diff options
Diffstat (limited to 'sound/soc/at91/at91-pcm.c')
-rw-r--r-- | sound/soc/at91/at91-pcm.c | 432 |
1 files changed, 432 insertions, 0 deletions
diff --git a/sound/soc/at91/at91-pcm.c b/sound/soc/at91/at91-pcm.c new file mode 100644 index 000000000000..e88b12e7cc40 --- /dev/null +++ b/sound/soc/at91/at91-pcm.c @@ -0,0 +1,432 @@ +/* + * at91-pcm.c -- ALSA PCM interface for the Atmel AT91 SoC + * + * Author: Frank Mandarino <fmandarino@endrelia.com> + * Endrelia Technologies Inc. + * Created: Mar 3, 2006 + * + * Based on pxa2xx-pcm.c by: + * + * 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/platform_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 <sound/soc.h> + +#include <asm/arch/hardware.h> +#include <asm/arch/at91_ssc.h> +#include <asm/arch/at91_pdc.h> + +#include "at91-pcm.h" + +#if 0 +#define DBG(x...) printk(KERN_INFO "at91-pcm: " x) +#else +#define DBG(x...) +#endif + +static const struct snd_pcm_hardware at91_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, + .periods_min = 2, + .periods_max = 1024, + .buffer_bytes_max = 32 * 1024, +}; + +struct at91_runtime_data { + struct at91_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 */ + u32 pdc_xpr_save; /* PDC register save */ + u32 pdc_xcr_save; + u32 pdc_xnpr_save; + u32 pdc_xncr_save; +}; + +static void at91_pcm_dma_irq(u32 ssc_sr, + struct snd_pcm_substream *substream) +{ + struct at91_runtime_data *prtd = substream->runtime->private_data; + struct at91_pcm_dma_params *params = prtd->params; + static int count = 0; + + count++; + + if (ssc_sr & params->mask->ssc_endbuf) { + + printk(KERN_WARNING + "at91-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 */ + at91_ssc_write(params->ssc_base + AT91_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; + } + + at91_ssc_write(params->ssc_base + params->pdc->xpr, prtd->period_ptr); + at91_ssc_write(params->ssc_base + params->pdc->xcr, + prtd->period_size / params->pdc_xfer_size); + + at91_ssc_write(params->ssc_base + AT91_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; + } + at91_ssc_write(params->ssc_base + params->pdc->xnpr, prtd->period_ptr); + at91_ssc_write(params->ssc_base + params->pdc->xncr, + prtd->period_size / params->pdc_xfer_size); + } + + snd_pcm_period_elapsed(substream); +} + +static int at91_pcm_hw_params(struct snd_pcm_substream *substream, + struct snd_pcm_hw_params *params) +{ + struct snd_pcm_runtime *runtime = substream->runtime; + struct at91_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 = at91_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); + + DBG("hw_params: DMA for %s initialized (dma_bytes=%d, period_size=%d)\n", + prtd->params->name, runtime->dma_bytes, prtd->period_size); + return 0; +} + +static int at91_pcm_hw_free(struct snd_pcm_substream *substream) +{ + struct at91_runtime_data *prtd = substream->runtime->private_data; + struct at91_pcm_dma_params *params = prtd->params; + + if (params != NULL) { + at91_ssc_write(params->ssc_base + AT91_PDC_PTCR, params->mask->pdc_disable); + prtd->params->dma_intr_handler = NULL; + } + + return 0; +} + +static int at91_pcm_prepare(struct snd_pcm_substream *substream) +{ + struct at91_runtime_data *prtd = substream->runtime->private_data; + struct at91_pcm_dma_params *params = prtd->params; + + at91_ssc_write(params->ssc_base + AT91_SSC_IDR, + params->mask->ssc_endx | params->mask->ssc_endbuf); + + at91_ssc_write(params->ssc_base + AT91_PDC_PTCR, params->mask->pdc_disable); + return 0; +} + +static int at91_pcm_trigger(struct snd_pcm_substream *substream, + int cmd) +{ + struct at91_runtime_data *prtd = substream->runtime->private_data; + struct at91_pcm_dma_params *params = prtd->params; + int ret = 0; + + switch (cmd) { + case SNDRV_PCM_TRIGGER_START: + prtd->period_ptr = prtd->dma_buffer; + + at91_ssc_write(params->ssc_base + params->pdc->xpr, prtd->period_ptr); + at91_ssc_write(params->ssc_base + params->pdc->xcr, + prtd->period_size / params->pdc_xfer_size); + + prtd->period_ptr += prtd->period_size; + at91_ssc_write(params->ssc_base + params->pdc->xnpr, prtd->period_ptr); + at91_ssc_write(params->ssc_base + params->pdc->xncr, + prtd->period_size / params->pdc_xfer_size); + + DBG("trigger: period_ptr=%lx, xpr=%lx, xcr=%ld, xnpr=%lx, xncr=%ld\n", + (unsigned long) prtd->period_ptr, + at91_ssc_read(params->ssc_base + params->pdc->xpr), + at91_ssc_read(params->ssc_base + params->pdc->xcr), + at91_ssc_read(params->ssc_base + params->pdc->xnpr), + at91_ssc_read(params->ssc_base + params->pdc->xncr)); + + at91_ssc_write(params->ssc_base + AT91_SSC_IER, + params->mask->ssc_endx | params->mask->ssc_endbuf); + + at91_ssc_write(params->ssc_base + AT91_PDC_PTCR, params->mask->pdc_enable); + + DBG("sr=%lx imr=%lx\n", at91_ssc_read(params->ssc_base + AT91_SSC_SR), + at91_ssc_read(params->ssc_base + AT91_SSC_IER)); + break; + + case SNDRV_PCM_TRIGGER_STOP: + case SNDRV_PCM_TRIGGER_SUSPEND: + case SNDRV_PCM_TRIGGER_PAUSE_PUSH: + at91_ssc_write(params->ssc_base + AT91_PDC_PTCR, params->mask->pdc_disable); + break; + + case SNDRV_PCM_TRIGGER_RESUME: + case SNDRV_PCM_TRIGGER_PAUSE_RELEASE: + at91_ssc_write(params->ssc_base + AT91_PDC_PTCR, params->mask->pdc_enable); + break; + + default: + ret = -EINVAL; + } + + return ret; +} + +static snd_pcm_uframes_t at91_pcm_pointer( + struct snd_pcm_substream *substream) +{ + struct snd_pcm_runtime *runtime = substream->runtime; + struct at91_runtime_data *prtd = runtime->private_data; + struct at91_pcm_dma_params *params = prtd->params; + dma_addr_t ptr; + snd_pcm_uframes_t x; + + ptr = (dma_addr_t) at91_ssc_read(params->ssc_base + params->pdc->xpr); + x = bytes_to_frames(runtime, ptr - prtd->dma_buffer); + + if (x == runtime->buffer_size) + x = 0; + return x; +} + +static int at91_pcm_open(struct snd_pcm_substream *substream) +{ + struct snd_pcm_runtime *runtime = substream->runtime; + struct at91_runtime_data *prtd; + int ret = 0; + + snd_soc_set_runtime_hwparams(substream, &at91_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(struct at91_runtime_data), GFP_KERNEL); + if (prtd == NULL) { + ret = -ENOMEM; + goto out; + } + runtime->private_data = prtd; + + out: + return ret; +} + +static int at91_pcm_close(struct snd_pcm_substream *substream) +{ + struct at91_runtime_data *prtd = substream->runtime->private_data; + + kfree(prtd); + return 0; +} + +static int at91_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 at91_pcm_ops = { + .open = at91_pcm_open, + .close = at91_pcm_close, + .ioctl = snd_pcm_lib_ioctl, + .hw_params = at91_pcm_hw_params, + .hw_free = at91_pcm_hw_free, + .prepare = at91_pcm_prepare, + .trigger = at91_pcm_trigger, + .pointer = at91_pcm_pointer, + .mmap = at91_pcm_mmap, +}; + +static int at91_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 = at91_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); + + DBG("preallocate_dma_buffer: area=%p, addr=%p, size=%d\n", + (void *) buf->area, + (void *) buf->addr, + size); + + if (!buf->area) + return -ENOMEM; + + buf->bytes = size; + return 0; +} + +static u64 at91_pcm_dmamask = 0xffffffff; + +static int at91_pcm_new(struct snd_card *card, + struct snd_soc_codec_dai *dai, struct snd_pcm *pcm) +{ + int ret = 0; + + if (!card->dev->dma_mask) + card->dev->dma_mask = &at91_pcm_dmamask; + if (!card->dev->coherent_dma_mask) + card->dev->coherent_dma_mask = 0xffffffff; + + if (dai->playback.channels_min) { + ret = at91_pcm_preallocate_dma_buffer(pcm, + SNDRV_PCM_STREAM_PLAYBACK); + if (ret) + goto out; + } + + if (dai->capture.channels_min) { + ret = at91_pcm_preallocate_dma_buffer(pcm, + SNDRV_PCM_STREAM_CAPTURE); + if (ret) + goto out; + } + out: + return ret; +} + +static void at91_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; + } +} + +#ifdef CONFIG_PM +static int at91_pcm_suspend(struct platform_device *pdev, + struct snd_soc_cpu_dai *dai) +{ + struct snd_pcm_runtime *runtime = dai->runtime; + struct at91_runtime_data *prtd; + struct at91_pcm_dma_params *params; + + if (!runtime) + return 0; + + prtd = runtime->private_data; + params = prtd->params; + + /* disable the PDC and save the PDC registers */ + + at91_ssc_write(params->ssc_base + AT91_PDC_PTCR, params->mask->pdc_disable); + + prtd->pdc_xpr_save = at91_ssc_read(params->ssc_base + params->pdc->xpr); + prtd->pdc_xcr_save = at91_ssc_read(params->ssc_base + params->pdc->xcr); + prtd->pdc_xnpr_save = at91_ssc_read(params->ssc_base + params->pdc->xnpr); + prtd->pdc_xncr_save = at91_ssc_read(params->ssc_base + params->pdc->xncr); + + return 0; +} + +static int at91_pcm_resume(struct platform_device *pdev, + struct snd_soc_cpu_dai *dai) +{ + struct snd_pcm_runtime *runtime = dai->runtime; + struct at91_runtime_data *prtd; + struct at91_pcm_dma_params *params; + + if (!runtime) + return 0; + + prtd = runtime->private_data; + params = prtd->params; + + /* restore the PDC registers and enable the PDC */ + at91_ssc_write(params->ssc_base + params->pdc->xpr, prtd->pdc_xpr_save); + at91_ssc_write(params->ssc_base + params->pdc->xcr, prtd->pdc_xcr_save); + at91_ssc_write(params->ssc_base + params->pdc->xnpr, prtd->pdc_xnpr_save); + at91_ssc_write(params->ssc_base + params->pdc->xncr, prtd->pdc_xncr_save); + + at91_ssc_write(params->ssc_base + AT91_PDC_PTCR, params->mask->pdc_enable); + return 0; +} +#else +#define at91_pcm_suspend NULL +#define at91_pcm_resume NULL +#endif + +struct snd_soc_platform at91_soc_platform = { + .name = "at91-audio", + .pcm_ops = &at91_pcm_ops, + .pcm_new = at91_pcm_new, + .pcm_free = at91_pcm_free_dma_buffers, + .suspend = at91_pcm_suspend, + .resume = at91_pcm_resume, +}; + +EXPORT_SYMBOL_GPL(at91_soc_platform); + +MODULE_AUTHOR("Frank Mandarino <fmandarino@endrelia.com>"); +MODULE_DESCRIPTION("Atmel AT91 PCM module"); +MODULE_LICENSE("GPL"); |