sound/soc/davinci/davinci-pcm.c

   1 /*
   2  * ALSA PCM interface for the TI DAVINCI processor
   3  *
   4  * Author:      Vladimir Barinov, <vbarinov@embeddedalley.com>
   5  * Copyright:   (C) 2007 MontaVista Software, Inc., <source@mvista.com>
   6  * added SRAM ping/pong (C) 2008 Troy Kisky <troy.kisky@boundarydevices.com>
   7  *
   8  * This program is free software; you can redistribute it and/or modify
   9  * it under the terms of the GNU General Public License version 2 as
  10  * published by the Free Software Foundation.
  11  */
  12
  13 #include <linux/module.h>
  14 #include <linux/init.h>
  15 #include <linux/platform_device.h>
  16 #include <linux/slab.h>
  17 #include <linux/dma-mapping.h>
  18 #include <linux/kernel.h>
  19 #include <linux/genalloc.h>
  20 #include <linux/platform_data/edma.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/dma.h>
  28
  29 #include "davinci-pcm.h"
  30
  31 #ifdef DEBUG
  32 static void print_buf_info(int slot, char *name)
  33 {
  34         struct edmacc_param p;
  35         if (slot < 0)
  36                 return;
  37         edma_read_slot(slot, &p);
  38         printk(KERN_DEBUG "%s: 0x%x, opt=%x, src=%x, a_b_cnt=%x dst=%x\n",
  39                         name, slot, p.opt, p.src, p.a_b_cnt, p.dst);
  40         printk(KERN_DEBUG "    src_dst_bidx=%x link_bcntrld=%x src_dst_cidx=%x ccnt=%x\n",
  41                         p.src_dst_bidx, p.link_bcntrld, p.src_dst_cidx, p.ccnt);
  42 }
  43 #else
  44 static void print_buf_info(int slot, char *name)
  45 {
  46 }
  47 #endif
  48
  49 #define DAVINCI_PCM_FMTBITS     (\
  50                                 SNDRV_PCM_FMTBIT_S8     |\
  51                                 SNDRV_PCM_FMTBIT_U8     |\
  52                                 SNDRV_PCM_FMTBIT_S16_LE |\
  53                                 SNDRV_PCM_FMTBIT_S16_BE |\
  54                                 SNDRV_PCM_FMTBIT_U16_LE |\
  55                                 SNDRV_PCM_FMTBIT_U16_BE |\
  56                                 SNDRV_PCM_FMTBIT_S24_LE |\
  57                                 SNDRV_PCM_FMTBIT_S24_BE |\
  58                                 SNDRV_PCM_FMTBIT_U24_LE |\
  59                                 SNDRV_PCM_FMTBIT_U24_BE |\
  60                                 SNDRV_PCM_FMTBIT_S32_LE |\
  61                                 SNDRV_PCM_FMTBIT_S32_BE |\
  62                                 SNDRV_PCM_FMTBIT_U32_LE |\
  63                                 SNDRV_PCM_FMTBIT_U32_BE)
  64
  65 static struct snd_pcm_hardware pcm_hardware_playback = {
  66         .info = (SNDRV_PCM_INFO_INTERLEAVED | SNDRV_PCM_INFO_BLOCK_TRANSFER |
  67                  SNDRV_PCM_INFO_MMAP | SNDRV_PCM_INFO_MMAP_VALID |
  68                  SNDRV_PCM_INFO_PAUSE | SNDRV_PCM_INFO_RESUME|
  69                  SNDRV_PCM_INFO_BATCH),
  70         .formats = DAVINCI_PCM_FMTBITS,
  71         .rates = SNDRV_PCM_RATE_8000_192000 | SNDRV_PCM_RATE_KNOT,
  72         .rate_min = 8000,
  73         .rate_max = 192000,
  74         .channels_min = 2,
  75         .channels_max = 384,
  76         .buffer_bytes_max = 128 * 1024,
  77         .period_bytes_min = 32,
  78         .period_bytes_max = 8 * 1024,
  79         .periods_min = 16,
  80         .periods_max = 255,
  81         .fifo_size = 0,
  82 };
  83
  84 static struct snd_pcm_hardware pcm_hardware_capture = {
  85         .info = (SNDRV_PCM_INFO_INTERLEAVED | SNDRV_PCM_INFO_BLOCK_TRANSFER |
  86                  SNDRV_PCM_INFO_MMAP | SNDRV_PCM_INFO_MMAP_VALID |
  87                  SNDRV_PCM_INFO_PAUSE |
  88                  SNDRV_PCM_INFO_BATCH),
  89         .formats = DAVINCI_PCM_FMTBITS,
  90         .rates = SNDRV_PCM_RATE_8000_192000 | SNDRV_PCM_RATE_KNOT,
  91         .rate_min = 8000,
  92         .rate_max = 192000,
  93         .channels_min = 2,
  94         .channels_max = 384,
  95         .buffer_bytes_max = 128 * 1024,
  96         .period_bytes_min = 32,
  97         .period_bytes_max = 8 * 1024,
  98         .periods_min = 16,
  99         .periods_max = 255,
 100         .fifo_size = 0,
 101 };
 102
 103 /*
 104  * How ping/pong works....
 105  *
 106  * Playback:
 107  * ram_params - copys 2*ping_size from start of SDRAM to iram,
 108  *      links to ram_link2
 109  * ram_link2 - copys rest of SDRAM to iram in ping_size units,
 110  *      links to ram_link
 111  * ram_link - copys entire SDRAM to iram in ping_size uints,
 112  *      links to self
 113  *
 114  * asp_params - same as asp_link[0]
 115  * asp_link[0] - copys from lower half of iram to asp port
 116  *      links to asp_link[1], triggers iram copy event on completion
 117  * asp_link[1] - copys from upper half of iram to asp port
 118  *      links to asp_link[0], triggers iram copy event on completion
 119  *      triggers interrupt only needed to let upper SOC levels update position
 120  *      in stream on completion
 121  *
 122  * When playback is started:
 123  *      ram_params started
 124  *      asp_params started
 125  *
 126  * Capture:
 127  * ram_params - same as ram_link,
 128  *      links to ram_link
 129  * ram_link - same as playback
 130  *      links to self
 131  *
 132  * asp_params - same as playback
 133  * asp_link[0] - same as playback
 134  * asp_link[1] - same as playback
 135  *
 136  * When capture is started:
 137  *      asp_params started
 138  */
 139 struct davinci_runtime_data {
 140         spinlock_t lock;
 141         int period;             /* current DMA period */
 142         int asp_channel;        /* Master DMA channel */
 143         int asp_link[2];        /* asp parameter link channel, ping/pong */
 144         struct davinci_pcm_dma_params *params;  /* DMA params */
 145         int ram_channel;
 146         int ram_link;
 147         int ram_link2;
 148         struct edmacc_param asp_params;
 149         struct edmacc_param ram_params;
 150 };
 151
 152 static void davinci_pcm_period_elapsed(struct snd_pcm_substream *substream)
 153 {
 154         struct davinci_runtime_data *prtd = substream->runtime->private_data;
 155         struct snd_pcm_runtime *runtime = substream->runtime;
 156
 157         prtd->period++;
 158         if (unlikely(prtd->period >= runtime->periods))
 159                 prtd->period = 0;
 160 }
 161
 162 static void davinci_pcm_period_reset(struct snd_pcm_substream *substream)
 163 {
 164         struct davinci_runtime_data *prtd = substream->runtime->private_data;
 165
 166         prtd->period = 0;
 167 }
 168 /*
 169  * Not used with ping/pong
 170  */
 171 static void davinci_pcm_enqueue_dma(struct snd_pcm_substream *substream)
 172 {
 173         struct davinci_runtime_data *prtd = substream->runtime->private_data;
 174         struct snd_pcm_runtime *runtime = substream->runtime;
 175         unsigned int period_size;
 176         unsigned int dma_offset;
 177         dma_addr_t dma_pos;
 178         dma_addr_t src, dst;
 179         unsigned short src_bidx, dst_bidx;
 180         unsigned short src_cidx, dst_cidx;
 181         unsigned int data_type;
 182         unsigned short acnt;
 183         unsigned int count;
 184         unsigned int fifo_level;
 185
 186         period_size = snd_pcm_lib_period_bytes(substream);
 187         dma_offset = prtd->period * period_size;
 188         dma_pos = runtime->dma_addr + dma_offset;
 189         fifo_level = prtd->params->fifo_level;
 190
 191         pr_debug("davinci_pcm: audio_set_dma_params_play channel = %d "
 192                 "dma_ptr = %x period_size=%x\n", prtd->asp_link[0], dma_pos,
 193                 period_size);
 194
 195         data_type = prtd->params->data_type;
 196         count = period_size / data_type;
 197         if (fifo_level)
 198                 count /= fifo_level;
 199
 200         if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK) {
 201                 src = dma_pos;
 202                 dst = prtd->params->dma_addr;
 203                 src_bidx = data_type;
 204                 dst_bidx = 4;
 205                 src_cidx = data_type * fifo_level;
 206                 dst_cidx = 0;
 207         } else {
 208                 src = prtd->params->dma_addr;
 209                 dst = dma_pos;
 210                 src_bidx = 0;
 211                 dst_bidx = data_type;
 212                 src_cidx = 0;
 213                 dst_cidx = data_type * fifo_level;
 214         }
 215
 216         acnt = prtd->params->acnt;
 217         edma_set_src(prtd->asp_link[0], src, INCR, W8BIT);
 218         edma_set_dest(prtd->asp_link[0], dst, INCR, W8BIT);
 219
 220         edma_set_src_index(prtd->asp_link[0], src_bidx, src_cidx);
 221         edma_set_dest_index(prtd->asp_link[0], dst_bidx, dst_cidx);
 222
 223         if (!fifo_level)
 224                 edma_set_transfer_params(prtd->asp_link[0], acnt, count, 1, 0,
 225                                                         ASYNC);
 226         else
 227                 edma_set_transfer_params(prtd->asp_link[0], acnt,
 228                                                 fifo_level,
 229                                                 count, fifo_level,
 230                                                 ABSYNC);
 231 }
 232
 233 static void davinci_pcm_dma_irq(unsigned link, u16 ch_status, void *data)
 234 {
 235         struct snd_pcm_substream *substream = data;
 236         struct davinci_runtime_data *prtd = substream->runtime->private_data;
 237
 238         print_buf_info(prtd->ram_channel, "i ram_channel");
 239         pr_debug("davinci_pcm: link=%d, status=0x%x\n", link, ch_status);
 240
 241         if (unlikely(ch_status != DMA_COMPLETE))
 242                 return;
 243
 244         if (snd_pcm_running(substream)) {
 245                 spin_lock(&prtd->lock);
 246                 if (prtd->ram_channel < 0) {
 247                         /* No ping/pong must fix up link dma data*/
 248                         davinci_pcm_enqueue_dma(substream);
 249                 }
 250                 davinci_pcm_period_elapsed(substream);
 251                 spin_unlock(&prtd->lock);
 252                 snd_pcm_period_elapsed(substream);
 253         }
 254 }
 255
 256 #ifdef CONFIG_GENERIC_ALLOCATOR
 257 static int allocate_sram(struct snd_pcm_substream *substream,
 258                 struct gen_pool *sram_pool, unsigned size,
 259                 struct snd_pcm_hardware *ppcm)
 260 {
 261         struct snd_dma_buffer *buf = &substream->dma_buffer;
 262         struct snd_dma_buffer *iram_dma = NULL;
 263         dma_addr_t iram_phys = 0;
 264         void *iram_virt = NULL;
 265
 266         if (buf->private_data || !size)
 267                 return 0;
 268
 269         ppcm->period_bytes_max = size;
 270         iram_virt = gen_pool_dma_alloc(sram_pool, size, &iram_phys);
 271         if (!iram_virt)
 272                 goto exit1;
 273         iram_dma = kzalloc(sizeof(*iram_dma), GFP_KERNEL);
 274         if (!iram_dma)
 275                 goto exit2;
 276         iram_dma->area = iram_virt;
 277         iram_dma->addr = iram_phys;
 278         memset(iram_dma->area, 0, size);
 279         iram_dma->bytes = size;
 280         buf->private_data = iram_dma;
 281         return 0;
 282 exit2:
 283         if (iram_virt)
 284                 gen_pool_free(sram_pool, (unsigned)iram_virt, size);
 285 exit1:
 286         return -ENOMEM;
 287 }
 288
 289 static void davinci_free_sram(struct snd_pcm_substream *substream,
 290                               struct snd_dma_buffer *iram_dma)
 291 {
 292         struct davinci_runtime_data *prtd = substream->runtime->private_data;
 293         struct gen_pool *sram_pool = prtd->params->sram_pool;
 294
 295         gen_pool_free(sram_pool, (unsigned) iram_dma->area, iram_dma->bytes);
 296 }
 297 #else
 298 static int allocate_sram(struct snd_pcm_substream *substream,
 299                 struct gen_pool *sram_pool, unsigned size,
 300                 struct snd_pcm_hardware *ppcm)
 301 {
 302         return 0;
 303 }
 304
 305 static void davinci_free_sram(struct snd_pcm_substream *substream,
 306                               struct snd_dma_buffer *iram_dma)
 307 {
 308 }
 309 #endif
 310
 311 /*
 312  * Only used with ping/pong.
 313  * This is called after runtime->dma_addr, period_bytes and data_type are valid
 314  */
 315 static int ping_pong_dma_setup(struct snd_pcm_substream *substream)
 316 {
 317         unsigned short ram_src_cidx, ram_dst_cidx;
 318         struct snd_pcm_runtime *runtime = substream->runtime;
 319         struct davinci_runtime_data *prtd = runtime->private_data;
 320         struct snd_dma_buffer *iram_dma =
 321                 (struct snd_dma_buffer *)substream->dma_buffer.private_data;
 322         struct davinci_pcm_dma_params *params = prtd->params;
 323         unsigned int data_type = params->data_type;
 324         unsigned int acnt = params->acnt;
 325         /* divide by 2 for ping/pong */
 326         unsigned int ping_size = snd_pcm_lib_period_bytes(substream) >> 1;
 327         unsigned int fifo_level = prtd->params->fifo_level;
 328         unsigned int count;
 329         if ((data_type == 0) || (data_type > 4)) {
 330                 printk(KERN_ERR "%s: data_type=%i\n", __func__, data_type);
 331                 return -EINVAL;
 332         }
 333         if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK) {
 334                 dma_addr_t asp_src_pong = iram_dma->addr + ping_size;
 335                 ram_src_cidx = ping_size;
 336                 ram_dst_cidx = -ping_size;
 337                 edma_set_src(prtd->asp_link[1], asp_src_pong, INCR, W8BIT);
 338
 339                 edma_set_src_index(prtd->asp_link[0], data_type,
 340                                 data_type * fifo_level);
 341                 edma_set_src_index(prtd->asp_link[1], data_type,
 342                                 data_type * fifo_level);
 343
 344                 edma_set_src(prtd->ram_link, runtime->dma_addr, INCR, W32BIT);
 345         } else {
 346                 dma_addr_t asp_dst_pong = iram_dma->addr + ping_size;
 347                 ram_src_cidx = -ping_size;
 348                 ram_dst_cidx = ping_size;
 349                 edma_set_dest(prtd->asp_link[1], asp_dst_pong, INCR, W8BIT);
 350
 351                 edma_set_dest_index(prtd->asp_link[0], data_type,
 352                                 data_type * fifo_level);
 353                 edma_set_dest_index(prtd->asp_link[1], data_type,
 354                                 data_type * fifo_level);
 355
 356                 edma_set_dest(prtd->ram_link, runtime->dma_addr, INCR, W32BIT);
 357         }
 358
 359         if (!fifo_level) {
 360                 count = ping_size / data_type;
 361                 edma_set_transfer_params(prtd->asp_link[0], acnt, count,
 362                                 1, 0, ASYNC);
 363                 edma_set_transfer_params(prtd->asp_link[1], acnt, count,
 364                                 1, 0, ASYNC);
 365         } else {
 366                 count = ping_size / (data_type * fifo_level);
 367                 edma_set_transfer_params(prtd->asp_link[0], acnt, fifo_level,
 368                                 count, fifo_level, ABSYNC);
 369                 edma_set_transfer_params(prtd->asp_link[1], acnt, fifo_level,
 370                                 count, fifo_level, ABSYNC);
 371         }
 372
 373         edma_set_src_index(prtd->ram_link, ping_size, ram_src_cidx);
 374         edma_set_dest_index(prtd->ram_link, ping_size, ram_dst_cidx);
 375         edma_set_transfer_params(prtd->ram_link, ping_size, 2,
 376                         runtime->periods, 2, ASYNC);
 377
 378         /* init master params */
 379         edma_read_slot(prtd->asp_link[0], &prtd->asp_params);
 380         edma_read_slot(prtd->ram_link, &prtd->ram_params);
 381         if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK) {
 382                 struct edmacc_param p_ram;
 383                 /* Copy entire iram buffer before playback started */
 384                 prtd->ram_params.a_b_cnt = (1 << 16) | (ping_size << 1);
 385                 /* 0 dst_bidx */
 386                 prtd->ram_params.src_dst_bidx = (ping_size << 1);
 387                 /* 0 dst_cidx */
 388                 prtd->ram_params.src_dst_cidx = (ping_size << 1);
 389                 prtd->ram_params.ccnt = 1;
 390
 391                 /* Skip 1st period */
 392                 edma_read_slot(prtd->ram_link, &p_ram);
 393                 p_ram.src += (ping_size << 1);
 394                 p_ram.ccnt -= 1;
 395                 edma_write_slot(prtd->ram_link2, &p_ram);
 396                 /*
 397                  * When 1st started, ram -> iram dma channel will fill the
 398                  * entire iram.  Then, whenever a ping/pong asp buffer finishes,
 399                  * 1/2 iram will be filled.
 400                  */
 401                 prtd->ram_params.link_bcntrld =
 402                         EDMA_CHAN_SLOT(prtd->ram_link2) << 5;
 403         }
 404         return 0;
 405 }
 406
 407 /* 1 asp tx or rx channel using 2 parameter channels
 408  * 1 ram to/from iram channel using 1 parameter channel
 409  *
 410  * Playback
 411  * ram copy channel kicks off first,
 412  * 1st ram copy of entire iram buffer completion kicks off asp channel
 413  * asp tcc always kicks off ram copy of 1/2 iram buffer
 414  *
 415  * Record
 416  * asp channel starts, tcc kicks off ram copy
 417  */
 418 static int request_ping_pong(struct snd_pcm_substream *substream,
 419                 struct davinci_runtime_data *prtd,
 420                 struct snd_dma_buffer *iram_dma)
 421 {
 422         dma_addr_t asp_src_ping;
 423         dma_addr_t asp_dst_ping;
 424         int ret;
 425         struct davinci_pcm_dma_params *params = prtd->params;
 426
 427         /* Request ram master channel */
 428         ret = prtd->ram_channel = edma_alloc_channel(EDMA_CHANNEL_ANY,
 429                                   davinci_pcm_dma_irq, substream,
 430                                   prtd->params->ram_chan_q);
 431         if (ret < 0)
 432                 goto exit1;
 433
 434         /* Request ram link channel */
 435         ret = prtd->ram_link = edma_alloc_slot(
 436                         EDMA_CTLR(prtd->ram_channel), EDMA_SLOT_ANY);
 437         if (ret < 0)
 438                 goto exit2;
 439
 440         ret = prtd->asp_link[1] = edma_alloc_slot(
 441                         EDMA_CTLR(prtd->asp_channel), EDMA_SLOT_ANY);
 442         if (ret < 0)
 443                 goto exit3;
 444
 445         prtd->ram_link2 = -1;
 446         if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK) {
 447                 ret = prtd->ram_link2 = edma_alloc_slot(
 448                         EDMA_CTLR(prtd->ram_channel), EDMA_SLOT_ANY);
 449                 if (ret < 0)
 450                         goto exit4;
 451         }
 452         /* circle ping-pong buffers */
 453         edma_link(prtd->asp_link[0], prtd->asp_link[1]);
 454         edma_link(prtd->asp_link[1], prtd->asp_link[0]);
 455         /* circle ram buffers */
 456         edma_link(prtd->ram_link, prtd->ram_link);
 457
 458         if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK) {
 459                 asp_src_ping = iram_dma->addr;
 460                 asp_dst_ping = params->dma_addr;        /* fifo */
 461         } else {
 462                 asp_src_ping = params->dma_addr;        /* fifo */
 463                 asp_dst_ping = iram_dma->addr;
 464         }
 465         /* ping */
 466         edma_set_src(prtd->asp_link[0], asp_src_ping, INCR, W16BIT);
 467         edma_set_dest(prtd->asp_link[0], asp_dst_ping, INCR, W16BIT);
 468         edma_set_src_index(prtd->asp_link[0], 0, 0);
 469         edma_set_dest_index(prtd->asp_link[0], 0, 0);
 470
 471         edma_read_slot(prtd->asp_link[0], &prtd->asp_params);
 472         prtd->asp_params.opt &= ~(TCCMODE | EDMA_TCC(0x3f) | TCINTEN);
 473         prtd->asp_params.opt |= TCCHEN |
 474                 EDMA_TCC(prtd->ram_channel & 0x3f);
 475         edma_write_slot(prtd->asp_link[0], &prtd->asp_params);
 476
 477         /* pong */
 478         edma_set_src(prtd->asp_link[1], asp_src_ping, INCR, W16BIT);
 479         edma_set_dest(prtd->asp_link[1], asp_dst_ping, INCR, W16BIT);
 480         edma_set_src_index(prtd->asp_link[1], 0, 0);
 481         edma_set_dest_index(prtd->asp_link[1], 0, 0);
 482
 483         edma_read_slot(prtd->asp_link[1], &prtd->asp_params);
 484         prtd->asp_params.opt &= ~(TCCMODE | EDMA_TCC(0x3f));
 485         /* interrupt after every pong completion */
 486         prtd->asp_params.opt |= TCINTEN | TCCHEN |
 487                 EDMA_TCC(prtd->ram_channel & 0x3f);
 488         edma_write_slot(prtd->asp_link[1], &prtd->asp_params);
 489
 490         /* ram */
 491         edma_set_src(prtd->ram_link, iram_dma->addr, INCR, W32BIT);
 492         edma_set_dest(prtd->ram_link, iram_dma->addr, INCR, W32BIT);
 493         pr_debug("%s: audio dma channels/slots in use for ram:%u %u %u,"
 494                 "for asp:%u %u %u\n", __func__,
 495                 prtd->ram_channel, prtd->ram_link, prtd->ram_link2,
 496                 prtd->asp_channel, prtd->asp_link[0],
 497                 prtd->asp_link[1]);
 498         return 0;
 499 exit4:
 500         edma_free_channel(prtd->asp_link[1]);
 501         prtd->asp_link[1] = -1;
 502 exit3:
 503         edma_free_channel(prtd->ram_link);
 504         prtd->ram_link = -1;
 505 exit2:
 506         edma_free_channel(prtd->ram_channel);
 507         prtd->ram_channel = -1;
 508 exit1:
 509         return ret;
 510 }
 511
 512 static int davinci_pcm_dma_request(struct snd_pcm_substream *substream)
 513 {
 514         struct snd_dma_buffer *iram_dma;
 515         struct davinci_runtime_data *prtd = substream->runtime->private_data;
 516         struct davinci_pcm_dma_params *params = prtd->params;
 517         int ret;
 518
 519         if (!params)
 520                 return -ENODEV;
 521
 522         /* Request asp master DMA channel */
 523         ret = prtd->asp_channel = edma_alloc_channel(params->channel,
 524                         davinci_pcm_dma_irq, substream,
 525                         prtd->params->asp_chan_q);
 526         if (ret < 0)
 527                 goto exit1;
 528
 529         /* Request asp link channels */
 530         ret = prtd->asp_link[0] = edma_alloc_slot(
 531                         EDMA_CTLR(prtd->asp_channel), EDMA_SLOT_ANY);
 532         if (ret < 0)
 533                 goto exit2;
 534
 535         iram_dma = (struct snd_dma_buffer *)substream->dma_buffer.private_data;
 536         if (iram_dma) {
 537                 if (request_ping_pong(substream, prtd, iram_dma) == 0)
 538                         return 0;
 539                 printk(KERN_WARNING "%s: dma channel allocation failed,"
 540                                 "not using sram\n", __func__);
 541         }
 542
 543         /* Issue transfer completion IRQ when the channel completes a
 544          * transfer, then always reload from the same slot (by a kind
 545          * of loopback link).  The completion IRQ handler will update
 546          * the reload slot with a new buffer.
 547          *
 548          * REVISIT save p_ram here after setting up everything except
 549          * the buffer and its length (ccnt) ... use it as a template
 550          * so davinci_pcm_enqueue_dma() takes less time in IRQ.
 551          */
 552         edma_read_slot(prtd->asp_link[0], &prtd->asp_params);
 553         prtd->asp_params.opt |= TCINTEN |
 554                 EDMA_TCC(EDMA_CHAN_SLOT(prtd->asp_channel));
 555         prtd->asp_params.link_bcntrld = EDMA_CHAN_SLOT(prtd->asp_link[0]) << 5;
 556         edma_write_slot(prtd->asp_link[0], &prtd->asp_params);
 557         return 0;
 558 exit2:
 559         edma_free_channel(prtd->asp_channel);
 560         prtd->asp_channel = -1;
 561 exit1:
 562         return ret;
 563 }
 564
 565 static int davinci_pcm_trigger(struct snd_pcm_substream *substream, int cmd)
 566 {
 567         struct davinci_runtime_data *prtd = substream->runtime->private_data;
 568         int ret = 0;
 569
 570         spin_lock(&prtd->lock);
 571
 572         switch (cmd) {
 573         case SNDRV_PCM_TRIGGER_START:
 574                 edma_start(prtd->asp_channel);
 575                 if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK &&
 576                     prtd->ram_channel >= 0) {
 577                         /* copy 1st iram buffer */
 578                         edma_start(prtd->ram_channel);
 579                 }
 580                 break;
 581         case SNDRV_PCM_TRIGGER_RESUME:
 582         case SNDRV_PCM_TRIGGER_PAUSE_RELEASE:
 583                 edma_resume(prtd->asp_channel);
 584                 break;
 585         case SNDRV_PCM_TRIGGER_STOP:
 586         case SNDRV_PCM_TRIGGER_SUSPEND:
 587         case SNDRV_PCM_TRIGGER_PAUSE_PUSH:
 588                 edma_pause(prtd->asp_channel);
 589                 break;
 590         default:
 591                 ret = -EINVAL;
 592                 break;
 593         }
 594
 595         spin_unlock(&prtd->lock);
 596
 597         return ret;
 598 }
 599
 600 static int davinci_pcm_prepare(struct snd_pcm_substream *substream)
 601 {
 602         struct davinci_runtime_data *prtd = substream->runtime->private_data;
 603
 604         davinci_pcm_period_reset(substream);
 605         if (prtd->ram_channel >= 0) {
 606                 int ret = ping_pong_dma_setup(substream);
 607                 if (ret < 0)
 608                         return ret;
 609
 610                 edma_write_slot(prtd->ram_channel, &prtd->ram_params);
 611                 edma_write_slot(prtd->asp_channel, &prtd->asp_params);
 612
 613                 print_buf_info(prtd->ram_channel, "ram_channel");
 614                 print_buf_info(prtd->ram_link, "ram_link");
 615                 print_buf_info(prtd->ram_link2, "ram_link2");
 616                 print_buf_info(prtd->asp_channel, "asp_channel");
 617                 print_buf_info(prtd->asp_link[0], "asp_link[0]");
 618                 print_buf_info(prtd->asp_link[1], "asp_link[1]");
 619
 620                 /*
 621                  * There is a phase offset of 2 periods between the position
 622                  * used by dma setup and the position reported in the pointer
 623                  * function.
 624                  *
 625                  * The phase offset, when not using ping-pong buffers, is due to
 626                  * the two consecutive calls to davinci_pcm_enqueue_dma() below.
 627                  *
 628                  * Whereas here, with ping-pong buffers, the phase is due to
 629                  * there being an entire buffer transfer complete before the
 630                  * first dma completion event triggers davinci_pcm_dma_irq().
 631                  */
 632                 davinci_pcm_period_elapsed(substream);
 633                 davinci_pcm_period_elapsed(substream);
 634
 635                 return 0;
 636         }
 637         davinci_pcm_enqueue_dma(substream);
 638         davinci_pcm_period_elapsed(substream);
 639
 640         /* Copy self-linked parameter RAM entry into master channel */
 641         edma_read_slot(prtd->asp_link[0], &prtd->asp_params);
 642         edma_write_slot(prtd->asp_channel, &prtd->asp_params);
 643         davinci_pcm_enqueue_dma(substream);
 644         davinci_pcm_period_elapsed(substream);
 645
 646         return 0;
 647 }
 648
 649 static snd_pcm_uframes_t
 650 davinci_pcm_pointer(struct snd_pcm_substream *substream)
 651 {
 652         struct snd_pcm_runtime *runtime = substream->runtime;
 653         struct davinci_runtime_data *prtd = runtime->private_data;
 654         unsigned int offset;
 655         int asp_count;
 656         unsigned int period_size = snd_pcm_lib_period_bytes(substream);
 657
 658         /*
 659          * There is a phase offset of 2 periods between the position used by dma
 660          * setup and the position reported in the pointer function. Either +2 in
 661          * the dma setup or -2 here in the pointer function (with wrapping,
 662          * both) accounts for this offset -- choose the latter since it makes
 663          * the first-time setup clearer.
 664          */
 665         spin_lock(&prtd->lock);
 666         asp_count = prtd->period - 2;
 667         spin_unlock(&prtd->lock);
 668
 669         if (asp_count < 0)
 670                 asp_count += runtime->periods;
 671         asp_count *= period_size;
 672
 673         offset = bytes_to_frames(runtime, asp_count);
 674         if (offset >= runtime->buffer_size)
 675                 offset = 0;
 676
 677         return offset;
 678 }
 679
 680 static int davinci_pcm_open(struct snd_pcm_substream *substream)
 681 {
 682         struct snd_pcm_runtime *runtime = substream->runtime;
 683         struct davinci_runtime_data *prtd;
 684         struct snd_pcm_hardware *ppcm;
 685         int ret = 0;
 686         struct snd_soc_pcm_runtime *rtd = substream->private_data;
 687         struct davinci_pcm_dma_params *pa;
 688         struct davinci_pcm_dma_params *params;
 689
 690         pa = snd_soc_dai_get_dma_data(rtd->cpu_dai, substream);
 691         if (!pa)
 692                 return -ENODEV;
 693         params = &pa[substream->stream];
 694
 695         ppcm = (substream->stream == SNDRV_PCM_STREAM_PLAYBACK) ?
 696                         &pcm_hardware_playback : &pcm_hardware_capture;
 697         allocate_sram(substream, params->sram_pool, params->sram_size, ppcm);
 698         snd_soc_set_runtime_hwparams(substream, ppcm);
 699         /* ensure that buffer size is a multiple of period size */
 700         ret = snd_pcm_hw_constraint_integer(runtime,
 701                                                 SNDRV_PCM_HW_PARAM_PERIODS);
 702         if (ret < 0)
 703                 return ret;
 704
 705         prtd = kzalloc(sizeof(struct davinci_runtime_data), GFP_KERNEL);
 706         if (prtd == NULL)
 707                 return -ENOMEM;
 708
 709         spin_lock_init(&prtd->lock);
 710         prtd->params = params;
 711         prtd->asp_channel = -1;
 712         prtd->asp_link[0] = prtd->asp_link[1] = -1;
 713         prtd->ram_channel = -1;
 714         prtd->ram_link = -1;
 715         prtd->ram_link2 = -1;
 716
 717         runtime->private_data = prtd;
 718
 719         ret = davinci_pcm_dma_request(substream);
 720         if (ret) {
 721                 printk(KERN_ERR "davinci_pcm: Failed to get dma channels\n");
 722                 kfree(prtd);
 723         }
 724
 725         return ret;
 726 }
 727
 728 static int davinci_pcm_close(struct snd_pcm_substream *substream)
 729 {
 730         struct snd_pcm_runtime *runtime = substream->runtime;
 731         struct davinci_runtime_data *prtd = runtime->private_data;
 732
 733         if (prtd->ram_channel >= 0)
 734                 edma_stop(prtd->ram_channel);
 735         if (prtd->asp_channel >= 0)
 736                 edma_stop(prtd->asp_channel);
 737         if (prtd->asp_link[0] >= 0)
 738                 edma_unlink(prtd->asp_link[0]);
 739         if (prtd->asp_link[1] >= 0)
 740                 edma_unlink(prtd->asp_link[1]);
 741         if (prtd->ram_link >= 0)
 742                 edma_unlink(prtd->ram_link);
 743
 744         if (prtd->asp_link[0] >= 0)
 745                 edma_free_slot(prtd->asp_link[0]);
 746         if (prtd->asp_link[1] >= 0)
 747                 edma_free_slot(prtd->asp_link[1]);
 748         if (prtd->asp_channel >= 0)
 749                 edma_free_channel(prtd->asp_channel);
 750         if (prtd->ram_link >= 0)
 751                 edma_free_slot(prtd->ram_link);
 752         if (prtd->ram_link2 >= 0)
 753                 edma_free_slot(prtd->ram_link2);
 754         if (prtd->ram_channel >= 0)
 755                 edma_free_channel(prtd->ram_channel);
 756
 757         kfree(prtd);
 758
 759         return 0;
 760 }
 761
 762 static int davinci_pcm_hw_params(struct snd_pcm_substream *substream,
 763                                  struct snd_pcm_hw_params *hw_params)
 764 {
 765         return snd_pcm_lib_malloc_pages(substream,
 766                                         params_buffer_bytes(hw_params));
 767 }
 768
 769 static int davinci_pcm_hw_free(struct snd_pcm_substream *substream)
 770 {
 771         return snd_pcm_lib_free_pages(substream);
 772 }
 773
 774 static int davinci_pcm_mmap(struct snd_pcm_substream *substream,
 775                             struct vm_area_struct *vma)
 776 {
 777         struct snd_pcm_runtime *runtime = substream->runtime;
 778
 779         return dma_mmap_writecombine(substream->pcm->card->dev, vma,
 780                                      runtime->dma_area,
 781                                      runtime->dma_addr,
 782                                      runtime->dma_bytes);
 783 }
 784
 785 static struct snd_pcm_ops davinci_pcm_ops = {
 786         .open =         davinci_pcm_open,
 787         .close =        davinci_pcm_close,
 788         .ioctl =        snd_pcm_lib_ioctl,
 789         .hw_params =    davinci_pcm_hw_params,
 790         .hw_free =      davinci_pcm_hw_free,
 791         .prepare =      davinci_pcm_prepare,
 792         .trigger =      davinci_pcm_trigger,
 793         .pointer =      davinci_pcm_pointer,
 794         .mmap =         davinci_pcm_mmap,
 795 };
 796
 797 static int davinci_pcm_preallocate_dma_buffer(struct snd_pcm *pcm, int stream,
 798                 size_t size)
 799 {
 800         struct snd_pcm_substream *substream = pcm->streams[stream].substream;
 801         struct snd_dma_buffer *buf = &substream->dma_buffer;
 802
 803         buf->dev.type = SNDRV_DMA_TYPE_DEV;
 804         buf->dev.dev = pcm->card->dev;
 805         buf->private_data = NULL;
 806         buf->area = dma_alloc_writecombine(pcm->card->dev, size,
 807                                            &buf->addr, GFP_KERNEL);
 808
 809         pr_debug("davinci_pcm: preallocate_dma_buffer: area=%p, addr=%p, "
 810                 "size=%d\n", (void *) buf->area, (void *) buf->addr, size);
 811
 812         if (!buf->area)
 813                 return -ENOMEM;
 814
 815         buf->bytes = size;
 816         return 0;
 817 }
 818
 819 static void davinci_pcm_free(struct snd_pcm *pcm)
 820 {
 821         struct snd_pcm_substream *substream;
 822         struct snd_dma_buffer *buf;
 823         int stream;
 824
 825         for (stream = 0; stream < 2; stream++) {
 826                 struct snd_dma_buffer *iram_dma;
 827                 substream = pcm->streams[stream].substream;
 828                 if (!substream)
 829                         continue;
 830
 831                 buf = &substream->dma_buffer;
 832                 if (!buf->area)
 833                         continue;
 834
 835                 dma_free_writecombine(pcm->card->dev, buf->bytes,
 836                                       buf->area, buf->addr);
 837                 buf->area = NULL;
 838                 iram_dma = buf->private_data;
 839                 if (iram_dma) {
 840                         davinci_free_sram(substream, iram_dma);
 841                         kfree(iram_dma);
 842                 }
 843         }
 844 }
 845
 846 static int davinci_pcm_new(struct snd_soc_pcm_runtime *rtd)
 847 {
 848         struct snd_card *card = rtd->card->snd_card;
 849         struct snd_pcm *pcm = rtd->pcm;
 850         int ret;
 851
 852         ret = dma_coerce_mask_and_coherent(card->dev, DMA_BIT_MASK(32));
 853         if (ret)
 854                 return ret;
 855
 856         if (pcm->streams[SNDRV_PCM_STREAM_PLAYBACK].substream) {
 857                 ret = davinci_pcm_preallocate_dma_buffer(pcm,
 858                         SNDRV_PCM_STREAM_PLAYBACK,
 859                         pcm_hardware_playback.buffer_bytes_max);
 860                 if (ret)
 861                         return ret;
 862         }
 863
 864         if (pcm->streams[SNDRV_PCM_STREAM_CAPTURE].substream) {
 865                 ret = davinci_pcm_preallocate_dma_buffer(pcm,
 866                         SNDRV_PCM_STREAM_CAPTURE,
 867                         pcm_hardware_capture.buffer_bytes_max);
 868                 if (ret)
 869                         return ret;
 870         }
 871
 872         return 0;
 873 }
 874
 875 static struct snd_soc_platform_driver davinci_soc_platform = {
 876         .ops =          &davinci_pcm_ops,
 877         .pcm_new =      davinci_pcm_new,
 878         .pcm_free =     davinci_pcm_free,
 879 };
 880
 881 int davinci_soc_platform_register(struct device *dev)
 882 {
 883         return snd_soc_register_platform(dev, &davinci_soc_platform);
 884 }
 885 EXPORT_SYMBOL_GPL(davinci_soc_platform_register);
 886
 887 void davinci_soc_platform_unregister(struct device *dev)
 888 {
 889         snd_soc_unregister_platform(dev);
 890 }
 891 EXPORT_SYMBOL_GPL(davinci_soc_platform_unregister);
 892
 893 MODULE_AUTHOR("Vladimir Barinov");
 894 MODULE_DESCRIPTION("TI DAVINCI PCM DMA module");
 895 MODULE_LICENSE("GPL");