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 DRV_NAME "dbdma2"
  36
  37 #define MSG(x...)       printk(KERN_INFO "au1xpsc_pcm: " x)
  38 #ifdef PCM_DEBUG
  39 #define DBG             MSG
  40 #else
  41 #define DBG(x...)       do {} while (0)
  42 #endif
  43
  44 struct au1xpsc_audio_dmadata {
  45         /* DDMA control data */
  46         unsigned int ddma_id;           /* DDMA direction ID for this PSC */
  47         u32 ddma_chan;                  /* DDMA context */
  48
  49         /* PCM context (for irq handlers) */
  50         struct snd_pcm_substream *substream;
  51         unsigned long curr_period;      /* current segment DDMA is working on */
  52         unsigned long q_period;         /* queue period(s) */
  53         dma_addr_t dma_area;            /* address of queued DMA area */
  54         dma_addr_t dma_area_s;          /* start address of DMA area */
  55         unsigned long pos;              /* current byte position being played */
  56         unsigned long periods;          /* number of SG segments in total */
  57         unsigned long period_bytes;     /* size in bytes of one SG segment */
  58
  59         /* runtime data */
  60         int msbits;
  61 };
  62
  63 /*
  64  * These settings are somewhat okay, at least on my machine audio plays
  65  * almost skip-free. Especially the 64kB buffer seems to help a LOT.
  66  */
  67 #define AU1XPSC_PERIOD_MIN_BYTES        1024
  68 #define AU1XPSC_BUFFER_MIN_BYTES        65536
  69
  70 /* PCM hardware DMA capabilities - platform specific */
  71 static const struct snd_pcm_hardware au1xpsc_pcm_hardware = {
  72         .info             = SNDRV_PCM_INFO_MMAP | SNDRV_PCM_INFO_MMAP_VALID |
  73                             SNDRV_PCM_INFO_INTERLEAVED | SNDRV_PCM_INFO_BATCH,
  74         .period_bytes_min = AU1XPSC_PERIOD_MIN_BYTES,
  75         .period_bytes_max = 4096 * 1024 - 1,
  76         .periods_min      = 2,
  77         .periods_max      = 4096,       /* 2 to as-much-as-you-like */
  78         .buffer_bytes_max = 4096 * 1024 - 1,
  79         .fifo_size        = 16,         /* fifo entries of AC97/I2S PSC */
  80 };
  81
  82 static void au1x_pcm_queue_tx(struct au1xpsc_audio_dmadata *cd)
  83 {
  84         au1xxx_dbdma_put_source(cd->ddma_chan, cd->dma_area,
  85                                 cd->period_bytes, DDMA_FLAGS_IE);
  86
  87         /* update next-to-queue period */
  88         ++cd->q_period;
  89         cd->dma_area += cd->period_bytes;
  90         if (cd->q_period >= cd->periods) {
  91                 cd->q_period = 0;
  92                 cd->dma_area = cd->dma_area_s;
  93         }
  94 }
  95
  96 static void au1x_pcm_queue_rx(struct au1xpsc_audio_dmadata *cd)
  97 {
  98         au1xxx_dbdma_put_dest(cd->ddma_chan, cd->dma_area,
  99                               cd->period_bytes, DDMA_FLAGS_IE);
 100
 101         /* update next-to-queue period */
 102         ++cd->q_period;
 103         cd->dma_area += cd->period_bytes;
 104         if (cd->q_period >= cd->periods) {
 105                 cd->q_period = 0;
 106                 cd->dma_area = cd->dma_area_s;
 107         }
 108 }
 109
 110 static void au1x_pcm_dmatx_cb(int irq, void *dev_id)
 111 {
 112         struct au1xpsc_audio_dmadata *cd = dev_id;
 113
 114         cd->pos += cd->period_bytes;
 115         if (++cd->curr_period >= cd->periods) {
 116                 cd->pos = 0;
 117                 cd->curr_period = 0;
 118         }
 119         snd_pcm_period_elapsed(cd->substream);
 120         au1x_pcm_queue_tx(cd);
 121 }
 122
 123 static void au1x_pcm_dmarx_cb(int irq, void *dev_id)
 124 {
 125         struct au1xpsc_audio_dmadata *cd = dev_id;
 126
 127         cd->pos += cd->period_bytes;
 128         if (++cd->curr_period >= cd->periods) {
 129                 cd->pos = 0;
 130                 cd->curr_period = 0;
 131         }
 132         snd_pcm_period_elapsed(cd->substream);
 133         au1x_pcm_queue_rx(cd);
 134 }
 135
 136 static void au1x_pcm_dbdma_free(struct au1xpsc_audio_dmadata *pcd)
 137 {
 138         if (pcd->ddma_chan) {
 139                 au1xxx_dbdma_stop(pcd->ddma_chan);
 140                 au1xxx_dbdma_reset(pcd->ddma_chan);
 141                 au1xxx_dbdma_chan_free(pcd->ddma_chan);
 142                 pcd->ddma_chan = 0;
 143                 pcd->msbits = 0;
 144         }
 145 }
 146
 147 /* in case of missing DMA ring or changed TX-source / RX-dest bit widths,
 148  * allocate (or reallocate) a 2-descriptor DMA ring with bit depth according
 149  * to ALSA-supplied sample depth.  This is due to limitations in the dbdma api
 150  * (cannot adjust source/dest widths of already allocated descriptor ring).
 151  */
 152 static int au1x_pcm_dbdma_realloc(struct au1xpsc_audio_dmadata *pcd,
 153                                  int stype, int msbits)
 154 {
 155         /* DMA only in 8/16/32 bit widths */
 156         if (msbits == 24)
 157                 msbits = 32;
 158
 159         /* check current config: correct bits and descriptors allocated? */
 160         if ((pcd->ddma_chan) && (msbits == pcd->msbits))
 161                 goto out;       /* all ok! */
 162
 163         au1x_pcm_dbdma_free(pcd);
 164
 165         if (stype == SNDRV_PCM_STREAM_CAPTURE)
 166                 pcd->ddma_chan = au1xxx_dbdma_chan_alloc(pcd->ddma_id,
 167                                         DSCR_CMD0_ALWAYS,
 168                                         au1x_pcm_dmarx_cb, (void *)pcd);
 169         else
 170                 pcd->ddma_chan = au1xxx_dbdma_chan_alloc(DSCR_CMD0_ALWAYS,
 171                                         pcd->ddma_id,
 172                                         au1x_pcm_dmatx_cb, (void *)pcd);
 173
 174         if (!pcd->ddma_chan)
 175                 return -ENOMEM;
 176
 177         au1xxx_dbdma_set_devwidth(pcd->ddma_chan, msbits);
 178         au1xxx_dbdma_ring_alloc(pcd->ddma_chan, 2);
 179
 180         pcd->msbits = msbits;
 181
 182         au1xxx_dbdma_stop(pcd->ddma_chan);
 183         au1xxx_dbdma_reset(pcd->ddma_chan);
 184
 185 out:
 186         return 0;
 187 }
 188
 189 static inline struct au1xpsc_audio_dmadata *to_dmadata(struct snd_pcm_substream *ss)
 190 {
 191         struct snd_soc_pcm_runtime *rtd = ss->private_data;
 192         struct snd_soc_component *component = snd_soc_rtdcom_lookup(rtd, DRV_NAME);
 193         struct au1xpsc_audio_dmadata *pcd = snd_soc_component_get_drvdata(component);
 194         return &pcd[ss->stream];
 195 }
 196
 197 static int au1xpsc_pcm_hw_params(struct snd_pcm_substream *substream,
 198                                  struct snd_pcm_hw_params *params)
 199 {
 200         struct snd_pcm_runtime *runtime = substream->runtime;
 201         struct au1xpsc_audio_dmadata *pcd;
 202         int stype, ret;
 203
 204         ret = snd_pcm_lib_malloc_pages(substream, params_buffer_bytes(params));
 205         if (ret < 0)
 206                 goto out;
 207
 208         stype = substream->stream;
 209         pcd = to_dmadata(substream);
 210
 211         DBG("runtime->dma_area = 0x%08lx dma_addr_t = 0x%08lx dma_size = %zu "
 212             "runtime->min_align %lu\n",
 213                 (unsigned long)runtime->dma_area,
 214                 (unsigned long)runtime->dma_addr, runtime->dma_bytes,
 215                 runtime->min_align);
 216
 217         DBG("bits %d  frags %d  frag_bytes %d  is_rx %d\n", params->msbits,
 218                 params_periods(params), params_period_bytes(params), stype);
 219
 220         ret = au1x_pcm_dbdma_realloc(pcd, stype, params->msbits);
 221         if (ret) {
 222                 MSG("DDMA channel (re)alloc failed!\n");
 223                 goto out;
 224         }
 225
 226         pcd->substream = substream;
 227         pcd->period_bytes = params_period_bytes(params);
 228         pcd->periods = params_periods(params);
 229         pcd->dma_area_s = pcd->dma_area = runtime->dma_addr;
 230         pcd->q_period = 0;
 231         pcd->curr_period = 0;
 232         pcd->pos = 0;
 233
 234         ret = 0;
 235 out:
 236         return ret;
 237 }
 238
 239 static int au1xpsc_pcm_hw_free(struct snd_pcm_substream *substream)
 240 {
 241         snd_pcm_lib_free_pages(substream);
 242         return 0;
 243 }
 244
 245 static int au1xpsc_pcm_prepare(struct snd_pcm_substream *substream)
 246 {
 247         struct au1xpsc_audio_dmadata *pcd = to_dmadata(substream);
 248
 249         au1xxx_dbdma_reset(pcd->ddma_chan);
 250
 251         if (substream->stream == SNDRV_PCM_STREAM_CAPTURE) {
 252                 au1x_pcm_queue_rx(pcd);
 253                 au1x_pcm_queue_rx(pcd);
 254         } else {
 255                 au1x_pcm_queue_tx(pcd);
 256                 au1x_pcm_queue_tx(pcd);
 257         }
 258
 259         return 0;
 260 }
 261
 262 static int au1xpsc_pcm_trigger(struct snd_pcm_substream *substream, int cmd)
 263 {
 264         u32 c = to_dmadata(substream)->ddma_chan;
 265
 266         switch (cmd) {
 267         case SNDRV_PCM_TRIGGER_START:
 268         case SNDRV_PCM_TRIGGER_RESUME:
 269                 au1xxx_dbdma_start(c);
 270                 break;
 271         case SNDRV_PCM_TRIGGER_STOP:
 272         case SNDRV_PCM_TRIGGER_SUSPEND:
 273                 au1xxx_dbdma_stop(c);
 274                 break;
 275         default:
 276                 return -EINVAL;
 277         }
 278         return 0;
 279 }
 280
 281 static snd_pcm_uframes_t
 282 au1xpsc_pcm_pointer(struct snd_pcm_substream *substream)
 283 {
 284         return bytes_to_frames(substream->runtime, to_dmadata(substream)->pos);
 285 }
 286
 287 static int au1xpsc_pcm_open(struct snd_pcm_substream *substream)
 288 {
 289         struct au1xpsc_audio_dmadata *pcd = to_dmadata(substream);
 290         struct snd_soc_pcm_runtime *rtd = substream->private_data;
 291         int stype = substream->stream, *dmaids;
 292
 293         dmaids = snd_soc_dai_get_dma_data(rtd->cpu_dai, substream);
 294         if (!dmaids)
 295                 return -ENODEV; /* whoa, has ordering changed? */
 296
 297         pcd->ddma_id = dmaids[stype];
 298
 299         snd_soc_set_runtime_hwparams(substream, &au1xpsc_pcm_hardware);
 300         return 0;
 301 }
 302
 303 static int au1xpsc_pcm_close(struct snd_pcm_substream *substream)
 304 {
 305         au1x_pcm_dbdma_free(to_dmadata(substream));
 306         return 0;
 307 }
 308
 309 static const struct snd_pcm_ops au1xpsc_pcm_ops = {
 310         .open           = au1xpsc_pcm_open,
 311         .close          = au1xpsc_pcm_close,
 312         .ioctl          = snd_pcm_lib_ioctl,
 313         .hw_params      = au1xpsc_pcm_hw_params,
 314         .hw_free        = au1xpsc_pcm_hw_free,
 315         .prepare        = au1xpsc_pcm_prepare,
 316         .trigger        = au1xpsc_pcm_trigger,
 317         .pointer        = au1xpsc_pcm_pointer,
 318 };
 319
 320 static int au1xpsc_pcm_new(struct snd_soc_pcm_runtime *rtd)
 321 {
 322         struct snd_card *card = rtd->card->snd_card;
 323         struct snd_pcm *pcm = rtd->pcm;
 324
 325         snd_pcm_lib_preallocate_pages_for_all(pcm, SNDRV_DMA_TYPE_DEV,
 326                 card->dev, AU1XPSC_BUFFER_MIN_BYTES, (4096 * 1024) - 1);
 327
 328         return 0;
 329 }
 330
 331 /* au1xpsc audio platform */
 332 static struct snd_soc_component_driver au1xpsc_soc_component = {
 333         .name           = DRV_NAME,
 334         .ops            = &au1xpsc_pcm_ops,
 335         .pcm_new        = au1xpsc_pcm_new,
 336 };
 337
 338 static int au1xpsc_pcm_drvprobe(struct platform_device *pdev)
 339 {
 340         struct au1xpsc_audio_dmadata *dmadata;
 341
 342         dmadata = devm_kcalloc(&pdev->dev,
 343                                2, sizeof(struct au1xpsc_audio_dmadata),
 344                                GFP_KERNEL);
 345         if (!dmadata)
 346                 return -ENOMEM;
 347
 348         platform_set_drvdata(pdev, dmadata);
 349
 350         return devm_snd_soc_register_component(&pdev->dev,
 351                                         &au1xpsc_soc_component, NULL, 0);
 352 }
 353
 354 static struct platform_driver au1xpsc_pcm_driver = {
 355         .driver = {
 356                 .name   = "au1xpsc-pcm",
 357         },
 358         .probe          = au1xpsc_pcm_drvprobe,
 359 };
 360
 361 module_platform_driver(au1xpsc_pcm_driver);
 362
 363 MODULE_LICENSE("GPL");
 364 MODULE_DESCRIPTION("Au12x0/Au1550 PSC Audio DMA driver");
 365 MODULE_AUTHOR("Manuel Lauss");