ASoC: Intel: avs: Probe compress operations

Add compress operations handlers for data extraction through probes. A
single HDAudio stream is enlisted for said purpose. Operations follow
same protocol as for standard PCM streaming on HOST side.

Signed-off-by: Cezary Rojewski <[e-mail]>
Link: https://lore.kernel.org/r/[e-mail]
Signed-off-by: Mark Brown <[e-mail]>

sound/soc/intel/Kconfig

···
 	select SND_SOC_ACPI if ACPI
 	select SND_SOC_TOPOLOGY
 	select SND_SOC_HDA
+	select SND_SOC_COMPRESS if DEBUG_FS
 	select SND_HDA_EXT_CORE
 	select SND_HDA_DSP_LOADER
 	select SND_INTEL_DSP_CONFIG

sound/soc/intel/avs/avs.h

···
 	u32 aging_timer_period;
 	u32 fifo_full_timer_period;
 	u32 logged_resources;	/* context dependent: core or library */
+	/* probes */
+	struct hdac_ext_stream *extractor;
+	unsigned int num_probe_streams;
 #endif
 };
 

sound/soc/intel/avs/probes.c

···
 //          Amadeusz Slawinski <[e-mail]>
 //
 
+#include <sound/compress_driver.h>
+#include <sound/hdaudio_ext.h>
+#include <sound/hdaudio.h>
+#include <sound/soc.h>
 #include "avs.h"
 #include "messages.h"
 
-__maybe_unused
 static int avs_dsp_init_probe(struct avs_dev *adev, union avs_connector_node_id node_id,
 			      size_t buffer_size)
-
 {
 	struct avs_probe_cfg cfg = {{0}};
 	struct avs_module_entry mentry;
···
 				   sizeof(cfg), &dummy);
 }
 
-__maybe_unused
 static void avs_dsp_delete_probe(struct avs_dev *adev)
 {
 	struct avs_module_entry mentry;
···
 	/* There is only ever one probe module instance. */
 	avs_dsp_delete_module(adev, mentry.module_id, 0, INVALID_PIPELINE_ID, 0);
 }
+
+static inline struct hdac_ext_stream *avs_compr_get_host_stream(struct snd_compr_stream *cstream)
+{
+	return cstream->runtime->private_data;
+}
+
+static int avs_probe_compr_open(struct snd_compr_stream *cstream, struct snd_soc_dai *dai)
+{
+	struct avs_dev *adev = to_avs_dev(dai->dev);
+	struct hdac_bus *bus = &adev->base.core;
+	struct hdac_ext_stream *host_stream;
+
+	if (adev->extractor) {
+		dev_err(dai->dev, "Cannot open more than one extractor stream\n");
+		return -EEXIST;
+	}
+
+	host_stream = snd_hdac_ext_cstream_assign(bus, cstream);
+	if (!host_stream) {
+		dev_err(dai->dev, "Failed to assign HDAudio stream for extraction\n");
+		return -EBUSY;
+	}
+
+	adev->extractor = host_stream;
+	hdac_stream(host_stream)->curr_pos = 0;
+	cstream->runtime->private_data = host_stream;
+
+	return 0;
+}
+
+static int avs_probe_compr_free(struct snd_compr_stream *cstream, struct snd_soc_dai *dai)
+{
+	struct hdac_ext_stream *host_stream = avs_compr_get_host_stream(cstream);
+	struct avs_dev *adev = to_avs_dev(dai->dev);
+	struct avs_probe_point_desc *desc;
+	/* Extractor node identifier. */
+	unsigned int vindex = INVALID_NODE_ID.vindex;
+	size_t num_desc;
+	int i, ret;
+
+	/* Disconnect all probe points. */
+	ret = avs_ipc_probe_get_points(adev, &desc, &num_desc);
+	if (ret) {
+		dev_err(dai->dev, "get probe points failed: %d\n", ret);
+		ret = AVS_IPC_RET(ret);
+		goto exit;
+	}
+
+	for (i = 0; i < num_desc; i++)
+		if (desc[i].node_id.vindex == vindex)
+			avs_ipc_probe_disconnect_points(adev, &desc[i].id, 1);
+	kfree(desc);
+
+exit:
+	if (adev->num_probe_streams) {
+		adev->num_probe_streams--;
+		if (!adev->num_probe_streams) {
+			avs_dsp_delete_probe(adev);
+			avs_dsp_enable_d0ix(adev);
+		}
+	}
+
+	snd_hdac_stream_cleanup(hdac_stream(host_stream));
+	hdac_stream(host_stream)->prepared = 0;
+	snd_hdac_ext_stream_release(host_stream, HDAC_EXT_STREAM_TYPE_HOST);
+
+	snd_compr_free_pages(cstream);
+	adev->extractor = NULL;
+
+	return ret;
+}
+
+static int avs_probe_compr_set_params(struct snd_compr_stream *cstream,
+				      struct snd_compr_params *params, struct snd_soc_dai *dai)
+{
+	struct hdac_ext_stream *host_stream = avs_compr_get_host_stream(cstream);
+	struct snd_compr_runtime *rtd = cstream->runtime;
+	struct avs_dev *adev = to_avs_dev(dai->dev);
+	/* compr params do not store bit depth, default to S32_LE. */
+	snd_pcm_format_t format = SNDRV_PCM_FORMAT_S32_LE;
+	unsigned int format_val;
+	int bps, ret;
+
+	hdac_stream(host_stream)->bufsize = 0;
+	hdac_stream(host_stream)->period_bytes = 0;
+	hdac_stream(host_stream)->format_val = 0;
+	cstream->dma_buffer.dev.type = SNDRV_DMA_TYPE_DEV_SG;
+	cstream->dma_buffer.dev.dev = adev->dev;
+
+	ret = snd_compr_malloc_pages(cstream, rtd->buffer_size);
+	if (ret < 0)
+		return ret;
+	bps = snd_pcm_format_physical_width(format);
+	if (bps < 0)
+		return bps;
+	format_val = snd_hdac_calc_stream_format(params->codec.sample_rate, params->codec.ch_out,
+						 format, bps, 0);
+	ret = snd_hdac_stream_set_params(hdac_stream(host_stream), format_val);
+	if (ret < 0)
+		return ret;
+	ret = snd_hdac_stream_setup(hdac_stream(host_stream));
+	if (ret < 0)
+		return ret;
+
+	hdac_stream(host_stream)->prepared = 1;
+
+	if (!adev->num_probe_streams) {
+		union avs_connector_node_id node_id;
+
+		/* D0ix not allowed during probing. */
+		ret = avs_dsp_disable_d0ix(adev);
+		if (ret)
+			return ret;
+
+		node_id.vindex = hdac_stream(host_stream)->stream_tag - 1;
+		node_id.dma_type = AVS_DMA_HDA_HOST_INPUT;
+
+		ret = avs_dsp_init_probe(adev, node_id, rtd->dma_bytes);
+		if (ret < 0) {
+			dev_err(dai->dev, "probe init failed: %d\n", ret);
+			avs_dsp_enable_d0ix(adev);
+			return ret;
+		}
+	}
+
+	adev->num_probe_streams++;
+	return 0;
+}
+
+static int avs_probe_compr_trigger(struct snd_compr_stream *cstream, int cmd,
+				   struct snd_soc_dai *dai)
+{
+	struct hdac_ext_stream *host_stream = avs_compr_get_host_stream(cstream);
+	struct avs_dev *adev = to_avs_dev(dai->dev);
+	struct hdac_bus *bus = &adev->base.core;
+	unsigned long cookie;
+
+	if (!hdac_stream(host_stream)->prepared)
+		return -EPIPE;
+
+	switch (cmd) {
+	case SNDRV_PCM_TRIGGER_START:
+	case SNDRV_PCM_TRIGGER_PAUSE_RELEASE:
+	case SNDRV_PCM_TRIGGER_RESUME:
+		spin_lock_irqsave(&bus->reg_lock, cookie);
+		snd_hdac_stream_start(hdac_stream(host_stream), true);
+		spin_unlock_irqrestore(&bus->reg_lock, cookie);
+		break;
+
+	case SNDRV_PCM_TRIGGER_PAUSE_PUSH:
+	case SNDRV_PCM_TRIGGER_SUSPEND:
+	case SNDRV_PCM_TRIGGER_STOP:
+		spin_lock_irqsave(&bus->reg_lock, cookie);
+		snd_hdac_stream_stop(hdac_stream(host_stream));
+		spin_unlock_irqrestore(&bus->reg_lock, cookie);
+		break;
+
+	default:
+		return -EINVAL;
+	}
+
+	return 0;
+}
+
+static int avs_probe_compr_pointer(struct snd_compr_stream *cstream,
+				   struct snd_compr_tstamp *tstamp, struct snd_soc_dai *dai)
+{
+	struct hdac_ext_stream *host_stream = avs_compr_get_host_stream(cstream);
+	struct snd_soc_pcm_stream *pstream;
+
+	pstream = &dai->driver->capture;
+	tstamp->copied_total = hdac_stream(host_stream)->curr_pos;
+	tstamp->sampling_rate = snd_pcm_rate_bit_to_rate(pstream->rates);
+
+	return 0;
+}
+
+static int avs_probe_compr_copy(struct snd_soc_component *comp, struct snd_compr_stream *cstream,
+				char __user *buf, size_t count)
+{
+	struct snd_compr_runtime *rtd = cstream->runtime;
+	unsigned int offset, n;
+	void *ptr;
+	int ret;
+
+	if (count > rtd->buffer_size)
+		count = rtd->buffer_size;
+
+	div_u64_rem(rtd->total_bytes_transferred, rtd->buffer_size, &offset);
+	ptr = rtd->dma_area + offset;
+	n = rtd->buffer_size - offset;
+
+	if (count < n) {
+		ret = copy_to_user(buf, ptr, count);
+	} else {
+		ret = copy_to_user(buf, ptr, n);
+		ret += copy_to_user(buf + n, rtd->dma_area, count - n);
+	}
+
+	if (ret)
+		return count - ret;
+	return count;
+}
+
+__maybe_unused
+static const struct snd_soc_cdai_ops avs_probe_dai_ops = {
+	.startup = avs_probe_compr_open,
+	.shutdown = avs_probe_compr_free,
+	.set_params = avs_probe_compr_set_params,
+	.trigger = avs_probe_compr_trigger,
+	.pointer = avs_probe_compr_pointer,
+};
+
+__maybe_unused
+static const struct snd_compress_ops avs_probe_compress_ops = {
+	.copy = avs_probe_compr_copy,
+};