[Intel-gfx] [PATCH] drm/i915/cnl: Enable Audio Pin Buffer.

[Vivi, Rodrigo]

On Thu, 2017-08-17 at 09:26 +0530, Sanyog Kale wrote:
> On Wed, Aug 16, 2017 at 06:46:26PM -0500, Pandiyan, Dhinakaran wrote:
> > On Thu, 2017-07-06 at 14:03 -0700, Rodrigo Vivi wrote:
> > > Starting on CNL, we need to enable Audio Pin Buffer.
> > > 
> > > By the spec it seems that this is part of audio programming,
> > 
> > I am not very clear where the pin buffer enabling/disabling step falls
> > in the audio programming sequence. From what I understand, audio codec
> > enable/disable is controlled by i915, if pin buffer enable/disable is
> > part of that, then we don't need a call back. It's difficult to know
> > where this function is going to be used without seeing the audio driver
> > patch that makes of use of this.

Sanyog, I couldn't find all the old emails with spec pointing out the
time that we needed to set this bit. Do you still have?
Anything you could share when publishing the patches?

> >
> 
> From audio point of view, we are working on correct sequence where this ops
> will be called. However during CNL Power-ON we enabled the pin buf using ops
> as part of azx_reset.

Ok, so let's put this on hold while audio drivers are not ready.
It will be on internal branch anyways.
When audio driver gets ready we re-submit all together.

>  
> > > so let's give them the hability to set/unset this as needed.
> > 
> > typo s/hability/ability
> > > 
> > > v2: With a hook so audio driver can control it.
> > > v3: Put back reg definition lost on v2.
> > > 
> > > Cc: Dhinakaran Pandiyan <dhinakaran.pandiyan at intel.com>
> > > Cc: Jani Nikula <jani.nikula at intel.com>
> > > Cc: Sanyog Kale <sanyog.r.kale at intel.com>
> > > Signed-off-by: Rodrigo Vivi <rodrigo.vivi at intel.com>
> > > ---
> > >  drivers/gpu/drm/i915/i915_reg.h    |  3 +++
> > >  drivers/gpu/drm/i915/intel_audio.c | 16 ++++++++++++++++
> > >  include/drm/i915_component.h       |  6 ++++++
> > >  3 files changed, 25 insertions(+)
> > > 
> > > diff --git a/drivers/gpu/drm/i915/i915_reg.h b/drivers/gpu/drm/i915/i915_reg.h
> > > index 64cc674..aab38da 100644
> > > --- a/drivers/gpu/drm/i915/i915_reg.h
> > > +++ b/drivers/gpu/drm/i915/i915_reg.h
> > > @@ -2643,6 +2643,9 @@ enum skl_disp_power_wells {
> > >  #define I915_HDMI_LPE_AUDIO_BASE	(VLV_DISPLAY_BASE + 0x65000)
> > >  #define I915_HDMI_LPE_AUDIO_SIZE	0x1000
> > >  
> > > +#define AUDIO_PIN_BUF_CTL		_MMIO(0x48414)
> > > +#define AUDIO_PIN_BUF_ENABLE		(1 << 31)
> > > +
> > >  /* DisplayPort Audio w/ LPE */
> > >  #define VLV_AUD_CHICKEN_BIT_REG		_MMIO(VLV_DISPLAY_BASE + 0x62F38)
> > >  #define VLV_CHICKEN_BIT_DBG_ENABLE	(1 << 0)
> > > diff --git a/drivers/gpu/drm/i915/intel_audio.c b/drivers/gpu/drm/i915/intel_audio.c
> > > index d805b6e..0c83254 100644
> > > --- a/drivers/gpu/drm/i915/intel_audio.c
> > > +++ b/drivers/gpu/drm/i915/intel_audio.c
> > > @@ -865,6 +865,21 @@ static int i915_audio_component_get_eld(struct device *kdev, int port,
> > >  	return ret;
> > >  }
> > >  
> > > +static void i915_audio_component_pin_buf(struct device *kdev, bool enable)
> > > +{
> > 
> > Does it matter whether the audio codec is enabled or disabled when this
> > call comes in? i.e., do we need some sort of check here? Or do we assume
> > the audio driver knows exactly when to enable or disable pin buffer?
> > 
> > 
> > 
> > > +	struct drm_i915_private *dev_priv = kdev_to_i915(kdev);
> > > +
> > > +	if (!IS_CANNONLAKE(dev_priv))
> > 
> > Should this be a INTEL_GEN() < 10 since the register is gen10+? I am not
> > particular about either of the options.
> > 
> > > +		return;
> > > +
> > > +	if (enable)
> > > +		I915_WRITE(AUDIO_PIN_BUF_CTL, I915_READ(AUDIO_PIN_BUF_CTL) |
> > > +			   AUDIO_PIN_BUF_ENABLE);
> > > +	else
> > > +		I915_WRITE(AUDIO_PIN_BUF_CTL, I915_READ(AUDIO_PIN_BUF_CTL) &
> > > +			   ~AUDIO_PIN_BUF_ENABLE);
> > > +}
> > > +
> > >  static const struct i915_audio_component_ops i915_audio_component_ops = {
> > >  	.owner		= THIS_MODULE,
> > >  	.get_power	= i915_audio_component_get_power,
> > > @@ -873,6 +888,7 @@ static int i915_audio_component_get_eld(struct device *kdev, int port,
> > >  	.get_cdclk_freq	= i915_audio_component_get_cdclk_freq,
> > >  	.sync_audio_rate = i915_audio_component_sync_audio_rate,
> > >  	.get_eld	= i915_audio_component_get_eld,
> > > +	.pin_buf	= i915_audio_component_pin_buf,
> > >  };
> > >  
> > >  static int i915_audio_component_bind(struct device *i915_kdev,
> > > diff --git a/include/drm/i915_component.h b/include/drm/i915_component.h
> > > index 545c6e0..b8875d4 100644
> > > --- a/include/drm/i915_component.h
> > > +++ b/include/drm/i915_component.h
> > > @@ -79,6 +79,12 @@ struct i915_audio_component_ops {
> > >  	 */
> > >  	int (*get_eld)(struct device *, int port, int pipe, bool *enabled,
> > >  		       unsigned char *buf, int max_bytes);
> > > +	/**
> > > +	 * @pin_buf: Enable or disable pin buffer.
> > > +	 *
> > > +	 * Allow audio driver the toggle pin buffer.
> > > +	 */
> > > +	void (*pin_buf)(struct device *, bool enable);
> > >  };
> > >  
> > >  /**
>