net: pcs: rzn1-miic: Clear MIIC protection state before unprotect sequence

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On RZ/T2H and RZ/N1D MIIC, writing 0x0000 to the MIIC protection
register clears the protection state machine.

The initial protection state cannot be assumed to be constant,
as it may be influenced by previous activity before the driver
takes ownership of the hardware.

Clear the protection state before issuing the unprotect sequence
so that register access always starts from a known state, regardless
of any previous activity.

Fixes: 7dc54d3b8d ("net: pcs: add Renesas MII converter driver")
Signed-off-by: Yoshihisa Yamamoto <yoshihisa.yamamoto.xn@renesas.com>
Reviewed-by: Lad Prabhakar <prabhakar.mahadev-lad.rj@bp.renesas.com>
Link: https://patch.msgid.link/TYCPR01MB74815955A10817B64BD6FB93A4812@TYCPR01MB7481.jpnprd01.prod.outlook.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

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Yoshihisa Yamamoto 2026-09-24 10:36:57 +00:00 • committed by Jakub Kicinski

parent 38b7c47069

commit 8b99934374

1 changed files with 3 additions and 0 deletions

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drivers/net/pcs/pcs-rzn1-miic.c

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