From patchwork Mon May 31 18:17:53 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Pratyush Yadav X-Patchwork-Id: 450673 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-19.1 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_CR_TRAILER, INCLUDES_PATCH, MAILING_LIST_MULTI, SPF_HELO_NONE, SPF_PASS, URIBL_BLOCKED, USER_AGENT_GIT autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id D7ABEC47082 for ; Mon, 31 May 2021 18:18:35 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id BB8C76124B for ; Mon, 31 May 2021 18:18:35 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232062AbhEaSUI (ORCPT ); Mon, 31 May 2021 14:20:08 -0400 Received: from fllv0015.ext.ti.com ([198.47.19.141]:59200 "EHLO fllv0015.ext.ti.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230351AbhEaSUE (ORCPT ); Mon, 31 May 2021 14:20:04 -0400 Received: from lelv0266.itg.ti.com ([10.180.67.225]) by fllv0015.ext.ti.com (8.15.2/8.15.2) with ESMTP id 14VII83s078813; Mon, 31 May 2021 13:18:08 -0500 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=ti.com; s=ti-com-17Q1; t=1622485088; bh=moH2ZY+xmI5k70xNoKzxtoVfAjiFgQzTAD/mpB3NYvw=; h=From:To:Subject:Date:In-Reply-To:References; b=PfRJmqmAUyqOuPK2Jt1RKEtjynUr3xOi3nROnR0HbgKbfM9XICfYv8yQ8gvV76PYi +3i8bj0pCJD9hoGwGoQVr+6tKhAPqWKWiL6yPeMibtRqmJQNvMwpxaYvY8SJPq+gCt QNr1PkLmA6sXlOnfdukvcFAmBe9oJ2gnEz4/EMI8= Received: from DLEE100.ent.ti.com (dlee100.ent.ti.com [157.170.170.30]) by lelv0266.itg.ti.com (8.15.2/8.15.2) with ESMTPS id 14VII8Yo027498 (version=TLSv1.2 cipher=AES256-GCM-SHA384 bits=256 verify=FAIL); Mon, 31 May 2021 13:18:08 -0500 Received: from DLEE100.ent.ti.com (157.170.170.30) by DLEE100.ent.ti.com (157.170.170.30) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA256_P256) id 15.1.2176.2; Mon, 31 May 2021 13:18:08 -0500 Received: from fllv0039.itg.ti.com (10.64.41.19) by DLEE100.ent.ti.com (157.170.170.30) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA256_P256) id 15.1.2176.2 via Frontend Transport; Mon, 31 May 2021 13:18:08 -0500 Received: from pratyush-OptiPlex-790.dhcp.ti.com (ileax41-snat.itg.ti.com [10.172.224.153]) by fllv0039.itg.ti.com (8.15.2/8.15.2) with ESMTP id 14VIHwdH118543; Mon, 31 May 2021 13:18:05 -0500 From: Pratyush Yadav To: Tudor Ambarus , Michael Walle , Pratyush Yadav , Miquel Raynal , Richard Weinberger , Vignesh Raghavendra , Mark Brown , , , Subject: [PATCH v2 2/6] mtd: spi-nor: spansion: write 2 bytes when disabling Octal DTR mode Date: Mon, 31 May 2021 23:47:53 +0530 Message-ID: <20210531181757.19458-3-p.yadav@ti.com> X-Mailer: git-send-email 2.30.0 In-Reply-To: <20210531181757.19458-1-p.yadav@ti.com> References: <20210531181757.19458-1-p.yadav@ti.com> MIME-Version: 1.0 X-EXCLAIMER-MD-CONFIG: e1e8a2fd-e40a-4ac6-ac9b-f7e9cc9ee180 Precedence: bulk List-ID: X-Mailing-List: linux-spi@vger.kernel.org The Octal DTR configuration is stored in the CFR5V register. This register is 1 byte wide. But 1 byte long transactions are not allowed in 8D-8D-8D mode. Since the next byte address does not contain any register, it is safe to write any value to it. Write a 0 to it. Signed-off-by: Pratyush Yadav --- (no changes since v1) drivers/mtd/spi-nor/spansion.c | 18 +++++++++++++----- 1 file changed, 13 insertions(+), 5 deletions(-) diff --git a/drivers/mtd/spi-nor/spansion.c b/drivers/mtd/spi-nor/spansion.c index ee82dcd75310..e6bf5c9eee6a 100644 --- a/drivers/mtd/spi-nor/spansion.c +++ b/drivers/mtd/spi-nor/spansion.c @@ -65,10 +65,18 @@ static int spi_nor_cypress_octal_dtr_enable(struct spi_nor *nor, bool enable) if (ret) return ret; - if (enable) - *buf = SPINOR_REG_CYPRESS_CFR5V_OCT_DTR_EN; - else - *buf = SPINOR_REG_CYPRESS_CFR5V_OCT_DTR_DS; + if (enable) { + buf[0] = SPINOR_REG_CYPRESS_CFR5V_OCT_DTR_EN; + } else { + /* + * The register is 1-byte wide, but 1-byte transactions are not + * allowed in 8D-8D-8D mode. Since there is no register at the + * next location, just initialize the value to 0 and let the + * transaction go on. + */ + buf[0] = SPINOR_REG_CYPRESS_CFR5V_OCT_DTR_DS; + buf[1] = 0; + } op = (struct spi_mem_op) SPI_MEM_OP(SPI_MEM_OP_CMD(SPINOR_OP_WR_ANY_REG, 1), @@ -76,7 +84,7 @@ static int spi_nor_cypress_octal_dtr_enable(struct spi_nor *nor, bool enable) SPINOR_REG_CYPRESS_CFR5V, 1), SPI_MEM_OP_NO_DUMMY, - SPI_MEM_OP_DATA_OUT(1, buf, 1)); + SPI_MEM_OP_DATA_OUT(enable ? 1 : 2, buf, 1)); if (!enable) spi_nor_spimem_setup_op(nor, &op, SNOR_PROTO_8_8_8_DTR);