Re: [Nouveau] [PATCH 4/5] drm_dp_cec: add plumbing in preparation for MST support

2020-09-09 Thread Sam McNally
On Wed, 2 Sep 2020 at 04:12, Lyude Paul  wrote:
>
> Super minor nitpicks:
>
> On Tue, 2020-09-01 at 16:22 +1000, Sam McNally wrote:
> > From: Hans Verkuil 
> >
> > Signed-off-by: Hans Verkuil 
> > [sa...@chromium.org:
> >  - rebased
> >  - removed polling-related changes
> >  - moved the calls to drm_dp_cec_(un)set_edid() into the next patch
> > ]
> > Signed-off-by: Sam McNally 
> > ---
> >
> >  .../display/amdgpu_dm/amdgpu_dm_mst_types.c   |  2 +-
> >  drivers/gpu/drm/drm_dp_cec.c  | 22 ++-
> >  drivers/gpu/drm/i915/display/intel_dp.c   |  2 +-
> >  drivers/gpu/drm/nouveau/nouveau_connector.c   |  2 +-
> >  include/drm/drm_dp_helper.h   |  6 +++--
> >  5 files changed, 19 insertions(+), 15 deletions(-)
> >
> > 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 461fa4da0a34..6e7075893ec9 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
> > @@ -419,7 +419,7 @@ void amdgpu_dm_initialize_dp_connector(struct
> > amdgpu_display_manager *dm,
> >
> >   drm_dp_aux_init(>dm_dp_aux.aux);
> >   drm_dp_cec_register_connector(>dm_dp_aux.aux,
> > -   >base);
> > +   >base, false);
> >
> >   if (aconnector->base.connector_type == DRM_MODE_CONNECTOR_eDP)
> >   return;
> > diff --git a/drivers/gpu/drm/drm_dp_cec.c b/drivers/gpu/drm/drm_dp_cec.c
> > index 3ab2609f9ec7..04ab7b88055c 100644
> > --- a/drivers/gpu/drm/drm_dp_cec.c
> > +++ b/drivers/gpu/drm/drm_dp_cec.c
> > @@ -14,6 +14,7 @@
> >  #include 
> >  #include 
> >  #include 
> > +#include 
> >
> >  /*
> >   * Unfortunately it turns out that we have a chicken-and-egg situation
> > @@ -338,8 +339,6 @@ void drm_dp_cec_set_edid(struct drm_dp_aux *aux, const
> > struct edid *edid)
> >   if (aux->cec.adap) {
> >   if (aux->cec.adap->capabilities == cec_caps &&
> >   aux->cec.adap->available_log_addrs == num_las) {
> > - /* Unchanged, so just set the phys addr */
> > - cec_s_phys_addr_from_edid(aux->cec.adap, edid);
> >   goto unlock;
> >   }
>
> May as well drop the braces here
>
> >   /*
> > @@ -364,15 +363,16 @@ void drm_dp_cec_set_edid(struct drm_dp_aux *aux, const
> > struct edid *edid)
> >   if (cec_register_adapter(aux->cec.adap, connector->dev->dev)) {
> >   cec_delete_adapter(aux->cec.adap);
> >   aux->cec.adap = NULL;
> > - } else {
> > - /*
> > -  * Update the phys addr for the new CEC adapter. When called
> > -  * from drm_dp_cec_register_connector() edid == NULL, so in
> > -  * that case the phys addr is just invalidated.
> > -  */
> > - cec_s_phys_addr_from_edid(aux->cec.adap, edid);
> >   }
> >  unlock:
> > + /*
> > +  * Update the phys addr for the new CEC adapter. When called
> > +  * from drm_dp_cec_register_connector() edid == NULL, so in
> > +  * that case the phys addr is just invalidated.
> > +  */
> > + if (aux->cec.adap && edid) {
> > + cec_s_phys_addr_from_edid(aux->cec.adap, edid);
> > + }
>
> And here
>
> >   mutex_unlock(>cec.lock);
> >  }
> >  EXPORT_SYMBOL(drm_dp_cec_set_edid);
> > @@ -418,6 +418,7 @@ EXPORT_SYMBOL(drm_dp_cec_unset_edid);
> >   * drm_dp_cec_register_connector() - register a new connector
> >   * @aux: DisplayPort AUX channel
> >   * @connector: drm connector
> > + * @is_mst: set to true if this is an MST branch
> >   *
> >   * A new connector was registered with associated CEC adapter name and
> >   * CEC adapter parent device. After registering the name and parent
> > @@ -425,12 +426,13 @@ EXPORT_SYMBOL(drm_dp_cec_unset_edid);
> >   * CEC and to register a CEC adapter if that is the case.
> >   */
> >  void drm_dp_cec_register_connector(struct drm_dp_aux *aux,
> > -struct drm_connector *connector)
> > +struct drm_connector *connector, bool 
> > is_mst)
> >  {
> >   WARN_ON(aux->cec.adap);
> >   if (WARN_ON(!aux->transfer))
> >   return;
> >   aux->cec.connector = connector;
> > + aux->cec.is_mst = is_mst;
>
> Also JFYI, you can also check aux->is_remote, but maybe you've got another
> reason for copying this here
>

I think this was just an artefact of this patch originally being
written before aux->is_remote was added. Switching to it mostly
removes the need for this patch, and leaving drm_dp_cec_set_edid()
unchanged, as Hans suggests, removes the rest.

> Either way:
>
> Reviewed-by: Lyude Paul 
>
> ...Also, maybe this is just a coincidence - but do I know your name from
> somewhere? Perhaps an IRC community from long ago?
>

Not that I can 

Re: [Nouveau] [PATCH 4/5] drm_dp_cec: add plumbing in preparation for MST support

2020-09-09 Thread Sam McNally
On Tue, 8 Sep 2020 at 18:41, Hans Verkuil  wrote:
>
> On 01/09/2020 08:22, Sam McNally wrote:
> > From: Hans Verkuil 
> >
> > Signed-off-by: Hans Verkuil 
> > [sa...@chromium.org:
> >  - rebased
> >  - removed polling-related changes
> >  - moved the calls to drm_dp_cec_(un)set_edid() into the next patch
> > ]
> > Signed-off-by: Sam McNally 
> > ---
> >
> >  .../display/amdgpu_dm/amdgpu_dm_mst_types.c   |  2 +-
> >  drivers/gpu/drm/drm_dp_cec.c  | 22 ++-
> >  drivers/gpu/drm/i915/display/intel_dp.c   |  2 +-
> >  drivers/gpu/drm/nouveau/nouveau_connector.c   |  2 +-
> >  include/drm/drm_dp_helper.h   |  6 +++--
> >  5 files changed, 19 insertions(+), 15 deletions(-)
> >
> > 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 461fa4da0a34..6e7075893ec9 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
> > @@ -419,7 +419,7 @@ void amdgpu_dm_initialize_dp_connector(struct 
> > amdgpu_display_manager *dm,
> >
> >   drm_dp_aux_init(>dm_dp_aux.aux);
> >   drm_dp_cec_register_connector(>dm_dp_aux.aux,
> > -   >base);
> > +   >base, false);
> >
> >   if (aconnector->base.connector_type == DRM_MODE_CONNECTOR_eDP)
> >   return;
> > diff --git a/drivers/gpu/drm/drm_dp_cec.c b/drivers/gpu/drm/drm_dp_cec.c
> > index 3ab2609f9ec7..04ab7b88055c 100644
> > --- a/drivers/gpu/drm/drm_dp_cec.c
> > +++ b/drivers/gpu/drm/drm_dp_cec.c
> > @@ -14,6 +14,7 @@
> >  #include 
> >  #include 
> >  #include 
> > +#include 
> >
> >  /*
> >   * Unfortunately it turns out that we have a chicken-and-egg situation
> > @@ -338,8 +339,6 @@ void drm_dp_cec_set_edid(struct drm_dp_aux *aux, const 
> > struct edid *edid)
> >   if (aux->cec.adap) {
> >   if (aux->cec.adap->capabilities == cec_caps &&
> >   aux->cec.adap->available_log_addrs == num_las) {
> > - /* Unchanged, so just set the phys addr */
> > - cec_s_phys_addr_from_edid(aux->cec.adap, edid);
> >   goto unlock;
> >   }
> >   /*
> > @@ -364,15 +363,16 @@ void drm_dp_cec_set_edid(struct drm_dp_aux *aux, 
> > const struct edid *edid)
> >   if (cec_register_adapter(aux->cec.adap, connector->dev->dev)) {
> >   cec_delete_adapter(aux->cec.adap);
> >   aux->cec.adap = NULL;
> > - } else {
> > - /*
> > -  * Update the phys addr for the new CEC adapter. When called
> > -  * from drm_dp_cec_register_connector() edid == NULL, so in
> > -  * that case the phys addr is just invalidated.
> > -  */
> > - cec_s_phys_addr_from_edid(aux->cec.adap, edid);
> >   }
> >  unlock:
> > + /*
> > +  * Update the phys addr for the new CEC adapter. When called
> > +  * from drm_dp_cec_register_connector() edid == NULL, so in
> > +  * that case the phys addr is just invalidated.
> > +  */
>
> The comment is no longer in sync with the code: if EDID == NULL, then
> nothing is done due to the edid check in the 'if' below.
>
> > + if (aux->cec.adap && edid) {
>
> I think this should just be: if (aux->cec.adap)
>
> Also, the {} aren't necessary here.
>
> > + cec_s_phys_addr_from_edid(aux->cec.adap, edid);
> > + }
> >   mutex_unlock(>cec.lock);
> >  }
> >  EXPORT_SYMBOL(drm_dp_cec_set_edid);
>
> Frankly, the changes to this function should be dropped completely, from
> what I can see they are not necessary. It was done in my original patch
> because of the way I handled mst, but you did it differently (and I think
> better), so these changes are no longer needed.
>
> I know I am actually commenting on my old patch, but that patch was from a
> work-in-progress git branch and was never meant as a 'proper' patch.
>
> However, what complicates matters is that after digging a bit more I 
> discovered
> that commit 732300154980 ("drm: Do not call drm_dp_cec_set_edid() while 
> registering
> DP connectors") changed drm_dp_cec_register_connector() so that it no longer
> calls drm_dp_cec_set_edid(), but the comments there and in this function were
> not updated. It would be nice if you can add a patch fixing these outdated
> comments.
>
> Regardless of that change in commit 732300154980, the edid pointer can still 
> be
> NULL and the existing behavior should be kept (i.e. create a CEC device, but 
> with
> an invalid physical address since there is no EDID for some reason).
>
> Regards,
>
> Hans
>

Thanks. Leaving drm_dp_cec_set_edid() unchanged combined with Lyude's
suggestion to use aux->is_remote removes the need for this patch
entirely.

> > @@ -418,6 +418,7 @@ EXPORT_SYMBOL(drm_dp_cec_unset_edid);
> >   * 

Re: [Nouveau] [PATCH 4/5] drm_dp_cec: add plumbing in preparation for MST support

2020-09-08 Thread Hans Verkuil
On 01/09/2020 08:22, Sam McNally wrote:
> From: Hans Verkuil 
> 
> Signed-off-by: Hans Verkuil 
> [sa...@chromium.org:
>  - rebased
>  - removed polling-related changes
>  - moved the calls to drm_dp_cec_(un)set_edid() into the next patch
> ]
> Signed-off-by: Sam McNally 
> ---
> 
>  .../display/amdgpu_dm/amdgpu_dm_mst_types.c   |  2 +-
>  drivers/gpu/drm/drm_dp_cec.c  | 22 ++-
>  drivers/gpu/drm/i915/display/intel_dp.c   |  2 +-
>  drivers/gpu/drm/nouveau/nouveau_connector.c   |  2 +-
>  include/drm/drm_dp_helper.h   |  6 +++--
>  5 files changed, 19 insertions(+), 15 deletions(-)
> 
> 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 461fa4da0a34..6e7075893ec9 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
> @@ -419,7 +419,7 @@ void amdgpu_dm_initialize_dp_connector(struct 
> amdgpu_display_manager *dm,
>  
>   drm_dp_aux_init(>dm_dp_aux.aux);
>   drm_dp_cec_register_connector(>dm_dp_aux.aux,
> -   >base);
> +   >base, false);
>  
>   if (aconnector->base.connector_type == DRM_MODE_CONNECTOR_eDP)
>   return;
> diff --git a/drivers/gpu/drm/drm_dp_cec.c b/drivers/gpu/drm/drm_dp_cec.c
> index 3ab2609f9ec7..04ab7b88055c 100644
> --- a/drivers/gpu/drm/drm_dp_cec.c
> +++ b/drivers/gpu/drm/drm_dp_cec.c
> @@ -14,6 +14,7 @@
>  #include 
>  #include 
>  #include 
> +#include 
>  
>  /*
>   * Unfortunately it turns out that we have a chicken-and-egg situation
> @@ -338,8 +339,6 @@ void drm_dp_cec_set_edid(struct drm_dp_aux *aux, const 
> struct edid *edid)
>   if (aux->cec.adap) {
>   if (aux->cec.adap->capabilities == cec_caps &&
>   aux->cec.adap->available_log_addrs == num_las) {
> - /* Unchanged, so just set the phys addr */
> - cec_s_phys_addr_from_edid(aux->cec.adap, edid);
>   goto unlock;
>   }
>   /*
> @@ -364,15 +363,16 @@ void drm_dp_cec_set_edid(struct drm_dp_aux *aux, const 
> struct edid *edid)
>   if (cec_register_adapter(aux->cec.adap, connector->dev->dev)) {
>   cec_delete_adapter(aux->cec.adap);
>   aux->cec.adap = NULL;
> - } else {
> - /*
> -  * Update the phys addr for the new CEC adapter. When called
> -  * from drm_dp_cec_register_connector() edid == NULL, so in
> -  * that case the phys addr is just invalidated.
> -  */
> - cec_s_phys_addr_from_edid(aux->cec.adap, edid);
>   }
>  unlock:
> + /*
> +  * Update the phys addr for the new CEC adapter. When called
> +  * from drm_dp_cec_register_connector() edid == NULL, so in
> +  * that case the phys addr is just invalidated.
> +  */

The comment is no longer in sync with the code: if EDID == NULL, then
nothing is done due to the edid check in the 'if' below.

> + if (aux->cec.adap && edid) {

I think this should just be: if (aux->cec.adap)

Also, the {} aren't necessary here.

> + cec_s_phys_addr_from_edid(aux->cec.adap, edid);
> + }
>   mutex_unlock(>cec.lock);
>  }
>  EXPORT_SYMBOL(drm_dp_cec_set_edid);

Frankly, the changes to this function should be dropped completely, from
what I can see they are not necessary. It was done in my original patch
because of the way I handled mst, but you did it differently (and I think
better), so these changes are no longer needed.

I know I am actually commenting on my old patch, but that patch was from a
work-in-progress git branch and was never meant as a 'proper' patch.

However, what complicates matters is that after digging a bit more I discovered
that commit 732300154980 ("drm: Do not call drm_dp_cec_set_edid() while 
registering
DP connectors") changed drm_dp_cec_register_connector() so that it no longer
calls drm_dp_cec_set_edid(), but the comments there and in this function were
not updated. It would be nice if you can add a patch fixing these outdated
comments.

Regardless of that change in commit 732300154980, the edid pointer can still be
NULL and the existing behavior should be kept (i.e. create a CEC device, but 
with
an invalid physical address since there is no EDID for some reason).

Regards,

Hans

> @@ -418,6 +418,7 @@ EXPORT_SYMBOL(drm_dp_cec_unset_edid);
>   * drm_dp_cec_register_connector() - register a new connector
>   * @aux: DisplayPort AUX channel
>   * @connector: drm connector
> + * @is_mst: set to true if this is an MST branch
>   *
>   * A new connector was registered with associated CEC adapter name and
>   * CEC adapter parent device. After registering the name and parent
> @@ -425,12 +426,13 @@ EXPORT_SYMBOL(drm_dp_cec_unset_edid);
>   * CEC and to register a CEC adapter if 

Re: [Nouveau] [PATCH 4/5] drm_dp_cec: add plumbing in preparation for MST support

2020-09-01 Thread Lyude Paul
Super minor nitpicks:

On Tue, 2020-09-01 at 16:22 +1000, Sam McNally wrote:
> From: Hans Verkuil 
> 
> Signed-off-by: Hans Verkuil 
> [sa...@chromium.org:
>  - rebased
>  - removed polling-related changes
>  - moved the calls to drm_dp_cec_(un)set_edid() into the next patch
> ]
> Signed-off-by: Sam McNally 
> ---
> 
>  .../display/amdgpu_dm/amdgpu_dm_mst_types.c   |  2 +-
>  drivers/gpu/drm/drm_dp_cec.c  | 22 ++-
>  drivers/gpu/drm/i915/display/intel_dp.c   |  2 +-
>  drivers/gpu/drm/nouveau/nouveau_connector.c   |  2 +-
>  include/drm/drm_dp_helper.h   |  6 +++--
>  5 files changed, 19 insertions(+), 15 deletions(-)
> 
> 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 461fa4da0a34..6e7075893ec9 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
> @@ -419,7 +419,7 @@ void amdgpu_dm_initialize_dp_connector(struct
> amdgpu_display_manager *dm,
>  
>   drm_dp_aux_init(>dm_dp_aux.aux);
>   drm_dp_cec_register_connector(>dm_dp_aux.aux,
> -   >base);
> +   >base, false);
>  
>   if (aconnector->base.connector_type == DRM_MODE_CONNECTOR_eDP)
>   return;
> diff --git a/drivers/gpu/drm/drm_dp_cec.c b/drivers/gpu/drm/drm_dp_cec.c
> index 3ab2609f9ec7..04ab7b88055c 100644
> --- a/drivers/gpu/drm/drm_dp_cec.c
> +++ b/drivers/gpu/drm/drm_dp_cec.c
> @@ -14,6 +14,7 @@
>  #include 
>  #include 
>  #include 
> +#include 
>  
>  /*
>   * Unfortunately it turns out that we have a chicken-and-egg situation
> @@ -338,8 +339,6 @@ void drm_dp_cec_set_edid(struct drm_dp_aux *aux, const
> struct edid *edid)
>   if (aux->cec.adap) {
>   if (aux->cec.adap->capabilities == cec_caps &&
>   aux->cec.adap->available_log_addrs == num_las) {
> - /* Unchanged, so just set the phys addr */
> - cec_s_phys_addr_from_edid(aux->cec.adap, edid);
>   goto unlock;
>   }

May as well drop the braces here

>   /*
> @@ -364,15 +363,16 @@ void drm_dp_cec_set_edid(struct drm_dp_aux *aux, const
> struct edid *edid)
>   if (cec_register_adapter(aux->cec.adap, connector->dev->dev)) {
>   cec_delete_adapter(aux->cec.adap);
>   aux->cec.adap = NULL;
> - } else {
> - /*
> -  * Update the phys addr for the new CEC adapter. When called
> -  * from drm_dp_cec_register_connector() edid == NULL, so in
> -  * that case the phys addr is just invalidated.
> -  */
> - cec_s_phys_addr_from_edid(aux->cec.adap, edid);
>   }
>  unlock:
> + /*
> +  * Update the phys addr for the new CEC adapter. When called
> +  * from drm_dp_cec_register_connector() edid == NULL, so in
> +  * that case the phys addr is just invalidated.
> +  */
> + if (aux->cec.adap && edid) {
> + cec_s_phys_addr_from_edid(aux->cec.adap, edid);
> + }

And here

>   mutex_unlock(>cec.lock);
>  }
>  EXPORT_SYMBOL(drm_dp_cec_set_edid);
> @@ -418,6 +418,7 @@ EXPORT_SYMBOL(drm_dp_cec_unset_edid);
>   * drm_dp_cec_register_connector() - register a new connector
>   * @aux: DisplayPort AUX channel
>   * @connector: drm connector
> + * @is_mst: set to true if this is an MST branch
>   *
>   * A new connector was registered with associated CEC adapter name and
>   * CEC adapter parent device. After registering the name and parent
> @@ -425,12 +426,13 @@ EXPORT_SYMBOL(drm_dp_cec_unset_edid);
>   * CEC and to register a CEC adapter if that is the case.
>   */
>  void drm_dp_cec_register_connector(struct drm_dp_aux *aux,
> -struct drm_connector *connector)
> +struct drm_connector *connector, bool is_mst)
>  {
>   WARN_ON(aux->cec.adap);
>   if (WARN_ON(!aux->transfer))
>   return;
>   aux->cec.connector = connector;
> + aux->cec.is_mst = is_mst;

Also JFYI, you can also check aux->is_remote, but maybe you've got another
reason for copying this here

Either way:

Reviewed-by: Lyude Paul 

...Also, maybe this is just a coincidence - but do I know your name from
somewhere? Perhaps an IRC community from long ago?

>   INIT_DELAYED_WORK(>cec.unregister_work,
> drm_dp_cec_unregister_work);
>  }
> diff --git a/drivers/gpu/drm/i915/display/intel_dp.c
> b/drivers/gpu/drm/i915/display/intel_dp.c
> index 82b9de274f65..744cb55572f9 100644
> --- a/drivers/gpu/drm/i915/display/intel_dp.c
> +++ b/drivers/gpu/drm/i915/display/intel_dp.c
> @@ -6261,7 +6261,7 @@ intel_dp_connector_register(struct drm_connector
> *connector)
>   intel_dp->aux.dev = connector->kdev;
>   ret = drm_dp_aux_register(_dp->aux);
>   if