From 2f878491b3674b7c61d9b214aec35c66e5946da9 Mon Sep 17 00:00:00 2001 From: Icenowy Zheng Date: Mon, 5 Jun 2017 01:53:23 +0800 Subject: [PATCH] net-next: stmmac: dwmac-sun8i: ensure the EPHY is properly reseted The EPHY may be already enabled by bootloaders which have Ethernet capability (e.g. current U-Boot). Thus it should be reseted properly before doing the enabling sequence in the dwmac-sun8i driver, otherwise the EMAC reset process may fail if no cable is plugged, and then fail the dwmac-sun8i probing. Tested on Orange Pi PC, One and Zero. All the boards fail to have dwmac-sun8i probed with "EMAC reset timeout" without cable plugged before, and with this fix they're now all able to successfully probe the EMAC without cable plugged and then use the connection after a cable is hot-plugged in. Fixes: 9f93ac8d408 ("net-next: stmmac: Add dwmac-sun8i") Signed-off-by: Icenowy Zheng Tested-by: Corentin Labbe Acked-by: Corentin Labbe Reviewed-by: Corentin Labbe Acked-by: is not as formal as Signed-off-by:. It is a record that the acker Reviewed-by: is similar. Signed-off-by: David S. Miller --- drivers/net/ethernet/stmicro/stmmac/dwmac-sun8i.c | 5 +++++ 1 file changed, 5 insertions(+) diff --git a/drivers/net/ethernet/stmicro/stmmac/dwmac-sun8i.c b/drivers/net/ethernet/stmicro/stmmac/dwmac-sun8i.c index 1a6bfe6..54f93ee 100644 --- a/drivers/net/ethernet/stmicro/stmmac/dwmac-sun8i.c +++ b/drivers/net/ethernet/stmicro/stmmac/dwmac-sun8i.c @@ -750,6 +750,11 @@ static int sun8i_dwmac_power_internal_phy(struct stmmac_priv *priv) return ret; } + /* Make sure the EPHY is properly reseted, as U-Boot may leave + * it at deasserted state, and thus it may fail to reset EMAC. + */ + reset_control_assert(gmac->rst_ephy); + ret = reset_control_deassert(gmac->rst_ephy); if (ret) { dev_err(priv->device, "Cannot deassert ephy\n"); -- 2.7.4