[PATCH net-next 5/5] net: phy: adin1100: Skip the soft reset on ADIN1110/ADIN2111

[Iustin Stolniceanu]

The ADIN1110 and ADIN2111 MAC-PHYs integrate the ADIN1100 PHY and use
this driver. On these devices, CRSM_SFT_RST resets the whole chip, not
only the PHY, undoing the configuration done by the MAC driver before
the PHY is attached. MDIO reads also return stale data until the reset
completes.

The MAC driver already resets the chip before attaching the PHY, so
skip the soft reset on these devices.

Signed-off-by: Iustin Stolniceanu <iustin.stolniceanu@xxxxxxxxxx>
---
 drivers/net/phy/adin1100.c | 9 +++++++++
 1 file changed, 9 insertions(+)

diff --git a/drivers/net/phy/adin1100.c b/drivers/net/phy/adin1100.c
index 8f9753d4318c..7b4e68285a9d 100644
--- a/drivers/net/phy/adin1100.c
+++ b/drivers/net/phy/adin1100.c
@@ -232,6 +232,15 @@ static int adin_soft_reset(struct phy_device *phydev)
 {
 	int ret;
 
+	/* On the ADIN1110/ADIN2111 MAC-PHYs, CRSM_SFT_RST resets the whole
+	 * chip, undoing the MAC driver's setup, and MDIO reads return stale
+	 * data until it completes. The MAC driver has already reset the
+	 * chip, so skip it here.
+	 */
+	if (phy_id_compare_model(phydev->phy_id, PHY_ID_ADIN1110) ||
+	    phy_id_compare_model(phydev->phy_id, PHY_ID_ADIN2111))
+		return 0;
+
 	ret = phy_set_bits_mmd(phydev, MDIO_MMD_VEND1, ADIN_CRSM_SFT_RST, ADIN_CRSM_SFT_RST_EN);
 	if (ret < 0)
 		return ret;
-- 
2.43.0