[PATCH v2] net: bcmgenet: Fix attaching to PYH failed on RPi 4B

[Jian-Hong Pan <jhp@endlessos.org>]

The Broadcom UniMAC MDIO bus from mdio-bcm-unimac module comes too late.
So, GENET cannot find the ethernet PHY on UniMAC MDIO bus. This leads
GENET fail to attach the PHY as following log:

bcmgenet fd580000.ethernet: GENET 5.0 EPHY: 0x0000
...
could not attach to PHY
bcmgenet fd580000.ethernet eth0: failed to connect to PHY
uart-pl011 fe201000.serial: no DMA platform data
libphy: bcmgenet MII bus: probed
...
unimac-mdio unimac-mdio.-19: Broadcom UniMAC MDIO bus

This patch adds the soft dependency to load mdio-bcm-unimac module
before genet module to avoid the issue.

Buglink: https://bugzilla.kernel.org/show_bug.cgi?id=213485
Signed-off-by: Jian-Hong Pan <jhp@endlessos.org>
---
v2: Load mdio-bcm-unimac before genet module instead of trying to
    connect the PHY in a loop.

 drivers/net/ethernet/broadcom/genet/bcmgenet.c | 1 +
 1 file changed, 1 insertion(+)

diff --git a/drivers/net/ethernet/broadcom/genet/bcmgenet.c b/drivers/net/ethernet/broadcom/genet/bcmgenet.c
index fcca023f22e5..41f7f078cd27 100644
--- a/drivers/net/ethernet/broadcom/genet/bcmgenet.c
+++ b/drivers/net/ethernet/broadcom/genet/bcmgenet.c
@@ -4296,3 +4296,4 @@ MODULE_AUTHOR("Broadcom Corporation");
 MODULE_DESCRIPTION("Broadcom GENET Ethernet controller driver");
 MODULE_ALIAS("platform:bcmgenet");
 MODULE_LICENSE("GPL");
+MODULE_SOFTDEP("pre: mdio-bcm-unimac");
-- 
2.32.0