From patchwork Tue Apr 10 22:44:34 2018 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Boris Brezillon X-Patchwork-Id: 896969 Return-Path: X-Original-To: incoming@patchwork.ozlabs.org Delivered-To: patchwork-incoming@bilbo.ozlabs.org Authentication-Results: ozlabs.org; spf=none (mailfrom) smtp.mailfrom=lists.infradead.org (client-ip=2607:7c80:54:e::133; helo=bombadil.infradead.org; envelope-from=linux-mtd-bounces+incoming=patchwork.ozlabs.org@lists.infradead.org; receiver=) Authentication-Results: ozlabs.org; dmarc=none (p=none dis=none) header.from=bootlin.com Authentication-Results: ozlabs.org; dkim=pass (2048-bit key; unprotected) header.d=lists.infradead.org header.i=@lists.infradead.org header.b="gqxwspPE"; dkim-atps=neutral Received: from bombadil.infradead.org (bombadil.infradead.org [IPv6:2607:7c80:54:e::133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by ozlabs.org (Postfix) with ESMTPS id 40LMm361F0z9s0n for ; Wed, 11 Apr 2018 08:48:51 +1000 (AEST) 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=DYyJGlqAuc3ZCd5nN03oZTgonq6TG6QidZhkrlp9SQU=; b=gqxwspPEA4g2Oinkl/tC03401n o6H/n0CDjqmK7CrujFG6a8m7uBXWPCuSL+H3ZqG8Q+3dXfei+aFUOKV44t47XB1BRcSuolV/Ao0m+ 8McAQvPC6a6/YNTi03njbiXgp46ggrK00NdDCnmDX/GQVmoj+FviTT6DTcv8N0HRSdiAJZ5Vas8rQ HpzedUXAxmEUWc6ECPdHCbv8xGBKgk7PrkfPzAVV0wlcEy5ancwvK+c2CBnGjCGHxBg8j2zM8APNM 4/w3SDAsSo77zzo+fUZi3hFAyBXUlT+u98DSvNQLhsfxDtSVfpqGRbbdRqAWkuDZXmAlmKqflHUj0 XVBuHbyQ==; 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 1f6248-0000zz-0F; Tue, 10 Apr 2018 22:48:40 +0000 Received: from mail.bootlin.com ([62.4.15.54]) by bombadil.infradead.org with esmtp (Exim 4.90_1 #2 (Red Hat Linux)) id 1f620j-0006H9-MO for linux-mtd@lists.infradead.org; Tue, 10 Apr 2018 22:45:12 +0000 Received: by mail.bootlin.com (Postfix, from userid 110) id 25AC320893; Wed, 11 Apr 2018 00:44:46 +0200 (CEST) X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on mail.bootlin.com X-Spam-Level: X-Spam-Status: No, score=-1.0 required=5.0 tests=ALL_TRUSTED,SHORTCIRCUIT shortcircuit=ham autolearn=disabled version=3.4.0 Received: from localhost.localdomain (unknown [91.160.177.164]) by mail.bootlin.com (Postfix) with ESMTPSA id B7FCE20728; Wed, 11 Apr 2018 00:44:45 +0200 (CEST) From: Boris Brezillon To: David Woodhouse , Brian Norris , Boris Brezillon , Marek Vasut , Richard Weinberger , Cyrille Pitchen , linux-mtd@lists.infradead.org, Miquel Raynal , Mark Brown , linux-spi@vger.kernel.org Subject: [PATCH v2 05/10] spi: Make support for regular transfers optional when ->mem_ops != NULL Date: Wed, 11 Apr 2018 00:44:34 +0200 Message-Id: <20180410224439.9260-6-boris.brezillon@bootlin.com> X-Mailer: git-send-email 2.14.1 In-Reply-To: <20180410224439.9260-1-boris.brezillon@bootlin.com> References: <20180410224439.9260-1-boris.brezillon@bootlin.com> X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20180410_154510_119948_49A5648E X-CRM114-Status: GOOD ( 21.29 ) X-Spam-Score: -0.0 (/) X-Spam-Report: SpamAssassin version 3.4.1 on bombadil.infradead.org summary: Content analysis details: (-0.0 points) pts rule name description ---- ---------------------- -------------------------------------------------- -0.0 RCVD_IN_DNSWL_NONE RBL: Sender listed at http://www.dnswl.org/, no trust [62.4.15.54 listed in list.dnswl.org] -0.0 SPF_PASS SPF: sender matches SPF record X-BeenThere: linux-mtd@lists.infradead.org X-Mailman-Version: 2.1.21 Precedence: list List-Id: Linux MTD discussion mailing list List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Yogesh Gaur , Vignesh R , Kamal Dasu , Maxime Chevallier , Peter Pan , Frieder Schrempf , =?utf-8?b?UmFmYcWCIE1pxYJlY2tp?= , Sourav Poddar MIME-Version: 1.0 Sender: "linux-mtd" Errors-To: linux-mtd-bounces+incoming=patchwork.ozlabs.org@lists.infradead.org Some SPI/QuadSPI controllers only expose a high-level SPI memory interface, thus preventing any regular SPI transfers from being done. In that case, SPI controller drivers can leave all ->transfer_xxx() hooks empty and only implement the spi_mem_ops interface. Adjust the core to allow such situations: - extend spi_controller_check_ops() to accept situations where all ->transfer_xxx() pointers are NULL only if ->mem_ops != NULL - make sure we do not initialize the SPI message queue if ctlr->transfer_one and ctlr->transfer_one_message are missing - return -ENOTSUPP if someone tries to do a regular SPI transfer on a controller that does not support it Signed-off-by: Boris Brezillon --- drivers/spi/spi.c | 33 ++++++++++++++++++++++++++------- 1 file changed, 26 insertions(+), 7 deletions(-) diff --git a/drivers/spi/spi.c b/drivers/spi/spi.c index d7e046128b3f..4961a5e91941 100644 --- a/drivers/spi/spi.c +++ b/drivers/spi/spi.c @@ -28,6 +28,7 @@ #include #include #include +#include #include #include #include @@ -2069,12 +2070,19 @@ static int of_spi_register_master(struct spi_controller *ctlr) static int spi_controller_check_ops(struct spi_controller *ctlr) { /* - * The controller must at least implement one of the ->transfer() - * hooks. + * The controller may implement only the high-level SPI-memory like + * operations if it does not support regular SPI transfers, and this is + * valid use case. + * If ->mem_ops is NULL, we request that at least one of the + * ->transfer_xxx() method be implemented. */ - if (!ctlr->transfer && !ctlr->transfer_one && - !ctlr->transfer_one_message) + if (ctlr->mem_ops) { + if (!ctlr->mem_ops->exec_op) + return -EINVAL; + } else if (!ctlr->transfer && !ctlr->transfer_one && + !ctlr->transfer_one_message) { return -EINVAL; + } return 0; } @@ -2185,10 +2193,14 @@ int spi_register_controller(struct spi_controller *ctlr) spi_controller_is_slave(ctlr) ? "slave" : "master", dev_name(&ctlr->dev)); - /* If we're using a queued driver, start the queue */ - if (ctlr->transfer) + /* + * If we're using a queued driver, start the queue. Note that we don't + * need the queueing logic if the driver is only supporting high-level + * memory operations. + */ + if (ctlr->transfer) { dev_info(dev, "controller is unqueued, this is deprecated\n"); - else { + } else if (ctlr->transfer_one || ctlr->transfer_one_message) { status = spi_controller_initialize_queue(ctlr); if (status) { device_del(&ctlr->dev); @@ -2918,6 +2930,13 @@ static int __spi_async(struct spi_device *spi, struct spi_message *message) { struct spi_controller *ctlr = spi->controller; + /* + * Some controllers do not support doing regular SPI transfers. Return + * ENOTSUPP when this is the case. + */ + if (!ctlr->transfer) + return -ENOTSUPP; + message->spi = spi; SPI_STATISTICS_INCREMENT_FIELD(&ctlr->statistics, spi_async);