--- /dev/null
+/*
+ * Copyright (C) 2013, Analog Devices Inc.
+ * Author: Lars-Peter Clausen <lars@metafoo.de>
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License as published by the
+ * Free Software Foundation; either version 2 of the License, or (at your
+ * option) any later version.
+ *
+ * You should have received a copy of the GNU General Public License along
+ * with this program; if not, write to the Free Software Foundation, Inc.,
+ * 675 Mass Ave, Cambridge, MA 02139, USA.
+ *
+ */
+#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>
+
+struct dmaengine_pcm {
+ struct dma_chan *chan[SNDRV_PCM_STREAM_LAST + 1];
+ const struct snd_dmaengine_pcm_config *config;
+ struct snd_soc_platform platform;
+ unsigned int flags;
+};
+
+static struct dmaengine_pcm *soc_platform_to_pcm(struct snd_soc_platform *p)
+{
+ return container_of(p, struct dmaengine_pcm, platform);
+}
+
+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 = substream->private_data;
+ struct snd_dmaengine_dai_dma_data *dma_data;
+ int ret;
+
+ dma_data = snd_soc_dai_get_dma_data(rtd->cpu_dai, 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_pcm_substream *substream,
+ struct snd_pcm_hw_params *params)
+{
+ struct snd_soc_pcm_runtime *rtd = substream->private_data;
+ struct dmaengine_pcm *pcm = soc_platform_to_pcm(rtd->platform);
+ 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 snd_pcm_lib_malloc_pages(substream, params_buffer_bytes(params));
+}
+
+static int dmaengine_pcm_set_runtime_hwparams(struct snd_pcm_substream *substream)
+{
+ struct snd_soc_pcm_runtime *rtd = substream->private_data;
+ struct dmaengine_pcm *pcm = soc_platform_to_pcm(rtd->platform);
+ 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 dma_slave_caps dma_caps;
+ struct snd_pcm_hardware hw;
+ u32 addr_widths = BIT(DMA_SLAVE_BUSWIDTH_1_BYTE) |
+ BIT(DMA_SLAVE_BUSWIDTH_2_BYTES) |
+ BIT(DMA_SLAVE_BUSWIDTH_4_BYTES);
+ int i, ret;
+
+ 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(rtd->cpu_dai, 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;
+
+ ret = dma_get_slave_caps(chan, &dma_caps);
+ if (ret == 0) {
+ if (dma_caps.cmd_pause)
+ hw.info |= SNDRV_PCM_INFO_PAUSE | SNDRV_PCM_INFO_RESUME;
+ if (dma_caps.residue_granularity <= DMA_RESIDUE_GRANULARITY_SEGMENT)
+ hw.info |= SNDRV_PCM_INFO_BATCH;
+
+ if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK)
+ addr_widths = dma_caps.dst_addr_widths;
+ else
+ addr_widths = dma_caps.src_addr_widths;
+ }
+
+ /*
+ * Prepare formats mask for valid/allowed sample types. If the dma does
+ * not have support for the given physical word size, it needs to be
+ * masked out so user space can not use the format which produces
+ * corrupted audio.
+ * In case the dma driver does not implement the slave_caps the default
+ * assumption is that it supports 1, 2 and 4 bytes widths.
+ */
+ for (i = 0; i <= SNDRV_PCM_FORMAT_LAST; i++) {
+ int bits = snd_pcm_format_physical_width(i);
+
+ /* Enable only samples with DMA supported physical widths */
+ switch (bits) {
+ case 8:
+ case 16:
+ case 24:
+ case 32:
+ case 64:
+ if (addr_widths & (1 << (bits / 8)))
+ hw.formats |= (1LL << i);
+ break;
+ default:
+ /* Unsupported types */
+ break;
+ }
+ }
+
+ return snd_soc_set_runtime_hwparams(substream, &hw);
+}
+
+static int dmaengine_pcm_open(struct snd_pcm_substream *substream)
+{
+ struct snd_soc_pcm_runtime *rtd = substream->private_data;
+ struct dmaengine_pcm *pcm = soc_platform_to_pcm(rtd->platform);
+ struct dma_chan *chan = pcm->chan[substream->stream];
+ int ret;
+
+ ret = dmaengine_pcm_set_runtime_hwparams(substream);
+ if (ret)
+ return ret;
+
+ return snd_dmaengine_pcm_open(substream, chan);
+}
+
+static struct dma_chan *dmaengine_pcm_compat_request_channel(
+ struct snd_soc_pcm_runtime *rtd,
+ struct snd_pcm_substream *substream)
+{
+ struct dmaengine_pcm *pcm = soc_platform_to_pcm(rtd->platform);
+ struct snd_dmaengine_dai_dma_data *dma_data;
+ dma_filter_fn fn = NULL;
+
+ dma_data = snd_soc_dai_get_dma_data(rtd->cpu_dai, 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 dma_chan *chan)
+{
+ struct dma_slave_caps dma_caps;
+ int ret;
+
+ ret = dma_get_slave_caps(chan, &dma_caps);
+ if (ret != 0)
+ return true;
+
+ if (dma_caps.residue_granularity == DMA_RESIDUE_GRANULARITY_DESCRIPTOR)
+ return false;
+
+ return true;
+}
+
+static int dmaengine_pcm_new(struct snd_soc_pcm_runtime *rtd)
+{
+ struct dmaengine_pcm *pcm = soc_platform_to_pcm(rtd->platform);
+ const struct snd_dmaengine_pcm_config *config = pcm->config;
+ struct device *dev = rtd->platform->dev;
+ struct snd_dmaengine_dai_dma_data *dma_data;
+ struct snd_pcm_substream *substream;
+ size_t prealloc_buffer_size;
+ size_t max_buffer_size;
+ unsigned int i;
+ int ret;
+
+ 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 (i = SNDRV_PCM_STREAM_PLAYBACK; i <= SNDRV_PCM_STREAM_CAPTURE; i++) {
+ substream = rtd->pcm->streams[i].substream;
+ if (!substream)
+ continue;
+
+ dma_data = snd_soc_dai_get_dma_data(rtd->cpu_dai, substream);
+
+ if (!pcm->chan[i] &&
+ (pcm->flags & SND_DMAENGINE_PCM_FLAG_CUSTOM_CHANNEL_NAME))
+ pcm->chan[i] = dma_request_slave_channel(dev,
+ dma_data->chan_name);
+
+ if (!pcm->chan[i] && (pcm->flags & SND_DMAENGINE_PCM_FLAG_COMPAT)) {
+ pcm->chan[i] = dmaengine_pcm_compat_request_channel(rtd,
+ substream);
+ }
+
+ if (!pcm->chan[i]) {
+ dev_err(rtd->platform->dev,
+ "Missing dma channel for stream: %d\n", i);
+ return -EINVAL;
+ }
+
+ ret = snd_pcm_lib_preallocate_pages(substream,
+ SNDRV_DMA_TYPE_DEV_IRAM,
+ dmaengine_dma_dev(pcm, substream),
+ prealloc_buffer_size,
+ max_buffer_size);
+ if (ret)
+ return ret;
+
+ /*
+ * This will only return false if we know for sure that at least
+ * one channel does not support residue reporting. If the DMA
+ * driver does not implement the slave_caps API we rely having
+ * the NO_RESIDUE flag set manually in case residue reporting is
+ * not supported.
+ */
+ if (!dmaengine_pcm_can_report_residue(pcm->chan[i]))
+ pcm->flags |= SND_DMAENGINE_PCM_FLAG_NO_RESIDUE;
+ }
+
+ return 0;
+}
+
+static snd_pcm_uframes_t dmaengine_pcm_pointer(
+ struct snd_pcm_substream *substream)
+{
+ struct snd_soc_pcm_runtime *rtd = substream->private_data;
+ struct dmaengine_pcm *pcm = soc_platform_to_pcm(rtd->platform);
+
+ 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 const struct snd_pcm_ops dmaengine_pcm_ops = {
+ .open = dmaengine_pcm_open,
+ .close = snd_dmaengine_pcm_close,
+ .ioctl = snd_pcm_lib_ioctl,
+ .hw_params = dmaengine_pcm_hw_params,
+ .hw_free = snd_pcm_lib_free_pages,
+ .trigger = snd_dmaengine_pcm_trigger,
+ .pointer = dmaengine_pcm_pointer,
+};
+
+static const struct snd_soc_platform_driver dmaengine_pcm_platform = {
+ .component_driver = {
+ .probe_order = SND_SOC_COMP_ORDER_LATE,
+ },
+ .ops = &dmaengine_pcm_ops,
+ .pcm_new = 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 |
+ SND_DMAENGINE_PCM_FLAG_CUSTOM_CHANNEL_NAME)) ||
+ !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 (i = SNDRV_PCM_STREAM_PLAYBACK; i <= SNDRV_PCM_STREAM_CAPTURE;
+ 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_slave_channel_reason(dev, name);
+ if (IS_ERR(chan)) {
+ 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 (i = SNDRV_PCM_STREAM_PLAYBACK; i <= SNDRV_PCM_STREAM_CAPTURE;
+ 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)
+{
+ struct dmaengine_pcm *pcm;
+ int ret;
+
+ pcm = kzalloc(sizeof(*pcm), GFP_KERNEL);
+ if (!pcm)
+ return -ENOMEM;
+
+ pcm->config = config;
+ pcm->flags = flags;
+
+ ret = dmaengine_pcm_request_chan_of(pcm, dev, config);
+ if (ret)
+ goto err_free_dma;
+
+ ret = snd_soc_add_platform(dev, &pcm->platform,
+ &dmaengine_pcm_platform);
+ 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_platform *platform;
+ struct dmaengine_pcm *pcm;
+
+ platform = snd_soc_lookup_platform(dev);
+ if (!platform)
+ return;
+
+ pcm = soc_platform_to_pcm(platform);
+
+ snd_soc_remove_platform(platform);
+ dmaengine_pcm_release_chan(pcm);
+ kfree(pcm);
+}
+EXPORT_SYMBOL_GPL(snd_dmaengine_pcm_unregister);
+
+MODULE_LICENSE("GPL");
Code Review / kvmfornfv.git / blobdiff