[PATCH 0/2] ARM: OMAP: mailbox out of plat code

[PATCH 0/2] ARM: OMAP: mailbox out of plat code

[Omar Ramirez Luna]

From: Omar Ramirez Luna <omar.ramirez@copitl.com>

Move Mailbox's headers and driver out of platform code as
per current plat-omap cleanup activities.

While at it move mailbox code out of platform and to drivers/
folder, given that this is an OMAP specific framework, some people
might frown upon this, however it seemed worth to try to move it now.
I was expecting this could also pull out the mailbox code from
ux-500 platform, but the platform with a similar mailbox mechanism
has been deleted during 3.5 rc cycle.

So, are there any other mailbox-like drivers out there?

Omar Ramirez Luna (2):
  ARM: OMAP2+: move mailbox.h out of plat-omap headers
  mailbox: OMAP: introduce mailbox framework

 arch/arm/mach-omap2/mailbox.c                      |    2 +-
 arch/arm/plat-omap/Kconfig                         |   16 -
 arch/arm/plat-omap/Makefile                        |    3 -
 arch/arm/plat-omap/include/plat/mailbox.h          |  105 -----
 arch/arm/plat-omap/mailbox.c                       |  435 --------------------
 drivers/Kconfig                                    |    2 +
 drivers/Makefile                                   |    1 +
 drivers/mailbox/Kconfig                            |   28 ++
 drivers/mailbox/Makefile                           |    1 +
 drivers/mailbox/mailbox.c                          |  435 ++++++++++++++++++++
 .../tidspbridge/include/dspbridge/host_os.h        |    2 +-
 include/linux/platform_data/omap_mailbox.h         |  105 +++++
 12 files changed, 574 insertions(+), 561 deletions(-)
 delete mode 100644 arch/arm/plat-omap/include/plat/mailbox.h
 delete mode 100644 arch/arm/plat-omap/mailbox.c
 create mode 100644 drivers/mailbox/Kconfig
 create mode 100644 drivers/mailbox/Makefile
 create mode 100644 drivers/mailbox/mailbox.c
 create mode 100644 include/linux/platform_data/omap_mailbox.h

-- 
1.7.9.5

[PATCH 1/2] ARM: OMAP2+: move mailbox.h out of plat-omap headers

[Omar Ramirez Luna]

CC: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
CC: devel@driverdev.osuosl.org
Signed-off-by: Omar Ramirez Luna <omar.luna@linaro.org>
---
 arch/arm/mach-omap2/mailbox.c                      |    2 +-
 arch/arm/plat-omap/include/plat/mailbox.h          |  105 --------------------
 arch/arm/plat-omap/mailbox.c                       |    2 +-
 .../tidspbridge/include/dspbridge/host_os.h        |    2 +-
 include/linux/platform_data/omap_mailbox.h         |  105 ++++++++++++++++++++
 5 files changed, 108 insertions(+), 108 deletions(-)
 delete mode 100644 arch/arm/plat-omap/include/plat/mailbox.h
 create mode 100644 include/linux/platform_data/omap_mailbox.h

diff --git a/arch/arm/mach-omap2/mailbox.c b/arch/arm/mach-omap2/mailbox.c
index 0d97456..f69e659 100644
--- a/arch/arm/mach-omap2/mailbox.c
+++ b/arch/arm/mach-omap2/mailbox.c
@@ -17,7 +17,7 @@
 #include <linux/io.h>
 #include <linux/pm_runtime.h>
 
-#include <plat/mailbox.h>
+#include <linux/platform_data/omap_mailbox.h>
 
 #include "soc.h"
 
diff --git a/arch/arm/plat-omap/include/plat/mailbox.h b/arch/arm/plat-omap/include/plat/mailbox.h
deleted file mode 100644
index cc3921e..0000000
--- a/arch/arm/plat-omap/include/plat/mailbox.h
+++ /dev/null
@@ -1,105 +0,0 @@
-/* mailbox.h */
-
-#ifndef MAILBOX_H
-#define MAILBOX_H
-
-#include <linux/spinlock.h>
-#include <linux/workqueue.h>
-#include <linux/interrupt.h>
-#include <linux/device.h>
-#include <linux/kfifo.h>
-
-typedef u32 mbox_msg_t;
-struct omap_mbox;
-
-typedef int __bitwise omap_mbox_irq_t;
-#define IRQ_TX ((__force omap_mbox_irq_t) 1)
-#define IRQ_RX ((__force omap_mbox_irq_t) 2)
-
-typedef int __bitwise omap_mbox_type_t;
-#define OMAP_MBOX_TYPE1 ((__force omap_mbox_type_t) 1)
-#define OMAP_MBOX_TYPE2 ((__force omap_mbox_type_t) 2)
-
-struct omap_mbox_ops {
-	omap_mbox_type_t	type;
-	int		(*startup)(struct omap_mbox *mbox);
-	void		(*shutdown)(struct omap_mbox *mbox);
-	/* fifo */
-	mbox_msg_t	(*fifo_read)(struct omap_mbox *mbox);
-	void		(*fifo_write)(struct omap_mbox *mbox, mbox_msg_t msg);
-	int		(*fifo_empty)(struct omap_mbox *mbox);
-	int		(*fifo_full)(struct omap_mbox *mbox);
-	/* irq */
-	void		(*enable_irq)(struct omap_mbox *mbox,
-						omap_mbox_irq_t irq);
-	void		(*disable_irq)(struct omap_mbox *mbox,
-						omap_mbox_irq_t irq);
-	void		(*ack_irq)(struct omap_mbox *mbox, omap_mbox_irq_t irq);
-	int		(*is_irq)(struct omap_mbox *mbox, omap_mbox_irq_t irq);
-	/* ctx */
-	void		(*save_ctx)(struct omap_mbox *mbox);
-	void		(*restore_ctx)(struct omap_mbox *mbox);
-};
-
-struct omap_mbox_queue {
-	spinlock_t		lock;
-	struct kfifo		fifo;
-	struct work_struct	work;
-	struct tasklet_struct	tasklet;
-	struct omap_mbox	*mbox;
-	bool full;
-};
-
-struct omap_mbox {
-	char			*name;
-	unsigned int		irq;
-	struct omap_mbox_queue	*txq, *rxq;
-	struct omap_mbox_ops	*ops;
-	struct device		*dev;
-	void			*priv;
-	int			use_count;
-	struct blocking_notifier_head   notifier;
-};
-
-int omap_mbox_msg_send(struct omap_mbox *, mbox_msg_t msg);
-void omap_mbox_init_seq(struct omap_mbox *);
-
-struct omap_mbox *omap_mbox_get(const char *, struct notifier_block *nb);
-void omap_mbox_put(struct omap_mbox *mbox, struct notifier_block *nb);
-
-int omap_mbox_register(struct device *parent, struct omap_mbox **);
-int omap_mbox_unregister(void);
-
-static inline void omap_mbox_save_ctx(struct omap_mbox *mbox)
-{
-	if (!mbox->ops->save_ctx) {
-		dev_err(mbox->dev, "%s:\tno save\n", __func__);
-		return;
-	}
-
-	mbox->ops->save_ctx(mbox);
-}
-
-static inline void omap_mbox_restore_ctx(struct omap_mbox *mbox)
-{
-	if (!mbox->ops->restore_ctx) {
-		dev_err(mbox->dev, "%s:\tno restore\n", __func__);
-		return;
-	}
-
-	mbox->ops->restore_ctx(mbox);
-}
-
-static inline void omap_mbox_enable_irq(struct omap_mbox *mbox,
-					omap_mbox_irq_t irq)
-{
-	mbox->ops->enable_irq(mbox, irq);
-}
-
-static inline void omap_mbox_disable_irq(struct omap_mbox *mbox,
-					 omap_mbox_irq_t irq)
-{
-	mbox->ops->disable_irq(mbox, irq);
-}
-
-#endif /* MAILBOX_H */
diff --git a/arch/arm/plat-omap/mailbox.c b/arch/arm/plat-omap/mailbox.c
index 42377ef..cae8692 100644
--- a/arch/arm/plat-omap/mailbox.c
+++ b/arch/arm/plat-omap/mailbox.c
@@ -31,7 +31,7 @@
 #include <linux/notifier.h>
 #include <linux/module.h>
 
-#include <plat/mailbox.h>
+#include <linux/platform_data/omap_mailbox.h>
 
 static struct omap_mbox **mboxes;
 
diff --git a/drivers/staging/tidspbridge/include/dspbridge/host_os.h b/drivers/staging/tidspbridge/include/dspbridge/host_os.h
index 896f157..bff9e3a 100644
--- a/drivers/staging/tidspbridge/include/dspbridge/host_os.h
+++ b/drivers/staging/tidspbridge/include/dspbridge/host_os.h
@@ -41,11 +41,11 @@
 #include <linux/ioport.h>
 #include <linux/platform_device.h>
 #include <linux/clk.h>
-#include <plat/mailbox.h>
 #include <linux/pagemap.h>
 #include <asm/cacheflush.h>
 #include <linux/dma-mapping.h>
 
+#include <linux/platform_data/omap_mailbox.h>
 /* TODO -- Remove, once BP defines them */
 #define INT_DSP_MMU_IRQ        28
 
diff --git a/include/linux/platform_data/omap_mailbox.h b/include/linux/platform_data/omap_mailbox.h
new file mode 100644
index 0000000..cc3921e
--- /dev/null
+++ b/include/linux/platform_data/omap_mailbox.h
@@ -0,0 +1,105 @@
+/* mailbox.h */
+
+#ifndef MAILBOX_H
+#define MAILBOX_H
+
+#include <linux/spinlock.h>
+#include <linux/workqueue.h>
+#include <linux/interrupt.h>
+#include <linux/device.h>
+#include <linux/kfifo.h>
+
+typedef u32 mbox_msg_t;
+struct omap_mbox;
+
+typedef int __bitwise omap_mbox_irq_t;
+#define IRQ_TX ((__force omap_mbox_irq_t) 1)
+#define IRQ_RX ((__force omap_mbox_irq_t) 2)
+
+typedef int __bitwise omap_mbox_type_t;
+#define OMAP_MBOX_TYPE1 ((__force omap_mbox_type_t) 1)
+#define OMAP_MBOX_TYPE2 ((__force omap_mbox_type_t) 2)
+
+struct omap_mbox_ops {
+	omap_mbox_type_t	type;
+	int		(*startup)(struct omap_mbox *mbox);
+	void		(*shutdown)(struct omap_mbox *mbox);
+	/* fifo */
+	mbox_msg_t	(*fifo_read)(struct omap_mbox *mbox);
+	void		(*fifo_write)(struct omap_mbox *mbox, mbox_msg_t msg);
+	int		(*fifo_empty)(struct omap_mbox *mbox);
+	int		(*fifo_full)(struct omap_mbox *mbox);
+	/* irq */
+	void		(*enable_irq)(struct omap_mbox *mbox,
+						omap_mbox_irq_t irq);
+	void		(*disable_irq)(struct omap_mbox *mbox,
+						omap_mbox_irq_t irq);
+	void		(*ack_irq)(struct omap_mbox *mbox, omap_mbox_irq_t irq);
+	int		(*is_irq)(struct omap_mbox *mbox, omap_mbox_irq_t irq);
+	/* ctx */
+	void		(*save_ctx)(struct omap_mbox *mbox);
+	void		(*restore_ctx)(struct omap_mbox *mbox);
+};
+
+struct omap_mbox_queue {
+	spinlock_t		lock;
+	struct kfifo		fifo;
+	struct work_struct	work;
+	struct tasklet_struct	tasklet;
+	struct omap_mbox	*mbox;
+	bool full;
+};
+
+struct omap_mbox {
+	char			*name;
+	unsigned int		irq;
+	struct omap_mbox_queue	*txq, *rxq;
+	struct omap_mbox_ops	*ops;
+	struct device		*dev;
+	void			*priv;
+	int			use_count;
+	struct blocking_notifier_head   notifier;
+};
+
+int omap_mbox_msg_send(struct omap_mbox *, mbox_msg_t msg);
+void omap_mbox_init_seq(struct omap_mbox *);
+
+struct omap_mbox *omap_mbox_get(const char *, struct notifier_block *nb);
+void omap_mbox_put(struct omap_mbox *mbox, struct notifier_block *nb);
+
+int omap_mbox_register(struct device *parent, struct omap_mbox **);
+int omap_mbox_unregister(void);
+
+static inline void omap_mbox_save_ctx(struct omap_mbox *mbox)
+{
+	if (!mbox->ops->save_ctx) {
+		dev_err(mbox->dev, "%s:\tno save\n", __func__);
+		return;
+	}
+
+	mbox->ops->save_ctx(mbox);
+}
+
+static inline void omap_mbox_restore_ctx(struct omap_mbox *mbox)
+{
+	if (!mbox->ops->restore_ctx) {
+		dev_err(mbox->dev, "%s:\tno restore\n", __func__);
+		return;
+	}
+
+	mbox->ops->restore_ctx(mbox);
+}
+
+static inline void omap_mbox_enable_irq(struct omap_mbox *mbox,
+					omap_mbox_irq_t irq)
+{
+	mbox->ops->enable_irq(mbox, irq);
+}
+
+static inline void omap_mbox_disable_irq(struct omap_mbox *mbox,
+					 omap_mbox_irq_t irq)
+{
+	mbox->ops->disable_irq(mbox, irq);
+}
+
+#endif /* MAILBOX_H */
-- 
1.7.9.5

Re: [PATCH 1/2] ARM: OMAP2+: move mailbox.h out of plat-omap headers

[Tony Lindgren]

Hi,

> --- /dev/null
> +++ b/include/linux/platform_data/omap_mailbox.h
> @@ -0,0 +1,105 @@

This file should only contain pure platform data needed
by the core omap code to pass to the mailbox driver.

The mailbox API header should be somewhere else,
like include/linux/mailbox/mailbox-omap.h or similar.

But shouldn't this all now be handled by using the
remoteproc framework?

Regards,

Tony

Re: [PATCH 1/2] ARM: OMAP2+: move mailbox.h out of plat-omap headers

[Omar Ramirez Luna]

Tony,

On 29 October 2012 12:52, Tony Lindgren <tony@atomide.com> wrote:
>> --- /dev/null
>> +++ b/include/linux/platform_data/omap_mailbox.h
>> @@ -0,0 +1,105 @@
>
> This file should only contain pure platform data needed
> by the core omap code to pass to the mailbox driver.

Ok, looking at it closely, this header file is related to the API
itself, there is nothing that could be actually considered as pure
platform data, the structures are related with the mailbox framework
and even if I split this file into two, the additional header would
end up including the "platform_data" header unless I move
save/restore_ctx functions and then export them as symbols for the
API.

So, it might be better for the entire file to sit in
linux/include/mailbox/ then.

> The mailbox API header should be somewhere else,
> like include/linux/mailbox/mailbox-omap.h or similar.

Ok.

> But shouldn't this all now be handled by using the
> remoteproc framework?

Remoteproc doesn't handle the mailbox hardware directly, it still
relies in the mailbox framework for the low level communications.
E.g.: Proc1 has a message (virtqueue msg) queued to Proc2, uses
mailbox msg to generate an interrupt to Proc2, Proc2 queries the
message (virtqueue) based on the mailbox message received.

Regards,

Omar

Re: [PATCH 1/2] ARM: OMAP2+: move mailbox.h out of plat-omap headers

[Tony Lindgren]

* Omar Ramirez Luna <omar.luna@linaro.org> [121030 05:20]:
> Tony,
> 
> On 29 October 2012 12:52, Tony Lindgren <tony@atomide.com> wrote:
> >> --- /dev/null
> >> +++ b/include/linux/platform_data/omap_mailbox.h
> >> @@ -0,0 +1,105 @@
> >
> > This file should only contain pure platform data needed
> > by the core omap code to pass to the mailbox driver.
> 
> Ok, looking at it closely, this header file is related to the API
> itself, there is nothing that could be actually considered as pure
> platform data, the structures are related with the mailbox framework
> and even if I split this file into two, the additional header would
> end up including the "platform_data" header unless I move
> save/restore_ctx functions and then export them as symbols for the
> API.
> 
> So, it might be better for the entire file to sit in
> linux/include/mailbox/ then.

OK to me.
 
> > The mailbox API header should be somewhere else,
> > like include/linux/mailbox/mailbox-omap.h or similar.
> 
> Ok.
> 
> > But shouldn't this all now be handled by using the
> > remoteproc framework?
> 
> Remoteproc doesn't handle the mailbox hardware directly, it still
> relies in the mailbox framework for the low level communications.
> E.g.: Proc1 has a message (virtqueue msg) queued to Proc2, uses
> mailbox msg to generate an interrupt to Proc2, Proc2 queries the
> message (virtqueue) based on the mailbox message received.

OK.

Greg, do these patches look OK to you to move to live under
drivers/mailbox?

Regards,

Tony

Re: [PATCH 1/2] ARM: OMAP2+: move mailbox.h out of plat-omap headers

[Greg Kroah-Hartman]

On Tue, Oct 30, 2012 at 09:24:42AM -0700, Tony Lindgren wrote:
> * Omar Ramirez Luna <omar.luna@linaro.org> [121030 05:20]:
> > Tony,
> > 
> > On 29 October 2012 12:52, Tony Lindgren <tony@atomide.com> wrote:
> > >> --- /dev/null
> > >> +++ b/include/linux/platform_data/omap_mailbox.h
> > >> @@ -0,0 +1,105 @@
> > >
> > > This file should only contain pure platform data needed
> > > by the core omap code to pass to the mailbox driver.
> > 
> > Ok, looking at it closely, this header file is related to the API
> > itself, there is nothing that could be actually considered as pure
> > platform data, the structures are related with the mailbox framework
> > and even if I split this file into two, the additional header would
> > end up including the "platform_data" header unless I move
> > save/restore_ctx functions and then export them as symbols for the
> > API.
> > 
> > So, it might be better for the entire file to sit in
> > linux/include/mailbox/ then.
> 
> OK to me.
>  
> > > The mailbox API header should be somewhere else,
> > > like include/linux/mailbox/mailbox-omap.h or similar.
> > 
> > Ok.
> > 
> > > But shouldn't this all now be handled by using the
> > > remoteproc framework?
> > 
> > Remoteproc doesn't handle the mailbox hardware directly, it still
> > relies in the mailbox framework for the low level communications.
> > E.g.: Proc1 has a message (virtqueue msg) queued to Proc2, uses
> > mailbox msg to generate an interrupt to Proc2, Proc2 queries the
> > message (virtqueue) based on the mailbox message received.
> 
> OK.
> 
> Greg, do these patches look OK to you to move to live under
> drivers/mailbox?

Um, I don't know, I wasn't paying attention here, sorry.

greg k-h

Re: [PATCH 1/2] ARM: OMAP2+: move mailbox.h out of plat-omap headers

[Omar Ramirez Luna]

Hi Greg,

On 30 October 2012 16:02, Greg Kroah-Hartman <gregkh@linuxfoundation.org> wrote:
>> OK.
>>
>> Greg, do these patches look OK to you to move to live under
>> drivers/mailbox?
>
> Um, I don't know, I wasn't paying attention here, sorry.

As part of plat-omap code cleanup, I was planning to move omap-mailbox
framework to a newly drivers/mailbox folder, right now this code is
specific to OMAP platforms, but with some clean up it could be the
base for a generic framework. And living under drivers/mailbox could
give it some exposure for interested developers to give feedback and
propose changes.

In the past there was a mailbox-like driver in mach-ux500, I was
hoping both could live under the same folder, however the platform
using it, was dropped a couple of kernel releases back and with it the
other similar mailbox implementation.

So, here it is the thread with the patches:
http://thread.gmane.org/gmane.linux.kernel/1384603, if you think it is
OK for them to be moved under drivers/mailbox, I just need to re-spin
them to move the mailbox header file to include/linux/mailbox instead
of include/linux/platform_data.

Cheers,

Omar

Re: [PATCH 1/2] ARM: OMAP2+: move mailbox.h out of plat-omap headers

[Loic PALLARDY]

Hi Omar,

On 10/31/2012 08:22 AM, Omar Ramirez Luna wrote:
>
> As part of plat-omap code cleanup, I was planning to move omap-mailbox
> framework to a newly drivers/mailbox folder, right now this code is
> specific to OMAP platforms, but with some clean up it could be the
> base for a generic framework. And living under drivers/mailbox could
> give it some exposure for interested developers to give feedback and
> propose changes.
>
> In the past there was a mailbox-like driver in mach-ux500, I was
> hoping both could live under the same folder, however the platform
> using it, was dropped a couple of kernel releases back and with it the
> other similar mailbox implementation.

On STE side, we are working on a mailbox driver which will rely on 
mailbox framework.
However some modifications in current Omap mailbox framework are needed 
to fit STE HW specificities.
- API naming should be generic (replace omap prefix by mailbox)
- message type should be enhanced
- fifo mechanism is linked to Omap maibox, not needed in STE case since 
it relies on cross interrupt + shared memory
I already have modifications I'll send you to see how we can create a 
common and generic mailbox framework.

Regards
Loic

Re: [PATCH 1/2] ARM: OMAP2+: move mailbox.h out of plat-omap headers

[Tony Lindgren]

* Loic PALLARDY <loic.pallardy@st.com> [121031 01:48]:
> 
> Hi Omar,
> 
> On 10/31/2012 08:22 AM, Omar Ramirez Luna wrote:
> >
> > As part of plat-omap code cleanup, I was planning to move omap-mailbox
> > framework to a newly drivers/mailbox folder, right now this code is
> > specific to OMAP platforms, but with some clean up it could be the
> > base for a generic framework. And living under drivers/mailbox could
> > give it some exposure for interested developers to give feedback and
> > propose changes.
> >
> > In the past there was a mailbox-like driver in mach-ux500, I was
> > hoping both could live under the same folder, however the platform
> > using it, was dropped a couple of kernel releases back and with it the
> > other similar mailbox implementation.
> 
> On STE side, we are working on a mailbox driver which will rely on 
> mailbox framework.
> However some modifications in current Omap mailbox framework are needed 
> to fit STE HW specificities.
> - API naming should be generic (replace omap prefix by mailbox)
> - message type should be enhanced
> - fifo mechanism is linked to Omap maibox, not needed in STE case since 
> it relies on cross interrupt + shared memory
> I already have modifications I'll send you to see how we can create a 
> common and generic mailbox framework.

OK cool. How about Omar first posts the fixed minimal patches
to move things to live under drivers so can fix up omap for
ARCH_MULTIPLATFORM?

I can then put just those into an immutable branch that people
can pull in as needed, and you guys can continue from there with
the common mailbox framework (and I can continue work on the
core omap code independently of the mailbox framwork work).

Regards,

Tony

[PATCH 2/2] mailbox: OMAP: introduce mailbox framework

[Omar Ramirez Luna]

Actually moving it from plat-omap code as this is supposed to be
under drivers/ folder. This framework should work with the current
OMAP processors that have mailbox and can be used as a method of
interprocessor communication.

Signed-off-by: Omar Ramirez Luna <omar.luna@linaro.org>
---
 arch/arm/plat-omap/Kconfig   |   16 --
 arch/arm/plat-omap/Makefile  |    3 -
 arch/arm/plat-omap/mailbox.c |  435 ------------------------------------------
 drivers/Kconfig              |    2 +
 drivers/Makefile             |    1 +
 drivers/mailbox/Kconfig      |   28 +++
 drivers/mailbox/Makefile     |    1 +
 drivers/mailbox/mailbox.c    |  435 ++++++++++++++++++++++++++++++++++++++++++
 8 files changed, 467 insertions(+), 454 deletions(-)
 delete mode 100644 arch/arm/plat-omap/mailbox.c
 create mode 100644 drivers/mailbox/Kconfig
 create mode 100644 drivers/mailbox/Makefile
 create mode 100644 drivers/mailbox/mailbox.c

diff --git a/arch/arm/plat-omap/Kconfig b/arch/arm/plat-omap/Kconfig
index 82fcb20..419648f 100644
--- a/arch/arm/plat-omap/Kconfig
+++ b/arch/arm/plat-omap/Kconfig
@@ -116,22 +116,6 @@ config OMAP_MUX_WARNINGS
 	  to change the pin multiplexing setup.	 When there are no warnings
 	  printed, it's safe to deselect OMAP_MUX for your product.
 
-config OMAP_MBOX_FWK
-	tristate "Mailbox framework support"
-	depends on ARCH_OMAP
-	help
-	  Say Y here if you want to use OMAP Mailbox framework support for
-	  DSP, IVA1.0 and IVA2 in OMAP1/2/3.
-
-config OMAP_MBOX_KFIFO_SIZE
-	int "Mailbox kfifo default buffer size (bytes)"
-	depends on OMAP_MBOX_FWK
-	default 256
-	help
-	  Specify the default size of mailbox's kfifo buffers (bytes).
-	  This can also be changed at runtime (via the mbox_kfifo_size
-	  module parameter).
-
 config OMAP_IOMMU_IVA2
 	bool
 
diff --git a/arch/arm/plat-omap/Makefile b/arch/arm/plat-omap/Makefile
index 4bd0ace..4702d1f 100644
--- a/arch/arm/plat-omap/Makefile
+++ b/arch/arm/plat-omap/Makefile
@@ -16,7 +16,4 @@ obj-$(CONFIG_OMAP_DEBUG_LEDS) += debug-leds.o
 i2c-omap-$(CONFIG_I2C_OMAP) := i2c.o
 obj-y += $(i2c-omap-m) $(i2c-omap-y)
 
-# OMAP mailbox framework
-obj-$(CONFIG_OMAP_MBOX_FWK) += mailbox.o
-
 obj-$(CONFIG_OMAP_PM_NOOP) += omap-pm-noop.o
diff --git a/arch/arm/plat-omap/mailbox.c b/arch/arm/plat-omap/mailbox.c
deleted file mode 100644
index cae8692..0000000
--- a/arch/arm/plat-omap/mailbox.c
+++ /dev/null
@@ -1,435 +0,0 @@
-/*
- * OMAP mailbox driver
- *
- * Copyright (C) 2006-2009 Nokia Corporation. All rights reserved.
- *
- * Contact: Hiroshi DOYU <Hiroshi.DOYU@nokia.com>
- *
- * This program is free software; you can redistribute it and/or
- * modify it under the terms of the GNU General Public License
- * version 2 as published by the Free Software Foundation.
- *
- * This program is distributed in the hope that it will be useful, but
- * WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
- * General Public License for more details.
- *
- * You should have received a copy of the GNU General Public License
- * along with this program; if not, write to the Free Software
- * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA
- * 02110-1301 USA
- *
- */
-
-#include <linux/interrupt.h>
-#include <linux/spinlock.h>
-#include <linux/mutex.h>
-#include <linux/delay.h>
-#include <linux/slab.h>
-#include <linux/kfifo.h>
-#include <linux/err.h>
-#include <linux/notifier.h>
-#include <linux/module.h>
-
-#include <linux/platform_data/omap_mailbox.h>
-
-static struct omap_mbox **mboxes;
-
-static int mbox_configured;
-static DEFINE_MUTEX(mbox_configured_lock);
-
-static unsigned int mbox_kfifo_size = CONFIG_OMAP_MBOX_KFIFO_SIZE;
-module_param(mbox_kfifo_size, uint, S_IRUGO);
-MODULE_PARM_DESC(mbox_kfifo_size, "Size of omap's mailbox kfifo (bytes)");
-
-/* Mailbox FIFO handle functions */
-static inline mbox_msg_t mbox_fifo_read(struct omap_mbox *mbox)
-{
-	return mbox->ops->fifo_read(mbox);
-}
-static inline void mbox_fifo_write(struct omap_mbox *mbox, mbox_msg_t msg)
-{
-	mbox->ops->fifo_write(mbox, msg);
-}
-static inline int mbox_fifo_empty(struct omap_mbox *mbox)
-{
-	return mbox->ops->fifo_empty(mbox);
-}
-static inline int mbox_fifo_full(struct omap_mbox *mbox)
-{
-	return mbox->ops->fifo_full(mbox);
-}
-
-/* Mailbox IRQ handle functions */
-static inline void ack_mbox_irq(struct omap_mbox *mbox, omap_mbox_irq_t irq)
-{
-	if (mbox->ops->ack_irq)
-		mbox->ops->ack_irq(mbox, irq);
-}
-static inline int is_mbox_irq(struct omap_mbox *mbox, omap_mbox_irq_t irq)
-{
-	return mbox->ops->is_irq(mbox, irq);
-}
-
-/*
- * message sender
- */
-static int __mbox_poll_for_space(struct omap_mbox *mbox)
-{
-	int ret = 0, i = 1000;
-
-	while (mbox_fifo_full(mbox)) {
-		if (mbox->ops->type == OMAP_MBOX_TYPE2)
-			return -1;
-		if (--i == 0)
-			return -1;
-		udelay(1);
-	}
-	return ret;
-}
-
-int omap_mbox_msg_send(struct omap_mbox *mbox, mbox_msg_t msg)
-{
-	struct omap_mbox_queue *mq = mbox->txq;
-	int ret = 0, len;
-
-	spin_lock_bh(&mq->lock);
-
-	if (kfifo_avail(&mq->fifo) < sizeof(msg)) {
-		ret = -ENOMEM;
-		goto out;
-	}
-
-	if (kfifo_is_empty(&mq->fifo) && !__mbox_poll_for_space(mbox)) {
-		mbox_fifo_write(mbox, msg);
-		goto out;
-	}
-
-	len = kfifo_in(&mq->fifo, (unsigned char *)&msg, sizeof(msg));
-	WARN_ON(len != sizeof(msg));
-
-	tasklet_schedule(&mbox->txq->tasklet);
-
-out:
-	spin_unlock_bh(&mq->lock);
-	return ret;
-}
-EXPORT_SYMBOL(omap_mbox_msg_send);
-
-static void mbox_tx_tasklet(unsigned long tx_data)
-{
-	struct omap_mbox *mbox = (struct omap_mbox *)tx_data;
-	struct omap_mbox_queue *mq = mbox->txq;
-	mbox_msg_t msg;
-	int ret;
-
-	while (kfifo_len(&mq->fifo)) {
-		if (__mbox_poll_for_space(mbox)) {
-			omap_mbox_enable_irq(mbox, IRQ_TX);
-			break;
-		}
-
-		ret = kfifo_out(&mq->fifo, (unsigned char *)&msg,
-								sizeof(msg));
-		WARN_ON(ret != sizeof(msg));
-
-		mbox_fifo_write(mbox, msg);
-	}
-}
-
-/*
- * Message receiver(workqueue)
- */
-static void mbox_rx_work(struct work_struct *work)
-{
-	struct omap_mbox_queue *mq =
-			container_of(work, struct omap_mbox_queue, work);
-	mbox_msg_t msg;
-	int len;
-
-	while (kfifo_len(&mq->fifo) >= sizeof(msg)) {
-		len = kfifo_out(&mq->fifo, (unsigned char *)&msg, sizeof(msg));
-		WARN_ON(len != sizeof(msg));
-
-		blocking_notifier_call_chain(&mq->mbox->notifier, len,
-								(void *)msg);
-		spin_lock_irq(&mq->lock);
-		if (mq->full) {
-			mq->full = false;
-			omap_mbox_enable_irq(mq->mbox, IRQ_RX);
-		}
-		spin_unlock_irq(&mq->lock);
-	}
-}
-
-/*
- * Mailbox interrupt handler
- */
-static void __mbox_tx_interrupt(struct omap_mbox *mbox)
-{
-	omap_mbox_disable_irq(mbox, IRQ_TX);
-	ack_mbox_irq(mbox, IRQ_TX);
-	tasklet_schedule(&mbox->txq->tasklet);
-}
-
-static void __mbox_rx_interrupt(struct omap_mbox *mbox)
-{
-	struct omap_mbox_queue *mq = mbox->rxq;
-	mbox_msg_t msg;
-	int len;
-
-	while (!mbox_fifo_empty(mbox)) {
-		if (unlikely(kfifo_avail(&mq->fifo) < sizeof(msg))) {
-			omap_mbox_disable_irq(mbox, IRQ_RX);
-			mq->full = true;
-			goto nomem;
-		}
-
-		msg = mbox_fifo_read(mbox);
-
-		len = kfifo_in(&mq->fifo, (unsigned char *)&msg, sizeof(msg));
-		WARN_ON(len != sizeof(msg));
-
-		if (mbox->ops->type == OMAP_MBOX_TYPE1)
-			break;
-	}
-
-	/* no more messages in the fifo. clear IRQ source. */
-	ack_mbox_irq(mbox, IRQ_RX);
-nomem:
-	schedule_work(&mbox->rxq->work);
-}
-
-static irqreturn_t mbox_interrupt(int irq, void *p)
-{
-	struct omap_mbox *mbox = p;
-
-	if (is_mbox_irq(mbox, IRQ_TX))
-		__mbox_tx_interrupt(mbox);
-
-	if (is_mbox_irq(mbox, IRQ_RX))
-		__mbox_rx_interrupt(mbox);
-
-	return IRQ_HANDLED;
-}
-
-static struct omap_mbox_queue *mbox_queue_alloc(struct omap_mbox *mbox,
-					void (*work) (struct work_struct *),
-					void (*tasklet)(unsigned long))
-{
-	struct omap_mbox_queue *mq;
-
-	mq = kzalloc(sizeof(struct omap_mbox_queue), GFP_KERNEL);
-	if (!mq)
-		return NULL;
-
-	spin_lock_init(&mq->lock);
-
-	if (kfifo_alloc(&mq->fifo, mbox_kfifo_size, GFP_KERNEL))
-		goto error;
-
-	if (work)
-		INIT_WORK(&mq->work, work);
-
-	if (tasklet)
-		tasklet_init(&mq->tasklet, tasklet, (unsigned long)mbox);
-	return mq;
-error:
-	kfree(mq);
-	return NULL;
-}
-
-static void mbox_queue_free(struct omap_mbox_queue *q)
-{
-	kfifo_free(&q->fifo);
-	kfree(q);
-}
-
-static int omap_mbox_startup(struct omap_mbox *mbox)
-{
-	int ret = 0;
-	struct omap_mbox_queue *mq;
-
-	mutex_lock(&mbox_configured_lock);
-	if (!mbox_configured++) {
-		if (likely(mbox->ops->startup)) {
-			ret = mbox->ops->startup(mbox);
-			if (unlikely(ret))
-				goto fail_startup;
-		} else
-			goto fail_startup;
-	}
-
-	if (!mbox->use_count++) {
-		ret = request_irq(mbox->irq, mbox_interrupt, IRQF_SHARED,
-							mbox->name, mbox);
-		if (unlikely(ret)) {
-			pr_err("failed to register mailbox interrupt:%d\n",
-									ret);
-			goto fail_request_irq;
-		}
-		mq = mbox_queue_alloc(mbox, NULL, mbox_tx_tasklet);
-		if (!mq) {
-			ret = -ENOMEM;
-			goto fail_alloc_txq;
-		}
-		mbox->txq = mq;
-
-		mq = mbox_queue_alloc(mbox, mbox_rx_work, NULL);
-		if (!mq) {
-			ret = -ENOMEM;
-			goto fail_alloc_rxq;
-		}
-		mbox->rxq = mq;
-		mq->mbox = mbox;
-
-		omap_mbox_enable_irq(mbox, IRQ_RX);
-	}
-	mutex_unlock(&mbox_configured_lock);
-	return 0;
-
-fail_alloc_rxq:
-	mbox_queue_free(mbox->txq);
-fail_alloc_txq:
-	free_irq(mbox->irq, mbox);
-fail_request_irq:
-	if (mbox->ops->shutdown)
-		mbox->ops->shutdown(mbox);
-	mbox->use_count--;
-fail_startup:
-	mbox_configured--;
-	mutex_unlock(&mbox_configured_lock);
-	return ret;
-}
-
-static void omap_mbox_fini(struct omap_mbox *mbox)
-{
-	mutex_lock(&mbox_configured_lock);
-
-	if (!--mbox->use_count) {
-		omap_mbox_disable_irq(mbox, IRQ_RX);
-		free_irq(mbox->irq, mbox);
-		tasklet_kill(&mbox->txq->tasklet);
-		flush_work(&mbox->rxq->work);
-		mbox_queue_free(mbox->txq);
-		mbox_queue_free(mbox->rxq);
-	}
-
-	if (likely(mbox->ops->shutdown)) {
-		if (!--mbox_configured)
-			mbox->ops->shutdown(mbox);
-	}
-
-	mutex_unlock(&mbox_configured_lock);
-}
-
-struct omap_mbox *omap_mbox_get(const char *name, struct notifier_block *nb)
-{
-	struct omap_mbox *_mbox, *mbox = NULL;
-	int i, ret;
-
-	if (!mboxes)
-		return ERR_PTR(-EINVAL);
-
-	for (i = 0; (_mbox = mboxes[i]); i++) {
-		if (!strcmp(_mbox->name, name)) {
-			mbox = _mbox;
-			break;
-		}
-	}
-
-	if (!mbox)
-		return ERR_PTR(-ENOENT);
-
-	if (nb)
-		blocking_notifier_chain_register(&mbox->notifier, nb);
-
-	ret = omap_mbox_startup(mbox);
-	if (ret) {
-		blocking_notifier_chain_unregister(&mbox->notifier, nb);
-		return ERR_PTR(-ENODEV);
-	}
-
-	return mbox;
-}
-EXPORT_SYMBOL(omap_mbox_get);
-
-void omap_mbox_put(struct omap_mbox *mbox, struct notifier_block *nb)
-{
-	blocking_notifier_chain_unregister(&mbox->notifier, nb);
-	omap_mbox_fini(mbox);
-}
-EXPORT_SYMBOL(omap_mbox_put);
-
-static struct class omap_mbox_class = { .name = "mbox", };
-
-int omap_mbox_register(struct device *parent, struct omap_mbox **list)
-{
-	int ret;
-	int i;
-
-	mboxes = list;
-	if (!mboxes)
-		return -EINVAL;
-
-	for (i = 0; mboxes[i]; i++) {
-		struct omap_mbox *mbox = mboxes[i];
-		mbox->dev = device_create(&omap_mbox_class,
-				parent, 0, mbox, "%s", mbox->name);
-		if (IS_ERR(mbox->dev)) {
-			ret = PTR_ERR(mbox->dev);
-			goto err_out;
-		}
-
-		BLOCKING_INIT_NOTIFIER_HEAD(&mbox->notifier);
-	}
-	return 0;
-
-err_out:
-	while (i--)
-		device_unregister(mboxes[i]->dev);
-	return ret;
-}
-EXPORT_SYMBOL(omap_mbox_register);
-
-int omap_mbox_unregister(void)
-{
-	int i;
-
-	if (!mboxes)
-		return -EINVAL;
-
-	for (i = 0; mboxes[i]; i++)
-		device_unregister(mboxes[i]->dev);
-	mboxes = NULL;
-	return 0;
-}
-EXPORT_SYMBOL(omap_mbox_unregister);
-
-static int __init omap_mbox_init(void)
-{
-	int err;
-
-	err = class_register(&omap_mbox_class);
-	if (err)
-		return err;
-
-	/* kfifo size sanity check: alignment and minimal size */
-	mbox_kfifo_size = ALIGN(mbox_kfifo_size, sizeof(mbox_msg_t));
-	mbox_kfifo_size = max_t(unsigned int, mbox_kfifo_size,
-							sizeof(mbox_msg_t));
-
-	return 0;
-}
-subsys_initcall(omap_mbox_init);
-
-static void __exit omap_mbox_exit(void)
-{
-	class_unregister(&omap_mbox_class);
-}
-module_exit(omap_mbox_exit);
-
-MODULE_LICENSE("GPL v2");
-MODULE_DESCRIPTION("omap mailbox: interrupt driven messaging");
-MODULE_AUTHOR("Toshihiro Kobayashi");
-MODULE_AUTHOR("Hiroshi DOYU");
diff --git a/drivers/Kconfig b/drivers/Kconfig
index dbdefa3..7a4fb98 100644
--- a/drivers/Kconfig
+++ b/drivers/Kconfig
@@ -134,6 +134,8 @@ source "drivers/hwspinlock/Kconfig"
 
 source "drivers/clocksource/Kconfig"
 
+source "drivers/mailbox/Kconfig"
+
 source "drivers/iommu/Kconfig"
 
 source "drivers/remoteproc/Kconfig"
diff --git a/drivers/Makefile b/drivers/Makefile
index a16a8d0..78f2bf0 100644
--- a/drivers/Makefile
+++ b/drivers/Makefile
@@ -132,6 +132,7 @@ obj-y				+= clk/
 
 obj-$(CONFIG_HWSPINLOCK)	+= hwspinlock/
 obj-$(CONFIG_NFC)		+= nfc/
+obj-$(CONFIG_MAILBOX)		+= mailbox/
 obj-$(CONFIG_IOMMU_SUPPORT)	+= iommu/
 obj-$(CONFIG_REMOTEPROC)	+= remoteproc/
 obj-$(CONFIG_RPMSG)		+= rpmsg/
diff --git a/drivers/mailbox/Kconfig b/drivers/mailbox/Kconfig
new file mode 100644
index 0000000..937b887
--- /dev/null
+++ b/drivers/mailbox/Kconfig
@@ -0,0 +1,28 @@
+menuconfig MAILBOX
+	bool "Mailbox Hardware Support"
+	help
+	  Mailbox is a framework to control hardware communication between
+	  on-chip processors through queued messages and interrupt driven
+	  signals. Say Y if your platform supports hardware mailboxes.
+
+if MAILBOX
+
+config OMAP_MBOX_FWK
+	tristate "OMAP Mailbox framework support"
+	depends on ARCH_OMAP
+	help
+	  Mailbox implementation for OMAP family chips with hardware for
+	  interprocessor communication involving DSP, IVA1.0 and IVA2 in
+	  OMAP1/2/3; or IPU, IVA HD and DSP in OMAP4. Say Y here if you
+	  want to use OMAP Mailbox framework support.
+
+config OMAP_MBOX_KFIFO_SIZE
+	int "Mailbox kfifo default buffer size (bytes)"
+	depends on OMAP_MBOX_FWK
+	default 256
+	help
+	  Specify the default size of mailbox's kfifo buffers (bytes).
+	  This can also be changed at runtime (via the mbox_kfifo_size
+	  module parameter).
+
+endif
diff --git a/drivers/mailbox/Makefile b/drivers/mailbox/Makefile
new file mode 100644
index 0000000..1040ac5
--- /dev/null
+++ b/drivers/mailbox/Makefile
@@ -0,0 +1 @@
+obj-$(CONFIG_OMAP_MBOX_FWK) += mailbox.o
diff --git a/drivers/mailbox/mailbox.c b/drivers/mailbox/mailbox.c
new file mode 100644
index 0000000..cae8692
--- /dev/null
+++ b/drivers/mailbox/mailbox.c
@@ -0,0 +1,435 @@
+/*
+ * OMAP mailbox driver
+ *
+ * Copyright (C) 2006-2009 Nokia Corporation. All rights reserved.
+ *
+ * Contact: Hiroshi DOYU <Hiroshi.DOYU@nokia.com>
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * version 2 as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA
+ * 02110-1301 USA
+ *
+ */
+
+#include <linux/interrupt.h>
+#include <linux/spinlock.h>
+#include <linux/mutex.h>
+#include <linux/delay.h>
+#include <linux/slab.h>
+#include <linux/kfifo.h>
+#include <linux/err.h>
+#include <linux/notifier.h>
+#include <linux/module.h>
+
+#include <linux/platform_data/omap_mailbox.h>
+
+static struct omap_mbox **mboxes;
+
+static int mbox_configured;
+static DEFINE_MUTEX(mbox_configured_lock);
+
+static unsigned int mbox_kfifo_size = CONFIG_OMAP_MBOX_KFIFO_SIZE;
+module_param(mbox_kfifo_size, uint, S_IRUGO);
+MODULE_PARM_DESC(mbox_kfifo_size, "Size of omap's mailbox kfifo (bytes)");
+
+/* Mailbox FIFO handle functions */
+static inline mbox_msg_t mbox_fifo_read(struct omap_mbox *mbox)
+{
+	return mbox->ops->fifo_read(mbox);
+}
+static inline void mbox_fifo_write(struct omap_mbox *mbox, mbox_msg_t msg)
+{
+	mbox->ops->fifo_write(mbox, msg);
+}
+static inline int mbox_fifo_empty(struct omap_mbox *mbox)
+{
+	return mbox->ops->fifo_empty(mbox);
+}
+static inline int mbox_fifo_full(struct omap_mbox *mbox)
+{
+	return mbox->ops->fifo_full(mbox);
+}
+
+/* Mailbox IRQ handle functions */
+static inline void ack_mbox_irq(struct omap_mbox *mbox, omap_mbox_irq_t irq)
+{
+	if (mbox->ops->ack_irq)
+		mbox->ops->ack_irq(mbox, irq);
+}
+static inline int is_mbox_irq(struct omap_mbox *mbox, omap_mbox_irq_t irq)
+{
+	return mbox->ops->is_irq(mbox, irq);
+}
+
+/*
+ * message sender
+ */
+static int __mbox_poll_for_space(struct omap_mbox *mbox)
+{
+	int ret = 0, i = 1000;
+
+	while (mbox_fifo_full(mbox)) {
+		if (mbox->ops->type == OMAP_MBOX_TYPE2)
+			return -1;
+		if (--i == 0)
+			return -1;
+		udelay(1);
+	}
+	return ret;
+}
+
+int omap_mbox_msg_send(struct omap_mbox *mbox, mbox_msg_t msg)
+{
+	struct omap_mbox_queue *mq = mbox->txq;
+	int ret = 0, len;
+
+	spin_lock_bh(&mq->lock);
+
+	if (kfifo_avail(&mq->fifo) < sizeof(msg)) {
+		ret = -ENOMEM;
+		goto out;
+	}
+
+	if (kfifo_is_empty(&mq->fifo) && !__mbox_poll_for_space(mbox)) {
+		mbox_fifo_write(mbox, msg);
+		goto out;
+	}
+
+	len = kfifo_in(&mq->fifo, (unsigned char *)&msg, sizeof(msg));
+	WARN_ON(len != sizeof(msg));
+
+	tasklet_schedule(&mbox->txq->tasklet);
+
+out:
+	spin_unlock_bh(&mq->lock);
+	return ret;
+}
+EXPORT_SYMBOL(omap_mbox_msg_send);
+
+static void mbox_tx_tasklet(unsigned long tx_data)
+{
+	struct omap_mbox *mbox = (struct omap_mbox *)tx_data;
+	struct omap_mbox_queue *mq = mbox->txq;
+	mbox_msg_t msg;
+	int ret;
+
+	while (kfifo_len(&mq->fifo)) {
+		if (__mbox_poll_for_space(mbox)) {
+			omap_mbox_enable_irq(mbox, IRQ_TX);
+			break;
+		}
+
+		ret = kfifo_out(&mq->fifo, (unsigned char *)&msg,
+								sizeof(msg));
+		WARN_ON(ret != sizeof(msg));
+
+		mbox_fifo_write(mbox, msg);
+	}
+}
+
+/*
+ * Message receiver(workqueue)
+ */
+static void mbox_rx_work(struct work_struct *work)
+{
+	struct omap_mbox_queue *mq =
+			container_of(work, struct omap_mbox_queue, work);
+	mbox_msg_t msg;
+	int len;
+
+	while (kfifo_len(&mq->fifo) >= sizeof(msg)) {
+		len = kfifo_out(&mq->fifo, (unsigned char *)&msg, sizeof(msg));
+		WARN_ON(len != sizeof(msg));
+
+		blocking_notifier_call_chain(&mq->mbox->notifier, len,
+								(void *)msg);
+		spin_lock_irq(&mq->lock);
+		if (mq->full) {
+			mq->full = false;
+			omap_mbox_enable_irq(mq->mbox, IRQ_RX);
+		}
+		spin_unlock_irq(&mq->lock);
+	}
+}
+
+/*
+ * Mailbox interrupt handler
+ */
+static void __mbox_tx_interrupt(struct omap_mbox *mbox)
+{
+	omap_mbox_disable_irq(mbox, IRQ_TX);
+	ack_mbox_irq(mbox, IRQ_TX);
+	tasklet_schedule(&mbox->txq->tasklet);
+}
+
+static void __mbox_rx_interrupt(struct omap_mbox *mbox)
+{
+	struct omap_mbox_queue *mq = mbox->rxq;
+	mbox_msg_t msg;
+	int len;
+
+	while (!mbox_fifo_empty(mbox)) {
+		if (unlikely(kfifo_avail(&mq->fifo) < sizeof(msg))) {
+			omap_mbox_disable_irq(mbox, IRQ_RX);
+			mq->full = true;
+			goto nomem;
+		}
+
+		msg = mbox_fifo_read(mbox);
+
+		len = kfifo_in(&mq->fifo, (unsigned char *)&msg, sizeof(msg));
+		WARN_ON(len != sizeof(msg));
+
+		if (mbox->ops->type == OMAP_MBOX_TYPE1)
+			break;
+	}
+
+	/* no more messages in the fifo. clear IRQ source. */
+	ack_mbox_irq(mbox, IRQ_RX);
+nomem:
+	schedule_work(&mbox->rxq->work);
+}
+
+static irqreturn_t mbox_interrupt(int irq, void *p)
+{
+	struct omap_mbox *mbox = p;
+
+	if (is_mbox_irq(mbox, IRQ_TX))
+		__mbox_tx_interrupt(mbox);
+
+	if (is_mbox_irq(mbox, IRQ_RX))
+		__mbox_rx_interrupt(mbox);
+
+	return IRQ_HANDLED;
+}
+
+static struct omap_mbox_queue *mbox_queue_alloc(struct omap_mbox *mbox,
+					void (*work) (struct work_struct *),
+					void (*tasklet)(unsigned long))
+{
+	struct omap_mbox_queue *mq;
+
+	mq = kzalloc(sizeof(struct omap_mbox_queue), GFP_KERNEL);
+	if (!mq)
+		return NULL;
+
+	spin_lock_init(&mq->lock);
+
+	if (kfifo_alloc(&mq->fifo, mbox_kfifo_size, GFP_KERNEL))
+		goto error;
+
+	if (work)
+		INIT_WORK(&mq->work, work);
+
+	if (tasklet)
+		tasklet_init(&mq->tasklet, tasklet, (unsigned long)mbox);
+	return mq;
+error:
+	kfree(mq);
+	return NULL;
+}
+
+static void mbox_queue_free(struct omap_mbox_queue *q)
+{
+	kfifo_free(&q->fifo);
+	kfree(q);
+}
+
+static int omap_mbox_startup(struct omap_mbox *mbox)
+{
+	int ret = 0;
+	struct omap_mbox_queue *mq;
+
+	mutex_lock(&mbox_configured_lock);
+	if (!mbox_configured++) {
+		if (likely(mbox->ops->startup)) {
+			ret = mbox->ops->startup(mbox);
+			if (unlikely(ret))
+				goto fail_startup;
+		} else
+			goto fail_startup;
+	}
+
+	if (!mbox->use_count++) {
+		ret = request_irq(mbox->irq, mbox_interrupt, IRQF_SHARED,
+							mbox->name, mbox);
+		if (unlikely(ret)) {
+			pr_err("failed to register mailbox interrupt:%d\n",
+									ret);
+			goto fail_request_irq;
+		}
+		mq = mbox_queue_alloc(mbox, NULL, mbox_tx_tasklet);
+		if (!mq) {
+			ret = -ENOMEM;
+			goto fail_alloc_txq;
+		}
+		mbox->txq = mq;
+
+		mq = mbox_queue_alloc(mbox, mbox_rx_work, NULL);
+		if (!mq) {
+			ret = -ENOMEM;
+			goto fail_alloc_rxq;
+		}
+		mbox->rxq = mq;
+		mq->mbox = mbox;
+
+		omap_mbox_enable_irq(mbox, IRQ_RX);
+	}
+	mutex_unlock(&mbox_configured_lock);
+	return 0;
+
+fail_alloc_rxq:
+	mbox_queue_free(mbox->txq);
+fail_alloc_txq:
+	free_irq(mbox->irq, mbox);
+fail_request_irq:
+	if (mbox->ops->shutdown)
+		mbox->ops->shutdown(mbox);
+	mbox->use_count--;
+fail_startup:
+	mbox_configured--;
+	mutex_unlock(&mbox_configured_lock);
+	return ret;
+}
+
+static void omap_mbox_fini(struct omap_mbox *mbox)
+{
+	mutex_lock(&mbox_configured_lock);
+
+	if (!--mbox->use_count) {
+		omap_mbox_disable_irq(mbox, IRQ_RX);
+		free_irq(mbox->irq, mbox);
+		tasklet_kill(&mbox->txq->tasklet);
+		flush_work(&mbox->rxq->work);
+		mbox_queue_free(mbox->txq);
+		mbox_queue_free(mbox->rxq);
+	}
+
+	if (likely(mbox->ops->shutdown)) {
+		if (!--mbox_configured)
+			mbox->ops->shutdown(mbox);
+	}
+
+	mutex_unlock(&mbox_configured_lock);
+}
+
+struct omap_mbox *omap_mbox_get(const char *name, struct notifier_block *nb)
+{
+	struct omap_mbox *_mbox, *mbox = NULL;
+	int i, ret;
+
+	if (!mboxes)
+		return ERR_PTR(-EINVAL);
+
+	for (i = 0; (_mbox = mboxes[i]); i++) {
+		if (!strcmp(_mbox->name, name)) {
+			mbox = _mbox;
+			break;
+		}
+	}
+
+	if (!mbox)
+		return ERR_PTR(-ENOENT);
+
+	if (nb)
+		blocking_notifier_chain_register(&mbox->notifier, nb);
+
+	ret = omap_mbox_startup(mbox);
+	if (ret) {
+		blocking_notifier_chain_unregister(&mbox->notifier, nb);
+		return ERR_PTR(-ENODEV);
+	}
+
+	return mbox;
+}
+EXPORT_SYMBOL(omap_mbox_get);
+
+void omap_mbox_put(struct omap_mbox *mbox, struct notifier_block *nb)
+{
+	blocking_notifier_chain_unregister(&mbox->notifier, nb);
+	omap_mbox_fini(mbox);
+}
+EXPORT_SYMBOL(omap_mbox_put);
+
+static struct class omap_mbox_class = { .name = "mbox", };
+
+int omap_mbox_register(struct device *parent, struct omap_mbox **list)
+{
+	int ret;
+	int i;
+
+	mboxes = list;
+	if (!mboxes)
+		return -EINVAL;
+
+	for (i = 0; mboxes[i]; i++) {
+		struct omap_mbox *mbox = mboxes[i];
+		mbox->dev = device_create(&omap_mbox_class,
+				parent, 0, mbox, "%s", mbox->name);
+		if (IS_ERR(mbox->dev)) {
+			ret = PTR_ERR(mbox->dev);
+			goto err_out;
+		}
+
+		BLOCKING_INIT_NOTIFIER_HEAD(&mbox->notifier);
+	}
+	return 0;
+
+err_out:
+	while (i--)
+		device_unregister(mboxes[i]->dev);
+	return ret;
+}
+EXPORT_SYMBOL(omap_mbox_register);
+
+int omap_mbox_unregister(void)
+{
+	int i;
+
+	if (!mboxes)
+		return -EINVAL;
+
+	for (i = 0; mboxes[i]; i++)
+		device_unregister(mboxes[i]->dev);
+	mboxes = NULL;
+	return 0;
+}
+EXPORT_SYMBOL(omap_mbox_unregister);
+
+static int __init omap_mbox_init(void)
+{
+	int err;
+
+	err = class_register(&omap_mbox_class);
+	if (err)
+		return err;
+
+	/* kfifo size sanity check: alignment and minimal size */
+	mbox_kfifo_size = ALIGN(mbox_kfifo_size, sizeof(mbox_msg_t));
+	mbox_kfifo_size = max_t(unsigned int, mbox_kfifo_size,
+							sizeof(mbox_msg_t));
+
+	return 0;
+}
+subsys_initcall(omap_mbox_init);
+
+static void __exit omap_mbox_exit(void)
+{
+	class_unregister(&omap_mbox_class);
+}
+module_exit(omap_mbox_exit);
+
+MODULE_LICENSE("GPL v2");
+MODULE_DESCRIPTION("omap mailbox: interrupt driven messaging");
+MODULE_AUTHOR("Toshihiro Kobayashi");
+MODULE_AUTHOR("Hiroshi DOYU");
-- 
1.7.9.5