--- /dev/null
+/*
+ * mx1_mx2-pcm.c -- ALSA SoC interface for Freescale i.MX1x, i.MX2x CPUs
+ *
+ * Copyright 2009 Vista Silicon S.L.
+ * Author: Javier Martin
+ * javier.martin@vista-silicon.com
+ *
+ * Based on mxc-pcm.c by Liam Girdwood.
+ *
+ * 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/platform_device.h>
+#include <linux/slab.h>
+#include <linux/dma-mapping.h>
+#include <sound/core.h>
+#include <sound/pcm.h>
+#include <sound/pcm_params.h>
+#include <sound/soc.h>
+#include <asm/dma.h>
+#include <mach/hardware.h>
+#include <mach/dma-mx1-mx2.h>
+
+#include "mx1_mx2-pcm.h"
+
+
+static const struct snd_pcm_hardware mx1_mx2_pcm_hardware = {
+ .info = (SNDRV_PCM_INFO_INTERLEAVED |
+ SNDRV_PCM_INFO_BLOCK_TRANSFER |
+ SNDRV_PCM_INFO_MMAP |
+ SNDRV_PCM_INFO_MMAP_VALID),
+ .formats = SNDRV_PCM_FMTBIT_S16_LE,
+ .buffer_bytes_max = 32 * 1024,
+ .period_bytes_min = 64,
+ .period_bytes_max = 8 * 1024,
+ .periods_min = 2,
+ .periods_max = 255,
+ .fifo_size = 0,
+};
+
+struct mx1_mx2_runtime_data {
+ int dma_ch;
+ int active;
+ unsigned int period;
+ unsigned int periods;
+ int tx_spin;
+ spinlock_t dma_lock;
+ struct mx1_mx2_pcm_dma_params *dma_params;
+};
+
+
+/**
+ * This function stops the current dma transfer for playback
+ * and clears the dma pointers.
+ *
+ * @param substream pointer to the structure of the current stream.
+ *
+ */
+static int audio_stop_dma(struct snd_pcm_substream *substream)
+{
+ struct snd_pcm_runtime *runtime = substream->runtime;
+ struct mx1_mx2_runtime_data *prtd = runtime->private_data;
+ unsigned long flags;
+
+ spin_lock_irqsave(&prtd->dma_lock, flags);
+
+ pr_debug("%s\n", __func__);
+
+ prtd->active = 0;
+ prtd->period = 0;
+ prtd->periods = 0;
+
+ /* this stops the dma channel and clears the buffer ptrs */
+
+ imx_dma_disable(prtd->dma_ch);
+
+ spin_unlock_irqrestore(&prtd->dma_lock, flags);
+
+ return 0;
+}
+
+/**
+ * This function is called whenever a new audio block needs to be
+ * transferred to the codec. The function receives the address and the size
+ * of the new block and start a new DMA transfer.
+ *
+ * @param substream pointer to the structure of the current stream.
+ *
+ */
+static int dma_new_period(struct snd_pcm_substream *substream)
+{
+ struct snd_pcm_runtime *runtime = substream->runtime;
+ struct mx1_mx2_runtime_data *prtd = runtime->private_data;
+ unsigned int dma_size;
+ unsigned int offset;
+ int ret = 0;
+ dma_addr_t mem_addr;
+ unsigned int dev_addr;
+
+ if (prtd->active) {
+ dma_size = frames_to_bytes(runtime, runtime->period_size);
+ offset = dma_size * prtd->period;
+
+ pr_debug("%s: period (%d) out of (%d)\n", __func__,
+ prtd->period,
+ runtime->periods);
+ pr_debug("period_size %d frames\n offset %d bytes\n",
+ (unsigned int)runtime->period_size,
+ offset);
+ pr_debug("dma_size %d bytes\n", dma_size);
+
+ snd_BUG_ON(dma_size > mx1_mx2_pcm_hardware.period_bytes_max);
+
+ mem_addr = (dma_addr_t)(runtime->dma_addr + offset);
+ dev_addr = prtd->dma_params->per_address;
+ pr_debug("%s: mem_addr is %x\n dev_addr is %x\n",
+ __func__, mem_addr, dev_addr);
+
+ ret = imx_dma_setup_single(prtd->dma_ch, mem_addr,
+ dma_size, dev_addr,
+ prtd->dma_params->transfer_type);
+ if (ret < 0) {
+ printk(KERN_ERR "Error configuring DMA\n");
+ return ret;
+ }
+ imx_dma_enable(prtd->dma_ch);
+
+ pr_debug("%s: transfer enabled\nmem_addr = %x\n",
+ __func__, (unsigned int) mem_addr);
+ pr_debug("dev_addr = %x\ndma_size = %d\n",
+ (unsigned int) dev_addr, dma_size);
+
+ prtd->tx_spin = 1; /* FGA little trick to retrieve DMA pos */
+ prtd->period++;
+ prtd->period %= runtime->periods;
+ }
+ return ret;
+}
+
+
+/**
+ * This is a callback which will be called
+ * when a TX transfer finishes. The call occurs
+ * in interrupt context.
+ *
+ * @param dat pointer to the structure of the current stream.
+ *
+ */
+static void audio_dma_irq(int channel, void *data)
+{
+ struct snd_pcm_substream *substream;
+ struct snd_pcm_runtime *runtime;
+ struct mx1_mx2_runtime_data *prtd;
+ unsigned int dma_size;
+ unsigned int previous_period;
+ unsigned int offset;
+
+ substream = data;
+ runtime = substream->runtime;
+ prtd = runtime->private_data;
+ previous_period = prtd->periods;
+ dma_size = frames_to_bytes(runtime, runtime->period_size);
+ offset = dma_size * previous_period;
+
+ prtd->tx_spin = 0;
+ prtd->periods++;
+ prtd->periods %= runtime->periods;
+
+ pr_debug("%s: irq per %d offset %x\n", __func__, prtd->periods, offset);
+
+ /*
+ * If we are getting a callback for an active stream then we inform
+ * the PCM middle layer we've finished a period
+ */
+ if (prtd->active)
+ snd_pcm_period_elapsed(substream);
+
+ /*
+ * Trig next DMA transfer
+ */
+ dma_new_period(substream);
+}
+
+/**
+ * This function configures the hardware to allow audio
+ * playback operations. It is called by ALSA framework.
+ *
+ * @param substream pointer to the structure of the current stream.
+ *
+ * @return 0 on success, -1 otherwise.
+ */
+static int
+snd_mx1_mx2_prepare(struct snd_pcm_substream *substream)
+{
+ struct snd_pcm_runtime *runtime = substream->runtime;
+ struct mx1_mx2_runtime_data *prtd = runtime->private_data;
+
+ prtd->period = 0;
+ prtd->periods = 0;
+
+ return 0;
+}
+
+static int mx1_mx2_pcm_hw_params(struct snd_pcm_substream *substream,
+ struct snd_pcm_hw_params *hw_params)
+{
+ struct snd_pcm_runtime *runtime = substream->runtime;
+ int ret;
+
+ ret = snd_pcm_lib_malloc_pages(substream,
+ params_buffer_bytes(hw_params));
+ if (ret < 0) {
+ printk(KERN_ERR "%s: failed to malloc pcm pages\n", __func__);
+ return ret;
+ }
+
+ pr_debug("%s: snd_imx1_mx2_audio_hw_params runtime->dma_addr 0x(%x)\n",
+ __func__, (unsigned int)runtime->dma_addr);
+ pr_debug("%s: snd_imx1_mx2_audio_hw_params runtime->dma_area 0x(%x)\n",
+ __func__, (unsigned int)runtime->dma_area);
+ pr_debug("%s: snd_imx1_mx2_audio_hw_params runtime->dma_bytes 0x(%x)\n",
+ __func__, (unsigned int)runtime->dma_bytes);
+
+ return ret;
+}
+
+static int mx1_mx2_pcm_hw_free(struct snd_pcm_substream *substream)
+{
+ struct snd_pcm_runtime *runtime = substream->runtime;
+ struct mx1_mx2_runtime_data *prtd = runtime->private_data;
+
+ imx_dma_free(prtd->dma_ch);
+
+ snd_pcm_lib_free_pages(substream);
+
+ return 0;
+}
+
+static int mx1_mx2_pcm_trigger(struct snd_pcm_substream *substream, int cmd)
+{
+ struct mx1_mx2_runtime_data *prtd = substream->runtime->private_data;
+ int ret = 0;
+
+ switch (cmd) {
+ case SNDRV_PCM_TRIGGER_START:
+ prtd->tx_spin = 0;
+ /* requested stream startup */
+ prtd->active = 1;
+ pr_debug("%s: starting dma_new_period\n", __func__);
+ ret = dma_new_period(substream);
+ break;
+ case SNDRV_PCM_TRIGGER_STOP:
+ /* requested stream shutdown */
+ pr_debug("%s: stopping dma transfer\n", __func__);
+ ret = audio_stop_dma(substream);
+ break;
+ default:
+ ret = -EINVAL;
+ break;
+ }
+
+ return ret;
+}
+
+static snd_pcm_uframes_t
+mx1_mx2_pcm_pointer(struct snd_pcm_substream *substream)
+{
+ struct snd_pcm_runtime *runtime = substream->runtime;
+ struct mx1_mx2_runtime_data *prtd = runtime->private_data;
+ unsigned int offset = 0;
+
+ /* tx_spin value is used here to check if a transfer is active */
+ if (prtd->tx_spin) {
+ offset = (runtime->period_size * (prtd->periods)) +
+ (runtime->period_size >> 1);
+ if (offset >= runtime->buffer_size)
+ offset = runtime->period_size >> 1;
+ } else {
+ offset = (runtime->period_size * (prtd->periods));
+ if (offset >= runtime->buffer_size)
+ offset = 0;
+ }
+ pr_debug("%s: pointer offset %x\n", __func__, offset);
+
+ return offset;
+}
+
+static int mx1_mx2_pcm_open(struct snd_pcm_substream *substream)
+{
+ struct snd_pcm_runtime *runtime = substream->runtime;
+ struct mx1_mx2_runtime_data *prtd;
+ struct snd_soc_pcm_runtime *rtd = substream->private_data;
+ struct mx1_mx2_pcm_dma_params *dma_data = rtd->dai->cpu_dai->dma_data;
+ int ret;
+
+ snd_soc_set_runtime_hwparams(substream, &mx1_mx2_pcm_hardware);
+
+ ret = snd_pcm_hw_constraint_integer(runtime,
+ SNDRV_PCM_HW_PARAM_PERIODS);
+ if (ret < 0)
+ return ret;
+
+ prtd = kzalloc(sizeof(struct mx1_mx2_runtime_data), GFP_KERNEL);
+ if (prtd == NULL) {
+ ret = -ENOMEM;
+ goto out;
+ }
+
+ runtime->private_data = prtd;
+
+ if (!dma_data)
+ return -ENODEV;
+
+ prtd->dma_params = dma_data;
+
+ pr_debug("%s: Requesting dma channel (%s)\n", __func__,
+ prtd->dma_params->name);
+ prtd->dma_ch = imx_dma_request_by_prio(prtd->dma_params->name,
+ DMA_PRIO_HIGH);
+ if (prtd->dma_ch < 0) {
+ printk(KERN_ERR "Error requesting dma channel\n");
+ return ret;
+ }
+ imx_dma_config_burstlen(prtd->dma_ch,
+ prtd->dma_params->watermark_level);
+
+ ret = imx_dma_config_channel(prtd->dma_ch,
+ prtd->dma_params->per_config,
+ prtd->dma_params->mem_config,
+ prtd->dma_params->event_id, 0);
+
+ if (ret) {
+ pr_debug(KERN_ERR "Error configuring dma channel %d\n",
+ prtd->dma_ch);
+ return ret;
+ }
+
+ pr_debug("%s: Setting tx dma callback function\n", __func__);
+ ret = imx_dma_setup_handlers(prtd->dma_ch,
+ audio_dma_irq, NULL,
+ (void *)substream);
+ if (ret < 0) {
+ printk(KERN_ERR "Error setting dma callback function\n");
+ return ret;
+ }
+ return 0;
+
+ out:
+ return ret;
+}
+
+static int mx1_mx2_pcm_close(struct snd_pcm_substream *substream)
+{
+ struct snd_pcm_runtime *runtime = substream->runtime;
+ struct mx1_mx2_runtime_data *prtd = runtime->private_data;
+
+ kfree(prtd);
+
+ return 0;
+}
+
+static int mx1_mx2_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);
+}
+
+struct snd_pcm_ops mx1_mx2_pcm_ops = {
+ .open = mx1_mx2_pcm_open,
+ .close = mx1_mx2_pcm_close,
+ .ioctl = snd_pcm_lib_ioctl,
+ .hw_params = mx1_mx2_pcm_hw_params,
+ .hw_free = mx1_mx2_pcm_hw_free,
+ .prepare = snd_mx1_mx2_prepare,
+ .trigger = mx1_mx2_pcm_trigger,
+ .pointer = mx1_mx2_pcm_pointer,
+ .mmap = mx1_mx2_pcm_mmap,
+};
+
+static u64 mx1_mx2_pcm_dmamask = 0xffffffff;
+
+static int mx1_mx2_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 = mx1_mx2_pcm_hardware.buffer_bytes_max;
+ buf->dev.type = SNDRV_DMA_TYPE_DEV;
+ buf->dev.dev = pcm->card->dev;
+ buf->private_data = NULL;
+
+ /* Reserve uncached-buffered memory area for DMA */
+ buf->area = dma_alloc_writecombine(pcm->card->dev, size,
+ &buf->addr, GFP_KERNEL);
+
+ pr_debug("%s: preallocate_dma_buffer: area=%p, addr=%p, size=%d\n",
+ __func__, (void *) buf->area, (void *) buf->addr, size);
+
+ if (!buf->area)
+ return -ENOMEM;
+
+ buf->bytes = size;
+ return 0;
+}
+
+static void mx1_mx2_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;
+ }
+}
+
+int mx1_mx2_pcm_new(struct snd_card *card, struct snd_soc_dai *dai,
+ struct snd_pcm *pcm)
+{
+ int ret = 0;
+
+ if (!card->dev->dma_mask)
+ card->dev->dma_mask = &mx1_mx2_pcm_dmamask;
+ if (!card->dev->coherent_dma_mask)
+ card->dev->coherent_dma_mask = 0xffffffff;
+
+ if (dai->playback.channels_min) {
+ ret = mx1_mx2_pcm_preallocate_dma_buffer(pcm,
+ SNDRV_PCM_STREAM_PLAYBACK);
+ pr_debug("%s: preallocate playback buffer\n", __func__);
+ if (ret)
+ goto out;
+ }
+
+ if (dai->capture.channels_min) {
+ ret = mx1_mx2_pcm_preallocate_dma_buffer(pcm,
+ SNDRV_PCM_STREAM_CAPTURE);
+ pr_debug("%s: preallocate capture buffer\n", __func__);
+ if (ret)
+ goto out;
+ }
+ out:
+ return ret;
+}
+
+struct snd_soc_platform mx1_mx2_soc_platform = {
+ .name = "mx1_mx2-audio",
+ .pcm_ops = &mx1_mx2_pcm_ops,
+ .pcm_new = mx1_mx2_pcm_new,
+ .pcm_free = mx1_mx2_pcm_free_dma_buffers,
+};
+EXPORT_SYMBOL_GPL(mx1_mx2_soc_platform);
+
+static int __init mx1_mx2_soc_platform_init(void)
+{
+ return snd_soc_register_platform(&mx1_mx2_soc_platform);
+}
+module_init(mx1_mx2_soc_platform_init);
+
+static void __exit mx1_mx2_soc_platform_exit(void)
+{
+ snd_soc_unregister_platform(&mx1_mx2_soc_platform);
+}
+module_exit(mx1_mx2_soc_platform_exit);
+
+MODULE_AUTHOR("Javier Martin, javier.martin@vista-silicon.com");
+MODULE_DESCRIPTION("Freescale i.MX2x, i.MX1x PCM DMA module");
+MODULE_LICENSE("GPL");
projects / linux-2.6-microblaze.git / commitdiff