[alsa-devel] [RFC 10/11] ASoC: hda - add Skylake HD audio driver

[Takashi Iwai]

At Sun, 12 Apr 2015 18:06:17 +0530,
Subhransu S. Prusty wrote:
> 
> From: Jeeja KP <jeeja.kp at intel.com>
> 
> Add ASoC Skylake HD audio controller driver
> 
> Signed-off-by: Jeeja KP <jeeja.kp at intel.com>
> Signed-off-by: Subhransu S. Prusty <subhransu.s.prusty at intel.com>
> Signed-off-by: Vinod Koul <vinod.koul at intel.com>
> ---
>  include/sound/hdaudio.h |  11 +
>  sound/soc/hda/hda_skl.c | 829 ++++++++++++++++++++++++++++++++++++++++++++++++
>  sound/soc/hda/hda_skl.h |  49 +++
>  3 files changed, 889 insertions(+)
>  create mode 100644 sound/soc/hda/hda_skl.c
>  create mode 100644 sound/soc/hda/hda_skl.h
> 
> diff --git a/include/sound/hdaudio.h b/include/sound/hdaudio.h
> index 2d62410..1ef0b79 100644
> --- a/include/sound/hdaudio.h
> +++ b/include/sound/hdaudio.h
> @@ -197,6 +197,11 @@ struct hda_rb {
>  	u32 res[HDA_MAX_CODECS];	/* last read value */
>  };
>  
> +typedef unsigned int (*hdac_stream_get_pos_callback_t)(struct hdac_bus *,
> +			struct hdac_stream *);
> +typedef int (*hdac_stream_get_delay_callback_t)(struct hdac_bus *,
> +		struct hdac_stream *, unsigned int pos);
> +
>  struct hdac_bus {
>  	struct device *dev;
>  	const struct hdac_bus_ops *ops;
> @@ -233,6 +238,10 @@ struct hdac_bus {
>  	struct snd_dma_buffer rb;
>  	struct snd_dma_buffer posbuf;
>  
> +	/* position adjustment callbacks */
> +	hdac_stream_get_pos_callback_t get_position[2];
> +	hdac_stream_get_delay_callback_t get_delay[2];

So, do you still need the dynamic switch of get_position and get_delay
functions on SKL?  These are basically for old platforms that have no
position buffer support or unstable reads.

Otherwise you can use always LPIB and position buffers for position
and delay calculations.  That's why I didn't put them at the first
place.

> +
>  	/* hdac_stream linked list */
>  	struct list_head stream_list;
>  
> @@ -330,6 +339,8 @@ struct hdac_stream {
>  
>  	unsigned int opened:1;
>  	unsigned int running:1;
> +	unsigned int prepared:1;
> +	unsigned int irq_pending:1;

The irq_pending is also another question.  This was a workaround, and
whether it's still needed for the modern chips is not sure.


thanks,

Takashi