--- /dev/null
+/*
+ * linux/sound/arm/pxa2xx-pcm.c -- ALSA PCM interface for the Intel PXA2xx chip
+ *
+ * Author: Nicolas Pitre
+ * Created: Nov 30, 2004
+ * Copyright: (C) 2004 MontaVista Software, Inc.
+ *
+ * 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/init.h>
+#include <linux/device.h>
+#include <linux/slab.h>
+#include <linux/dma-mapping.h>
+
+#include <sound/driver.h>
+#include <sound/core.h>
+#include <sound/pcm.h>
+#include <sound/pcm_params.h>
+
+#include <asm/dma.h>
+#include <asm/hardware.h>
+#include <asm/arch/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,
+ .formats = SNDRV_PCM_FMTBIT_S16_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,
+};
+
+struct pxa2xx_runtime_data {
+ int dma_ch;
+ struct pxa2xx_pcm_dma_params *params;
+ pxa_dma_desc *dma_desc_array;
+ dma_addr_t dma_desc_array_phys;
+};
+
+static 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;
+}
+
+static int pxa2xx_pcm_hw_free(struct snd_pcm_substream *substream)
+{
+ struct pxa2xx_runtime_data *rtd = substream->runtime->private_data;
+
+ *rtd->params->drcmr = 0;
+ snd_pcm_set_runtime_buffer(substream, NULL);
+ return 0;
+}
+
+static int pxa2xx_pcm_prepare(struct snd_pcm_substream *substream)
+{
+ struct pxa2xx_pcm_client *client = substream->private_data;
+ struct snd_pcm_runtime *runtime = substream->runtime;
+ struct pxa2xx_runtime_data *rtd = runtime->private_data;
+
+ DCSR(rtd->dma_ch) &= ~DCSR_RUN;
+ DCSR(rtd->dma_ch) = 0;
+ DCMD(rtd->dma_ch) = 0;
+ *rtd->params->drcmr = rtd->dma_ch | DRCMR_MAPVLD;
+
+ return client->prepare(substream);
+}
+
+static int pxa2xx_pcm_trigger(struct snd_pcm_substream *substream, int cmd)
+{
+ struct pxa2xx_runtime_data *rtd = substream->runtime->private_data;
+ int ret = 0;
+
+ switch (cmd) {
+ case SNDRV_PCM_TRIGGER_START:
+ DDADR(rtd->dma_ch) = rtd->dma_desc_array_phys;
+ DCSR(rtd->dma_ch) = DCSR_RUN;
+ break;
+
+ case SNDRV_PCM_TRIGGER_STOP:
+ case SNDRV_PCM_TRIGGER_SUSPEND:
+ case SNDRV_PCM_TRIGGER_PAUSE_PUSH:
+ DCSR(rtd->dma_ch) &= ~DCSR_RUN;
+ break;
+
+ case SNDRV_PCM_TRIGGER_PAUSE_RELEASE:
+ DCSR(rtd->dma_ch) |= DCSR_RUN;
+ break;
+
+ default:
+ ret = -EINVAL;
+ }
+
+ return ret;
+}
+
+static void pxa2xx_pcm_dma_irq(int dma_ch, void *dev_id, struct pt_regs *regs)
+{
+ 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);
+ }
+}
+
+static snd_pcm_uframes_t pxa2xx_pcm_pointer(struct snd_pcm_substream *substream)
+{
+ struct snd_pcm_runtime *runtime = substream->runtime;
+ struct pxa2xx_runtime_data *rtd = runtime->private_data;
+ dma_addr_t ptr = (substream->stream == SNDRV_PCM_STREAM_PLAYBACK) ?
+ DSADR(rtd->dma_ch) : DTADR(rtd->dma_ch);
+ snd_pcm_uframes_t x = bytes_to_frames(runtime, ptr - runtime->dma_addr);
+ if (x == runtime->buffer_size)
+ x = 0;
+ return x;
+}
+
+static int
+pxa2xx_pcm_hw_rule_mult32(struct snd_pcm_hw_params *params, struct snd_pcm_hw_rule *rule)
+{
+ struct snd_interval *i = hw_param_interval(params, rule->var);
+ int changed = 0;
+
+ if (i->min & 31) {
+ i->min = (i->min & ~31) + 32;
+ i->openmin = 0;
+ changed = 1;
+ }
+
+ if (i->max & 31) {
+ i->max &= ~31;
+ i->openmax = 0;
+ changed = 1;
+ }
+
+ return changed;
+}
+
+static int pxa2xx_pcm_open(struct snd_pcm_substream *substream)
+{
+ struct pxa2xx_pcm_client *client = substream->private_data;
+ 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_rule_add(runtime, 0, SNDRV_PCM_HW_PARAM_PERIOD_BYTES,
+ pxa2xx_pcm_hw_rule_mult32, NULL,
+ SNDRV_PCM_HW_PARAM_PERIOD_BYTES, -1);
+ if (ret)
+ goto out;
+ ret = snd_pcm_hw_rule_add(runtime, 0, SNDRV_PCM_HW_PARAM_BUFFER_BYTES,
+ pxa2xx_pcm_hw_rule_mult32, NULL,
+ SNDRV_PCM_HW_PARAM_BUFFER_BYTES, -1);
+ if (ret)
+ 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;
+
+ rtd->params = (substream->stream == SNDRV_PCM_STREAM_PLAYBACK) ?
+ client->playback_params : client->capture_params;
+ ret = pxa_request_dma(rtd->params->name, DMA_PRIO_LOW,
+ pxa2xx_pcm_dma_irq, substream);
+ if (ret < 0)
+ goto err2;
+ rtd->dma_ch = ret;
+
+ runtime->private_data = rtd;
+ ret = client->startup(substream);
+ if (!ret)
+ goto out;
+
+ pxa_free_dma(rtd->dma_ch);
+ err2:
+ dma_free_writecombine(substream->pcm->card->dev, PAGE_SIZE,
+ rtd->dma_desc_array, rtd->dma_desc_array_phys);
+ err1:
+ kfree(rtd);
+ out:
+ return ret;
+}
+
+static int pxa2xx_pcm_close(struct snd_pcm_substream *substream)
+{
+ struct pxa2xx_pcm_client *client = substream->private_data;
+ struct pxa2xx_runtime_data *rtd = substream->runtime->private_data;
+
+ pxa_free_dma(rtd->dma_ch);
+ client->shutdown(substream);
+ dma_free_writecombine(substream->pcm->card->dev, PAGE_SIZE,
+ rtd->dma_desc_array, rtd->dma_desc_array_phys);
+ kfree(rtd);
+ return 0;
+}
+
+static 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);
+}
+
+static struct snd_pcm_ops pxa2xx_pcm_ops = {
+ .open = pxa2xx_pcm_open,
+ .close = pxa2xx_pcm_close,
+ .ioctl = snd_pcm_lib_ioctl,
+ .hw_params = pxa2xx_pcm_hw_params,
+ .hw_free = pxa2xx_pcm_hw_free,
+ .prepare = pxa2xx_pcm_prepare,
+ .trigger = pxa2xx_pcm_trigger,
+ .pointer = pxa2xx_pcm_pointer,
+ .mmap = pxa2xx_pcm_mmap,
+};
+
+static 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;
+}
+
+static 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;
+ }
+}
+
+static u64 pxa2xx_pcm_dmamask = 0xffffffff;
+
+int pxa2xx_pcm_new(struct snd_card *card, struct pxa2xx_pcm_client *client,
+ struct snd_pcm **rpcm)
+{
+ struct snd_pcm *pcm;
+ int play = client->playback_params ? 1 : 0;
+ int capt = client->capture_params ? 1 : 0;
+ int ret;
+
+ ret = snd_pcm_new(card, "PXA2xx-PCM", 0, play, capt, &pcm);
+ if (ret)
+ goto out;
+
+ pcm->private_data = client;
+ pcm->private_free = pxa2xx_pcm_free_dma_buffers;
+
+ if (!card->dev->dma_mask)
+ card->dev->dma_mask = &pxa2xx_pcm_dmamask;
+ if (!card->dev->coherent_dma_mask)
+ card->dev->coherent_dma_mask = 0xffffffff;
+
+ if (play) {
+ int stream = SNDRV_PCM_STREAM_PLAYBACK;
+ snd_pcm_set_ops(pcm, stream, &pxa2xx_pcm_ops);
+ ret = pxa2xx_pcm_preallocate_dma_buffer(pcm, stream);
+ if (ret)
+ goto out;
+ }
+ if (capt) {
+ int stream = SNDRV_PCM_STREAM_CAPTURE;
+ snd_pcm_set_ops(pcm, stream, &pxa2xx_pcm_ops);
+ ret = pxa2xx_pcm_preallocate_dma_buffer(pcm, stream);
+ if (ret)
+ goto out;
+ }
+
+ if (rpcm)
+ *rpcm = pcm;
+ ret = 0;
+
+ out:
+ return ret;
+}
+
+EXPORT_SYMBOL(pxa2xx_pcm_new);
+
+MODULE_AUTHOR("Nicolas Pitre");
+MODULE_DESCRIPTION("Intel PXA2xx PCM DMA module");
+MODULE_LICENSE("GPL");
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