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-rw-r--r--sound/soc/at32/at32-pcm.c492
1 files changed, 492 insertions, 0 deletions
diff --git a/sound/soc/at32/at32-pcm.c b/sound/soc/at32/at32-pcm.c
new file mode 100644
index 0000000..c83584f
--- /dev/null
+++ b/sound/soc/at32/at32-pcm.c
@@ -0,0 +1,492 @@
+/* sound/soc/at32/at32-pcm.c
+ * ASoC PCM interface for Atmel AT32 SoC
+ *
+ * Copyright (C) 2008 Long Range Systems
+ * Geoffrey Wossum <gwossum@acm.org>
+ *
+ * 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.
+ *
+ * Note that this is basically a port of the sound/soc/at91-pcm.c to
+ * the AVR32 kernel. Thanks to Frank Mandarino for that code.
+ */
+
+#include <linux/module.h>
+#include <linux/init.h>
+#include <linux/platform_device.h>
+#include <linux/slab.h>
+#include <linux/dma-mapping.h>
+#include <linux/atmel_pdc.h>
+
+#include <sound/core.h>
+#include <sound/pcm.h>
+#include <sound/pcm_params.h>
+#include <sound/soc.h>
+
+#include "at32-pcm.h"
+
+
+
+/*--------------------------------------------------------------------------*\
+ * Hardware definition
+\*--------------------------------------------------------------------------*/
+/* TODO: These values were taken from the AT91 platform driver, check
+ * them against real values for AT32
+ */
+static const struct snd_pcm_hardware at32_pcm_hardware = {
+ .info = (SNDRV_PCM_INFO_MMAP |
+ SNDRV_PCM_INFO_MMAP_VALID |
+ SNDRV_PCM_INFO_INTERLEAVED |
+ SNDRV_PCM_INFO_BLOCK_TRANSFER |
+ SNDRV_PCM_INFO_PAUSE),
+
+ .formats = SNDRV_PCM_FMTBIT_S16,
+ .period_bytes_min = 32,
+ .period_bytes_max = 8192, /* 512 frames * 16 bytes / frame */
+ .periods_min = 2,
+ .periods_max = 1024,
+ .buffer_bytes_max = 32 * 1024,
+};
+
+
+
+/*--------------------------------------------------------------------------*\
+ * Data types
+\*--------------------------------------------------------------------------*/
+struct at32_runtime_data {
+ struct at32_pcm_dma_params *params;
+ dma_addr_t dma_buffer; /* physical address of DMA buffer */
+ dma_addr_t dma_buffer_end; /* first address beyond DMA buffer */
+ size_t period_size;
+
+ dma_addr_t period_ptr; /* physical address of next period */
+ int periods; /* period index of period_ptr */
+
+ /* Save PDC registers (for power management) */
+ u32 pdc_xpr_save;
+ u32 pdc_xcr_save;
+ u32 pdc_xnpr_save;
+ u32 pdc_xncr_save;
+};
+
+
+
+/*--------------------------------------------------------------------------*\
+ * Helper functions
+\*--------------------------------------------------------------------------*/
+static int at32_pcm_preallocate_dma_buffer(struct snd_pcm *pcm, int stream)
+{
+ struct snd_pcm_substream *substream = pcm->streams[stream].substream;
+ struct snd_dma_buffer *dmabuf = &substream->dma_buffer;
+ size_t size = at32_pcm_hardware.buffer_bytes_max;
+
+ dmabuf->dev.type = SNDRV_DMA_TYPE_DEV;
+ dmabuf->dev.dev = pcm->card->dev;
+ dmabuf->private_data = NULL;
+ dmabuf->area = dma_alloc_coherent(pcm->card->dev, size,
+ &dmabuf->addr, GFP_KERNEL);
+ pr_debug("at32_pcm: preallocate_dma_buffer: "
+ "area=%p, addr=%p, size=%ld\n",
+ (void *)dmabuf->area, (void *)dmabuf->addr, size);
+
+ if (!dmabuf->area)
+ return -ENOMEM;
+
+ dmabuf->bytes = size;
+ return 0;
+}
+
+
+
+/*--------------------------------------------------------------------------*\
+ * ISR
+\*--------------------------------------------------------------------------*/
+static void at32_pcm_dma_irq(u32 ssc_sr, struct snd_pcm_substream *substream)
+{
+ struct snd_pcm_runtime *rtd = substream->runtime;
+ struct at32_runtime_data *prtd = rtd->private_data;
+ struct at32_pcm_dma_params *params = prtd->params;
+ static int count;
+
+ count++;
+ if (ssc_sr & params->mask->ssc_endbuf) {
+ pr_warning("at32-pcm: buffer %s on %s (SSC_SR=%#x, count=%d)\n",
+ substream->stream == SNDRV_PCM_STREAM_PLAYBACK ?
+ "underrun" : "overrun", params->name, ssc_sr, count);
+
+ /* re-start the PDC */
+ ssc_writex(params->ssc->regs, ATMEL_PDC_PTCR,
+ params->mask->pdc_disable);
+ prtd->period_ptr += prtd->period_size;
+ if (prtd->period_ptr >= prtd->dma_buffer_end)
+ prtd->period_ptr = prtd->dma_buffer;
+
+
+ ssc_writex(params->ssc->regs, params->pdc->xpr,
+ prtd->period_ptr);
+ ssc_writex(params->ssc->regs, params->pdc->xcr,
+ prtd->period_size / params->pdc_xfer_size);
+ ssc_writex(params->ssc->regs, ATMEL_PDC_PTCR,
+ params->mask->pdc_enable);
+ }
+
+
+ if (ssc_sr & params->mask->ssc_endx) {
+ /* Load the PDC next pointer and counter registers */
+ prtd->period_ptr += prtd->period_size;
+ if (prtd->period_ptr >= prtd->dma_buffer_end)
+ prtd->period_ptr = prtd->dma_buffer;
+ ssc_writex(params->ssc->regs, params->pdc->xnpr,
+ prtd->period_ptr);
+ ssc_writex(params->ssc->regs, params->pdc->xncr,
+ prtd->period_size / params->pdc_xfer_size);
+ }
+
+
+ snd_pcm_period_elapsed(substream);
+}
+
+
+
+/*--------------------------------------------------------------------------*\
+ * PCM operations
+\*--------------------------------------------------------------------------*/
+static int at32_pcm_hw_params(struct snd_pcm_substream *substream,
+ struct snd_pcm_hw_params *params)
+{
+ struct snd_pcm_runtime *runtime = substream->runtime;
+ struct at32_runtime_data *prtd = runtime->private_data;
+ struct snd_soc_pcm_runtime *rtd = substream->private_data;
+
+ /* this may get called several times by oss emulation
+ * with different params
+ */
+ snd_pcm_set_runtime_buffer(substream, &substream->dma_buffer);
+ runtime->dma_bytes = params_buffer_bytes(params);
+
+ prtd->params = rtd->dai->cpu_dai->dma_data;
+ prtd->params->dma_intr_handler = at32_pcm_dma_irq;
+
+ prtd->dma_buffer = runtime->dma_addr;
+ prtd->dma_buffer_end = runtime->dma_addr + runtime->dma_bytes;
+ prtd->period_size = params_period_bytes(params);
+
+ pr_debug("hw_params: DMA for %s initialized "
+ "(dma_bytes=%ld, period_size=%ld)\n",
+ prtd->params->name, runtime->dma_bytes, prtd->period_size);
+
+ return 0;
+}
+
+
+
+static int at32_pcm_hw_free(struct snd_pcm_substream *substream)
+{
+ struct at32_runtime_data *prtd = substream->runtime->private_data;
+ struct at32_pcm_dma_params *params = prtd->params;
+
+ if (params != NULL) {
+ ssc_writex(params->ssc->regs, SSC_PDC_PTCR,
+ params->mask->pdc_disable);
+ prtd->params->dma_intr_handler = NULL;
+ }
+
+ return 0;
+}
+
+
+
+static int at32_pcm_prepare(struct snd_pcm_substream *substream)
+{
+ struct at32_runtime_data *prtd = substream->runtime->private_data;
+ struct at32_pcm_dma_params *params = prtd->params;
+
+ ssc_writex(params->ssc->regs, SSC_IDR,
+ params->mask->ssc_endx | params->mask->ssc_endbuf);
+ ssc_writex(params->ssc->regs, ATMEL_PDC_PTCR,
+ params->mask->pdc_disable);
+
+ return 0;
+}
+
+
+static int at32_pcm_trigger(struct snd_pcm_substream *substream, int cmd)
+{
+ struct snd_pcm_runtime *rtd = substream->runtime;
+ struct at32_runtime_data *prtd = rtd->private_data;
+ struct at32_pcm_dma_params *params = prtd->params;
+ int ret = 0;
+
+ pr_debug("at32_pcm_trigger: buffer_size = %ld, "
+ "dma_area = %p, dma_bytes = %ld\n",
+ rtd->buffer_size, rtd->dma_area, rtd->dma_bytes);
+
+ switch (cmd) {
+ case SNDRV_PCM_TRIGGER_START:
+ prtd->period_ptr = prtd->dma_buffer;
+
+ ssc_writex(params->ssc->regs, params->pdc->xpr,
+ prtd->period_ptr);
+ ssc_writex(params->ssc->regs, params->pdc->xcr,
+ prtd->period_size / params->pdc_xfer_size);
+
+ prtd->period_ptr += prtd->period_size;
+ ssc_writex(params->ssc->regs, params->pdc->xnpr,
+ prtd->period_ptr);
+ ssc_writex(params->ssc->regs, params->pdc->xncr,
+ prtd->period_size / params->pdc_xfer_size);
+
+ pr_debug("trigger: period_ptr=%lx, xpr=%x, "
+ "xcr=%d, xnpr=%x, xncr=%d\n",
+ (unsigned long)prtd->period_ptr,
+ ssc_readx(params->ssc->regs, params->pdc->xpr),
+ ssc_readx(params->ssc->regs, params->pdc->xcr),
+ ssc_readx(params->ssc->regs, params->pdc->xnpr),
+ ssc_readx(params->ssc->regs, params->pdc->xncr));
+
+ ssc_writex(params->ssc->regs, SSC_IER,
+ params->mask->ssc_endx | params->mask->ssc_endbuf);
+ ssc_writex(params->ssc->regs, SSC_PDC_PTCR,
+ params->mask->pdc_enable);
+
+ pr_debug("sr=%x, imr=%x\n",
+ ssc_readx(params->ssc->regs, SSC_SR),
+ ssc_readx(params->ssc->regs, SSC_IER));
+ break; /* SNDRV_PCM_TRIGGER_START */
+
+
+
+ case SNDRV_PCM_TRIGGER_STOP:
+ case SNDRV_PCM_TRIGGER_SUSPEND:
+ case SNDRV_PCM_TRIGGER_PAUSE_PUSH:
+ ssc_writex(params->ssc->regs, ATMEL_PDC_PTCR,
+ params->mask->pdc_disable);
+ break;
+
+
+ case SNDRV_PCM_TRIGGER_RESUME:
+ case SNDRV_PCM_TRIGGER_PAUSE_RELEASE:
+ ssc_writex(params->ssc->regs, ATMEL_PDC_PTCR,
+ params->mask->pdc_enable);
+ break;
+
+ default:
+ ret = -EINVAL;
+ }
+
+ return ret;
+}
+
+
+
+static snd_pcm_uframes_t at32_pcm_pointer(struct snd_pcm_substream *substream)
+{
+ struct snd_pcm_runtime *runtime = substream->runtime;
+ struct at32_runtime_data *prtd = runtime->private_data;
+ struct at32_pcm_dma_params *params = prtd->params;
+ dma_addr_t ptr;
+ snd_pcm_uframes_t x;
+
+ ptr = (dma_addr_t) ssc_readx(params->ssc->regs, params->pdc->xpr);
+ x = bytes_to_frames(runtime, ptr - prtd->dma_buffer);
+
+ if (x == runtime->buffer_size)
+ x = 0;
+
+ return x;
+}
+
+
+
+static int at32_pcm_open(struct snd_pcm_substream *substream)
+{
+ struct snd_pcm_runtime *runtime = substream->runtime;
+ struct at32_runtime_data *prtd;
+ int ret = 0;
+
+ snd_soc_set_runtime_hwparams(substream, &at32_pcm_hardware);
+
+ /* ensure that buffer size is a multiple of period size */
+ ret = snd_pcm_hw_constraint_integer(runtime,
+ SNDRV_PCM_HW_PARAM_PERIODS);
+ if (ret < 0)
+ goto out;
+
+ prtd = kzalloc(sizeof(*prtd), GFP_KERNEL);
+ if (prtd == NULL) {
+ ret = -ENOMEM;
+ goto out;
+ }
+ runtime->private_data = prtd;
+
+
+out:
+ return ret;
+}
+
+
+
+static int at32_pcm_close(struct snd_pcm_substream *substream)
+{
+ struct at32_runtime_data *prtd = substream->runtime->private_data;
+
+ kfree(prtd);
+ return 0;
+}
+
+
+static int at32_pcm_mmap(struct snd_pcm_substream *substream,
+ struct vm_area_struct *vma)
+{
+ return remap_pfn_range(vma, vma->vm_start,
+ substream->dma_buffer.addr >> PAGE_SHIFT,
+ vma->vm_end - vma->vm_start, vma->vm_page_prot);
+}
+
+
+
+static struct snd_pcm_ops at32_pcm_ops = {
+ .open = at32_pcm_open,
+ .close = at32_pcm_close,
+ .ioctl = snd_pcm_lib_ioctl,
+ .hw_params = at32_pcm_hw_params,
+ .hw_free = at32_pcm_hw_free,
+ .prepare = at32_pcm_prepare,
+ .trigger = at32_pcm_trigger,
+ .pointer = at32_pcm_pointer,
+ .mmap = at32_pcm_mmap,
+};
+
+
+
+/*--------------------------------------------------------------------------*\
+ * ASoC platform driver
+\*--------------------------------------------------------------------------*/
+static u64 at32_pcm_dmamask = 0xffffffff;
+
+static int at32_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 = &at32_pcm_dmamask;
+ if (!card->dev->coherent_dma_mask)
+ card->dev->coherent_dma_mask = 0xffffffff;
+
+ if (dai->playback.channels_min) {
+ ret = at32_pcm_preallocate_dma_buffer(
+ pcm, SNDRV_PCM_STREAM_PLAYBACK);
+ if (ret)
+ goto out;
+ }
+
+ if (dai->capture.channels_min) {
+ pr_debug("at32-pcm: Allocating PCM capture DMA buffer\n");
+ ret = at32_pcm_preallocate_dma_buffer(
+ pcm, SNDRV_PCM_STREAM_CAPTURE);
+ if (ret)
+ goto out;
+ }
+
+
+out:
+ return ret;
+}
+
+
+
+static void at32_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 == NULL)
+ continue;
+
+ buf = &substream->dma_buffer;
+ if (!buf->area)
+ continue;
+ dma_free_coherent(pcm->card->dev, buf->bytes,
+ buf->area, buf->addr);
+ buf->area = NULL;
+ }
+}
+
+
+
+#ifdef CONFIG_PM
+static int at32_pcm_suspend(struct platform_device *pdev,
+ struct snd_soc_dai *dai)
+{
+ struct snd_pcm_runtime *runtime = dai->runtime;
+ struct at32_runtime_data *prtd;
+ struct at32_pcm_dma_params *params;
+
+ if (runtime == NULL)
+ return 0;
+ prtd = runtime->private_data;
+ params = prtd->params;
+
+ /* Disable the PDC and save the PDC registers */
+ ssc_writex(params->ssc->regs, ATMEL_PDC_PTCR,
+ params->mask->pdc_disable);
+
+ prtd->pdc_xpr_save = ssc_readx(params->ssc->regs, params->pdc->xpr);
+ prtd->pdc_xcr_save = ssc_readx(params->ssc->regs, params->pdc->xcr);
+ prtd->pdc_xnpr_save = ssc_readx(params->ssc->regs, params->pdc->xnpr);
+ prtd->pdc_xncr_save = ssc_readx(params->ssc->regs, params->pdc->xncr);
+
+ return 0;
+}
+
+
+
+static int at32_pcm_resume(struct platform_device *pdev,
+ struct snd_soc_dai *dai)
+{
+ struct snd_pcm_runtime *runtime = dai->runtime;
+ struct at32_runtime_data *prtd;
+ struct at32_pcm_dma_params *params;
+
+ if (runtime == NULL)
+ return 0;
+ prtd = runtime->private_data;
+ params = prtd->params;
+
+ /* Restore the PDC registers and enable the PDC */
+ ssc_writex(params->ssc->regs, params->pdc->xpr, prtd->pdc_xpr_save);
+ ssc_writex(params->ssc->regs, params->pdc->xcr, prtd->pdc_xcr_save);
+ ssc_writex(params->ssc->regs, params->pdc->xnpr, prtd->pdc_xnpr_save);
+ ssc_writex(params->ssc->regs, params->pdc->xncr, prtd->pdc_xncr_save);
+
+ ssc_writex(params->ssc->regs, ATMEL_PDC_PTCR, params->mask->pdc_enable);
+ return 0;
+}
+#else /* CONFIG_PM */
+# define at32_pcm_suspend NULL
+# define at32_pcm_resume NULL
+#endif /* CONFIG_PM */
+
+
+
+struct snd_soc_platform at32_soc_platform = {
+ .name = "at32-audio",
+ .pcm_ops = &at32_pcm_ops,
+ .pcm_new = at32_pcm_new,
+ .pcm_free = at32_pcm_free_dma_buffers,
+ .suspend = at32_pcm_suspend,
+ .resume = at32_pcm_resume,
+};
+EXPORT_SYMBOL_GPL(at32_soc_platform);
+
+
+
+MODULE_AUTHOR("Geoffrey Wossum <gwossum@acm.org>");
+MODULE_DESCRIPTION("Atmel AT32 PCM module");
+MODULE_LICENSE("GPL");
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