sound/soc/samsung/idma.c

   1 // SPDX-License-Identifier: GPL-2.0+
   2 //
   3 // idma.c - I2S0 internal DMA driver
   4 //
   5 // Copyright (c) 2011 Samsung Electronics Co., Ltd.
   6 //              http://www.samsung.com
   7
   8 #include <linux/interrupt.h>
   9 #include <linux/platform_device.h>
  10 #include <linux/dma-mapping.h>
  11 #include <linux/slab.h>
  12 #include <linux/module.h>
  13 #include <sound/pcm.h>
  14 #include <sound/pcm_params.h>
  15 #include <sound/soc.h>
  16
  17 #include "i2s.h"
  18 #include "idma.h"
  19 #include "i2s-regs.h"
  20
  21 #define ST_RUNNING              (1<<0)
  22 #define ST_OPENED               (1<<1)
  23
  24 static const struct snd_pcm_hardware idma_hardware = {
  25         .info = SNDRV_PCM_INFO_INTERLEAVED |
  26                     SNDRV_PCM_INFO_BLOCK_TRANSFER |
  27                     SNDRV_PCM_INFO_MMAP |
  28                     SNDRV_PCM_INFO_MMAP_VALID |
  29                     SNDRV_PCM_INFO_PAUSE |
  30                     SNDRV_PCM_INFO_RESUME,
  31         .buffer_bytes_max = MAX_IDMA_BUFFER,
  32         .period_bytes_min = 128,
  33         .period_bytes_max = MAX_IDMA_PERIOD,
  34         .periods_min = 1,
  35         .periods_max = 2,
  36 };
  37
  38 struct idma_ctrl {
  39         spinlock_t      lock;
  40         int             state;
  41         dma_addr_t      start;
  42         dma_addr_t      pos;
  43         dma_addr_t      end;
  44         dma_addr_t      period;
  45         dma_addr_t      periodsz;
  46         void            *token;
  47         void            (*cb)(void *dt, int bytes_xfer);
  48 };
  49
  50 static struct idma_info {
  51         spinlock_t      lock;
  52         void             __iomem  *regs;
  53         dma_addr_t      lp_tx_addr;
  54 } idma;
  55
  56 static int idma_irq;
  57
  58 static void idma_getpos(dma_addr_t *src)
  59 {
  60         *src = idma.lp_tx_addr +
  61                 (readl(idma.regs + I2STRNCNT) & 0xffffff) * 4;
  62 }
  63
  64 static int idma_enqueue(struct snd_pcm_substream *substream)
  65 {
  66         struct snd_pcm_runtime *runtime = substream->runtime;
  67         struct idma_ctrl *prtd = substream->runtime->private_data;
  68         u32 val;
  69
  70         spin_lock(&prtd->lock);
  71         prtd->token = (void *) substream;
  72         spin_unlock(&prtd->lock);
  73
  74         /* Internal DMA Level0 Interrupt Address */
  75         val = idma.lp_tx_addr + prtd->periodsz;
  76         writel(val, idma.regs + I2SLVL0ADDR);
  77
  78         /* Start address0 of I2S internal DMA operation. */
  79         val = idma.lp_tx_addr;
  80         writel(val, idma.regs + I2SSTR0);
  81
  82         /*
  83          * Transfer block size for I2S internal DMA.
  84          * Should decide transfer size before start dma operation
  85          */
  86         val = readl(idma.regs + I2SSIZE);
  87         val &= ~(I2SSIZE_TRNMSK << I2SSIZE_SHIFT);
  88         val |= (((runtime->dma_bytes >> 2) &
  89                         I2SSIZE_TRNMSK) << I2SSIZE_SHIFT);
  90         writel(val, idma.regs + I2SSIZE);
  91
  92         val = readl(idma.regs + I2SAHB);
  93         val |= AHB_INTENLVL0;
  94         writel(val, idma.regs + I2SAHB);
  95
  96         return 0;
  97 }
  98
  99 static void idma_setcallbk(struct snd_pcm_substream *substream,
 100                                 void (*cb)(void *, int))
 101 {
 102         struct idma_ctrl *prtd = substream->runtime->private_data;
 103
 104         spin_lock(&prtd->lock);
 105         prtd->cb = cb;
 106         spin_unlock(&prtd->lock);
 107 }
 108
 109 static void idma_control(int op)
 110 {
 111         u32 val = readl(idma.regs + I2SAHB);
 112
 113         spin_lock(&idma.lock);
 114
 115         switch (op) {
 116         case LPAM_DMA_START:
 117                 val |= (AHB_INTENLVL0 | AHB_DMAEN);
 118                 break;
 119         case LPAM_DMA_STOP:
 120                 val &= ~(AHB_INTENLVL0 | AHB_DMAEN);
 121                 break;
 122         default:
 123                 spin_unlock(&idma.lock);
 124                 return;
 125         }
 126
 127         writel(val, idma.regs + I2SAHB);
 128         spin_unlock(&idma.lock);
 129 }
 130
 131 static void idma_done(void *id, int bytes_xfer)
 132 {
 133         struct snd_pcm_substream *substream = id;
 134         struct idma_ctrl *prtd = substream->runtime->private_data;
 135
 136         if (prtd && (prtd->state & ST_RUNNING))
 137                 snd_pcm_period_elapsed(substream);
 138 }
 139
 140 static int idma_hw_params(struct snd_pcm_substream *substream,
 141                                 struct snd_pcm_hw_params *params)
 142 {
 143         struct snd_pcm_runtime *runtime = substream->runtime;
 144         struct idma_ctrl *prtd = substream->runtime->private_data;
 145         u32 mod = readl(idma.regs + I2SMOD);
 146         u32 ahb = readl(idma.regs + I2SAHB);
 147
 148         ahb |= (AHB_DMARLD | AHB_INTMASK);
 149         mod |= MOD_TXS_IDMA;
 150         writel(ahb, idma.regs + I2SAHB);
 151         writel(mod, idma.regs + I2SMOD);
 152
 153         snd_pcm_set_runtime_buffer(substream, &substream->dma_buffer);
 154         runtime->dma_bytes = params_buffer_bytes(params);
 155
 156         prtd->start = prtd->pos = runtime->dma_addr;
 157         prtd->period = params_periods(params);
 158         prtd->periodsz = params_period_bytes(params);
 159         prtd->end = runtime->dma_addr + runtime->dma_bytes;
 160
 161         idma_setcallbk(substream, idma_done);
 162
 163         return 0;
 164 }
 165
 166 static int idma_hw_free(struct snd_pcm_substream *substream)
 167 {
 168         snd_pcm_set_runtime_buffer(substream, NULL);
 169
 170         return 0;
 171 }
 172
 173 static int idma_prepare(struct snd_pcm_substream *substream)
 174 {
 175         struct idma_ctrl *prtd = substream->runtime->private_data;
 176
 177         prtd->pos = prtd->start;
 178
 179         /* flush the DMA channel */
 180         idma_control(LPAM_DMA_STOP);
 181         idma_enqueue(substream);
 182
 183         return 0;
 184 }
 185
 186 static int idma_trigger(struct snd_pcm_substream *substream, int cmd)
 187 {
 188         struct idma_ctrl *prtd = substream->runtime->private_data;
 189         int ret = 0;
 190
 191         spin_lock(&prtd->lock);
 192
 193         switch (cmd) {
 194         case SNDRV_PCM_TRIGGER_RESUME:
 195         case SNDRV_PCM_TRIGGER_START:
 196         case SNDRV_PCM_TRIGGER_PAUSE_RELEASE:
 197                 prtd->state |= ST_RUNNING;
 198                 idma_control(LPAM_DMA_START);
 199                 break;
 200
 201         case SNDRV_PCM_TRIGGER_SUSPEND:
 202         case SNDRV_PCM_TRIGGER_STOP:
 203         case SNDRV_PCM_TRIGGER_PAUSE_PUSH:
 204                 prtd->state &= ~ST_RUNNING;
 205                 idma_control(LPAM_DMA_STOP);
 206                 break;
 207
 208         default:
 209                 ret = -EINVAL;
 210                 break;
 211         }
 212
 213         spin_unlock(&prtd->lock);
 214
 215         return ret;
 216 }
 217
 218 static snd_pcm_uframes_t
 219         idma_pointer(struct snd_pcm_substream *substream)
 220 {
 221         struct snd_pcm_runtime *runtime = substream->runtime;
 222         struct idma_ctrl *prtd = runtime->private_data;
 223         dma_addr_t src;
 224         unsigned long res;
 225
 226         spin_lock(&prtd->lock);
 227
 228         idma_getpos(&src);
 229         res = src - prtd->start;
 230
 231         spin_unlock(&prtd->lock);
 232
 233         return bytes_to_frames(substream->runtime, res);
 234 }
 235
 236 static int idma_mmap(struct snd_pcm_substream *substream,
 237         struct vm_area_struct *vma)
 238 {
 239         struct snd_pcm_runtime *runtime = substream->runtime;
 240         unsigned long size, offset;
 241         int ret;
 242
 243         /* From snd_pcm_lib_mmap_iomem */
 244         vma->vm_page_prot = pgprot_noncached(vma->vm_page_prot);
 245         size = vma->vm_end - vma->vm_start;
 246         offset = vma->vm_pgoff << PAGE_SHIFT;
 247         ret = io_remap_pfn_range(vma, vma->vm_start,
 248                         (runtime->dma_addr + offset) >> PAGE_SHIFT,
 249                         size, vma->vm_page_prot);
 250
 251         return ret;
 252 }
 253
 254 static irqreturn_t iis_irq(int irqno, void *dev_id)
 255 {
 256         struct idma_ctrl *prtd = (struct idma_ctrl *)dev_id;
 257         u32 iisahb, val, addr;
 258
 259         iisahb  = readl(idma.regs + I2SAHB);
 260
 261         val = (iisahb & AHB_LVL0INT) ? AHB_CLRLVL0INT : 0;
 262
 263         if (val) {
 264                 iisahb |= val;
 265                 writel(iisahb, idma.regs + I2SAHB);
 266
 267                 addr = readl(idma.regs + I2SLVL0ADDR) - idma.lp_tx_addr;
 268                 addr += prtd->periodsz;
 269                 addr %= (u32)(prtd->end - prtd->start);
 270                 addr += idma.lp_tx_addr;
 271
 272                 writel(addr, idma.regs + I2SLVL0ADDR);
 273
 274                 if (prtd->cb)
 275                         prtd->cb(prtd->token, prtd->period);
 276         }
 277
 278         return IRQ_HANDLED;
 279 }
 280
 281 static int idma_open(struct snd_pcm_substream *substream)
 282 {
 283         struct snd_pcm_runtime *runtime = substream->runtime;
 284         struct idma_ctrl *prtd;
 285         int ret;
 286
 287         snd_soc_set_runtime_hwparams(substream, &idma_hardware);
 288
 289         prtd = kzalloc(sizeof(struct idma_ctrl), GFP_KERNEL);
 290         if (prtd == NULL)
 291                 return -ENOMEM;
 292
 293         ret = request_irq(idma_irq, iis_irq, 0, "i2s", prtd);
 294         if (ret < 0) {
 295                 pr_err("fail to claim i2s irq , ret = %d\n", ret);
 296                 kfree(prtd);
 297                 return ret;
 298         }
 299
 300         spin_lock_init(&prtd->lock);
 301
 302         runtime->private_data = prtd;
 303
 304         return 0;
 305 }
 306
 307 static int idma_close(struct snd_pcm_substream *substream)
 308 {
 309         struct snd_pcm_runtime *runtime = substream->runtime;
 310         struct idma_ctrl *prtd = runtime->private_data;
 311
 312         free_irq(idma_irq, prtd);
 313
 314         if (!prtd)
 315                 pr_err("idma_close called with prtd == NULL\n");
 316
 317         kfree(prtd);
 318
 319         return 0;
 320 }
 321
 322 static const struct snd_pcm_ops idma_ops = {
 323         .open           = idma_open,
 324         .close          = idma_close,
 325         .ioctl          = snd_pcm_lib_ioctl,
 326         .trigger        = idma_trigger,
 327         .pointer        = idma_pointer,
 328         .mmap           = idma_mmap,
 329         .hw_params      = idma_hw_params,
 330         .hw_free        = idma_hw_free,
 331         .prepare        = idma_prepare,
 332 };
 333
 334 static void idma_free(struct snd_pcm *pcm)
 335 {
 336         struct snd_pcm_substream *substream;
 337         struct snd_dma_buffer *buf;
 338
 339         substream = pcm->streams[SNDRV_PCM_STREAM_PLAYBACK].substream;
 340         if (!substream)
 341                 return;
 342
 343         buf = &substream->dma_buffer;
 344         if (!buf->area)
 345                 return;
 346
 347         iounmap((void __iomem *)buf->area);
 348
 349         buf->area = NULL;
 350         buf->addr = 0;
 351 }
 352
 353 static int preallocate_idma_buffer(struct snd_pcm *pcm, int stream)
 354 {
 355         struct snd_pcm_substream *substream = pcm->streams[stream].substream;
 356         struct snd_dma_buffer *buf = &substream->dma_buffer;
 357
 358         buf->dev.dev = pcm->card->dev;
 359         buf->private_data = NULL;
 360
 361         /* Assign PCM buffer pointers */
 362         buf->dev.type = SNDRV_DMA_TYPE_CONTINUOUS;
 363         buf->addr = idma.lp_tx_addr;
 364         buf->bytes = idma_hardware.buffer_bytes_max;
 365         buf->area = (unsigned char * __force)ioremap(buf->addr, buf->bytes);
 366
 367         return 0;
 368 }
 369
 370 static int idma_new(struct snd_soc_pcm_runtime *rtd)
 371 {
 372         struct snd_card *card = rtd->card->snd_card;
 373         struct snd_pcm *pcm = rtd->pcm;
 374         int ret;
 375
 376         ret = dma_coerce_mask_and_coherent(card->dev, DMA_BIT_MASK(32));
 377         if (ret)
 378                 return ret;
 379
 380         if (pcm->streams[SNDRV_PCM_STREAM_PLAYBACK].substream) {
 381                 ret = preallocate_idma_buffer(pcm,
 382                                 SNDRV_PCM_STREAM_PLAYBACK);
 383         }
 384
 385         return ret;
 386 }
 387
 388 void idma_reg_addr_init(void __iomem *regs, dma_addr_t addr)
 389 {
 390         spin_lock_init(&idma.lock);
 391         idma.regs = regs;
 392         idma.lp_tx_addr = addr;
 393 }
 394 EXPORT_SYMBOL_GPL(idma_reg_addr_init);
 395
 396 static const struct snd_soc_component_driver asoc_idma_platform = {
 397         .ops = &idma_ops,
 398         .pcm_new = idma_new,
 399         .pcm_free = idma_free,
 400 };
 401
 402 static int asoc_idma_platform_probe(struct platform_device *pdev)
 403 {
 404         idma_irq = platform_get_irq(pdev, 0);
 405         if (idma_irq < 0)
 406                 return idma_irq;
 407
 408         return devm_snd_soc_register_component(&pdev->dev, &asoc_idma_platform,
 409                                                NULL, 0);
 410 }
 411
 412 static struct platform_driver asoc_idma_driver = {
 413         .driver = {
 414                 .name = "samsung-idma",
 415         },
 416
 417         .probe = asoc_idma_platform_probe,
 418 };
 419
 420 module_platform_driver(asoc_idma_driver);
 421
 422 MODULE_AUTHOR("Jaswinder Singh, <jassisinghbrar@gmail.com>");
 423 MODULE_DESCRIPTION("Samsung ASoC IDMA Driver");
 424 MODULE_LICENSE("GPL");