/* * Copyright (C) 2012, Analog Devices Inc. * Author: Lars-Peter Clausen * * Based on: * imx-pcm-dma-mx2.c, Copyright 2009 Sascha Hauer * mxs-pcm.c, Copyright (C) 2011 Freescale Semiconductor, Inc. * ep93xx-pcm.c, Copyright (C) 2006 Lennert Buytenhek * Copyright (C) 2006 Applied Data Systems * * 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 #include #include #include #include #include #include #include struct dmaengine_pcm_runtime_data { struct dma_chan *dma_chan; dma_cookie_t cookie; unsigned int pos; }; static inline struct dmaengine_pcm_runtime_data *substream_to_prtd( const struct snd_pcm_substream *substream) { return substream->runtime->private_data; } struct dma_chan *snd_dmaengine_pcm_get_chan(struct snd_pcm_substream *substream) { struct dmaengine_pcm_runtime_data *prtd = substream_to_prtd(substream); return prtd->dma_chan; } EXPORT_SYMBOL_GPL(snd_dmaengine_pcm_get_chan); /** * snd_hwparams_to_dma_slave_config - Convert hw_params to dma_slave_config * @substream: PCM substream * @params: hw_params * @slave_config: DMA slave config * * This function can be used to initialize a dma_slave_config from a substream * and hw_params in a dmaengine based PCM driver implementation. */ int snd_hwparams_to_dma_slave_config(const struct snd_pcm_substream *substream, const struct snd_pcm_hw_params *params, struct dma_slave_config *slave_config) { enum dma_slave_buswidth buswidth; int bits; bits = params_physical_width(params); if (bits < 8 || bits > 64) return -EINVAL; else if (bits == 8) buswidth = DMA_SLAVE_BUSWIDTH_1_BYTE; else if (bits == 16) buswidth = DMA_SLAVE_BUSWIDTH_2_BYTES; else if (bits == 24) buswidth = DMA_SLAVE_BUSWIDTH_3_BYTES; else if (bits <= 32) buswidth = DMA_SLAVE_BUSWIDTH_4_BYTES; else buswidth = DMA_SLAVE_BUSWIDTH_8_BYTES; if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK) { slave_config->direction = DMA_MEM_TO_DEV; slave_config->dst_addr_width = buswidth; } else { slave_config->direction = DMA_DEV_TO_MEM; slave_config->src_addr_width = buswidth; } slave_config->device_fc = false; return 0; } EXPORT_SYMBOL_GPL(snd_hwparams_to_dma_slave_config); /** * snd_dmaengine_pcm_set_config_from_dai_data() - Initializes a dma slave config * using DAI DMA data. * @substream: PCM substream * @dma_data: DAI DMA data * @slave_config: DMA slave configuration * * Initializes the {dst,src}_addr, {dst,src}_maxburst, {dst,src}_addr_width and * slave_id fields of the DMA slave config from the same fields of the DAI DMA * data struct. The src and dst fields will be initialized depending on the * direction of the substream. If the substream is a playback stream the dst * fields will be initialized, if it is a capture stream the src fields will be * initialized. The {dst,src}_addr_width field will only be initialized if the * addr_width field of the DAI DMA data struct is not equal to * DMA_SLAVE_BUSWIDTH_UNDEFINED. */ void snd_dmaengine_pcm_set_config_from_dai_data( const struct snd_pcm_substream *substream, const struct snd_dmaengine_dai_dma_data *dma_data, struct dma_slave_config *slave_config) { if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK) { slave_config->dst_addr = dma_data->addr; slave_config->dst_maxburst = dma_data->maxburst; if (dma_data->addr_width != DMA_SLAVE_BUSWIDTH_UNDEFINED) slave_config->dst_addr_width = dma_data->addr_width; } else { slave_config->src_addr = dma_data->addr; slave_config->src_maxburst = dma_data->maxburst; if (dma_data->addr_width != DMA_SLAVE_BUSWIDTH_UNDEFINED) slave_config->src_addr_width = dma_data->addr_width; } slave_config->slave_id = dma_data->slave_id; } EXPORT_SYMBOL_GPL(snd_dmaengine_pcm_set_config_from_dai_data); static void dmaengine_pcm_dma_complete(void *arg) { struct snd_pcm_substream *substream = arg; struct dmaengine_pcm_runtime_data *prtd = substream_to_prtd(substream); prtd->pos += snd_pcm_lib_period_bytes(substream); if (prtd->pos >= snd_pcm_lib_buffer_bytes(substream)) prtd->pos = 0; snd_pcm_period_elapsed(substream); } static int dmaengine_pcm_prepare_and_submit(struct snd_pcm_substream *substream) { struct dmaengine_pcm_runtime_data *prtd = substream_to_prtd(substream); struct dma_chan *chan = prtd->dma_chan; struct dma_async_tx_descriptor *desc; enum dma_transfer_direction direction; unsigned long flags = DMA_CTRL_ACK; direction = snd_pcm_substream_to_dma_direction(substream); if (!substream->runtime->no_period_wakeup) flags |= DMA_PREP_INTERRUPT; prtd->pos = 0; desc = dmaengine_prep_dma_cyclic(chan, substream->runtime->dma_addr, snd_pcm_lib_buffer_bytes(substream), snd_pcm_lib_period_bytes(substream), direction, flags); if (!desc) return -ENOMEM; desc->callback = dmaengine_pcm_dma_complete; desc->callback_param = substream; prtd->cookie = dmaengine_submit(desc); return 0; } /** * snd_dmaengine_pcm_trigger - dmaengine based PCM trigger implementation * @substream: PCM substream * @cmd: Trigger command * * Returns 0 on success, a negative error code otherwise. * * This function can be used as the PCM trigger callback for dmaengine based PCM * driver implementations. */ int snd_dmaengine_pcm_trigger(struct snd_pcm_substream *substream, int cmd) { struct dmaengine_pcm_runtime_data *prtd = substream_to_prtd(substream); struct snd_pcm_runtime *runtime = substream->runtime; int ret; switch (cmd) { case SNDRV_PCM_TRIGGER_START: ret = dmaengine_pcm_prepare_and_submit(substream); if (ret) return ret; dma_async_issue_pending(prtd->dma_chan); break; case SNDRV_PCM_TRIGGER_RESUME: case SNDRV_PCM_TRIGGER_PAUSE_RELEASE: dmaengine_resume(prtd->dma_chan); break; case SNDRV_PCM_TRIGGER_SUSPEND: if (runtime->info & SNDRV_PCM_INFO_PAUSE) dmaengine_pause(prtd->dma_chan); else dmaengine_terminate_all(prtd->dma_chan); break; case SNDRV_PCM_TRIGGER_PAUSE_PUSH: dmaengine_pause(prtd->dma_chan); break; case SNDRV_PCM_TRIGGER_STOP: dmaengine_terminate_all(prtd->dma_chan); break; default: return -EINVAL; } return 0; } EXPORT_SYMBOL_GPL(snd_dmaengine_pcm_trigger); /** * snd_dmaengine_pcm_pointer_no_residue - dmaengine based PCM pointer implementation * @substream: PCM substream * * This function is deprecated and should not be used by new drivers, as its * results may be unreliable. */ snd_pcm_uframes_t snd_dmaengine_pcm_pointer_no_residue(struct snd_pcm_substream *substream) { struct dmaengine_pcm_runtime_data *prtd = substream_to_prtd(substream); return bytes_to_frames(substream->runtime, prtd->pos); } EXPORT_SYMBOL_GPL(snd_dmaengine_pcm_pointer_no_residue); /** * snd_dmaengine_pcm_pointer - dmaengine based PCM pointer implementation * @substream: PCM substream * * This function can be used as the PCM pointer callback for dmaengine based PCM * driver implementations. */ snd_pcm_uframes_t snd_dmaengine_pcm_pointer(struct snd_pcm_substream *substream) { struct dmaengine_pcm_runtime_data *prtd = substream_to_prtd(substream); struct dma_tx_state state; enum dma_status status; unsigned int buf_size; unsigned int pos = 0; status = dmaengine_tx_status(prtd->dma_chan, prtd->cookie, &state); if (status == DMA_IN_PROGRESS || status == DMA_PAUSED) { buf_size = snd_pcm_lib_buffer_bytes(substream); if (state.residue > 0 && state.residue <= buf_size) pos = buf_size - state.residue; } return bytes_to_frames(substream->runtime, pos); } EXPORT_SYMBOL_GPL(snd_dmaengine_pcm_pointer); /** * snd_dmaengine_pcm_request_channel - Request channel for the dmaengine PCM * @filter_fn: Filter function used to request the DMA channel * @filter_data: Data passed to the DMA filter function * * Returns NULL or the requested DMA channel. * * This function request a DMA channel for usage with dmaengine PCM. */ struct dma_chan *snd_dmaengine_pcm_request_channel(dma_filter_fn filter_fn, void *filter_data) { dma_cap_mask_t mask; dma_cap_zero(mask); dma_cap_set(DMA_SLAVE, mask); dma_cap_set(DMA_CYCLIC, mask); return dma_request_channel(mask, filter_fn, filter_data); } EXPORT_SYMBOL_GPL(snd_dmaengine_pcm_request_channel); /** * snd_dmaengine_pcm_open - Open a dmaengine based PCM substream * @substream: PCM substream * @chan: DMA channel to use for data transfers * * Returns 0 on success, a negative error code otherwise. * * The function should usually be called from the pcm open callback. Note that * this function will use private_data field of the substream's runtime. So it * is not availabe to your pcm driver implementation. */ int snd_dmaengine_pcm_open(struct snd_pcm_substream *substream, struct dma_chan *chan) { struct dmaengine_pcm_runtime_data *prtd; int ret; if (!chan) return -ENXIO; ret = snd_pcm_hw_constraint_integer(substream->runtime, SNDRV_PCM_HW_PARAM_PERIODS); if (ret < 0) return ret; prtd = kzalloc(sizeof(*prtd), GFP_KERNEL); if (!prtd) return -ENOMEM; prtd->dma_chan = chan; substream->runtime->private_data = prtd; return 0; } EXPORT_SYMBOL_GPL(snd_dmaengine_pcm_open); /** * snd_dmaengine_pcm_open_request_chan - Open a dmaengine based PCM substream and request channel * @substream: PCM substream * @filter_fn: Filter function used to request the DMA channel * @filter_data: Data passed to the DMA filter function * * Returns 0 on success, a negative error code otherwise. * * This function will request a DMA channel using the passed filter function and * data. The function should usually be called from the pcm open callback. Note * that this function will use private_data field of the substream's runtime. So * it is not availabe to your pcm driver implementation. */ int snd_dmaengine_pcm_open_request_chan(struct snd_pcm_substream *substream, dma_filter_fn filter_fn, void *filter_data) { return snd_dmaengine_pcm_open(substream, snd_dmaengine_pcm_request_channel(filter_fn, filter_data)); } EXPORT_SYMBOL_GPL(snd_dmaengine_pcm_open_request_chan); /** * snd_dmaengine_pcm_close - Close a dmaengine based PCM substream * @substream: PCM substream */ int snd_dmaengine_pcm_close(struct snd_pcm_substream *substream) { struct dmaengine_pcm_runtime_data *prtd = substream_to_prtd(substream); kfree(prtd); return 0; } EXPORT_SYMBOL_GPL(snd_dmaengine_pcm_close); /** * snd_dmaengine_pcm_release_chan_close - Close a dmaengine based PCM substream and release channel * @substream: PCM substream * * Releases the DMA channel associated with the PCM substream. */ int snd_dmaengine_pcm_close_release_chan(struct snd_pcm_substream *substream) { struct dmaengine_pcm_runtime_data *prtd = substream_to_prtd(substream); dma_release_channel(prtd->dma_chan); return snd_dmaengine_pcm_close(substream); } EXPORT_SYMBOL_GPL(snd_dmaengine_pcm_close_release_chan); MODULE_LICENSE("GPL");