sound/soc/samsung/idma.c

   1 /*
   2  * sound/soc/samsung/idma.c
   3  *
   4  * Copyright (c) 2011 Samsung Electronics Co., Ltd.
   5  *              http://www.samsung.com
   6  *
   7  * I2S0's Internal DMA driver
   8  *
   9  * This program is free software; you can redistribute  it and/or modify it
  10  * under  the terms of  the GNU General  Public License as published by the
  11  * Free Software Foundation;  either version 2 of the  License, or (at your
  12  * option) any later version.
  13  */
  14 #include <linux/interrupt.h>
  15 #include <linux/platform_device.h>
  16 #include <linux/dma-mapping.h>
  17 #include <linux/slab.h>
  18 #include <linux/module.h>
  19 #include <sound/pcm.h>
  20 #include <sound/pcm_params.h>
  21 #include <sound/soc.h>
  22
  23 #include "i2s.h"
  24 #include "idma.h"
  25 #include "i2s-regs.h"
  26
  27 #define ST_RUNNING              (1<<0)
  28 #define ST_OPENED               (1<<1)
  29
  30 static const struct snd_pcm_hardware idma_hardware = {
  31         .info = SNDRV_PCM_INFO_INTERLEAVED |
  32                     SNDRV_PCM_INFO_BLOCK_TRANSFER |
  33                     SNDRV_PCM_INFO_MMAP |
  34                     SNDRV_PCM_INFO_MMAP_VALID |
  35                     SNDRV_PCM_INFO_PAUSE |
  36                     SNDRV_PCM_INFO_RESUME,
  37         .buffer_bytes_max = MAX_IDMA_BUFFER,
  38         .period_bytes_min = 128,
  39         .period_bytes_max = MAX_IDMA_PERIOD,
  40         .periods_min = 1,
  41         .periods_max = 2,
  42 };
  43
  44 struct idma_ctrl {
  45         spinlock_t      lock;
  46         int             state;
  47         dma_addr_t      start;
  48         dma_addr_t      pos;
  49         dma_addr_t      end;
  50         dma_addr_t      period;
  51         dma_addr_t      periodsz;
  52         void            *token;
  53         void            (*cb)(void *dt, int bytes_xfer);
  54 };
  55
  56 static struct idma_info {
  57         spinlock_t      lock;
  58         void             __iomem  *regs;
  59         dma_addr_t      lp_tx_addr;
  60 } idma;
  61
  62 static int idma_irq;
  63
  64 static void idma_getpos(dma_addr_t *src)
  65 {
  66         *src = idma.lp_tx_addr +
  67                 (readl(idma.regs + I2STRNCNT) & 0xffffff) * 4;
  68 }
  69
  70 static int idma_enqueue(struct snd_pcm_substream *substream)
  71 {
  72         struct snd_pcm_runtime *runtime = substream->runtime;
  73         struct idma_ctrl *prtd = substream->runtime->private_data;
  74         u32 val;
  75
  76         spin_lock(&prtd->lock);
  77         prtd->token = (void *) substream;
  78         spin_unlock(&prtd->lock);
  79
  80         /* Internal DMA Level0 Interrupt Address */
  81         val = idma.lp_tx_addr + prtd->periodsz;
  82         writel(val, idma.regs + I2SLVL0ADDR);
  83
  84         /* Start address0 of I2S internal DMA operation. */
  85         val = idma.lp_tx_addr;
  86         writel(val, idma.regs + I2SSTR0);
  87
  88         /*
  89          * Transfer block size for I2S internal DMA.
  90          * Should decide transfer size before start dma operation
  91          */
  92         val = readl(idma.regs + I2SSIZE);
  93         val &= ~(I2SSIZE_TRNMSK << I2SSIZE_SHIFT);
  94         val |= (((runtime->dma_bytes >> 2) &
  95                         I2SSIZE_TRNMSK) << I2SSIZE_SHIFT);
  96         writel(val, idma.regs + I2SSIZE);
  97
  98         val = readl(idma.regs + I2SAHB);
  99         val |= AHB_INTENLVL0;
 100         writel(val, idma.regs + I2SAHB);
 101
 102         return 0;
 103 }
 104
 105 static void idma_setcallbk(struct snd_pcm_substream *substream,
 106                                 void (*cb)(void *, int))
 107 {
 108         struct idma_ctrl *prtd = substream->runtime->private_data;
 109
 110         spin_lock(&prtd->lock);
 111         prtd->cb = cb;
 112         spin_unlock(&prtd->lock);
 113 }
 114
 115 static void idma_control(int op)
 116 {
 117         u32 val = readl(idma.regs + I2SAHB);
 118
 119         spin_lock(&idma.lock);
 120
 121         switch (op) {
 122         case LPAM_DMA_START:
 123                 val |= (AHB_INTENLVL0 | AHB_DMAEN);
 124                 break;
 125         case LPAM_DMA_STOP:
 126                 val &= ~(AHB_INTENLVL0 | AHB_DMAEN);
 127                 break;
 128         default:
 129                 spin_unlock(&idma.lock);
 130                 return;
 131         }
 132
 133         writel(val, idma.regs + I2SAHB);
 134         spin_unlock(&idma.lock);
 135 }
 136
 137 static void idma_done(void *id, int bytes_xfer)
 138 {
 139         struct snd_pcm_substream *substream = id;
 140         struct idma_ctrl *prtd = substream->runtime->private_data;
 141
 142         if (prtd && (prtd->state & ST_RUNNING))
 143                 snd_pcm_period_elapsed(substream);
 144 }
 145
 146 static int idma_hw_params(struct snd_pcm_substream *substream,
 147                                 struct snd_pcm_hw_params *params)
 148 {
 149         struct snd_pcm_runtime *runtime = substream->runtime;
 150         struct idma_ctrl *prtd = substream->runtime->private_data;
 151         u32 mod = readl(idma.regs + I2SMOD);
 152         u32 ahb = readl(idma.regs + I2SAHB);
 153
 154         ahb |= (AHB_DMARLD | AHB_INTMASK);
 155         mod |= MOD_TXS_IDMA;
 156         writel(ahb, idma.regs + I2SAHB);
 157         writel(mod, idma.regs + I2SMOD);
 158
 159         snd_pcm_set_runtime_buffer(substream, &substream->dma_buffer);
 160         runtime->dma_bytes = params_buffer_bytes(params);
 161
 162         prtd->start = prtd->pos = runtime->dma_addr;
 163         prtd->period = params_periods(params);
 164         prtd->periodsz = params_period_bytes(params);
 165         prtd->end = runtime->dma_addr + runtime->dma_bytes;
 166
 167         idma_setcallbk(substream, idma_done);
 168
 169         return 0;
 170 }
 171
 172 static int idma_hw_free(struct snd_pcm_substream *substream)
 173 {
 174         snd_pcm_set_runtime_buffer(substream, NULL);
 175
 176         return 0;
 177 }
 178
 179 static int idma_prepare(struct snd_pcm_substream *substream)
 180 {
 181         struct idma_ctrl *prtd = substream->runtime->private_data;
 182
 183         prtd->pos = prtd->start;
 184
 185         /* flush the DMA channel */
 186         idma_control(LPAM_DMA_STOP);
 187         idma_enqueue(substream);
 188
 189         return 0;
 190 }
 191
 192 static int idma_trigger(struct snd_pcm_substream *substream, int cmd)
 193 {
 194         struct idma_ctrl *prtd = substream->runtime->private_data;
 195         int ret = 0;
 196
 197         spin_lock(&prtd->lock);
 198
 199         switch (cmd) {
 200         case SNDRV_PCM_TRIGGER_RESUME:
 201         case SNDRV_PCM_TRIGGER_START:
 202         case SNDRV_PCM_TRIGGER_PAUSE_RELEASE:
 203                 prtd->state |= ST_RUNNING;
 204                 idma_control(LPAM_DMA_START);
 205                 break;
 206
 207         case SNDRV_PCM_TRIGGER_SUSPEND:
 208         case SNDRV_PCM_TRIGGER_STOP:
 209         case SNDRV_PCM_TRIGGER_PAUSE_PUSH:
 210                 prtd->state &= ~ST_RUNNING;
 211                 idma_control(LPAM_DMA_STOP);
 212                 break;
 213
 214         default:
 215                 ret = -EINVAL;
 216                 break;
 217         }
 218
 219         spin_unlock(&prtd->lock);
 220
 221         return ret;
 222 }
 223
 224 static snd_pcm_uframes_t
 225         idma_pointer(struct snd_pcm_substream *substream)
 226 {
 227         struct snd_pcm_runtime *runtime = substream->runtime;
 228         struct idma_ctrl *prtd = runtime->private_data;
 229         dma_addr_t src;
 230         unsigned long res;
 231
 232         spin_lock(&prtd->lock);
 233
 234         idma_getpos(&src);
 235         res = src - prtd->start;
 236
 237         spin_unlock(&prtd->lock);
 238
 239         return bytes_to_frames(substream->runtime, res);
 240 }
 241
 242 static int idma_mmap(struct snd_pcm_substream *substream,
 243         struct vm_area_struct *vma)
 244 {
 245         struct snd_pcm_runtime *runtime = substream->runtime;
 246         unsigned long size, offset;
 247         int ret;
 248
 249         /* From snd_pcm_lib_mmap_iomem */
 250         vma->vm_page_prot = pgprot_noncached(vma->vm_page_prot);
 251         size = vma->vm_end - vma->vm_start;
 252         offset = vma->vm_pgoff << PAGE_SHIFT;
 253         ret = io_remap_pfn_range(vma, vma->vm_start,
 254                         (runtime->dma_addr + offset) >> PAGE_SHIFT,
 255                         size, vma->vm_page_prot);
 256
 257         return ret;
 258 }
 259
 260 static irqreturn_t iis_irq(int irqno, void *dev_id)
 261 {
 262         struct idma_ctrl *prtd = (struct idma_ctrl *)dev_id;
 263         u32 iisahb, val, addr;
 264
 265         iisahb  = readl(idma.regs + I2SAHB);
 266
 267         val = (iisahb & AHB_LVL0INT) ? AHB_CLRLVL0INT : 0;
 268
 269         if (val) {
 270                 iisahb |= val;
 271                 writel(iisahb, idma.regs + I2SAHB);
 272
 273                 addr = readl(idma.regs + I2SLVL0ADDR) - idma.lp_tx_addr;
 274                 addr += prtd->periodsz;
 275                 addr %= (u32)(prtd->end - prtd->start);
 276                 addr += idma.lp_tx_addr;
 277
 278                 writel(addr, idma.regs + I2SLVL0ADDR);
 279
 280                 if (prtd->cb)
 281                         prtd->cb(prtd->token, prtd->period);
 282         }
 283
 284         return IRQ_HANDLED;
 285 }
 286
 287 static int idma_open(struct snd_pcm_substream *substream)
 288 {
 289         struct snd_pcm_runtime *runtime = substream->runtime;
 290         struct idma_ctrl *prtd;
 291         int ret;
 292
 293         snd_soc_set_runtime_hwparams(substream, &idma_hardware);
 294
 295         prtd = kzalloc(sizeof(struct idma_ctrl), GFP_KERNEL);
 296         if (prtd == NULL)
 297                 return -ENOMEM;
 298
 299         ret = request_irq(idma_irq, iis_irq, 0, "i2s", prtd);
 300         if (ret < 0) {
 301                 pr_err("fail to claim i2s irq , ret = %d\n", ret);
 302                 kfree(prtd);
 303                 return ret;
 304         }
 305
 306         spin_lock_init(&prtd->lock);
 307
 308         runtime->private_data = prtd;
 309
 310         return 0;
 311 }
 312
 313 static int idma_close(struct snd_pcm_substream *substream)
 314 {
 315         struct snd_pcm_runtime *runtime = substream->runtime;
 316         struct idma_ctrl *prtd = runtime->private_data;
 317
 318         free_irq(idma_irq, prtd);
 319
 320         if (!prtd)
 321                 pr_err("idma_close called with prtd == NULL\n");
 322
 323         kfree(prtd);
 324
 325         return 0;
 326 }
 327
 328 static const struct snd_pcm_ops idma_ops = {
 329         .open           = idma_open,
 330         .close          = idma_close,
 331         .ioctl          = snd_pcm_lib_ioctl,
 332         .trigger        = idma_trigger,
 333         .pointer        = idma_pointer,
 334         .mmap           = idma_mmap,
 335         .hw_params      = idma_hw_params,
 336         .hw_free        = idma_hw_free,
 337         .prepare        = idma_prepare,
 338 };
 339
 340 static void idma_free(struct snd_pcm *pcm)
 341 {
 342         struct snd_pcm_substream *substream;
 343         struct snd_dma_buffer *buf;
 344
 345         substream = pcm->streams[SNDRV_PCM_STREAM_PLAYBACK].substream;
 346         if (!substream)
 347                 return;
 348
 349         buf = &substream->dma_buffer;
 350         if (!buf->area)
 351                 return;
 352
 353         iounmap((void __iomem *)buf->area);
 354
 355         buf->area = NULL;
 356         buf->addr = 0;
 357 }
 358
 359 static int preallocate_idma_buffer(struct snd_pcm *pcm, int stream)
 360 {
 361         struct snd_pcm_substream *substream = pcm->streams[stream].substream;
 362         struct snd_dma_buffer *buf = &substream->dma_buffer;
 363
 364         buf->dev.dev = pcm->card->dev;
 365         buf->private_data = NULL;
 366
 367         /* Assign PCM buffer pointers */
 368         buf->dev.type = SNDRV_DMA_TYPE_CONTINUOUS;
 369         buf->addr = idma.lp_tx_addr;
 370         buf->bytes = idma_hardware.buffer_bytes_max;
 371         buf->area = (unsigned char * __force)ioremap(buf->addr, buf->bytes);
 372
 373         return 0;
 374 }
 375
 376 static int idma_new(struct snd_soc_pcm_runtime *rtd)
 377 {
 378         struct snd_card *card = rtd->card->snd_card;
 379         struct snd_pcm *pcm = rtd->pcm;
 380         int ret;
 381
 382         ret = dma_coerce_mask_and_coherent(card->dev, DMA_BIT_MASK(32));
 383         if (ret)
 384                 return ret;
 385
 386         if (pcm->streams[SNDRV_PCM_STREAM_PLAYBACK].substream) {
 387                 ret = preallocate_idma_buffer(pcm,
 388                                 SNDRV_PCM_STREAM_PLAYBACK);
 389         }
 390
 391         return ret;
 392 }
 393
 394 void idma_reg_addr_init(void __iomem *regs, dma_addr_t addr)
 395 {
 396         spin_lock_init(&idma.lock);
 397         idma.regs = regs;
 398         idma.lp_tx_addr = addr;
 399 }
 400 EXPORT_SYMBOL_GPL(idma_reg_addr_init);
 401
 402 static const struct snd_soc_platform_driver asoc_idma_platform = {
 403         .ops = &idma_ops,
 404         .pcm_new = idma_new,
 405         .pcm_free = idma_free,
 406 };
 407
 408 static int asoc_idma_platform_probe(struct platform_device *pdev)
 409 {
 410         idma_irq = platform_get_irq(pdev, 0);
 411         if (idma_irq < 0)
 412                 return idma_irq;
 413
 414         return devm_snd_soc_register_platform(&pdev->dev, &asoc_idma_platform);
 415 }
 416
 417 static struct platform_driver asoc_idma_driver = {
 418         .driver = {
 419                 .name = "samsung-idma",
 420         },
 421
 422         .probe = asoc_idma_platform_probe,
 423 };
 424
 425 module_platform_driver(asoc_idma_driver);
 426
 427 MODULE_AUTHOR("Jaswinder Singh, <jassisinghbrar@gmail.com>");
 428 MODULE_DESCRIPTION("Samsung ASoC IDMA Driver");
 429 MODULE_LICENSE("GPL");