1 files changed, 496 insertions, 0 deletions

diff --git a/sound/soc/soc-generic-dmaengine-pcm.c b/sound/soc/soc-generic-dmaengine-pcm.c
new file mode 100644
index 000000000..9ef80a487
--- /dev/null
+++ b/sound/soc/soc-generic-dmaengine-pcm.c
@@ -0,0 +1,496 @@
+// SPDX-License-Identifier: GPL-2.0+
+//
+//  Copyright (C) 2013, Analog Devices Inc.
+//	Author: Lars-Peter Clausen <lars@metafoo.de>
+
+#include <linux/module.h>
+#include <linux/init.h>
+#include <linux/dmaengine.h>
+#include <linux/slab.h>
+#include <sound/pcm.h>
+#include <sound/pcm_params.h>
+#include <sound/soc.h>
+#include <linux/dma-mapping.h>
+#include <linux/of.h>
+
+#include <sound/dmaengine_pcm.h>
+
+/*
+ * The platforms dmaengine driver does not support reporting the amount of
+ * bytes that are still left to transfer.
+ */
+#define SND_DMAENGINE_PCM_FLAG_NO_RESIDUE BIT(31)
+
+static struct device *dmaengine_dma_dev(struct dmaengine_pcm *pcm,
+	struct snd_pcm_substream *substream)
+{
+	if (!pcm->chan[substream->stream])
+		return NULL;
+
+	return pcm->chan[substream->stream]->device->dev;
+}
+
+/**
+ * snd_dmaengine_pcm_prepare_slave_config() - Generic prepare_slave_config callback
+ * @substream: PCM substream
+ * @params: hw_params
+ * @slave_config: DMA slave config to prepare
+ *
+ * This function can be used as a generic prepare_slave_config callback for
+ * platforms which make use of the snd_dmaengine_dai_dma_data struct for their
+ * DAI DMA data. Internally the function will first call
+ * snd_hwparams_to_dma_slave_config to fill in the slave config based on the
+ * hw_params, followed by snd_dmaengine_set_config_from_dai_data to fill in the
+ * remaining fields based on the DAI DMA data.
+ */
+int snd_dmaengine_pcm_prepare_slave_config(struct snd_pcm_substream *substream,
+	struct snd_pcm_hw_params *params, struct dma_slave_config *slave_config)
+{
+	struct snd_soc_pcm_runtime *rtd = asoc_substream_to_rtd(substream);
+	struct snd_dmaengine_dai_dma_data *dma_data;
+	int ret;
+
+	if (rtd->num_cpus > 1) {
+		dev_err(rtd->dev,
+			"%s doesn't support Multi CPU yet\n", __func__);
+		return -EINVAL;
+	}
+
+	dma_data = snd_soc_dai_get_dma_data(asoc_rtd_to_cpu(rtd, 0), substream);
+
+	ret = snd_hwparams_to_dma_slave_config(substream, params, slave_config);
+	if (ret)
+		return ret;
+
+	snd_dmaengine_pcm_set_config_from_dai_data(substream, dma_data,
+		slave_config);
+
+	return 0;
+}
+EXPORT_SYMBOL_GPL(snd_dmaengine_pcm_prepare_slave_config);
+
+static int dmaengine_pcm_hw_params(struct snd_soc_component *component,
+				   struct snd_pcm_substream *substream,
+				   struct snd_pcm_hw_params *params)
+{
+	struct dmaengine_pcm *pcm = soc_component_to_pcm(component);
+	struct dma_chan *chan = snd_dmaengine_pcm_get_chan(substream);
+	int (*prepare_slave_config)(struct snd_pcm_substream *substream,
+			struct snd_pcm_hw_params *params,
+			struct dma_slave_config *slave_config);
+	struct dma_slave_config slave_config;
+	int ret;
+
+	memset(&slave_config, 0, sizeof(slave_config));
+
+	if (!pcm->config)
+		prepare_slave_config = snd_dmaengine_pcm_prepare_slave_config;
+	else
+		prepare_slave_config = pcm->config->prepare_slave_config;
+
+	if (prepare_slave_config) {
+		ret = prepare_slave_config(substream, params, &slave_config);
+		if (ret)
+			return ret;
+
+		ret = dmaengine_slave_config(chan, &slave_config);
+		if (ret)
+			return ret;
+	}
+
+	return 0;
+}
+
+static int
+dmaengine_pcm_set_runtime_hwparams(struct snd_soc_component *component,
+				   struct snd_pcm_substream *substream)
+{
+	struct snd_soc_pcm_runtime *rtd = asoc_substream_to_rtd(substream);
+	struct dmaengine_pcm *pcm = soc_component_to_pcm(component);
+	struct device *dma_dev = dmaengine_dma_dev(pcm, substream);
+	struct dma_chan *chan = pcm->chan[substream->stream];
+	struct snd_dmaengine_dai_dma_data *dma_data;
+	struct snd_pcm_hardware hw;
+
+	if (rtd->num_cpus > 1) {
+		dev_err(rtd->dev,
+			"%s doesn't support Multi CPU yet\n", __func__);
+		return -EINVAL;
+	}
+
+	if (pcm->config && pcm->config->pcm_hardware)
+		return snd_soc_set_runtime_hwparams(substream,
+				pcm->config->pcm_hardware);
+
+	dma_data = snd_soc_dai_get_dma_data(asoc_rtd_to_cpu(rtd, 0), substream);
+
+	memset(&hw, 0, sizeof(hw));
+	hw.info = SNDRV_PCM_INFO_MMAP | SNDRV_PCM_INFO_MMAP_VALID |
+			SNDRV_PCM_INFO_INTERLEAVED;
+	hw.periods_min = 2;
+	hw.periods_max = UINT_MAX;
+	hw.period_bytes_min = 256;
+	hw.period_bytes_max = dma_get_max_seg_size(dma_dev);
+	hw.buffer_bytes_max = SIZE_MAX;
+	hw.fifo_size = dma_data->fifo_size;
+
+	if (pcm->flags & SND_DMAENGINE_PCM_FLAG_NO_RESIDUE)
+		hw.info |= SNDRV_PCM_INFO_BATCH;
+
+	/**
+	 * FIXME: Remove the return value check to align with the code
+	 * before adding snd_dmaengine_pcm_refine_runtime_hwparams
+	 * function.
+	 */
+	snd_dmaengine_pcm_refine_runtime_hwparams(substream,
+						  dma_data,
+						  &hw,
+						  chan);
+
+	return snd_soc_set_runtime_hwparams(substream, &hw);
+}
+
+static int dmaengine_pcm_open(struct snd_soc_component *component,
+			      struct snd_pcm_substream *substream)
+{
+	struct dmaengine_pcm *pcm = soc_component_to_pcm(component);
+	struct dma_chan *chan = pcm->chan[substream->stream];
+	int ret;
+
+	ret = dmaengine_pcm_set_runtime_hwparams(component, substream);
+	if (ret)
+		return ret;
+
+	return snd_dmaengine_pcm_open(substream, chan);
+}
+
+static int dmaengine_pcm_close(struct snd_soc_component *component,
+			       struct snd_pcm_substream *substream)
+{
+	return snd_dmaengine_pcm_close(substream);
+}
+
+static int dmaengine_pcm_trigger(struct snd_soc_component *component,
+				 struct snd_pcm_substream *substream, int cmd)
+{
+	return snd_dmaengine_pcm_trigger(substream, cmd);
+}
+
+static struct dma_chan *dmaengine_pcm_compat_request_channel(
+	struct snd_soc_component *component,
+	struct snd_soc_pcm_runtime *rtd,
+	struct snd_pcm_substream *substream)
+{
+	struct dmaengine_pcm *pcm = soc_component_to_pcm(component);
+	struct snd_dmaengine_dai_dma_data *dma_data;
+	dma_filter_fn fn = NULL;
+
+	if (rtd->num_cpus > 1) {
+		dev_err(rtd->dev,
+			"%s doesn't support Multi CPU yet\n", __func__);
+		return NULL;
+	}
+
+	dma_data = snd_soc_dai_get_dma_data(asoc_rtd_to_cpu(rtd, 0), substream);
+
+	if ((pcm->flags & SND_DMAENGINE_PCM_FLAG_HALF_DUPLEX) && pcm->chan[0])
+		return pcm->chan[0];
+
+	if (pcm->config && pcm->config->compat_request_channel)
+		return pcm->config->compat_request_channel(rtd, substream);
+
+	if (pcm->config)
+		fn = pcm->config->compat_filter_fn;
+
+	return snd_dmaengine_pcm_request_channel(fn, dma_data->filter_data);
+}
+
+static bool dmaengine_pcm_can_report_residue(struct device *dev,
+	struct dma_chan *chan)
+{
+	struct dma_slave_caps dma_caps;
+	int ret;
+
+	ret = dma_get_slave_caps(chan, &dma_caps);
+	if (ret != 0) {
+		dev_warn(dev, "Failed to get DMA channel capabilities, falling back to period counting: %d\n",
+			 ret);
+		return false;
+	}
+
+	if (dma_caps.residue_granularity == DMA_RESIDUE_GRANULARITY_DESCRIPTOR)
+		return false;
+
+	return true;
+}
+
+static int dmaengine_pcm_new(struct snd_soc_component *component,
+			     struct snd_soc_pcm_runtime *rtd)
+{
+	struct dmaengine_pcm *pcm = soc_component_to_pcm(component);
+	const struct snd_dmaengine_pcm_config *config = pcm->config;
+	struct device *dev = component->dev;
+	struct snd_pcm_substream *substream;
+	size_t prealloc_buffer_size;
+	size_t max_buffer_size;
+	unsigned int i;
+
+	if (config && config->prealloc_buffer_size) {
+		prealloc_buffer_size = config->prealloc_buffer_size;
+		max_buffer_size = config->pcm_hardware->buffer_bytes_max;
+	} else {
+		prealloc_buffer_size = 512 * 1024;
+		max_buffer_size = SIZE_MAX;
+	}
+
+	for_each_pcm_streams(i) {
+		substream = rtd->pcm->streams[i].substream;
+		if (!substream)
+			continue;
+
+		if (!pcm->chan[i] && config && config->chan_names[i])
+			pcm->chan[i] = dma_request_slave_channel(dev,
+				config->chan_names[i]);
+
+		if (!pcm->chan[i] && (pcm->flags & SND_DMAENGINE_PCM_FLAG_COMPAT)) {
+			pcm->chan[i] = dmaengine_pcm_compat_request_channel(
+				component, rtd, substream);
+		}
+
+		if (!pcm->chan[i]) {
+			dev_err(component->dev,
+				"Missing dma channel for stream: %d\n", i);
+			return -EINVAL;
+		}
+
+		snd_pcm_set_managed_buffer(substream,
+				SNDRV_DMA_TYPE_DEV_IRAM,
+				dmaengine_dma_dev(pcm, substream),
+				prealloc_buffer_size,
+				max_buffer_size);
+
+		if (!dmaengine_pcm_can_report_residue(dev, pcm->chan[i]))
+			pcm->flags |= SND_DMAENGINE_PCM_FLAG_NO_RESIDUE;
+
+		if (rtd->pcm->streams[i].pcm->name[0] == '\0') {
+			strscpy_pad(rtd->pcm->streams[i].pcm->name,
+				    rtd->pcm->streams[i].pcm->id,
+				    sizeof(rtd->pcm->streams[i].pcm->name));
+		}
+	}
+
+	return 0;
+}
+
+static snd_pcm_uframes_t dmaengine_pcm_pointer(
+	struct snd_soc_component *component,
+	struct snd_pcm_substream *substream)
+{
+	struct dmaengine_pcm *pcm = soc_component_to_pcm(component);
+
+	if (pcm->flags & SND_DMAENGINE_PCM_FLAG_NO_RESIDUE)
+		return snd_dmaengine_pcm_pointer_no_residue(substream);
+	else
+		return snd_dmaengine_pcm_pointer(substream);
+}
+
+static int dmaengine_copy_user(struct snd_soc_component *component,
+			       struct snd_pcm_substream *substream,
+			       int channel, unsigned long hwoff,
+			       void __user *buf, unsigned long bytes)
+{
+	struct snd_pcm_runtime *runtime = substream->runtime;
+	struct dmaengine_pcm *pcm = soc_component_to_pcm(component);
+	int (*process)(struct snd_pcm_substream *substream,
+		       int channel, unsigned long hwoff,
+		       void *buf, unsigned long bytes) = pcm->config->process;
+	bool is_playback = substream->stream == SNDRV_PCM_STREAM_PLAYBACK;
+	void *dma_ptr = runtime->dma_area + hwoff +
+			channel * (runtime->dma_bytes / runtime->channels);
+	int ret;
+
+	if (is_playback)
+		if (copy_from_user(dma_ptr, buf, bytes))
+			return -EFAULT;
+
+	if (process) {
+		ret = process(substream, channel, hwoff, (__force void *)buf, bytes);
+		if (ret < 0)
+			return ret;
+	}
+
+	if (!is_playback)
+		if (copy_to_user(buf, dma_ptr, bytes))
+			return -EFAULT;
+
+	return 0;
+}
+
+static const struct snd_soc_component_driver dmaengine_pcm_component = {
+	.name		= SND_DMAENGINE_PCM_DRV_NAME,
+	.probe_order	= SND_SOC_COMP_ORDER_LATE,
+	.open		= dmaengine_pcm_open,
+	.close		= dmaengine_pcm_close,
+	.hw_params	= dmaengine_pcm_hw_params,
+	.trigger	= dmaengine_pcm_trigger,
+	.pointer	= dmaengine_pcm_pointer,
+	.pcm_construct	= dmaengine_pcm_new,
+};
+
+static const struct snd_soc_component_driver dmaengine_pcm_component_process = {
+	.name		= SND_DMAENGINE_PCM_DRV_NAME,
+	.probe_order	= SND_SOC_COMP_ORDER_LATE,
+	.open		= dmaengine_pcm_open,
+	.close		= dmaengine_pcm_close,
+	.hw_params	= dmaengine_pcm_hw_params,
+	.trigger	= dmaengine_pcm_trigger,
+	.pointer	= dmaengine_pcm_pointer,
+	.copy_user	= dmaengine_copy_user,
+	.pcm_construct	= dmaengine_pcm_new,
+};
+
+static const char * const dmaengine_pcm_dma_channel_names[] = {
+	[SNDRV_PCM_STREAM_PLAYBACK] = "tx",
+	[SNDRV_PCM_STREAM_CAPTURE] = "rx",
+};
+
+static int dmaengine_pcm_request_chan_of(struct dmaengine_pcm *pcm,
+	struct device *dev, const struct snd_dmaengine_pcm_config *config)
+{
+	unsigned int i;
+	const char *name;
+	struct dma_chan *chan;
+
+	if ((pcm->flags & SND_DMAENGINE_PCM_FLAG_NO_DT) || (!dev->of_node &&
+	    !(config && config->dma_dev && config->dma_dev->of_node)))
+		return 0;
+
+	if (config && config->dma_dev) {
+		/*
+		 * If this warning is seen, it probably means that your Linux
+		 * device structure does not match your HW device structure.
+		 * It would be best to refactor the Linux device structure to
+		 * correctly match the HW structure.
+		 */
+		dev_warn(dev, "DMA channels sourced from device %s",
+			 dev_name(config->dma_dev));
+		dev = config->dma_dev;
+	}
+
+	for_each_pcm_streams(i) {
+		if (pcm->flags & SND_DMAENGINE_PCM_FLAG_HALF_DUPLEX)
+			name = "rx-tx";
+		else
+			name = dmaengine_pcm_dma_channel_names[i];
+		if (config && config->chan_names[i])
+			name = config->chan_names[i];
+		chan = dma_request_chan(dev, name);
+		if (IS_ERR(chan)) {
+			/*
+			 * Only report probe deferral errors, channels
+			 * might not be present for devices that
+			 * support only TX or only RX.
+			 */
+			if (PTR_ERR(chan) == -EPROBE_DEFER)
+				return -EPROBE_DEFER;
+			pcm->chan[i] = NULL;
+		} else {
+			pcm->chan[i] = chan;
+		}
+		if (pcm->flags & SND_DMAENGINE_PCM_FLAG_HALF_DUPLEX)
+			break;
+	}
+
+	if (pcm->flags & SND_DMAENGINE_PCM_FLAG_HALF_DUPLEX)
+		pcm->chan[1] = pcm->chan[0];
+
+	return 0;
+}
+
+static void dmaengine_pcm_release_chan(struct dmaengine_pcm *pcm)
+{
+	unsigned int i;
+
+	for_each_pcm_streams(i) {
+		if (!pcm->chan[i])
+			continue;
+		dma_release_channel(pcm->chan[i]);
+		if (pcm->flags & SND_DMAENGINE_PCM_FLAG_HALF_DUPLEX)
+			break;
+	}
+}
+
+/**
+ * snd_dmaengine_pcm_register - Register a dmaengine based PCM device
+ * @dev: The parent device for the PCM device
+ * @config: Platform specific PCM configuration
+ * @flags: Platform specific quirks
+ */
+int snd_dmaengine_pcm_register(struct device *dev,
+	const struct snd_dmaengine_pcm_config *config, unsigned int flags)
+{
+	const struct snd_soc_component_driver *driver;
+	struct dmaengine_pcm *pcm;
+	int ret;
+
+	pcm = kzalloc(sizeof(*pcm), GFP_KERNEL);
+	if (!pcm)
+		return -ENOMEM;
+
+#ifdef CONFIG_DEBUG_FS
+	pcm->component.debugfs_prefix = "dma";
+#endif
+	pcm->config = config;
+	pcm->flags = flags;
+
+	ret = dmaengine_pcm_request_chan_of(pcm, dev, config);
+	if (ret)
+		goto err_free_dma;
+
+	if (config && config->process)
+		driver = &dmaengine_pcm_component_process;
+	else
+		driver = &dmaengine_pcm_component;
+
+	ret = snd_soc_component_initialize(&pcm->component, driver, dev);
+	if (ret)
+		goto err_free_dma;
+
+	ret = snd_soc_add_component(&pcm->component, NULL, 0);
+	if (ret)
+		goto err_free_dma;
+
+	return 0;
+
+err_free_dma:
+	dmaengine_pcm_release_chan(pcm);
+	kfree(pcm);
+	return ret;
+}
+EXPORT_SYMBOL_GPL(snd_dmaengine_pcm_register);
+
+/**
+ * snd_dmaengine_pcm_unregister - Removes a dmaengine based PCM device
+ * @dev: Parent device the PCM was register with
+ *
+ * Removes a dmaengine based PCM device previously registered with
+ * snd_dmaengine_pcm_register.
+ */
+void snd_dmaengine_pcm_unregister(struct device *dev)
+{
+	struct snd_soc_component *component;
+	struct dmaengine_pcm *pcm;
+
+	component = snd_soc_lookup_component(dev, SND_DMAENGINE_PCM_DRV_NAME);
+	if (!component)
+		return;
+
+	pcm = soc_component_to_pcm(component);
+
+	snd_soc_unregister_component_by_driver(dev, component->driver);
+	dmaengine_pcm_release_chan(pcm);
+	kfree(pcm);
+}
+EXPORT_SYMBOL_GPL(snd_dmaengine_pcm_unregister);
+
+MODULE_LICENSE("GPL");