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=-3.0 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_PASS,URIBL_BLOCKED,USER_AGENT_GIT autolearn=ham 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 94D6CC4321D for ; Fri, 24 Aug 2018 16:05:22 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 56EA220661 for ; Fri, 24 Aug 2018 16:05:22 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 56EA220661 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=lucaceresoli.net Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727355AbeHXTkh (ORCPT ); Fri, 24 Aug 2018 15:40:37 -0400 Received: from srv-hp10-72.netsons.net ([94.141.22.72]:40527 "EHLO srv-hp10-72.netsons.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726504AbeHXTkf (ORCPT ); Fri, 24 Aug 2018 15:40:35 -0400 Received: from [109.168.11.45] (port=57958 helo=pc-ceresoli.dev.aim) by srv-hp10.netsons.net with esmtpa (Exim 4.91) (envelope-from ) id 1ftEaJ-00E38u-CA; Fri, 24 Aug 2018 18:05:15 +0200 From: Luca Ceresoli To: alsa-devel@alsa-project.org Cc: Luca Ceresoli , Liam Girdwood , Mark Brown , Jaroslav Kysela , Takashi Iwai , Lars-Peter Clausen , linux-kernel@vger.kernel.org Subject: [PATCH 1/1] axi-i2s: set period size register Date: Fri, 24 Aug 2018 18:04:30 +0200 Message-Id: <20180824160430.10222-2-luca@lucaceresoli.net> X-Mailer: git-send-email 2.17.1 In-Reply-To: <20180824160430.10222-1-luca@lucaceresoli.net> References: <20180824160430.10222-1-luca@lucaceresoli.net> X-AntiAbuse: This header was added to track abuse, please include it with any abuse report X-AntiAbuse: Primary Hostname - srv-hp10.netsons.net X-AntiAbuse: Original Domain - vger.kernel.org X-AntiAbuse: Originator/Caller UID/GID - [47 12] / [47 12] X-AntiAbuse: Sender Address Domain - lucaceresoli.net X-Get-Message-Sender-Via: srv-hp10.netsons.net: authenticated_id: luca+lucaceresoli.net/only user confirmed/virtual account not confirmed X-Authenticated-Sender: srv-hp10.netsons.net: luca@lucaceresoli.net X-Source: X-Source-Args: X-Source-Dir: Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org The default value of the PERIOD_LEN register is 0 and results in axi-i2s keeping TLAST always asserted in its AXI Stream output. When the AXI Stream is sent to a Xilinx AXI-DMA, this results in the DMA generating an interrupt flood and ALSA produce a corrupted recording. This is because AXI-DMA raises an interrupt whenever TLAST is active. Fix by setting the PERIOD_LEN register as soon as the period is known. This way TLAST is emitted once per period, and the DMA raises interrupts correctly. Signed-off-by: Luca Ceresoli --- sound/soc/adi/axi-i2s.c | 15 ++++++++++++++- 1 file changed, 14 insertions(+), 1 deletion(-) diff --git a/sound/soc/adi/axi-i2s.c b/sound/soc/adi/axi-i2s.c index 4c23381727a1..af581a313a40 100644 --- a/sound/soc/adi/axi-i2s.c +++ b/sound/soc/adi/axi-i2s.c @@ -24,6 +24,7 @@ #define AXI_I2S_REG_CTRL 0x04 #define AXI_I2S_REG_CLK_CTRL 0x08 #define AXI_I2S_REG_STATUS 0x10 +#define AXI_I2S_REG_PERIOD_LEN 0x18 #define AXI_I2S_REG_RX_FIFO 0x28 #define AXI_I2S_REG_TX_FIFO 0x2C @@ -101,6 +102,17 @@ static int axi_i2s_hw_params(struct snd_pcm_substream *substream, return 0; } +static int axi_i2s_prepare(struct snd_pcm_substream *substream, + struct snd_soc_dai *dai) +{ + struct axi_i2s *i2s = snd_soc_dai_get_drvdata(dai); + unsigned int period_bytes = snd_pcm_lib_period_bytes(substream); + + /* adi_i2s counts 32-bit words, thus divide bytes by 4 */ + return regmap_write(i2s->regmap, AXI_I2S_REG_PERIOD_LEN, + (period_bytes / 4) - 1); +} + static int axi_i2s_startup(struct snd_pcm_substream *substream, struct snd_soc_dai *dai) { @@ -147,6 +159,7 @@ static const struct snd_soc_dai_ops axi_i2s_dai_ops = { .shutdown = axi_i2s_shutdown, .trigger = axi_i2s_trigger, .hw_params = axi_i2s_hw_params, + .prepare = axi_i2s_prepare, }; static struct snd_soc_dai_driver axi_i2s_dai = { @@ -175,7 +188,7 @@ static const struct regmap_config axi_i2s_regmap_config = { .reg_bits = 32, .reg_stride = 4, .val_bits = 32, - .max_register = AXI_I2S_REG_STATUS, + .max_register = AXI_I2S_REG_PERIOD_LEN, }; static int axi_i2s_probe(struct platform_device *pdev) -- 2.17.1