[PATCH RESEND net-next v6 6/7] net: phy: qcom: at803x: Avoid hibernating if MAC requires RX clock

Romain Gantois romain.gantois at bootlin.com
Tue Mar 26 06:32:12 PDT 2024


From: "Russell King (Oracle)" <rmk+kernel at armlinux.org.uk>

Stmmac controllers connected to an at803x PHY cannot resume properly after
suspend when WoL is enabled. This happens because the MAC requires an RX
clock generated by the PHY to initialize its hardware properly. But the RX
clock is cut when the PHY suspends and isn't brought up until the MAC
driver resumes the phylink.

Prevent the at803x PHY driver from going into suspend if the attached MAC
driver always requires an RX clock signal.

Reported-by: Clark Wang <xiaoning.wang at nxp.com>
Link: https://lore.kernel.org/all/20230202081559.3553637-1-xiaoning.wang@nxp.com/
Signed-off-by: Russell King (Oracle) <rmk+kernel at armlinux.org.uk>
[rgantois: commit log]
Signed-off-by: Romain Gantois <romain.gantois at bootlin.com>
Reviewed-by: Andrew Lunn <andrew at lunn.ch>
---
 drivers/net/phy/qcom/at803x.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/drivers/net/phy/qcom/at803x.c b/drivers/net/phy/qcom/at803x.c
index 4717c59d51d0..2a221b81cf37 100644
--- a/drivers/net/phy/qcom/at803x.c
+++ b/drivers/net/phy/qcom/at803x.c
@@ -426,7 +426,8 @@ static int at803x_hibernation_mode_config(struct phy_device *phydev)
 	/* The default after hardware reset is hibernation mode enabled. After
 	 * software reset, the value is retained.
 	 */
-	if (!(priv->flags & AT803X_DISABLE_HIBERNATION_MODE))
+	if (!(priv->flags & AT803X_DISABLE_HIBERNATION_MODE) &&
+	    !(phydev->dev_flags & PHY_F_RXC_ALWAYS_ON))
 		return 0;
 
 	return at803x_debug_reg_mask(phydev, AT803X_DEBUG_REG_HIB_CTRL,

-- 
2.44.0




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