sound/soc/imx/imx-pcm-fiq.c

   1 /*
   2  * imx-pcm-fiq.c  --  ALSA Soc Audio Layer
   3  *
   4  * Copyright 2009 Sascha Hauer <s.hauer@pengutronix.de>
   5  *
   6  * This code is based on code copyrighted by Freescale,
   7  * Liam Girdwood, Javier Martin and probably others.
   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/clk.h>
  15 #include <linux/delay.h>
  16 #include <linux/device.h>
  17 #include <linux/dma-mapping.h>
  18 #include <linux/init.h>
  19 #include <linux/interrupt.h>
  20 #include <linux/module.h>
  21 #include <linux/platform_device.h>
  22 #include <linux/slab.h>
  23
  24 #include <sound/core.h>
  25 #include <sound/initval.h>
  26 #include <sound/pcm.h>
  27 #include <sound/pcm_params.h>
  28 #include <sound/soc.h>
  29
  30 #include <asm/fiq.h>
  31
  32 #include <mach/ssi.h>
  33
  34 #include "imx-ssi.h"
  35
  36 struct imx_pcm_runtime_data {
  37         int period;
  38         int periods;
  39         unsigned long offset;
  40         unsigned long last_offset;
  41         unsigned long size;
  42         struct hrtimer hrt;
  43         int poll_time_ns;
  44         struct snd_pcm_substream *substream;
  45         atomic_t running;
  46 };
  47
  48 static enum hrtimer_restart snd_hrtimer_callback(struct hrtimer *hrt)
  49 {
  50         struct imx_pcm_runtime_data *iprtd =
  51                 container_of(hrt, struct imx_pcm_runtime_data, hrt);
  52         struct snd_pcm_substream *substream = iprtd->substream;
  53         struct snd_pcm_runtime *runtime = substream->runtime;
  54         struct pt_regs regs;
  55         unsigned long delta;
  56
  57         if (!atomic_read(&iprtd->running))
  58                 return HRTIMER_NORESTART;
  59
  60         get_fiq_regs(&regs);
  61
  62         if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK)
  63                 iprtd->offset = regs.ARM_r8 & 0xffff;
  64         else
  65                 iprtd->offset = regs.ARM_r9 & 0xffff;
  66
  67         /* How much data have we transferred since the last period report? */
  68         if (iprtd->offset >= iprtd->last_offset)
  69                 delta = iprtd->offset - iprtd->last_offset;
  70         else
  71                 delta = runtime->buffer_size + iprtd->offset
  72                         - iprtd->last_offset;
  73
  74         /* If we've transferred at least a period then report it and
  75          * reset our poll time */
  76         if (delta >= iprtd->period) {
  77                 snd_pcm_period_elapsed(substream);
  78                 iprtd->last_offset = iprtd->offset;
  79         }
  80
  81         hrtimer_forward_now(hrt, ns_to_ktime(iprtd->poll_time_ns));
  82
  83         return HRTIMER_RESTART;
  84 }
  85
  86 static struct fiq_handler fh = {
  87         .name           = DRV_NAME,
  88 };
  89
  90 static int snd_imx_pcm_hw_params(struct snd_pcm_substream *substream,
  91                                 struct snd_pcm_hw_params *params)
  92 {
  93         struct snd_pcm_runtime *runtime = substream->runtime;
  94         struct imx_pcm_runtime_data *iprtd = runtime->private_data;
  95
  96         iprtd->size = params_buffer_bytes(params);
  97         iprtd->periods = params_periods(params);
  98         iprtd->period = params_period_bytes(params) ;
  99         iprtd->offset = 0;
 100         iprtd->last_offset = 0;
 101         iprtd->poll_time_ns = 1000000000 / params_rate(params) *
 102                                 params_period_size(params);
 103         snd_pcm_set_runtime_buffer(substream, &substream->dma_buffer);
 104
 105         return 0;
 106 }
 107
 108 static int snd_imx_pcm_prepare(struct snd_pcm_substream *substream)
 109 {
 110         struct snd_pcm_runtime *runtime = substream->runtime;
 111         struct imx_pcm_runtime_data *iprtd = runtime->private_data;
 112         struct pt_regs regs;
 113
 114         get_fiq_regs(&regs);
 115         if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK)
 116                 regs.ARM_r8 = (iprtd->period * iprtd->periods - 1) << 16;
 117         else
 118                 regs.ARM_r9 = (iprtd->period * iprtd->periods - 1) << 16;
 119
 120         set_fiq_regs(&regs);
 121
 122         return 0;
 123 }
 124
 125 static int fiq_enable;
 126 static int imx_pcm_fiq;
 127
 128 static int snd_imx_pcm_trigger(struct snd_pcm_substream *substream, int cmd)
 129 {
 130         struct snd_pcm_runtime *runtime = substream->runtime;
 131         struct imx_pcm_runtime_data *iprtd = runtime->private_data;
 132
 133         switch (cmd) {
 134         case SNDRV_PCM_TRIGGER_START:
 135         case SNDRV_PCM_TRIGGER_RESUME:
 136         case SNDRV_PCM_TRIGGER_PAUSE_RELEASE:
 137                 atomic_set(&iprtd->running, 1);
 138                 hrtimer_start(&iprtd->hrt, ns_to_ktime(iprtd->poll_time_ns),
 139                       HRTIMER_MODE_REL);
 140                 if (++fiq_enable == 1)
 141                         enable_fiq(imx_pcm_fiq);
 142
 143                 break;
 144
 145         case SNDRV_PCM_TRIGGER_STOP:
 146         case SNDRV_PCM_TRIGGER_SUSPEND:
 147         case SNDRV_PCM_TRIGGER_PAUSE_PUSH:
 148                 atomic_set(&iprtd->running, 0);
 149
 150                 if (--fiq_enable == 0)
 151                         disable_fiq(imx_pcm_fiq);
 152
 153                 break;
 154         default:
 155                 return -EINVAL;
 156         }
 157
 158         return 0;
 159 }
 160
 161 static snd_pcm_uframes_t snd_imx_pcm_pointer(struct snd_pcm_substream *substream)
 162 {
 163         struct snd_pcm_runtime *runtime = substream->runtime;
 164         struct imx_pcm_runtime_data *iprtd = runtime->private_data;
 165
 166         return bytes_to_frames(substream->runtime, iprtd->offset);
 167 }
 168
 169 static struct snd_pcm_hardware snd_imx_hardware = {
 170         .info = SNDRV_PCM_INFO_INTERLEAVED |
 171                 SNDRV_PCM_INFO_BLOCK_TRANSFER |
 172                 SNDRV_PCM_INFO_MMAP |
 173                 SNDRV_PCM_INFO_MMAP_VALID |
 174                 SNDRV_PCM_INFO_PAUSE |
 175                 SNDRV_PCM_INFO_RESUME,
 176         .formats = SNDRV_PCM_FMTBIT_S16_LE,
 177         .rate_min = 8000,
 178         .channels_min = 2,
 179         .channels_max = 2,
 180         .buffer_bytes_max = IMX_SSI_DMABUF_SIZE,
 181         .period_bytes_min = 128,
 182         .period_bytes_max = 16 * 1024,
 183         .periods_min = 4,
 184         .periods_max = 255,
 185         .fifo_size = 0,
 186 };
 187
 188 static int snd_imx_open(struct snd_pcm_substream *substream)
 189 {
 190         struct snd_pcm_runtime *runtime = substream->runtime;
 191         struct imx_pcm_runtime_data *iprtd;
 192         int ret;
 193
 194         iprtd = kzalloc(sizeof(*iprtd), GFP_KERNEL);
 195         if (iprtd == NULL)
 196                 return -ENOMEM;
 197         runtime->private_data = iprtd;
 198
 199         iprtd->substream = substream;
 200
 201         atomic_set(&iprtd->running, 0);
 202         hrtimer_init(&iprtd->hrt, CLOCK_MONOTONIC, HRTIMER_MODE_REL);
 203         iprtd->hrt.function = snd_hrtimer_callback;
 204
 205         ret = snd_pcm_hw_constraint_integer(substream->runtime,
 206                         SNDRV_PCM_HW_PARAM_PERIODS);
 207         if (ret < 0) {
 208                 kfree(iprtd);
 209                 return ret;
 210         }
 211
 212         snd_soc_set_runtime_hwparams(substream, &snd_imx_hardware);
 213         return 0;
 214 }
 215
 216 static int snd_imx_close(struct snd_pcm_substream *substream)
 217 {
 218         struct snd_pcm_runtime *runtime = substream->runtime;
 219         struct imx_pcm_runtime_data *iprtd = runtime->private_data;
 220
 221         hrtimer_cancel(&iprtd->hrt);
 222
 223         kfree(iprtd);
 224
 225         return 0;
 226 }
 227
 228 static struct snd_pcm_ops imx_pcm_ops = {
 229         .open           = snd_imx_open,
 230         .close          = snd_imx_close,
 231         .ioctl          = snd_pcm_lib_ioctl,
 232         .hw_params      = snd_imx_pcm_hw_params,
 233         .prepare        = snd_imx_pcm_prepare,
 234         .trigger        = snd_imx_pcm_trigger,
 235         .pointer        = snd_imx_pcm_pointer,
 236         .mmap           = snd_imx_pcm_mmap,
 237 };
 238
 239 static int ssi_irq = 0;
 240
 241 static int imx_pcm_fiq_new(struct snd_soc_pcm_runtime *rtd)
 242 {
 243         struct snd_pcm *pcm = rtd->pcm;
 244         struct snd_pcm_substream *substream;
 245         int ret;
 246
 247         ret = imx_pcm_new(rtd);
 248         if (ret)
 249                 return ret;
 250
 251         substream = pcm->streams[SNDRV_PCM_STREAM_PLAYBACK].substream;
 252         if (substream) {
 253                 struct snd_dma_buffer *buf = &substream->dma_buffer;
 254
 255                 imx_ssi_fiq_tx_buffer = (unsigned long)buf->area;
 256         }
 257
 258         substream = pcm->streams[SNDRV_PCM_STREAM_CAPTURE].substream;
 259         if (substream) {
 260                 struct snd_dma_buffer *buf = &substream->dma_buffer;
 261
 262                 imx_ssi_fiq_rx_buffer = (unsigned long)buf->area;
 263         }
 264
 265         set_fiq_handler(&imx_ssi_fiq_start,
 266                 &imx_ssi_fiq_end - &imx_ssi_fiq_start);
 267
 268         return 0;
 269 }
 270
 271 static void imx_pcm_fiq_free(struct snd_pcm *pcm)
 272 {
 273         mxc_set_irq_fiq(ssi_irq, 0);
 274         release_fiq(&fh);
 275         imx_pcm_free(pcm);
 276 }
 277
 278 static struct snd_soc_platform_driver imx_soc_platform_fiq = {
 279         .ops            = &imx_pcm_ops,
 280         .pcm_new        = imx_pcm_fiq_new,
 281         .pcm_free       = imx_pcm_fiq_free,
 282 };
 283
 284 static int __devinit imx_soc_platform_probe(struct platform_device *pdev)
 285 {
 286         struct imx_ssi *ssi = platform_get_drvdata(pdev);
 287         int ret;
 288
 289         ret = claim_fiq(&fh);
 290         if (ret) {
 291                 dev_err(&pdev->dev, "failed to claim fiq: %d", ret);
 292                 return ret;
 293         }
 294
 295         mxc_set_irq_fiq(ssi->irq, 1);
 296         ssi_irq = ssi->irq;
 297
 298         imx_pcm_fiq = ssi->irq;
 299
 300         imx_ssi_fiq_base = (unsigned long)ssi->base;
 301
 302         ssi->dma_params_tx.burstsize = 4;
 303         ssi->dma_params_rx.burstsize = 6;
 304
 305         ret = snd_soc_register_platform(&pdev->dev, &imx_soc_platform_fiq);
 306         if (ret)
 307                 goto failed_register;
 308
 309         return 0;
 310
 311 failed_register:
 312         mxc_set_irq_fiq(ssi_irq, 0);
 313         release_fiq(&fh);
 314
 315         return ret;
 316 }
 317
 318 static int __devexit imx_soc_platform_remove(struct platform_device *pdev)
 319 {
 320         snd_soc_unregister_platform(&pdev->dev);
 321         return 0;
 322 }
 323
 324 static struct platform_driver imx_pcm_driver = {
 325         .driver = {
 326                         .name = "imx-fiq-pcm-audio",
 327                         .owner = THIS_MODULE,
 328         },
 329
 330         .probe = imx_soc_platform_probe,
 331         .remove = __devexit_p(imx_soc_platform_remove),
 332 };
 333
 334 module_platform_driver(imx_pcm_driver);
 335
 336 MODULE_LICENSE("GPL");