[PATCH 5.3 005/344] net/phy: fix DP83865 10 Mbps HDX loopback disable function

From: Greg Kroah-Hartman
Date: Thu Oct 03 2019 - 12:39:25 EST


From: Peter Mamonov <pmamonov@xxxxxxxxx>

[ Upstream commit e47488b2df7f9cb405789c7f5d4c27909fc597ae ]

According to the DP83865 datasheet "the 10 Mbps HDX loopback can be
disabled in the expanded memory register 0x1C0.1". The driver erroneously
used bit 0 instead of bit 1.

Fixes: 4621bf129856 ("phy: Add file missed in previous commit.")
Signed-off-by: Peter Mamonov <pmamonov@xxxxxxxxx>
Reviewed-by: Andrew Lunn <andrew@xxxxxxx>
Signed-off-by: Jakub Kicinski <jakub.kicinski@xxxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
drivers/net/phy/national.c | 9 ++++++---
1 file changed, 6 insertions(+), 3 deletions(-)

--- a/drivers/net/phy/national.c
+++ b/drivers/net/phy/national.c
@@ -105,14 +105,17 @@ static void ns_giga_speed_fallback(struc

static void ns_10_base_t_hdx_loopack(struct phy_device *phydev, int disable)
{
+ u16 lb_dis = BIT(1);
+
if (disable)
- ns_exp_write(phydev, 0x1c0, ns_exp_read(phydev, 0x1c0) | 1);
+ ns_exp_write(phydev, 0x1c0,
+ ns_exp_read(phydev, 0x1c0) | lb_dis);
else
ns_exp_write(phydev, 0x1c0,
- ns_exp_read(phydev, 0x1c0) & 0xfffe);
+ ns_exp_read(phydev, 0x1c0) & ~lb_dis);

pr_debug("10BASE-T HDX loopback %s\n",
- (ns_exp_read(phydev, 0x1c0) & 0x0001) ? "off" : "on");
+ (ns_exp_read(phydev, 0x1c0) & lb_dis) ? "off" : "on");
}

static int ns_config_init(struct phy_device *phydev)