Re: [PATCH] drm/radeon: Add HD-audio component notifier support (v4)

[Alex Deucher]

Applied.  Thanks!

Alex

On Mon, Oct 24, 2022 at 11:41 AM Takashi Iwai <tiwai@xxxxxxx> wrote:
>
> This patch adds the support for the notification of HD-audio hotplug
> via the already existing drm_audio_component framework to radeon
> driver.  This allows us more reliable hotplug notification and ELD
> transfer without accessing HD-audio bus; it's more efficient, and more
> importantly, it works without waking up the runtime PM.
>
> The implementation is rather simplistic: radeon driver provides the
> get_eld ops for HD-audio, and it notifies the audio hotplug via
> pin_eld_notify callback upon each radeon_audio_enable() call.
> The pin->id is referred as the port number passed to the notifier
> callback, and the corresponding connector is looked through the
> encoder list in the get_eld callback in turn.
>
> The bind and unbind callbacks handle the device-link so that it
> assures the PM call order.
>
> Also, as a gratis bonus, this patch "fixes" the regression by the
> recent change in HD-audio to be more strict for the HDMI/DP
> connection, too.  Since the HD-audio HDMI/DP codec requires both the
> connection bit and the valid ELD to be provided, it started failing on
> some RADEON gfx boards where the ELD update performed instably.  As
> this change switches the communication to a direct way between the
> audio and the graphics drivers, now the system receives the proper
> ELD, and the HDMI/DP hotplug starts working again.
>
> [ v2: fix the logic in radeon_audio_component_get_eld to walk the
>   connector list since that is where the EDID lives and we can
>   derive the encoder from the connector because the encoder has
>   not been assigned at this point (i.e., during monitor probe).
>
>   v3: the component binding is moved outside radeon_audio_init() and
>   _fini(), as those are called from suspend/resume, too.
>   Drop modeset lock calls that caused Oops.
>   Moved Kconfig change so that it can be applied on older kernels.
>
>   v4: revive drm_modeset_lock*() again, add the missing
>   device_link_remove() call at unbinding ]
>
> Link: https://gitlab.freedesktop.org/drm/amd/-/issues/1569
> Signed-off-by: Takashi Iwai <tiwai@xxxxxxx>
> ---
>  drivers/gpu/drm/Kconfig                |   1 +
>  drivers/gpu/drm/radeon/radeon.h        |   7 ++
>  drivers/gpu/drm/radeon/radeon_audio.c  | 113 +++++++++++++++++++++++++
>  drivers/gpu/drm/radeon/radeon_device.c |   3 +
>  4 files changed, 124 insertions(+)
>
> diff --git a/drivers/gpu/drm/Kconfig b/drivers/gpu/drm/Kconfig
> index 34f5a092c99e..fa986075e8fb 100644
> --- a/drivers/gpu/drm/Kconfig
> +++ b/drivers/gpu/drm/Kconfig
> @@ -243,6 +243,7 @@ config DRM_RADEON
>          select DRM_KMS_HELPER
>          select DRM_TTM
>         select DRM_TTM_HELPER
> +       select SND_HDA_COMPONENT if SND_HDA_CORE
>         select POWER_SUPPLY
>         select HWMON
>         select BACKLIGHT_CLASS_DEVICE
> diff --git a/drivers/gpu/drm/radeon/radeon.h b/drivers/gpu/drm/radeon/radeon.h
> index 166c18d62f6d..d82424525f5a 100644
> --- a/drivers/gpu/drm/radeon/radeon.h
> +++ b/drivers/gpu/drm/radeon/radeon.h
> @@ -79,6 +79,7 @@
>  #include <drm/ttm/ttm_execbuf_util.h>
>
>  #include <drm/drm_gem.h>
> +#include <drm/drm_audio_component.h>
>
>  #include "radeon_family.h"
>  #include "radeon_mode.h"
> @@ -1796,6 +1797,8 @@ struct r600_audio {
>         struct radeon_audio_funcs *hdmi_funcs;
>         struct radeon_audio_funcs *dp_funcs;
>         struct radeon_audio_basic_funcs *funcs;
> +       struct drm_audio_component *component;
> +       bool component_registered;
>  };
>
>  /*
> @@ -2994,6 +2997,10 @@ void radeon_irq_kms_set_irq_n_enabled(struct radeon_device *rdev,
>                                       bool enable, const char *name,
>                                       unsigned n);
>
> +/* Audio component binding */
> +void radeon_audio_component_init(struct radeon_device *rdev);
> +void radeon_audio_component_fini(struct radeon_device *rdev);
> +
>  #include "radeon_object.h"
>
>  #endif
> diff --git a/drivers/gpu/drm/radeon/radeon_audio.c b/drivers/gpu/drm/radeon/radeon_audio.c
> index 7c5e80d03fc9..4ceb90556127 100644
> --- a/drivers/gpu/drm/radeon/radeon_audio.c
> +++ b/drivers/gpu/drm/radeon/radeon_audio.c
> @@ -23,6 +23,7 @@
>   */
>
>  #include <linux/gcd.h>
> +#include <linux/component.h>
>
>  #include <drm/drm_crtc.h>
>  #include "dce6_afmt.h"
> @@ -180,6 +181,9 @@ static struct radeon_audio_funcs dce6_dp_funcs = {
>         .dpms = evergreen_dp_enable,
>  };
>
> +static void radeon_audio_component_notify(struct drm_audio_component *acomp,
> +                                         int port);
> +
>  static void radeon_audio_enable(struct radeon_device *rdev,
>                                 struct r600_audio_pin *pin, u8 enable_mask)
>  {
> @@ -207,6 +211,8 @@ static void radeon_audio_enable(struct radeon_device *rdev,
>
>         if (rdev->audio.funcs->enable)
>                 rdev->audio.funcs->enable(rdev, pin, enable_mask);
> +
> +       radeon_audio_component_notify(rdev->audio.component, pin->id);
>  }
>
>  static void radeon_audio_interface_init(struct radeon_device *rdev)
> @@ -721,3 +727,110 @@ unsigned int radeon_audio_decode_dfs_div(unsigned int div)
>         else
>                 return 0;
>  }
> +
> +/*
> + * Audio component support
> + */
> +static void radeon_audio_component_notify(struct drm_audio_component *acomp,
> +                                         int port)
> +{
> +       if (acomp && acomp->audio_ops && acomp->audio_ops->pin_eld_notify)
> +               acomp->audio_ops->pin_eld_notify(acomp->audio_ops->audio_ptr,
> +                                                port, -1);
> +}
> +
> +static int radeon_audio_component_get_eld(struct device *kdev, int port,
> +                                         int pipe, bool *enabled,
> +                                         unsigned char *buf, int max_bytes)
> +{
> +       struct drm_device *dev = dev_get_drvdata(kdev);
> +       struct drm_encoder *encoder;
> +       struct radeon_encoder *radeon_encoder;
> +       struct radeon_encoder_atom_dig *dig;
> +       struct drm_connector *connector;
> +       int ret = 0;
> +
> +       *enabled = false;
> +       list_for_each_entry(connector, &dev->mode_config.connector_list, head) {
> +               const struct drm_connector_helper_funcs *connector_funcs =
> +                       connector->helper_private;
> +               encoder = connector_funcs->best_encoder(connector);
> +
> +               if (!encoder)
> +                       continue;
> +               if (!radeon_encoder_is_digital(encoder))
> +                       continue;
> +               radeon_encoder = to_radeon_encoder(encoder);
> +               dig = radeon_encoder->enc_priv;
> +               if (!dig->pin || dig->pin->id != port)
> +                       continue;
> +               *enabled = true;
> +               ret = drm_eld_size(connector->eld);
> +               memcpy(buf, connector->eld, min(max_bytes, ret));
> +               break;
> +       }
> +
> +       return ret;
> +}
> +
> +static const struct drm_audio_component_ops radeon_audio_component_ops = {
> +       .get_eld = radeon_audio_component_get_eld,
> +};
> +
> +static int radeon_audio_component_bind(struct device *kdev,
> +                                      struct device *hda_kdev, void *data)
> +{
> +       struct drm_device *dev = dev_get_drvdata(kdev);
> +       struct radeon_device *rdev = dev->dev_private;
> +       struct drm_audio_component *acomp = data;
> +
> +       if (WARN_ON(!device_link_add(hda_kdev, kdev, DL_FLAG_STATELESS)))
> +               return -ENOMEM;
> +
> +       drm_modeset_lock_all(dev);
> +       acomp->ops = &radeon_audio_component_ops;
> +       acomp->dev = kdev;
> +       rdev->audio.component = acomp;
> +       drm_modeset_unlock_all(dev);
> +
> +       return 0;
> +}
> +
> +static void radeon_audio_component_unbind(struct device *kdev,
> +                                         struct device *hda_kdev, void *data)
> +{
> +       struct drm_device *dev = dev_get_drvdata(kdev);
> +       struct radeon_device *rdev = dev->dev_private;
> +       struct drm_audio_component *acomp = data;
> +
> +       device_link_remove(hda_kdev, kdev);
> +
> +       drm_modeset_lock_all(dev);
> +       rdev->audio.component = NULL;
> +       acomp->ops = NULL;
> +       acomp->dev = NULL;
> +       drm_modeset_unlock_all(dev);
> +}
> +
> +static const struct component_ops radeon_audio_component_bind_ops = {
> +       .bind   = radeon_audio_component_bind,
> +       .unbind = radeon_audio_component_unbind,
> +};
> +
> +void radeon_audio_component_init(struct radeon_device *rdev)
> +{
> +       if (rdev->audio.component_registered ||
> +           !radeon_audio || !radeon_audio_chipset_supported(rdev))
> +               return;
> +
> +       if (!component_add(rdev->dev, &radeon_audio_component_bind_ops))
> +               rdev->audio.component_registered = true;
> +}
> +
> +void radeon_audio_component_fini(struct radeon_device *rdev)
> +{
> +       if (rdev->audio.component_registered) {
> +               component_del(rdev->dev, &radeon_audio_component_bind_ops);
> +               rdev->audio.component_registered = false;
> +       }
> +}
> diff --git a/drivers/gpu/drm/radeon/radeon_device.c b/drivers/gpu/drm/radeon/radeon_device.c
> index a556b6be1137..17bfbbe906c8 100644
> --- a/drivers/gpu/drm/radeon/radeon_device.c
> +++ b/drivers/gpu/drm/radeon/radeon_device.c
> @@ -1451,6 +1451,8 @@ int radeon_device_init(struct radeon_device *rdev,
>                         goto failed;
>         }
>
> +       radeon_audio_component_init(rdev);
> +
>         r = radeon_ib_ring_tests(rdev);
>         if (r)
>                 DRM_ERROR("ib ring test failed (%d).\n", r);
> @@ -1513,6 +1515,7 @@ void radeon_device_fini(struct radeon_device *rdev)
>         rdev->shutdown = true;
>         /* evict vram memory */
>         radeon_bo_evict_vram(rdev);
> +       radeon_audio_component_fini(rdev);
>         radeon_fini(rdev);
>         if (!pci_is_thunderbolt_attached(rdev->pdev))
>                 vga_switcheroo_unregister_client(rdev->pdev);
> --
> 2.35.3
>