From 9e70485b40c8306298adea8bdc867ca27f88955a Mon Sep 17 00:00:00 2001 From: Marek Vasut Date: Sat, 10 Oct 2020 11:10:00 +0200 Subject: [PATCH] net: fec: Fix phy_device lookup for phy_reset_after_clk_enable() [ Upstream commit 64a632da538a6827fad0ea461925cedb9899ebe2 ] The phy_reset_after_clk_enable() is always called with ndev->phydev, however that pointer may be NULL even though the PHY device instance already exists and is sufficient to perform the PHY reset. This condition happens in fec_open(), where the clock must be enabled first, then the PHY must be reset, and then the PHY IDs can be read out of the PHY. If the PHY still is not bound to the MAC, but there is OF PHY node and a matching PHY device instance already, use the OF PHY node to obtain the PHY device instance, and then use that PHY device instance when triggering the PHY reset. Fixes: 1b0a83ac04e3 ("net: fec: add phy_reset_after_clk_enable() support") Signed-off-by: Marek Vasut Cc: Christoph Niedermaier Cc: David S. Miller Cc: NXP Linux Team Cc: Richard Leitner Cc: Shawn Guo Signed-off-by: Jakub Kicinski Signed-off-by: Greg Kroah-Hartman --- drivers/net/ethernet/freescale/fec_main.c | 25 +++++++++++++++++++++-- 1 file changed, 23 insertions(+), 2 deletions(-) diff --git a/drivers/net/ethernet/freescale/fec_main.c b/drivers/net/ethernet/freescale/fec_main.c index a0e4b12ac4ea..c04261806d0e 100644 --- a/drivers/net/ethernet/freescale/fec_main.c +++ b/drivers/net/ethernet/freescale/fec_main.c @@ -1945,6 +1945,27 @@ out: return ret; } +static void fec_enet_phy_reset_after_clk_enable(struct net_device *ndev) +{ + struct fec_enet_private *fep = netdev_priv(ndev); + struct phy_device *phy_dev = ndev->phydev; + + if (phy_dev) { + phy_reset_after_clk_enable(phy_dev); + } else if (fep->phy_node) { + /* + * If the PHY still is not bound to the MAC, but there is + * OF PHY node and a matching PHY device instance already, + * use the OF PHY node to obtain the PHY device instance, + * and then use that PHY device instance when triggering + * the PHY reset. + */ + phy_dev = of_phy_find_device(fep->phy_node); + phy_reset_after_clk_enable(phy_dev); + put_device(&phy_dev->mdio.dev); + } +} + static int fec_enet_clk_enable(struct net_device *ndev, bool enable) { struct fec_enet_private *fep = netdev_priv(ndev); @@ -1971,7 +1992,7 @@ static int fec_enet_clk_enable(struct net_device *ndev, bool enable) if (ret) goto failed_clk_ref; - phy_reset_after_clk_enable(ndev->phydev); + fec_enet_phy_reset_after_clk_enable(ndev); } else { clk_disable_unprepare(fep->clk_enet_out); if (fep->clk_ptp) { @@ -2991,7 +3012,7 @@ fec_enet_open(struct net_device *ndev) * phy_reset_after_clk_enable() before because the PHY wasn't probed. */ if (reset_again) - phy_reset_after_clk_enable(ndev->phydev); + fec_enet_phy_reset_after_clk_enable(ndev); if (fep->quirks & FEC_QUIRK_ERR006687) imx6q_cpuidle_fec_irqs_used();