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1// SPDX-License-Identifier: GPL-2.0-only2/*3 * Au1000/Au1500/Au1100 Audio DMA support.4 *5 * (c) 2011 Manuel Lauss <manuel.lauss@googlemail.com>6 *7 * copied almost verbatim from the old ALSA driver, written by8 * Charles Eidsness <charles@cooper-street.com>9 */10 11#include <linux/module.h>12#include <linux/init.h>13#include <linux/platform_device.h>14#include <linux/slab.h>15#include <linux/dma-mapping.h>16#include <sound/core.h>17#include <sound/pcm.h>18#include <sound/pcm_params.h>19#include <sound/soc.h>20#include <asm/mach-au1x00/au1000.h>21#include <asm/mach-au1x00/au1000_dma.h>22 23#include "psc.h"24 25#define DRV_NAME "au1x_dma"26 27struct pcm_period {28 u32 start;29 u32 relative_end; /* relative to start of buffer */30 struct pcm_period *next;31};32 33struct audio_stream {34 struct snd_pcm_substream *substream;35 int dma;36 struct pcm_period *buffer;37 unsigned int period_size;38 unsigned int periods;39};40 41struct alchemy_pcm_ctx {42 struct audio_stream stream[2]; /* playback & capture */43};44 45static void au1000_release_dma_link(struct audio_stream *stream)46{47 struct pcm_period *pointer;48 struct pcm_period *pointer_next;49 50 stream->period_size = 0;51 stream->periods = 0;52 pointer = stream->buffer;53 if (!pointer)54 return;55 do {56 pointer_next = pointer->next;57 kfree(pointer);58 pointer = pointer_next;59 } while (pointer != stream->buffer);60 stream->buffer = NULL;61}62 63static int au1000_setup_dma_link(struct audio_stream *stream,64 unsigned int period_bytes,65 unsigned int periods)66{67 struct snd_pcm_substream *substream = stream->substream;68 struct snd_pcm_runtime *runtime = substream->runtime;69 struct pcm_period *pointer;70 unsigned long dma_start;71 int i;72 73 dma_start = virt_to_phys(runtime->dma_area);74 75 if (stream->period_size == period_bytes &&76 stream->periods == periods)77 return 0; /* not changed */78 79 au1000_release_dma_link(stream);80 81 stream->period_size = period_bytes;82 stream->periods = periods;83 84 stream->buffer = kmalloc(sizeof(struct pcm_period), GFP_KERNEL);85 if (!stream->buffer)86 return -ENOMEM;87 pointer = stream->buffer;88 for (i = 0; i < periods; i++) {89 pointer->start = (u32)(dma_start + (i * period_bytes));90 pointer->relative_end = (u32) (((i+1) * period_bytes) - 0x1);91 if (i < periods - 1) {92 pointer->next = kmalloc(sizeof(struct pcm_period),93 GFP_KERNEL);94 if (!pointer->next) {95 au1000_release_dma_link(stream);96 return -ENOMEM;97 }98 pointer = pointer->next;99 }100 }101 pointer->next = stream->buffer;102 return 0;103}104 105static void au1000_dma_stop(struct audio_stream *stream)106{107 if (stream->buffer)108 disable_dma(stream->dma);109}110 111static void au1000_dma_start(struct audio_stream *stream)112{113 if (!stream->buffer)114 return;115 116 init_dma(stream->dma);117 if (get_dma_active_buffer(stream->dma) == 0) {118 clear_dma_done0(stream->dma);119 set_dma_addr0(stream->dma, stream->buffer->start);120 set_dma_count0(stream->dma, stream->period_size >> 1);121 set_dma_addr1(stream->dma, stream->buffer->next->start);122 set_dma_count1(stream->dma, stream->period_size >> 1);123 } else {124 clear_dma_done1(stream->dma);125 set_dma_addr1(stream->dma, stream->buffer->start);126 set_dma_count1(stream->dma, stream->period_size >> 1);127 set_dma_addr0(stream->dma, stream->buffer->next->start);128 set_dma_count0(stream->dma, stream->period_size >> 1);129 }130 enable_dma_buffers(stream->dma);131 start_dma(stream->dma);132}133 134static irqreturn_t au1000_dma_interrupt(int irq, void *ptr)135{136 struct audio_stream *stream = (struct audio_stream *)ptr;137 struct snd_pcm_substream *substream = stream->substream;138 139 switch (get_dma_buffer_done(stream->dma)) {140 case DMA_D0:141 stream->buffer = stream->buffer->next;142 clear_dma_done0(stream->dma);143 set_dma_addr0(stream->dma, stream->buffer->next->start);144 set_dma_count0(stream->dma, stream->period_size >> 1);145 enable_dma_buffer0(stream->dma);146 break;147 case DMA_D1:148 stream->buffer = stream->buffer->next;149 clear_dma_done1(stream->dma);150 set_dma_addr1(stream->dma, stream->buffer->next->start);151 set_dma_count1(stream->dma, stream->period_size >> 1);152 enable_dma_buffer1(stream->dma);153 break;154 case (DMA_D0 | DMA_D1):155 pr_debug("DMA %d missed interrupt.\n", stream->dma);156 au1000_dma_stop(stream);157 au1000_dma_start(stream);158 break;159 case (~DMA_D0 & ~DMA_D1):160 pr_debug("DMA %d empty irq.\n", stream->dma);161 }162 snd_pcm_period_elapsed(substream);163 return IRQ_HANDLED;164}165 166static const struct snd_pcm_hardware alchemy_pcm_hardware = {167 .info = SNDRV_PCM_INFO_MMAP | SNDRV_PCM_INFO_MMAP_VALID |168 SNDRV_PCM_INFO_INTERLEAVED | SNDRV_PCM_INFO_BATCH,169 .period_bytes_min = 1024,170 .period_bytes_max = 16 * 1024 - 1,171 .periods_min = 4,172 .periods_max = 255,173 .buffer_bytes_max = 128 * 1024,174 .fifo_size = 16,175};176 177static inline struct alchemy_pcm_ctx *ss_to_ctx(struct snd_pcm_substream *ss,178 struct snd_soc_component *component)179{180 return snd_soc_component_get_drvdata(component);181}182 183static inline struct audio_stream *ss_to_as(struct snd_pcm_substream *ss,184 struct snd_soc_component *component)185{186 struct alchemy_pcm_ctx *ctx = ss_to_ctx(ss, component);187 return &(ctx->stream[ss->stream]);188}189 190static int alchemy_pcm_open(struct snd_soc_component *component,191 struct snd_pcm_substream *substream)192{193 struct alchemy_pcm_ctx *ctx = ss_to_ctx(substream, component);194 struct snd_soc_pcm_runtime *rtd = snd_soc_substream_to_rtd(substream);195 int *dmaids, s = substream->stream;196 char *name;197 198 dmaids = snd_soc_dai_get_dma_data(snd_soc_rtd_to_cpu(rtd, 0), substream);199 if (!dmaids)200 return -ENODEV; /* whoa, has ordering changed? */201 202 /* DMA setup */203 name = (s == SNDRV_PCM_STREAM_PLAYBACK) ? "audio-tx" : "audio-rx";204 ctx->stream[s].dma = request_au1000_dma(dmaids[s], name,205 au1000_dma_interrupt, 0,206 &ctx->stream[s]);207 set_dma_mode(ctx->stream[s].dma,208 get_dma_mode(ctx->stream[s].dma) & ~DMA_NC);209 210 ctx->stream[s].substream = substream;211 ctx->stream[s].buffer = NULL;212 snd_soc_set_runtime_hwparams(substream, &alchemy_pcm_hardware);213 214 return 0;215}216 217static int alchemy_pcm_close(struct snd_soc_component *component,218 struct snd_pcm_substream *substream)219{220 struct alchemy_pcm_ctx *ctx = ss_to_ctx(substream, component);221 int stype = substream->stream;222 223 ctx->stream[stype].substream = NULL;224 free_au1000_dma(ctx->stream[stype].dma);225 226 return 0;227}228 229static int alchemy_pcm_hw_params(struct snd_soc_component *component,230 struct snd_pcm_substream *substream,231 struct snd_pcm_hw_params *hw_params)232{233 struct audio_stream *stream = ss_to_as(substream, component);234 235 return au1000_setup_dma_link(stream,236 params_period_bytes(hw_params),237 params_periods(hw_params));238}239 240static int alchemy_pcm_hw_free(struct snd_soc_component *component,241 struct snd_pcm_substream *substream)242{243 struct audio_stream *stream = ss_to_as(substream, component);244 au1000_release_dma_link(stream);245 return 0;246}247 248static int alchemy_pcm_trigger(struct snd_soc_component *component,249 struct snd_pcm_substream *substream, int cmd)250{251 struct audio_stream *stream = ss_to_as(substream, component);252 int err = 0;253 254 switch (cmd) {255 case SNDRV_PCM_TRIGGER_START:256 au1000_dma_start(stream);257 break;258 case SNDRV_PCM_TRIGGER_STOP:259 au1000_dma_stop(stream);260 break;261 default:262 err = -EINVAL;263 break;264 }265 return err;266}267 268static snd_pcm_uframes_t alchemy_pcm_pointer(struct snd_soc_component *component,269 struct snd_pcm_substream *ss)270{271 struct audio_stream *stream = ss_to_as(ss, component);272 long location;273 274 location = get_dma_residue(stream->dma);275 location = stream->buffer->relative_end - location;276 if (location == -1)277 location = 0;278 return bytes_to_frames(ss->runtime, location);279}280 281static int alchemy_pcm_new(struct snd_soc_component *component,282 struct snd_soc_pcm_runtime *rtd)283{284 struct snd_pcm *pcm = rtd->pcm;285 286 snd_pcm_set_managed_buffer_all(pcm, SNDRV_DMA_TYPE_CONTINUOUS,287 NULL, 65536, (4096 * 1024) - 1);288 289 return 0;290}291 292static struct snd_soc_component_driver alchemy_pcm_soc_component = {293 .name = DRV_NAME,294 .open = alchemy_pcm_open,295 .close = alchemy_pcm_close,296 .hw_params = alchemy_pcm_hw_params,297 .hw_free = alchemy_pcm_hw_free,298 .trigger = alchemy_pcm_trigger,299 .pointer = alchemy_pcm_pointer,300 .pcm_construct = alchemy_pcm_new,301};302 303static int alchemy_pcm_drvprobe(struct platform_device *pdev)304{305 struct alchemy_pcm_ctx *ctx;306 307 ctx = devm_kzalloc(&pdev->dev, sizeof(*ctx), GFP_KERNEL);308 if (!ctx)309 return -ENOMEM;310 311 platform_set_drvdata(pdev, ctx);312 313 return devm_snd_soc_register_component(&pdev->dev,314 &alchemy_pcm_soc_component, NULL, 0);315}316 317static struct platform_driver alchemy_pcmdma_driver = {318 .driver = {319 .name = "alchemy-pcm-dma",320 },321 .probe = alchemy_pcm_drvprobe,322};323 324module_platform_driver(alchemy_pcmdma_driver);325 326MODULE_LICENSE("GPL");327MODULE_DESCRIPTION("Au1000/Au1500/Au1100 Audio DMA driver");328MODULE_AUTHOR("Manuel Lauss");329