From: Alexander Dahl <ada@thorsis.com>
To: Claudiu Beznea <claudiu.beznea@tuxon.dev>
Cc: Nicolas Ferre <nicolas.ferre@microchip.com>,
Ryan Wanner <ryan.wanner@microchip.com>,
linux-arm-kernel@lists.infradead.org, devicetree@vger.kernel.org,
linux-clk@vger.kernel.org, linux-kernel@vger.kernel.org,
Srinivas Kandagatla <srinivas.kandagatla@linaro.org>,
Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Subject: [PATCH v2 09/16] nvmem: microchip-otpc: Avoid reading a write-only register
Date: Mon, 10 Feb 2025 17:50:47 +0100 [thread overview]
Message-ID: <20250210165050.496486-1-ada@thorsis.com> (raw)
In-Reply-To: <20250210164506.495747-1-ada@thorsis.com>
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@thorsis.com>
Fixes: 98830350d3fc ("nvmem: microchip-otpc: add support")
---
Notes:
v2:
- Add Fixes tag
- Remove temporary variable usage
- Reword misleading subject (s/writing/reading/)
drivers/nvmem/microchip-otpc.c | 4 +---
1 file changed, 1 insertion(+), 3 deletions(-)
diff --git a/drivers/nvmem/microchip-otpc.c b/drivers/nvmem/microchip-otpc.c
index df979e8549fdb..e2851c63cc0b4 100644
--- a/drivers/nvmem/microchip-otpc.c
+++ b/drivers/nvmem/microchip-otpc.c
@@ -82,9 +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 |= MCHP_OTPC_CR_READ;
- writel_relaxed(tmp, otpc->base + MCHP_OTPC_CR);
+ writel_relaxed(MCHP_OTPC_CR_READ, otpc->base + MCHP_OTPC_CR);
/* Wait for packet to be transferred into temporary buffers. */
return read_poll_timeout(readl_relaxed, tmp, !(tmp & MCHP_OTPC_SR_READ),
--
2.39.5
next prev parent reply other threads:[~2025-02-10 16:50 UTC|newest]
Thread overview: 36+ messages / expand[flat|nested] mbox.gz Atom feed top
2025-02-10 16:44 [PATCH v2 00/16] Microchip OTPC driver on SAM9X60 exposing UIDxR as additional nvmem device Alexander Dahl
2025-02-10 16:44 ` [PATCH v2 01/16] dt-bindings: clock: at91: Split up per SoC partially Alexander Dahl
2025-02-10 17:05 ` Krzysztof Kozlowski
2025-02-11 7:16 ` Alexander Dahl
2025-02-11 7:47 ` Krzysztof Kozlowski
2025-02-17 9:11 ` Claudiu Beznea
2025-02-17 9:47 ` Alexander Dahl
2025-02-19 8:51 ` Claudiu Beznea
2025-02-19 9:08 ` Alexander Dahl
2025-02-10 16:44 ` [PATCH v2 02/16] ARM: dts: microchip: Use new PMC bindings Alexander Dahl
2025-02-10 16:44 ` [PATCH v2 03/16] clk: at91: " Alexander Dahl
2025-02-10 16:44 ` [PATCH v2 04/16] dt-bindings: clock: at91: Allow referencing main rc oscillator in DT Alexander Dahl
2025-02-10 17:07 ` Krzysztof Kozlowski
2025-02-11 7:26 ` Alexander Dahl
2025-02-11 8:01 ` Krzysztof Kozlowski
2025-02-10 16:44 ` [PATCH v2 05/16] clk: at91: Allow enabling main_rc_osc through DT Alexander Dahl
2025-02-10 16:44 ` [PATCH v2 06/16] clk: at91: Add peripheral id for OTPC Alexander Dahl
2025-02-10 16:44 ` [PATCH v2 07/16] dt-bindings: nvmem: microchip-otpc: Add compatible for SAM9X60 Alexander Dahl
2025-02-12 9:13 ` Krzysztof Kozlowski
2025-02-10 16:44 ` [PATCH v2 08/16] dt-bindings: nvmem: microchip-otpc: Add required clocks Alexander Dahl
2025-02-10 16:59 ` Krzysztof Kozlowski
2025-02-11 7:05 ` Alexander Dahl
2025-02-11 7:50 ` Krzysztof Kozlowski
2025-02-10 16:50 ` Alexander Dahl [this message]
2025-02-11 6:47 ` [PATCH v2 09/16] nvmem: microchip-otpc: Avoid reading a write-only register Greg Kroah-Hartman
2025-02-17 9:10 ` Claudiu Beznea
2025-02-11 6:52 ` [PATCH v2 10/16] nvmem: microchip-otpc: Fix swapped 'sleep' and 'timeout' parameters Alexander Dahl
2025-02-11 6:52 ` [PATCH v2 11/16] nvmem: microchip-otpc: Add SAM9X60 support Alexander Dahl
2025-02-11 6:52 ` [PATCH v2 12/16] ARM: dts: microchip: sama7g5: Add OTPC clocks Alexander Dahl
2025-02-17 9:10 ` [PATCH v2 10/16] nvmem: microchip-otpc: Fix swapped 'sleep' and 'timeout' parameters Claudiu Beznea
2025-02-11 6:53 ` [PATCH v2 13/16] ARM: dts: microchip: sam9x60: Add OTPC node Alexander Dahl
2025-02-11 6:53 ` [PATCH v2 14/16] ARM: dts: microchip: sam9x60_curiosity: Enable OTP Controller Alexander Dahl
2025-02-11 6:53 ` [PATCH v2 15/16] nvmem: microchip-otpc: Enable necessary clocks Alexander Dahl
2025-02-17 9:10 ` Claudiu Beznea
2025-02-11 6:53 ` [PATCH v2 16/16] nvmem: microchip-otpc: Expose UID registers as 2nd nvmem device Alexander Dahl
2025-02-17 9:10 ` [PATCH v2 13/16] ARM: dts: microchip: sam9x60: Add OTPC node Claudiu Beznea
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