linux3.2.65中uda1341播放声音杂音与卡顿
我只做了linux3.2.65中的优化,主要修改的文件是sound/soc/samsung/dma.c 因为在linux2.6.32.65中uda134x播放声音正常,因此这里参考了linux2.6.32.65中
linux-2.6.32.64\sound\soc\s3c24xx\s3c24xx_pcm.c中有关DMA的部分,以下是linux3.2.55修改之后的源文件内容
</pre>另外更改本次的uda134x同时也参考了http://www.xuebuyuan.com/2150214.html</p><p>要使用uda134x需要在arch/arm/mach-s3c2440/mach-smdk2440.c中添加以下代码部分<pre name="code" class="objc">/* UDA1341 */static struct s3c24xx_uda134x_platform_data s3c24xx_uda134x_data = {.l3_clk = S3C2410_GPB(4),.l3_data = S3C2410_GPB(3),.l3_mode = S3C2410_GPB(2),.model = UDA134X_UDA1341,};static struct platform_device s3c_device_uda134x = {.name = "s3c24xx_uda134x",.dev = {.platform_data = &s3c24xx_uda134x_data,}};static struct platform_device s3c_device_uda134x_codec ={ .name = "uda134x-codec", .id = -1,};&s3c_device_uda134x_codec,&s3c_device_uda134x,&samsung_asoc_dma,
如果你的是3.2内核基本上可以原样copy否则的请参考linux2.6.32中的uda134x dma部分。
/* * dma.c -- ALSA Soc Audio Layer * * (c) 2006 Wolfson Microelectronics PLC. * Graeme Gregory graeme.gregory@wolfsonmicro.com or linux@wolfsonmicro.com * * Copyright 2004-2005 Simtec Electronics *http://armlinux.simtec.co.uk/ *Ben Dooks <ben@simtec.co.uk> * * This program is free software; you can redistribute it and/or modify it * under the terms of the GNU General Public License as published by the * Free Software Foundation; either version 2 of the License, or (at your * option) any later version. */#include <linux/slab.h>#include <linux/dma-mapping.h>#include <linux/module.h>#include <sound/soc.h>#include <sound/pcm_params.h>#include <asm/dma.h>#include <mach/hardware.h>#include <mach/dma.h>#include "dma.h"#define ST_RUNNING(1<<0)#define ST_OPENED(1<<1)enum s3c2410_dmasrc {S3C2410_DMASRC_HW,/* source is memory */S3C2410_DMASRC_MEM/* source is hardware */};static const struct snd_pcm_hardware dma_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 | SNDRV_PCM_FMTBIT_U16_LE | SNDRV_PCM_FMTBIT_U8 | SNDRV_PCM_FMTBIT_S8,.channels_min= 2,.channels_max= 2,.buffer_bytes_max= 128*1024,.period_bytes_min= PAGE_SIZE,.period_bytes_max= PAGE_SIZE*2,.periods_min= 2,.periods_max= 128,.fifo_size= 32,};struct runtime_data {spinlock_t lock;int state;unsigned int dma_loaded;unsigned int dma_limit;unsigned int dma_period;dma_addr_t dma_start;dma_addr_t dma_pos;dma_addr_t dma_end;struct s3c_dma_params *params;};//static void audio_buffdone(void *data);/* dma_enqueue * * place a dma buffer onto the queue for the dma system * to handle. */static void dma_enqueue(struct snd_pcm_substream *substream){ struct runtime_data *prtd = substream->runtime->private_data; dma_addr_t pos = prtd->dma_pos; unsigned int limit; int ret; pr_debug("Entered%s\n", __func__); if (samsung_dma_has_circular()) { limit = (prtd->dma_end - prtd->dma_start) / prtd->dma_period; } else limit = prtd->dma_limit; pr_debug("%s:loaded %d, limit %d\n", __func__,prtd->dma_loaded, limit); while(prtd->dma_loaded < limit) { unsigned long len = prtd->dma_period; pr_debug("dma_loaded:%d\n", prtd->dma_loaded); if ((pos + len) > prtd->dma_end) { len = prtd->dma_end - pos; pr_debug(KERN_DEBUG "%s: corrected dma len %ld\n", __func__, len); } ret = s3c2410_dma_enqueue(prtd->params->channel, substream,pos,len); if(ret == 0){ prtd->dma_loaded++; pos+= prtd->dma_period; if(pos>=prtd->dma_end) pos= prtd->dma_start; }else break; } prtd->dma_pos= pos;}static void audio_buffdone(struct s3c2410_dma_chan *channel,void *dev_id, int size,enum s3c2410_dma_buffresult result){struct snd_pcm_substream *substream = dev_id;struct runtime_data *prtd;pr_debug("Entered %s\n", __func__);if (result == S3C2410_RES_ABORT || result == S3C2410_RES_ERR)return;prtd = substream->runtime->private_data;if (substream)snd_pcm_period_elapsed(substream);spin_lock(&prtd->lock);if (prtd->state & ST_RUNNING && !samsung_dma_has_circular()) {prtd->dma_loaded--;dma_enqueue(substream);}spin_unlock(&prtd->lock);}static int dma_hw_params(struct snd_pcm_substream *substream,struct snd_pcm_hw_params *params){struct snd_pcm_runtime *runtime = substream->runtime;struct runtime_data *prtd = runtime->private_data;struct snd_soc_pcm_runtime *rtd = substream->private_data;unsigned long totbytes = params_buffer_bytes(params);struct s3c_dma_params *dma =snd_soc_dai_get_dma_data(rtd->cpu_dai, substream);int ret = 0;pr_debug("Entered %s\n", __func__);/* return if this is a bufferless transfer e.g. * codec <--> BT codec or GSM modem -- lg FIXME */if (!dma)return 0;/* this may get called several times by oss emulation * with different params -HW */if (prtd->params == NULL) {/* prepare DMA */prtd->params = dma;pr_debug("params %p, client %p, channel %d\n", prtd->params,prtd->params->client, prtd->params->channel);ret = s3c2410_dma_request(prtd->params->channel, prtd->params->client, NULL);if (ret < 0) {printk(KERN_ERR "failed to get dma channel\n");return ret;}/* use the circular buffering if we have it available. */if (samsung_dma_has_circular())s3c2410_dma_setflags(prtd->params->channel, S3C2410_DMAF_CIRCULAR);}s3c2410_dma_set_buffdone_fn(prtd->params->channel, audio_buffdone);snd_pcm_set_runtime_buffer(substream, &substream->dma_buffer);runtime->dma_bytes = totbytes;spin_lock_irq(&prtd->lock);prtd->dma_loaded = 0;prtd->dma_limit = runtime->hw.periods_min;prtd->dma_period = params_period_bytes(params);prtd->dma_start = runtime->dma_addr;prtd->dma_pos = prtd->dma_start;prtd->dma_end = prtd->dma_start + totbytes;spin_unlock_irq(&prtd->lock);return 0;}static int dma_hw_free(struct snd_pcm_substream *substream){struct runtime_data *prtd = substream->runtime->private_data;pr_debug("Entered %s\n", __func__);snd_pcm_set_runtime_buffer(substream, NULL);if (prtd->params) {s3c2410_dma_free(prtd->params->channel, prtd->params->client);prtd->params = NULL;}return 0;}static int dma_prepare(struct snd_pcm_substream *substream){struct runtime_data *prtd = substream->runtime->private_data;int ret = 0;pr_debug("Entered %s\n", __func__);/* return if this is a bufferless transfer e.g. * codec <--> BT codec or GSM modem -- lg FIXME */if (!prtd->params)return 0;/* channel needs configuring for mem=>device, increment memory addr, * sync to pclk, half-word transfers to the IIS-FIFO. */if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK) {s3c2410_dma_devconfig(prtd->params->channel, S3C2410_DMASRC_MEM, prtd->params->dma_addr);} else {s3c2410_dma_devconfig(prtd->params->channel, S3C2410_DMASRC_HW, prtd->params->dma_addr);}s3c2410_dma_config(prtd->params->channel, prtd->params->dma_size);/* flush the DMA channel */s3c2410_dma_ctrl(prtd->params->channel, S3C2410_DMAOP_FLUSH);prtd->dma_loaded = 0;prtd->dma_pos = prtd->dma_start;/* enqueue dma buffers */dma_enqueue(substream);return ret;}static int dma_trigger(struct snd_pcm_substream *substream, int cmd){struct runtime_data *prtd = substream->runtime->private_data;int ret = 0;pr_debug("Entered %s\n", __func__);spin_lock(&prtd->lock);switch (cmd) {case SNDRV_PCM_TRIGGER_START:case SNDRV_PCM_TRIGGER_RESUME:case SNDRV_PCM_TRIGGER_PAUSE_RELEASE:prtd->state |= ST_RUNNING;s3c2410_dma_ctrl(prtd->params->channel, S3C2410_DMAOP_START);break;case SNDRV_PCM_TRIGGER_STOP:case SNDRV_PCM_TRIGGER_SUSPEND:case SNDRV_PCM_TRIGGER_PAUSE_PUSH:prtd->state &= ~ST_RUNNING;s3c2410_dma_ctrl(prtd->params->channel, S3C2410_DMAOP_STOP);break;default:ret = -EINVAL;break;}spin_unlock(&prtd->lock);return ret;}static snd_pcm_uframes_tdma_pointer(struct snd_pcm_substream *substream){struct snd_pcm_runtime *runtime = substream->runtime;struct runtime_data *prtd = runtime->private_data;unsigned long res;dma_addr_t src, dst;pr_debug("Entered %s\n", __func__);spin_lock(&prtd->lock);s3c2410_dma_getposition(prtd->params->channel, &src, &dst);if (substream->stream == SNDRV_PCM_STREAM_CAPTURE)res = dst - prtd->dma_start;elseres = src - prtd->dma_start;spin_unlock(&prtd->lock);pr_debug("Pointer %x %x\n", src, dst);/* we seem to be getting the odd error from the pcm library due * to out-of-bounds pointers. this is maybe due to the dma engine * not having loaded the new values for the channel before being * callled... (todo - fix ) */if (res >= snd_pcm_lib_buffer_bytes(substream)) {if (res == snd_pcm_lib_buffer_bytes(substream))res = 0;}return bytes_to_frames(substream->runtime, res);}static int dma_open(struct snd_pcm_substream *substream){struct snd_pcm_runtime *runtime = substream->runtime;struct runtime_data *prtd;pr_debug("Entered %s\n", __func__);snd_pcm_hw_constraint_integer(runtime, SNDRV_PCM_HW_PARAM_PERIODS);snd_soc_set_runtime_hwparams(substream, &dma_hardware);prtd = kzalloc(sizeof(struct runtime_data), GFP_KERNEL);if (prtd == NULL)return -ENOMEM;spin_lock_init(&prtd->lock);runtime->private_data = prtd;return 0;}static int dma_close(struct snd_pcm_substream *substream){struct snd_pcm_runtime *runtime = substream->runtime;struct runtime_data *prtd = runtime->private_data;pr_debug("Entered %s\n", __func__);if (!prtd)pr_debug("dma_close called with prtd == NULL\n");kfree(prtd);return 0;}static int dma_mmap(struct snd_pcm_substream *substream,struct vm_area_struct *vma){struct snd_pcm_runtime *runtime = substream->runtime;pr_debug("Entered %s\n", __func__);return dma_mmap_writecombine(substream->pcm->card->dev, vma, runtime->dma_area, runtime->dma_addr, runtime->dma_bytes);}static struct snd_pcm_ops dma_ops = {.open= dma_open,.close= dma_close,.ioctl= snd_pcm_lib_ioctl,.hw_params= dma_hw_params,.hw_free= dma_hw_free,.prepare= dma_prepare,.trigger= dma_trigger,.pointer= dma_pointer,.mmap= dma_mmap,};static int 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 = dma_hardware.buffer_bytes_max;pr_debug("Entered %s\n", __func__);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 dma_free_dma_buffers(struct snd_pcm *pcm){struct snd_pcm_substream *substream;struct snd_dma_buffer *buf;int stream;pr_debug("Entered %s\n", __func__);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 dma_mask = DMA_BIT_MASK(32);static int dma_new(struct snd_soc_pcm_runtime *rtd){struct snd_card *card = rtd->card->snd_card;struct snd_soc_dai *dai = rtd->cpu_dai;struct snd_pcm *pcm = rtd->pcm;int ret = 0;pr_debug("Entered %s\n", __func__);if (!card->dev->dma_mask)card->dev->dma_mask = &dma_mask;if (!card->dev->coherent_dma_mask)card->dev->coherent_dma_mask = 0xffffffff;if (dai->driver->playback.channels_min) {ret = preallocate_dma_buffer(pcm,SNDRV_PCM_STREAM_PLAYBACK);if (ret)goto out;}if (dai->driver->capture.channels_min) {ret = preallocate_dma_buffer(pcm,SNDRV_PCM_STREAM_CAPTURE);if (ret)goto out;}out:return ret;}static struct snd_soc_platform_driver samsung_asoc_platform = {.ops= &dma_ops,.pcm_new= dma_new,.pcm_free= dma_free_dma_buffers,};static int __devinit samsung_asoc_platform_probe(struct platform_device *pdev){return snd_soc_register_platform(&pdev->dev, &samsung_asoc_platform);}static int __devexit samsung_asoc_platform_remove(struct platform_device *pdev){snd_soc_unregister_platform(&pdev->dev);return 0;}static struct platform_driver asoc_dma_driver = {.driver = {.name = "samsung-audio",.owner = THIS_MODULE,},.probe = samsung_asoc_platform_probe,.remove = __devexit_p(samsung_asoc_platform_remove),};static int __init samsung_asoc_init(void){return platform_driver_register(&asoc_dma_driver);}module_init(samsung_asoc_init);static void __exit samsung_asoc_exit(void){platform_driver_unregister(&asoc_dma_driver);}module_exit(samsung_asoc_exit);MODULE_AUTHOR("Ben Dooks, <ben@simtec.co.uk>");MODULE_DESCRIPTION("Samsung ASoC DMA Driver");MODULE_LICENSE("GPL");MODULE_ALIAS("platform:samsung-audio");
一个人身边的位置只有这么多，
