From 906e8d9792b1c4a8b58c1383f4c00fc4c9936fc3 Mon Sep 17 00:00:00 2001 From: Bruce Allan <bruce.w.allan@intel.com> Date: Wed, 1 Jul 2009 13:28:50 +0000 Subject: [PATCH] e1000e: delay second read of PHY_STATUS register on failure of first read Some PHYs may require two reads of the PHY_STATUS register to determine the link status. If the PHY is being accessed by another thread it is possible the first read could timeout and fail. In this case, put a delay in so the second read will pick up the correct link status. Signed-off-by: Bruce Allan <bruce.w.allan@intel.com> Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com> Signed-off-by: David S. Miller <davem@davemloft.net> --- drivers/net/e1000e/phy.c | 7 ++++++- 1 file changed, 6 insertions(+), 1 deletion(-) diff --git a/drivers/net/e1000e/phy.c b/drivers/net/e1000e/phy.c index d8453946bff8..994401fd0664 100644 --- a/drivers/net/e1000e/phy.c +++ b/drivers/net/e1000e/phy.c @@ -1531,7 +1531,12 @@ s32 e1000e_phy_has_link_generic(struct e1000_hw *hw, u32 iterations, */ ret_val = e1e_rphy(hw, PHY_STATUS, &phy_status); if (ret_val) - break; + /* + * If the first read fails, another entity may have + * ownership of the resources, wait and try again to + * see if they have relinquished the resources yet. + */ + udelay(usec_interval); ret_val = e1e_rphy(hw, PHY_STATUS, &phy_status); if (ret_val) break; -- 2.20.1