[PATCH v1] lan743x: correctly handle chips with internal PHY

From: Sven Van Asbroeck
Date: Wed Nov 04 2020 - 11:08:55 EST


Commit 6f197fb63850 ("lan743x: Added fixed link and RGMII support")
assumes that chips with an internal PHY will not have a devicetree
entry. This is incorrect: even for these chips, a devicetree entry
can be useful e.g. to pass the mac address from bootloader to chip:

&pcie {
status = "okay";

host@0 {
reg = <0 0 0 0 0>;

#address-cells = <3>;
#size-cells = <2>;

lan7430: ethernet@0 {
/* LAN7430 with internal PHY */
compatible = "microchip,lan743x";
status = "okay";
reg = <0 0 0 0 0>;
/* filled in by bootloader */
local-mac-address = [00 00 00 00 00 00];
};
};
};

If a devicetree entry is present, the driver will not attach the chip
to its internal phy, and the chip will be non-operational.

Fix by tweaking the phy connection algorithm:
- first try to connect to a phy specified in the devicetree
(could be 'real' phy, or just a 'fixed-link')
- if that doesn't succeed, try to connect to an internal phy, even
if the chip has a devnode

This method no longer explicitly exposes the phy mode, but we can
get around that by querying the phy mode from the phydev. The
phy_mode member in the adapter private struct can then be removed.

Note that as a side-effect, the devicetree phy mode now no longer
has a default, and always needs to be specified explicitly (via
'phy-connection-type').

Tested on a LAN7430 with internal PHY. I cannot test a device using
fixed-link, as I do not have access to one.

Fixes: 6f197fb63850 ("lan743x: Added fixed link and RGMII support")
Tested-by: Sven Van Asbroeck <TheSven73@xxxxxxxxx> # lan7430
Signed-off-by: Sven Van Asbroeck <TheSven73@xxxxxxxxx>
---

Tree: v5.10-rc2

To: Bryan Whitehead <bryan.whitehead@xxxxxxxxxxxxx>
To: "David S. Miller" <davem@xxxxxxxxxxxxx>
To: Jakub Kicinski <kuba@xxxxxxxxxx>
Cc: Microchip Linux Driver Support <UNGLinuxDriver@xxxxxxxxxxxxx>
Cc: Andrew Lunn <andrew@xxxxxxx>
Cc: Roelof Berg <rberg@xxxxxxxxxxxxxxxxx>
Cc: netdev@xxxxxxxxxxxxxxx
Cc: linux-kernel@xxxxxxxxxxxxxxx

drivers/net/ethernet/microchip/lan743x_main.c | 32 ++++++-------------
drivers/net/ethernet/microchip/lan743x_main.h | 1 -
2 files changed, 9 insertions(+), 24 deletions(-)

diff --git a/drivers/net/ethernet/microchip/lan743x_main.c b/drivers/net/ethernet/microchip/lan743x_main.c
index f2d13e8d20f0..eb990e036611 100644
--- a/drivers/net/ethernet/microchip/lan743x_main.c
+++ b/drivers/net/ethernet/microchip/lan743x_main.c
@@ -957,7 +957,7 @@ static void lan743x_phy_link_status_change(struct net_device *netdev)
data = lan743x_csr_read(adapter, MAC_CR);

/* set interface mode */
- if (phy_interface_mode_is_rgmii(adapter->phy_mode))
+ if (phy_interface_is_rgmii(phydev))
/* RGMII */
data &= ~MAC_CR_MII_EN_;
else
@@ -1021,34 +1021,19 @@ static int lan743x_phy_open(struct lan743x_adapter *adapter)

netdev = adapter->netdev;
phynode = of_node_get(adapter->pdev->dev.of_node);
- adapter->phy_mode = PHY_INTERFACE_MODE_GMII;
-
- if (phynode) {
- of_get_phy_mode(phynode, &adapter->phy_mode);
-
- if (of_phy_is_fixed_link(phynode)) {
- ret = of_phy_register_fixed_link(phynode);
- if (ret) {
- netdev_err(netdev,
- "cannot register fixed PHY\n");
- of_node_put(phynode);
- goto return_error;
- }
- }
- phydev = of_phy_connect(netdev, phynode,
- lan743x_phy_link_status_change, 0,
- adapter->phy_mode);
- of_node_put(phynode);
- if (!phydev)
- goto return_error;
- } else {
+
+ /* try devicetree phy, or fixed link */
+ phydev = of_phy_get_and_connect(netdev, phynode,
+ lan743x_phy_link_status_change);
+ if (!phydev) {
+ /* try internal PHY */
phydev = phy_find_first(adapter->mdiobus);
if (!phydev)
goto return_error;

ret = phy_connect_direct(netdev, phydev,
lan743x_phy_link_status_change,
- adapter->phy_mode);
+ PHY_INTERFACE_MODE_GMII);
if (ret)
goto return_error;
}
@@ -1063,6 +1048,7 @@ static int lan743x_phy_open(struct lan743x_adapter *adapter)

phy_start(phydev);
phy_start_aneg(phydev);
+ phy_attached_info(phydev);
return 0;

return_error:
diff --git a/drivers/net/ethernet/microchip/lan743x_main.h b/drivers/net/ethernet/microchip/lan743x_main.h
index a536f4a4994d..3a0e70daa88f 100644
--- a/drivers/net/ethernet/microchip/lan743x_main.h
+++ b/drivers/net/ethernet/microchip/lan743x_main.h
@@ -703,7 +703,6 @@ struct lan743x_rx {
struct lan743x_adapter {
struct net_device *netdev;
struct mii_bus *mdiobus;
- phy_interface_t phy_mode;
int msg_enable;
#ifdef CONFIG_PM
u32 wolopts;
--
2.17.1