net: phy: micrel: always set shared->phydev for LAN8814

[ Upstream commit 399d109 ]

Currently, during the LAN8814 PTP probe shared->phydev is only set if PTP
clock gets actually set, otherwise the function will return before setting
it.

This is an issue as shared->phydev is unconditionally being used when IRQ
is being handled, especially in lan8814_gpio_process_cap and since it was
not set it will cause a NULL pointer exception and crash the kernel.

So, simply always set shared->phydev to avoid the NULL pointer exception.

Fixes: b3f1a08 ("net: phy: micrel: Add support for PTP_PF_EXTTS for lan8814")
Signed-off-by: Robert Marko <robert.marko@sartura.hr>
Tested-by: Horatiu Vultur <horatiu.vultur@microchip.com>
Link: https://patch.msgid.link/20251021132034.983936-1-robert.marko@sartura.hr
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
(cherry picked from commit da1ef8e9eb5d4a12bec32d11636e521e7d529b9e)

Author: robimarko

drivers/net/phy/micrel.c

@@ -3870,6 +3870,8 @@ static int lan8814_ptp_probe_once(struct phy_device *phydev)
 {
 	struct lan8814_shared_priv *shared = phydev->shared->priv;
 
+	shared->phydev = phydev;
+
 	/* Initialise shared lock for clock*/
 	mutex_init(&shared->shared_lock);
 
@@ -3921,8 +3923,6 @@ static int lan8814_ptp_probe_once(struct phy_device *phydev)
 
 	phydev_dbg(phydev, "successfully registered ptp clock\n");
 
-	shared->phydev = phydev;
-
 	/* The EP.4 is shared between all the PHYs in the package and also it
 	 * can be accessed by any of the PHYs
 	 */