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=-12.8 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH, MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,USER_AGENT_GIT autolearn=unavailable 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 1D1A1C433E3 for ; Mon, 17 Aug 2020 18:29:15 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 0168C2053B for ; Mon, 17 Aug 2020 18:29:15 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1597688955; bh=L6SlWHQmOlG7InphGxh1u2m96mugPu3A3OzyT6FCBJI=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=FeCksCn9NcNlNUH0ikyznzMRCqHp+9HC+gKGr997xCckFySv9NWhPVG11zErBxpYR N9Ltm4b74UbmD5u7usJ1wiVKbM78OoMOI7dBFc6GOoyPpQ30oANdNh/uTvjNwNg/sk i2t2Y65MDxCfm9nyz5suL3qihbfUpvyhUC5ntbwM= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2390956AbgHQS1Q (ORCPT ); Mon, 17 Aug 2020 14:27:16 -0400 Received: from mail.kernel.org ([198.145.29.99]:49544 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2388174AbgHQQCE (ORCPT ); Mon, 17 Aug 2020 12:02:04 -0400 Received: from localhost (83-86-89-107.cable.dynamic.v4.ziggo.nl [83.86.89.107]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 3B211207FF; Mon, 17 Aug 2020 16:02:03 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1597680123; bh=L6SlWHQmOlG7InphGxh1u2m96mugPu3A3OzyT6FCBJI=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=Y68EuzNFUHgzBht8BwzD2BN2Cr7rGFmyyso1yIb/I72k1ScN/2Tjbrdaszqk5xRlz KB297OXARxYVz3AtkZCbF3Od4ip/mnoKag8re8zyTgQ/80URnD8AU6K6Wwz53wgNgp zjKdr5wDJtUXYYMB8fxSvf3cIq/LU98a/WWg2eIM= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Dilip Kota , Mark Brown , Sasha Levin Subject: [PATCH 5.4 031/270] spi: lantiq: fix: Rx overflow error in full duplex mode Date: Mon, 17 Aug 2020 17:13:52 +0200 Message-Id: <20200817143757.346687525@linuxfoundation.org> X-Mailer: git-send-email 2.28.0 In-Reply-To: <20200817143755.807583758@linuxfoundation.org> References: <20200817143755.807583758@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Dilip Kota [ Upstream commit 661ccf2b3f1360be50242726f7c26ced6a9e7d52 ] In full duplex mode, rx overflow error is observed. To overcome the error, wait until the complete data got received and proceed further. Fixes: 17f84b793c01 ("spi: lantiq-ssc: add support for Lantiq SSC SPI controller") Signed-off-by: Dilip Kota Link: https://lore.kernel.org/r/efb650b0faa49a00788c4e0ca8ef7196bdba851d.1594957019.git.eswara.kota@linux.intel.com Signed-off-by: Mark Brown Signed-off-by: Sasha Levin --- drivers/spi/spi-lantiq-ssc.c | 10 ++++++++++ 1 file changed, 10 insertions(+) diff --git a/drivers/spi/spi-lantiq-ssc.c b/drivers/spi/spi-lantiq-ssc.c index 9dfe8b04e6880..55394bdbc5a30 100644 --- a/drivers/spi/spi-lantiq-ssc.c +++ b/drivers/spi/spi-lantiq-ssc.c @@ -184,6 +184,7 @@ struct lantiq_ssc_spi { unsigned int tx_fifo_size; unsigned int rx_fifo_size; unsigned int base_cs; + unsigned int fdx_tx_level; }; static u32 lantiq_ssc_readl(const struct lantiq_ssc_spi *spi, u32 reg) @@ -481,6 +482,7 @@ static void tx_fifo_write(struct lantiq_ssc_spi *spi) u32 data; unsigned int tx_free = tx_fifo_free(spi); + spi->fdx_tx_level = 0; while (spi->tx_todo && tx_free) { switch (spi->bits_per_word) { case 2 ... 8: @@ -509,6 +511,7 @@ static void tx_fifo_write(struct lantiq_ssc_spi *spi) lantiq_ssc_writel(spi, data, LTQ_SPI_TB); tx_free--; + spi->fdx_tx_level++; } } @@ -520,6 +523,13 @@ static void rx_fifo_read_full_duplex(struct lantiq_ssc_spi *spi) u32 data; unsigned int rx_fill = rx_fifo_level(spi); + /* + * Wait until all expected data to be shifted in. + * Otherwise, rx overrun may occur. + */ + while (rx_fill != spi->fdx_tx_level) + rx_fill = rx_fifo_level(spi); + while (rx_fill) { data = lantiq_ssc_readl(spi, LTQ_SPI_RB); -- 2.25.1