From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 92D9B1D523 for ; Wed, 4 Oct 2023 18:06:35 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; dmarc=fail (p=none dis=none) header.from=linuxfoundation.org Authentication-Results: smtp.subspace.kernel.org; spf=fail smtp.mailfrom=linuxfoundation.org Received: by smtp.kernel.org (Postfix) with ESMTPSA id 15690C433C7; Wed, 4 Oct 2023 18:06:34 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1696442795; bh=nV1y//w6qdTzrXuYcGwsKqG0sOOfIUT0j/D4ul+cPSE=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=lFZyIVZLuaRsSOQj0pADpe1UHrI8L+C4EZunEAqbdXEzgyvyYaLtksmLhXEXYdCXb KSX7SZCvwNe74n37u6SDfMRx5RA+jitB1Drf/cFpj+wyXSoFplPzUdFahiVTMowjdo UN4ggLx751Ey+UeaIM1ihJjFmt6nyleLq/09ZYTM= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Tobias Schramm , Mark Brown , Sasha Levin Subject: [PATCH 5.15 111/183] spi: sun6i: reduce DMA RX transfer width to single byte Date: Wed, 4 Oct 2023 19:55:42 +0200 Message-ID: <20231004175208.563117515@linuxfoundation.org> X-Mailer: git-send-email 2.42.0 In-Reply-To: <20231004175203.943277832@linuxfoundation.org> References: <20231004175203.943277832@linuxfoundation.org> User-Agent: quilt/0.67 X-stable: review X-Patchwork-Hint: ignore Precedence: bulk X-Mailing-List: patches@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit 5.15-stable review patch. If anyone has any objections, please let me know. ------------------ From: Tobias Schramm [ Upstream commit 171f8a49f212e87a8b04087568e1b3d132e36a18 ] Through empirical testing it has been determined that sometimes RX SPI transfers with DMA enabled return corrupted data. This is down to single or even multiple bytes lost during DMA transfer from SPI peripheral to memory. It seems the RX FIFO within the SPI peripheral can become confused when performing bus read accesses wider than a single byte to it during an active SPI transfer. This patch reduces the width of individual DMA read accesses to the RX FIFO to a single byte to mitigate that issue. Signed-off-by: Tobias Schramm Link: https://lore.kernel.org/r/20230827152558.5368-2-t.schramm@manjaro.org Signed-off-by: Mark Brown Signed-off-by: Sasha Levin --- drivers/spi/spi-sun6i.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/spi/spi-sun6i.c b/drivers/spi/spi-sun6i.c index 23ad052528dbe..2bfe87873edb3 100644 --- a/drivers/spi/spi-sun6i.c +++ b/drivers/spi/spi-sun6i.c @@ -200,7 +200,7 @@ static int sun6i_spi_prepare_dma(struct sun6i_spi *sspi, struct dma_slave_config rxconf = { .direction = DMA_DEV_TO_MEM, .src_addr = sspi->dma_addr_rx, - .src_addr_width = DMA_SLAVE_BUSWIDTH_4_BYTES, + .src_addr_width = DMA_SLAVE_BUSWIDTH_1_BYTE, .src_maxburst = 8, }; -- 2.40.1