[funini.com] -> [kei@sodan] -> Kernel Reading

root/sound/arm/pxa2xx-pcm-lib.c

/* [<][>][^][v][top][bottom][index][help] */

DEFINITIONS

This source file includes following definitions.
  1. __pxa2xx_pcm_hw_params
  2. __pxa2xx_pcm_hw_free
  3. pxa2xx_pcm_trigger
  4. pxa2xx_pcm_pointer
  5. __pxa2xx_pcm_prepare
  6. pxa2xx_pcm_dma_irq
  7. __pxa2xx_pcm_open
  8. __pxa2xx_pcm_close
  9. pxa2xx_pcm_mmap
  10. pxa2xx_pcm_preallocate_dma_buffer
  11. pxa2xx_pcm_free_dma_buffers

/*
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License version 2 as
 * published by the Free Software Foundation.
 */

#include <linux/module.h>
#include <linux/dma-mapping.h>

#include <sound/core.h>
#include <sound/pcm.h>
#include <sound/pcm_params.h>
#include <sound/pxa2xx-lib.h>

#include <asm/dma.h>
#include <mach/pxa-regs.h>

#include "pxa2xx-pcm.h"

static const struct snd_pcm_hardware pxa2xx_pcm_hardware = {
        .info                   = SNDRV_PCM_INFO_MMAP |
                                  SNDRV_PCM_INFO_MMAP_VALID |
                                  SNDRV_PCM_INFO_INTERLEAVED |
                                  SNDRV_PCM_INFO_PAUSE |
                                  SNDRV_PCM_INFO_RESUME,
        .formats                = SNDRV_PCM_FMTBIT_S16_LE |
                                        SNDRV_PCM_FMTBIT_S24_LE |
                                        SNDRV_PCM_FMTBIT_S32_LE,
        .period_bytes_min       = 32,
        .period_bytes_max       = 8192 - 32,
        .periods_min            = 1,
        .periods_max            = PAGE_SIZE/sizeof(pxa_dma_desc),
        .buffer_bytes_max       = 128 * 1024,
        .fifo_size              = 32,
};

int __pxa2xx_pcm_hw_params(struct snd_pcm_substream *substream,
                                struct snd_pcm_hw_params *params)
{
        struct snd_pcm_runtime *runtime = substream->runtime;
        struct pxa2xx_runtime_data *rtd = runtime->private_data;
        size_t totsize = params_buffer_bytes(params);
        size_t period = params_period_bytes(params);
        pxa_dma_desc *dma_desc;
        dma_addr_t dma_buff_phys, next_desc_phys;

        snd_pcm_set_runtime_buffer(substream, &substream->dma_buffer);
        runtime->dma_bytes = totsize;

        dma_desc = rtd->dma_desc_array;
        next_desc_phys = rtd->dma_desc_array_phys;
        dma_buff_phys = runtime->dma_addr;
        do {
                next_desc_phys += sizeof(pxa_dma_desc);
                dma_desc->ddadr = next_desc_phys;
                if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK) {
                        dma_desc->dsadr = dma_buff_phys;
                        dma_desc->dtadr = rtd->params->dev_addr;
                } else {
                        dma_desc->dsadr = rtd->params->dev_addr;
                        dma_desc->dtadr = dma_buff_phys;
                }
                if (period > totsize)
                        period = totsize;
                dma_desc->dcmd = rtd->params->dcmd | period | DCMD_ENDIRQEN;
                dma_desc++;
                dma_buff_phys += period;
        } while (totsize -= period);
        dma_desc[-1].ddadr = rtd->dma_desc_array_phys;

        return 0;
}
EXPORT_SYMBOL(__pxa2xx_pcm_hw_params);

int __pxa2xx_pcm_hw_free(struct snd_pcm_substream *substream)
{
        struct pxa2xx_runtime_data *rtd = substream->runtime->private_data;

        if (rtd && rtd->params)
                *rtd->params->drcmr = 0;

        snd_pcm_set_runtime_buffer(substream, NULL);
        return 0;
}
EXPORT_SYMBOL(__pxa2xx_pcm_hw_free);

int pxa2xx_pcm_trigger(struct snd_pcm_substream *substream, int cmd)
{
        struct pxa2xx_runtime_data *prtd = substream->runtime->private_data;
        int ret = 0;

        switch (cmd) {
        case SNDRV_PCM_TRIGGER_START:
                DDADR(prtd->dma_ch) = prtd->dma_desc_array_phys;
                DCSR(prtd->dma_ch) = DCSR_RUN;
                break;

        case SNDRV_PCM_TRIGGER_STOP:
        case SNDRV_PCM_TRIGGER_SUSPEND:
        case SNDRV_PCM_TRIGGER_PAUSE_PUSH:
                DCSR(prtd->dma_ch) &= ~DCSR_RUN;
                break;

        case SNDRV_PCM_TRIGGER_RESUME:
                DCSR(prtd->dma_ch) |= DCSR_RUN;
                break;
        case SNDRV_PCM_TRIGGER_PAUSE_RELEASE:
                DDADR(prtd->dma_ch) = prtd->dma_desc_array_phys;
                DCSR(prtd->dma_ch) |= DCSR_RUN;
                break;

        default:
                ret = -EINVAL;
        }

        return ret;
}
EXPORT_SYMBOL(pxa2xx_pcm_trigger);

snd_pcm_uframes_t
pxa2xx_pcm_pointer(struct snd_pcm_substream *substream)
{
        struct snd_pcm_runtime *runtime = substream->runtime;
        struct pxa2xx_runtime_data *prtd = runtime->private_data;

        dma_addr_t ptr = (substream->stream == SNDRV_PCM_STREAM_PLAYBACK) ?
                         DSADR(prtd->dma_ch) : DTADR(prtd->dma_ch);
        snd_pcm_uframes_t x = bytes_to_frames(runtime, ptr - runtime->dma_addr);

        if (x == runtime->buffer_size)
                x = 0;
        return x;
}
EXPORT_SYMBOL(pxa2xx_pcm_pointer);

int __pxa2xx_pcm_prepare(struct snd_pcm_substream *substream)
{
        struct pxa2xx_runtime_data *prtd = substream->runtime->private_data;

        DCSR(prtd->dma_ch) &= ~DCSR_RUN;
        DCSR(prtd->dma_ch) = 0;
        DCMD(prtd->dma_ch) = 0;
        *prtd->params->drcmr = prtd->dma_ch | DRCMR_MAPVLD;

        return 0;
}
EXPORT_SYMBOL(__pxa2xx_pcm_prepare);

void pxa2xx_pcm_dma_irq(int dma_ch, void *dev_id)
{
        struct snd_pcm_substream *substream = dev_id;
        struct pxa2xx_runtime_data *rtd = substream->runtime->private_data;
        int dcsr;

        dcsr = DCSR(dma_ch);
        DCSR(dma_ch) = dcsr & ~DCSR_STOPIRQEN;

        if (dcsr & DCSR_ENDINTR) {
                snd_pcm_period_elapsed(substream);
        } else {
                printk(KERN_ERR "%s: DMA error on channel %d (DCSR=%#x)\n",
                        rtd->params->name, dma_ch, dcsr);
                snd_pcm_stop(substream, SNDRV_PCM_STATE_XRUN);
        }
}
EXPORT_SYMBOL(pxa2xx_pcm_dma_irq);

int __pxa2xx_pcm_open(struct snd_pcm_substream *substream)
{
        struct snd_pcm_runtime *runtime = substream->runtime;
        struct pxa2xx_runtime_data *rtd;
        int ret;

        runtime->hw = pxa2xx_pcm_hardware;

        /*
         * For mysterious reasons (and despite what the manual says)
         * playback samples are lost if the DMA count is not a multiple
         * of the DMA burst size.  Let's add a rule to enforce that.
         */
        ret = snd_pcm_hw_constraint_step(runtime, 0,
                SNDRV_PCM_HW_PARAM_PERIOD_BYTES, 32);
        if (ret)
                goto out;

        ret = snd_pcm_hw_constraint_step(runtime, 0,
                SNDRV_PCM_HW_PARAM_BUFFER_BYTES, 32);
        if (ret)
                goto out;

        ret = snd_pcm_hw_constraint_integer(runtime,
                                            SNDRV_PCM_HW_PARAM_PERIODS);
        if (ret < 0)
                goto out;

        ret = -ENOMEM;
        rtd = kmalloc(sizeof(*rtd), GFP_KERNEL);
        if (!rtd)
                goto out;
        rtd->dma_desc_array =
                dma_alloc_writecombine(substream->pcm->card->dev, PAGE_SIZE,
                                       &rtd->dma_desc_array_phys, GFP_KERNEL);
        if (!rtd->dma_desc_array)
                goto err1;

        runtime->private_data = rtd;
        return 0;

 err1:
        kfree(rtd);
 out:
        return ret;
}
EXPORT_SYMBOL(__pxa2xx_pcm_open);

int __pxa2xx_pcm_close(struct snd_pcm_substream *substream)
{
        struct snd_pcm_runtime *runtime = substream->runtime;
        struct pxa2xx_runtime_data *rtd = runtime->private_data;

        dma_free_writecombine(substream->pcm->card->dev, PAGE_SIZE,
                              rtd->dma_desc_array, rtd->dma_desc_array_phys);
        kfree(rtd);
        return 0;
}
EXPORT_SYMBOL(__pxa2xx_pcm_close);

int pxa2xx_pcm_mmap(struct snd_pcm_substream *substream,
        struct vm_area_struct *vma)
{
        struct snd_pcm_runtime *runtime = substream->runtime;
        return dma_mmap_writecombine(substream->pcm->card->dev, vma,
                                     runtime->dma_area,
                                     runtime->dma_addr,
                                     runtime->dma_bytes);
}
EXPORT_SYMBOL(pxa2xx_pcm_mmap);

int pxa2xx_pcm_preallocate_dma_buffer(struct snd_pcm *pcm, int stream)
{
        struct snd_pcm_substream *substream = pcm->streams[stream].substream;
        struct snd_dma_buffer *buf = &substream->dma_buffer;
        size_t size = pxa2xx_pcm_hardware.buffer_bytes_max;
        buf->dev.type = SNDRV_DMA_TYPE_DEV;
        buf->dev.dev = pcm->card->dev;
        buf->private_data = NULL;
        buf->area = dma_alloc_writecombine(pcm->card->dev, size,
                                           &buf->addr, GFP_KERNEL);
        if (!buf->area)
                return -ENOMEM;
        buf->bytes = size;
        return 0;
}
EXPORT_SYMBOL(pxa2xx_pcm_preallocate_dma_buffer);

void pxa2xx_pcm_free_dma_buffers(struct snd_pcm *pcm)
{
        struct snd_pcm_substream *substream;
        struct snd_dma_buffer *buf;
        int stream;

        for (stream = 0; stream < 2; stream++) {
                substream = pcm->streams[stream].substream;
                if (!substream)
                        continue;
                buf = &substream->dma_buffer;
                if (!buf->area)
                        continue;
                dma_free_writecombine(pcm->card->dev, buf->bytes,
                                      buf->area, buf->addr);
                buf->area = NULL;
        }
}
EXPORT_SYMBOL(pxa2xx_pcm_free_dma_buffers);

MODULE_AUTHOR("Nicolas Pitre");
MODULE_DESCRIPTION("Intel PXA2xx sound library");
MODULE_LICENSE("GPL");

/* [<][>][^][v][top][bottom][index][help] */

[funini.com] -> [kei@sodan] -> Kernel Reading