From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature ECDSA (prime256v1) server-digest SHA256) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 01B78606D81B for ; Thu, 5 Nov 2026 12:09:43 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key, unprotected) header.d=lists.infradead.org header.i=@lists.infradead.org header.a=rsa-sha256 header.s=bombadil.20210309 header.b=2PNVsbrz; dkim=pass (2048-bit key, unprotected) header.d=thorsis.com header.i=@thorsis.com header.a=rsa-sha256 header.s=dkim header.b=mgJMCC8V DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender:List-Subscribe:List-Help :List-Post:List-Archive:List-Unsubscribe:List-Id:Content-Transfer-Encoding: MIME-Version:References:In-Reply-To:Message-ID:Date:Subject:Cc:To:From: Reply-To:Content-Type:Content-ID:Content-Description:Resent-Date:Resent-From: Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Unsubscribe-Post: List-Owner; bh=+zy6lijmScjxOAMWEF8MrPaSb7OpuW14nYg2KILAhV0=; b=2PNVsbrznbPfoc VvfvVxsnnzlDgd1dm5mve2L+m38DdV/pQ8IQ8qjd1BiNjeoHZVN0KG1/c3M287EaiqZrbuekVD86C enLN6bPKRNQmsxyXm4/HTweETPedXSq7OhjrGRyrkbVNBh4sqI+iO7yRPJZNV+iqPRv2e+SKWAcXz BKgWHJdZAFkzCABfOozfflK8RBQcQJ+etW9x4AWALQLFPxpIIt79UzUaMlXS4XrJsy2fFQ90hdKNd zB8h0dstftOOo88zsHhOYNBjs0OnhBshLdRLW1qh9bY+p8osJ4s0FTYG4XyJsnI06z7CidKyjUglM mNRYqA30dptYIzDNR/3Q==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.100.1 #2 (Red Hat Linux)) id 1xOwHd-00000008qXX-1GIj; Thu, 05 Nov 2026 12:09:36 +0000 Received: from mail.thorsis.com ([2003:a:e28:26e4::10]) by bombadil.infradead.org with esmtps (Exim 4.100.1 #2 (Red Hat Linux)) id 1xOwHW-00000008qRe-1U4K for linux-arm-kernel@lists.infradead.org; Thu, 05 Nov 2026 12:09:29 +0000 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-Archived-By: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Last-TLS-Session-Version: TLSv1.3 X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.9.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20261105_040927_738577_446BF5AE X-CRM114-Status: GOOD ( 10.43 ) X-Spam-Score: -2.1 (--) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "linux-arm-kernel" X-Spam-Status: No, score=-18.9 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,DKIM_VALID_EF, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,USER_AGENT_GIT autolearn=ham autolearn_force=no version=4.0.1 X-Spam-Checker-Version: SpamAssassin 4.0.1 (2024-03-26) on aws-us-west-2-korg-listserv-alma10-1 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