diff mbox series

[1/4] ARM/omap1: switch to use dma_direct_set_offset for lbus DMA offsets

Message ID 20200917173229.3311382-2-hch@lst.de
State New
Headers show
Series [1/4] ARM/omap1: switch to use dma_direct_set_offset for lbus DMA offsets | expand

Commit Message

Christoph Hellwig Sept. 17, 2020, 5:32 p.m. UTC
Switch the omap1510 platform ohci device to use dma_direct_set_offset
to set the DMA offset instead of using direct hooks into the DMA
mapping code and remove the now unused hooks.

Signed-off-by: Christoph Hellwig <hch@lst.de>
---
 arch/arm/include/asm/dma-direct.h         | 18 -------------
 arch/arm/mach-omap1/include/mach/memory.h | 31 -----------------------
 arch/arm/mach-omap1/usb.c                 | 22 ++++++++++++++++
 3 files changed, 22 insertions(+), 49 deletions(-)

Comments

Tony Lindgren Sept. 18, 2020, 5:49 a.m. UTC | #1
* Christoph Hellwig <hch@lst.de> [200917 17:37]:
> Switch the omap1510 platform ohci device to use dma_direct_set_offset

> to set the DMA offset instead of using direct hooks into the DMA

> mapping code and remove the now unused hooks.


Looks nice to me :) I still can't test this probably for few more weeks
though but hopefully Aaro or Janusz (Added to Cc) can test it.

Regards,

Tony

> Signed-off-by: Christoph Hellwig <hch@lst.de>

> ---

>  arch/arm/include/asm/dma-direct.h         | 18 -------------

>  arch/arm/mach-omap1/include/mach/memory.h | 31 -----------------------

>  arch/arm/mach-omap1/usb.c                 | 22 ++++++++++++++++

>  3 files changed, 22 insertions(+), 49 deletions(-)

> 

> diff --git a/arch/arm/include/asm/dma-direct.h b/arch/arm/include/asm/dma-direct.h

> index 436544aeb83405..77fcb7ee5ec907 100644

> --- a/arch/arm/include/asm/dma-direct.h

> +++ b/arch/arm/include/asm/dma-direct.h

> @@ -9,7 +9,6 @@

>   * functions used internally by the DMA-mapping API to provide DMA

>   * addresses. They must not be used by drivers.

>   */

> -#ifndef __arch_pfn_to_dma

>  static inline dma_addr_t pfn_to_dma(struct device *dev, unsigned long pfn)

>  {

>  	if (dev && dev->dma_range_map)

> @@ -34,23 +33,6 @@ static inline dma_addr_t virt_to_dma(struct device *dev, void *addr)

>  	return (dma_addr_t)__virt_to_bus((unsigned long)(addr));

>  }

>  

> -#else

> -static inline dma_addr_t pfn_to_dma(struct device *dev, unsigned long pfn)

> -{

> -	return __arch_pfn_to_dma(dev, pfn);

> -}

> -

> -static inline unsigned long dma_to_pfn(struct device *dev, dma_addr_t addr)

> -{

> -	return __arch_dma_to_pfn(dev, addr);

> -}

> -

> -static inline dma_addr_t virt_to_dma(struct device *dev, void *addr)

> -{

> -	return __arch_virt_to_dma(dev, addr);

> -}

> -#endif

> -

>  static inline dma_addr_t phys_to_dma(struct device *dev, phys_addr_t paddr)

>  {

>  	unsigned int offset = paddr & ~PAGE_MASK;

> diff --git a/arch/arm/mach-omap1/include/mach/memory.h b/arch/arm/mach-omap1/include/mach/memory.h

> index 1142560e0078f5..36bc0000cb6ab8 100644

> --- a/arch/arm/mach-omap1/include/mach/memory.h

> +++ b/arch/arm/mach-omap1/include/mach/memory.h

> @@ -14,42 +14,11 @@

>   * OMAP-1510 bus address is translated into a Local Bus address if the

>   * OMAP bus type is lbus. We do the address translation based on the

>   * device overriding the defaults used in the dma-mapping API.

> - * Note that the is_lbus_device() test is not very efficient on 1510

> - * because of the strncmp().

>   */

> -#if defined(CONFIG_ARCH_OMAP15XX) && !defined(__ASSEMBLER__)

>  

>  /*

>   * OMAP-1510 Local Bus address offset

>   */

>  #define OMAP1510_LB_OFFSET	UL(0x30000000)

>  

> -#define virt_to_lbus(x)		((x) - PAGE_OFFSET + OMAP1510_LB_OFFSET)

> -#define lbus_to_virt(x)		((x) - OMAP1510_LB_OFFSET + PAGE_OFFSET)

> -#define is_lbus_device(dev)	(cpu_is_omap15xx() && dev && (strncmp(dev_name(dev), "ohci", 4) == 0))

> -

> -#define __arch_pfn_to_dma(dev, pfn)	\

> -	({ dma_addr_t __dma = __pfn_to_phys(pfn); \

> -	   if (is_lbus_device(dev)) \

> -		__dma = __dma - PHYS_OFFSET + OMAP1510_LB_OFFSET; \

> -	   __dma; })

> -

> -#define __arch_dma_to_pfn(dev, addr)	\

> -	({ dma_addr_t __dma = addr;				\

> -	   if (is_lbus_device(dev))				\

> -		__dma += PHYS_OFFSET - OMAP1510_LB_OFFSET;	\

> -	   __phys_to_pfn(__dma);				\

> -	})

> -

> -#define __arch_dma_to_virt(dev, addr)	({ (void *) (is_lbus_device(dev) ? \

> -						lbus_to_virt(addr) : \

> -						__phys_to_virt(addr)); })

> -

> -#define __arch_virt_to_dma(dev, addr)	({ unsigned long __addr = (unsigned long)(addr); \

> -					   (dma_addr_t) (is_lbus_device(dev) ? \

> -						virt_to_lbus(__addr) : \

> -						__virt_to_phys(__addr)); })

> -

> -#endif	/* CONFIG_ARCH_OMAP15XX */

> -

>  #endif

> diff --git a/arch/arm/mach-omap1/usb.c b/arch/arm/mach-omap1/usb.c

> index d8e9bbda8f7bdd..ba8566204ea9f4 100644

> --- a/arch/arm/mach-omap1/usb.c

> +++ b/arch/arm/mach-omap1/usb.c

> @@ -9,6 +9,7 @@

>  #include <linux/kernel.h>

>  #include <linux/init.h>

>  #include <linux/platform_device.h>

> +#include <linux/dma-mapping.h>

>  #include <linux/io.h>

>  

>  #include <asm/irq.h>

> @@ -542,6 +543,25 @@ static u32 __init omap1_usb2_init(unsigned nwires, unsigned alt_pingroup)

>  /* ULPD_APLL_CTRL */

>  #define APLL_NDPLL_SWITCH	(1 << 0)

>  

> +static int omap_1510_usb_ohci_notifier(struct notifier_block *nb,

> +		unsigned long event, void *data)

> +{

> +	struct device *dev = data;

> +

> +	if (event != BUS_NOTIFY_ADD_DEVICE)

> +		return NOTIFY_DONE;

> +

> +	if (strncmp(dev_name(dev), "ohci", 4) == 0 &&

> +	    dma_direct_set_offset(dev, PHYS_OFFSET, OMAP1510_LB_OFFSET,

> +			(u64)-1))

> +		WARN_ONCE(1, "failed to set DMA offset\n");

> +	return NOTIFY_OK;

> +}

> +

> +static struct notifier_block omap_1510_usb_ohci_nb = {

> +	.notifier_call		= omap_1510_usb_ohci_notifier,

> +};

> +

>  static void __init omap_1510_usb_init(struct omap_usb_config *config)

>  {

>  	unsigned int val;

> @@ -600,6 +620,8 @@ static void __init omap_1510_usb_init(struct omap_usb_config *config)

>  	if (config->register_host) {

>  		int status;

>  

> +		bus_register_notifier(&platform_bus_type,

> +				      &omap_1510_usb_ohci_nb);

>  		ohci_device.dev.platform_data = config;

>  		status = platform_device_register(&ohci_device);

>  		if (status)

> -- 

> 2.28.0

>
Janusz Krzysztofik Sept. 19, 2020, 10:29 p.m. UTC | #2
Hi Tony,

On Friday, September 18, 2020 7:49:33 A.M. CEST Tony Lindgren wrote:
> * Christoph Hellwig <hch@lst.de> [200917 17:37]:

> > Switch the omap1510 platform ohci device to use dma_direct_set_offset

> > to set the DMA offset instead of using direct hooks into the DMA

> > mapping code and remove the now unused hooks.

> 

> Looks nice to me :) I still can't test this probably for few more weeks

> though but hopefully Aaro or Janusz (Added to Cc) can test it.


Works for me on Amstrad Delta (tested with a USB ethernet adapter).

Tested-by: Janusz Krzysztofik <jmkrzyszt@gmail.com>


Thanks,
Janusz

> 

> Regards,

> 

> Tony

> 

> > Signed-off-by: Christoph Hellwig <hch@lst.de>

> > ---

> >  arch/arm/include/asm/dma-direct.h         | 18 -------------

> >  arch/arm/mach-omap1/include/mach/memory.h | 31 -----------------------

> >  arch/arm/mach-omap1/usb.c                 | 22 ++++++++++++++++

> >  3 files changed, 22 insertions(+), 49 deletions(-)

> > 

> > diff --git a/arch/arm/include/asm/dma-direct.h b/arch/arm/include/asm/dma-direct.h

> > index 436544aeb83405..77fcb7ee5ec907 100644

> > --- a/arch/arm/include/asm/dma-direct.h

> > +++ b/arch/arm/include/asm/dma-direct.h

> > @@ -9,7 +9,6 @@

> >   * functions used internally by the DMA-mapping API to provide DMA

> >   * addresses. They must not be used by drivers.

> >   */

> > -#ifndef __arch_pfn_to_dma

> >  static inline dma_addr_t pfn_to_dma(struct device *dev, unsigned long pfn)

> >  {

> >  	if (dev && dev->dma_range_map)

> > @@ -34,23 +33,6 @@ static inline dma_addr_t virt_to_dma(struct device *dev, void *addr)

> >  	return (dma_addr_t)__virt_to_bus((unsigned long)(addr));

> >  }

> >  

> > -#else

> > -static inline dma_addr_t pfn_to_dma(struct device *dev, unsigned long pfn)

> > -{

> > -	return __arch_pfn_to_dma(dev, pfn);

> > -}

> > -

> > -static inline unsigned long dma_to_pfn(struct device *dev, dma_addr_t addr)

> > -{

> > -	return __arch_dma_to_pfn(dev, addr);

> > -}

> > -

> > -static inline dma_addr_t virt_to_dma(struct device *dev, void *addr)

> > -{

> > -	return __arch_virt_to_dma(dev, addr);

> > -}

> > -#endif

> > -

> >  static inline dma_addr_t phys_to_dma(struct device *dev, phys_addr_t paddr)

> >  {

> >  	unsigned int offset = paddr & ~PAGE_MASK;

> > diff --git a/arch/arm/mach-omap1/include/mach/memory.h b/arch/arm/mach-omap1/include/mach/memory.h

> > index 1142560e0078f5..36bc0000cb6ab8 100644

> > --- a/arch/arm/mach-omap1/include/mach/memory.h

> > +++ b/arch/arm/mach-omap1/include/mach/memory.h

> > @@ -14,42 +14,11 @@

> >   * OMAP-1510 bus address is translated into a Local Bus address if the

> >   * OMAP bus type is lbus. We do the address translation based on the

> >   * device overriding the defaults used in the dma-mapping API.

> > - * Note that the is_lbus_device() test is not very efficient on 1510

> > - * because of the strncmp().

> >   */

> > -#if defined(CONFIG_ARCH_OMAP15XX) && !defined(__ASSEMBLER__)

> >  

> >  /*

> >   * OMAP-1510 Local Bus address offset

> >   */

> >  #define OMAP1510_LB_OFFSET	UL(0x30000000)

> >  

> > -#define virt_to_lbus(x)		((x) - PAGE_OFFSET + OMAP1510_LB_OFFSET)

> > -#define lbus_to_virt(x)		((x) - OMAP1510_LB_OFFSET + PAGE_OFFSET)

> > -#define is_lbus_device(dev)	(cpu_is_omap15xx() && dev && (strncmp(dev_name(dev), "ohci", 4) == 0))

> > -

> > -#define __arch_pfn_to_dma(dev, pfn)	\

> > -	({ dma_addr_t __dma = __pfn_to_phys(pfn); \

> > -	   if (is_lbus_device(dev)) \

> > -		__dma = __dma - PHYS_OFFSET + OMAP1510_LB_OFFSET; \

> > -	   __dma; })

> > -

> > -#define __arch_dma_to_pfn(dev, addr)	\

> > -	({ dma_addr_t __dma = addr;				\

> > -	   if (is_lbus_device(dev))				\

> > -		__dma += PHYS_OFFSET - OMAP1510_LB_OFFSET;	\

> > -	   __phys_to_pfn(__dma);				\

> > -	})

> > -

> > -#define __arch_dma_to_virt(dev, addr)	({ (void *) (is_lbus_device(dev) ? \

> > -						lbus_to_virt(addr) : \

> > -						__phys_to_virt(addr)); })

> > -

> > -#define __arch_virt_to_dma(dev, addr)	({ unsigned long __addr = (unsigned long)(addr); \

> > -					   (dma_addr_t) (is_lbus_device(dev) ? \

> > -						virt_to_lbus(__addr) : \

> > -						__virt_to_phys(__addr)); })

> > -

> > -#endif	/* CONFIG_ARCH_OMAP15XX */

> > -

> >  #endif

> > diff --git a/arch/arm/mach-omap1/usb.c b/arch/arm/mach-omap1/usb.c

> > index d8e9bbda8f7bdd..ba8566204ea9f4 100644

> > --- a/arch/arm/mach-omap1/usb.c

> > +++ b/arch/arm/mach-omap1/usb.c

> > @@ -9,6 +9,7 @@

> >  #include <linux/kernel.h>

> >  #include <linux/init.h>

> >  #include <linux/platform_device.h>

> > +#include <linux/dma-mapping.h>

> >  #include <linux/io.h>

> >  

> >  #include <asm/irq.h>

> > @@ -542,6 +543,25 @@ static u32 __init omap1_usb2_init(unsigned nwires, unsigned alt_pingroup)

> >  /* ULPD_APLL_CTRL */

> >  #define APLL_NDPLL_SWITCH	(1 << 0)

> >  

> > +static int omap_1510_usb_ohci_notifier(struct notifier_block *nb,

> > +		unsigned long event, void *data)

> > +{

> > +	struct device *dev = data;

> > +

> > +	if (event != BUS_NOTIFY_ADD_DEVICE)

> > +		return NOTIFY_DONE;

> > +

> > +	if (strncmp(dev_name(dev), "ohci", 4) == 0 &&

> > +	    dma_direct_set_offset(dev, PHYS_OFFSET, OMAP1510_LB_OFFSET,

> > +			(u64)-1))

> > +		WARN_ONCE(1, "failed to set DMA offset\n");

> > +	return NOTIFY_OK;

> > +}

> > +

> > +static struct notifier_block omap_1510_usb_ohci_nb = {

> > +	.notifier_call		= omap_1510_usb_ohci_notifier,

> > +};

> > +

> >  static void __init omap_1510_usb_init(struct omap_usb_config *config)

> >  {

> >  	unsigned int val;

> > @@ -600,6 +620,8 @@ static void __init omap_1510_usb_init(struct omap_usb_config *config)

> >  	if (config->register_host) {

> >  		int status;

> >  

> > +		bus_register_notifier(&platform_bus_type,

> > +				      &omap_1510_usb_ohci_nb);

> >  		ohci_device.dev.platform_data = config;

> >  		status = platform_device_register(&ohci_device);

> >  		if (status)

>
Tony Lindgren Sept. 21, 2020, 6:44 a.m. UTC | #3
* Janusz Krzysztofik <jmkrzyszt@gmail.com> [200919 22:29]:
> Hi Tony,
> 
> On Friday, September 18, 2020 7:49:33 A.M. CEST Tony Lindgren wrote:
> > * Christoph Hellwig <hch@lst.de> [200917 17:37]:
> > > Switch the omap1510 platform ohci device to use dma_direct_set_offset
> > > to set the DMA offset instead of using direct hooks into the DMA
> > > mapping code and remove the now unused hooks.
> > 
> > Looks nice to me :) I still can't test this probably for few more weeks
> > though but hopefully Aaro or Janusz (Added to Cc) can test it.
> 
> Works for me on Amstrad Delta (tested with a USB ethernet adapter).
> 
> Tested-by: Janusz Krzysztofik <jmkrzyszt@gmail.com>

Great, good to hear! And thanks for testing it.

Christoph, feel free to queue this along with the other patches:

Acked-by: Tony Lindgren <tony@atomide.com>

Or let me know if you want me to pick it up.

Regards,

Tony
Christoph Hellwig Sept. 21, 2020, 6:47 a.m. UTC | #4
On Mon, Sep 21, 2020 at 09:44:18AM +0300, Tony Lindgren wrote:
> * Janusz Krzysztofik <jmkrzyszt@gmail.com> [200919 22:29]:
> > Hi Tony,
> > 
> > On Friday, September 18, 2020 7:49:33 A.M. CEST Tony Lindgren wrote:
> > > * Christoph Hellwig <hch@lst.de> [200917 17:37]:
> > > > Switch the omap1510 platform ohci device to use dma_direct_set_offset
> > > > to set the DMA offset instead of using direct hooks into the DMA
> > > > mapping code and remove the now unused hooks.
> > > 
> > > Looks nice to me :) I still can't test this probably for few more weeks
> > > though but hopefully Aaro or Janusz (Added to Cc) can test it.
> > 
> > Works for me on Amstrad Delta (tested with a USB ethernet adapter).
> > 
> > Tested-by: Janusz Krzysztofik <jmkrzyszt@gmail.com>
> 
> Great, good to hear! And thanks for testing it.
> 
> Christoph, feel free to queue this along with the other patches:
> 
> Acked-by: Tony Lindgren <tony@atomide.com>
> 
> Or let me know if you want me to pick it up.

I'd prefer to pick it up through the dma-mapping tree, but preferably
I'd pick the whole series up once Russell has tested footwinder.
Russell King (Oracle) Sept. 23, 2020, 10:05 a.m. UTC | #5
On Mon, Sep 21, 2020 at 08:47:23AM +0200, Christoph Hellwig wrote:
> On Mon, Sep 21, 2020 at 09:44:18AM +0300, Tony Lindgren wrote:
> > * Janusz Krzysztofik <jmkrzyszt@gmail.com> [200919 22:29]:
> > > Hi Tony,
> > > 
> > > On Friday, September 18, 2020 7:49:33 A.M. CEST Tony Lindgren wrote:
> > > > * Christoph Hellwig <hch@lst.de> [200917 17:37]:
> > > > > Switch the omap1510 platform ohci device to use dma_direct_set_offset
> > > > > to set the DMA offset instead of using direct hooks into the DMA
> > > > > mapping code and remove the now unused hooks.
> > > > 
> > > > Looks nice to me :) I still can't test this probably for few more weeks
> > > > though but hopefully Aaro or Janusz (Added to Cc) can test it.
> > > 
> > > Works for me on Amstrad Delta (tested with a USB ethernet adapter).
> > > 
> > > Tested-by: Janusz Krzysztofik <jmkrzyszt@gmail.com>
> > 
> > Great, good to hear! And thanks for testing it.
> > 
> > Christoph, feel free to queue this along with the other patches:
> > 
> > Acked-by: Tony Lindgren <tony@atomide.com>
> > 
> > Or let me know if you want me to pick it up.
> 
> I'd prefer to pick it up through the dma-mapping tree, but preferably
> I'd pick the whole series up once Russell has tested footwinder.

I don't think that's going to happen very soon... seems way too much
effort to pull down the appropriate tree to build and test.  Sorry.
diff mbox series

Patch

diff --git a/arch/arm/include/asm/dma-direct.h b/arch/arm/include/asm/dma-direct.h
index 436544aeb83405..77fcb7ee5ec907 100644
--- a/arch/arm/include/asm/dma-direct.h
+++ b/arch/arm/include/asm/dma-direct.h
@@ -9,7 +9,6 @@ 
  * functions used internally by the DMA-mapping API to provide DMA
  * addresses. They must not be used by drivers.
  */
-#ifndef __arch_pfn_to_dma
 static inline dma_addr_t pfn_to_dma(struct device *dev, unsigned long pfn)
 {
 	if (dev && dev->dma_range_map)
@@ -34,23 +33,6 @@  static inline dma_addr_t virt_to_dma(struct device *dev, void *addr)
 	return (dma_addr_t)__virt_to_bus((unsigned long)(addr));
 }
 
-#else
-static inline dma_addr_t pfn_to_dma(struct device *dev, unsigned long pfn)
-{
-	return __arch_pfn_to_dma(dev, pfn);
-}
-
-static inline unsigned long dma_to_pfn(struct device *dev, dma_addr_t addr)
-{
-	return __arch_dma_to_pfn(dev, addr);
-}
-
-static inline dma_addr_t virt_to_dma(struct device *dev, void *addr)
-{
-	return __arch_virt_to_dma(dev, addr);
-}
-#endif
-
 static inline dma_addr_t phys_to_dma(struct device *dev, phys_addr_t paddr)
 {
 	unsigned int offset = paddr & ~PAGE_MASK;
diff --git a/arch/arm/mach-omap1/include/mach/memory.h b/arch/arm/mach-omap1/include/mach/memory.h
index 1142560e0078f5..36bc0000cb6ab8 100644
--- a/arch/arm/mach-omap1/include/mach/memory.h
+++ b/arch/arm/mach-omap1/include/mach/memory.h
@@ -14,42 +14,11 @@ 
  * OMAP-1510 bus address is translated into a Local Bus address if the
  * OMAP bus type is lbus. We do the address translation based on the
  * device overriding the defaults used in the dma-mapping API.
- * Note that the is_lbus_device() test is not very efficient on 1510
- * because of the strncmp().
  */
-#if defined(CONFIG_ARCH_OMAP15XX) && !defined(__ASSEMBLER__)
 
 /*
  * OMAP-1510 Local Bus address offset
  */
 #define OMAP1510_LB_OFFSET	UL(0x30000000)
 
-#define virt_to_lbus(x)		((x) - PAGE_OFFSET + OMAP1510_LB_OFFSET)
-#define lbus_to_virt(x)		((x) - OMAP1510_LB_OFFSET + PAGE_OFFSET)
-#define is_lbus_device(dev)	(cpu_is_omap15xx() && dev && (strncmp(dev_name(dev), "ohci", 4) == 0))
-
-#define __arch_pfn_to_dma(dev, pfn)	\
-	({ dma_addr_t __dma = __pfn_to_phys(pfn); \
-	   if (is_lbus_device(dev)) \
-		__dma = __dma - PHYS_OFFSET + OMAP1510_LB_OFFSET; \
-	   __dma; })
-
-#define __arch_dma_to_pfn(dev, addr)	\
-	({ dma_addr_t __dma = addr;				\
-	   if (is_lbus_device(dev))				\
-		__dma += PHYS_OFFSET - OMAP1510_LB_OFFSET;	\
-	   __phys_to_pfn(__dma);				\
-	})
-
-#define __arch_dma_to_virt(dev, addr)	({ (void *) (is_lbus_device(dev) ? \
-						lbus_to_virt(addr) : \
-						__phys_to_virt(addr)); })
-
-#define __arch_virt_to_dma(dev, addr)	({ unsigned long __addr = (unsigned long)(addr); \
-					   (dma_addr_t) (is_lbus_device(dev) ? \
-						virt_to_lbus(__addr) : \
-						__virt_to_phys(__addr)); })
-
-#endif	/* CONFIG_ARCH_OMAP15XX */
-
 #endif
diff --git a/arch/arm/mach-omap1/usb.c b/arch/arm/mach-omap1/usb.c
index d8e9bbda8f7bdd..ba8566204ea9f4 100644
--- a/arch/arm/mach-omap1/usb.c
+++ b/arch/arm/mach-omap1/usb.c
@@ -9,6 +9,7 @@ 
 #include <linux/kernel.h>
 #include <linux/init.h>
 #include <linux/platform_device.h>
+#include <linux/dma-mapping.h>
 #include <linux/io.h>
 
 #include <asm/irq.h>
@@ -542,6 +543,25 @@  static u32 __init omap1_usb2_init(unsigned nwires, unsigned alt_pingroup)
 /* ULPD_APLL_CTRL */
 #define APLL_NDPLL_SWITCH	(1 << 0)
 
+static int omap_1510_usb_ohci_notifier(struct notifier_block *nb,
+		unsigned long event, void *data)
+{
+	struct device *dev = data;
+
+	if (event != BUS_NOTIFY_ADD_DEVICE)
+		return NOTIFY_DONE;
+
+	if (strncmp(dev_name(dev), "ohci", 4) == 0 &&
+	    dma_direct_set_offset(dev, PHYS_OFFSET, OMAP1510_LB_OFFSET,
+			(u64)-1))
+		WARN_ONCE(1, "failed to set DMA offset\n");
+	return NOTIFY_OK;
+}
+
+static struct notifier_block omap_1510_usb_ohci_nb = {
+	.notifier_call		= omap_1510_usb_ohci_notifier,
+};
+
 static void __init omap_1510_usb_init(struct omap_usb_config *config)
 {
 	unsigned int val;
@@ -600,6 +620,8 @@  static void __init omap_1510_usb_init(struct omap_usb_config *config)
 	if (config->register_host) {
 		int status;
 
+		bus_register_notifier(&platform_bus_type,
+				      &omap_1510_usb_ohci_nb);
 		ohci_device.dev.platform_data = config;
 		status = platform_device_register(&ohci_device);
 		if (status)