| /* |
| * 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"); |