linux-kernel - [PATCH v1 01/12] nvmem: microchip-otpc: Avoid writing a write-only register

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Message-Id: <20240821105943.230281-2-ada@thorsis.com>
Date: Wed, 21 Aug 2024 12:59:32 +0200
From: Alexander Dahl <ada@...rsis.com>
To: Claudiu Beznea <claudiu.beznea@...on.dev>
Cc: Christian Melki <christian.melki@...ata.com>,
	Srinivas Kandagatla <srinivas.kandagatla@...aro.org>,
	linux-arm-kernel@...ts.infradead.org (moderated list:MICROCHIP OTPC DRIVER),
	linux-kernel@...r.kernel.org (open list)
Subject: [PATCH v1 01/12] nvmem: microchip-otpc: Avoid writing a write-only register

The OTPC Control Register (OTPC_CR) has just write-only members.
Reading from that register leads to a warning in OTPC Write Protection
Status Register (OTPC_WPSR) in field Software Error Type (SWETYP) of
type READ_WO (A write-only register has been read (warning).)

Just create the register write content from scratch is sufficient here.

Signed-off-by: Alexander Dahl <ada@...rsis.com>
---
 drivers/nvmem/microchip-otpc.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/nvmem/microchip-otpc.c b/drivers/nvmem/microchip-otpc.c
index 7cf81738a3e0..03e60b99f2c9 100644
--- a/drivers/nvmem/microchip-otpc.c
+++ b/drivers/nvmem/microchip-otpc.c
@@ -82,7 +82,7 @@ static int mchp_otpc_prepare_read(struct mchp_otpc *otpc,
 	writel_relaxed(tmp, otpc->base + MCHP_OTPC_MR);
 
 	/* Set read. */
-	tmp = readl_relaxed(otpc->base + MCHP_OTPC_CR);
+	tmp = 0;
 	tmp |= MCHP_OTPC_CR_READ;
 	writel_relaxed(tmp, otpc->base + MCHP_OTPC_CR);
 
-- 
2.39.2