| /* |
| * 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> |
| |
| /* |
| * 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) |
| |
| 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; |
| } |
| |
| /* |
| * If SND_DMAENGINE_PCM_DAI_FLAG_PACK is set keep |
| * hw.formats set to 0, meaning no restrictions are in place. |
| * In this case it's the responsibility of the DAI driver to |
| * provide the supported format information. |
| */ |
| if (!(dma_data->flags & SND_DMAENGINE_PCM_DAI_FLAG_PACK)) |
| /* |
| * 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 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_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_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; |
| |
| 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; |
| |
| if (!dmaengine_pcm_can_report_residue(dev, 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) || !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"); |