Re: [PATCH v2 1/2] ASoC: soc-compress: add a config item for soc-compress

["Jie, Yang" <yang.jie@intel.com>]

> -----Original Message-----
> From: Takashi Iwai [mailto:tiwai@suse.de]
> Sent: Monday, June 15, 2015 7:34 PM
> To: Jie, Yang
> Cc: broonie@kernel.org; alsa-devel@alsa-project.org; Girdwood, Liam R;
> vinod.koul@linux.intel.com; ramesh.babu@linux.intel.com; Zhang, Vivian
> Subject: Re: [PATCH v2 1/2] ASoC: soc-compress: add a config item for soc-
> compress
> 
> At Mon, 15 Jun 2015 11:20:44 +0800,
> Jie Yang wrote:
> >
> > We don't always need soc-compress in soc, here add a config item
> > SND_SOC_COMPRESS, please add 'select SND_SOC_COMPRESS' to driver
> > Kconfig when it is needed.
> >
> > Signed-off-by: Jie Yang <yang.jie@intel.com>
> > ---
> >  include/sound/soc.h     | 7 +++++++
> >  sound/soc/Kconfig       | 5 ++++-
> >  sound/soc/Makefile      | 3 ++-
> >  sound/soc/intel/Kconfig | 1 +
> >  4 files changed, 14 insertions(+), 2 deletions(-)
> >
> > diff --git a/include/sound/soc.h b/include/sound/soc.h index
> > 93df8bf..cc1cd4f 100644
> > --- a/include/sound/soc.h
> > +++ b/include/sound/soc.h
> > @@ -440,7 +440,14 @@ int snd_soc_platform_read(struct
> snd_soc_platform
> > *platform,  int snd_soc_platform_write(struct snd_soc_platform *platform,
> >  					unsigned int reg, unsigned int val);
> int soc_new_pcm(struct
> > snd_soc_pcm_runtime *rtd, int num);
> > +#if IS_ENABLED(CONFIG_SND_SOC_COMPRESS)
> >  int soc_new_compress(struct snd_soc_pcm_runtime *rtd, int num);
> > +#else
> > +static inline int soc_new_compress(struct snd_soc_pcm_runtime *rtd,
> > +int num) {
> > +       return -EPERM;
> > +}
> > +#endif
> 
> A dummy function in such a case has both merit and demerit.  The demerit is
> that you won't get errors if the driver really wants the compress support but
> just forgot to select the dependency.
 
Here I used -EPERM to return and tell caller that compress operation is not
permitted, does it make sense, Takashi?

Or can you suggest a better solution, according to this specific case?

Thanks,
~Keyon
> 
> 
> Takashi
> 
> >  struct snd_pcm_substream *snd_soc_get_dai_substream(struct
> snd_soc_card *card,
> >  		const char *dai_link, int stream);
> > diff --git a/sound/soc/Kconfig b/sound/soc/Kconfig index
> > e2828e1..a124759 100644
> > --- a/sound/soc/Kconfig
> > +++ b/sound/soc/Kconfig
> > @@ -9,7 +9,6 @@ menuconfig SND_SOC
> >  	select SND_JACK if INPUT=y || INPUT=SND
> >  	select REGMAP_I2C if I2C
> >  	select REGMAP_SPI if SPI_MASTER
> > -	select SND_COMPRESS_OFFLOAD
> >  	---help---
> >
> >  	  If you want ASoC support, you should say Y here and also to the @@
> > -30,6 +29,10 @@ config SND_SOC_GENERIC_DMAENGINE_PCM
> >  	bool
> >  	select SND_DMAENGINE_PCM
> >
> > +config SND_SOC_COMPRESS
> > +	tristate
> > +	select SND_COMPRESS_OFFLOAD
> > +
> >  # All the supported SoCs
> >  source "sound/soc/adi/Kconfig"
> >  source "sound/soc/atmel/Kconfig"
> > diff --git a/sound/soc/Makefile b/sound/soc/Makefile index
> > a0e1ee6..184c1e6 100644
> > --- a/sound/soc/Makefile
> > +++ b/sound/soc/Makefile
> > @@ -1,6 +1,7 @@
> >  snd-soc-core-objs := soc-core.o soc-dapm.o soc-jack.o soc-cache.o
> > soc-utils.o -snd-soc-core-objs += soc-pcm.o soc-compress.o soc-io.o
> > soc-devres.o soc-ops.o
> > +snd-soc-core-objs += soc-pcm.o soc-io.o soc-devres.o soc-ops.o
> >  snd-soc-core-objs += soc-topology.o
> > +snd-soc-core-$(CONFIG_SND_SOC_COMPRESS) += soc-compress.o
> >
> >  ifneq ($(CONFIG_SND_SOC_GENERIC_DMAENGINE_PCM),)
> >  snd-soc-core-objs += soc-generic-dmaengine-pcm.o diff --git
> > a/sound/soc/intel/Kconfig b/sound/soc/intel/Kconfig index
> > 791953f..e559174 100644
> > --- a/sound/soc/intel/Kconfig
> > +++ b/sound/soc/intel/Kconfig
> > @@ -12,6 +12,7 @@ config SND_MFLD_MACHINE
> >
> >  config SND_SST_MFLD_PLATFORM
> >  	tristate
> > +	select SND_SOC_COMPRESS
> >
> >  config SND_SST_IPC
> >  	tristate
> > --
> > 1.9.1
> >