From patchwork Thu Dec 3 07:53:28 2015 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Koro Chen X-Patchwork-Id: 7756831 Return-Path: X-Original-To: patchwork-alsa-devel@patchwork.kernel.org Delivered-To: patchwork-parsemail@patchwork1.web.kernel.org Received: from mail.kernel.org (mail.kernel.org [198.145.29.136]) by patchwork1.web.kernel.org (Postfix) with ESMTP id 09F9D9F350 for ; Thu, 3 Dec 2015 07:54:49 +0000 (UTC) Received: from mail.kernel.org (localhost [127.0.0.1]) by mail.kernel.org (Postfix) with ESMTP id 1D6692049D for ; Thu, 3 Dec 2015 07:54:48 +0000 (UTC) Received: from alsa0.perex.cz (alsa0.perex.cz [77.48.224.243]) by mail.kernel.org (Postfix) with ESMTP id 7D88A20451 for ; Thu, 3 Dec 2015 07:54:46 +0000 (UTC) Received: by alsa0.perex.cz (Postfix, from userid 1000) id C8253266670; Thu, 3 Dec 2015 08:54:44 +0100 (CET) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on mail.kernel.org X-Spam-Status: No, score=-2.6 required=5.0 tests=BAYES_00,NO_DNS_FOR_FROM, RCVD_IN_DNSWL_LOW, UNPARSEABLE_RELAY autolearn=unavailable version=3.3.1 Received: from alsa0.perex.cz (localhost [127.0.0.1]) by alsa0.perex.cz (Postfix) with ESMTP id 76A3A2652C1; Thu, 3 Dec 2015 08:54:37 +0100 (CET) X-Original-To: alsa-devel@alsa-project.org Delivered-To: alsa-devel@alsa-project.org Received: by alsa0.perex.cz (Postfix, from userid 1000) id E842826650D; Thu, 3 Dec 2015 08:54:35 +0100 (CET) Received: from mailgw01.mediatek.com (unknown [210.61.82.183]) by alsa0.perex.cz (Postfix) with ESMTP id 23AE5265294 for ; Thu, 3 Dec 2015 08:54:27 +0100 (CET) X-Listener-Flag: 11101 Received: from mtkhts07.mediatek.inc [(172.21.101.69)] by mailgw01.mediatek.com (envelope-from ) (mhqrelay.mediatek.com ESMTP with TLS) with ESMTP id 439669153; Thu, 03 Dec 2015 15:54:25 +0800 Received: from mtkslt301 (10.21.14.114) by mtkhts07.mediatek.inc (172.21.101.73) with Microsoft SMTP Server id 14.3.181.6; Thu, 3 Dec 2015 15:54:22 +0800 Received: by mtkslt301 (Postfix, from userid 11333) id E57FC183AC6; Thu, 3 Dec 2015 15:54:22 +0800 (CST) From: Koro Chen To: , Date: Thu, 3 Dec 2015 15:53:28 +0800 Message-ID: <1449129208-63615-1-git-send-email-koro.chen@mediatek.com> X-Mailer: git-send-email 1.7.9.5 MIME-Version: 1.0 X-MTK: N Cc: alsa-devel@alsa-project.org, srv_heupstream@mediatek.com, s.hauer@pengutronix.de, linux-kernel@vger.kernel.org, Koro Chen , linux-mediatek@lists.infradead.org, linux-arm-kernel@lists.infradead.org Subject: [alsa-devel] [PATCH] ASoC: mediatek: Use current HW pointer for pointer callback X-BeenThere: alsa-devel@alsa-project.org X-Mailman-Version: 2.1.14 Precedence: list List-Id: "Alsa-devel mailing list for ALSA developers - http://www.alsa-project.org" List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: alsa-devel-bounces@alsa-project.org Sender: alsa-devel-bounces@alsa-project.org X-Virus-Scanned: ClamAV using ClamSMTP Previously we recorded "last interrupt position" and used it in pointer callback. This is not correct implementation, and it causes underruns when user space monitors buffer level to decide when to send next data chunk in low latency application. Remove position recording in IRQ handler and also hw_ptr in struct mtk_afe_memif used to record that, and let pointer callback reports current HW pointer instead. Signed-off-by: Koro Chen --- sound/soc/mediatek/mtk-afe-common.h | 1 - sound/soc/mediatek/mtk-afe-pcm.c | 22 +++++++++++----------- 2 files changed, 11 insertions(+), 12 deletions(-) diff --git a/sound/soc/mediatek/mtk-afe-common.h b/sound/soc/mediatek/mtk-afe-common.h index cc4393c..9b1af1a 100644 --- a/sound/soc/mediatek/mtk-afe-common.h +++ b/sound/soc/mediatek/mtk-afe-common.h @@ -92,7 +92,6 @@ struct mtk_afe_memif_data { struct mtk_afe_memif { unsigned int phys_buf_addr; int buffer_size; - unsigned int hw_ptr; /* Previous IRQ's HW ptr */ struct snd_pcm_substream *substream; const struct mtk_afe_memif_data *data; const struct mtk_afe_irq_data *irqdata; diff --git a/sound/soc/mediatek/mtk-afe-pcm.c b/sound/soc/mediatek/mtk-afe-pcm.c index 7f71343..5399a0e 100644 --- a/sound/soc/mediatek/mtk-afe-pcm.c +++ b/sound/soc/mediatek/mtk-afe-pcm.c @@ -175,8 +175,17 @@ static snd_pcm_uframes_t mtk_afe_pcm_pointer struct snd_soc_pcm_runtime *rtd = substream->private_data; struct mtk_afe *afe = snd_soc_platform_get_drvdata(rtd->platform); struct mtk_afe_memif *memif = &afe->memif[rtd->cpu_dai->id]; + unsigned int hw_ptr; + int ret; + + ret = regmap_read(afe->regmap, memif->data->reg_ofs_cur, &hw_ptr); + if (ret || hw_ptr == 0) { + dev_err(afe->dev, "%s hw_ptr err\n", __func__); + hw_ptr = memif->phys_buf_addr; + } - return bytes_to_frames(substream->runtime, memif->hw_ptr); + return bytes_to_frames(substream->runtime, + hw_ptr - memif->phys_buf_addr); } static const struct snd_pcm_ops mtk_afe_pcm_ops = { @@ -602,7 +611,6 @@ static int mtk_afe_dais_hw_params(struct snd_pcm_substream *substream, memif->phys_buf_addr = substream->runtime->dma_addr; memif->buffer_size = substream->runtime->dma_bytes; - memif->hw_ptr = 0; /* start */ regmap_write(afe->regmap, @@ -737,7 +745,6 @@ static int mtk_afe_dais_trigger(struct snd_pcm_substream *substream, int cmd, /* and clear pending IRQ */ regmap_write(afe->regmap, AFE_IRQ_CLR, 1 << memif->data->irq_clr_shift); - memif->hw_ptr = 0; return 0; default: return -EINVAL; @@ -1081,7 +1088,7 @@ static const struct regmap_config mtk_afe_regmap_config = { static irqreturn_t mtk_afe_irq_handler(int irq, void *dev_id) { struct mtk_afe *afe = dev_id; - unsigned int reg_value, hw_ptr; + unsigned int reg_value; int i, ret; ret = regmap_read(afe->regmap, AFE_IRQ_STATUS, ®_value); @@ -1097,13 +1104,6 @@ static irqreturn_t mtk_afe_irq_handler(int irq, void *dev_id) if (!(reg_value & (1 << memif->data->irq_clr_shift))) continue; - ret = regmap_read(afe->regmap, memif->data->reg_ofs_cur, - &hw_ptr); - if (ret || hw_ptr == 0) { - dev_err(afe->dev, "%s hw_ptr err\n", __func__); - hw_ptr = memif->phys_buf_addr; - } - memif->hw_ptr = hw_ptr - memif->phys_buf_addr; snd_pcm_period_elapsed(memif->substream); }