From patchwork Thu Nov 3 07:55:46 2016 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Chen-Yu Tsai X-Patchwork-Id: 9410527 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork.web.codeaurora.org (Postfix) with ESMTP id 4BC4860573 for ; Thu, 3 Nov 2016 07:58:57 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 3C9AB2A61D for ; Thu, 3 Nov 2016 07:58:57 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 2EE232A89E; Thu, 3 Nov 2016 07:58:57 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-1.9 required=2.0 tests=BAYES_00, RCVD_IN_DNSWL_NONE autolearn=ham version=3.3.1 Received: from alsa0.perex.cz (alsa0.perex.cz [77.48.224.243]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 34F932A61D for ; Thu, 3 Nov 2016 07:58:55 +0000 (UTC) Received: by alsa0.perex.cz (Postfix, from userid 1000) id 6450D2670FA; Thu, 3 Nov 2016 08:58:54 +0100 (CET) Received: from alsa0.perex.cz (localhost [127.0.0.1]) by alsa0.perex.cz (Postfix) with ESMTP id 379422666D3; Thu, 3 Nov 2016 08:56:29 +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 732C2267112; Thu, 3 Nov 2016 08:56:20 +0100 (CET) Received: from wens.csie.org (mirror2.csie.ntu.edu.tw [140.112.30.76]) by alsa0.perex.cz (Postfix) with ESMTP id BC9472670F9 for ; Thu, 3 Nov 2016 08:56:14 +0100 (CET) Received: by wens.csie.org (Postfix, from userid 1000) id D3B0F5F9FE; Thu, 3 Nov 2016 15:56:10 +0800 (CST) From: Chen-Yu Tsai To: Liam Girdwood , Mark Brown , Jaroslav Kysela , Takashi Iwai , Maxime Ripard , Rob Herring , Mark Rutland Date: Thu, 3 Nov 2016 15:55:46 +0800 Message-Id: <20161103075556.29018-5-wens@csie.org> X-Mailer: git-send-email 2.10.2 In-Reply-To: <20161103075556.29018-1-wens@csie.org> References: <20161103075556.29018-1-wens@csie.org> Cc: devicetree@vger.kernel.org, alsa-devel@alsa-project.org, Vinod Koul , linux-sunxi@googlegroups.com, linux-kernel@vger.kernel.org, Chen-Yu Tsai , linux-arm-kernel@lists.infradead.org Subject: [alsa-devel] [PATCH v2 04/14] ASoC: sun4i-codec: Increase DMA max burst to 8 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: , MIME-Version: 1.0 Errors-To: alsa-devel-bounces@alsa-project.org Sender: alsa-devel-bounces@alsa-project.org X-Virus-Scanned: ClamAV using ClamSMTP According to the DMA engine API documentation, maxburst denotes the largest possible size of a single transfer, so as not to overflow destination FIFOs as explained in this excerpt from dmaengine.h * @src_maxburst: the maximum number of words (note: words, as in * units of the src_addr_width member, not bytes) that can be sent * in one burst to the device. Typically something like half the * FIFO depth on I/O peripherals so you don't overflow it. This * may or may not be applicable on memory sources. * @dst_maxburst: same as src_maxburst but for destination target * mutatis mutandis. The TX FIFO is 64 samples deep for stereo, and the RX FIFO is 16 samples deep. So maxburst could be 32 and 8 for TX and RX respectively. Unfortunately the sunxi DMA controller driver takes maxburst as the requested burst size, rather than a limit, and returns an error for unsupported values. The original value was 4, but some later SoCs do not officially support this burst size. This patch increases maxburst on the TX side to 8, which is supported by all variants of the sunxi DMA controller. Cc: Vinod Koul Signed-off-by: Chen-Yu Tsai Acked-by: Maxime Ripard --- sound/soc/sunxi/sun4i-codec.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/sound/soc/sunxi/sun4i-codec.c b/sound/soc/sunxi/sun4i-codec.c index 61ae502a5061..d867b96d367b 100644 --- a/sound/soc/sunxi/sun4i-codec.c +++ b/sound/soc/sunxi/sun4i-codec.c @@ -886,12 +886,12 @@ static int sun4i_codec_probe(struct platform_device *pdev) /* DMA configuration for TX FIFO */ scodec->playback_dma_data.addr = res->start + quirks->reg_dac_txdata; - scodec->playback_dma_data.maxburst = 4; + scodec->playback_dma_data.maxburst = 8; scodec->playback_dma_data.addr_width = DMA_SLAVE_BUSWIDTH_2_BYTES; /* DMA configuration for RX FIFO */ scodec->capture_dma_data.addr = res->start + quirks->reg_adc_rxdata; - scodec->capture_dma_data.maxburst = 4; + scodec->capture_dma_data.maxburst = 8; scodec->capture_dma_data.addr_width = DMA_SLAVE_BUSWIDTH_2_BYTES; ret = snd_soc_register_codec(&pdev->dev, quirks->codec,