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

   1 // SPDX-License-Identifier: GPL-2.0+
   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 #include <linux/clk.h>
  10 #include <linux/delay.h>
  11 #include <linux/device.h>
  12 #include <linux/dma-mapping.h>
  13 #include <linux/init.h>
  14 #include <linux/interrupt.h>
  15 #include <linux/module.h>
  16 #include <linux/platform_device.h>
  17 #include <linux/slab.h>
  18
  19 #include <sound/core.h>
  20 #include <sound/dmaengine_pcm.h>
  21 #include <sound/initval.h>
  22 #include <sound/pcm.h>
  23 #include <sound/pcm_params.h>
  24 #include <sound/soc.h>
  25
  26 #include <asm/fiq.h>
  27
  28 #include <linux/platform_data/asoc-imx-ssi.h>
  29
  30 #include "imx-ssi.h"
  31 #include "imx-pcm.h"
  32
  33 struct imx_pcm_runtime_data {
  34         unsigned int period;
  35         int periods;
  36         unsigned long offset;
  37         struct hrtimer hrt;
  38         int poll_time_ns;
  39         struct snd_pcm_substream *substream;
  40         atomic_t playing;
  41         atomic_t capturing;
  42 };
  43
  44 static enum hrtimer_restart snd_hrtimer_callback(struct hrtimer *hrt)
  45 {
  46         struct imx_pcm_runtime_data *iprtd =
  47                 container_of(hrt, struct imx_pcm_runtime_data, hrt);
  48         struct snd_pcm_substream *substream = iprtd->substream;
  49         struct pt_regs regs;
  50
  51         if (!atomic_read(&iprtd->playing) && !atomic_read(&iprtd->capturing))
  52                 return HRTIMER_NORESTART;
  53
  54         get_fiq_regs(&regs);
  55
  56         if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK)
  57                 iprtd->offset = regs.ARM_r8 & 0xffff;
  58         else
  59                 iprtd->offset = regs.ARM_r9 & 0xffff;
  60
  61         snd_pcm_period_elapsed(substream);
  62
  63         hrtimer_forward_now(hrt, ns_to_ktime(iprtd->poll_time_ns));
  64
  65         return HRTIMER_RESTART;
  66 }
  67
  68 static struct fiq_handler fh = {
  69         .name           = DRV_NAME,
  70 };
  71
  72 static int snd_imx_pcm_hw_params(struct snd_soc_component *component,
  73                                  struct snd_pcm_substream *substream,
  74                                  struct snd_pcm_hw_params *params)
  75 {
  76         struct snd_pcm_runtime *runtime = substream->runtime;
  77         struct imx_pcm_runtime_data *iprtd = runtime->private_data;
  78
  79         iprtd->periods = params_periods(params);
  80         iprtd->period = params_period_bytes(params);
  81         iprtd->offset = 0;
  82         iprtd->poll_time_ns = 1000000000 / params_rate(params) *
  83                                 params_period_size(params);
  84
  85         return 0;
  86 }
  87
  88 static int snd_imx_pcm_prepare(struct snd_soc_component *component,
  89                                struct snd_pcm_substream *substream)
  90 {
  91         struct snd_pcm_runtime *runtime = substream->runtime;
  92         struct imx_pcm_runtime_data *iprtd = runtime->private_data;
  93         struct pt_regs regs;
  94
  95         get_fiq_regs(&regs);
  96         if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK)
  97                 regs.ARM_r8 = (iprtd->period * iprtd->periods - 1) << 16;
  98         else
  99                 regs.ARM_r9 = (iprtd->period * iprtd->periods - 1) << 16;
 100
 101         set_fiq_regs(&regs);
 102
 103         return 0;
 104 }
 105
 106 static int imx_pcm_fiq;
 107
 108 static int snd_imx_pcm_trigger(struct snd_soc_component *component,
 109                                struct snd_pcm_substream *substream, int cmd)
 110 {
 111         struct snd_pcm_runtime *runtime = substream->runtime;
 112         struct imx_pcm_runtime_data *iprtd = runtime->private_data;
 113
 114         switch (cmd) {
 115         case SNDRV_PCM_TRIGGER_START:
 116         case SNDRV_PCM_TRIGGER_RESUME:
 117         case SNDRV_PCM_TRIGGER_PAUSE_RELEASE:
 118                 if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK)
 119                         atomic_set(&iprtd->playing, 1);
 120                 else
 121                         atomic_set(&iprtd->capturing, 1);
 122                 hrtimer_start(&iprtd->hrt, ns_to_ktime(iprtd->poll_time_ns),
 123                       HRTIMER_MODE_REL);
 124                 enable_fiq(imx_pcm_fiq);
 125                 break;
 126
 127         case SNDRV_PCM_TRIGGER_STOP:
 128         case SNDRV_PCM_TRIGGER_SUSPEND:
 129         case SNDRV_PCM_TRIGGER_PAUSE_PUSH:
 130                 if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK)
 131                         atomic_set(&iprtd->playing, 0);
 132                 else
 133                         atomic_set(&iprtd->capturing, 0);
 134                 if (!atomic_read(&iprtd->playing) &&
 135                                 !atomic_read(&iprtd->capturing))
 136                         disable_fiq(imx_pcm_fiq);
 137                 break;
 138
 139         default:
 140                 return -EINVAL;
 141         }
 142
 143         return 0;
 144 }
 145
 146 static snd_pcm_uframes_t
 147 snd_imx_pcm_pointer(struct snd_soc_component *component,
 148                     struct snd_pcm_substream *substream)
 149 {
 150         struct snd_pcm_runtime *runtime = substream->runtime;
 151         struct imx_pcm_runtime_data *iprtd = runtime->private_data;
 152
 153         return bytes_to_frames(substream->runtime, iprtd->offset);
 154 }
 155
 156 static const struct snd_pcm_hardware snd_imx_hardware = {
 157         .info = SNDRV_PCM_INFO_INTERLEAVED |
 158                 SNDRV_PCM_INFO_BLOCK_TRANSFER |
 159                 SNDRV_PCM_INFO_MMAP |
 160                 SNDRV_PCM_INFO_MMAP_VALID |
 161                 SNDRV_PCM_INFO_PAUSE |
 162                 SNDRV_PCM_INFO_RESUME,
 163         .formats = SNDRV_PCM_FMTBIT_S16_LE,
 164         .buffer_bytes_max = IMX_SSI_DMABUF_SIZE,
 165         .period_bytes_min = 128,
 166         .period_bytes_max = 16 * 1024,
 167         .periods_min = 4,
 168         .periods_max = 255,
 169         .fifo_size = 0,
 170 };
 171
 172 static int snd_imx_open(struct snd_soc_component *component,
 173                         struct snd_pcm_substream *substream)
 174 {
 175         struct snd_pcm_runtime *runtime = substream->runtime;
 176         struct imx_pcm_runtime_data *iprtd;
 177         int ret;
 178
 179         iprtd = kzalloc(sizeof(*iprtd), GFP_KERNEL);
 180         if (iprtd == NULL)
 181                 return -ENOMEM;
 182         runtime->private_data = iprtd;
 183
 184         iprtd->substream = substream;
 185
 186         atomic_set(&iprtd->playing, 0);
 187         atomic_set(&iprtd->capturing, 0);
 188         hrtimer_init(&iprtd->hrt, CLOCK_MONOTONIC, HRTIMER_MODE_REL);
 189         iprtd->hrt.function = snd_hrtimer_callback;
 190
 191         ret = snd_pcm_hw_constraint_integer(substream->runtime,
 192                         SNDRV_PCM_HW_PARAM_PERIODS);
 193         if (ret < 0) {
 194                 kfree(iprtd);
 195                 return ret;
 196         }
 197
 198         snd_soc_set_runtime_hwparams(substream, &snd_imx_hardware);
 199         return 0;
 200 }
 201
 202 static int snd_imx_close(struct snd_soc_component *component,
 203                          struct snd_pcm_substream *substream)
 204 {
 205         struct snd_pcm_runtime *runtime = substream->runtime;
 206         struct imx_pcm_runtime_data *iprtd = runtime->private_data;
 207
 208         hrtimer_cancel(&iprtd->hrt);
 209
 210         kfree(iprtd);
 211
 212         return 0;
 213 }
 214
 215 static int imx_pcm_new(struct snd_soc_pcm_runtime *rtd)
 216 {
 217         struct snd_card *card = rtd->card->snd_card;
 218         struct snd_pcm *pcm = rtd->pcm;
 219         int ret;
 220
 221         ret = dma_coerce_mask_and_coherent(card->dev, DMA_BIT_MASK(32));
 222         if (ret)
 223                 return ret;
 224
 225         return snd_pcm_set_fixed_buffer_all(pcm, SNDRV_DMA_TYPE_DEV_WC,
 226                                             pcm->card->dev,
 227                                             IMX_SSI_DMABUF_SIZE);
 228 }
 229
 230 static int ssi_irq;
 231
 232 static int snd_imx_pcm_new(struct snd_soc_component *component,
 233                            struct snd_soc_pcm_runtime *rtd)
 234 {
 235         struct snd_pcm *pcm = rtd->pcm;
 236         struct snd_pcm_substream *substream;
 237         int ret;
 238
 239         ret = imx_pcm_new(rtd);
 240         if (ret)
 241                 return ret;
 242
 243         substream = pcm->streams[SNDRV_PCM_STREAM_PLAYBACK].substream;
 244         if (substream) {
 245                 struct snd_dma_buffer *buf = &substream->dma_buffer;
 246
 247                 imx_ssi_fiq_tx_buffer = (unsigned long)buf->area;
 248         }
 249
 250         substream = pcm->streams[SNDRV_PCM_STREAM_CAPTURE].substream;
 251         if (substream) {
 252                 struct snd_dma_buffer *buf = &substream->dma_buffer;
 253
 254                 imx_ssi_fiq_rx_buffer = (unsigned long)buf->area;
 255         }
 256
 257         set_fiq_handler(&imx_ssi_fiq_start,
 258                 &imx_ssi_fiq_end - &imx_ssi_fiq_start);
 259
 260         return 0;
 261 }
 262
 263 static void snd_imx_pcm_free(struct snd_soc_component *component,
 264                              struct snd_pcm *pcm)
 265 {
 266         mxc_set_irq_fiq(ssi_irq, 0);
 267         release_fiq(&fh);
 268 }
 269
 270 static const struct snd_soc_component_driver imx_soc_component_fiq = {
 271         .open           = snd_imx_open,
 272         .close          = snd_imx_close,
 273         .hw_params      = snd_imx_pcm_hw_params,
 274         .prepare        = snd_imx_pcm_prepare,
 275         .trigger        = snd_imx_pcm_trigger,
 276         .pointer        = snd_imx_pcm_pointer,
 277         .pcm_construct  = snd_imx_pcm_new,
 278         .pcm_destruct   = snd_imx_pcm_free,
 279 };
 280
 281 int imx_pcm_fiq_init(struct platform_device *pdev,
 282                 struct imx_pcm_fiq_params *params)
 283 {
 284         int ret;
 285
 286         ret = claim_fiq(&fh);
 287         if (ret) {
 288                 dev_err(&pdev->dev, "failed to claim fiq: %d", ret);
 289                 return ret;
 290         }
 291
 292         mxc_set_irq_fiq(params->irq, 1);
 293         ssi_irq = params->irq;
 294
 295         imx_pcm_fiq = params->irq;
 296
 297         imx_ssi_fiq_base = (unsigned long)params->base;
 298
 299         params->dma_params_tx->maxburst = 4;
 300         params->dma_params_rx->maxburst = 6;
 301
 302         ret = devm_snd_soc_register_component(&pdev->dev, &imx_soc_component_fiq,
 303                                               NULL, 0);
 304         if (ret)
 305                 goto failed_register;
 306
 307         return 0;
 308
 309 failed_register:
 310         mxc_set_irq_fiq(ssi_irq, 0);
 311         release_fiq(&fh);
 312
 313         return ret;
 314 }
 315 EXPORT_SYMBOL_GPL(imx_pcm_fiq_init);
 316
 317 void imx_pcm_fiq_exit(struct platform_device *pdev)
 318 {
 319 }
 320 EXPORT_SYMBOL_GPL(imx_pcm_fiq_exit);
 321
 322 MODULE_DESCRIPTION("Freescale i.MX PCM FIQ handler");
 323 MODULE_LICENSE("GPL");