From mboxrd@z Thu Jan 1 00:00:00 1970 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=-18.7 required=3.0 tests=BAYES_00,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=unavailable 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 87D97C64E7B for ; Wed, 2 Dec 2020 23:01:58 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 3F65022201 for ; Wed, 2 Dec 2020 23:01:58 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2387935AbgLBXBm (ORCPT ); Wed, 2 Dec 2020 18:01:42 -0500 Received: from ssl.serverraum.org ([176.9.125.105]:32859 "EHLO ssl.serverraum.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727557AbgLBXBk (ORCPT ); Wed, 2 Dec 2020 18:01:40 -0500 Received: from apollo.fritz.box (unknown [IPv6:2a02:810c:c200:2e91:6257:18ff:fec4:ca34]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange ECDHE (P-384) server-signature RSA-PSS (2048 bits) server-digest SHA256) (No client certificate requested) by ssl.serverraum.org (Postfix) with ESMTPSA id 76ABC23E5B; Thu, 3 Dec 2020 00:00:58 +0100 (CET) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=walle.cc; s=mail2016061301; t=1606950058; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=tA/aM6lWMfa7TmNVA8dfiG+itOvZgqH1cE8LTQP5Qes=; b=qTIbY8IdbkBb03JKv09ERJyQryGyyn0LDkdFpnZaMzWuFqk2t6yTeC3kokoPU2Hm2619TM FSxUi1G7sy50T/pe3sxBiGBaJD00g/r9bGG7LWzI+Kjo5cDk9XidfGzVCdvjWPWxQ1X9l5 XoSWo0G4Enik+j+L/twUr2sNgVwZy5o= From: Michael Walle To: linux-mtd@lists.infradead.org, linux-kernel@vger.kernel.org Cc: Miquel Raynal , Richard Weinberger , Vignesh Raghavendra , Tudor Ambarus , Boris Brezillon , Michael Walle Subject: [PATCH v7 2/7] mtd: spi-nor: ignore errors in spi_nor_unlock_all() Date: Thu, 3 Dec 2020 00:00:35 +0100 Message-Id: <20201202230040.14009-3-michael@walle.cc> X-Mailer: git-send-email 2.20.1 In-Reply-To: <20201202230040.14009-1-michael@walle.cc> References: <20201202230040.14009-1-michael@walle.cc> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Just try to unlock the whole SPI-NOR flash array. Don't abort the probing in case of an error. Justifications: (1) For some boards, this just works because spi_nor_write_16bit_sr_and_check() is broken and just checks the second half of the 16bit. Once that will be fixed, SPI probe will fail for boards which has hardware-write protected SPI-NOR flashes. (2) Until now, hardware write-protection was the only viable solution to use the block protection bits. This is because this very function spi_nor_unlock_all() will be called unconditionally on every linux boot. Therefore, this bits only makes sense in combination with the hardware write-protection. If we would fail the SPI probe on an error in spi_nor_unlock_all() we'd break virtually all users of the block protection bits. (3) We should try hard to keep the MTD working even if the flash might not be writable/erasable. Fixes: 3e0930f109e7 ("mtd: spi-nor: Rework the disabling of block write protection") Signed-off-by: Michael Walle --- changes since v6: - new patch drivers/mtd/spi-nor/core.c | 23 +++++++++++++---------- 1 file changed, 13 insertions(+), 10 deletions(-) diff --git a/drivers/mtd/spi-nor/core.c b/drivers/mtd/spi-nor/core.c index 5bee7c8da4dc..013198abe929 100644 --- a/drivers/mtd/spi-nor/core.c +++ b/drivers/mtd/spi-nor/core.c @@ -3121,20 +3121,27 @@ static int spi_nor_quad_enable(struct spi_nor *nor) } /** - * spi_nor_unlock_all() - Unlocks the entire flash memory array. + * spi_nor_try_unlock_all() - Tries to unlock the entire flash memory array. * @nor: pointer to a 'struct spi_nor'. * * Some SPI NOR flashes are write protected by default after a power-on reset * cycle, in order to avoid inadvertent writes during power-up. Backward * compatibility imposes to unlock the entire flash memory array at power-up * by default. + * + * Unprotecting the entire flash array will fail for boards which are hardware + * write-protected. Thus any errors are ignored. */ -static int spi_nor_unlock_all(struct spi_nor *nor) +static void spi_nor_try_unlock_all(struct spi_nor *nor) { - if (nor->flags & SNOR_F_HAS_LOCK) - return spi_nor_unlock(&nor->mtd, 0, nor->params->size); + int ret; - return 0; + if (!(nor->flags & SNOR_F_HAS_LOCK)) + return; + + ret = spi_nor_unlock(&nor->mtd, 0, nor->params->size); + if (ret) + dev_dbg(nor->dev, "Failed to unlock the entire flash memory array\n"); } static int spi_nor_init(struct spi_nor *nor) @@ -3153,11 +3160,7 @@ static int spi_nor_init(struct spi_nor *nor) return err; } - err = spi_nor_unlock_all(nor); - if (err) { - dev_dbg(nor->dev, "Failed to unlock the entire flash memory array\n"); - return err; - } + spi_nor_try_unlock_all(nor); if (nor->addr_width == 4 && nor->read_proto != SNOR_PROTO_8_8_8_DTR && -- 2.20.1