Re: [PATCH v2 1/3] drm/i915/hda: Add audio component stub

Takashi Iwai
2016-05-13T10:04:59Z

On Fri, 13 May 2016 11:50:09 +0200,
Imre Deak wrote:
>
> On Fri, 2016-05-13 at 09:48 +0200, Takashi Iwai wrote:
> > On Thu, 12 May 2016 20:06:53 +0200,
> > Imre Deak wrote:
> > >
> > > User may pass nomodeset or i915.modeset=0 option to disable i915 KMS
> > > explicitly.  Although this itself works fine, it breaks the weak
> > > dependency the HD-audio driver requires, and it's the reason the
> > > delayed component binding isn't implemented in HD-audio.  Since i915
> > > doesn't notify its disablement, HD-audio would be blocked
> > > unnecessarily endlessly, waiting for the bind with i915.
> > >
> > > This patch introduces a stub audio component binding when i915 driver
> > > is loaded with KMS off like the boot options above.  Then i915 driver
> > > still registers the slave component but with the new "disabled" ops
> > > flag, so that the master component (HD-audio) can know clearly the
> > > slave state.
> > >
> > > v2:
> > > - Fail the probe in case component registration fails, instead of
> > >   suppressing the error. (Ville)
> > > - Register the component only for the real PCI device function.
> > >
> > > CC: Ville Syrjälä <ville.syrjala@linux.intel.com>
> > > Signed-off-by: Imre Deak <imre.deak@intel.com>
> > > Signed-off-by: Takashi Iwai <tiwai@suse.de>
> >
> > I haven't received v2 for the rest two patches.  I suppose they are
> > unchanged from v1?
>
> I haven't changed them. They look ok to me, but someone else should
> review patch 3.
>
> > It'd be good if we can get this into 4.7.  Will this go through drm
> > tree, or my tree?  I don't mind either way.  If you merge this do
> > drm(-intel) tree, just let me know the stable git id so that I can
> > merge it to sound.git tree with my rest two patches.
>
> Adding Daniel. I think for bisectability patch 1 and 2 should be
> combined, then that combined patch could go through drm-intel, while
> patch 3 could go through the sound tree.

Well, the patch 2 and patch 3 have to be applied after the patch 1 in
anyway. So, I can apply 2 and 3 once after merging the change for
patch 1 back into sound tree. That is, three options:

1. Apply all 1, 2 and 3 in drm tree:
however, patch 3 won't be applied cleanly to 4.6, so drm tree would
need to merge sound for-next branch beforehand.

2. Apply all 1, 2 and 3 in sound tree:
patch 1 won't be applied to 4.6 cleanly, so sound tree needs to
merge drm tree at first.

3. Apply patch 1 to drm tree, then apply 2 and 3 in sound tree:
sound tree will merge drm tree applied with patch 1, then apply 2
and 3 on top of it.

Takashi

>
> --Imre
>
> > thanks,
> >
> > Takashi
> >
> > > ---
> > >  drivers/gpu/drm/i915/i915_drv.c    | 51 +++++++++++++++++++++++-------------
> > >  drivers/gpu/drm/i915/intel_audio.c | 53 ++++++++++++++++++++++++++++++++++++++
> > >  drivers/gpu/drm/i915/intel_drv.h   |  2 ++
> > >  include/drm/i915_component.h       |  5 ++++
> > >  4 files changed, 93 insertions(+), 18 deletions(-)
> > >
> > > diff --git a/drivers/gpu/drm/i915/i915_drv.c b/drivers/gpu/drm/i915/i915_drv.c
> > > index 5ae7960..b127810 100644
> > > --- a/drivers/gpu/drm/i915/i915_drv.c
> > > +++ b/drivers/gpu/drm/i915/i915_drv.c
> > > @@ -1016,12 +1016,6 @@ static int i915_pci_probe(struct pci_dev *pdev, const struct pci_device_id *ent)
> > >   struct intel_device_info *intel_info =
> > >   (struct intel_device_info *) ent->driver_data;
> > >
> > > - if (IS_PRELIMINARY_HW(intel_info) && !i915.preliminary_hw_support) {
> > > - DRM_INFO("This hardware requires preliminary hardware support.\n"
> > > -  "See CONFIG_DRM_I915_PRELIMINARY_HW_SUPPORT, and/or modparam preliminary_hw_support\n");
> > > - return -ENODEV;
> > > - }
> > > -
> > >   /* Only bind to function 0 of the device. Early generations
> > >    * used function 1 as a placeholder for multi-head. This causes
> > >    * us confusion instead, especially on the systems where both
> > > @@ -1030,6 +1024,29 @@ static int i915_pci_probe(struct pci_dev *pdev, const struct pci_device_id *ent)
> > >   if (PCI_FUNC(pdev->devfn))
> > >   return -ENODEV;
> > >
> > > + if (!(driver.driver_features & DRIVER_MODESET)) {
> > > + int ret;
> > > +
> > > + /*
> > > +  * Notify the HDA driver so that it doesn't block waiting for
> > > +  * i915 to become ready.
> > > +  */
> > > + ret = i915_audio_component_stub_init(&pdev->dev);
> > > + if (ret)
> > > + return ret;
> > > +
> > > + /* Silently fail loading to not upset userspace. */
> > > + DRM_DEBUG_DRIVER("KMS and UMS disabled.\n");
> > > +
> > > + return 0;
> > > + }
> > > +
> > > + if (IS_PRELIMINARY_HW(intel_info) && !i915.preliminary_hw_support) {
> > > + DRM_INFO("This hardware requires preliminary hardware support.\n"
> > > +  "See CONFIG_DRM_I915_PRELIMINARY_HW_SUPPORT, and/or modparam preliminary_hw_support\n");
> > > + return -ENODEV;
> > > + }
> > > +
> > >   /*
> > >    * apple-gmux is needed on dual GPU MacBook Pro
> > >    * to probe the panel if we're the inactive GPU.
> > > @@ -1045,8 +1062,15 @@ static int i915_pci_probe(struct pci_dev *pdev, const struct pci_device_id *ent)
> > >  static void
> > >  i915_pci_remove(struct pci_dev *pdev)
> > >  {
> > > - struct drm_device *dev = pci_get_drvdata(pdev);
> > > + struct drm_device *dev;
> > >
> > > + if (!(driver.driver_features & DRIVER_MODESET)) {
> > > + i915_audio_component_stub_cleanup(&pdev->dev);
> > > +
> > > + return;
> > > + }
> > > +
> > > + dev = pci_get_drvdata(pdev);
> > >   drm_put_dev(dev);
> > >  }
> > >
> > > @@ -1767,24 +1791,15 @@ static int __init i915_init(void)
> > >   if (vgacon_text_force() && i915.modeset == -1)
> > >   driver.driver_features &= ~DRIVER_MODESET;
> > >
> > > - if (!(driver.driver_features & DRIVER_MODESET)) {
> > > - /* Silently fail loading to not upset userspace. */
> > > - DRM_DEBUG_DRIVER("KMS and UMS disabled.\n");
> > > - return 0;
> > > - }
> > > -
> > >   if (i915.nuclear_pageflip)
> > >   driver.driver_features |= DRIVER_ATOMIC;
> > >
> > > - return drm_pci_init(&driver, &i915_pci_driver);
> > > + return pci_register_driver(&i915_pci_driver);
> > >  }
> > >
> > >  static void __exit i915_exit(void)
> > >  {
> > > - if (!(driver.driver_features & DRIVER_MODESET))
> > > - return; /* Never loaded a driver. */
> > > -
> > > - drm_pci_exit(&driver, &i915_pci_driver);
> > > + pci_unregister_driver(&i915_pci_driver);
> > >  }
> > >
> > >  module_init(i915_init);
> > > diff --git a/drivers/gpu/drm/i915/intel_audio.c b/drivers/gpu/drm/i915/intel_audio.c
> > > index b9329c2..603b3fe 100644
> > > --- a/drivers/gpu/drm/i915/intel_audio.c
> > > +++ b/drivers/gpu/drm/i915/intel_audio.c
> > > @@ -824,3 +824,56 @@ void i915_audio_component_cleanup(struct drm_i915_private *dev_priv)
> > >   component_del(dev_priv->dev->dev, &i915_audio_component_bind_ops);
> > >   dev_priv->audio_component_registered = false;
> > >  }
> > > +
> > > +static const struct i915_audio_component_ops i915_audio_component_stub_ops = {
> > > + .owner = THIS_MODULE,
> > > + .disabled = true,
> > > +};
> > > +
> > > +static int i915_audio_component_stub_bind(struct device *i915_stub_dev,
> > > +   struct device *hda_dev, void *data)
> > > +{
> > > + struct i915_audio_component *acomp = data;
> > > +
> > > + if (WARN_ON(acomp->ops || acomp->dev))
> > > + return -EEXIST;
> > > +
> > > + acomp->ops = &i915_audio_component_stub_ops;
> > > + acomp->dev = i915_stub_dev;
> > > +
> > > + return 0;
> > > +}
> > > +
> > > +static void i915_audio_component_stub_unbind(struct device *i915_stub_dev,
> > > +      struct device *hda_dev, void *data)
> > > +{
> > > + struct i915_audio_component *acomp = data;
> > > +
> > > + acomp->ops = NULL;
> > > + acomp->dev = NULL;
> > > +}
> > > +
> > > +static const struct component_ops i915_audio_component_stub_bind_ops = {
> > > + .bind = i915_audio_component_stub_bind,
> > > + .unbind = i915_audio_component_stub_unbind,
> > > +};
> > > +
> > > +static const struct file_operations component_stub_dev_ops = {
> > > + .owner = THIS_MODULE,
> > > +};
> > > +
> > > +int i915_audio_component_stub_init(struct device *dev)
> > > +{
> > > + int ret;
> > > +
> > > + ret = component_add(dev, &i915_audio_component_stub_bind_ops);
> > > + if (ret < 0)
> > > + DRM_ERROR("failed to add audio stub component (%d)\n", ret);
> > > +
> > > + return ret;
> > > +}
> > > +
> > > +void i915_audio_component_stub_cleanup(struct device *dev)
> > > +{
> > > + component_del(dev, &i915_audio_component_stub_bind_ops);
> > > +}
> > > diff --git a/drivers/gpu/drm/i915/intel_drv.h b/drivers/gpu/drm/i915/intel_drv.h
> > > index 0a9c10d..a828e00 100644
> > > --- a/drivers/gpu/drm/i915/intel_drv.h
> > > +++ b/drivers/gpu/drm/i915/intel_drv.h
> > > @@ -1111,6 +1111,8 @@ void intel_audio_codec_enable(struct intel_encoder *encoder);
> > >  void intel_audio_codec_disable(struct intel_encoder *encoder);
> > >  void i915_audio_component_init(struct drm_i915_private *dev_priv);
> > >  void i915_audio_component_cleanup(struct drm_i915_private *dev_priv);
> > > +int i915_audio_component_stub_init(struct device *dev);
> > > +void i915_audio_component_stub_cleanup(struct device *dev);
> > >
> > >  /* intel_display.c */
> > >  void intel_update_rawclk(struct drm_i915_private *dev_priv);
> > > diff --git a/include/drm/i915_component.h b/include/drm/i915_component.h
> > > index b46fa0e..33da85a 100644
> > > --- a/include/drm/i915_component.h
> > > +++ b/include/drm/i915_component.h
> > > @@ -39,6 +39,11 @@ struct i915_audio_component_ops {
> > >    */
> > >   struct module *owner;
> > >   /**
> > > +  * @disabled: i915 driver loaded with modeset=0, the services provided
> > > +  * via the audio component interface are not available.
> > > +  */
> > > + bool disabled;
> > > + /**
> > >    * @get_power: get the POWER_DOMAIN_AUDIO power well
> > >    *
> > >    * Request the power well to be turned on.