From patchwork Mon May 10 10:18:34 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Greg KH X-Patchwork-Id: 433831 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=-19.4 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, 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 7FCF5C2BA02 for ; Mon, 10 May 2021 11:02:32 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 68E58619C4 for ; Mon, 10 May 2021 11:02:32 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S234115AbhEJLCM (ORCPT ); Mon, 10 May 2021 07:02:12 -0400 Received: from mail.kernel.org ([198.145.29.99]:52682 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S234700AbhEJK4x (ORCPT ); Mon, 10 May 2021 06:56:53 -0400 Received: by mail.kernel.org (Postfix) with ESMTPSA id 288CF619B5; Mon, 10 May 2021 10:48:27 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1620643707; bh=wLgsYTeYI0/bP3368111EJiA4JNU8ZKsRJQkJqT3jaU=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=yGr/sJWBtk89/GUOnujNbOyp7aGzsRQCiw95i6Kk5vROHwix+bgvzGM2Pdfvaxkn2 Qg5fTPnr6MTtudu3ozseO5rTiVRWOOzxIQrtFLewA2hyu8m4iKpWiZXlgx522/dq3T 4JzFifqdMYblTedLOubAFmWQ2LC7yvU6UftfTEMo= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, David Bauer , Mark Brown , Sasha Levin Subject: [PATCH 5.11 124/342] spi: sync up initial chipselect state Date: Mon, 10 May 2021 12:18:34 +0200 Message-Id: <20210510102014.179799693@linuxfoundation.org> X-Mailer: git-send-email 2.31.1 In-Reply-To: <20210510102010.096403571@linuxfoundation.org> References: <20210510102010.096403571@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org From: David Bauer [ Upstream commit d347b4aaa1a042ea528e385d9070b74c77a14321 ] When initially probing the SPI slave device, the call for disabling an SPI device without the SPI_CS_HIGH flag is not applied, as the condition for checking whether or not the state to be applied equals the one currently set evaluates to true. This however might not necessarily be the case, as the chipselect might be active. Add a force flag to spi_set_cs which allows to override this early exit condition. Set it to false everywhere except when called from spi_setup to sync up the initial CS state. Fixes commit d40f0b6f2e21 ("spi: Avoid setting the chip select if we don't need to") Signed-off-by: David Bauer Link: https://lore.kernel.org/r/20210416195956.121811-1-mail@david-bauer.net Signed-off-by: Mark Brown Signed-off-by: Sasha Levin --- drivers/spi/spi.c | 16 ++++++++-------- 1 file changed, 8 insertions(+), 8 deletions(-) diff --git a/drivers/spi/spi.c b/drivers/spi/spi.c index ccca3a7409fa..6f81a3c4c7e0 100644 --- a/drivers/spi/spi.c +++ b/drivers/spi/spi.c @@ -795,7 +795,7 @@ int spi_register_board_info(struct spi_board_info const *info, unsigned n) /*-------------------------------------------------------------------------*/ -static void spi_set_cs(struct spi_device *spi, bool enable) +static void spi_set_cs(struct spi_device *spi, bool enable, bool force) { bool enable1 = enable; @@ -803,7 +803,7 @@ static void spi_set_cs(struct spi_device *spi, bool enable) * Avoid calling into the driver (or doing delays) if the chip select * isn't actually changing from the last time this was called. */ - if ((spi->controller->last_cs_enable == enable) && + if (!force && (spi->controller->last_cs_enable == enable) && (spi->controller->last_cs_mode_high == (spi->mode & SPI_CS_HIGH))) return; @@ -1251,7 +1251,7 @@ static int spi_transfer_one_message(struct spi_controller *ctlr, struct spi_statistics *statm = &ctlr->statistics; struct spi_statistics *stats = &msg->spi->statistics; - spi_set_cs(msg->spi, true); + spi_set_cs(msg->spi, true, false); SPI_STATISTICS_INCREMENT_FIELD(statm, messages); SPI_STATISTICS_INCREMENT_FIELD(stats, messages); @@ -1319,9 +1319,9 @@ fallback_pio: &msg->transfers)) { keep_cs = true; } else { - spi_set_cs(msg->spi, false); + spi_set_cs(msg->spi, false, false); _spi_transfer_cs_change_delay(msg, xfer); - spi_set_cs(msg->spi, true); + spi_set_cs(msg->spi, true, false); } } @@ -1330,7 +1330,7 @@ fallback_pio: out: if (ret != 0 || !keep_cs) - spi_set_cs(msg->spi, false); + spi_set_cs(msg->spi, false, false); if (msg->status == -EINPROGRESS) msg->status = ret; @@ -3410,11 +3410,11 @@ int spi_setup(struct spi_device *spi) */ status = 0; - spi_set_cs(spi, false); + spi_set_cs(spi, false, true); pm_runtime_mark_last_busy(spi->controller->dev.parent); pm_runtime_put_autosuspend(spi->controller->dev.parent); } else { - spi_set_cs(spi, false); + spi_set_cs(spi, false, true); } mutex_unlock(&spi->controller->io_mutex);