no reason for this not solving the issue.

Any delay required on the reset can be specified using reset-assert-us/reset-deassert-us.

---
drivers/net/phy/phy_device.c | 3 ++-
1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/drivers/net/phy/phy_device.c b/drivers/net/phy/phy_device.c
index 74d8e1dc125f..7eab0c054adf 100644
--- a/drivers/net/phy/phy_device.c
+++ b/drivers/net/phy/phy_device.c
@@ -1158,7 +1158,8 @@ int phy_init_hw(struct phy_device *phydev)
{
int ret = 0;

- /* Deassert the reset signal */
+ /* phy reset required if the phy was powered down during suspend */
+ phy_device_reset(phydev, 1);
phy_device_reset(phydev, 0);

if (!phydev->drv)
--
2.25.1