[v2,01/26] drm/bridge: allow optionally specifying an owner .odev device

Commit Message

Peter Rosin May 9, 2018, 10:21 p.m. UTC

On 2018-05-09 17:53, Peter Rosin wrote:
> On 2018-05-09 17:08, Andrzej Hajda wrote:
>> On 04.05.2018 15:51, Peter Rosin wrote:
>>> Bridge drivers can now (temporarily, in a transition phase) select if
>>> they want to provide a full owner device or keep just providing an
>>> of_node.
>>>
>>> By providing a full owner device, the bridge drivers no longer need
>>> to provide an of_node since that node is available via the owner
>>> device.
>>>
>>> When all bridge drivers provide an owner device, that will become
>>> mandatory and the .of_node member will be removed.
>>>
>>> Signed-off-by: Peter Rosin <[e-mail]>
>>> ---
>>>  drivers/gpu/drm/drm_bridge.c             | 3 ++-
>>>  drivers/gpu/drm/rockchip/rockchip_lvds.c | 4 +++-
>>
>> What is the reason to put rockchip here? Shouldn't be in separate patch?
> 
> Because the rockchip driver peeks into the bridge struct and all the
> changes in this patch relate to making the new .odev member optional in
> the transition phase, when the bridge can have either a new-style odev
> or an old style of_node.
> 
> I guess this rockchip change could be patch 2, but it has to come first
> after this patch and it makes no sense on its own. Hence, one patch.
> 
> This rockchip_lvds interaction is also present in patch 24/26
> drm/bridge: remove the .of_node member
> 
> I can split them if you want, but I personally don't see the point.

I had a second look, and maybe the series should start with a patch like
this instead, so that the rockchip_lvds.c hunks can be removed from
patch 1/26 and 24/26. That would perhaps be slightly cleaner?

On the other hand, it's orthogonal and this series can be left as is
(with the benefit of me not having to do another iteration and you all
not having another bunch of messages to sift through). The below
patch could easily be (adjusted and) applied later instead. Or not,
since the right fix is to do this with the newfangled static image
format mechanism from Jacopo Mondi, and it might be easier to just do
it right.

State your preference.

Cheers,
Peter

From dee27b36a36acd271459d1489336b56132097425 Mon Sep 17 00:00:00 2001
From: Peter Rosin <[e-mail]>
Date: Wed, 9 May 2018 23:58:24 +0200
Subject: [PATCH] drm/rockchip: lvds: do not dig into the DT of remote bridges

The driver is trying to find the needed "data-mapping" for
interacting with the following bridge in the graphics chain.
But, doing so is bad since it is done w/o regard of the
compatible of the remote bridge, so the value of "data-mapping"
might not mean what this driver assumes. It is also pointless
since no bridge has any documented "data-mapping" DT property
and no dts file show any undocumented use.

Just remove the inappropriate code.

Signed-off-by: Peter Rosin <[e-mail]>
---
 drivers/gpu/drm/rockchip/rockchip_lvds.c | 2 --
 1 file changed, 2 deletions(-)

Comments

Andrzej Hajda May 10, 2018, 7 a.m. UTC | #1

On 10.05.2018 00:21, Peter Rosin wrote:
> On 2018-05-09 17:53, Peter Rosin wrote:
>> On 2018-05-09 17:08, Andrzej Hajda wrote:
>>> On 04.05.2018 15:51, Peter Rosin wrote:
>>>> Bridge drivers can now (temporarily, in a transition phase) select if
>>>> they want to provide a full owner device or keep just providing an
>>>> of_node.
>>>>
>>>> By providing a full owner device, the bridge drivers no longer need
>>>> to provide an of_node since that node is available via the owner
>>>> device.
>>>>
>>>> When all bridge drivers provide an owner device, that will become
>>>> mandatory and the .of_node member will be removed.
>>>>
>>>> Signed-off-by: Peter Rosin <[e-mail]>
>>>> ---
>>>>  drivers/gpu/drm/drm_bridge.c             | 3 ++-
>>>>  drivers/gpu/drm/rockchip/rockchip_lvds.c | 4 +++-
>>> What is the reason to put rockchip here? Shouldn't be in separate patch?
>> Because the rockchip driver peeks into the bridge struct and all the
>> changes in this patch relate to making the new .odev member optional in
>> the transition phase, when the bridge can have either a new-style odev
>> or an old style of_node.
>>
>> I guess this rockchip change could be patch 2, but it has to come first
>> after this patch and it makes no sense on its own. Hence, one patch.
>>
>> This rockchip_lvds interaction is also present in patch 24/26
>> drm/bridge: remove the .of_node member
>>
>> I can split them if you want, but I personally don't see the point.
> I had a second look, and maybe the series should start with a patch like
> this instead, so that the rockchip_lvds.c hunks can be removed from
> patch 1/26 and 24/26. That would perhaps be slightly cleaner?
>
> On the other hand, it's orthogonal and this series can be left as is
> (with the benefit of me not having to do another iteration and you all
> not having another bunch of messages to sift through). The below
> patch could easily be (adjusted and) applied later instead. Or not,
> since the right fix is to do this with the newfangled static image
> format mechanism from Jacopo Mondi, and it might be easier to just do
> it right.
>
> State your preference.

For me the current version is OK, it maybe lacks explanation why do you
need to touch rockchip, from my PoV it did not seem so obvious.
Somebody should fix rockchip to use Jacopo's approach instead of
violating abstractions, but this is another story.

With or without added missing explanation:

Reviewed-by: Andrzej Hajda <[e-mail]>

 --
Regards
Andrzej


>
> Cheers,
> Peter
>
> >From dee27b36a36acd271459d1489336b56132097425 Mon Sep 17 00:00:00 2001
> From: Peter Rosin <[e-mail]>
> Date: Wed, 9 May 2018 23:58:24 +0200
> Subject: [PATCH] drm/rockchip: lvds: do not dig into the DT of remote bridges
>
> The driver is trying to find the needed "data-mapping" for
> interacting with the following bridge in the graphics chain.
> But, doing so is bad since it is done w/o regard of the
> compatible of the remote bridge, so the value of "data-mapping"
> might not mean what this driver assumes. It is also pointless
> since no bridge has any documented "data-mapping" DT property
> and no dts file show any undocumented use.
>
> Just remove the inappropriate code.
>
> Signed-off-by: Peter Rosin <[e-mail]>
> ---
>  drivers/gpu/drm/rockchip/rockchip_lvds.c | 2 --
>  1 file changed, 2 deletions(-)
>
> diff --git a/drivers/gpu/drm/rockchip/rockchip_lvds.c b/drivers/gpu/drm/rockchip/rockchip_lvds.c
> index 4bd94b167d2c..fa3f4bf9712f 100644
> --- a/drivers/gpu/drm/rockchip/rockchip_lvds.c
> +++ b/drivers/gpu/drm/rockchip/rockchip_lvds.c
> @@ -377,8 +377,6 @@ static int rockchip_lvds_bind(struct device *dev, struct device *master,
>  	}
>  	if (lvds->panel)
>  		remote = lvds->panel->dev->of_node;
> -	else
> -		remote = lvds->bridge->of_node;
>  	if (of_property_read_string(dev->of_node, "rockchip,output", &name))
>  		/* default set it as output rgb */
>  		lvds->output = DISPLAY_OUTPUT_RGB;

Patch

diff --git a/drivers/gpu/drm/rockchip/rockchip_lvds.c b/drivers/gpu/drm/rockchip/rockchip_lvds.c
index 4bd94b167d2c..fa3f4bf9712f 100644
--- a/drivers/gpu/drm/rockchip/rockchip_lvds.c
+++ b/drivers/gpu/drm/rockchip/rockchip_lvds.c
@@ -377,8 +377,6 @@  static int rockchip_lvds_bind(struct device *dev, struct device *master,
 	}
 	if (lvds->panel)
 		remote = lvds->panel->dev->of_node;
-	else
-		remote = lvds->bridge->of_node;
 	if (of_property_read_string(dev->of_node, "rockchip,output", &name))
 		/* default set it as output rgb */
 		lvds->output = DISPLAY_OUTPUT_RGB;