1 files changed, 63 insertions, 0 deletions
diff --git a/target/linux/bcm27xx/patches-6.1/950-1176-ASoC-dwc-Fix-full-duplex-mode.patch b/target/linux/bcm27xx/patches-6.1/950-1176-ASoC-dwc-Fix-full-duplex-mode.patch
new file mode 100644
index 0000000000..f4b7098fae
--- /dev/null
+++ b/target/linux/bcm27xx/patches-6.1/950-1176-ASoC-dwc-Fix-full-duplex-mode.patch
@@ -0,0 +1,63 @@
+From cbc65d9c95088d1437a5a84c7d6628b8d27a86f1 Mon Sep 17 00:00:00 2001
+From: Phil Elwell <phil@raspberrypi.com>
+Date: Tue, 28 Nov 2023 12:14:03 +0000
+Subject: [PATCH] ASoC: dwc: Fix full-duplex mode
+
+Configuration of the DMA register was carelessly zeroing bits that may
+used by a stream in the other direction. Preserve them instead.
+
+See: https://github.com/raspberrypi/linux/issues/5741
+
+Signed-off-by: Phil Elwell <phil@raspberrypi.com>
+---
+ sound/soc/dwc/dwc-i2s.c | 20 +++++++++++++-------
+ 1 file changed, 13 insertions(+), 7 deletions(-)
+
+--- a/sound/soc/dwc/dwc-i2s.c
++++ b/sound/soc/dwc/dwc-i2s.c
+@@ -189,10 +189,17 @@ static void dw_i2s_config(struct dw_i2s_
+ {
+ 	struct i2s_clk_config_data *config = &dev->config;
+ 	u32 ch_reg;
+-	u32 dmacr = 0;
++	u32 dmacr;
+ 
+ 	i2s_disable_channels(dev, stream);
+ 
++	dmacr = i2s_read_reg(dev->i2s_base, DMACR);
++
++	if (stream == SNDRV_PCM_STREAM_PLAYBACK)
++		dmacr &= ~(DMACR_DMAEN_TXCH0 * 0xf);
++	else
++		dmacr &= ~(DMACR_DMAEN_RXCH0 * 0xf);
++
+ 	for (ch_reg = 0; ch_reg < (config->chan_nr / 2); ch_reg++) {
+ 		if (stream == SNDRV_PCM_STREAM_PLAYBACK) {
+ 			i2s_write_reg(dev->i2s_base, TCR(ch_reg),
+@@ -210,10 +217,6 @@ static void dw_i2s_config(struct dw_i2s_
+ 			dmacr |= (DMACR_DMAEN_RXCH0 << ch_reg);
+ 		}
+ 	}
+-	if (stream == SNDRV_PCM_STREAM_PLAYBACK)
+-		dmacr |= DMACR_DMAEN_TX;
+-	else if (stream == SNDRV_PCM_STREAM_CAPTURE)
+-		dmacr |= DMACR_DMAEN_RX;
+ 
+ 	i2s_write_reg(dev->i2s_base, DMACR, dmacr);
+ }
+@@ -319,10 +322,13 @@ static int dw_i2s_startup(struct snd_pcm
+ 
+ 	dw_i2s_config(dev, substream->stream);
+ 	dmacr = i2s_read_reg(dev->i2s_base, DMACR);
+-	if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK)
++	if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK) {
+ 		dma_data = &dev->play_dma_data;
+-	else if (substream->stream == SNDRV_PCM_STREAM_CAPTURE)
++		dmacr |= DMACR_DMAEN_TX;
++	} else if (substream->stream == SNDRV_PCM_STREAM_CAPTURE) {
+ 		dma_data = &dev->capture_dma_data;
++		dmacr |= DMACR_DMAEN_RX;
++	}
+ 
+ 	snd_soc_dai_set_dma_data(cpu_dai, substream, (void *)dma_data);
+ 	i2s_write_reg(dev->i2s_base, DMACR, dmacr);