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v5.14.15
  1// SPDX-License-Identifier: GPL-2.0-or-later
  2/*
  3 * atmel-pcm-dma.c  --  ALSA PCM DMA support for the Atmel SoC.
  4 *
  5 *  Copyright (C) 2012 Atmel
  6 *
  7 * Author: Bo Shen <voice.shen@atmel.com>
  8 *
  9 * Based on atmel-pcm by:
 10 * Sedji Gaouaou <sedji.gaouaou@atmel.com>
 11 * Copyright 2008 Atmel
 12 */
 13
 14#include <linux/module.h>
 15#include <linux/init.h>
 16#include <linux/platform_device.h>
 17#include <linux/slab.h>
 18#include <linux/dma-mapping.h>
 19#include <linux/dmaengine.h>
 20#include <linux/atmel-ssc.h>
 
 21
 22#include <sound/core.h>
 23#include <sound/pcm.h>
 24#include <sound/pcm_params.h>
 25#include <sound/soc.h>
 26#include <sound/dmaengine_pcm.h>
 27
 28#include "atmel-pcm.h"
 29
 30/*--------------------------------------------------------------------------*\
 31 * Hardware definition
 32\*--------------------------------------------------------------------------*/
 33static const struct snd_pcm_hardware atmel_pcm_dma_hardware = {
 34	.info			= SNDRV_PCM_INFO_MMAP |
 35				  SNDRV_PCM_INFO_MMAP_VALID |
 36				  SNDRV_PCM_INFO_INTERLEAVED |
 37				  SNDRV_PCM_INFO_RESUME |
 38				  SNDRV_PCM_INFO_PAUSE,
 39	.period_bytes_min	= 256,		/* lighting DMA overhead */
 40	.period_bytes_max	= 2 * 0xffff,	/* if 2 bytes format */
 41	.periods_min		= 8,
 42	.periods_max		= 1024,		/* no limit */
 43	.buffer_bytes_max	= 512 * 1024,
 44};
 45
 46/*
 47 * atmel_pcm_dma_irq: SSC interrupt handler for DMAENGINE enabled SSC
 48 *
 49 * We use DMAENGINE to send/receive data to/from SSC so this ISR is only to
 50 * check if any overrun occured.
 51 */
 52static void atmel_pcm_dma_irq(u32 ssc_sr,
 53	struct snd_pcm_substream *substream)
 54{
 55	struct snd_soc_pcm_runtime *rtd = asoc_substream_to_rtd(substream);
 56	struct atmel_pcm_dma_params *prtd;
 57
 58	prtd = snd_soc_dai_get_dma_data(asoc_rtd_to_cpu(rtd, 0), substream);
 59
 60	if (ssc_sr & prtd->mask->ssc_error) {
 61		if (snd_pcm_running(substream))
 62			pr_warn("atmel-pcm: buffer %s on %s (SSC_SR=%#x)\n",
 63				substream->stream == SNDRV_PCM_STREAM_PLAYBACK
 64				? "underrun" : "overrun", prtd->name,
 65				ssc_sr);
 66
 67		/* stop RX and capture: will be enabled again at restart */
 68		ssc_writex(prtd->ssc->regs, SSC_CR, prtd->mask->ssc_disable);
 69		snd_pcm_stop_xrun(substream);
 70
 71		/* now drain RHR and read status to remove xrun condition */
 72		ssc_readx(prtd->ssc->regs, SSC_RHR);
 73		ssc_readx(prtd->ssc->regs, SSC_SR);
 74	}
 75}
 76
 77static int atmel_pcm_configure_dma(struct snd_pcm_substream *substream,
 78	struct snd_pcm_hw_params *params, struct dma_slave_config *slave_config)
 79{
 80	struct snd_soc_pcm_runtime *rtd = asoc_substream_to_rtd(substream);
 81	struct atmel_pcm_dma_params *prtd;
 82	struct ssc_device *ssc;
 83	int ret;
 84
 85	prtd = snd_soc_dai_get_dma_data(asoc_rtd_to_cpu(rtd, 0), substream);
 86	ssc = prtd->ssc;
 87
 88	ret = snd_hwparams_to_dma_slave_config(substream, params, slave_config);
 89	if (ret) {
 90		pr_err("atmel-pcm: hwparams to dma slave configure failed\n");
 91		return ret;
 92	}
 93
 94	slave_config->dst_addr = ssc->phybase + SSC_THR;
 95	slave_config->dst_maxburst = 1;
 96
 97	slave_config->src_addr = ssc->phybase + SSC_RHR;
 98	slave_config->src_maxburst = 1;
 99
100	prtd->dma_intr_handler = atmel_pcm_dma_irq;
101
102	return 0;
103}
104
105static const struct snd_dmaengine_pcm_config atmel_dmaengine_pcm_config = {
106	.prepare_slave_config = atmel_pcm_configure_dma,
107	.pcm_hardware = &atmel_pcm_dma_hardware,
108	.prealloc_buffer_size = 64 * 1024,
109};
110
111int atmel_pcm_dma_platform_register(struct device *dev)
112{
113	return devm_snd_dmaengine_pcm_register(dev,
114					&atmel_dmaengine_pcm_config, 0);
115}
116EXPORT_SYMBOL(atmel_pcm_dma_platform_register);
117
118MODULE_AUTHOR("Bo Shen <voice.shen@atmel.com>");
119MODULE_DESCRIPTION("Atmel DMA based PCM module");
120MODULE_LICENSE("GPL");
v5.9
  1// SPDX-License-Identifier: GPL-2.0-or-later
  2/*
  3 * atmel-pcm-dma.c  --  ALSA PCM DMA support for the Atmel SoC.
  4 *
  5 *  Copyright (C) 2012 Atmel
  6 *
  7 * Author: Bo Shen <voice.shen@atmel.com>
  8 *
  9 * Based on atmel-pcm by:
 10 * Sedji Gaouaou <sedji.gaouaou@atmel.com>
 11 * Copyright 2008 Atmel
 12 */
 13
 14#include <linux/module.h>
 15#include <linux/init.h>
 16#include <linux/platform_device.h>
 17#include <linux/slab.h>
 18#include <linux/dma-mapping.h>
 19#include <linux/dmaengine.h>
 20#include <linux/atmel-ssc.h>
 21#include <linux/platform_data/dma-atmel.h>
 22
 23#include <sound/core.h>
 24#include <sound/pcm.h>
 25#include <sound/pcm_params.h>
 26#include <sound/soc.h>
 27#include <sound/dmaengine_pcm.h>
 28
 29#include "atmel-pcm.h"
 30
 31/*--------------------------------------------------------------------------*\
 32 * Hardware definition
 33\*--------------------------------------------------------------------------*/
 34static const struct snd_pcm_hardware atmel_pcm_dma_hardware = {
 35	.info			= SNDRV_PCM_INFO_MMAP |
 36				  SNDRV_PCM_INFO_MMAP_VALID |
 37				  SNDRV_PCM_INFO_INTERLEAVED |
 38				  SNDRV_PCM_INFO_RESUME |
 39				  SNDRV_PCM_INFO_PAUSE,
 40	.period_bytes_min	= 256,		/* lighting DMA overhead */
 41	.period_bytes_max	= 2 * 0xffff,	/* if 2 bytes format */
 42	.periods_min		= 8,
 43	.periods_max		= 1024,		/* no limit */
 44	.buffer_bytes_max	= 512 * 1024,
 45};
 46
 47/*
 48 * atmel_pcm_dma_irq: SSC interrupt handler for DMAENGINE enabled SSC
 49 *
 50 * We use DMAENGINE to send/receive data to/from SSC so this ISR is only to
 51 * check if any overrun occured.
 52 */
 53static void atmel_pcm_dma_irq(u32 ssc_sr,
 54	struct snd_pcm_substream *substream)
 55{
 56	struct snd_soc_pcm_runtime *rtd = asoc_substream_to_rtd(substream);
 57	struct atmel_pcm_dma_params *prtd;
 58
 59	prtd = snd_soc_dai_get_dma_data(asoc_rtd_to_cpu(rtd, 0), substream);
 60
 61	if (ssc_sr & prtd->mask->ssc_error) {
 62		if (snd_pcm_running(substream))
 63			pr_warn("atmel-pcm: buffer %s on %s (SSC_SR=%#x)\n",
 64				substream->stream == SNDRV_PCM_STREAM_PLAYBACK
 65				? "underrun" : "overrun", prtd->name,
 66				ssc_sr);
 67
 68		/* stop RX and capture: will be enabled again at restart */
 69		ssc_writex(prtd->ssc->regs, SSC_CR, prtd->mask->ssc_disable);
 70		snd_pcm_stop_xrun(substream);
 71
 72		/* now drain RHR and read status to remove xrun condition */
 73		ssc_readx(prtd->ssc->regs, SSC_RHR);
 74		ssc_readx(prtd->ssc->regs, SSC_SR);
 75	}
 76}
 77
 78static int atmel_pcm_configure_dma(struct snd_pcm_substream *substream,
 79	struct snd_pcm_hw_params *params, struct dma_slave_config *slave_config)
 80{
 81	struct snd_soc_pcm_runtime *rtd = asoc_substream_to_rtd(substream);
 82	struct atmel_pcm_dma_params *prtd;
 83	struct ssc_device *ssc;
 84	int ret;
 85
 86	prtd = snd_soc_dai_get_dma_data(asoc_rtd_to_cpu(rtd, 0), substream);
 87	ssc = prtd->ssc;
 88
 89	ret = snd_hwparams_to_dma_slave_config(substream, params, slave_config);
 90	if (ret) {
 91		pr_err("atmel-pcm: hwparams to dma slave configure failed\n");
 92		return ret;
 93	}
 94
 95	slave_config->dst_addr = ssc->phybase + SSC_THR;
 96	slave_config->dst_maxburst = 1;
 97
 98	slave_config->src_addr = ssc->phybase + SSC_RHR;
 99	slave_config->src_maxburst = 1;
100
101	prtd->dma_intr_handler = atmel_pcm_dma_irq;
102
103	return 0;
104}
105
106static const struct snd_dmaengine_pcm_config atmel_dmaengine_pcm_config = {
107	.prepare_slave_config = atmel_pcm_configure_dma,
108	.pcm_hardware = &atmel_pcm_dma_hardware,
109	.prealloc_buffer_size = 64 * 1024,
110};
111
112int atmel_pcm_dma_platform_register(struct device *dev)
113{
114	return devm_snd_dmaengine_pcm_register(dev,
115					&atmel_dmaengine_pcm_config, 0);
116}
117EXPORT_SYMBOL(atmel_pcm_dma_platform_register);
118
119MODULE_AUTHOR("Bo Shen <voice.shen@atmel.com>");
120MODULE_DESCRIPTION("Atmel DMA based PCM module");
121MODULE_LICENSE("GPL");