--- /dev/null
+/*
+ * Copyright (C) 2012, Analog Devices Inc.
+ * Author: Lars-Peter Clausen <lars@metafoo.de>
+ *
+ * Based on:
+ * imx-pcm-dma-mx2.c, Copyright 2009 Sascha Hauer <s.hauer@pengutronix.de>
+ * mxs-pcm.c, Copyright (C) 2011 Freescale Semiconductor, Inc.
+ * ep93xx-pcm.c, Copyright (C) 2006 Lennert Buytenhek <buytenh@wantstofly.org>
+ * 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 <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 <sound/dmaengine_pcm.h>
+
+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 available 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 available 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");
Code Review / kvmfornfv.git / blobdiff