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git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
kernel
os
linux
ASoC: dwc: add DMA handshake control
DMA mode uses hardware handshake signals. DMACR register is used to enable
the DMA Controller interface operation. So add DMA enable/disable to
i2s_start()/i2s_stop() functions if using DMA mode.
Signed-off-by: Maxim Kochetkov <fido_max@inbox.ru>
Link: https://lore.kernel.org/r/20230613191910.725049-1-fido_max@inbox.ru
Signed-off-by: Mark Brown <broonie@kernel.org>
authored by
Maxim Kochetkov
and committed by
Mark Brown
a42e988b
02474880
+43
-2
+37
-2
sound/soc/dwc/dwc-i2s.c
+37
-2
sound/soc/dwc/dwc-i2s.c
···
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return IRQ_NONE;
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}
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+
static void i2s_enable_dma(struct dw_i2s_dev *dev, u32 stream)
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{
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u32 dma_reg = i2s_read_reg(dev->i2s_base, I2S_DMACR);
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+
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/* Enable DMA handshake for stream */
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if (stream == SNDRV_PCM_STREAM_PLAYBACK)
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dma_reg |= I2S_DMAEN_TXBLOCK;
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else
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dma_reg |= I2S_DMAEN_RXBLOCK;
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+
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i2s_write_reg(dev->i2s_base, I2S_DMACR, dma_reg);
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}
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+
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static void i2s_disable_dma(struct dw_i2s_dev *dev, u32 stream)
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{
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u32 dma_reg = i2s_read_reg(dev->i2s_base, I2S_DMACR);
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+
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/* Disable DMA handshake for stream */
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if (stream == SNDRV_PCM_STREAM_PLAYBACK) {
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dma_reg &= ~I2S_DMAEN_TXBLOCK;
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i2s_write_reg(dev->i2s_base, I2S_RTXDMA, 1);
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} else {
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dma_reg &= ~I2S_DMAEN_RXBLOCK;
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i2s_write_reg(dev->i2s_base, I2S_RRXDMA, 1);
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}
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i2s_write_reg(dev->i2s_base, I2S_DMACR, dma_reg);
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}
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+
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static void i2s_start(struct dw_i2s_dev *dev,
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struct snd_pcm_substream *substream)
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{
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struct i2s_clk_config_data *config = &dev->config;
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i2s_write_reg(dev->i2s_base, IER, 1);
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-
i2s_enable_irqs(dev, substream->stream, config->chan_nr);
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if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK)
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i2s_write_reg(dev->i2s_base, ITER, 1);
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else
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i2s_write_reg(dev->i2s_base, IRER, 1);
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+
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if (dev->use_pio)
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i2s_enable_irqs(dev, substream->stream, config->chan_nr);
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else
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i2s_enable_dma(dev, substream->stream);
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i2s_write_reg(dev->i2s_base, CER, 1);
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}
···
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else
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i2s_write_reg(dev->i2s_base, IRER, 0);
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-
i2s_disable_irqs(dev, substream->stream, 8);
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if (dev->use_pio)
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i2s_disable_irqs(dev, substream->stream, 8);
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else
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i2s_disable_dma(dev, substream->stream);
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if (!dev->active) {
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i2s_write_reg(dev->i2s_base, CER, 0);
+6
sound/soc/dwc/local.h
+6
sound/soc/dwc/local.h
···
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#define I2S_COMP_VERSION 0x01F8
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#define I2S_COMP_TYPE 0x01FC
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+
#define I2S_RRXDMA 0x01C4
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#define I2S_RTXDMA 0x01CC
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#define I2S_DMACR 0x0200
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#define I2S_DMAEN_RXBLOCK (1 << 16)
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#define I2S_DMAEN_TXBLOCK (1 << 17)
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/*
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* Component parameter register fields - define the I2S block's
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* configuration.