From 0ba13995be9b416ea1d3daaf3ba871a67f45899b Mon Sep 17 00:00:00 2001 From: Xu Liang Date: Wed, 15 Mar 2023 00:30:23 +0800 Subject: [PATCH] net: phy: mxl-gpy: enhance delay time required by loopback disable function GPY2xx devices need 3 seconds to fully switch out of loopback mode before it can safely re-enter loopback mode. Implement timeout mechanism to guarantee 3 seconds waited before re-enter loopback mode. Signed-off-by: Xu Liang Signed-off-by: David S. Miller --- drivers/net/phy/mxl-gpy.c | 35 +++++++++++++++++++++++++++++------ 1 file changed, 29 insertions(+), 6 deletions(-) diff --git a/drivers/net/phy/mxl-gpy.c b/drivers/net/phy/mxl-gpy.c index e5972b4..8e6bb97 100644 --- a/drivers/net/phy/mxl-gpy.c +++ b/drivers/net/phy/mxl-gpy.c @@ -107,6 +107,13 @@ struct gpy_priv { u8 fw_major; u8 fw_minor; + + /* It takes 3 seconds to fully switch out of loopback mode before + * it can safely re-enter loopback mode. Record the time when + * loopback is disabled. Check and wait if necessary before loopback + * is enabled. + */ + u64 lb_dis_to; }; static const struct { @@ -769,18 +776,34 @@ static void gpy_get_wol(struct phy_device *phydev, static int gpy_loopback(struct phy_device *phydev, bool enable) { + struct gpy_priv *priv = phydev->priv; + u16 set = 0; int ret; - ret = phy_modify(phydev, MII_BMCR, BMCR_LOOPBACK, - enable ? BMCR_LOOPBACK : 0); - if (!ret) { - /* It takes some time for PHY device to switch - * into/out-of loopback mode. + if (enable) { + u64 now = get_jiffies_64(); + + /* wait until 3 seconds from last disable */ + if (time_before64(now, priv->lb_dis_to)) + msleep(jiffies64_to_msecs(priv->lb_dis_to - now)); + + set = BMCR_LOOPBACK; + } + + ret = phy_modify(phydev, MII_BMCR, BMCR_LOOPBACK, set); + if (ret <= 0) + return ret; + + if (enable) { + /* It takes some time for PHY device to switch into + * loopback mode. */ msleep(100); + } else { + priv->lb_dis_to = get_jiffies_64() + HZ * 3; } - return ret; + return 0; } static int gpy115_loopback(struct phy_device *phydev, bool enable) -- 2.7.4