From patchwork Thu Sep 19 20:25:01 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Miquel Raynal X-Patchwork-Id: 11153239 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 3DDD814ED for ; Thu, 19 Sep 2019 20:25:12 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 1CE32217D6 for ; Thu, 19 Sep 2019 20:25:12 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2404637AbfISUZL (ORCPT ); Thu, 19 Sep 2019 16:25:11 -0400 Received: from relay8-d.mail.gandi.net ([217.70.183.201]:37451 "EHLO relay8-d.mail.gandi.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2404462AbfISUZL (ORCPT ); Thu, 19 Sep 2019 16:25:11 -0400 X-Originating-IP: 91.224.148.103 Received: from localhost.localdomain (unknown [91.224.148.103]) (Authenticated sender: miquel.raynal@bootlin.com) by relay8-d.mail.gandi.net (Postfix) with ESMTPSA id 9A3091BF204; Thu, 19 Sep 2019 20:25:07 +0000 (UTC) From: Miquel Raynal To: Mark Brown Cc: , , Mason Yang , Julien Su , Thomas Petazzoni , Boris Brezillon , Miquel Raynal , stable@vger.kernel.org Subject: [PATCH 1/4] spi: mxic: Fix transmit path Date: Thu, 19 Sep 2019 22:25:01 +0200 Message-Id: <20190919202504.9619-1-miquel.raynal@bootlin.com> X-Mailer: git-send-email 2.20.1 MIME-Version: 1.0 X-Spam-Flag: yes X-Spam-Level: ************************** X-GND-Spam-Score: 400 X-GND-Status: SPAM Sender: linux-spi-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-spi@vger.kernel.org In certain circumstances, it is needed to check INT_TX_EMPTY and INT_RX_NOT_EMPTY in the transmit path, not only in the receive path. In both cases, the delay penalty is negligible. Fixes: b942d80b0a39 ("spi: Add MXIC controller driver") Cc: stable@vger.kernel.org Suggested-by: Mason Yang Signed-off-by: Miquel Raynal --- 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 f48563c09b97..eaa7a6a9044d 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);