From patchwork Fri Oct 8 16:22:26 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Miquel Raynal X-Patchwork-Id: 12545713 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id D4BA5C433FE for ; Fri, 8 Oct 2021 16:22:55 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id C07D761042 for ; Fri, 8 Oct 2021 16:22:55 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S233985AbhJHQYt (ORCPT ); Fri, 8 Oct 2021 12:24:49 -0400 Received: from relay10.mail.gandi.net ([217.70.178.230]:41503 "EHLO relay10.mail.gandi.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S233947AbhJHQYr (ORCPT ); Fri, 8 Oct 2021 12:24:47 -0400 Received: (Authenticated sender: miquel.raynal@bootlin.com) by relay10.mail.gandi.net (Postfix) with ESMTPSA id 9D2C5240006; Fri, 8 Oct 2021 16:22:48 +0000 (UTC) From: Miquel Raynal To: Richard Weinberger , Vignesh Raghavendra , Tudor Ambarus , Cc: Rob Herring , Mark Brown , Xiangsheng Hou , Boris Brezillon , devicetree@vger.kernel.org, linux-spi@vger.kernel.org, linux-kernel@vger.kernel.org, jaimeliao@mxic.com.tw, juliensu@mxic.com.tw, Thomas Petazzoni , Miquel Raynal , stable@vger.kernel.org, Mason Yang Subject: [RFC PATCH 08/10] spi: mxic: Fix the transmit path Date: Fri, 8 Oct 2021 18:22:26 +0200 Message-Id: <20211008162228.1753083-9-miquel.raynal@bootlin.com> X-Mailer: git-send-email 2.27.0 In-Reply-To: <20211008162228.1753083-1-miquel.raynal@bootlin.com> References: <20211008162228.1753083-1-miquel.raynal@bootlin.com> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-spi@vger.kernel.org By working with external hardware ECC engines, we figured out that Under certain circumstances, it is needed for the SPI controller to check INT_TX_EMPTY and INT_RX_NOT_EMPTY in both receive and transmit path (not only in the receive path). The delay penalty being negligible, move this code in the common path. Fixes: b942d80b0a39 ("spi: Add MXIC controller driver") Cc: stable@vger.kernel.org Suggested-by: Mason Yang Signed-off-by: Miquel Raynal Reviewed-by: Zhengxun Li --- drivers/spi/spi-mxic.c | 28 ++++++++++++---------------- 1 file changed, 12 insertions(+), 16 deletions(-) diff --git a/drivers/spi/spi-mxic.c b/drivers/spi/spi-mxic.c index 96b418293bf2..4fb19e6f94b0 100644 --- a/drivers/spi/spi-mxic.c +++ b/drivers/spi/spi-mxic.c @@ -304,25 +304,21 @@ static int mxic_spi_data_xfer(struct mxic_spi *mxic, const void *txbuf, writel(data, mxic->regs + TXD(nbytes % 4)); + ret = readl_poll_timeout(mxic->regs + INT_STS, sts, + sts & INT_TX_EMPTY, 0, USEC_PER_SEC); + if (ret) + return ret; + + ret = readl_poll_timeout(mxic->regs + INT_STS, sts, + sts & INT_RX_NOT_EMPTY, 0, + USEC_PER_SEC); + if (ret) + return ret; + + data = readl(mxic->regs + RXD); if (rxbuf) { - ret = readl_poll_timeout(mxic->regs + INT_STS, sts, - sts & INT_TX_EMPTY, 0, - USEC_PER_SEC); - if (ret) - return ret; - - ret = readl_poll_timeout(mxic->regs + INT_STS, sts, - sts & INT_RX_NOT_EMPTY, 0, - USEC_PER_SEC); - if (ret) - return ret; - - data = readl(mxic->regs + RXD); data >>= (8 * (4 - nbytes)); memcpy(rxbuf + pos, &data, nbytes); - WARN_ON(readl(mxic->regs + INT_STS) & INT_RX_NOT_EMPTY); - } else { - readl(mxic->regs + RXD); } WARN_ON(readl(mxic->regs + INT_STS) & INT_RX_NOT_EMPTY);