diff mbox series

[1/3] drm/omap: Prepare DSS for probing without legacy platform data

Message ID 20200224191230.30972-2-tony@atomide.com (mailing list archive)
State New, archived
Headers show
Series ti-sysc changes for probing DSS with dts data | expand

Commit Message

Tony Lindgren Feb. 24, 2020, 7:12 p.m. UTC
In order to probe display subsystem (DSS) components with ti-sysc
interconnect target module without legacy platform data and using
devicetree, we need to update dss probing a bit.

In the device tree, we will be defining the data also for the interconnect
target modules as DSS really is a private interconnect. There is some
information about that in 4460 TRM in "Figure 10-3. DSS Integration" for
example where it mentions "32-bit interconnect (SLX)".

The changes we need to make are:

1. Parse also device tree subnodes for the compatible property fixup

2. Update the component code to consider device tree subnodes

Cc: dri-devel@lists.freedesktop.org
Cc: Jyri Sarha <jsarha@ti.com>
Cc: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Cc: Tomi Valkeinen <tomi.valkeinen@ti.com>
Signed-off-by: Tony Lindgren <tony@atomide.com>
---

This is needed for dropping DSS platform data that I'll be posting
seprately. If this looks OK, can you guys please test and ack?

---
 drivers/gpu/drm/omapdrm/dss/dss.c             | 25 ++++++++++++++++---
 .../gpu/drm/omapdrm/dss/omapdss-boot-init.c   | 25 +++++++++++++------
 2 files changed, 39 insertions(+), 11 deletions(-)

Comments

Laurent Pinchart Feb. 24, 2020, 9:40 p.m. UTC | #1
Hi Tony,

Thank you for the patch.

On Mon, Feb 24, 2020 at 11:12:28AM -0800, Tony Lindgren wrote:
> In order to probe display subsystem (DSS) components with ti-sysc
> interconnect target module without legacy platform data and using
> devicetree, we need to update dss probing a bit.
> 
> In the device tree, we will be defining the data also for the interconnect
> target modules as DSS really is a private interconnect. There is some
> information about that in 4460 TRM in "Figure 10-3. DSS Integration" for
> example where it mentions "32-bit interconnect (SLX)".
> 
> The changes we need to make are:
> 
> 1. Parse also device tree subnodes for the compatible property fixup
> 
> 2. Update the component code to consider device tree subnodes
> 
> Cc: dri-devel@lists.freedesktop.org
> Cc: Jyri Sarha <jsarha@ti.com>
> Cc: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
> Cc: Tomi Valkeinen <tomi.valkeinen@ti.com>
> Signed-off-by: Tony Lindgren <tony@atomide.com>

Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>

> ---
> 
> This is needed for dropping DSS platform data that I'll be posting
> seprately. If this looks OK, can you guys please test and ack?
> 
> ---
>  drivers/gpu/drm/omapdrm/dss/dss.c             | 25 ++++++++++++++++---
>  .../gpu/drm/omapdrm/dss/omapdss-boot-init.c   | 25 +++++++++++++------
>  2 files changed, 39 insertions(+), 11 deletions(-)
> 
> diff --git a/drivers/gpu/drm/omapdrm/dss/dss.c b/drivers/gpu/drm/omapdrm/dss/dss.c
> --- a/drivers/gpu/drm/omapdrm/dss/dss.c
> +++ b/drivers/gpu/drm/omapdrm/dss/dss.c
> @@ -1339,9 +1339,15 @@ static int dss_component_compare(struct device *dev, void *data)
>  	return dev == child;
>  }
>  
> +struct dss_component_match_data {
> +	struct device *dev;
> +	struct component_match **match;
> +};
> +
>  static int dss_add_child_component(struct device *dev, void *data)
>  {
> -	struct component_match **match = data;
> +	struct dss_component_match_data *cmatch = data;
> +	struct component_match **match = cmatch->match;
>  
>  	/*
>  	 * HACK
> @@ -1352,7 +1358,17 @@ static int dss_add_child_component(struct device *dev, void *data)
>  	if (strstr(dev_name(dev), "rfbi"))
>  		return 0;
>  
> -	component_match_add(dev->parent, match, dss_component_compare, dev);
> +	/*
> +	 * Handle possible interconnect target modules defined within the DSS.
> +	 * The DSS components can be children of an interconnect target module
> +	 * after the device tree has been updated for the module data.
> +	 * See also omapdss_boot_init() for compatible fixup.
> +	 */
> +	if (strstr(dev_name(dev), "target-module"))
> +		return device_for_each_child(dev, cmatch,
> +					     dss_add_child_component);
> +
> +	component_match_add(cmatch->dev, match, dss_component_compare, dev);
>  
>  	return 0;
>  }
> @@ -1395,6 +1411,7 @@ static int dss_probe_hardware(struct dss_device *dss)
>  static int dss_probe(struct platform_device *pdev)
>  {
>  	const struct soc_device_attribute *soc;
> +	struct dss_component_match_data cmatch;
>  	struct component_match *match = NULL;
>  	struct resource *dss_mem;
>  	struct dss_device *dss;
> @@ -1472,7 +1489,9 @@ static int dss_probe(struct platform_device *pdev)
>  
>  	omapdss_gather_components(&pdev->dev);
>  
> -	device_for_each_child(&pdev->dev, &match, dss_add_child_component);
> +	cmatch.dev = &pdev->dev;
> +	cmatch.match = &match;
> +	device_for_each_child(&pdev->dev, &cmatch, dss_add_child_component);
>  
>  	r = component_master_add_with_match(&pdev->dev, &dss_component_ops, match);
>  	if (r)
> diff --git a/drivers/gpu/drm/omapdrm/dss/omapdss-boot-init.c b/drivers/gpu/drm/omapdrm/dss/omapdss-boot-init.c
> --- a/drivers/gpu/drm/omapdrm/dss/omapdss-boot-init.c
> +++ b/drivers/gpu/drm/omapdrm/dss/omapdss-boot-init.c
> @@ -183,9 +183,24 @@ static const struct of_device_id omapdss_of_fixups_whitelist[] __initconst = {
>  	{},
>  };
>  
> +static void __init omapdss_find_children(struct device_node *np)
> +{
> +	struct device_node *child;
> +
> +	for_each_available_child_of_node(np, child) {
> +		if (!of_find_property(child, "compatible", NULL))
> +			continue;
> +
> +		omapdss_walk_device(child, true);
> +
> +		if (of_device_is_compatible(child, "ti,sysc"))
> +			omapdss_find_children(child);
> +	}
> +}
> +
>  static int __init omapdss_boot_init(void)
>  {
> -	struct device_node *dss, *child;
> +	struct device_node *dss;
>  
>  	INIT_LIST_HEAD(&dss_conv_list);
>  
> @@ -195,13 +210,7 @@ static int __init omapdss_boot_init(void)
>  		return 0;
>  
>  	omapdss_walk_device(dss, true);
> -
> -	for_each_available_child_of_node(dss, child) {
> -		if (!of_find_property(child, "compatible", NULL))
> -			continue;
> -
> -		omapdss_walk_device(child, true);
> -	}
> +	omapdss_find_children(dss);
>  
>  	while (!list_empty(&dss_conv_list)) {
>  		struct dss_conv_node *n;
Sebastian Reichel Feb. 24, 2020, 11:31 p.m. UTC | #2
Hi,

On Mon, Feb 24, 2020 at 11:12:28AM -0800, Tony Lindgren wrote:
> In order to probe display subsystem (DSS) components with ti-sysc
> interconnect target module without legacy platform data and using
> devicetree, we need to update dss probing a bit.
> 
> In the device tree, we will be defining the data also for the interconnect
> target modules as DSS really is a private interconnect. There is some
> information about that in 4460 TRM in "Figure 10-3. DSS Integration" for
> example where it mentions "32-bit interconnect (SLX)".
> 
> The changes we need to make are:
> 
> 1. Parse also device tree subnodes for the compatible property fixup
> 
> 2. Update the component code to consider device tree subnodes
> 
> Cc: dri-devel@lists.freedesktop.org
> Cc: Jyri Sarha <jsarha@ti.com>
> Cc: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
> Cc: Tomi Valkeinen <tomi.valkeinen@ti.com>
> Signed-off-by: Tony Lindgren <tony@atomide.com>
> ---
> 
> This is needed for dropping DSS platform data that I'll be posting
> seprately. If this looks OK, can you guys please test and ack?
> 
> ---

Reviewed-by: Sebastian Reichel <sebastian.reichel@collabora.com>

FWIW, I dropped omapdss-boot-init.c in my patch series updating DSI
code to use common panel infrastructure, so this will conflict.

-- Sebastian

>  drivers/gpu/drm/omapdrm/dss/dss.c             | 25 ++++++++++++++++---
>  .../gpu/drm/omapdrm/dss/omapdss-boot-init.c   | 25 +++++++++++++------
>  2 files changed, 39 insertions(+), 11 deletions(-)
> 
> diff --git a/drivers/gpu/drm/omapdrm/dss/dss.c b/drivers/gpu/drm/omapdrm/dss/dss.c
> --- a/drivers/gpu/drm/omapdrm/dss/dss.c
> +++ b/drivers/gpu/drm/omapdrm/dss/dss.c
> @@ -1339,9 +1339,15 @@ static int dss_component_compare(struct device *dev, void *data)
>  	return dev == child;
>  }
>  
> +struct dss_component_match_data {
> +	struct device *dev;
> +	struct component_match **match;
> +};
> +
>  static int dss_add_child_component(struct device *dev, void *data)
>  {
> -	struct component_match **match = data;
> +	struct dss_component_match_data *cmatch = data;
> +	struct component_match **match = cmatch->match;
>  
>  	/*
>  	 * HACK
> @@ -1352,7 +1358,17 @@ static int dss_add_child_component(struct device *dev, void *data)
>  	if (strstr(dev_name(dev), "rfbi"))
>  		return 0;
>  
> -	component_match_add(dev->parent, match, dss_component_compare, dev);
> +	/*
> +	 * Handle possible interconnect target modules defined within the DSS.
> +	 * The DSS components can be children of an interconnect target module
> +	 * after the device tree has been updated for the module data.
> +	 * See also omapdss_boot_init() for compatible fixup.
> +	 */
> +	if (strstr(dev_name(dev), "target-module"))
> +		return device_for_each_child(dev, cmatch,
> +					     dss_add_child_component);
> +
> +	component_match_add(cmatch->dev, match, dss_component_compare, dev);
>  
>  	return 0;
>  }
> @@ -1395,6 +1411,7 @@ static int dss_probe_hardware(struct dss_device *dss)
>  static int dss_probe(struct platform_device *pdev)
>  {
>  	const struct soc_device_attribute *soc;
> +	struct dss_component_match_data cmatch;
>  	struct component_match *match = NULL;
>  	struct resource *dss_mem;
>  	struct dss_device *dss;
> @@ -1472,7 +1489,9 @@ static int dss_probe(struct platform_device *pdev)
>  
>  	omapdss_gather_components(&pdev->dev);
>  
> -	device_for_each_child(&pdev->dev, &match, dss_add_child_component);
> +	cmatch.dev = &pdev->dev;
> +	cmatch.match = &match;
> +	device_for_each_child(&pdev->dev, &cmatch, dss_add_child_component);
>  
>  	r = component_master_add_with_match(&pdev->dev, &dss_component_ops, match);
>  	if (r)
> diff --git a/drivers/gpu/drm/omapdrm/dss/omapdss-boot-init.c b/drivers/gpu/drm/omapdrm/dss/omapdss-boot-init.c
> --- a/drivers/gpu/drm/omapdrm/dss/omapdss-boot-init.c
> +++ b/drivers/gpu/drm/omapdrm/dss/omapdss-boot-init.c
> @@ -183,9 +183,24 @@ static const struct of_device_id omapdss_of_fixups_whitelist[] __initconst = {
>  	{},
>  };
>  
> +static void __init omapdss_find_children(struct device_node *np)
> +{
> +	struct device_node *child;
> +
> +	for_each_available_child_of_node(np, child) {
> +		if (!of_find_property(child, "compatible", NULL))
> +			continue;
> +
> +		omapdss_walk_device(child, true);
> +
> +		if (of_device_is_compatible(child, "ti,sysc"))
> +			omapdss_find_children(child);
> +	}
> +}
> +
>  static int __init omapdss_boot_init(void)
>  {
> -	struct device_node *dss, *child;
> +	struct device_node *dss;
>  
>  	INIT_LIST_HEAD(&dss_conv_list);
>  
> @@ -195,13 +210,7 @@ static int __init omapdss_boot_init(void)
>  		return 0;
>  
>  	omapdss_walk_device(dss, true);
> -
> -	for_each_available_child_of_node(dss, child) {
> -		if (!of_find_property(child, "compatible", NULL))
> -			continue;
> -
> -		omapdss_walk_device(child, true);
> -	}
> +	omapdss_find_children(dss);
>  
>  	while (!list_empty(&dss_conv_list)) {
>  		struct dss_conv_node *n;
> -- 
> 2.25.1
Tony Lindgren Feb. 24, 2020, 11:43 p.m. UTC | #3
* Sebastian Reichel <sre@kernel.org> [200224 23:32]:
> Hi,
> 
> On Mon, Feb 24, 2020 at 11:12:28AM -0800, Tony Lindgren wrote:
> > In order to probe display subsystem (DSS) components with ti-sysc
> > interconnect target module without legacy platform data and using
> > devicetree, we need to update dss probing a bit.
> > 
> > In the device tree, we will be defining the data also for the interconnect
> > target modules as DSS really is a private interconnect. There is some
> > information about that in 4460 TRM in "Figure 10-3. DSS Integration" for
> > example where it mentions "32-bit interconnect (SLX)".
> > 
> > The changes we need to make are:
> > 
> > 1. Parse also device tree subnodes for the compatible property fixup
> > 
> > 2. Update the component code to consider device tree subnodes
> > 
> > Cc: dri-devel@lists.freedesktop.org
> > Cc: Jyri Sarha <jsarha@ti.com>
> > Cc: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
> > Cc: Tomi Valkeinen <tomi.valkeinen@ti.com>
> > Signed-off-by: Tony Lindgren <tony@atomide.com>
> > ---
> > 
> > This is needed for dropping DSS platform data that I'll be posting
> > seprately. If this looks OK, can you guys please test and ack?
> > 
> > ---
> 
> Reviewed-by: Sebastian Reichel <sebastian.reichel@collabora.com>
> 
> FWIW, I dropped omapdss-boot-init.c in my patch series updating DSI
> code to use common panel infrastructure, so this will conflict.

Hey that's great :) Sounds like we can set up an immutable branch
for just this $subject patch against v5.6-rc1 to resolve the
conflict. I can set it up for Tomi or Tomi can set it up for me,
whichever Tomi prefers.

Regards,

Tony
Tony Lindgren Feb. 27, 2020, 5:44 p.m. UTC | #4
Tomi,

* Tony Lindgren <tony@atomide.com> [200224 23:44]:
> * Sebastian Reichel <sre@kernel.org> [200224 23:32]:
> > Hi,
> > 
> > On Mon, Feb 24, 2020 at 11:12:28AM -0800, Tony Lindgren wrote:
> > > In order to probe display subsystem (DSS) components with ti-sysc
> > > interconnect target module without legacy platform data and using
> > > devicetree, we need to update dss probing a bit.
> > > 
> > > In the device tree, we will be defining the data also for the interconnect
> > > target modules as DSS really is a private interconnect. There is some
> > > information about that in 4460 TRM in "Figure 10-3. DSS Integration" for
> > > example where it mentions "32-bit interconnect (SLX)".
> > > 
> > > The changes we need to make are:
> > > 
> > > 1. Parse also device tree subnodes for the compatible property fixup
> > > 
> > > 2. Update the component code to consider device tree subnodes
> > > 
> > > Cc: dri-devel@lists.freedesktop.org
> > > Cc: Jyri Sarha <jsarha@ti.com>
> > > Cc: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
> > > Cc: Tomi Valkeinen <tomi.valkeinen@ti.com>
> > > Signed-off-by: Tony Lindgren <tony@atomide.com>
> > > ---
> > > 
> > > This is needed for dropping DSS platform data that I'll be posting
> > > seprately. If this looks OK, can you guys please test and ack?
> > > 
> > > ---
> > 
> > Reviewed-by: Sebastian Reichel <sebastian.reichel@collabora.com>
> > 
> > FWIW, I dropped omapdss-boot-init.c in my patch series updating DSI
> > code to use common panel infrastructure, so this will conflict.
> 
> Hey that's great :) Sounds like we can set up an immutable branch
> for just this $subject patch against v5.6-rc1 to resolve the
> conflict. I can set it up for Tomi or Tomi can set it up for me,
> whichever Tomi prefers.

Do you want me to send you a pull request for just this one patch
against v5.6-rc1?

Regards,

Tony
Tomi Valkeinen March 2, 2020, 10:28 a.m. UTC | #5
On 27/02/2020 19:44, Tony Lindgren wrote:

>>> FWIW, I dropped omapdss-boot-init.c in my patch series updating DSI
>>> code to use common panel infrastructure, so this will conflict.
>>
>> Hey that's great :) Sounds like we can set up an immutable branch
>> for just this $subject patch against v5.6-rc1 to resolve the
>> conflict. I can set it up for Tomi or Tomi can set it up for me,
>> whichever Tomi prefers.
> 
> Do you want me to send you a pull request for just this one patch
> against v5.6-rc1?

It's probably easier if Sebastian drops the removal patch, and instead creates a patch that removes 
the panel-dsi-cm from omapdss_of_fixups_whitelist. That change should not conflict, and effectively 
makes the omapdss-boot-init.c a no-op.

We can then remove the file later.

  Tomi
Tony Lindgren March 2, 2020, 3:01 p.m. UTC | #6
* Tomi Valkeinen <tomi.valkeinen@ti.com> [200302 10:29]:
> On 27/02/2020 19:44, Tony Lindgren wrote:
> 
> > > > FWIW, I dropped omapdss-boot-init.c in my patch series updating DSI
> > > > code to use common panel infrastructure, so this will conflict.
> > > 
> > > Hey that's great :) Sounds like we can set up an immutable branch
> > > for just this $subject patch against v5.6-rc1 to resolve the
> > > conflict. I can set it up for Tomi or Tomi can set it up for me,
> > > whichever Tomi prefers.
> > 
> > Do you want me to send you a pull request for just this one patch
> > against v5.6-rc1?
> 
> It's probably easier if Sebastian drops the removal patch, and instead
> creates a patch that removes the panel-dsi-cm from
> omapdss_of_fixups_whitelist. That change should not conflict, and
> effectively makes the omapdss-boot-init.c a no-op.
> 
> We can then remove the file later.

OK for resolving the merge commit that works too.

Tomi, so do you care to ack the $subject patch though so I can set
up an immutable branch for us for the $subject patch?

Or Tomi, do you want to set up an immutable branch for me for the
$subject patch?

Regards,

Tony
Tomi Valkeinen March 3, 2020, 9:18 a.m. UTC | #7
On 24/02/2020 21:12, Tony Lindgren wrote:
> In order to probe display subsystem (DSS) components with ti-sysc
> interconnect target module without legacy platform data and using
> devicetree, we need to update dss probing a bit.
> 
> In the device tree, we will be defining the data also for the interconnect
> target modules as DSS really is a private interconnect. There is some
> information about that in 4460 TRM in "Figure 10-3. DSS Integration" for
> example where it mentions "32-bit interconnect (SLX)".
> 
> The changes we need to make are:
> 
> 1. Parse also device tree subnodes for the compatible property fixup
> 
> 2. Update the component code to consider device tree subnodes
> 
> Cc: dri-devel@lists.freedesktop.org
> Cc: Jyri Sarha <jsarha@ti.com>
> Cc: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
> Cc: Tomi Valkeinen <tomi.valkeinen@ti.com>
> Signed-off-by: Tony Lindgren <tony@atomide.com>
> ---
> 
> This is needed for dropping DSS platform data that I'll be posting
> seprately. If this looks OK, can you guys please test and ack?
> 
> ---
>   drivers/gpu/drm/omapdrm/dss/dss.c             | 25 ++++++++++++++++---
>   .../gpu/drm/omapdrm/dss/omapdss-boot-init.c   | 25 +++++++++++++------
>   2 files changed, 39 insertions(+), 11 deletions(-)

Reviewed-by: Tomi Valkeinen <tomi.valkeinen@ti.com>

This doesn't conflict with drm-next (with Laurent's recent patches), so it should be fine for you to 
have this in your branch.

And not a biggie, but I wonder if the changes to these two files should be in separate patches, due 
to omapdss-boot-init going away. Well, probably doesn't matter.

  Tomi
Tony Lindgren March 3, 2020, 3:36 p.m. UTC | #8
* Tomi Valkeinen <tomi.valkeinen@ti.com> [200303 09:19]:
> On 24/02/2020 21:12, Tony Lindgren wrote:
> > In order to probe display subsystem (DSS) components with ti-sysc
> > interconnect target module without legacy platform data and using
> > devicetree, we need to update dss probing a bit.
> > 
> > In the device tree, we will be defining the data also for the interconnect
> > target modules as DSS really is a private interconnect. There is some
> > information about that in 4460 TRM in "Figure 10-3. DSS Integration" for
> > example where it mentions "32-bit interconnect (SLX)".
> > 
> > The changes we need to make are:
> > 
> > 1. Parse also device tree subnodes for the compatible property fixup
> > 
> > 2. Update the component code to consider device tree subnodes
> > 
> > Cc: dri-devel@lists.freedesktop.org
> > Cc: Jyri Sarha <jsarha@ti.com>
> > Cc: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
> > Cc: Tomi Valkeinen <tomi.valkeinen@ti.com>
> > Signed-off-by: Tony Lindgren <tony@atomide.com>
> > ---
> > 
> > This is needed for dropping DSS platform data that I'll be posting
> > seprately. If this looks OK, can you guys please test and ack?
> > 
> > ---
> >   drivers/gpu/drm/omapdrm/dss/dss.c             | 25 ++++++++++++++++---
> >   .../gpu/drm/omapdrm/dss/omapdss-boot-init.c   | 25 +++++++++++++------
> >   2 files changed, 39 insertions(+), 11 deletions(-)
> 
> Reviewed-by: Tomi Valkeinen <tomi.valkeinen@ti.com>
> 
> This doesn't conflict with drm-next (with Laurent's recent patches), so it
> should be fine for you to have this in your branch.

OK thank you. I've pushed out omap-for-v5.7/dss-probe which has just
this commit against v5.6-rc1 [0][1]. Let's consider commit cef766300353
("drm/omap: Prepare DSS for probing without legacy platform data")
immutable so we can both merge it in as needed.

I have not added any tag yet as it seems that we could add also
apply Sebastian's few preparatory dts changes to this branch when
ready.

> And not a biggie, but I wonder if the changes to these two files should be
> in separate patches, due to omapdss-boot-init going away. Well, probably
> doesn't matter.

Hmm yeah good reason to put every change into a seprate patch
for future. I really did not expect this to conflict with anything
after years of no changes :)

Regards,

Tony

[0] git://git.kernel.org/pub/scm/linux/kernel/git/tmlind/linux-omap.git omap-for-v5.7/dss-probe
[1] https://git.kernel.org/pub/scm/linux/kernel/git/tmlind/linux-omap.git/commit/?h=omap-for-v5.7/dss-probe&id=cef766300353613aa273791f70b3125d1f0420ae
diff mbox series

Patch

diff --git a/drivers/gpu/drm/omapdrm/dss/dss.c b/drivers/gpu/drm/omapdrm/dss/dss.c
--- a/drivers/gpu/drm/omapdrm/dss/dss.c
+++ b/drivers/gpu/drm/omapdrm/dss/dss.c
@@ -1339,9 +1339,15 @@  static int dss_component_compare(struct device *dev, void *data)
 	return dev == child;
 }
 
+struct dss_component_match_data {
+	struct device *dev;
+	struct component_match **match;
+};
+
 static int dss_add_child_component(struct device *dev, void *data)
 {
-	struct component_match **match = data;
+	struct dss_component_match_data *cmatch = data;
+	struct component_match **match = cmatch->match;
 
 	/*
 	 * HACK
@@ -1352,7 +1358,17 @@  static int dss_add_child_component(struct device *dev, void *data)
 	if (strstr(dev_name(dev), "rfbi"))
 		return 0;
 
-	component_match_add(dev->parent, match, dss_component_compare, dev);
+	/*
+	 * Handle possible interconnect target modules defined within the DSS.
+	 * The DSS components can be children of an interconnect target module
+	 * after the device tree has been updated for the module data.
+	 * See also omapdss_boot_init() for compatible fixup.
+	 */
+	if (strstr(dev_name(dev), "target-module"))
+		return device_for_each_child(dev, cmatch,
+					     dss_add_child_component);
+
+	component_match_add(cmatch->dev, match, dss_component_compare, dev);
 
 	return 0;
 }
@@ -1395,6 +1411,7 @@  static int dss_probe_hardware(struct dss_device *dss)
 static int dss_probe(struct platform_device *pdev)
 {
 	const struct soc_device_attribute *soc;
+	struct dss_component_match_data cmatch;
 	struct component_match *match = NULL;
 	struct resource *dss_mem;
 	struct dss_device *dss;
@@ -1472,7 +1489,9 @@  static int dss_probe(struct platform_device *pdev)
 
 	omapdss_gather_components(&pdev->dev);
 
-	device_for_each_child(&pdev->dev, &match, dss_add_child_component);
+	cmatch.dev = &pdev->dev;
+	cmatch.match = &match;
+	device_for_each_child(&pdev->dev, &cmatch, dss_add_child_component);
 
 	r = component_master_add_with_match(&pdev->dev, &dss_component_ops, match);
 	if (r)
diff --git a/drivers/gpu/drm/omapdrm/dss/omapdss-boot-init.c b/drivers/gpu/drm/omapdrm/dss/omapdss-boot-init.c
--- a/drivers/gpu/drm/omapdrm/dss/omapdss-boot-init.c
+++ b/drivers/gpu/drm/omapdrm/dss/omapdss-boot-init.c
@@ -183,9 +183,24 @@  static const struct of_device_id omapdss_of_fixups_whitelist[] __initconst = {
 	{},
 };
 
+static void __init omapdss_find_children(struct device_node *np)
+{
+	struct device_node *child;
+
+	for_each_available_child_of_node(np, child) {
+		if (!of_find_property(child, "compatible", NULL))
+			continue;
+
+		omapdss_walk_device(child, true);
+
+		if (of_device_is_compatible(child, "ti,sysc"))
+			omapdss_find_children(child);
+	}
+}
+
 static int __init omapdss_boot_init(void)
 {
-	struct device_node *dss, *child;
+	struct device_node *dss;
 
 	INIT_LIST_HEAD(&dss_conv_list);
 
@@ -195,13 +210,7 @@  static int __init omapdss_boot_init(void)
 		return 0;
 
 	omapdss_walk_device(dss, true);
-
-	for_each_available_child_of_node(dss, child) {
-		if (!of_find_property(child, "compatible", NULL))
-			continue;
-
-		omapdss_walk_device(child, true);
-	}
+	omapdss_find_children(dss);
 
 	while (!list_empty(&dss_conv_list)) {
 		struct dss_conv_node *n;