linux-4.4.1/dmaengine_pcm_new() の変更点

• 追加された行はこの色です。
• 削除された行はこの色です。
• linux-4.4.1/dmaengine_pcm_new() へ行く。
• linux-4.4.1/dmaengine_pcm_new() の差分を削除

*参照元 [#v86277ee]
#backlinks

*説明 [#o171c679]
-パス: [[linux-4.4.1/sound/soc/soc-generic-dmaengine-pcm.c]]

-FIXME: これは何？
--説明


**引数 [#m076f081]
-struct snd_soc_pcm_runtime *rtd
--
--[[linux-4.4.1/snd_soc_pcm_runtime]]


**返り値 [#w1ed46e3]
-int
--


**参考 [#p8a75663]


*実装 [#k6b8b773]
 static int dmaengine_pcm_new(struct snd_soc_pcm_runtime *rtd)
 {
         struct dmaengine_pcm *pcm = soc_platform_to_pcm(rtd->platform);
         const struct snd_dmaengine_pcm_config *config = pcm->config;
         struct device *dev = rtd->platform->dev;
         struct snd_dmaengine_dai_dma_data *dma_data;
         struct snd_pcm_substream *substream;
         size_t prealloc_buffer_size;
         size_t max_buffer_size;
         unsigned int i;
         int ret;
 
-
--[[linux-4.4.1/dmaengine_pcm]]
--[[linux-4.4.1/soc_platform_to_pcm()]]
--[[linux-4.4.1/snd_dmaengine_pcm_config]]
--[[linux-4.4.1/device]]
--[[linux-4.4.1/snd_dmaengine_dai_dma_data]]
--[[linux-4.4.1/snd_pcm_substream]]

         if (config && config->prealloc_buffer_size) {
                 prealloc_buffer_size = config->prealloc_buffer_size;
                 max_buffer_size = config->pcm_hardware->buffer_bytes_max;
         } else {
                 prealloc_buffer_size = 512 * 1024;
                 max_buffer_size = SIZE_MAX;
         }
 
 
-
--config->pcm_hardware は const struct snd_pcm_hardware * 型
--[[linux-4.4.1/snd_pcm_hardware]]

         for (i = SNDRV_PCM_STREAM_PLAYBACK; i <= SNDRV_PCM_STREAM_CAPTURE; i++) {
                 substream = rtd->pcm->streams[i].substream;
                 if (!substream)
                         continue;
 
-
--rtd->pcm は  型
--rtd->pcm->streams は  型
--[[linux-4.4.1/]]
--rtd->pcm は struct snd_pcm * 型
--rtd->pcm->streams は struct snd_pcm_str[2] 型
--[[linux-4.4.1/snd_pcm]]
--[[linux-4.4.1/snd_pcm_str]]

                 dma_data = snd_soc_dai_get_dma_data(rtd->cpu_dai, substream);
 
-
--[[linux-4.4.1/snd_soc_dai_get_dma_data()]]

                 if (!pcm->chan[i] &&
                     (pcm->flags & SND_DMAENGINE_PCM_FLAG_CUSTOM_CHANNEL_NAME))
                         pcm->chan[i] = dma_request_slave_channel(dev,
                                 dma_data->chan_name);
 
-
--[[linux-4.4.1/dma_request_slave_channel()]]

                 if (!pcm->chan[i] && (pcm->flags & SND_DMAENGINE_PCM_FLAG_COMPAT)) {
                         pcm->chan[i] = dmaengine_pcm_compat_request_channel(rtd,
                                 substream);
                 }
 
-
--[[linux-4.4.1/dmaengine_pcm_compat_request_channel()]]

                 if (!pcm->chan[i]) {
                         dev_err(rtd->platform->dev,
                                 "Missing dma channel for stream: %d\n", i);
                         return -EINVAL;
                 }
 
-
--[[linux-4.4.1/dev_err()]]

                 ret = snd_pcm_lib_preallocate_pages(substream,
                                 SNDRV_DMA_TYPE_DEV_IRAM,
                                 dmaengine_dma_dev(pcm, substream),
                                 prealloc_buffer_size,
                                 max_buffer_size);
                 if (ret)
                         return ret;
 
-
--[[linux-4.4.1/snd_pcm_lib_preallocate_pages()]]
--[[linux-4.4.1/dmaengine_dma_dev()]]

                 if (!dmaengine_pcm_can_report_residue(dev, pcm->chan[i]))
                         pcm->flags |= SND_DMAENGINE_PCM_FLAG_NO_RESIDUE;
-
--[[linux-4.4.1/dmaengine_pcm_can_report_residue()]]

         }
 
         return 0;
 }


*コメント [#fbbad646]