[PATCH v3 7/9] ASoC: qcom: Add QAIF IRQ handling, suspend/resume and platform register

[Harendra Gautam <harendra.gautam@oss.qualcomm.com>]

Register the ASoC component, request the QAIF interrupt and add trigger
handling to enable or disable DMA and its interrupt sources. Dispatch the
top-level IRQ status to the AIF and CIF DMA handlers, report period elapsed
events to ALSA, warn on xrun conditions and stop the stream on bus errors.

Signed-off-by: Harendra Gautam <harendra.gautam@oss.qualcomm.com>
---
 sound/soc/qcom/qaif-platform.c | 391 +++++++++++++++++++++++++++++++++
 1 file changed, 391 insertions(+)

diff --git a/sound/soc/qcom/qaif-platform.c b/sound/soc/qcom/qaif-platform.c
index 4b4647641d11..2e5dc5b081cd 100644
--- a/sound/soc/qcom/qaif-platform.c
+++ b/sound/soc/qcom/qaif-platform.c
@@ -542,3 +542,394 @@ static int qaif_platform_copy(struct snd_soc_component *component,
 
 	return (copied != bytes) ? -EFAULT : 0;
 }
+
+static int qaif_platform_irq_op(struct qaif_drv_data *drvdata, int dir,
+				enum qaif_irq_type irq_type, int idx,
+				enum qaif_irq_op op)
+{
+	const struct qaif_variant *v = drvdata->variant;
+	struct regmap *map = drvdata->audio_qaif_map;
+	unsigned int bit = BIT(idx);
+	unsigned int val = op == QAIF_IRQ_ENABLE ? bit : 0;
+	u32 per_reg, err_reg, xrun_reg;
+	int ret;
+
+	if (dir == SNDRV_PCM_STREAM_PLAYBACK) {
+		per_reg = op == QAIF_IRQ_CLEAR ? QAIF_EE_RDDMA_PERIOD_IRQ_CLR_REG(v, irq_type)
+					       : QAIF_EE_RDDMA_PERIOD_IRQ_EN_REG(v, irq_type);
+		xrun_reg = op == QAIF_IRQ_CLEAR ? QAIF_EE_RDDMA_UF_IRQ_CLR_REG(v, irq_type)
+						: QAIF_EE_RDDMA_UF_IRQ_EN_REG(v, irq_type);
+		err_reg = op == QAIF_IRQ_CLEAR ? QAIF_EE_RDDMA_ERR_RSP_IRQ_CLR_REG(v, irq_type)
+					       : QAIF_EE_RDDMA_ERR_RSP_IRQ_EN_REG(v, irq_type);
+	} else {
+		per_reg = op == QAIF_IRQ_CLEAR ? QAIF_EE_WRDMA_PERIOD_IRQ_CLR_REG(v, irq_type)
+					       : QAIF_EE_WRDMA_PERIOD_IRQ_EN_REG(v, irq_type);
+		xrun_reg = op == QAIF_IRQ_CLEAR ? QAIF_EE_WRDMA_OF_IRQ_CLR_REG(v, irq_type)
+						: QAIF_EE_WRDMA_OF_IRQ_EN_REG(v, irq_type);
+		err_reg = op == QAIF_IRQ_CLEAR ? QAIF_EE_WRDMA_ERR_RSP_IRQ_CLR_REG(v, irq_type)
+					       : QAIF_EE_WRDMA_ERR_RSP_IRQ_EN_REG(v, irq_type);
+	}
+
+	if (op == QAIF_IRQ_CLEAR) {
+		ret = regmap_write(map, per_reg, bit);
+		if (ret)
+			return ret;
+		ret = regmap_write(map, xrun_reg, bit);
+		if (ret)
+			return ret;
+		return regmap_write(map, err_reg, bit);
+	}
+
+	ret = regmap_write_bits(map, per_reg, bit, val);
+	if (ret)
+		return ret;
+	ret = regmap_write_bits(map, xrun_reg, bit, val);
+	if (ret)
+		return ret;
+	return regmap_write_bits(map, err_reg, bit, val);
+}
+
+static int qaif_platform_pcmops_trigger(struct snd_soc_component *component,
+					struct snd_pcm_substream *substream,
+					int cmd)
+{
+	struct snd_soc_pcm_runtime *soc_runtime = snd_soc_substream_to_rtd(substream);
+	struct snd_soc_dai *cpu_dai = snd_soc_rtd_to_cpu(soc_runtime, 0);
+	struct qaif_drv_data *drvdata = snd_soc_component_get_drvdata(component);
+	const struct qaif_variant *v = drvdata->variant;
+	struct qaif_pcm_data *data = substream->runtime->private_data;
+	unsigned int dai_id = cpu_dai->driver->id;
+	enum qaif_irq_type irq_type = qaif_is_cif_dma_port(dai_id) ? QAIF_CIF_IRQ : QAIF_AIF_IRQ;
+	struct regmap *map = drvdata->audio_qaif_map;
+	int idx = data->dma_reg_idx;
+	int ret;
+
+	switch (cmd) {
+	case SNDRV_PCM_TRIGGER_START:
+	case SNDRV_PCM_TRIGGER_RESUME:
+	case SNDRV_PCM_TRIGGER_PAUSE_RELEASE:
+		ret = qaif_platform_irq_op(drvdata, substream->stream, irq_type,
+					   idx, QAIF_IRQ_CLEAR);
+		if (ret) {
+			dev_err(soc_runtime->dev, "error clearing irq regs: %d\n", ret);
+			return ret;
+		}
+		ret = regmap_update_bits(map,
+					 qaif_dmacfg_reg(v, idx, substream->stream, dai_id),
+					 QAIF_DMACFG_DYNCLK_BIT, QAIF_DMACFG_DYNCLK_BIT);
+		if (ret) {
+			dev_err(soc_runtime->dev, "error enabling dma_dynclk: %d\n", ret);
+			return ret;
+		}
+		ret = regmap_update_bits(map,
+					 qaif_dmactl_reg(v, idx, substream->stream, dai_id),
+					 QAIF_DMACTL_ENABLE_BIT, QAIF_DMACTL_ENABLE_BIT);
+		if (ret) {
+			dev_err(soc_runtime->dev, "error enabling DMA: %d\n", ret);
+			return ret;
+		}
+		ret = qaif_platform_irq_op(drvdata, substream->stream, irq_type,
+					   idx, QAIF_IRQ_ENABLE);
+		if (ret)
+			dev_err(soc_runtime->dev, "error enabling irq regs: %d\n", ret);
+		break;
+	case SNDRV_PCM_TRIGGER_STOP:
+	case SNDRV_PCM_TRIGGER_SUSPEND:
+	case SNDRV_PCM_TRIGGER_PAUSE_PUSH:
+		ret = regmap_update_bits(map,
+					 qaif_dmactl_reg(v, idx, substream->stream, dai_id),
+					 QAIF_DMACTL_ENABLE_BIT, 0);
+		if (ret) {
+			dev_err(soc_runtime->dev, "error disabling DMA: %d\n", ret);
+			return ret;
+		}
+		ret = regmap_update_bits(map,
+					 qaif_dmacfg_reg(v, idx, substream->stream, dai_id),
+					 QAIF_DMACFG_DYNCLK_BIT, 0);
+		if (ret)
+			dev_err(soc_runtime->dev, "error disabling dma_dynclk: %d\n", ret);
+		ret = qaif_platform_irq_op(drvdata, substream->stream, irq_type,
+					   idx, QAIF_IRQ_DISABLE);
+		if (ret)
+			dev_err(soc_runtime->dev, "error disabling irq regs: %d\n", ret);
+		break;
+	default:
+		return -EINVAL;
+	}
+	return ret;
+}
+
+static int qaif_platform_pcmops_sync_stop(struct snd_soc_component *component,
+					  struct snd_pcm_substream *substream)
+{
+	struct snd_soc_pcm_runtime *soc_runtime = snd_soc_substream_to_rtd(substream);
+	struct snd_soc_dai *cpu_dai = snd_soc_rtd_to_cpu(soc_runtime, 0);
+	struct qaif_drv_data *drvdata = snd_soc_component_get_drvdata(component);
+	struct qaif_pcm_data *data = substream->runtime->private_data;
+	unsigned int dai_id = cpu_dai->driver->id;
+	enum qaif_irq_type irq_type = qaif_is_cif_dma_port(dai_id) ? QAIF_CIF_IRQ : QAIF_AIF_IRQ;
+	int idx = data->dma_reg_idx;
+	int ret;
+
+	synchronize_irq(drvdata->audio_qaif_irq);
+	ret = qaif_platform_irq_op(drvdata, substream->stream, irq_type,
+				   idx, QAIF_IRQ_CLEAR);
+	if (ret)
+		dev_err(soc_runtime->dev, "error clearing irq regs: %d\n", ret);
+	return ret;
+}
+
+static irqreturn_t qaif_process_dma_irq(struct qaif_drv_data *drvdata,
+					u32 stat_reg_addr,
+					u32 clr_reg_addr,
+					enum qaif_irq_type irq_type,
+					enum qaif_dma_dir dma_type,
+					enum qaif_irq irq,
+					struct snd_pcm_substream **substream)
+{
+	const struct qaif_variant *v = drvdata->variant;
+	unsigned int reg = 0;
+	int dma_idx, stream_dma_idx, rv, num_dma, stream_offset, array_size;
+	u32 mask;
+	struct snd_pcm_substream *ss;
+
+	stream_offset = (dma_type == QAIF_DMA_WRDMA) ?
+		((irq_type == QAIF_AIF_IRQ) ? v->wrdma_start : v->codec_wrdma_start) : 0;
+	num_dma = (dma_type == QAIF_DMA_WRDMA) ?
+		((irq_type == QAIF_AIF_IRQ) ? v->num_wrdma : v->num_codec_wrdma) :
+		((irq_type == QAIF_AIF_IRQ) ? v->num_rddma : v->num_codec_rddma);
+	if (!num_dma)
+		return IRQ_NONE;
+
+	array_size = (irq_type == QAIF_AIF_IRQ) ?
+		QAIF_MAX_AIF_DMA_IDX : QAIF_MAX_CIF_DMA_IDX;
+	if (stream_offset + num_dma > array_size) {
+		dev_err(regmap_get_device(drvdata->audio_qaif_map),
+			"DMA index range %d+%d exceeds substream table %d\n",
+			stream_offset, num_dma, array_size);
+		return IRQ_NONE;
+	}
+	mask = GENMASK(num_dma - 1, 0);
+
+	rv = regmap_read(drvdata->audio_qaif_map, stat_reg_addr, &reg);
+	if (rv) {
+		dev_err_ratelimited(regmap_get_device(drvdata->audio_qaif_map),
+				    "error reading stat reg 0x%x: %d\n", stat_reg_addr, rv);
+		return IRQ_NONE;
+	}
+
+	if (!(reg & mask)) {
+		dev_warn_ratelimited(regmap_get_device(drvdata->audio_qaif_map),
+				     "spurious IRQ: stat reg 0x%x status 0x%x mask 0x%x\n",
+				     stat_reg_addr, reg, mask);
+		return IRQ_NONE;
+	}
+
+	if (regmap_write(drvdata->audio_qaif_map, clr_reg_addr, reg & mask))
+		return IRQ_NONE;
+
+	for (dma_idx = 0; dma_idx < num_dma; dma_idx++) {
+		stream_dma_idx = dma_idx + stream_offset;
+		ss = READ_ONCE(substream[stream_dma_idx]);
+		if (!(reg & BIT(dma_idx)) || !ss)
+			continue;
+		switch (irq) {
+		case QAIF_IRQ_PERIOD:
+			snd_pcm_period_elapsed(ss);
+			break;
+		case QAIF_IRQ_OVERFLOW:
+		case QAIF_IRQ_UNDERFLOW:
+			dev_warn_ratelimited(regmap_get_device(drvdata->audio_qaif_map),
+					     "QAIF DMA xRun\n");
+			snd_pcm_stop_xrun(ss);
+			break;
+		case QAIF_IRQ_ERROR:
+			snd_pcm_stop_xrun(ss);
+			dev_err_ratelimited(regmap_get_device(drvdata->audio_qaif_map),
+					    "QAIF bus error\n");
+			break;
+		}
+	}
+	return IRQ_HANDLED;
+}
+
+static irqreturn_t qaif_aif_irq_handler(struct qaif_drv_data *drvdata, u32 status)
+{
+	const struct qaif_variant *v = drvdata->variant;
+	struct snd_pcm_substream **ss = drvdata->aif_substream;
+	irqreturn_t ret = IRQ_NONE;
+
+	if (status & QAIF_SUMMARY_BITMASK_AIF_PERIOD_RDDMA)
+		ret |= qaif_process_dma_irq(drvdata,
+					    QAIF_EE_RDDMA_PERIOD_IRQ_STAT_REG(v, QAIF_AIF_IRQ),
+					    QAIF_EE_RDDMA_PERIOD_IRQ_CLR_REG(v, QAIF_AIF_IRQ),
+					    QAIF_AIF_IRQ, QAIF_DMA_RDDMA, QAIF_IRQ_PERIOD, ss);
+	if (status & QAIF_SUMMARY_BITMASK_AIF_PERIOD_WRDMA)
+		ret |= qaif_process_dma_irq(drvdata,
+					    QAIF_EE_WRDMA_PERIOD_IRQ_STAT_REG(v, QAIF_AIF_IRQ),
+					    QAIF_EE_WRDMA_PERIOD_IRQ_CLR_REG(v, QAIF_AIF_IRQ),
+					    QAIF_AIF_IRQ, QAIF_DMA_WRDMA, QAIF_IRQ_PERIOD, ss);
+	if (status & QAIF_SUMMARY_BITMASK_AIF_OVERFLOW_WRDMA)
+		ret |= qaif_process_dma_irq(drvdata,
+					    QAIF_EE_WRDMA_OF_IRQ_STAT_REG(v, QAIF_AIF_IRQ),
+					    QAIF_EE_WRDMA_OF_IRQ_CLR_REG(v, QAIF_AIF_IRQ),
+					    QAIF_AIF_IRQ, QAIF_DMA_WRDMA, QAIF_IRQ_OVERFLOW, ss);
+	if (status & QAIF_SUMMARY_BITMASK_AIF_UNDERFLOW_RDDMA)
+		ret |= qaif_process_dma_irq(drvdata,
+					    QAIF_EE_RDDMA_UF_IRQ_STAT_REG(v, QAIF_AIF_IRQ),
+					    QAIF_EE_RDDMA_UF_IRQ_CLR_REG(v, QAIF_AIF_IRQ),
+					    QAIF_AIF_IRQ, QAIF_DMA_RDDMA, QAIF_IRQ_UNDERFLOW, ss);
+	if (status & QAIF_SUMMARY_BITMASK_AIF_ERR_RSP_RDDMA)
+		ret |= qaif_process_dma_irq(drvdata,
+					    QAIF_EE_RDDMA_ERR_RSP_IRQ_STAT_REG(v, QAIF_AIF_IRQ),
+					    QAIF_EE_RDDMA_ERR_RSP_IRQ_CLR_REG(v, QAIF_AIF_IRQ),
+					    QAIF_AIF_IRQ, QAIF_DMA_RDDMA, QAIF_IRQ_ERROR, ss);
+	if (status & QAIF_SUMMARY_BITMASK_AIF_ERR_RSP_WRDMA)
+		ret |= qaif_process_dma_irq(drvdata,
+					    QAIF_EE_WRDMA_ERR_RSP_IRQ_STAT_REG(v, QAIF_AIF_IRQ),
+					    QAIF_EE_WRDMA_ERR_RSP_IRQ_CLR_REG(v, QAIF_AIF_IRQ),
+					    QAIF_AIF_IRQ, QAIF_DMA_WRDMA, QAIF_IRQ_ERROR, ss);
+	return ret;
+}
+
+static irqreturn_t qaif_cif_irq_handler(struct qaif_drv_data *drvdata, u32 status)
+{
+	const struct qaif_variant *v = drvdata->variant;
+	struct snd_pcm_substream **ss = drvdata->cif_substream;
+	irqreturn_t ret = IRQ_NONE;
+
+	if (status & QAIF_SUMMARY_BITMASK_CIF_PERIOD_RDDMA)
+		ret |= qaif_process_dma_irq(drvdata,
+					    QAIF_EE_RDDMA_PERIOD_IRQ_STAT_REG(v, QAIF_CIF_IRQ),
+					    QAIF_EE_RDDMA_PERIOD_IRQ_CLR_REG(v, QAIF_CIF_IRQ),
+					    QAIF_CIF_IRQ, QAIF_DMA_RDDMA, QAIF_IRQ_PERIOD, ss);
+	if (status & QAIF_SUMMARY_BITMASK_CIF_PERIOD_WRDMA)
+		ret |= qaif_process_dma_irq(drvdata,
+					    QAIF_EE_WRDMA_PERIOD_IRQ_STAT_REG(v, QAIF_CIF_IRQ),
+					    QAIF_EE_WRDMA_PERIOD_IRQ_CLR_REG(v, QAIF_CIF_IRQ),
+					    QAIF_CIF_IRQ, QAIF_DMA_WRDMA, QAIF_IRQ_PERIOD, ss);
+	if (status & QAIF_SUMMARY_BITMASK_CIF_OVERFLOW_WRDMA)
+		ret |= qaif_process_dma_irq(drvdata,
+					    QAIF_EE_WRDMA_OF_IRQ_STAT_REG(v, QAIF_CIF_IRQ),
+					    QAIF_EE_WRDMA_OF_IRQ_CLR_REG(v, QAIF_CIF_IRQ),
+					    QAIF_CIF_IRQ, QAIF_DMA_WRDMA, QAIF_IRQ_OVERFLOW, ss);
+	if (status & QAIF_SUMMARY_BITMASK_CIF_UNDERFLOW_RDDMA)
+		ret |= qaif_process_dma_irq(drvdata,
+					    QAIF_EE_RDDMA_UF_IRQ_STAT_REG(v, QAIF_CIF_IRQ),
+					    QAIF_EE_RDDMA_UF_IRQ_CLR_REG(v, QAIF_CIF_IRQ),
+					    QAIF_CIF_IRQ, QAIF_DMA_RDDMA, QAIF_IRQ_UNDERFLOW, ss);
+	if (status & QAIF_SUMMARY_BITMASK_CIF_ERR_RSP_RDDMA)
+		ret |= qaif_process_dma_irq(drvdata,
+					    QAIF_EE_RDDMA_ERR_RSP_IRQ_STAT_REG(v, QAIF_CIF_IRQ),
+					    QAIF_EE_RDDMA_ERR_RSP_IRQ_CLR_REG(v, QAIF_CIF_IRQ),
+					    QAIF_CIF_IRQ, QAIF_DMA_RDDMA, QAIF_IRQ_ERROR, ss);
+	if (status & QAIF_SUMMARY_BITMASK_CIF_ERR_RSP_WRDMA)
+		ret |= qaif_process_dma_irq(drvdata,
+					    QAIF_EE_WRDMA_ERR_RSP_IRQ_STAT_REG(v, QAIF_CIF_IRQ),
+					    QAIF_EE_WRDMA_ERR_RSP_IRQ_CLR_REG(v, QAIF_CIF_IRQ),
+					    QAIF_CIF_IRQ, QAIF_DMA_WRDMA, QAIF_IRQ_ERROR, ss);
+	return ret;
+}
+
+static const struct qaif_irq_map qaif_irq_clients[] = {
+	{ QAIF_CLIENT_ID_AIF_DMA, QAIF_BITMASK_AIF_RDDMA_WRDMA, qaif_aif_irq_handler },
+	{ QAIF_CLIENT_ID_CIF_DMA, QAIF_BITMASK_CIF_RDDMA_WRDMA, qaif_cif_irq_handler },
+};
+
+static irqreturn_t asoc_platform_qaif_irq(int irq, void *data)
+{
+	struct qaif_drv_data *drvdata = data;
+	const struct qaif_variant *v = drvdata->variant;
+	u32 summary_irq_status;
+	int rv, client;
+	irqreturn_t ret = IRQ_NONE;
+
+	rv = regmap_read(drvdata->audio_qaif_map, QAIF_SUMMARY_IRQSTAT_REG(v),
+			 &summary_irq_status);
+	if (rv) {
+		dev_err(regmap_get_device(drvdata->audio_qaif_map),
+			"error reading from irqstat reg: %d\n", rv);
+		return IRQ_NONE;
+	}
+
+	if (!(summary_irq_status & QAIF_ALL_CLIENTS_MASK))
+		return IRQ_NONE;
+
+	for (client = 0; client < ARRAY_SIZE(qaif_irq_clients); client++) {
+		if (summary_irq_status & qaif_irq_clients[client].mask)
+			ret |= qaif_irq_clients[client].client_irq_handler(drvdata,
+									   summary_irq_status);
+	}
+	return ret;
+}
+
+static const struct snd_soc_component_driver qaif_component_driver = {
+	.name		= DRV_NAME,
+	.open		= qaif_platform_pcmops_open,
+	.close		= qaif_platform_pcmops_close,
+	.hw_params	= qaif_platform_pcmops_hw_params,
+	.hw_free	= qaif_platform_pcmops_hw_free,
+	.prepare	= qaif_platform_pcmops_prepare,
+	.trigger	= qaif_platform_pcmops_trigger,
+	.sync_stop	= qaif_platform_pcmops_sync_stop,
+	.pointer	= qaif_platform_pcmops_pointer,
+	.mmap		= qaif_platform_pcmops_mmap,
+	.copy		= qaif_platform_copy,
+};
+
+int asoc_qcom_qaif_platform_register(struct platform_device *pdev)
+{
+	struct qaif_drv_data *drvdata = platform_get_drvdata(pdev);
+	struct of_phandle_args iommu_spec;
+	u32 sid;
+	int ret;
+
+	if (!drvdata || !drvdata->variant)
+		return dev_err_probe(&pdev->dev, -EINVAL,
+				     "Invalid drvdata or variant\n");
+
+	ret = of_parse_phandle_with_fixed_args(pdev->dev.of_node,
+					       "iommus", 2, 0,
+					       &iommu_spec);
+	if (ret)
+		return dev_err_probe(&pdev->dev, ret,
+				     "failed to parse iommus property\n");
+	sid = iommu_spec.args[0];
+	of_node_put(iommu_spec.np);
+	drvdata->smmu_csid_bits = sid & QAIF_CSID_MASK;
+
+	/*
+	 * The DMA base register only holds the low 32 bits of the buffer
+	 * address, so the coherent buffer must come from the low 32-bit
+	 * address space.
+	 */
+	ret = dma_set_mask_and_coherent(&pdev->dev, DMA_BIT_MASK(32));
+	if (ret)
+		return dev_err_probe(&pdev->dev, ret,
+				     "Failed to set 32-bit DMA mask\n");
+
+	drvdata->audio_qaif_irq = platform_get_irq(pdev, 0);
+	if (drvdata->audio_qaif_irq < 0)
+		return dev_err_probe(&pdev->dev, drvdata->audio_qaif_irq,
+				     "Failed to get IRQ\n");
+
+	drvdata->qaif_hw_configured = false;
+	mutex_init(&drvdata->stream_lock);
+
+	ret = devm_request_irq(&pdev->dev, drvdata->audio_qaif_irq,
+			       asoc_platform_qaif_irq, 0,
+			       "qaif-irq-audio-core", drvdata);
+	if (ret)
+		return dev_err_probe(&pdev->dev, ret, "irq request failed\n");
+
+	ret = devm_snd_soc_register_component(&pdev->dev, &qaif_component_driver, NULL, 0);
+	if (ret)
+		return dev_err_probe(&pdev->dev, ret,
+				     "Failed to register platform component\n");
+	return 0;
+}
+EXPORT_SYMBOL_GPL(asoc_qcom_qaif_platform_register);
+
+MODULE_DESCRIPTION("Qualcomm Audio Interface (QAIF) PCM platform driver");
+MODULE_AUTHOR("Harendra Gautam <harendra.gautam@oss.qualcomm.com>");
+MODULE_LICENSE("GPL");
-- 
2.34.1