[PATCH net] r8169: fix page read in r8168g_mdio_read

[PATCH net] r8169: fix page read in r8168g_mdio_read

[Heiner Kallweit]

Functions like phy_modify_paged() read the current page, on Realtek
PHY's this means reading the value of register 0x1f. Add special
handling for reading this register, similar to what we do already
in r8168g_mdio_write(). Currently we read a random value that by
chance seems to be 0 always.

Fixes: a2928d28643e ("r8169: use paged versions of phylib MDIO access functions")
Signed-off-by: Heiner Kallweit <hkallweit1@gmail.com>
---
 drivers/net/ethernet/realtek/r8169_main.c | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/drivers/net/ethernet/realtek/r8169_main.c b/drivers/net/ethernet/realtek/r8169_main.c
index 0704f8bd1..8a7b22301 100644
--- a/drivers/net/ethernet/realtek/r8169_main.c
+++ b/drivers/net/ethernet/realtek/r8169_main.c
@@ -910,6 +910,9 @@ static void r8168g_mdio_write(struct rtl8169_private *tp, int reg, int value)
 
 static int r8168g_mdio_read(struct rtl8169_private *tp, int reg)
 {
+	if (reg == 0x1f)
+		return tp->ocp_base == OCP_STD_PHY_BASE ? 0 : tp->ocp_base >> 4;
+
 	if (tp->ocp_base != OCP_STD_PHY_BASE)
 		reg -= 0x10;
 
-- 
2.24.0

Re: [PATCH net] r8169: fix page read in r8168g_mdio_read

[David Miller]

From: Heiner Kallweit <hkallweit1@gmail.com>
Date: Wed, 6 Nov 2019 21:51:31 +0100

> Functions like phy_modify_paged() read the current page, on Realtek
> PHY's this means reading the value of register 0x1f. Add special
> handling for reading this register, similar to what we do already
> in r8168g_mdio_write(). Currently we read a random value that by
> chance seems to be 0 always.
> 
> Fixes: a2928d28643e ("r8169: use paged versions of phylib MDIO access functions")
> Signed-off-by: Heiner Kallweit <hkallweit1@gmail.com>

Applied, thanks.

Re: [PATCH net] r8169: fix page read in r8168g_mdio_read

[David Miller]

From: David Miller <davem@davemloft.net>
Date: Wed, 06 Nov 2019 21:37:58 -0800 (PST)

> From: Heiner Kallweit <hkallweit1@gmail.com>
> Date: Wed, 6 Nov 2019 21:51:31 +0100
> 
>> Functions like phy_modify_paged() read the current page, on Realtek
>> PHY's this means reading the value of register 0x1f. Add special
>> handling for reading this register, similar to what we do already
>> in r8168g_mdio_write(). Currently we read a random value that by
>> chance seems to be 0 always.
>> 
>> Fixes: a2928d28643e ("r8169: use paged versions of phylib MDIO access functions")
>> Signed-off-by: Heiner Kallweit <hkallweit1@gmail.com>
> 
> Applied, thanks.

And also queued up for -stable :-)