[alsa-devel] [PATCH v2 2/2] ASoC: omap-mcpdm: Replace legacy driver

[Liam Girdwood]

On 19/08/11 09:49, Lars-Peter Clausen wrote:
> On 08/19/2011 10:38 AM, Lars-Peter Clausen wrote:
>> On 08/19/2011 09:41 AM, Peter Ujfalusi wrote:
>>> From: Misael Lopez Cruz <misael.lopez at ti.com>
>>>
>>> Reasons for the replacement:
>>> The current driver for McPDM was developed to support the legacy mode only.
>>> In preparation for the ABE support the current driver stack need the be
>>> replaced.
>>> The new driver is much simpler, easier to extend, and it also fixes some of the
>>> issues with the old stack.
>>>
>>> Main changes:
>>> - single file for omap-mcpdm (mcpdm.c/h removed)
>>> - Define names for registers, bits cleaned up, prefixed
>>> - Full-duplex audio operation (arecord | aplay) has been fixed
>>> - Less code
>>>
>>> McPDM need to be turned off _after_ the codec's DAC/ADC has been powered down.
>>> The solution for this without extensive change in core:
>>> Use DAPM_SUPPLY to turn off the McPDM interface.
>>> The machine driver connects the "OMAP McPDM Interface" to the codec's DAC/ADC,
>>> so after audio activity we can be sure that the host side McPDM is turned off
>>> at the correct time.
>>>
>>> Signed-off-by: Misael Lopez Cruz <misael.lopez at ti.com>
>>> Signed-off-by: Liam Girdwood <lrg at ti.com>
>>> Signed-off-by: Sebastien Guiriec <s-guiriec at ti.com>
>>> Signed-off-by: Peter Ujfalusi <peter.ujfalusi at ti.com>
>>> ---
>>>  sound/soc/omap/Makefile     |    2 +-
>>>  sound/soc/omap/mcpdm.c      |  472 -------------------------
>>>  sound/soc/omap/mcpdm.h      |  152 --------
>>>  sound/soc/omap/omap-mcpdm.c |  823 ++++++++++++++++++++++++++++---------------
>>>  sound/soc/omap/omap-mcpdm.h |   97 +++++
>>>  sound/soc/omap/sdp4430.c    |   14 +-
>>>  6 files changed, 655 insertions(+), 905 deletions(-)
>>>  delete mode 100644 sound/soc/omap/mcpdm.c
>>>  delete mode 100644 sound/soc/omap/mcpdm.h
>>>  rewrite sound/soc/omap/omap-mcpdm.c (46%)
>>>  create mode 100644 sound/soc/omap/omap-mcpdm.h
>>>
>>> diff --git a/sound/soc/omap/Makefile b/sound/soc/omap/Makefile
>>> index 59e2c8d..052fd75 100644
>>> --- a/sound/soc/omap/Makefile
>>> +++ b/sound/soc/omap/Makefile
>>> @@ -1,7 +1,7 @@
>>>  # OMAP Platform Support
>>>  snd-soc-omap-objs := omap-pcm.o
>>>  snd-soc-omap-mcbsp-objs := omap-mcbsp.o
>>> -snd-soc-omap-mcpdm-objs := omap-mcpdm.o mcpdm.o
>>> +snd-soc-omap-mcpdm-objs := omap-mcpdm.o
>>>  snd-soc-omap-hdmi-objs := omap-hdmi.o
>>>  
>>>  obj-$(CONFIG_SND_OMAP_SOC) += snd-soc-omap.o
>>> diff --git a/sound/soc/omap/mcpdm.c b/sound/soc/omap/mcpdm.c
>>> deleted file mode 100644
>>> index 9746a49..0000000
>>> --- a/sound/soc/omap/mcpdm.c
>>> +++ /dev/null
>>> @@ -1,472 +0,0 @@
>>> [...]
>>> +static int omap_mcpdm_interface_event(struct snd_soc_dapm_widget *w,
>>> +		struct snd_kcontrol *kcontrol, int event)
>>> +{
>>> +	struct omap_mcpdm *mcpdm = w->private_data;
>>
>> Can't you use
>> struct omap_mcpdm *mcpdm = snd_soc_codec_get_drvdata(codec)?
> 
> sorry:
> struct omap_mcpdm *mcpdm =  snd_soc_platform_get_drvdata(w->platform);
> 
> 
>>
>> This would avoid having to add the private_data field to the widget struct. In
>> it's current form it will only really work, if there is just one instance of
>> the driver using the widget. And if that's the case you can use a global
>> variable directly anyway.

This wont work as the McPDM DAI is neither a codec or a platform driver. It's best to give the widgets some private data since we may have other uses for it too.

Thanks

Liam