staging: allow omap4iss to be modular

The OMAP4 camera support depends on I2C and VIDEO_V4L2, both of which can be loadable modules. This causes build failures if we want the camera driver to be built-in.

This can be solved by turning the option into "tristate", which unfortunately causes another problem, because the driver incorrectly calls a platform-internal interface for omap4_ctrl_pad_readl/omap4_ctrl_pad_writel. To work around that, we can export those symbols, but that isn't really the correct solution, as we should not have dependencies on platform code this way.

Signed-off-by Arnd Bergmann <[email protected]>

---
This is one of just two patches we currently need to get 'make allmodconfig' to build again on ARM.

arch/arm/mach-omap2/control.c +2 -0

index 751f354..05d2d98 100644
@@ -190,11 +190,13 @@ u32 omap4_ctrl_pad_readl(u16 offset)
 {
 	return readl_relaxed(OMAP4_CTRL_PAD_REGADDR(offset));
 }
+EXPORT_SYMBOL_GPL(omap4_ctrl_pad_readl);
 
 void omap4_ctrl_pad_writel(u32 val, u16 offset)
 {
 	writel_relaxed(val, OMAP4_CTRL_PAD_REGADDR(offset));
 }
+EXPORT_SYMBOL_GPL(omap4_ctrl_pad_writel);
 
 #ifdef CONFIG_ARCH_OMAP3
 

drivers/staging/media/omap4iss/Kconfig +1 -2

index 78b0fba..0c3e3c1 100644
@@ -1,5 +1,5 @@
 config VIDEO_OMAP4
-	bool "OMAP 4 Camera support"
+	tristate "OMAP 4 Camera support"
 	depends on VIDEO_V4L2 && VIDEO_V4L2_SUBDEV_API && I2C && ARCH_OMAP4
 	select VIDEOBUF2_DMA_CONTIG
 	---help---
 
--

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Quoted 44 lines · Arnd Bergmann

The OMAP4 camera support depends on I2C and VIDEO_V4L2, both of which can be loadable modules. This causes build failures if we want the camera driver to be built-in.

This can be solved by turning the option into "tristate", which unfortunately causes another problem, because the driver incorrectly calls a platform-internal interface for omap4_ctrl_pad_readl/omap4_ctrl_pad_writel. To work around that, we can export those symbols, but that isn't really the correct solution, as we should not have dependencies on platform code this way.

Signed-off-by Arnd Bergmann <[email protected]>

---
This is one of just two patches we currently need to get 'make allmodconfig' to build again on ARM.

arch/arm/mach-omap2/control.c +2 -0

index 751f354..05d2d98 100644
@@ -190,11 +190,13 @@ u32 omap4_ctrl_pad_readl(u16 offset)
 {
 	return readl_relaxed(OMAP4_CTRL_PAD_REGADDR(offset));
 }
+EXPORT_SYMBOL_GPL(omap4_ctrl_pad_readl);
 
 void omap4_ctrl_pad_writel(u32 val, u16 offset)
 {
 	writel_relaxed(val, OMAP4_CTRL_PAD_REGADDR(offset));
 }
+EXPORT_SYMBOL_GPL(omap4_ctrl_pad_writel);
 
 #ifdef CONFIG_ARCH_OMAP3
 

drivers/staging/media/omap4iss/Kconfig +1 -1

index 78b0fba..0c3e3c1 100644
@@ -1,5 +1,5 @@
 config VIDEO_OMAP4
-	bool "OMAP 4 Camera support"
+	tristate "OMAP 4 Camera support"
 	depends on VIDEO_V4L2 && VIDEO_V4L2_SUBDEV_API && I2C && ARCH_OMAP4

drivers/staging/media/omap4iss/Kconfig line 5

Quoted 3 lines

drivers/staging/media/omap4iss/Kconfig +0 -0

 	select VIDEOBUF2_DMA_CONTIG
 	---help---

This was discussed in detail here:
http://marc.info/?t=140198692500001&r=1&w=2
Direct dependency from a staging driver to mach-omap2 driver is not something we'd like, right?

From 3a965f4fd5a6b3ef4a66aa4e7c916cfd34fd5706 Mon Sep 17 00:00:00 2001

Quoted 45 lines · On Wednesday 11 June 2014 09:42:04 Nishanth Menon wrote:

Quoted 44 lines · Arnd Bergmann

The OMAP4 camera support depends on I2C and VIDEO_V4L2, both of which can be loadable modules. This causes build failures if we want the camera driver to be built-in.

This can be solved by turning the option into "tristate", which unfortunately causes another problem, because the driver incorrectly calls a platform-internal interface for omap4_ctrl_pad_readl/omap4_ctrl_pad_writel. To work around that, we can export those symbols, but that isn't really the correct solution, as we should not have dependencies on platform code this way.

Signed-off-by Arnd Bergmann <[email protected]>

---
This is one of just two patches we currently need to get 'make allmodconfig' to build again on ARM.

arch/arm/mach-omap2/control.c +2 -0

index 751f354..05d2d98 100644
@@ -190,11 +190,13 @@ u32 omap4_ctrl_pad_readl(u16 offset)
 {
 	return readl_relaxed(OMAP4_CTRL_PAD_REGADDR(offset));
 }
+EXPORT_SYMBOL_GPL(omap4_ctrl_pad_readl);
 
 void omap4_ctrl_pad_writel(u32 val, u16 offset)
 {
 	writel_relaxed(val, OMAP4_CTRL_PAD_REGADDR(offset));
 }
+EXPORT_SYMBOL_GPL(omap4_ctrl_pad_writel);
 
 #ifdef CONFIG_ARCH_OMAP3
 

drivers/staging/media/omap4iss/Kconfig +1 -1

index 78b0fba..0c3e3c1 100644
@@ -1,5 +1,5 @@
 config VIDEO_OMAP4
-	bool "OMAP 4 Camera support"
+	tristate "OMAP 4 Camera support"
 	depends on VIDEO_V4L2 && VIDEO_V4L2_SUBDEV_API && I2C && ARCH_OMAP4

Quoted 8 lines

drivers/staging/media/omap4iss/Kconfig line 5

Quoted 3 lines

drivers/staging/media/omap4iss/Kconfig +0 -0

 	select VIDEOBUF2_DMA_CONTIG
 	---help---

This was discussed in detail here:
http://marc.info/?t=140198692500001&r=1&w=2
Direct dependency from a staging driver to mach-omap2 driver is not something we'd like, right?

So it was decided to just leave ARM allmodconfig broken?

Why not at least do this instead?

8<----
From 3a965f4fd5a6b3ef4a66aa4e7c916cfd34fd5706 Mon Sep 17 00:00:00 2001
From: Arnd Bergmann <[email protected]>
Date: Tue, 21 Jan 2014 09:32:43 +0100
Subject: [PATCH] [media] staging: tighten omap4iss dependencies

The OMAP4 camera support depends on I2C and VIDEO_V4L2, both of which can be loadable modules. This causes build failures if we want the camera driver to be built-in.

This can be solved by turning the option into "tristate", which unfortunately causes another problem, because the driver incorrectly calls a platform-internal interface for omap4_ctrl_pad_readl/omap4_ctrl_pad_writel.

Instead, this patch just forbids the invalid configurations and ensures that the driver can only be built if all its dependencies are built-in.

Signed-off-by Arnd Bergmann <[email protected]>

drivers/staging/media/omap4iss/Kconfig +0 -0

index 78b0fba..8afc6fe 100644

Quoted 45 lines · On Wednesday 11 June 2014 09:42:04 Nishanth Menon wrote:

Quoted 44 lines · Arnd Bergmann

The OMAP4 camera support depends on I2C and VIDEO_V4L2, both of which can be loadable modules. This causes build failures if we want the camera driver to be built-in.

This can be solved by turning the option into "tristate", which unfortunately causes another problem, because the driver incorrectly calls a platform-internal interface for omap4_ctrl_pad_readl/omap4_ctrl_pad_writel. To work around that, we can export those symbols, but that isn't really the correct solution, as we should not have dependencies on platform code this way.

Signed-off-by Arnd Bergmann <[email protected]>

---
This is one of just two patches we currently need to get 'make allmodconfig' to build again on ARM.

arch/arm/mach-omap2/control.c +2 -0

index 751f354..05d2d98 100644
@@ -190,11 +190,13 @@ u32 omap4_ctrl_pad_readl(u16 offset)
 {
 	return readl_relaxed(OMAP4_CTRL_PAD_REGADDR(offset));
 }
+EXPORT_SYMBOL_GPL(omap4_ctrl_pad_readl);
 
 void omap4_ctrl_pad_writel(u32 val, u16 offset)
 {
 	writel_relaxed(val, OMAP4_CTRL_PAD_REGADDR(offset));
 }
+EXPORT_SYMBOL_GPL(omap4_ctrl_pad_writel);
 
 #ifdef CONFIG_ARCH_OMAP3
 

drivers/staging/media/omap4iss/Kconfig +1 -1

index 78b0fba..0c3e3c1 100644
@@ -1,5 +1,5 @@
 config VIDEO_OMAP4
-	bool "OMAP 4 Camera support"
+	tristate "OMAP 4 Camera support"
 	depends on VIDEO_V4L2 && VIDEO_V4L2_SUBDEV_API && I2C && ARCH_OMAP4

Quoted 8 lines

drivers/staging/media/omap4iss/Kconfig line 5

Quoted 3 lines

drivers/staging/media/omap4iss/Kconfig +0 -0

 	select VIDEOBUF2_DMA_CONTIG
 	---help---

This was discussed in detail here:
http://marc.info/?t=140198692500001&r=1&w=2
Direct dependency from a staging driver to mach-omap2 driver is not something we'd like, right?

So it was decided to just leave ARM allmodconfig broken?

Why not at least do this instead?

8<----
From 3a965f4fd5a6b3ef4a66aa4e7c916cfd34fd5706 Mon Sep 17 00:00:00 2001
From: Arnd Bergmann <[email protected]>
Date: Tue, 21 Jan 2014 09:32:43 +0100
Subject: [PATCH] [media] staging: tighten omap4iss dependencies

The OMAP4 camera support depends on I2C and VIDEO_V4L2, both of which can be loadable modules. This causes build failures if we want the camera driver to be built-in.

This can be solved by turning the option into "tristate", which unfortunately causes another problem, because the driver incorrectly calls a platform-internal interface for omap4_ctrl_pad_readl/omap4_ctrl_pad_writel.

Instead, this patch just forbids the invalid configurations and ensures that the driver can only be built if all its dependencies are built-in.

Signed-off-by Arnd Bergmann <[email protected]>

drivers/staging/media/omap4iss/Kconfig +1 -1

index 78b0fba..8afc6fe 100644
@@ -1,6 +1,6 @@
 config VIDEO_OMAP4
 	bool "OMAP 4 Camera support"
-	depends on VIDEO_V4L2 && VIDEO_V4L2_SUBDEV_API && I2C && ARCH_OMAP4
+	depends on VIDEO_V4L2=y && VIDEO_V4L2_SUBDEV_API && I2C=y && ARCH_OMAP4
 	select VIDEOBUF2_DMA_CONTIG
 	---help---
 	  Driver for an OMAP 4 ISS controller.

Quoted 37 lines · On Wednesday 11 June 2014 09:42:04 Nishanth Menon wrote:

Quoted 36 lines · Arnd Bergmann

The OMAP4 camera support depends on I2C and VIDEO_V4L2, both of which can be loadable modules. This causes build failures if we want the camera driver to be built-in.

This can be solved by turning the option into "tristate", which unfortunately causes another problem, because the driver incorrectly calls a platform-internal interface for omap4_ctrl_pad_readl/omap4_ctrl_pad_writel. To work around that, we can export those symbols, but that isn't really the correct solution, as we should not have dependencies on platform code this way.

Signed-off-by Arnd Bergmann <[email protected]>

---
This is one of just two patches we currently need to get 'make allmodconfig' to build again on ARM.

arch/arm/mach-omap2/control.c +2 -0

index 751f354..05d2d98 100644
@@ -190,11 +190,13 @@ u32 omap4_ctrl_pad_readl(u16 offset)
 {
 	return readl_relaxed(OMAP4_CTRL_PAD_REGADDR(offset));
 }
+EXPORT_SYMBOL_GPL(omap4_ctrl_pad_readl);
 
 void omap4_ctrl_pad_writel(u32 val, u16 offset)
 {
 	writel_relaxed(val, OMAP4_CTRL_PAD_REGADDR(offset));
 }
+EXPORT_SYMBOL_GPL(omap4_ctrl_pad_writel);
 
 #ifdef CONFIG_ARCH_OMAP3
 

Quoted 16 lines

drivers/staging/media/omap4iss/Kconfig line 5

Quoted 11 lines

(quoted diff) +0 -0

b/drivers/staging/media/omap4iss/Kconfig index 78b0fba..0c3e3c1 100644

drivers/staging/media/omap4iss/Kconfig +1 -1

@@ -1,5 +1,5 @@
 config VIDEO_OMAP4
-	bool "OMAP 4 Camera support"
+	tristate "OMAP 4 Camera support"
 	depends on VIDEO_V4L2 && VIDEO_V4L2_SUBDEV_API && I2C && ARCH_OMAP4
 	select VIDEOBUF2_DMA_CONTIG
 	---help---

This was discussed in detail here:
http://marc.info/?t=140198692500001&r=1&w=2
Direct dependency from a staging driver to mach-omap2 driver is not something we'd like, right?

So it was decided to just leave ARM allmodconfig broken?

Why not at least do this instead?

8<----
From 3a965f4fd5a6b3ef4a66aa4e7c916cfd34fd5706 Mon Sep 17 00:00:00 2001
From: Arnd Bergmann <[email protected]>
Date: Tue, 21 Jan 2014 09:32:43 +0100
Subject: [PATCH] [media] staging: tighten omap4iss dependencies

The OMAP4 camera support depends on I2C and VIDEO_V4L2, both of which can be loadable modules. This causes build failures if we want the camera driver to be built-in.

This can be solved by turning the option into "tristate", which unfortunately causes another problem, because the driver incorrectly calls a platform-internal interface for omap4_ctrl_pad_readl/omap4_ctrl_pad_writel.

Instead, this patch just forbids the invalid configurations and ensures that the driver can only be built if all its dependencies are built-in.

Signed-off-by Arnd Bergmann <[email protected]>

(quoted diff) +0 -0

b/drivers/staging/media/omap4iss/Kconfig index 78b0fba..8afc6fe 100644

drivers/staging/media/omap4iss/Kconfig +1 -1

@@ -1,6 +1,6 @@
 config VIDEO_OMAP4
 	bool "OMAP 4 Camera support"
-	depends on VIDEO_V4L2 && VIDEO_V4L2_SUBDEV_API && I2C && ARCH_OMAP4
+	depends on VIDEO_V4L2=y && VIDEO_V4L2_SUBDEV_API && I2C=y && ARCH_OMAP4
 	select VIDEOBUF2_DMA_CONTIG
 	---help---
 	  Driver for an OMAP 4 ISS controller.

Quoted 18 lines

From 3a965f4fd5a6b3ef4a66aa4e7c916cfd34fd5706 Mon Sep 17 00:00:00 2001
From: Arnd Bergmann <[email protected]>
Date: Tue, 21 Jan 2014 09:32:43 +0100
Subject: [PATCH] [media] staging: tighten omap4iss dependencies

The OMAP4 camera support depends on I2C and VIDEO_V4L2, both of which can be loadable modules. This causes build failures if we want the camera driver to be built-in.

This can be solved by turning the option into "tristate", which unfortunately causes another problem, because the driver incorrectly calls a platform-internal interface for omap4_ctrl_pad_readl/omap4_ctrl_pad_writel.

Instead, this patch just forbids the invalid configurations and ensures that the driver can only be built if all its dependencies are built-in.

Quoted 1 line

Signed-off-by Arnd Bergmann <[email protected]>

Acked-by Laurent Pinchart <[email protected]>

Should I take this in my tree for v3.17 or would you like to fast-track it ?

Quoted 18 lines · On Thursday 12 June 2014 16:12:17 Laurent Pinchart wrote:

Quoted 18 lines

From 3a965f4fd5a6b3ef4a66aa4e7c916cfd34fd5706 Mon Sep 17 00:00:00 2001
From: Arnd Bergmann <[email protected]>
Date: Tue, 21 Jan 2014 09:32:43 +0100
Subject: [PATCH] [media] staging: tighten omap4iss dependencies

The OMAP4 camera support depends on I2C and VIDEO_V4L2, both of which can be loadable modules. This causes build failures if we want the camera driver to be built-in.

This can be solved by turning the option into "tristate", which unfortunately causes another problem, because the driver incorrectly calls a platform-internal interface for omap4_ctrl_pad_readl/omap4_ctrl_pad_writel.

Instead, this patch just forbids the invalid configurations and ensures that the driver can only be built if all its dependencies are built-in.

Quoted 6 lines

Quoted 1 line

Signed-off-by Arnd Bergmann <[email protected]>

Acked-by Laurent Pinchart <[email protected]>

Should I take this in my tree for v3.17 or would you like to fast-track it ?

I'd actually like to see it in 3.15 as a stable backport if possible,

but definitely in 3.16. What is the normal path for staging/media but fix patches?

Quoted 21 lines · Arnd Bergmann

Quoted 20 lines · On Thursday 12 June 2014 16:12:17 Laurent Pinchart wrote:

Quoted 19 lines

From 3a965f4fd5a6b3ef4a66aa4e7c916cfd34fd5706 Mon Sep 17 00:00:00 2001
From: Arnd Bergmann <[email protected]>
Date: Tue, 21 Jan 2014 09:32:43 +0100
Subject: [PATCH] [media] staging: tighten omap4iss dependencies

The OMAP4 camera support depends on I2C and VIDEO_V4L2, both of which can be loadable modules. This causes build failures if we want the camera driver to be built-in.

This can be solved by turning the option into "tristate", which unfortunately causes another problem, because the driver incorrectly calls a platform-internal interface for omap4_ctrl_pad_readl/omap4_ctrl_pad_writel.

Instead, this patch just forbids the invalid configurations and ensures that the driver can only be built if all its dependencies are built-in.

Signed-off-by Arnd Bergmann <[email protected]>

Quoted 6 lines

Quoted 4 lines

Acked-by Laurent Pinchart <[email protected]>

Should I take this in my tree for v3.17 or would you like to fast-track it ?

I'd actually like to see it in 3.15 as a stable backport if possible,

It's not stable material, sorry.

Quoted 2 lines

but definitely in 3.16. What is the normal path for staging/media but fix patches?

Through Mauro's tree.

Quoted 23 lines · On Thursday 12 June 2014 07:25:15 Greg KH wrote:

Quoted 22 lines · Arnd Bergmann

Quoted 21 lines · On Thursday 12 June 2014 16:12:17 Laurent Pinchart wrote:

Quoted 20 lines

From 3a965f4fd5a6b3ef4a66aa4e7c916cfd34fd5706 Mon Sep 17 00:00:00 2001
From: Arnd Bergmann <[email protected]>
Date: Tue, 21 Jan 2014 09:32:43 +0100
Subject: [PATCH] [media] staging: tighten omap4iss dependencies

The OMAP4 camera support depends on I2C and VIDEO_V4L2, both of which can be loadable modules. This causes build failures if we want the camera driver to be built-in.

This can be solved by turning the option into "tristate", which unfortunately causes another problem, because the driver incorrectly calls a platform-internal interface for omap4_ctrl_pad_readl/omap4_ctrl_pad_writel.

Instead, this patch just forbids the invalid configurations and ensures that the driver can only be built if all its dependencies are built-in.

Signed-off-by Arnd Bergmann <[email protected]>

Quoted 7 lines

Quoted 5 lines

Quoted 4 lines

Acked-by Laurent Pinchart <[email protected]>

Should I take this in my tree for v3.17 or would you like to fast-track it ?> >

I'd actually like to see it in 3.15 as a stable backport if possible,

It's not stable material, sorry.

To clarify, I was talking about second version of the patch, not the original one. It just does this:

Quoted 8 lines

config VIDEO_OMAP4
bool "OMAP 4 Camera support"

(quoted diff) +1 -1

-     depends on VIDEO_V4L2 && VIDEO_V4L2_SUBDEV_API && I2C && ARCH_OMAP4
+     depends on VIDEO_V4L2=y && VIDEO_V4L2_SUBDEV_API && I2C=y &&

ARCH_OMAP4
select VIDEOBUF2_DMA_CONTIG
---help---
Driver for an OMAP 4 ISS controller.

which enforces that configurations that cannot be compiled will not be selectable in Kconfig, so we can have allmodconfig working. I thought that was ok for -stable.

Quoted 4 lines

Quoted 2 lines

but definitely in 3.16. What is the normal path for staging/media but fix patches?

Through Mauro's tree.

Ok.

Quoted 22 lines · On Thursday 12 June 2014 07:25:15 Greg KH wrote:

Quoted 21 lines · Arnd Bergmann

Quoted 20 lines · On Thursday 12 June 2014 16:12:17 Laurent Pinchart wrote:

Quoted 19 lines

From 3a965f4fd5a6b3ef4a66aa4e7c916cfd34fd5706 Mon Sep 17 00:00:00 2001
From: Arnd Bergmann <[email protected]>
Date: Tue, 21 Jan 2014 09:32:43 +0100
Subject: [PATCH] [media] staging: tighten omap4iss dependencies

The OMAP4 camera support depends on I2C and VIDEO_V4L2, both of which can be loadable modules. This causes build failures if we want the camera driver to be built-in.

This can be solved by turning the option into "tristate", which unfortunately causes another problem, because the driver incorrectly calls a platform-internal interface for omap4_ctrl_pad_readl/omap4_ctrl_pad_writel.

Instead, this patch just forbids the invalid configurations and ensures that the driver can only be built if all its dependencies are built-in.

Signed-off-by Arnd Bergmann <[email protected]>

Quoted 8 lines

Quoted 6 lines

Quoted 4 lines

Acked-by Laurent Pinchart <[email protected]>

Should I take this in my tree for v3.17 or would you like to fast-track it ?

I'd actually like to see it in 3.15 as a stable backport if possible,

It's not stable material, sorry.

To clarify, I was talking about second version of the patch, not the original one. It just does this:

drivers/staging/media/omap4iss/Kconfig line 6

Quoted 7 lines

config VIDEO_OMAP4
bool "OMAP 4 Camera support"

drivers/staging/media/omap4iss/Kconfig +1 -1

-     depends on VIDEO_V4L2 && VIDEO_V4L2_SUBDEV_API && I2C && ARCH_OMAP4
+     depends on VIDEO_V4L2=y && VIDEO_V4L2_SUBDEV_API && I2C=y && ARCH_OMAP4
      select VIDEOBUF2_DMA_CONTIG
      ---help---
        Driver for an OMAP 4 ISS controller.

which enforces that configurations that cannot be compiled will not be selectable in Kconfig, so we can have allmodconfig working. I thought that was ok for -stable.

The OMAP4 camera support depends on I2C and VIDEO_V4L2, both of which can be loadable modules. This causes build failures if we want the camera driver to be built-in.

This can be solved by turning the option into "tristate", which unfortunately causes another problem, because the driver incorrectly calls a platform-internal interface for omap4_ctrl_pad_readl/omap4_ctrl_pad_writel. To work around that, we can export those symbols, but that isn't really the correct solution, as we should not have dependencies on platform code this way.

Signed-off-by Arnd Bergmann <[email protected]>

---
This is one of just two patches we currently need to get 'make allmodconfig' to build again on ARM.

arch/arm/mach-omap2/control.c +0 -0

index 751f354..05d2d98 100644
@@ -190,11 +190,13 @@ u32 omap4_ctrl_pad_readl(u16 offset)
 {
 	return readl_relaxed(OMAP4_CTRL_PAD_REGADDR(offset));

Quoted 3 lines · Arnd Bergmann

The OMAP4 camera support depends on I2C and VIDEO_V4L2, both of which can be loadable modules. This causes build failures if we want the camera driver to be built-in.

That's good news, but let's not fix it this way.

Quoted 20 lines

This can be solved by turning the option into "tristate", which unfortunately causes another problem, because the driver incorrectly calls a platform-internal interface for omap4_ctrl_pad_readl/omap4_ctrl_pad_writel. To work around that, we can export those symbols, but that isn't really the correct solution, as we should not have dependencies on platform code this way.

Signed-off-by Arnd Bergmann <[email protected]>

---
This is one of just two patches we currently need to get 'make allmodconfig' to build again on ARM.

arch/arm/mach-omap2/control.c +0 -0

index 751f354..05d2d98 100644
@@ -190,11 +190,13 @@ u32 omap4_ctrl_pad_readl(u16 offset)
 {
 	return readl_relaxed(OMAP4_CTRL_PAD_REGADDR(offset));

arch/arm/mach-omap2/control.c u32 omap4_ctrl_pad_readl(u16 offset) · line 201

Quoted 10 lines

arch/arm/mach-omap2/control.c +2 -0

 }
+EXPORT_SYMBOL_GPL(omap4_ctrl_pad_readl);
 
 void omap4_ctrl_pad_writel(u32 val, u16 offset)
 {
 	writel_relaxed(val, OMAP4_CTRL_PAD_REGADDR(offset));
 }
+EXPORT_SYMBOL_GPL(omap4_ctrl_pad_writel);
 
 #ifdef CONFIG_ARCH_OMAP3

Exporting these will likely cause immediate misuse in other drivers all over the place.

These should just use either pinctrl-single.c instead for muxing. Or if they are not mux registers, we do have the syscon mapping available in omap4.dtsi that pbias-regulator.c is already using.

Laurent, got any better ideas?

Quoted 6 lines · On Wednesday 11 June 2014 07:47:54 Tony Lindgren wrote:

These should just use either pinctrl-single.c instead for muxing. Or if they are not mux registers, we do have the syscon mapping available in omap4.dtsi that pbias-regulator.c is already using.

Laurent, got any better ideas?

The ISS driver needs to write a single register, which contains several independent fields. They thus need to be controlled by a single driver. Some of them might be considered to be related to pinmuxing (although I disagree on that), others are certainly not about muxing (there are clock gate bits for instance).

Using the syscon mapping seems like the best option. I'll give it a try.

Quoted 7 lines · Laurent Pinchart

Quoted 5 lines · On Wednesday 11 June 2014 07:47:54 Tony Lindgren wrote:

These should just use either pinctrl-single.c instead for muxing. Or if they are not mux registers, we do have the syscon mapping available in omap4.dtsi that pbias-regulator.c is already using.

Laurent, got any better ideas?

Quoted 7 lines

The ISS driver needs to write a single register, which contains several independent fields. They thus need to be controlled by a single driver. Some of them might be considered to be related to pinmuxing (although I disagree on that), others are certainly not about muxing (there are clock gate bits for instance).

Using the syscon mapping seems like the best option. I'll give it a try.

OK if it's not strictly pinctrl related then let's not use pinctrl-single,bits for it. You may be able to implement one or more framework drivers for it for pinctrl/regulator/clock/transceiver whatever that register is doing.

In any case it's best to have that handling in a separate helper driver somewhere as it's a separate piece of hardware from the camera module. If it does not fit into any existing frameworks then it's best to have it in a separate driver with the camera driver.

Hi Tony,

Quoted 21 lines · On Thursday 12 June 2014 08:15:35 Tony Lindgren wrote:

Quoted 7 lines · Laurent Pinchart

Quoted 5 lines · On Wednesday 11 June 2014 07:47:54 Tony Lindgren wrote:

These should just use either pinctrl-single.c instead for muxing. Or if they are not mux registers, we do have the syscon mapping available in omap4.dtsi that pbias-regulator.c is already using.

Laurent, got any better ideas?

Quoted 7 lines

The ISS driver needs to write a single register, which contains several independent fields. They thus need to be controlled by a single driver. Some of them might be considered to be related to pinmuxing (although I disagree on that), others are certainly not about muxing (there are clock gate bits for instance).

Using the syscon mapping seems like the best option. I'll give it a try.

OK if it's not strictly pinctrl related then let's not use pinctrl-single,bits for it. You may be able to implement one or more framework drivers for it for pinctrl/regulator/clock/transceiver whatever that register is doing.

Quoted 4 lines

In any case it's best to have that handling in a separate helper driver somewhere as it's a separate piece of hardware from the camera module. If it does not fit into any existing frameworks then it's best to have it in a separate driver with the camera driver.

The register contains the following fields that control the two CSI2 PHYs (PHY1 and PHY2).

31    CAMERARX_CSI22_LANEENABLE2   PHY2 Lane 2 (CSI22_DX2, CSI22_DY2) Enable
30    CAMERARX_CSI22_LANEENABLE1   PHY2 Lane 1 (CSI22_DX1, CSI22_DY1) Enable
29    CAMERARX_CSI22_LANEENABLE0   PHY2 Lane 0 (CSI22_DX0, CSI22_DY0) Enable
28    CAMERARX_CSI21_LANEENABLE4   PHY1 Lane 4 (CSI21_DX4, CSI21_DY4) Enable
27    CAMERARX_CSI21_LANEENABLE3   PHY1 Lane 3 (CSI21_DX3, CSI21_DY3) Enable
26    CAMERARX_CSI21_LANEENABLE2   PHY1 Lane 2 (CSI21_DX2, CSI21_DY2) Enable
25    CAMERARX_CSI21_LANEENABLE1   PHY1 Lane 1 (CSI21_DX1, CSI21_DY1) Enable
24    CAMERARX_CSI21_LANEENABLE0   PHY1 Lane 0 (CSI21_DX0, CSI21_DY0) Enable
21    CAMERARX_CSI22_CTRLCLKEN     PHY2 Clock Enable
20:19 CAMERARX_CSI22_CAMMODE       PHY2 Mode (CCP2, CSI1, CSI2)
18    CAMERARX_CSI21_CTRLCLKEN     PHY1 Clock Enable
17:16 CAMERARX_CSI21_CAMMODE       PHY1 Mode (CCP2, CSI1, CSI2)

Bits 18 and 21 could be exposed through CCF. Bits 24 to 31 enable/disable the CSI2 lanes, so it could be argued that they could be exposed through the pinctrl framework. However, they need to be configured independently, possibly at runtime. I'm thus not sure pinctrl would be a good idea. Bits 17:16 and 20:19 don't fit in existing frameworks.

Given that this register is specific to the ISS, I think handling it as a separate device through a separate driver would only complicate the implementation without any real benefit.

Quoted 52 lines · Laurent Pinchart

Quoted 22 lines · On Thursday 12 June 2014 08:15:35 Tony Lindgren wrote:

Quoted 7 lines · Laurent Pinchart

Quoted 5 lines · On Wednesday 11 June 2014 07:47:54 Tony Lindgren wrote:

These should just use either pinctrl-single.c instead for muxing. Or if they are not mux registers, we do have the syscon mapping available in omap4.dtsi that pbias-regulator.c is already using.

Laurent, got any better ideas?

Quoted 8 lines

The ISS driver needs to write a single register, which contains several independent fields. They thus need to be controlled by a single driver. Some of them might be considered to be related to pinmuxing (although I disagree on that), others are certainly not about muxing (there are clock gate bits for instance).

Using the syscon mapping seems like the best option. I'll give it a try.

OK if it's not strictly pinctrl related then let's not use pinctrl-single,bits for it. You may be able to implement one or more framework drivers for it for pinctrl/regulator/clock/transceiver whatever that register is doing.

Quoted 4 lines

In any case it's best to have that handling in a separate helper driver somewhere as it's a separate piece of hardware from the camera module. If it does not fit into any existing frameworks then it's best to have it in a separate driver with the camera driver.

The register contains the following fields that control the two CSI2 PHYs (PHY1 and PHY2).

31 CAMERARX_CSI22_LANEENABLE2 PHY2 Lane 2 (CSI22_DX2, CSI22_DY2)
Enable
30 CAMERARX_CSI22_LANEENABLE1 PHY2 Lane 1 (CSI22_DX1, CSI22_DY1)
Enable
29 CAMERARX_CSI22_LANEENABLE0 PHY2 Lane 0 (CSI22_DX0, CSI22_DY0)
Enable
28 CAMERARX_CSI21_LANEENABLE4 PHY1 Lane 4 (CSI21_DX4, CSI21_DY4)
Enable
27 CAMERARX_CSI21_LANEENABLE3 PHY1 Lane 3 (CSI21_DX3, CSI21_DY3)
Enable
26 CAMERARX_CSI21_LANEENABLE2 PHY1 Lane 2 (CSI21_DX2, CSI21_DY2)
Enable
25 CAMERARX_CSI21_LANEENABLE1 PHY1 Lane 1 (CSI21_DX1, CSI21_DY1)
Enable
24 CAMERARX_CSI21_LANEENABLE0 PHY1 Lane 0 (CSI21_DX0, CSI21_DY0)
Enable

21    CAMERARX_CSI22_CTRLCLKEN     PHY2 Clock Enable
20:19 CAMERARX_CSI22_CAMMODE       PHY2 Mode (CCP2, CSI1, CSI2)
18    CAMERARX_CSI21_CTRLCLKEN     PHY1 Clock Enable
17:16 CAMERARX_CSI21_CAMMODE       PHY1 Mode (CCP2, CSI1, CSI2)

Quoted 5 lines

Bits 18 and 21 could be exposed through CCF. Bits 24 to 31 enable/disable the CSI2 lanes, so it could be argued that they could be exposed through the pinctrl framework. However, they need to be configured independently, possibly at runtime. I'm thus not sure pinctrl would be a good idea. Bits 17:16 and 20:19 don't fit in existing frameworks.

OK thanks for the info. Sounds like drivers/phy might be the right location for it then and then the phy driver can use the syscon regmap.

Quoted 3 lines

Given that this register is specific to the ISS, I think handling it as a separate device through a separate driver would only complicate the implementation without any real benefit.

Even though it's one register, it shoud still be treated separately from the camera driver. The problems with keeping the register access to the control module in the camera driver are at least following:

1. They live in separate hardware modules that can be clocked separately

2. Doing a read-back to flush a posted write in one hardware module most likely won't flush the write to other and that can lead into hard to find mysterious bugs

3. If we ever have a common system control module driver, we need to rewrite all the system control module register tinkering in the drivers

So it's best to try to use an existing framework for it. That avoids tons of pain later on ;)

Quoted 2 lines · On Thursday 12 June 2014 22:30:44 Tony Lindgren wrote:

1. They live in separate hardware modules that can be clocked separately

Actually I don't think that's true. The CSI2 PHY is part of the camera device, with all its registers but the one above in the camera device register space. For some weird reason a couple of bits were pushed to the control module, but that doesn't make the CSI2 PHY itself a separate device.

Quoted 3 lines

2. Doing a read-back to flush a posted write in one hardware module most likely won't flush the write to other and that can lead into hard to find mysterious bugs

The OMAP4 ISS driver can just read back the CAMERA_RX register, can't it ?

Quoted 2 lines

3. If we ever have a common system control module driver, we need to rewrite all the system control module register tinkering in the drivers

Sure, but that's already the case today, as the OMAP4 ISS driver already accesses the control module register directly. I won't make that worse :-)

Quoted 2 lines

So it's best to try to use an existing framework for it. That avoids tons of pain later on ;)

I agree, but I don't think the PHY framework would be the right abstraction. As explained above the CSI2 PHY is part of the OMAP4 ISS, so modeling its single control module register as a PHY would be a hack.

Quoted 8 lines · Laurent Pinchart

Quoted 1 line · On Thursday 12 June 2014 22:30:44 Tony Lindgren wrote:

1. They live in separate hardware modules that can be clocked separately

Actually I don't think that's true. The CSI2 PHY is part of the camera device, with all its registers but the one above in the camera device register space. For some weird reason a couple of bits were pushed to the control module, but that doesn't make the CSI2 PHY itself a separate device.

Yes they are separate. Anything in the system control module is a separate hardware module from the other devices. So in this case the CSI2 PHY is part of the system control module, not the camera module.

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2. Doing a read-back to flush a posted write in one hardware module most likely won't flush the write to other and that can lead into hard to find mysterious bugs

The OMAP4 ISS driver can just read back the CAMERA_RX register, can't it ?

Right, but you would have to do readbacks both from the phy register and camera register to ensure writes get written. It's best to keep the logic completely separate especially considering that they can be clocked separately.

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3. If we ever have a common system control module driver, we need to rewrite all the system control module register tinkering in the drivers

Sure, but that's already the case today, as the OMAP4 ISS driver already accesses the control module register directly. I won't make that worse :-)

Well it's in staging for a reason :)

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So it's best to try to use an existing framework for it. That avoids tons of pain later on ;)

Quoted 3 lines

I agree, but I don't think the PHY framework would be the right abstraction. As explained above the CSI2 PHY is part of the OMAP4 ISS, so modeling its single control module register as a PHY would be a hack.

Well that register belongs to the system control module, not the camera module. It's not like the camera IO space is out of registers or something! :)

We're already handling similar control module phy cases, see for example drivers/phy/phy-omap-control.c. Maybe you have most of the code already there?

Hi Tony,

Quoted 10 lines · On Friday 13 June 2014 00:53:25 Tony Lindgren wrote:

Quoted 8 lines · Laurent Pinchart

Quoted 1 line · On Thursday 12 June 2014 22:30:44 Tony Lindgren wrote:

1. They live in separate hardware modules that can be clocked separately

Actually I don't think that's true. The CSI2 PHY is part of the camera device, with all its registers but the one above in the camera device register space. For some weird reason a couple of bits were pushed to the control module, but that doesn't make the CSI2 PHY itself a separate device.

Quoted 4 lines

Yes they are separate. Anything in the system control module is a separate hardware module from the other devices. So in this case the CSI2 PHY is part of the system control module, not the camera module.

Section 8.2.3 ("ISS CSI2 PHY") of the OMAP4460 TRM (revision AA) documents the CSI2 PHY is being part of the ISS, with three PHY registers in the ISS register space (not counting the PHY interrupt and status bits in several other ISS registers) and one register in the system control module register space. It's far from clear which power domain(s) is (are) involved.

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2. Doing a read-back to flush a posted write in one hardware module most likely won't flush the write to other and that can lead into hard to find mysterious bugs

The OMAP4 ISS driver can just read back the CAMERA_RX register, can't it ?

Right, but you would have to do readbacks both from the phy register and camera register to ensure writes get written. It's best to keep the logic completely separate especially considering that they can be clocked separately.

Quoted 6 lines

Quoted 3 lines

3. If we ever have a common system control module driver, we need to rewrite all the system control module register tinkering in the drivers

Sure, but that's already the case today, as the OMAP4 ISS driver already accesses the control module register directly. I won't make that worse :-)

Well it's in staging for a reason :)

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So it's best to try to use an existing framework for it. That avoids tons of pain later on ;)

Quoted 7 lines

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I agree, but I don't think the PHY framework would be the right abstraction. As explained above the CSI2 PHY is part of the OMAP4 ISS, so modeling its single control module register as a PHY would be a hack.

Well that register belongs to the system control module, not the camera module. It's not like the camera IO space is out of registers or something! :)

The PHY has 3 registers in the ISS I/O space and one register in the control module I/O space. I have no idea why they've split it that way. The clock enable bits are especially "interested", the source clock (CAM_PHY_CTRL_FCLK) comes from the ISS as documented in section 8.1.1 ("ISS Integration"), is gated by the control module (the gated clock is called CTRLCLK) and then goes back to the ISS CSI2 PHY (it's mentioned in the CSI2 PHY "REGISTER1" documentation).

Quoted 3 lines

We're already handling similar control module phy cases, see for example drivers/phy/phy-omap-control.c. Maybe you have most of the code already there?

I'm afraid not. For PHYs that are in the system control module that solution is perfectly fine, but the CSI2 PHY isn't (or at least not all of it).

I would be fine with writing a separate PHY driver if the PHY was completely separate. As the documentation doesn't make it clear which part of the hardware belongs to which module, matching the software implementation with an unknown hardware implementation would be pretty difficult :-)

If you have a couple of minutes to spare and can look at the CSI2 PHY documentation in the TRM, you might be more successful than me figuring out how the hardware is implemented.

Quoted 17 lines · Laurent Pinchart

Quoted 11 lines · On Friday 13 June 2014 00:53:25 Tony Lindgren wrote:

Quoted 9 lines · Laurent Pinchart

Quoted 2 lines · On Thursday 12 June 2014 22:30:44 Tony Lindgren wrote:

1. They live in separate hardware modules that can be clocked separately

Actually I don't think that's true. The CSI2 PHY is part of the camera device, with all its registers but the one above in the camera device register space. For some weird reason a couple of bits were pushed to the control module, but that doesn't make the CSI2 PHY itself a separate device.

Quoted 4 lines

Yes they are separate. Anything in the system control module is a separate hardware module from the other devices. So in this case the CSI2 PHY is part of the system control module, not the camera module.

Quoted 6 lines

Section 8.2.3 ("ISS CSI2 PHY") of the OMAP4460 TRM (revision AA) documents the CSI2 PHY is being part of the ISS, with three PHY registers in the ISS register space (not counting the PHY interrupt and status bits in several other ISS registers) and one register in the system control module register space. It's far from clear which power domain(s) is (are) involved.

OK I see. The register in the system control module just contains some pin and clock related resources for the phy.

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2. Doing a read-back to flush a posted write in one hardware module most likely won't flush the write to other and that can lead into hard to find mysterious bugs

The OMAP4 ISS driver can just read back the CAMERA_RX register, can't it ?

Right, but you would have to do readbacks both from the phy register and camera register to ensure writes get written. It's best to keep the logic completely separate especially considering that they can be clocked separately.

Quoted 7 lines

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3. If we ever have a common system control module driver, we need to rewrite all the system control module register tinkering in the drivers

Sure, but that's already the case today, as the OMAP4 ISS driver already accesses the control module register directly. I won't make that worse :-)

Well it's in staging for a reason :)

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So it's best to try to use an existing framework for it. That avoids tons of pain later on ;)

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I agree, but I don't think the PHY framework would be the right abstraction. As explained above the CSI2 PHY is part of the OMAP4 ISS, so modeling its single control module register as a PHY would be a hack.

Well that register belongs to the system control module, not the camera module. It's not like the camera IO space is out of registers or something! :)

The PHY has 3 registers in the ISS I/O space and one register in the control module I/O space. I have no idea why they've split it that way. The clock enable bits are especially "interested", the source clock (CAM_PHY_CTRL_FCLK) comes from the ISS as documented in section 8.1.1 ("ISS Integration"), is gated by the control module (the gated clock is called CTRLCLK) and then goes back to the ISS CSI2 PHY (it's mentioned in the CSI2 PHY "REGISTER1" documentation).

Quoted 3 lines

We're already handling similar control module phy cases, see for example drivers/phy/phy-omap-control.c. Maybe you have most of the code already there?

I'm afraid not. For PHYs that are in the system control module that solution is perfectly fine, but the CSI2 PHY isn't (or at least not all of it).

Quoted 5 lines

I would be fine with writing a separate PHY driver if the PHY was completely separate. As the documentation doesn't make it clear which part of the hardware belongs to which module, matching the software implementation with an unknown hardware implementation would be pretty difficult :-)

Yeah it seems the phy driver would still have to use the pin resources in the system control module.

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If you have a couple of minutes to spare and can look at the CSI2 PHY documentation in the TRM, you might be more successful than me figuring out how the hardware is implemented.

Took a look and it seems the phy is split into two parts. So probably using the syscon mapping for the register in scm are is a good start. At least then there's some protection from drivers tinkering directly with the system control modules.

Maybe s ee what drivers/regulator/pbias-regulator.c is doing with
syscon to see if that works? Moving that to some phy driver later on should be trivial if needed :)