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;
> +	}