ASoC: amd: ps: add support for SoundWire DMA interrupts

Move to request_threaded_irq and use thread for handling
SoundWire DMA interrupts.
Whenever audio data equal to the SoundWire FIFO watermark level
are produced/consumed, interrupt is generated.
Acknowledge the interrupt and wake up the irq thread.

Signed-off-by: Vijendar Mukunda <Vijendar.Mukunda@amd.com>
Link: https://lore.kernel.org/r/20230612095903.2113464-6-Vijendar.Mukunda@amd.com
Signed-off-by: Mark Brown <broonie@kernel.org>

sound/soc/amd/ps/acp63.h

@@ -165,6 +165,20 @@ enum acp_config {
 	ACP_CONFIG_15,
 };
 
+enum amd_sdw0_channel {
+	ACP_SDW0_AUDIO0_TX = 0,
+	ACP_SDW0_AUDIO1_TX,
+	ACP_SDW0_AUDIO2_TX,
+	ACP_SDW0_AUDIO0_RX,
+	ACP_SDW0_AUDIO1_RX,
+	ACP_SDW0_AUDIO2_RX,
+};
+
+enum amd_sdw1_channel {
+	ACP_SDW1_AUDIO1_TX,
+	ACP_SDW1_AUDIO1_RX,
+};
+
 struct pdm_stream_instance {
 	u16 num_pages;
 	u16 channels;
@@ -229,6 +243,8 @@ struct sdw_dma_ring_buf_reg {
  * @sdw0_dev_index: SoundWire Manager-0 platform device index
  * @sdw1_dev_index: SoundWire Manager-1 platform device index
  * @sdw_dma_dev_index: SoundWire DMA controller platform device index
+ * @sdw0-dma_intr_stat: DMA interrupt status array for SoundWire manager-SW0 instance
+ * @sdw_dma_intr_stat: DMA interrupt status array for SoundWire manager-SW1 instance
  * @acp_reset: flag set to true when bus reset is applied across all
  * the active SoundWire manager instances
  */
@@ -246,6 +262,8 @@ struct acp63_dev_data {
 	u16 sdw0_dev_index;
 	u16 sdw1_dev_index;
 	u16 sdw_dma_dev_index;
+	u16 sdw0_dma_intr_stat[ACP63_SDW0_DMA_MAX_STREAMS];
+	u16 sdw1_dma_intr_stat[ACP63_SDW1_DMA_MAX_STREAMS];
 	bool acp_reset;
 };
 

sound/soc/amd/ps/pci-ps.c

@@ -99,14 +99,44 @@ static int acp63_deinit(void __iomem *acp_base, struct device *dev)
 	return 0;
 }
 
+static irqreturn_t acp63_irq_thread(int irq, void *context)
+{
+	struct sdw_dma_dev_data *sdw_dma_data;
+	struct acp63_dev_data *adata = context;
+	u32 stream_index;
+	u16 pdev_index;
+
+	pdev_index = adata->sdw_dma_dev_index;
+	sdw_dma_data = dev_get_drvdata(&adata->pdev[pdev_index]->dev);
+
+	for (stream_index = 0; stream_index < ACP63_SDW0_DMA_MAX_STREAMS; stream_index++) {
+		if (adata->sdw0_dma_intr_stat[stream_index]) {
+			if (sdw_dma_data->sdw0_dma_stream[stream_index])
+				snd_pcm_period_elapsed(sdw_dma_data->sdw0_dma_stream[stream_index]);
+			adata->sdw0_dma_intr_stat[stream_index] = 0;
+		}
+	}
+	for (stream_index = 0; stream_index < ACP63_SDW1_DMA_MAX_STREAMS; stream_index++) {
+		if (adata->sdw1_dma_intr_stat[stream_index]) {
+			if (sdw_dma_data->sdw1_dma_stream[stream_index])
+				snd_pcm_period_elapsed(sdw_dma_data->sdw1_dma_stream[stream_index]);
+			adata->sdw1_dma_intr_stat[stream_index] = 0;
+		}
+	}
+	return IRQ_HANDLED;
+}
+
 static irqreturn_t acp63_irq_handler(int irq, void *dev_id)
 {
 	struct acp63_dev_data *adata;
 	struct pdm_dev_data *ps_pdm_data;
 	struct amd_sdw_manager *amd_manager;
 	u32 ext_intr_stat, ext_intr_stat1;
+	u32 stream_id = 0;
 	u16 irq_flag = 0;
+	u16 sdw_dma_irq_flag = 0;
 	u16 pdev_index;
+	u16 index;
 
 	adata = dev_id;
 	if (!adata)
@@ -153,6 +183,54 @@ static irqreturn_t acp63_irq_handler(int irq, void *dev_id)
 			snd_pcm_period_elapsed(ps_pdm_data->capture_stream);
 		irq_flag = 1;
 	}
+	if (ext_intr_stat & ACP_SDW_DMA_IRQ_MASK) {
+		for (index = ACP_AUDIO2_RX_THRESHOLD; index <= ACP_AUDIO0_TX_THRESHOLD; index++) {
+			if (ext_intr_stat & BIT(index)) {
+				writel(BIT(index), adata->acp63_base + ACP_EXTERNAL_INTR_STAT);
+				switch (index) {
+				case ACP_AUDIO0_TX_THRESHOLD:
+					stream_id = ACP_SDW0_AUDIO0_TX;
+					break;
+				case ACP_AUDIO1_TX_THRESHOLD:
+					stream_id = ACP_SDW0_AUDIO1_TX;
+					break;
+				case ACP_AUDIO2_TX_THRESHOLD:
+					stream_id = ACP_SDW0_AUDIO2_TX;
+					break;
+				case ACP_AUDIO0_RX_THRESHOLD:
+					stream_id = ACP_SDW0_AUDIO0_RX;
+					break;
+				case ACP_AUDIO1_RX_THRESHOLD:
+					stream_id = ACP_SDW0_AUDIO1_RX;
+					break;
+				case ACP_AUDIO2_RX_THRESHOLD:
+					stream_id = ACP_SDW0_AUDIO2_RX;
+					break;
+				}
+
+				adata->sdw0_dma_intr_stat[stream_id] = 1;
+				sdw_dma_irq_flag = 1;
+			}
+		}
+	}
+
+	if (ext_intr_stat1 & ACP_P1_AUDIO1_RX_THRESHOLD) {
+		writel(ACP_P1_AUDIO1_RX_THRESHOLD,
+		       adata->acp63_base + ACP_EXTERNAL_INTR_STAT1);
+		adata->sdw1_dma_intr_stat[ACP_SDW1_AUDIO1_RX] = 1;
+		sdw_dma_irq_flag = 1;
+	}
+
+	if (ext_intr_stat1 & ACP_P1_AUDIO1_TX_THRESHOLD) {
+		writel(ACP_P1_AUDIO1_TX_THRESHOLD,
+		       adata->acp63_base + ACP_EXTERNAL_INTR_STAT1);
+		adata->sdw1_dma_intr_stat[ACP_SDW1_AUDIO1_TX] = 1;
+		sdw_dma_irq_flag = 1;
+	}
+
+	if (sdw_dma_irq_flag)
+		return IRQ_WAKE_THREAD;
+
 	if (irq_flag)
 		return IRQ_HANDLED;
 	else
@@ -553,8 +631,8 @@ static int snd_acp63_probe(struct pci_dev *pci,
 	ret = acp63_init(adata->acp63_base, &pci->dev);
 	if (ret)
 		goto release_regions;
-	ret = devm_request_irq(&pci->dev, pci->irq, acp63_irq_handler,
+	ret = devm_request_threaded_irq(&pci->dev, pci->irq, acp63_irq_handler,
-			       irqflags, "ACP_PCI_IRQ", adata);
+					acp63_irq_thread, irqflags, "ACP_PCI_IRQ", adata);
 	if (ret) {
 		dev_err(&pci->dev, "ACP PCI IRQ request failed\n");
 		goto de_init;