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: 7756841 Return-Path: X-Original-To: patchwork-linux-mediatek@patchwork.kernel.org Delivered-To: patchwork-parsemail@patchwork2.web.kernel.org Received: from mail.kernel.org (mail.kernel.org [198.145.29.136]) by patchwork2.web.kernel.org (Postfix) with ESMTP id 3D76DBEEE1 for ; Thu, 3 Dec 2015 07:55:06 +0000 (UTC) Received: from mail.kernel.org (localhost [127.0.0.1]) by mail.kernel.org (Postfix) with ESMTP id 55B4D20502 for ; Thu, 3 Dec 2015 07:55:05 +0000 (UTC) Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.9]) (using TLSv1.2 with cipher AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 67D13204C9 for ; Thu, 3 Dec 2015 07:55:04 +0000 (UTC) Received: from localhost ([127.0.0.1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.80.1 #2 (Red Hat Linux)) id 1a4OjH-0001so-UY; Thu, 03 Dec 2015 07:55:03 +0000 Received: from [210.61.82.183] (helo=mailgw01.mediatek.com) by bombadil.infradead.org with esmtps (Exim 4.80.1 #2 (Red Hat Linux)) id 1a4Oj7-0001UR-V4; Thu, 03 Dec 2015 07:54:54 +0000 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: , Subject: [PATCH] ASoC: mediatek: Use current HW pointer for pointer callback 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 X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20151202_235454_311683_F55E0BE6 X-CRM114-Status: GOOD ( 17.45 ) X-Spam-Score: -1.1 (-) X-BeenThere: linux-mediatek@lists.infradead.org X-Mailman-Version: 2.1.20 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , 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 Sender: "Linux-mediatek" Errors-To: linux-mediatek-bounces+patchwork-linux-mediatek=patchwork.kernel.org@lists.infradead.org X-Spam-Status: No, score=-4.2 required=5.0 tests=BAYES_00, RCVD_IN_DNSWL_MED, T_RP_MATCHES_RCVD, UNPARSEABLE_RELAY autolearn=unavailable version=3.3.1 X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on mail.kernel.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); }