From mboxrd@z Thu Jan 1 00:00:00 1970 Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.remote-ip=217.92.40.78 ARC-Seal: i=1; d=subspace.kernel.org; s=arc20261015; a=rsa-sha256; cv=none; t=1793880566; b=bMPwxG1ODLlj0yTNXbfJQvmewNs2BJnXxLaLT5PrzHPDQq0KNr2In4EYlXsn+iCCVz9X 8wAY+KQEa7dESlTXYzvF2L+FgUfpfvvVjphlcBSZLa+FR2UaNmfJSdvS+9kG+9vsE6/51 ys69uMfkp0fBhbc1Rk+JaZlW/jmh1CwWIE3KotCVJYUdqhVGhFgZrmKPtdxOsCjTF2Xy6 OkD1TZ/FwpQNrMJYic3ja12Qxfk/dCEShUOcVy91zcnT9Ms1ENziucEB7me8ZLGergFDz X//+dcZqB0MAT7xy4BAadfFdEfBHInPiILebVsB96eFJwcyvggT/49ns4XU3vMz+d/A== ARC-Message-Signature: i=1; d=subspace.kernel.org; s=arc20261015; a=rsa-sha256; c=relaxed/relaxed; t=1793880566; h=DMARC-Filter:Received:DKIM-Signature:From:To:Cc:Subject:Date: Message-ID:X-Mailer:In-Reply-To:References:MIME-Version: Content-Transfer-Encoding:X-Last-TLS-Session-Version; bh=+zy6lijmScjxOAMWEF8MrPaSb7OpuW14nYg2KILAhV0=; b=hhZEcaGfL2cAtY4hgg+2W2+qr0usCNzqBcmRNYKT+dwNN30xE1BJSAdynHZ4ib2dpuyL HoIRPApV8fI/0ou342DGatNMq3g/koQ89FcukiUAl1DJf/iH+485GyXZYJxamjdA+09gW S2a2efX+Wz6rTudhEEjUuuMPXpp5rzrzY8t4SCAZdG0eaTOLI2XUtRDtpDPRY6qm+7kaf 0/i384iUePpFV9p5h4w5EtZArLqVeseyszUfjKtq0vFJm2A7wNwsU+vBQlmZjtoQl9wj/ wf78iV1ZVto3E3m5QJYYR8SYnMQQQNBaapoVEhg3ghHRE/rV0XIvRWAxxvJwO9BZs1w== ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass header.from=thorsis.com; spf=pass smtp.mailfrom=thorsis.com; dkim=pass header.d=thorsis.com header.i=@thorsis.com header.a=rsa-sha256 header.s=dkim header.b=mgJMCC8V; arc=none smtp.remote-ip=217.92.40.78 Received: from mail.thorsis.com (mail.thorsis.com [217.92.40.78]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature ECDSA (prime256v1)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id E78FE606D804; Thu, 5 Nov 2026 12:09:25 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.4.2 smtp.subspace.kernel.org E78FE606D804 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=quarantine dis=none) header.from=thorsis.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=thorsis.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key, unprotected) header.d=thorsis.com header.i=@thorsis.com header.a=rsa-sha256 header.s=dkim header.b=mgJMCC8V Received: from [127.0.0.1] (localhost [127.0.0.1]) by localhost (Mailerdaemon) with ESMTPSA id 5363814966AD; Thu, 05 Nov 2026 13:09:59 +0100 (CET) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=thorsis.com; s=dkim; t=1793880599; h=from:subject:date:message-id:to:cc:mime-version: content-transfer-encoding:in-reply-to:references; bh=+zy6lijmScjxOAMWEF8MrPaSb7OpuW14nYg2KILAhV0=; b=mgJMCC8V1e0Z9bWdBiraqhChx35xPFncQMYtijgBslTztVMd0s5ByewH34RJeLOU4wmPFE tXSk7mddxTl1U2Y0NKRWKnaVfHzMvJU2oYqa7TZNWmkphmVNTgmRGFjL1AVL2NilABf5Um 0m1tD1jgW8udbcA2twbwtWDvSIDuyE5SwyaTXV/tutL42h/p096C8WcF90771dkFJuv4/Q hKDlRsZJ51Tbz4OIC5qPwPmI70wPrHpYdmctL25VNN+N8uwoQlJuZ9yqDl0DVGtJLyBbeS YCk9Pv7fqJATWOQCvQPB1Tx4lUd45YJ5p5kVjqyKkTm9dAASbS8P/H4RlwcHOQ== From: Alexander Dahl To: Claudiu Beznea Cc: Nicolas Ferre , Alexandre Belloni , Ryan Wanner , linux-arm-kernel@lists.infradead.org, devicetree@vger.kernel.org, linux-kernel@vger.kernel.org, linux-clk@vger.kernel.org, stable@vger.kernel.org, Srinivas Kandagatla , Greg Kroah-Hartman Subject: [PATCH v4 08/16] nvmem: microchip-otpc: Avoid reading a write-only register Date: Thu, 5 Nov 2026 12:06:44 +0100 Message-ID: <20261105110715.2486432-9-ada@thorsis.com> X-Mailer: git-send-email 2.47.3 In-Reply-To: <20261105110715.2486432-1-ada@thorsis.com> References: <20261105110715.2486432-1-ada@thorsis.com> X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Post: List-Help: List-Subscribe: List-Unsubscribe: List-Owner: Precedence: list MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Last-TLS-Session-Version: TLSv1.3 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. Fixes: 98830350d3fc ("nvmem: microchip-otpc: add support") Cc: stable@vger.kernel.org Reviewed-by: Claudiu Beznea Signed-off-by: Alexander Dahl --- Notes: v4: - Add Reviewed-by tag (thanks Claudiu) v3: - Reorder tags - Add stable tag 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), -- 2.47.3