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=-9.1 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI, SIGNED_OFF_BY,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 1FC78C43381 for ; Sat, 23 Feb 2019 08:51:20 +0000 (UTC) Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id DBFBE20684 for ; Sat, 23 Feb 2019 08:51:19 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=lists.infradead.org header.i=@lists.infradead.org header.b="H0+O9ACy" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org DBFBE20684 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=martin.sperl.org Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-arm-kernel-bounces+infradead-linux-arm-kernel=archiver.kernel.org@lists.infradead.org DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20170209; h=Sender: Content-Transfer-Encoding:Content-Type:MIME-Version:Cc:List-Subscribe: List-Help:List-Post:List-Archive:List-Unsubscribe:List-Id:References: In-Reply-To:Message-Id:Date:Subject:To:From:Reply-To:Content-ID: Content-Description:Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc :Resent-Message-ID:List-Owner; bh=LVTZhdLNNvqnJdXfq/Prypbs54vKJ0qBmkmn2hXouKY=; b=H0+O9ACyZHBGjs2tC4bkz7iFZr reoIAe+kV1vugg6dliR3B/+R7PkxcpJUSvKpokW4M3NBDXS7m/lWbkyxmCDjNUGkDYyqGWGS53dEu OjZPZyDv4Eq93cYd61cn1lw4pyVzUYwKk1NdlwmFqbivLY56Ih098yVr8lTnx1roZqffTn7MPucJ3 MaDZhkBrtivivwKFTllEPVmb6+i5p2ICj/rdZ7dJ4FXtCbqwWKc4iCHo0Gk11W/nHwqYnFe9v3KUK KJPrWIOOg6aiwNDPZfi8uVxXYs7fDi0z4I+rjfDLmQsl/v+DYjs7QMukUUAfz+txssmdH9Ep4Tot2 4XoHRyxQ==; Received: from localhost ([127.0.0.1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.90_1 #2 (Red Hat Linux)) id 1gxT1c-0002Fy-5Z; Sat, 23 Feb 2019 08:51:12 +0000 Received: from 212-186-180-163.static.upcbusiness.at ([212.186.180.163] helo=cgate.sperl.org) by bombadil.infradead.org with esmtp (Exim 4.90_1 #2 (Red Hat Linux)) id 1gxT14-0001PS-DD; Sat, 23 Feb 2019 08:50:42 +0000 Received: from hc1.intern.sperl.org (account martin@sperl.org [10.10.10.59] verified) by sperl.org (CommuniGate Pro SMTP 6.2.1 _community_) with ESMTPSA id 7757393; Sat, 23 Feb 2019 08:50:05 +0000 From: kernel@martin.sperl.org To: Mark Brown , Eric Anholt , Stefan Wahren , linux-spi@vger.kernel.org, linux-rpi-kernel@lists.infradead.org, linux-arm-kernel@lists.infradead.org Subject: [PATCH 3/5] spi: core: allow defining time that cs is deasserted as a multiple of SCK Date: Sat, 23 Feb 2019 08:49:50 +0000 Message-Id: <20190223084952.14758-4-kernel@martin.sperl.org> X-Mailer: git-send-email 2.11.0 In-Reply-To: <20190223084952.14758-1-kernel@martin.sperl.org> References: <20190223084952.14758-1-kernel@martin.sperl.org> X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20190223_005039_343676_C9355E63 X-CRM114-Status: UNSURE ( 8.84 ) X-CRM114-Notice: Please train this message. X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.21 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Martin Sperl MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+infradead-linux-arm-kernel=archiver.kernel.org@lists.infradead.org From: Martin Sperl Support setting a delay between cs assert and deassert as a multiple of spi clock length. Signed-off-by: Martin Sperl --- drivers/spi/spi.c | 8 ++++++++ include/linux/spi/spi.h | 1 + 2 files changed, 9 insertions(+) diff --git a/drivers/spi/spi.c b/drivers/spi/spi.c index 5a4616894d57..d5259bdd4b88 100644 --- a/drivers/spi/spi.c +++ b/drivers/spi/spi.c @@ -1092,6 +1092,7 @@ static void _spi_transfer_cs_change_delay(struct spi_message *msg, { u32 delay = xfer->cs_change_delay; u32 unit = xfer->cs_change_delay_unit; + u32 hz; /* return early on "fast" mode - for everything but USECS */ if (!delay && unit != SPI_DELAY_UNIT_USECS) @@ -1107,6 +1108,13 @@ static void _spi_transfer_cs_change_delay(struct spi_message *msg, break; case SPI_DELAY_UNIT_NSECS: /* nothing to do here */ break; + case SPI_DELAY_UNIT_SCK: + /* if there is no effective speed know, then approximate + * by underestimating with half the requested hz + */ + hz = xfer->effective_speed_hz ?: xfer->speed_hz / 2; + delay *= DIV_ROUND_UP(1000000000, hz); + break; default: dev_err_once(&msg->spi->dev, "Use of unsupported delay unit %i, using default of 10us\n", diff --git a/include/linux/spi/spi.h b/include/linux/spi/spi.h index f503a712423d..0b1d5e2b8b8b 100644 --- a/include/linux/spi/spi.h +++ b/include/linux/spi/spi.h @@ -799,6 +799,7 @@ struct spi_transfer { u8 cs_change_delay_unit; #define SPI_DELAY_UNIT_USECS 0 #define SPI_DELAY_UNIT_NSECS 1 +#define SPI_DELAY_UNIT_SCK 2 u32 speed_hz; u16 word_delay; -- 2.11.0 _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel