[Sound-open-firmware] [PATCH 4/5] host: rename host_pos_read to host_pos_local and update comments

[Liam Girdwood]

On Wed, 2017-02-15 at 18:07 +0800, Keyon Jie wrote:
> We are using host_pos_read not only for playback, for capture,
> we use it as the host side buffer write pointer, so, here rename
> it to host_pos_local and add comments to explain that.
> 
> Signed-off-by: Keyon Jie <yang.jie at linux.intel.com>
> ---
>  src/audio/host.c | 48 ++++++++++++++++++++++++------------------------
>  1 file changed, 24 insertions(+), 24 deletions(-)
> 
> diff --git a/src/audio/host.c b/src/audio/host.c
> index 61d2b62..f814603 100644
> --- a/src/audio/host.c
> +++ b/src/audio/host.c
> @@ -71,11 +71,11 @@ struct host_data {
>  	struct hc_buf host;
>  	struct hc_buf local;
>  	uint32_t host_size;
> -	volatile uint32_t *host_pos;    /* read pos, update to mailbox for host side */
> -	uint32_t host_pos_read;         /* host buffer read pos in bytes */
> -	uint32_t host_period_bytes;	/* host period size in bytes */
> -	uint32_t host_period_pos;	/* position in current host perid */
> -	uint32_t host_app_pos;        /* host buffer app write pos, points to mailbox */
> +	volatile uint32_t *host_pos;    /* read/write pos, update to mailbox for host side */
> +	uint32_t host_pos_local;         /* the real host buffer local read/write pos in bytes */
> +	uint32_t host_period_bytes;	/* host period size(host_pos update period) in bytes */
> +	uint32_t host_period_pos;	/* position in current host period */
> +	uint32_t host_app_pos;        /* host buffer app write/read pos, udpate via IPC */

Why dont we just rename to use r_ptr and w_ptr naming, that makes it
very simple to understand. This way the copy() always updates read and
write ptrs without worrying about naming.

>  	uint32_t host_avail;   /* host buffer available size */
>  	uint32_t host_free;    /* host buffer free size */
>  	/* pointers set during params to host or local above */
> @@ -91,24 +91,24 @@ struct host_data {
>  
>  static inline void host_update_buffer_produce(struct host_data *hd)
>  {
> -	if (hd->host_pos_read < hd->host_app_pos)
> -		hd->host_avail = hd->host_app_pos - hd->host_pos_read;
> -	else if (hd->host_pos_read == hd->host_app_pos)
> +	if (hd->host_pos_local < hd->host_app_pos)
> +		hd->host_avail = hd->host_app_pos - hd->host_pos_local;
> +	else if (hd->host_pos_local == hd->host_app_pos)
>  		hd->host_avail = hd->host_size; /* full */
>  	else
> -		hd->host_avail = hd->host_size -hd->host_pos_read +
> +		hd->host_avail = hd->host_size -hd->host_pos_local +
>  			hd->host_app_pos;
>  	hd->host_free = hd->host_size - hd->host_avail;
>  }
>  
>  static inline void host_update_buffer_consume(struct host_data *hd)
>  {
> -	if (hd->host_pos_read < hd->host_app_pos)
> -		hd->host_avail = hd->host_app_pos - hd->host_pos_read;
> -	else if (hd->host_pos_read == hd->host_app_pos)
> +	if (hd->host_pos_local < hd->host_app_pos)
> +		hd->host_avail = hd->host_app_pos - hd->host_pos_local;
> +	else if (hd->host_pos_local == hd->host_app_pos)
>  		hd->host_avail = 0; /* empty */
>  	else
> -		hd->host_avail = hd->host_size -hd->host_pos_read +
> +		hd->host_avail = hd->host_size -hd->host_pos_local +
>  			hd->host_app_pos;
>  	hd->host_free = hd->host_size - hd->host_avail;
>  }
> @@ -163,11 +163,11 @@ static void host_dma_cb_playback(struct comp_dev *dev,
>  	comp_update_buffer_produce(hd->dma_buffer);
>  
>  	/* new local period, update host buffer position blks */
> -	hd->host_pos_read += local_elem->size;
> +	hd->host_pos_local += local_elem->size;
>  
>  	/* buffer overlap ? */
> -	if (hd->host_pos_read >= hd->host_size)
> -		hd->host_pos_read = 0;
> +	if (hd->host_pos_local >= hd->host_size)
> +		hd->host_pos_local = 0;
>  	host_update_buffer_consume(hd);
>  
>  	/* send IPC message to driver if needed */
> @@ -178,7 +178,7 @@ static void host_dma_cb_playback(struct comp_dev *dev,
>  		if (hd->host_avail) {
>  			/* update for host side */
>  			if (hd->host_pos) {
> -				*hd->host_pos = hd->host_pos_read;
> +				*hd->host_pos = hd->host_pos_local;
>  				ipc_stream_send_notification(dev, &hd->cp);
>  			}
>  		}
> @@ -281,13 +281,13 @@ static void host_dma_cb_capture(struct comp_dev *dev,
>  #endif
>  
>  	/* new local period, update host buffer position blks */
> -	hd->host_pos_read += local_elem->size;
> +	hd->host_pos_local += local_elem->size;
>  
>  	/* buffer overlap ? */
> -	if (hd->host_pos_read >= hd->host_size)
> -		hd->host_pos_read = 0;
> +	if (hd->host_pos_local >= hd->host_size)
> +		hd->host_pos_local = 0;
>  	if (hd->host_pos)
> -		*hd->host_pos = hd->host_pos_read;
> +		*hd->host_pos = hd->host_pos_local;
>  
>  	/* recalc available buffer space */
>  	comp_update_buffer_consume(hd->dma_buffer);
> @@ -381,7 +381,7 @@ static uint32_t host_finish_work(void *data, uint32_t udelay)
>  		trace_comp("hFw");
>  		/* update for host side */
>  		if (hd->host_pos) {
> -			*hd->host_pos = hd->host_pos_read;
> +			*hd->host_pos = hd->host_pos_local;
>  			/* send the last notification to host */
>  			ipc_stream_send_notification(dev, &hd->cp);
>  		}
> @@ -632,7 +632,7 @@ static int host_prepare(struct comp_dev *dev)
>  
>  	if (hd->host_pos)
>  		*hd->host_pos = 0;
> -	hd->host_pos_read = 0;
> +	hd->host_pos_local = 0;
>  	hd->host_period_pos = 0;
>  	hd->host_period_bytes =
>  		hd->params.period_frames * hd->params.frame_size;
> @@ -674,7 +674,7 @@ static int host_pointer_reset(struct comp_dev *dev)
>  	if (hd->host_pos)
>  		*hd->host_pos = 0;
>  	hd->host_app_pos = 0;
> -	hd->host_pos_read = 0;
> +	hd->host_pos_local = 0;
>  	hd->host_period_pos = 0;
>  
>  	host_update_buffer_consume(hd);