1 // SPDX-License-Identifier: GPL-2.0-only 2 /* 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 by 8 * 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 27 struct pcm_period { 28 u32 start; 29 u32 relative_end; /* relative to start of buffer */ 30 struct pcm_period *next; 31 }; 32 33 struct 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 41 struct alchemy_pcm_ctx { 42 struct audio_stream stream[2]; /* playback & capture */ 43 }; 44 45 static 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 63 static 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 } 104 105 static void au1000_dma_stop(struct audio_stream *stream) 106 { 107 if (stream->buffer) 108 disable_dma(stream->dma); 109 } 110 111 static 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 } 133 134 static 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 } 165 166 static 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 }; 176 177 static inline struct alchemy_pcm_ctx *ss_to_ctx(struct snd_pcm_substream *ss) 178 { 179 struct snd_soc_pcm_runtime *rtd = ss->private_data; 180 struct snd_soc_component *component = snd_soc_rtdcom_lookup(rtd, DRV_NAME); 181 return snd_soc_component_get_drvdata(component); 182 } 183 184 static inline struct audio_stream *ss_to_as(struct snd_pcm_substream *ss) 185 { 186 struct alchemy_pcm_ctx *ctx = ss_to_ctx(ss); 187 return &(ctx->stream[ss->stream]); 188 } 189 190 static int alchemy_pcm_open(struct snd_pcm_substream *substream) 191 { 192 struct alchemy_pcm_ctx *ctx = ss_to_ctx(substream); 193 struct snd_soc_pcm_runtime *rtd = substream->private_data; 194 int *dmaids, s = substream->stream; 195 char *name; 196 197 dmaids = snd_soc_dai_get_dma_data(rtd->cpu_dai, substream); 198 if (!dmaids) 199 return -ENODEV; /* whoa, has ordering changed? */ 200 201 /* DMA setup */ 202 name = (s == SNDRV_PCM_STREAM_PLAYBACK) ? "audio-tx" : "audio-rx"; 203 ctx->stream[s].dma = request_au1000_dma(dmaids[s], name, 204 au1000_dma_interrupt, 0, 205 &ctx->stream[s]); 206 set_dma_mode(ctx->stream[s].dma, 207 get_dma_mode(ctx->stream[s].dma) & ~DMA_NC); 208 209 ctx->stream[s].substream = substream; 210 ctx->stream[s].buffer = NULL; 211 snd_soc_set_runtime_hwparams(substream, &alchemy_pcm_hardware); 212 213 return 0; 214 } 215 216 static int alchemy_pcm_close(struct snd_pcm_substream *substream) 217 { 218 struct alchemy_pcm_ctx *ctx = ss_to_ctx(substream); 219 int stype = substream->stream; 220 221 ctx->stream[stype].substream = NULL; 222 free_au1000_dma(ctx->stream[stype].dma); 223 224 return 0; 225 } 226 227 static int alchemy_pcm_hw_params(struct snd_pcm_substream *substream, 228 struct snd_pcm_hw_params *hw_params) 229 { 230 struct audio_stream *stream = ss_to_as(substream); 231 int err; 232 233 err = snd_pcm_lib_malloc_pages(substream, 234 params_buffer_bytes(hw_params)); 235 if (err < 0) 236 return err; 237 err = au1000_setup_dma_link(stream, 238 params_period_bytes(hw_params), 239 params_periods(hw_params)); 240 if (err) 241 snd_pcm_lib_free_pages(substream); 242 243 return err; 244 } 245 246 static int alchemy_pcm_hw_free(struct snd_pcm_substream *substream) 247 { 248 struct audio_stream *stream = ss_to_as(substream); 249 au1000_release_dma_link(stream); 250 return snd_pcm_lib_free_pages(substream); 251 } 252 253 static int alchemy_pcm_trigger(struct snd_pcm_substream *substream, int cmd) 254 { 255 struct audio_stream *stream = ss_to_as(substream); 256 int err = 0; 257 258 switch (cmd) { 259 case SNDRV_PCM_TRIGGER_START: 260 au1000_dma_start(stream); 261 break; 262 case SNDRV_PCM_TRIGGER_STOP: 263 au1000_dma_stop(stream); 264 break; 265 default: 266 err = -EINVAL; 267 break; 268 } 269 return err; 270 } 271 272 static snd_pcm_uframes_t alchemy_pcm_pointer(struct snd_pcm_substream *ss) 273 { 274 struct audio_stream *stream = ss_to_as(ss); 275 long location; 276 277 location = get_dma_residue(stream->dma); 278 location = stream->buffer->relative_end - location; 279 if (location == -1) 280 location = 0; 281 return bytes_to_frames(ss->runtime, location); 282 } 283 284 static const struct snd_pcm_ops alchemy_pcm_ops = { 285 .open = alchemy_pcm_open, 286 .close = alchemy_pcm_close, 287 .ioctl = snd_pcm_lib_ioctl, 288 .hw_params = alchemy_pcm_hw_params, 289 .hw_free = alchemy_pcm_hw_free, 290 .trigger = alchemy_pcm_trigger, 291 .pointer = alchemy_pcm_pointer, 292 }; 293 294 static int alchemy_pcm_new(struct snd_soc_pcm_runtime *rtd) 295 { 296 struct snd_pcm *pcm = rtd->pcm; 297 298 snd_pcm_lib_preallocate_pages_for_all(pcm, SNDRV_DMA_TYPE_CONTINUOUS, 299 snd_dma_continuous_data(GFP_KERNEL), 65536, (4096 * 1024) - 1); 300 301 return 0; 302 } 303 304 static struct snd_soc_component_driver alchemy_pcm_soc_component = { 305 .name = DRV_NAME, 306 .ops = &alchemy_pcm_ops, 307 .pcm_new = alchemy_pcm_new, 308 }; 309 310 static int alchemy_pcm_drvprobe(struct platform_device *pdev) 311 { 312 struct alchemy_pcm_ctx *ctx; 313 314 ctx = devm_kzalloc(&pdev->dev, sizeof(*ctx), GFP_KERNEL); 315 if (!ctx) 316 return -ENOMEM; 317 318 platform_set_drvdata(pdev, ctx); 319 320 return devm_snd_soc_register_component(&pdev->dev, 321 &alchemy_pcm_soc_component, NULL, 0); 322 } 323 324 static struct platform_driver alchemy_pcmdma_driver = { 325 .driver = { 326 .name = "alchemy-pcm-dma", 327 }, 328 .probe = alchemy_pcm_drvprobe, 329 }; 330 331 module_platform_driver(alchemy_pcmdma_driver); 332 333 MODULE_LICENSE("GPL"); 334 MODULE_DESCRIPTION("Au1000/Au1500/Au1100 Audio DMA driver"); 335 MODULE_AUTHOR("Manuel Lauss"); 336