| // 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> |
| |
| static unsigned int prealloc_buffer_size_kbytes = 512; |
| module_param(prealloc_buffer_size_kbytes, uint, 0444); |
| MODULE_PARM_DESC(prealloc_buffer_size_kbytes, "Preallocate DMA buffer size (KB)."); |
| |
| /* |
| * 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); |
| struct dma_slave_config slave_config; |
| int ret; |
| |
| if (!pcm->config->prepare_slave_config) |
| return 0; |
| |
| memset(&slave_config, 0, sizeof(slave_config)); |
| |
| ret = pcm->config->prepare_slave_config(substream, params, &slave_config); |
| if (ret) |
| return ret; |
| |
| return dmaengine_slave_config(chan, &slave_config); |
| } |
| |
| 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_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 = dma_data->maxburst * DMA_SLAVE_BUSWIDTH_8_BYTES; |
| if (!hw.period_bytes_min) |
| 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; |
| |
| 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->compat_request_channel) |
| return pcm->config->compat_request_channel(rtd, substream); |
| |
| return snd_dmaengine_pcm_request_channel(pcm->config->compat_filter_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; |
| size_t prealloc_buffer_size; |
| size_t max_buffer_size; |
| unsigned int i; |
| |
| if (config->prealloc_buffer_size) |
| prealloc_buffer_size = config->prealloc_buffer_size; |
| else |
| prealloc_buffer_size = prealloc_buffer_size_kbytes * 1024; |
| |
| if (config->pcm_hardware && config->pcm_hardware->buffer_bytes_max) |
| max_buffer_size = config->pcm_hardware->buffer_bytes_max; |
| else |
| max_buffer_size = SIZE_MAX; |
| |
| for_each_pcm_streams(i) { |
| struct snd_pcm_substream *substream = rtd->pcm->streams[i].substream; |
| if (!substream) |
| continue; |
| |
| if (!pcm->chan[i] && 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); |
| |
| if (is_playback) |
| if (copy_from_user(dma_ptr, buf, bytes)) |
| return -EFAULT; |
| |
| if (process) { |
| int 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->dma_dev && config->dma_dev->of_node))) |
| return 0; |
| |
| if (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->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; |
| } |
| } |
| |
| static const struct snd_dmaengine_pcm_config snd_dmaengine_pcm_default_config = { |
| .prepare_slave_config = snd_dmaengine_pcm_prepare_slave_config, |
| }; |
| |
| /** |
| * 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 |
| if (!config) |
| config = &snd_dmaengine_pcm_default_config; |
| pcm->config = config; |
| pcm->flags = flags; |
| |
| ret = dmaengine_pcm_request_chan_of(pcm, dev, config); |
| if (ret) |
| goto err_free_dma; |
| |
| if (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"); |