Re: [PATCH v2 9/9] ASoC: q6asm-dai: add support to copy callback

[Pierre-Louis Bossart]

+static int q6asm_compr_copy(struct snd_soc_component *component,
+                           struct snd_compr_stream *stream, char __user *buf,
+                           size_t count)
  {
        struct snd_compr_runtime *runtime = stream->runtime;
        struct q6asm_dai_rtd *prtd = runtime->private_data;
        unsigned long flags;
+       u32 wflags = 0;
+       int avail, bytes_in_flight = 0;
+       void *dstn;
+       size_t copy;
+       u32 app_pointer;
+       u32 bytes_received;
+
+       bytes_received = prtd->bytes_received;
+
+       /**

/*

+        * Make sure that next track data pointer is aligned at 32 bit boundary
+        * This is a Mandatory requirement from DSP data buffers alignment
+        */
+       if (prtd->next_track)
+               bytes_received = ALIGN(prtd->bytes_received, prtd->pcm_count);
+
+       app_pointer = bytes_received/prtd->pcm_size;
+       app_pointer = bytes_received -  (app_pointer * prtd->pcm_size);
+       dstn = prtd->dma_buffer.area + app_pointer;
+
+       if (count < prtd->pcm_size - app_pointer) {
+               if (copy_from_user(dstn, buf, count))
+                       return -EFAULT;
+       } else {
+               copy = prtd->pcm_size - app_pointer;
+               if (copy_from_user(dstn, buf, copy))
+                       return -EFAULT;
+               if (copy_from_user(prtd->dma_buffer.area, buf + copy,
+                                  count - copy))
+                       return -EFAULT;
+       }