Re: [PATCH 15/30] drm/dp: Add backpointer to drm_device in drm_dp_aux
On Sun, 2021-02-21 at 20:21 +0200, Laurent Pinchart wrote:
> Hi Lyude,
>
> Thank you for the patch.
>
> On Fri, Feb 19, 2021 at 04:53:11PM -0500, Lyude Paul wrote:
> > This is something that we've wanted for a while now: the ability to
> > actually look up the respective drm_device for a given drm_dp_aux struct.
> > This will also allow us to transition over to using the drm_dbg_*() helpers
> > for debug message printing, as we'll finally have a drm_device to reference
> > for doing so.
>
> Isn't it better to use the existing dev field ? If you have multiple DP
> outputs for one DRM device, using the DRM device name in debug messages
> won't tell which output the message corresponds to.
Well the thing is dev won't tell you that either - on most SoCs the DP AUX
adapter is it's own platform device that isn't a child of the DRM device. Also,
that's what the ability to name AUX channels is supposed to be there for.
> > Note that there is one limitation with this - because some DP AUX adapters
> > exist as platform devices which are initialized independently of their
> > respective DRM devices, one cannot rely on drm_dp_aux->drm_dev to always be
> > non-NULL until drm_dp_aux_register() has been called. We make sure to point
> > this out in the documentation for struct drm_dp_aux.
> >
> > Signed-off-by: Lyude Paul
> > ---
> > drivers/gpu/drm/amd/amdgpu/atombios_dp.c | 1 +
> > .../gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_mst_types.c | 1 +
> > drivers/gpu/drm/bridge/analogix/analogix-anx6345.c | 1 +
> > drivers/gpu/drm/bridge/analogix/analogix-anx78xx.c | 1 +
> > drivers/gpu/drm/bridge/analogix/analogix_dp_core.c | 1 +
> > drivers/gpu/drm/bridge/cadence/cdns-mhdp8546-core.c | 1 +
> > drivers/gpu/drm/bridge/tc358767.c | 1 +
> > drivers/gpu/drm/bridge/ti-sn65dsi86.c | 1 +
> > drivers/gpu/drm/drm_dp_aux_dev.c | 6 ++
> > drivers/gpu/drm/drm_dp_mst_topology.c | 1 +
> > drivers/gpu/drm/i915/display/intel_dp_aux.c | 1 +
> > drivers/gpu/drm/msm/edp/edp.h | 3 +--
> > drivers/gpu/drm/msm/edp/edp_aux.c | 5 +++--
> > drivers/gpu/drm/msm/edp/edp_ctrl.c | 2 +-
> > drivers/gpu/drm/nouveau/nouveau_connector.c | 1 +
> > drivers/gpu/drm/radeon/atombios_dp.c | 1 +
> > drivers/gpu/drm/tegra/dpaux.c | 1 +
> > drivers/gpu/drm/xlnx/zynqmp_dp.c | 1 +
> > include/drm/drm_dp_helper.h | 9 -
> > 19 files changed, 33 insertions(+), 6 deletions(-)
> >
> > diff --git a/drivers/gpu/drm/amd/amdgpu/atombios_dp.c
> > b/drivers/gpu/drm/amd/amdgpu/atombios_dp.c
> > index a3ba9ca11e98..6d35da65e09f 100644
> > --- a/drivers/gpu/drm/amd/amdgpu/atombios_dp.c
> > +++ b/drivers/gpu/drm/amd/amdgpu/atombios_dp.c
> > @@ -188,6 +188,7 @@ void amdgpu_atombios_dp_aux_init(struct amdgpu_connector
> > *amdgpu_connector)
> > {
> > amdgpu_connector->ddc_bus->rec.hpd = amdgpu_connector->hpd.hpd;
> > amdgpu_connector->ddc_bus->aux.transfer =
> > amdgpu_atombios_dp_aux_transfer;
> > + amdgpu_connector->ddc_bus->aux.drm_dev = amdgpu_connector->base.dev;
> > drm_dp_aux_init(_connector->ddc_bus->aux);
> > amdgpu_connector->ddc_bus->has_aux = true;
> > }
> > diff --git a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_mst_types.c
> > b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_mst_types.c
> > index 41b09ab22233..163641b44339 100644
> > --- a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_mst_types.c
> > +++ b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_mst_types.c
> > @@ -431,6 +431,7 @@ void amdgpu_dm_initialize_dp_connector(struct
> > amdgpu_display_manager *dm,
> > link_index);
> > aconnector->dm_dp_aux.aux.transfer = dm_dp_aux_transfer;
> > aconnector->dm_dp_aux.ddc_service = aconnector->dc_link->ddc;
> > + aconnector->dm_dp_aux.aux.drm_dev = dm->ddev;
> >
> > drm_dp_aux_init(>dm_dp_aux.aux);
> > drm_dp_cec_register_connector(>dm_dp_aux.aux,
> > diff --git a/drivers/gpu/drm/bridge/analogix/analogix-anx6345.c
> > b/drivers/gpu/drm/bridge/analogix/analogix-anx6345.c
> > index aa6cda458eb9..e33cd077595a 100644
> > --- a/drivers/gpu/drm/bridge/analogix/analogix-anx6345.c
> > +++ b/drivers/gpu/drm/bridge/analogix/analogix-anx6345.c
> > @@ -537,6 +537,7 @@ static int anx6345_bridge_attach(struct drm_bridge
> > *bridge,
> > /* Register aux channel */
> > anx6345->aux.name = "DP-AUX";
> > anx6345->aux.dev = >client->dev;
> > + anx6345->aux.drm_dev = bridge->dev;
> > anx6345->aux.transfer = anx6345_aux_transfer;
> >
> > err = drm_dp_aux_register(>aux);
> > diff --git a/drivers/gpu/drm/bridge/analogix/analogix-anx78xx.c
> >
Re: [PATCH 15/30] drm/dp: Add backpointer to drm_device in drm_dp_aux
Hi Lyude,
Thank you for the patch.
On Fri, Feb 19, 2021 at 04:53:11PM -0500, Lyude Paul wrote:
> This is something that we've wanted for a while now: the ability to
> actually look up the respective drm_device for a given drm_dp_aux struct.
> This will also allow us to transition over to using the drm_dbg_*() helpers
> for debug message printing, as we'll finally have a drm_device to reference
> for doing so.
Isn't it better to use the existing dev field ? If you have multiple DP
outputs for one DRM device, using the DRM device name in debug messages
won't tell which output the message corresponds to.
> Note that there is one limitation with this - because some DP AUX adapters
> exist as platform devices which are initialized independently of their
> respective DRM devices, one cannot rely on drm_dp_aux->drm_dev to always be
> non-NULL until drm_dp_aux_register() has been called. We make sure to point
> this out in the documentation for struct drm_dp_aux.
>
> Signed-off-by: Lyude Paul
> ---
> drivers/gpu/drm/amd/amdgpu/atombios_dp.c | 1 +
> .../gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_mst_types.c | 1 +
> drivers/gpu/drm/bridge/analogix/analogix-anx6345.c | 1 +
> drivers/gpu/drm/bridge/analogix/analogix-anx78xx.c | 1 +
> drivers/gpu/drm/bridge/analogix/analogix_dp_core.c | 1 +
> drivers/gpu/drm/bridge/cadence/cdns-mhdp8546-core.c | 1 +
> drivers/gpu/drm/bridge/tc358767.c| 1 +
> drivers/gpu/drm/bridge/ti-sn65dsi86.c| 1 +
> drivers/gpu/drm/drm_dp_aux_dev.c | 6 ++
> drivers/gpu/drm/drm_dp_mst_topology.c| 1 +
> drivers/gpu/drm/i915/display/intel_dp_aux.c | 1 +
> drivers/gpu/drm/msm/edp/edp.h| 3 +--
> drivers/gpu/drm/msm/edp/edp_aux.c| 5 +++--
> drivers/gpu/drm/msm/edp/edp_ctrl.c | 2 +-
> drivers/gpu/drm/nouveau/nouveau_connector.c | 1 +
> drivers/gpu/drm/radeon/atombios_dp.c | 1 +
> drivers/gpu/drm/tegra/dpaux.c| 1 +
> drivers/gpu/drm/xlnx/zynqmp_dp.c | 1 +
> include/drm/drm_dp_helper.h | 9 -
> 19 files changed, 33 insertions(+), 6 deletions(-)
>
> diff --git a/drivers/gpu/drm/amd/amdgpu/atombios_dp.c
> b/drivers/gpu/drm/amd/amdgpu/atombios_dp.c
> index a3ba9ca11e98..6d35da65e09f 100644
> --- a/drivers/gpu/drm/amd/amdgpu/atombios_dp.c
> +++ b/drivers/gpu/drm/amd/amdgpu/atombios_dp.c
> @@ -188,6 +188,7 @@ void amdgpu_atombios_dp_aux_init(struct amdgpu_connector
> *amdgpu_connector)
> {
> amdgpu_connector->ddc_bus->rec.hpd = amdgpu_connector->hpd.hpd;
> amdgpu_connector->ddc_bus->aux.transfer =
> amdgpu_atombios_dp_aux_transfer;
> + amdgpu_connector->ddc_bus->aux.drm_dev = amdgpu_connector->base.dev;
> drm_dp_aux_init(_connector->ddc_bus->aux);
> amdgpu_connector->ddc_bus->has_aux = true;
> }
> diff --git a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_mst_types.c
> b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_mst_types.c
> index 41b09ab22233..163641b44339 100644
> --- a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_mst_types.c
> +++ b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_mst_types.c
> @@ -431,6 +431,7 @@ void amdgpu_dm_initialize_dp_connector(struct
> amdgpu_display_manager *dm,
> link_index);
> aconnector->dm_dp_aux.aux.transfer = dm_dp_aux_transfer;
> aconnector->dm_dp_aux.ddc_service = aconnector->dc_link->ddc;
> + aconnector->dm_dp_aux.aux.drm_dev = dm->ddev;
>
> drm_dp_aux_init(>dm_dp_aux.aux);
> drm_dp_cec_register_connector(>dm_dp_aux.aux,
> diff --git a/drivers/gpu/drm/bridge/analogix/analogix-anx6345.c
> b/drivers/gpu/drm/bridge/analogix/analogix-anx6345.c
> index aa6cda458eb9..e33cd077595a 100644
> --- a/drivers/gpu/drm/bridge/analogix/analogix-anx6345.c
> +++ b/drivers/gpu/drm/bridge/analogix/analogix-anx6345.c
> @@ -537,6 +537,7 @@ static int anx6345_bridge_attach(struct drm_bridge
> *bridge,
> /* Register aux channel */
> anx6345->aux.name = "DP-AUX";
> anx6345->aux.dev = >client->dev;
> + anx6345->aux.drm_dev = bridge->dev;
> anx6345->aux.transfer = anx6345_aux_transfer;
>
> err = drm_dp_aux_register(>aux);
> diff --git a/drivers/gpu/drm/bridge/analogix/analogix-anx78xx.c
> b/drivers/gpu/drm/bridge/analogix/analogix-anx78xx.c
> index f20558618220..5e6a0ed39199 100644
> --- a/drivers/gpu/drm/bridge/analogix/analogix-anx78xx.c
> +++ b/drivers/gpu/drm/bridge/analogix/analogix-anx78xx.c
> @@ -905,6 +905,7 @@ static int anx78xx_bridge_attach(struct drm_bridge
> *bridge,
> /* Register aux channel */
> anx78xx->aux.name = "DP-AUX";
> anx78xx->aux.dev = >client->dev;
> + anx78xx->aux.drm_dev = bridge->dev;
> anx78xx->aux.transfer = anx78xx_aux_transfer;
>
> err =
[PATCH 15/30] drm/dp: Add backpointer to drm_device in drm_dp_aux
This is something that we've wanted for a while now: the ability to
actually look up the respective drm_device for a given drm_dp_aux struct.
This will also allow us to transition over to using the drm_dbg_*() helpers
for debug message printing, as we'll finally have a drm_device to reference
for doing so.
Note that there is one limitation with this - because some DP AUX adapters
exist as platform devices which are initialized independently of their
respective DRM devices, one cannot rely on drm_dp_aux->drm_dev to always be
non-NULL until drm_dp_aux_register() has been called. We make sure to point
this out in the documentation for struct drm_dp_aux.
Signed-off-by: Lyude Paul
---
drivers/gpu/drm/amd/amdgpu/atombios_dp.c | 1 +
.../gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_mst_types.c | 1 +
drivers/gpu/drm/bridge/analogix/analogix-anx6345.c | 1 +
drivers/gpu/drm/bridge/analogix/analogix-anx78xx.c | 1 +
drivers/gpu/drm/bridge/analogix/analogix_dp_core.c | 1 +
drivers/gpu/drm/bridge/cadence/cdns-mhdp8546-core.c | 1 +
drivers/gpu/drm/bridge/tc358767.c| 1 +
drivers/gpu/drm/bridge/ti-sn65dsi86.c| 1 +
drivers/gpu/drm/drm_dp_aux_dev.c | 6 ++
drivers/gpu/drm/drm_dp_mst_topology.c| 1 +
drivers/gpu/drm/i915/display/intel_dp_aux.c | 1 +
drivers/gpu/drm/msm/edp/edp.h| 3 +--
drivers/gpu/drm/msm/edp/edp_aux.c| 5 +++--
drivers/gpu/drm/msm/edp/edp_ctrl.c | 2 +-
drivers/gpu/drm/nouveau/nouveau_connector.c | 1 +
drivers/gpu/drm/radeon/atombios_dp.c | 1 +
drivers/gpu/drm/tegra/dpaux.c| 1 +
drivers/gpu/drm/xlnx/zynqmp_dp.c | 1 +
include/drm/drm_dp_helper.h | 9 -
19 files changed, 33 insertions(+), 6 deletions(-)
diff --git a/drivers/gpu/drm/amd/amdgpu/atombios_dp.c
b/drivers/gpu/drm/amd/amdgpu/atombios_dp.c
index a3ba9ca11e98..6d35da65e09f 100644
--- a/drivers/gpu/drm/amd/amdgpu/atombios_dp.c
+++ b/drivers/gpu/drm/amd/amdgpu/atombios_dp.c
@@ -188,6 +188,7 @@ void amdgpu_atombios_dp_aux_init(struct amdgpu_connector
*amdgpu_connector)
{
amdgpu_connector->ddc_bus->rec.hpd = amdgpu_connector->hpd.hpd;
amdgpu_connector->ddc_bus->aux.transfer =
amdgpu_atombios_dp_aux_transfer;
+ amdgpu_connector->ddc_bus->aux.drm_dev = amdgpu_connector->base.dev;
drm_dp_aux_init(_connector->ddc_bus->aux);
amdgpu_connector->ddc_bus->has_aux = true;
}
diff --git a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_mst_types.c
b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_mst_types.c
index 41b09ab22233..163641b44339 100644
--- a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_mst_types.c
+++ b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_mst_types.c
@@ -431,6 +431,7 @@ void amdgpu_dm_initialize_dp_connector(struct
amdgpu_display_manager *dm,
link_index);
aconnector->dm_dp_aux.aux.transfer = dm_dp_aux_transfer;
aconnector->dm_dp_aux.ddc_service = aconnector->dc_link->ddc;
+ aconnector->dm_dp_aux.aux.drm_dev = dm->ddev;
drm_dp_aux_init(>dm_dp_aux.aux);
drm_dp_cec_register_connector(>dm_dp_aux.aux,
diff --git a/drivers/gpu/drm/bridge/analogix/analogix-anx6345.c
b/drivers/gpu/drm/bridge/analogix/analogix-anx6345.c
index aa6cda458eb9..e33cd077595a 100644
--- a/drivers/gpu/drm/bridge/analogix/analogix-anx6345.c
+++ b/drivers/gpu/drm/bridge/analogix/analogix-anx6345.c
@@ -537,6 +537,7 @@ static int anx6345_bridge_attach(struct drm_bridge *bridge,
/* Register aux channel */
anx6345->aux.name = "DP-AUX";
anx6345->aux.dev = >client->dev;
+ anx6345->aux.drm_dev = bridge->dev;
anx6345->aux.transfer = anx6345_aux_transfer;
err = drm_dp_aux_register(>aux);
diff --git a/drivers/gpu/drm/bridge/analogix/analogix-anx78xx.c
b/drivers/gpu/drm/bridge/analogix/analogix-anx78xx.c
index f20558618220..5e6a0ed39199 100644
--- a/drivers/gpu/drm/bridge/analogix/analogix-anx78xx.c
+++ b/drivers/gpu/drm/bridge/analogix/analogix-anx78xx.c
@@ -905,6 +905,7 @@ static int anx78xx_bridge_attach(struct drm_bridge *bridge,
/* Register aux channel */
anx78xx->aux.name = "DP-AUX";
anx78xx->aux.dev = >client->dev;
+ anx78xx->aux.drm_dev = bridge->dev;
anx78xx->aux.transfer = anx78xx_aux_transfer;
err = drm_dp_aux_register(>aux);
diff --git a/drivers/gpu/drm/bridge/analogix/analogix_dp_core.c
b/drivers/gpu/drm/bridge/analogix/analogix_dp_core.c
index f115233b1cb9..550814ca2139 100644
--- a/drivers/gpu/drm/bridge/analogix/analogix_dp_core.c
+++ b/drivers/gpu/drm/bridge/analogix/analogix_dp_core.c
@@ -1765,6 +1765,7 @@ int analogix_dp_bind(struct analogix_dp_device *dp,
struct drm_device *drm_dev)
dp->aux.name =
