sound/soc/au1x/dbdma2.c

   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 = %zu "
 210             "runtime->min_align %lu\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 devm_snd_soc_register_platform(&pdev->dev,
 348                                               &au1xpsc_soc_platform);
 349 }
 350
 351 static struct platform_driver au1xpsc_pcm_driver = {
 352         .driver = {
 353                 .name   = "au1xpsc-pcm",
 354         },
 355         .probe          = au1xpsc_pcm_drvprobe,
 356 };
 357
 358 module_platform_driver(au1xpsc_pcm_driver);
 359
 360 MODULE_LICENSE("GPL");
 361 MODULE_DESCRIPTION("Au12x0/Au1550 PSC Audio DMA driver");
 362 MODULE_AUTHOR("Manuel Lauss");