From mboxrd@z Thu Jan 1 00:00:00 1970 From: Shawn Lin Subject: [PATCH v6 10/10] ASoC: rockchip_i2s: modify DMA max burst to 1 Date: Thu, 15 Oct 2015 09:36:48 +0800 Message-ID: <1444873008-2589-1-git-send-email-shawn.lin@rock-chips.com> References: <1444872865-2169-1-git-send-email-shawn.lin@rock-chips.com> Cc: Lars-Peter Clausen , Doug Anderson , Olof Johansson , Sonny Rao , Addy Ke , Boojin Kim , dmaengine@vger.kernel.org, linux-kernel@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-rockchip@lists.infradead.org, alsa-devel@alsa-project.org, linux-spi@vger.kernel.org, Yiwei Cai , Shawn Lin , Jianqun Xu To: Vinod Koul , Heiko Stuebner , Jaroslav Kysela , Takashi Iwai , Mark Brown Return-path: In-Reply-To: <1444872865-2169-1-git-send-email-shawn.lin@rock-chips.com> Sender: linux-kernel-owner@vger.kernel.org List-Id: linux-spi.vger.kernel.org From: Yiwei Cai Test with command - arecord -D hw:0,0 /tmp/a.wav, there are the error dump: dma-pl330 ffb20000.dma-controller: fill_queue:2251 Bad Desc(7) This error is happening when no a multiple of burst size * burst length are coming in. The root cause is pl330 dma controller on Rockchips' platform cannot support DMAFLUSHP instruction which make dma to flush the req of non-aligned or non-multiple of what we set before. The saftest way is to set dma max burst to 1. Signed-off-by: Yiwei Cai Fixes: 4495c89fc ("ASoC: add driver for Rockchip RK3xxx I2S") Signed-off-by: Shawn Lin cc: Addy Ke cc: Jianqun Xu cc: Heiko Stuebner cc: Olof Johansson cc: Doug Anderson cc: Sonny Rao Acked-by: Mark Brown --- Changes in v6: - remove quirks and get dma caps in order to limit burst Changes in v5: - use switch statement for dma_quirk's manipulation Changes in v4: None Changes in v3: None Changes in v2: None Changes in v1: None sound/soc/rockchip/rockchip_i2s.c | 18 ++++++++++++++++-- 1 file changed, 16 insertions(+), 2 deletions(-) diff --git a/sound/soc/rockchip/rockchip_i2s.c b/sound/soc/rockchip/rockchip_i2s.c index b936102..f00200a 100644 --- a/sound/soc/rockchip/rockchip_i2s.c +++ b/sound/soc/rockchip/rockchip_i2s.c @@ -418,6 +418,7 @@ static int rockchip_i2s_probe(struct platform_device *pdev) struct rk_i2s_dev *i2s; struct resource *res; void __iomem *regs; + struct dma_slave_caps *dma_caps; int ret; i2s = devm_kzalloc(&pdev->dev, sizeof(*i2s), GFP_KERNEL); @@ -459,11 +460,24 @@ static int rockchip_i2s_probe(struct platform_device *pdev) i2s->playback_dma_data.addr = res->start + I2S_TXDR; i2s->playback_dma_data.addr_width = DMA_SLAVE_BUSWIDTH_4_BYTES; - i2s->playback_dma_data.maxburst = 4; i2s->capture_dma_data.addr = res->start + I2S_RXDR; i2s->capture_dma_data.addr_width = DMA_SLAVE_BUSWIDTH_4_BYTES; - i2s->capture_dma_data.maxburst = 4; + + if (snd_dmaengine_pcm_get_caps(&pdev->dev, &dma_caps) == 0) { + if (dma_caps.max_burst > 4) { + i2s->playback_dma_data.maxburst = 4; + i2s->capture_dma_data.maxburst = 4; + } else { + i2s->playback_dma_data.maxburst = 1; + i2s->capture_dma_data.maxburst = 1; + } + } else { + i2s->playback_dma_data.maxburst = 1; + i2s->capture_dma_data.maxburst = 1; + dev_info(&pdev->dev, + "Can't get dma caps, default limit maxburst to 1.\n"); + } i2s->dev = &pdev->dev; dev_set_drvdata(&pdev->dev, i2s); -- 2.3.7