[alsa-devel] [PATCH 2/3] ASoC: Intel: Skylake: Add enum control for mic selection

[Takashi Iwai]

On Tue, 30 May 2017 10:40:27 +0200,
Subhransu S. Prusty wrote:
> 
> On Fri, May 26, 2017 at 01:05:41PM +0530, Vinod Koul wrote:
> > On Fri, May 26, 2017 at 08:57:44AM +0200, Takashi Iwai wrote:
> > > On Fri, 26 May 2017 05:20:02 +0200,
> > > Vinod Koul wrote:
> > > > 
> > > > From: "Kranthikumar, GudishaX" <gudishax.kranthikumar at intel.com>
> > > > 
> > > > User may prefer to select data from particular mics. A mic-select module
> > > > in DSP allows this selection.
> > > > 
> > > > Create possible enum controls to allow user to select a combination of
> > > > mics to capture data from. Based on the user selection, parameters are
> > > > generated and passed to mic-select module during init.
> > > > 
> > > > Signed-off-by: Kranthikumar, GudishaX <gudishax.kranthikumar at intel.com>
> > > > Signed-off-by: Dharageswari R <dharageswari.r 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>
> > > > ---
> > > >  sound/soc/intel/skylake/skl-topology.c       | 143 +++++++++++++++++++++++++++
> > > >  sound/soc/intel/skylake/skl-topology.h       |  20 ++++
> > > >  sound/soc/intel/skylake/skl-tplg-interface.h |   1 +
> > > >  3 files changed, 164 insertions(+)
> > > > 
> > > > diff --git a/sound/soc/intel/skylake/skl-topology.c b/sound/soc/intel/skylake/skl-topology.c
> > > > index b687ae455a61..141cfbe40c3a 100644
> > > > --- a/sound/soc/intel/skylake/skl-topology.c
> > > > +++ b/sound/soc/intel/skylake/skl-topology.c
> > > > @@ -36,6 +36,19 @@
> > > >  #define SKL_IN_DIR_BIT_MASK		BIT(0)
> > > >  #define SKL_PIN_COUNT_MASK		GENMASK(7, 4)
> > > >  
> > > > +static const int mic_mono_list[] = {
> > > > +0, 1, 2, 3,
> > > > +};
> > > > +static const int mic_stereo_list[][SKL_CH_STEREO] = {
> > > > +{0, 1}, {0, 2}, {0, 3}, {1, 2}, {1, 3}, {2, 3},
> > > > +};
> > > > +static const int mic_trio_list[][SKL_CH_TRIO] = {
> > > > +{0, 1, 2}, {0, 1, 3}, {0, 2, 3}, {1, 2, 3},
> > > > +};
> > > > +static const int mic_quatro_list[][SKL_CH_QUATRO] = {
> > > > +{0, 1, 2, 3},
> > > > +};
> > > > +
> > > >  void skl_tplg_d0i3_get(struct skl *skl, enum d0i3_capability caps)
> > > >  {
> > > >  	struct skl_d0i3_data *d0i3 =  &skl->skl_sst->d0i3;
> > > > @@ -1314,6 +1327,98 @@ static int skl_tplg_tlv_control_set(struct snd_kcontrol *kcontrol,
> > > >  	return 0;
> > > >  }
> > > >  
> > > > +static int skl_tplg_mic_control_get(struct snd_kcontrol *kcontrol,
> > > > +		struct snd_ctl_elem_value *ucontrol)
> > > > +{
> > > > +	struct snd_soc_dapm_widget *w = snd_soc_dapm_kcontrol_widget(kcontrol);
> > > > +	struct skl_module_cfg *mconfig = w->priv;
> > > > +	struct soc_enum *ec = (struct soc_enum *)kcontrol->private_value;
> > > > +	u32 ch_type = *((u32 *)ec->dobj.private);
> > > > +
> > > > +	if (mconfig->dmic_ch_type == ch_type)
> > > > +		ucontrol->value.integer.value[0] = mconfig->dmic_ch_combo_index;
> > > > +	else
> > > > +		ucontrol->value.integer.value[0] = 0;
> > > > +
> > > > +	return 0;
> > > > +}
> > > > +
> > > > +static int skl_fill_mic_sel_params(struct skl_module_cfg *mconfig,
> > > > +	struct skl_mic_sel_config *mic_cfg, struct device *dev)
> > > > +{
> > > > +	struct skl_specific_cfg *sp_cfg = &mconfig->formats_config;
> > > > +
> > > > +	sp_cfg->caps_size = sizeof(struct skl_mic_sel_config);
> > > > +	sp_cfg->set_params = SKL_PARAM_SET;
> > > > +	sp_cfg->param_id = 0x00;
> > > > +	if (!sp_cfg->caps) {
> > > > +		sp_cfg->caps = devm_kzalloc(dev, sp_cfg->caps_size, GFP_KERNEL);
> > > > +		if (!sp_cfg->caps)
> > > > +			return -ENOMEM;
> > > > +	}
> > > > +
> > > > +	mic_cfg->mic_switch = SKL_MIC_SEL_SWITCH;
> > > > +	mic_cfg->flags = 0;
> > > > +	memcpy(sp_cfg->caps, mic_cfg, sp_cfg->caps_size);
> > > > +
> > > > +	return 0;
> > > > +}
> > > > +
> > > > +static int skl_tplg_mic_control_set(struct snd_kcontrol *kcontrol,
> > > > +			struct snd_ctl_elem_value *ucontrol)
> > > > +{
> > > > +	struct snd_soc_dapm_widget *w = snd_soc_dapm_kcontrol_widget(kcontrol);
> > > > +	struct skl_module_cfg *mconfig = w->priv;
> > > > +	struct skl_mic_sel_config mic_cfg = {0};
> > > > +	struct soc_enum *ec = (struct soc_enum *)kcontrol->private_value;
> > > > +	u32 ch_type = *((u32 *)ec->dobj.private);
> > > > +	const int *list;
> > > > +	u8 in_ch, out_ch, index;
> > > > +
> > > > +	mconfig->dmic_ch_type = ch_type;
> > > > +	mconfig->dmic_ch_combo_index = ucontrol->value.integer.value[0];
> > > > +
> > > > +	/* enum control index 0 is INVALID, so no channels to be set */
> > > > +	if (mconfig->dmic_ch_combo_index == 0)
> > > > +		return 0;
> > > > +
> > > > +	/* No valid channel selection map for index 0, so offset by 1 */
> > > > +	index = mconfig->dmic_ch_combo_index - 1;
> > > > +
> > > > +	switch (ch_type) {
> > > > +	case SKL_CH_MONO:
> > > > +		list = &mic_mono_list[index];
> > > > +		break;
> > > > +
> > > > +	case SKL_CH_STEREO:
> > > > +		list = mic_stereo_list[index];
> > > > +		break;
> > > > +
> > > > +	case SKL_CH_TRIO:
> > > > +		list = mic_trio_list[index];
> > > > +		break;
> > > > +
> > > > +	case SKL_CH_QUATRO:
> > > > +		list = mic_quatro_list[index];
> > > > +		break;
> > > 
> > > How do you guarantee that index is in the array range?
> > > It looks easy to make things vulnerable with a firmware.
> > 
> > Yes a good catch, we should right check the index here and see if it is
> > within bounds, will fix it and update
> 
> Hi Takashi,
> 
> Shouldn't the alsa kernel or user space check for the index of enum control
> to be within the allowed range? If so, the driver doesn't need to check.

It's not the enum index at all.
Here the index is deduced in a very complex way:

	struct snd_soc_dapm_widget *w = snd_soc_dapm_kcontrol_widget(kcontrol);
	struct skl_module_cfg *mconfig = w->priv;
	.....
	index = mconfig->dmic_ch_combo_index - 1;

So I feel uneasy unless it's explicitly declared to be really safe.


Takashi