1 /* 2 * Au12x0/Au1550 PSC ALSA ASoC audio support. 3 * 4 * (c) 2007-2008 MSC Vertriebsges.m.b.H., 5 * Manuel Lauss <manuel.lauss@gmail.com> 6 * 7 * This program is free software; you can redistribute it and/or modify 8 * it under the terms of the GNU General Public License version 2 as 9 * published by the Free Software Foundation. 10 * 11 * DMA glue for Au1x-PSC audio. 12 * 13 */ 14 15 16 #include <linux/module.h> 17 #include <linux/init.h> 18 #include <linux/platform_device.h> 19 #include <linux/slab.h> 20 #include <linux/dma-mapping.h> 21 22 #include <sound/core.h> 23 #include <sound/pcm.h> 24 #include <sound/pcm_params.h> 25 #include <sound/soc.h> 26 27 #include <asm/mach-au1x00/au1000.h> 28 #include <asm/mach-au1x00/au1xxx_dbdma.h> 29 #include <asm/mach-au1x00/au1xxx_psc.h> 30 31 #include "psc.h" 32 33 /*#define PCM_DEBUG*/ 34 35 #define MSG(x...) printk(KERN_INFO "au1xpsc_pcm: " x) 36 #ifdef PCM_DEBUG 37 #define DBG MSG 38 #else 39 #define DBG(x...) do {} while (0) 40 #endif 41 42 struct au1xpsc_audio_dmadata { 43 /* DDMA control data */ 44 unsigned int ddma_id; /* DDMA direction ID for this PSC */ 45 u32 ddma_chan; /* DDMA context */ 46 47 /* PCM context (for irq handlers) */ 48 struct snd_pcm_substream *substream; 49 unsigned long curr_period; /* current segment DDMA is working on */ 50 unsigned long q_period; /* queue period(s) */ 51 dma_addr_t dma_area; /* address of queued DMA area */ 52 dma_addr_t dma_area_s; /* start address of DMA area */ 53 unsigned long pos; /* current byte position being played */ 54 unsigned long periods; /* number of SG segments in total */ 55 unsigned long period_bytes; /* size in bytes of one SG segment */ 56 57 /* runtime data */ 58 int msbits; 59 }; 60 61 /* 62 * These settings are somewhat okay, at least on my machine audio plays 63 * almost skip-free. Especially the 64kB buffer seems to help a LOT. 64 */ 65 #define AU1XPSC_PERIOD_MIN_BYTES 1024 66 #define AU1XPSC_BUFFER_MIN_BYTES 65536 67 68 /* PCM hardware DMA capabilities - platform specific */ 69 static const struct snd_pcm_hardware au1xpsc_pcm_hardware = { 70 .info = SNDRV_PCM_INFO_MMAP | SNDRV_PCM_INFO_MMAP_VALID | 71 SNDRV_PCM_INFO_INTERLEAVED | SNDRV_PCM_INFO_BATCH, 72 .period_bytes_min = AU1XPSC_PERIOD_MIN_BYTES, 73 .period_bytes_max = 4096 * 1024 - 1, 74 .periods_min = 2, 75 .periods_max = 4096, /* 2 to as-much-as-you-like */ 76 .buffer_bytes_max = 4096 * 1024 - 1, 77 .fifo_size = 16, /* fifo entries of AC97/I2S PSC */ 78 }; 79 80 static void au1x_pcm_queue_tx(struct au1xpsc_audio_dmadata *cd) 81 { 82 au1xxx_dbdma_put_source(cd->ddma_chan, cd->dma_area, 83 cd->period_bytes, DDMA_FLAGS_IE); 84 85 /* update next-to-queue period */ 86 ++cd->q_period; 87 cd->dma_area += cd->period_bytes; 88 if (cd->q_period >= cd->periods) { 89 cd->q_period = 0; 90 cd->dma_area = cd->dma_area_s; 91 } 92 } 93 94 static void au1x_pcm_queue_rx(struct au1xpsc_audio_dmadata *cd) 95 { 96 au1xxx_dbdma_put_dest(cd->ddma_chan, cd->dma_area, 97 cd->period_bytes, DDMA_FLAGS_IE); 98 99 /* update next-to-queue period */ 100 ++cd->q_period; 101 cd->dma_area += cd->period_bytes; 102 if (cd->q_period >= cd->periods) { 103 cd->q_period = 0; 104 cd->dma_area = cd->dma_area_s; 105 } 106 } 107 108 static void au1x_pcm_dmatx_cb(int irq, void *dev_id) 109 { 110 struct au1xpsc_audio_dmadata *cd = dev_id; 111 112 cd->pos += cd->period_bytes; 113 if (++cd->curr_period >= cd->periods) { 114 cd->pos = 0; 115 cd->curr_period = 0; 116 } 117 snd_pcm_period_elapsed(cd->substream); 118 au1x_pcm_queue_tx(cd); 119 } 120 121 static void au1x_pcm_dmarx_cb(int irq, void *dev_id) 122 { 123 struct au1xpsc_audio_dmadata *cd = dev_id; 124 125 cd->pos += cd->period_bytes; 126 if (++cd->curr_period >= cd->periods) { 127 cd->pos = 0; 128 cd->curr_period = 0; 129 } 130 snd_pcm_period_elapsed(cd->substream); 131 au1x_pcm_queue_rx(cd); 132 } 133 134 static void au1x_pcm_dbdma_free(struct au1xpsc_audio_dmadata *pcd) 135 { 136 if (pcd->ddma_chan) { 137 au1xxx_dbdma_stop(pcd->ddma_chan); 138 au1xxx_dbdma_reset(pcd->ddma_chan); 139 au1xxx_dbdma_chan_free(pcd->ddma_chan); 140 pcd->ddma_chan = 0; 141 pcd->msbits = 0; 142 } 143 } 144 145 /* in case of missing DMA ring or changed TX-source / RX-dest bit widths, 146 * allocate (or reallocate) a 2-descriptor DMA ring with bit depth according 147 * to ALSA-supplied sample depth. This is due to limitations in the dbdma api 148 * (cannot adjust source/dest widths of already allocated descriptor ring). 149 */ 150 static int au1x_pcm_dbdma_realloc(struct au1xpsc_audio_dmadata *pcd, 151 int stype, int msbits) 152 { 153 /* DMA only in 8/16/32 bit widths */ 154 if (msbits == 24) 155 msbits = 32; 156 157 /* check current config: correct bits and descriptors allocated? */ 158 if ((pcd->ddma_chan) && (msbits == pcd->msbits)) 159 goto out; /* all ok! */ 160 161 au1x_pcm_dbdma_free(pcd); 162 163 if (stype == SNDRV_PCM_STREAM_CAPTURE) 164 pcd->ddma_chan = au1xxx_dbdma_chan_alloc(pcd->ddma_id, 165 DSCR_CMD0_ALWAYS, 166 au1x_pcm_dmarx_cb, (void *)pcd); 167 else 168 pcd->ddma_chan = au1xxx_dbdma_chan_alloc(DSCR_CMD0_ALWAYS, 169 pcd->ddma_id, 170 au1x_pcm_dmatx_cb, (void *)pcd); 171 172 if (!pcd->ddma_chan) 173 return -ENOMEM; 174 175 au1xxx_dbdma_set_devwidth(pcd->ddma_chan, msbits); 176 au1xxx_dbdma_ring_alloc(pcd->ddma_chan, 2); 177 178 pcd->msbits = msbits; 179 180 au1xxx_dbdma_stop(pcd->ddma_chan); 181 au1xxx_dbdma_reset(pcd->ddma_chan); 182 183 out: 184 return 0; 185 } 186 187 static inline struct au1xpsc_audio_dmadata *to_dmadata(struct snd_pcm_substream *ss) 188 { 189 struct snd_soc_pcm_runtime *rtd = ss->private_data; 190 struct au1xpsc_audio_dmadata *pcd = 191 snd_soc_platform_get_drvdata(rtd->platform); 192 return &pcd[ss->stream]; 193 } 194 195 static int au1xpsc_pcm_hw_params(struct snd_pcm_substream *substream, 196 struct snd_pcm_hw_params *params) 197 { 198 struct snd_pcm_runtime *runtime = substream->runtime; 199 struct au1xpsc_audio_dmadata *pcd; 200 int stype, ret; 201 202 ret = snd_pcm_lib_malloc_pages(substream, params_buffer_bytes(params)); 203 if (ret < 0) 204 goto out; 205 206 stype = substream->stream; 207 pcd = to_dmadata(substream); 208 209 DBG("runtime->dma_area = 0x%08lx dma_addr_t = 0x%08lx dma_size = %d " 210 "runtime->min_align %d\n", 211 (unsigned long)runtime->dma_area, 212 (unsigned long)runtime->dma_addr, runtime->dma_bytes, 213 runtime->min_align); 214 215 DBG("bits %d frags %d frag_bytes %d is_rx %d\n", params->msbits, 216 params_periods(params), params_period_bytes(params), stype); 217 218 ret = au1x_pcm_dbdma_realloc(pcd, stype, params->msbits); 219 if (ret) { 220 MSG("DDMA channel (re)alloc failed!\n"); 221 goto out; 222 } 223 224 pcd->substream = substream; 225 pcd->period_bytes = params_period_bytes(params); 226 pcd->periods = params_periods(params); 227 pcd->dma_area_s = pcd->dma_area = runtime->dma_addr; 228 pcd->q_period = 0; 229 pcd->curr_period = 0; 230 pcd->pos = 0; 231 232 ret = 0; 233 out: 234 return ret; 235 } 236 237 static int au1xpsc_pcm_hw_free(struct snd_pcm_substream *substream) 238 { 239 snd_pcm_lib_free_pages(substream); 240 return 0; 241 } 242 243 static int au1xpsc_pcm_prepare(struct snd_pcm_substream *substream) 244 { 245 struct au1xpsc_audio_dmadata *pcd = to_dmadata(substream); 246 247 au1xxx_dbdma_reset(pcd->ddma_chan); 248 249 if (substream->stream == SNDRV_PCM_STREAM_CAPTURE) { 250 au1x_pcm_queue_rx(pcd); 251 au1x_pcm_queue_rx(pcd); 252 } else { 253 au1x_pcm_queue_tx(pcd); 254 au1x_pcm_queue_tx(pcd); 255 } 256 257 return 0; 258 } 259 260 static int au1xpsc_pcm_trigger(struct snd_pcm_substream *substream, int cmd) 261 { 262 u32 c = to_dmadata(substream)->ddma_chan; 263 264 switch (cmd) { 265 case SNDRV_PCM_TRIGGER_START: 266 case SNDRV_PCM_TRIGGER_RESUME: 267 au1xxx_dbdma_start(c); 268 break; 269 case SNDRV_PCM_TRIGGER_STOP: 270 case SNDRV_PCM_TRIGGER_SUSPEND: 271 au1xxx_dbdma_stop(c); 272 break; 273 default: 274 return -EINVAL; 275 } 276 return 0; 277 } 278 279 static snd_pcm_uframes_t 280 au1xpsc_pcm_pointer(struct snd_pcm_substream *substream) 281 { 282 return bytes_to_frames(substream->runtime, to_dmadata(substream)->pos); 283 } 284 285 static int au1xpsc_pcm_open(struct snd_pcm_substream *substream) 286 { 287 struct au1xpsc_audio_dmadata *pcd = to_dmadata(substream); 288 struct snd_soc_pcm_runtime *rtd = substream->private_data; 289 int stype = substream->stream, *dmaids; 290 291 dmaids = snd_soc_dai_get_dma_data(rtd->cpu_dai, substream); 292 if (!dmaids) 293 return -ENODEV; /* whoa, has ordering changed? */ 294 295 pcd->ddma_id = dmaids[stype]; 296 297 snd_soc_set_runtime_hwparams(substream, &au1xpsc_pcm_hardware); 298 return 0; 299 } 300 301 static int au1xpsc_pcm_close(struct snd_pcm_substream *substream) 302 { 303 au1x_pcm_dbdma_free(to_dmadata(substream)); 304 return 0; 305 } 306 307 static struct snd_pcm_ops au1xpsc_pcm_ops = { 308 .open = au1xpsc_pcm_open, 309 .close = au1xpsc_pcm_close, 310 .ioctl = snd_pcm_lib_ioctl, 311 .hw_params = au1xpsc_pcm_hw_params, 312 .hw_free = au1xpsc_pcm_hw_free, 313 .prepare = au1xpsc_pcm_prepare, 314 .trigger = au1xpsc_pcm_trigger, 315 .pointer = au1xpsc_pcm_pointer, 316 }; 317 318 static int au1xpsc_pcm_new(struct snd_soc_pcm_runtime *rtd) 319 { 320 struct snd_card *card = rtd->card->snd_card; 321 struct snd_pcm *pcm = rtd->pcm; 322 323 snd_pcm_lib_preallocate_pages_for_all(pcm, SNDRV_DMA_TYPE_DEV, 324 card->dev, AU1XPSC_BUFFER_MIN_BYTES, (4096 * 1024) - 1); 325 326 return 0; 327 } 328 329 /* au1xpsc audio platform */ 330 static struct snd_soc_platform_driver au1xpsc_soc_platform = { 331 .ops = &au1xpsc_pcm_ops, 332 .pcm_new = au1xpsc_pcm_new, 333 }; 334 335 static int au1xpsc_pcm_drvprobe(struct platform_device *pdev) 336 { 337 struct au1xpsc_audio_dmadata *dmadata; 338 339 dmadata = devm_kzalloc(&pdev->dev, 340 2 * sizeof(struct au1xpsc_audio_dmadata), 341 GFP_KERNEL); 342 if (!dmadata) 343 return -ENOMEM; 344 345 platform_set_drvdata(pdev, dmadata); 346 347 return snd_soc_register_platform(&pdev->dev, &au1xpsc_soc_platform); 348 } 349 350 static int au1xpsc_pcm_drvremove(struct platform_device *pdev) 351 { 352 snd_soc_unregister_platform(&pdev->dev); 353 354 return 0; 355 } 356 357 static struct platform_driver au1xpsc_pcm_driver = { 358 .driver = { 359 .name = "au1xpsc-pcm", 360 }, 361 .probe = au1xpsc_pcm_drvprobe, 362 .remove = au1xpsc_pcm_drvremove, 363 }; 364 365 module_platform_driver(au1xpsc_pcm_driver); 366 367 MODULE_LICENSE("GPL"); 368 MODULE_DESCRIPTION("Au12x0/Au1550 PSC Audio DMA driver"); 369 MODULE_AUTHOR("Manuel Lauss"); 370