[PATCH AUTOSEL 6.11 08/15] drm: display: Set fwnode for aux bus devices

[PATCH AUTOSEL 6.11 08/15] drm: display: Set fwnode for aux bus devices

[Sasha Levin]

From: Saravana Kannan <saravanak@google.com>

[ Upstream commit fe2e59aa5d7077c5c564d55b7e2997e83710c314 ]

fwnode needs to be set for a device for fw_devlink to be able to
track/enforce its dependencies correctly. Without this, you'll see error
messages like this when the supplier has probed and tries to make sure
all its fwnode consumers are linked to it using device links:

mediatek-drm-dp 1c500000.edp-tx: Failed to create device link (0x180) with backlight-lcd0

Reported-by: Nícolas F. R. A. Prado <nfraprado@collabora.com>
Closes: https://lore.kernel.org/all/7b995947-4540-4b17-872e-e107adca4598@notapiano/
Tested-by: Nícolas F. R. A. Prado <nfraprado@collabora.com>
Signed-off-by: Saravana Kannan <saravanak@google.com>
Reviewed-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>
Reviewed-by: Thierry Reding <treding@nvidia.com>
Tested-by: AngeloGioacchino Del Regno <angelogioacchino.delregno@collabora.com>
Link: https://lore.kernel.org/r/20241024061347.1771063-2-saravanak@google.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 drivers/gpu/drm/display/drm_dp_aux_bus.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/gpu/drm/display/drm_dp_aux_bus.c b/drivers/gpu/drm/display/drm_dp_aux_bus.c
index d810529ebfb6e..ec7eac6b595f7 100644
--- a/drivers/gpu/drm/display/drm_dp_aux_bus.c
+++ b/drivers/gpu/drm/display/drm_dp_aux_bus.c
@@ -292,7 +292,7 @@ int of_dp_aux_populate_bus(struct drm_dp_aux *aux,
 	aux_ep->dev.parent = aux->dev;
 	aux_ep->dev.bus = &dp_aux_bus_type;
 	aux_ep->dev.type = &dp_aux_device_type_type;
-	aux_ep->dev.of_node = of_node_get(np);
+	device_set_node(&aux_ep->dev, of_fwnode_handle(of_node_get(np)));
 	dev_set_name(&aux_ep->dev, "aux-%s", dev_name(aux->dev));
 
 	ret = device_register(&aux_ep->dev);
-- 
2.43.0

Re: [PATCH AUTOSEL 6.11 08/15] drm: display: Set fwnode for aux bus devices

[Saravana Kannan]

On Wed, Dec 4, 2024 at 3:29 PM Sasha Levin <sashal@kernel.org> wrote:
>
> From: Saravana Kannan <saravanak@google.com>
>
> [ Upstream commit fe2e59aa5d7077c5c564d55b7e2997e83710c314 ]
>
> fwnode needs to be set for a device for fw_devlink to be able to
> track/enforce its dependencies correctly. Without this, you'll see error
> messages like this when the supplier has probed and tries to make sure
> all its fwnode consumers are linked to it using device links:
>
> mediatek-drm-dp 1c500000.edp-tx: Failed to create device link (0x180) with backlight-lcd0
>
> Reported-by: Nícolas F. R. A. Prado <nfraprado@collabora.com>
> Closes: https://lore.kernel.org/all/7b995947-4540-4b17-872e-e107adca4598@notapiano/
> Tested-by: Nícolas F. R. A. Prado <nfraprado@collabora.com>
> Signed-off-by: Saravana Kannan <saravanak@google.com>
> Reviewed-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>
> Reviewed-by: Thierry Reding <treding@nvidia.com>
> Tested-by: AngeloGioacchino Del Regno <angelogioacchino.delregno@collabora.com>
> Link: https://lore.kernel.org/r/20241024061347.1771063-2-saravanak@google.com
> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
> Signed-off-by: Sasha Levin <sashal@kernel.org>

As mentioned in the original cover letter:

PSA: Do not pull any of these patches into stable kernels. fw_devlink
had a lot of changes that landed in the last year. It's hard to ensure
cherry-picks have picked up all the dependencies correctly. If any of
these really need to get cherry-picked into stable kernels, cc me and
wait for my explicit Ack.

Is there a pressing need for this in 4.19?

-Saravana

> ---
>  drivers/gpu/drm/display/drm_dp_aux_bus.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/drivers/gpu/drm/display/drm_dp_aux_bus.c b/drivers/gpu/drm/display/drm_dp_aux_bus.c
> index d810529ebfb6e..ec7eac6b595f7 100644
> --- a/drivers/gpu/drm/display/drm_dp_aux_bus.c
> +++ b/drivers/gpu/drm/display/drm_dp_aux_bus.c
> @@ -292,7 +292,7 @@ int of_dp_aux_populate_bus(struct drm_dp_aux *aux,
>         aux_ep->dev.parent = aux->dev;
>         aux_ep->dev.bus = &dp_aux_bus_type;
>         aux_ep->dev.type = &dp_aux_device_type_type;
> -       aux_ep->dev.of_node = of_node_get(np);
> +       device_set_node(&aux_ep->dev, of_fwnode_handle(of_node_get(np)));
>         dev_set_name(&aux_ep->dev, "aux-%s", dev_name(aux->dev));
>
>         ret = device_register(&aux_ep->dev);
> --
> 2.43.0
>

Re: [PATCH AUTOSEL 6.11 08/15] drm: display: Set fwnode for aux bus devices

[Saravana Kannan]

On Thu, Dec 5, 2024 at 4:06 PM Saravana Kannan <saravanak@google.com> wrote:
>
> On Wed, Dec 4, 2024 at 3:29 PM Sasha Levin <sashal@kernel.org> wrote:
> >
> > From: Saravana Kannan <saravanak@google.com>
> >
> > [ Upstream commit fe2e59aa5d7077c5c564d55b7e2997e83710c314 ]
> >
> > fwnode needs to be set for a device for fw_devlink to be able to
> > track/enforce its dependencies correctly. Without this, you'll see error
> > messages like this when the supplier has probed and tries to make sure
> > all its fwnode consumers are linked to it using device links:
> >
> > mediatek-drm-dp 1c500000.edp-tx: Failed to create device link (0x180) with backlight-lcd0
> >
> > Reported-by: Nícolas F. R. A. Prado <nfraprado@collabora.com>
> > Closes: https://lore.kernel.org/all/7b995947-4540-4b17-872e-e107adca4598@notapiano/
> > Tested-by: Nícolas F. R. A. Prado <nfraprado@collabora.com>
> > Signed-off-by: Saravana Kannan <saravanak@google.com>
> > Reviewed-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>
> > Reviewed-by: Thierry Reding <treding@nvidia.com>
> > Tested-by: AngeloGioacchino Del Regno <angelogioacchino.delregno@collabora.com>
> > Link: https://lore.kernel.org/r/20241024061347.1771063-2-saravanak@google.com
> > Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
> > Signed-off-by: Sasha Levin <sashal@kernel.org>
>
> As mentioned in the original cover letter:
>
> PSA: Do not pull any of these patches into stable kernels. fw_devlink
> had a lot of changes that landed in the last year. It's hard to ensure
> cherry-picks have picked up all the dependencies correctly. If any of
> these really need to get cherry-picked into stable kernels, cc me and
> wait for my explicit Ack.
>
> Is there a pressing need for this in 4.19?

I copy pasted this into several replies. In all those cases I meant
the kernel version mentioned in the subject.

-Saravana

>
> -Saravana
>
> > ---
> >  drivers/gpu/drm/display/drm_dp_aux_bus.c | 2 +-
> >  1 file changed, 1 insertion(+), 1 deletion(-)
> >
> > diff --git a/drivers/gpu/drm/display/drm_dp_aux_bus.c b/drivers/gpu/drm/display/drm_dp_aux_bus.c
> > index d810529ebfb6e..ec7eac6b595f7 100644
> > --- a/drivers/gpu/drm/display/drm_dp_aux_bus.c
> > +++ b/drivers/gpu/drm/display/drm_dp_aux_bus.c
> > @@ -292,7 +292,7 @@ int of_dp_aux_populate_bus(struct drm_dp_aux *aux,
> >         aux_ep->dev.parent = aux->dev;
> >         aux_ep->dev.bus = &dp_aux_bus_type;
> >         aux_ep->dev.type = &dp_aux_device_type_type;
> > -       aux_ep->dev.of_node = of_node_get(np);
> > +       device_set_node(&aux_ep->dev, of_fwnode_handle(of_node_get(np)));
> >         dev_set_name(&aux_ep->dev, "aux-%s", dev_name(aux->dev));
> >
> >         ret = device_register(&aux_ep->dev);
> > --
> > 2.43.0
> >

Re: [PATCH AUTOSEL 6.11 08/15] drm: display: Set fwnode for aux bus devices

[Sasha Levin]

On Thu, Dec 05, 2024 at 04:07:45PM -0800, Saravana Kannan wrote:
>On Thu, Dec 5, 2024 at 4:06 PM Saravana Kannan <saravanak@google.com> wrote:
>>
>> On Wed, Dec 4, 2024 at 3:29 PM Sasha Levin <sashal@kernel.org> wrote:
>> >
>> > From: Saravana Kannan <saravanak@google.com>
>> >
>> > [ Upstream commit fe2e59aa5d7077c5c564d55b7e2997e83710c314 ]
>> >
>> > fwnode needs to be set for a device for fw_devlink to be able to
>> > track/enforce its dependencies correctly. Without this, you'll see error
>> > messages like this when the supplier has probed and tries to make sure
>> > all its fwnode consumers are linked to it using device links:
>> >
>> > mediatek-drm-dp 1c500000.edp-tx: Failed to create device link (0x180) with backlight-lcd0
>> >
>> > Reported-by: Nícolas F. R. A. Prado <nfraprado@collabora.com>
>> > Closes: https://lore.kernel.org/all/7b995947-4540-4b17-872e-e107adca4598@notapiano/
>> > Tested-by: Nícolas F. R. A. Prado <nfraprado@collabora.com>
>> > Signed-off-by: Saravana Kannan <saravanak@google.com>
>> > Reviewed-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>
>> > Reviewed-by: Thierry Reding <treding@nvidia.com>
>> > Tested-by: AngeloGioacchino Del Regno <angelogioacchino.delregno@collabora.com>
>> > Link: https://lore.kernel.org/r/20241024061347.1771063-2-saravanak@google.com
>> > Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
>> > Signed-off-by: Sasha Levin <sashal@kernel.org>
>>
>> As mentioned in the original cover letter:
>>
>> PSA: Do not pull any of these patches into stable kernels. fw_devlink
>> had a lot of changes that landed in the last year. It's hard to ensure
>> cherry-picks have picked up all the dependencies correctly. If any of
>> these really need to get cherry-picked into stable kernels, cc me and
>> wait for my explicit Ack.
>>
>> Is there a pressing need for this in 4.19?
>
>I copy pasted this into several replies. In all those cases I meant
>the kernel version mentioned in the subject.

I'll drop this and the other patch you've pointed out, thanks!

-- 
Thanks,
Sasha