[alsa-devel] Applied "ASoC: rsnd: dma: set bus width to data width for monaural data" to the asoc tree

[Mark Brown]

The patch

   ASoC: rsnd: dma: set bus width to data width for monaural data

has been applied to the asoc tree at

   https://git.kernel.org/pub/scm/linux/kernel/git/broonie/sound.git for-5.5

All being well this means that it will be integrated into the linux-next
tree (usually sometime in the next 24 hours) and sent to Linus during
the next merge window (or sooner if it is a bug fix), however if
problems are discovered then the patch may be dropped or reverted.  

You may get further e-mails resulting from automated or manual testing
and review of the tree, please engage with people reporting problems and
send followup patches addressing any issues that are reported if needed.

If any updates are required or you are submitting further changes they
should be sent as incremental updates against current git, existing
patches will not be replaced.

Please add any relevant lists and maintainers to the CCs when replying
to this mail.

Thanks,
Mark

>From d4d9360bf702890b5d3b1b62d8619a2690dd3278 Mon Sep 17 00:00:00 2001
From: Jiada Wang <jiada_wang at mentor.com>
Date: Tue, 22 Oct 2019 20:55:18 +0200
Subject: [PATCH] ASoC: rsnd: dma: set bus width to data width for monaural
 data

According to R-Car3 HW manual 40.3.3 (Data Format on Audio Local Bus),
in case of monaural data writing or reading through Audio-DMAC,
it's always in Left Justified format, so both src and dst
DMA Bus width should be equal to physical data width.

Therefore set src and dst's DMA bus width to:
 - [monaural case] data width
 - [non-monaural case] 32bits (as prior applying the patch)

Cc: Andrew Gabbasov <andrew_gabbasov at mentor.com>
Cc: Timo Wischer <twischer at de.adit-jv.com>
Signed-off-by: Jiada Wang <jiada_wang at mentor.com>
Signed-off-by: Eugeniu Rosca <erosca at de.adit-jv.com>
Link: https://lore.kernel.org/r/20191022185518.12838-1-erosca@de.adit-jv.com
Signed-off-by: Mark Brown <broonie at kernel.org>
---
 sound/soc/sh/rcar/dma.c | 30 ++++++++++++++++++++++++++++--
 1 file changed, 28 insertions(+), 2 deletions(-)

diff --git a/sound/soc/sh/rcar/dma.c b/sound/soc/sh/rcar/dma.c
index 0324a5c39619..bcb6d5960661 100644
--- a/sound/soc/sh/rcar/dma.c
+++ b/sound/soc/sh/rcar/dma.c
@@ -165,14 +165,40 @@ static int rsnd_dmaen_start(struct rsnd_mod *mod,
 	struct device *dev = rsnd_priv_to_dev(priv);
 	struct dma_async_tx_descriptor *desc;
 	struct dma_slave_config cfg = {};
+	enum dma_slave_buswidth buswidth = DMA_SLAVE_BUSWIDTH_4_BYTES;
 	int is_play = rsnd_io_is_play(io);
 	int ret;
 
+	/*
+	 * in case of monaural data writing or reading through Audio-DMAC
+	 * data is always in Left Justified format, so both src and dst
+	 * DMA Bus width need to be set equal to physical data width.
+	 */
+	if (rsnd_runtime_channel_original(io) == 1) {
+		struct snd_pcm_runtime *runtime = rsnd_io_to_runtime(io);
+		int bits = snd_pcm_format_physical_width(runtime->format);
+
+		switch (bits) {
+		case 8:
+			buswidth = DMA_SLAVE_BUSWIDTH_1_BYTE;
+			break;
+		case 16:
+			buswidth = DMA_SLAVE_BUSWIDTH_2_BYTES;
+			break;
+		case 32:
+			buswidth = DMA_SLAVE_BUSWIDTH_4_BYTES;
+			break;
+		default:
+			dev_err(dev, "invalid format width %d\n", bits);
+			return -EINVAL;
+		}
+	}
+
 	cfg.direction	= is_play ? DMA_MEM_TO_DEV : DMA_DEV_TO_MEM;
 	cfg.src_addr	= dma->src_addr;
 	cfg.dst_addr	= dma->dst_addr;
-	cfg.src_addr_width = DMA_SLAVE_BUSWIDTH_4_BYTES;
-	cfg.dst_addr_width = DMA_SLAVE_BUSWIDTH_4_BYTES;
+	cfg.src_addr_width = buswidth;
+	cfg.dst_addr_width = buswidth;
 
 	dev_dbg(dev, "%s %pad -> %pad\n",
 		rsnd_mod_name(mod),
-- 
2.20.1