linux/sound/soc/samsung/idma.c
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   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
  24static 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
  38struct 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
  50static struct idma_info {
  51        spinlock_t      lock;
  52        void             __iomem  *regs;
  53        dma_addr_t      lp_tx_addr;
  54} idma;
  55
  56static int idma_irq;
  57
  58static void idma_getpos(dma_addr_t *src)
  59{
  60        *src = idma.lp_tx_addr +
  61                (readl(idma.regs + I2STRNCNT) & 0xffffff) * 4;
  62}
  63
  64static 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
  99static 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
 109static 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
 131static 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
 140static int idma_hw_params(struct snd_soc_component *component,
 141                          struct snd_pcm_substream *substream,
 142                          struct snd_pcm_hw_params *params)
 143{
 144        struct snd_pcm_runtime *runtime = substream->runtime;
 145        struct idma_ctrl *prtd = substream->runtime->private_data;
 146        u32 mod = readl(idma.regs + I2SMOD);
 147        u32 ahb = readl(idma.regs + I2SAHB);
 148
 149        ahb |= (AHB_DMARLD | AHB_INTMASK);
 150        mod |= MOD_TXS_IDMA;
 151        writel(ahb, idma.regs + I2SAHB);
 152        writel(mod, idma.regs + I2SMOD);
 153
 154        snd_pcm_set_runtime_buffer(substream, &substream->dma_buffer);
 155        runtime->dma_bytes = params_buffer_bytes(params);
 156
 157        prtd->start = prtd->pos = runtime->dma_addr;
 158        prtd->period = params_periods(params);
 159        prtd->periodsz = params_period_bytes(params);
 160        prtd->end = runtime->dma_addr + runtime->dma_bytes;
 161
 162        idma_setcallbk(substream, idma_done);
 163
 164        return 0;
 165}
 166
 167static int idma_hw_free(struct snd_soc_component *component,
 168                        struct snd_pcm_substream *substream)
 169{
 170        snd_pcm_set_runtime_buffer(substream, NULL);
 171
 172        return 0;
 173}
 174
 175static int idma_prepare(struct snd_soc_component *component,
 176                        struct snd_pcm_substream *substream)
 177{
 178        struct idma_ctrl *prtd = substream->runtime->private_data;
 179
 180        prtd->pos = prtd->start;
 181
 182        /* flush the DMA channel */
 183        idma_control(LPAM_DMA_STOP);
 184        idma_enqueue(substream);
 185
 186        return 0;
 187}
 188
 189static int idma_trigger(struct snd_soc_component *component,
 190                        struct snd_pcm_substream *substream, int cmd)
 191{
 192        struct idma_ctrl *prtd = substream->runtime->private_data;
 193        int ret = 0;
 194
 195        spin_lock(&prtd->lock);
 196
 197        switch (cmd) {
 198        case SNDRV_PCM_TRIGGER_RESUME:
 199        case SNDRV_PCM_TRIGGER_START:
 200        case SNDRV_PCM_TRIGGER_PAUSE_RELEASE:
 201                prtd->state |= ST_RUNNING;
 202                idma_control(LPAM_DMA_START);
 203                break;
 204
 205        case SNDRV_PCM_TRIGGER_SUSPEND:
 206        case SNDRV_PCM_TRIGGER_STOP:
 207        case SNDRV_PCM_TRIGGER_PAUSE_PUSH:
 208                prtd->state &= ~ST_RUNNING;
 209                idma_control(LPAM_DMA_STOP);
 210                break;
 211
 212        default:
 213                ret = -EINVAL;
 214                break;
 215        }
 216
 217        spin_unlock(&prtd->lock);
 218
 219        return ret;
 220}
 221
 222static snd_pcm_uframes_t
 223idma_pointer(struct snd_soc_component *component,
 224             struct snd_pcm_substream *substream)
 225{
 226        struct snd_pcm_runtime *runtime = substream->runtime;
 227        struct idma_ctrl *prtd = runtime->private_data;
 228        dma_addr_t src;
 229        unsigned long res;
 230
 231        spin_lock(&prtd->lock);
 232
 233        idma_getpos(&src);
 234        res = src - prtd->start;
 235
 236        spin_unlock(&prtd->lock);
 237
 238        return bytes_to_frames(substream->runtime, res);
 239}
 240
 241static int idma_mmap(struct snd_soc_component *component,
 242                     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
 248        /* From snd_pcm_lib_mmap_iomem */
 249        vma->vm_page_prot = pgprot_noncached(vma->vm_page_prot);
 250        size = vma->vm_end - vma->vm_start;
 251        offset = vma->vm_pgoff << PAGE_SHIFT;
 252        return io_remap_pfn_range(vma, vma->vm_start,
 253                        (runtime->dma_addr + offset) >> PAGE_SHIFT,
 254                        size, vma->vm_page_prot);
 255}
 256
 257static irqreturn_t iis_irq(int irqno, void *dev_id)
 258{
 259        struct idma_ctrl *prtd = (struct idma_ctrl *)dev_id;
 260        u32 iisahb, val, addr;
 261
 262        iisahb  = readl(idma.regs + I2SAHB);
 263
 264        val = (iisahb & AHB_LVL0INT) ? AHB_CLRLVL0INT : 0;
 265
 266        if (val) {
 267                iisahb |= val;
 268                writel(iisahb, idma.regs + I2SAHB);
 269
 270                addr = readl(idma.regs + I2SLVL0ADDR) - idma.lp_tx_addr;
 271                addr += prtd->periodsz;
 272                addr %= (u32)(prtd->end - prtd->start);
 273                addr += idma.lp_tx_addr;
 274
 275                writel(addr, idma.regs + I2SLVL0ADDR);
 276
 277                if (prtd->cb)
 278                        prtd->cb(prtd->token, prtd->period);
 279        }
 280
 281        return IRQ_HANDLED;
 282}
 283
 284static int idma_open(struct snd_soc_component *component,
 285                     struct snd_pcm_substream *substream)
 286{
 287        struct snd_pcm_runtime *runtime = substream->runtime;
 288        struct idma_ctrl *prtd;
 289        int ret;
 290
 291        snd_soc_set_runtime_hwparams(substream, &idma_hardware);
 292
 293        prtd = kzalloc(sizeof(struct idma_ctrl), GFP_KERNEL);
 294        if (prtd == NULL)
 295                return -ENOMEM;
 296
 297        ret = request_irq(idma_irq, iis_irq, 0, "i2s", prtd);
 298        if (ret < 0) {
 299                pr_err("fail to claim i2s irq , ret = %d\n", ret);
 300                kfree(prtd);
 301                return ret;
 302        }
 303
 304        spin_lock_init(&prtd->lock);
 305
 306        runtime->private_data = prtd;
 307
 308        return 0;
 309}
 310
 311static int idma_close(struct snd_soc_component *component,
 312                      struct snd_pcm_substream *substream)
 313{
 314        struct snd_pcm_runtime *runtime = substream->runtime;
 315        struct idma_ctrl *prtd = runtime->private_data;
 316
 317        free_irq(idma_irq, prtd);
 318
 319        if (!prtd)
 320                pr_err("idma_close called with prtd == NULL\n");
 321
 322        kfree(prtd);
 323
 324        return 0;
 325}
 326
 327static void idma_free(struct snd_soc_component *component,
 328                      struct snd_pcm *pcm)
 329{
 330        struct snd_pcm_substream *substream;
 331        struct snd_dma_buffer *buf;
 332
 333        substream = pcm->streams[SNDRV_PCM_STREAM_PLAYBACK].substream;
 334        if (!substream)
 335                return;
 336
 337        buf = &substream->dma_buffer;
 338        if (!buf->area)
 339                return;
 340
 341        iounmap((void __iomem *)buf->area);
 342
 343        buf->area = NULL;
 344        buf->addr = 0;
 345}
 346
 347static int preallocate_idma_buffer(struct snd_pcm *pcm, int stream)
 348{
 349        struct snd_pcm_substream *substream = pcm->streams[stream].substream;
 350        struct snd_dma_buffer *buf = &substream->dma_buffer;
 351
 352        buf->dev.dev = pcm->card->dev;
 353        buf->private_data = NULL;
 354
 355        /* Assign PCM buffer pointers */
 356        buf->dev.type = SNDRV_DMA_TYPE_CONTINUOUS;
 357        buf->addr = idma.lp_tx_addr;
 358        buf->bytes = idma_hardware.buffer_bytes_max;
 359        buf->area = (unsigned char * __force)ioremap(buf->addr, buf->bytes);
 360        if (!buf->area)
 361                return -ENOMEM;
 362
 363        return 0;
 364}
 365
 366static int idma_new(struct snd_soc_component *component,
 367                    struct snd_soc_pcm_runtime *rtd)
 368{
 369        struct snd_card *card = rtd->card->snd_card;
 370        struct snd_pcm *pcm = rtd->pcm;
 371        int ret;
 372
 373        ret = dma_coerce_mask_and_coherent(card->dev, DMA_BIT_MASK(32));
 374        if (ret)
 375                return ret;
 376
 377        if (pcm->streams[SNDRV_PCM_STREAM_PLAYBACK].substream) {
 378                ret = preallocate_idma_buffer(pcm,
 379                                SNDRV_PCM_STREAM_PLAYBACK);
 380        }
 381
 382        return ret;
 383}
 384
 385void idma_reg_addr_init(void __iomem *regs, dma_addr_t addr)
 386{
 387        spin_lock_init(&idma.lock);
 388        idma.regs = regs;
 389        idma.lp_tx_addr = addr;
 390}
 391EXPORT_SYMBOL_GPL(idma_reg_addr_init);
 392
 393static const struct snd_soc_component_driver asoc_idma_platform = {
 394        .open           = idma_open,
 395        .close          = idma_close,
 396        .trigger        = idma_trigger,
 397        .pointer        = idma_pointer,
 398        .mmap           = idma_mmap,
 399        .hw_params      = idma_hw_params,
 400        .hw_free        = idma_hw_free,
 401        .prepare        = idma_prepare,
 402        .pcm_construct  = idma_new,
 403        .pcm_destruct   = idma_free,
 404};
 405
 406static int asoc_idma_platform_probe(struct platform_device *pdev)
 407{
 408        idma_irq = platform_get_irq(pdev, 0);
 409        if (idma_irq < 0)
 410                return idma_irq;
 411
 412        return devm_snd_soc_register_component(&pdev->dev, &asoc_idma_platform,
 413                                               NULL, 0);
 414}
 415
 416static struct platform_driver asoc_idma_driver = {
 417        .driver = {
 418                .name = "samsung-idma",
 419        },
 420
 421        .probe = asoc_idma_platform_probe,
 422};
 423
 424module_platform_driver(asoc_idma_driver);
 425
 426MODULE_AUTHOR("Jaswinder Singh, <jassisinghbrar@gmail.com>");
 427MODULE_DESCRIPTION("Samsung ASoC IDMA Driver");
 428MODULE_LICENSE("GPL");
 429