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