diff mbox series

of: Make of framebuffer devices unique

Message ID	20230117165804.18036-1-msuchanek@suse.de
State	New
Headers	Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 2620:137:e000::1:20 as permitted sender) client-ip=2620:137:e000::1:20; From: Michal Suchanek <msuchanek@suse.de> Cc: Michal Suchanek <msuchanek@suse.de>, Rob Herring <robh+dt@kernel.org>, Frank Rowand <frowand.list@gmail.com>, Thomas Zimmermann <tzimmermann@suse.de>, Javier Martinez Canillas <javierm@redhat.com>, devicetree@vger.kernel.org (open list:OPEN FIRMWARE AND FLATTENED DEVICE TREE), linux-kernel@vger.kernel.org (open list), linuxppc-dev@lists.ozlabs.org, "Erhard F ." <erhard_f@mailbox.org> Subject: [PATCH] of: Make of framebuffer devices unique Date: Tue, 17 Jan 2023 17:58:04 +0100 Message-Id: <20230117165804.18036-1-msuchanek@suse.de> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit To: unlisted-recipients:; (no To-header on input) Precedence: bulk
Series	of: Make of framebuffer devices unique \| of: Make of framebuffer devices unique

Commit Message

Michal Suchánek Jan. 17, 2023, 4:58 p.m. UTC

  Since Linux 5.19 this error is observed:

sysfs: cannot create duplicate filename '/devices/platform/of-display'

This is because multiple devices with the same name 'of-display' are
created on the same bus.

Update the code to create numbered device names for the non-boot
disaplay.

cc: linuxppc-dev@lists.ozlabs.org
References: https://bugzilla.kernel.org/show_bug.cgi?id=216095
Fixes: 52b1b46c39ae ("of: Create platform devices for OF framebuffers")
Reported-by: Erhard F. <erhard_f@mailbox.org>
Suggested-by: Thomas Zimmermann <tzimmermann@suse.de>
Signed-off-by: Michal Suchanek <msuchanek@suse.de>
---
 drivers/of/platform.c | 8 +++++++-
 1 file changed, 7 insertions(+), 1 deletion(-)

Comments

Rob Herring Jan. 18, 2023, 4:24 p.m. UTC | #1

On Tue, 17 Jan 2023 17:58:04 +0100, Michal Suchanek wrote:
> Since Linux 5.19 this error is observed:
> 
> sysfs: cannot create duplicate filename '/devices/platform/of-display'
> 
> This is because multiple devices with the same name 'of-display' are
> created on the same bus.
> 
> Update the code to create numbered device names for the non-boot
> disaplay.
> 
> cc: linuxppc-dev@lists.ozlabs.org
> References: https://bugzilla.kernel.org/show_bug.cgi?id=216095
> Fixes: 52b1b46c39ae ("of: Create platform devices for OF framebuffers")
> Reported-by: Erhard F. <erhard_f@mailbox.org>
> Suggested-by: Thomas Zimmermann <tzimmermann@suse.de>
> Signed-off-by: Michal Suchanek <msuchanek@suse.de>
> ---
>  drivers/of/platform.c | 8 +++++++-
>  1 file changed, 7 insertions(+), 1 deletion(-)
> 

Applied, thanks!

Erhard Furtner Jan. 18, 2023, 8:13 p.m. UTC | #2

On Tue, 17 Jan 2023 17:58:04 +0100
Michal Suchanek <msuchanek@suse.de> wrote:

> Since Linux 5.19 this error is observed:
> 
> sysfs: cannot create duplicate filename '/devices/platform/of-display'
> 
> This is because multiple devices with the same name 'of-display' are
> created on the same bus.
> 
> Update the code to create numbered device names for the non-boot
> disaplay.
> 
> cc: linuxppc-dev@lists.ozlabs.org
> References: https://bugzilla.kernel.org/show_bug.cgi?id=216095
> Fixes: 52b1b46c39ae ("of: Create platform devices for OF framebuffers")
> Reported-by: Erhard F. <erhard_f@mailbox.org>
> Suggested-by: Thomas Zimmermann <tzimmermann@suse.de>
> Signed-off-by: Michal Suchanek <msuchanek@suse.de>
> ---
>  drivers/of/platform.c | 8 +++++++-
>  1 file changed, 7 insertions(+), 1 deletion(-)
> 
> diff --git a/drivers/of/platform.c b/drivers/of/platform.c
> index 81c8c227ab6b..f2a5d679a324 100644
> --- a/drivers/of/platform.c
> +++ b/drivers/of/platform.c
> @@ -525,6 +525,7 @@ static int __init of_platform_default_populate_init(void)
>  	if (IS_ENABLED(CONFIG_PPC)) {
>  		struct device_node *boot_display = NULL;
>  		struct platform_device *dev;
> +		int display_number = 1;
>  		int ret;
>  
>  		/* Check if we have a MacOS display without a node spec */
> @@ -561,10 +562,15 @@ static int __init of_platform_default_populate_init(void)
>  			boot_display = node;
>  			break;
>  		}
> +
>  		for_each_node_by_type(node, "display") {
> +			char *buf[14];
>  			if (!of_get_property(node, "linux,opened", NULL) || node == boot_display)
>  				continue;
> -			of_platform_device_create(node, "of-display", NULL);
> +			ret = snprintf(buf, "of-display-%d", display_number++);
> +			if (ret >= sizeof(buf))
> +				continue;
> +			of_platform_device_create(node, buf, NULL);
>  		}
>  
>  	} else {
> -- 
> 2.35.3
> 

Thank you for the patch Michal!

It applies on 6.2-rc4 but I get this build error with my config:

 # make
  CALL    scripts/checksyscalls.sh
  CC      drivers/of/platform.o
drivers/of/platform.c: In function 'of_platform_default_populate_init':
drivers/of/platform.c:570:40: error: passing argument 1 of 'snprintf' from incompatible pointer type [-Werror=incompatible-pointer-types]
  570 |                         ret = snprintf(buf, "of-display-%d", display_number++);
      |                                        ^~~
      |                                        |
      |                                        char **
In file included from ./arch/powerpc/include/asm/page.h:11,
                 from ./arch/powerpc/include/asm/thread_info.h:13,
                 from ./include/linux/thread_info.h:60,
                 from ./arch/powerpc/include/asm/ptrace.h:342,
                 from ./arch/powerpc/include/asm/hw_irq.h:12,
                 from ./arch/powerpc/include/asm/irqflags.h:12,
                 from ./include/linux/irqflags.h:16,
                 from ./include/asm-generic/cmpxchg-local.h:6,
                 from ./arch/powerpc/include/asm/cmpxchg.h:755,
                 from ./arch/powerpc/include/asm/atomic.h:11,
                 from ./include/linux/atomic.h:7,
                 from ./include/linux/mm_types_task.h:13,
                 from ./include/linux/mm_types.h:5,
                 from ./include/linux/buildid.h:5,
                 from ./include/linux/module.h:14,
                 from drivers/of/platform.c:13:
./include/linux/kernel.h:213:20: note: expected 'char *' but argument is of type 'char **'
  213 | int snprintf(char *buf, size_t size, const char *fmt, ...);
      |              ~~~~~~^~~
drivers/of/platform.c:570:45: warning: passing argument 2 of 'snprintf' makes integer from pointer without a cast [-Wint-conversion]
  570 |                         ret = snprintf(buf, "of-display-%d", display_number++);
      |                                             ^~~~~~~~~~~~~~~
      |                                             |
      |                                             char *
./include/linux/kernel.h:213:32: note: expected 'size_t' {aka 'unsigned int'} but argument is of type 'char *'
  213 | int snprintf(char *buf, size_t size, const char *fmt, ...);
      |                         ~~~~~~~^~~~
drivers/of/platform.c:570:76: warning: passing argument 3 of 'snprintf' makes pointer from integer without a cast [-Wint-conversion]
  570 |                         ret = snprintf(buf, "of-display-%d", display_number++);
      |                                                              ~~~~~~~~~~~~~~^~
      |                                                                            |
      |                                                                            int
./include/linux/kernel.h:213:50: note: expected 'const char *' but argument is of type 'int'
  213 | int snprintf(char *buf, size_t size, const char *fmt, ...);
      |                                      ~~~~~~~~~~~~^~~
drivers/of/platform.c:573:57: error: passing argument 2 of 'of_platform_device_create' from incompatible pointer type [-Werror=incompatible-pointer-types]
  573 |                         of_platform_device_create(node, buf, NULL);
      |                                                         ^~~
      |                                                         |
      |                                                         char **
drivers/of/platform.c:211:57: note: expected 'const char *' but argument is of type 'char **'
  211 |                                             const char *bus_id,
      |                                             ~~~~~~~~~~~~^~~~~~
cc1: some warnings being treated as errors
make[3]: *** [scripts/Makefile.build:252: drivers/of/platform.o] Fehler 1
make[2]: *** [scripts/Makefile.build:504: drivers/of] Fehler 2
make[1]: *** [scripts/Makefile.build:504: drivers] Fehler 2
make: *** [Makefile:2008: .] Error 2


Regards,
Erhard

Michal Suchánek Jan. 18, 2023, 9:46 p.m. UTC | #3

On Wed, Jan 18, 2023 at 09:13:05PM +0100, Erhard F. wrote:
> On Tue, 17 Jan 2023 17:58:04 +0100
> Michal Suchanek <msuchanek@suse.de> wrote:
> 
> > Since Linux 5.19 this error is observed:
> > 
> > sysfs: cannot create duplicate filename '/devices/platform/of-display'
> > 
> > This is because multiple devices with the same name 'of-display' are
> > created on the same bus.
> > 
> > Update the code to create numbered device names for the non-boot
> > disaplay.
> > 
> > cc: linuxppc-dev@lists.ozlabs.org
> > References: https://bugzilla.kernel.org/show_bug.cgi?id=216095
> > Fixes: 52b1b46c39ae ("of: Create platform devices for OF framebuffers")
> > Reported-by: Erhard F. <erhard_f@mailbox.org>
> > Suggested-by: Thomas Zimmermann <tzimmermann@suse.de>
> > Signed-off-by: Michal Suchanek <msuchanek@suse.de>
> > ---
> >  drivers/of/platform.c | 8 +++++++-
> >  1 file changed, 7 insertions(+), 1 deletion(-)
> > 
> > diff --git a/drivers/of/platform.c b/drivers/of/platform.c
> > index 81c8c227ab6b..f2a5d679a324 100644
> > --- a/drivers/of/platform.c
> > +++ b/drivers/of/platform.c
> > @@ -525,6 +525,7 @@ static int __init of_platform_default_populate_init(void)
> >  	if (IS_ENABLED(CONFIG_PPC)) {
> >  		struct device_node *boot_display = NULL;
> >  		struct platform_device *dev;
> > +		int display_number = 1;
> >  		int ret;
> >  
> >  		/* Check if we have a MacOS display without a node spec */
> > @@ -561,10 +562,15 @@ static int __init of_platform_default_populate_init(void)
> >  			boot_display = node;
> >  			break;
> >  		}
> > +
> >  		for_each_node_by_type(node, "display") {
> > +			char *buf[14];
> >  			if (!of_get_property(node, "linux,opened", NULL) || node == boot_display)
> >  				continue;
> > -			of_platform_device_create(node, "of-display", NULL);
> > +			ret = snprintf(buf, "of-display-%d", display_number++);
> > +			if (ret >= sizeof(buf))
> > +				continue;
> > +			of_platform_device_create(node, buf, NULL);
> >  		}
> >  
> >  	} else {
> > -- 
> > 2.35.3
> > 
> 
> Thank you for the patch Michal!
> 
> It applies on 6.2-rc4 but I get this build error with my config:

Indeed, it's doubly bad.

Where is the kernel test robot when you need it?

It should not be that easy to miss this file but clearly it can happen.

I will send a fixup.

Sorry about the mess.

Thanks

Michal

Thomas Zimmermann Jan. 19, 2023, 8 a.m. UTC | #4

Hi Michal,

thanks for fixing this issue. But the review time was way too short. 
Please see my comments below.

Am 18.01.23 um 22:46 schrieb Michal Suchánek:
> On Wed, Jan 18, 2023 at 09:13:05PM +0100, Erhard F. wrote:
>> On Tue, 17 Jan 2023 17:58:04 +0100
>> Michal Suchanek <msuchanek@suse.de> wrote:
>>
>>> Since Linux 5.19 this error is observed:
>>>
>>> sysfs: cannot create duplicate filename '/devices/platform/of-display'
>>>
>>> This is because multiple devices with the same name 'of-display' are
>>> created on the same bus.
>>>
>>> Update the code to create numbered device names for the non-boot
>>> disaplay.
>>>
>>> cc: linuxppc-dev@lists.ozlabs.org
>>> References: https://bugzilla.kernel.org/show_bug.cgi?id=216095
>>> Fixes: 52b1b46c39ae ("of: Create platform devices for OF framebuffers")
>>> Reported-by: Erhard F. <erhard_f@mailbox.org>
>>> Suggested-by: Thomas Zimmermann <tzimmermann@suse.de>
>>> Signed-off-by: Michal Suchanek <msuchanek@suse.de>
>>> ---
>>>   drivers/of/platform.c | 8 +++++++-
>>>   1 file changed, 7 insertions(+), 1 deletion(-)
>>>
>>> diff --git a/drivers/of/platform.c b/drivers/of/platform.c
>>> index 81c8c227ab6b..f2a5d679a324 100644
>>> --- a/drivers/of/platform.c
>>> +++ b/drivers/of/platform.c
>>> @@ -525,6 +525,7 @@ static int __init of_platform_default_populate_init(void)
>>>   	if (IS_ENABLED(CONFIG_PPC)) {
>>>   		struct device_node *boot_display = NULL;
>>>   		struct platform_device *dev;
>>> +		int display_number = 1;
>>>   		int ret;
>>>   
>>>   		/* Check if we have a MacOS display without a node spec */
>>> @@ -561,10 +562,15 @@ static int __init of_platform_default_populate_init(void)
>>>   			boot_display = node;
>>>   			break;
>>>   		}
>>> +
>>>   		for_each_node_by_type(node, "display") {
>>> +			char *buf[14];
>>>   			if (!of_get_property(node, "linux,opened", NULL) || node == boot_display)
>>>   				continue;
>>> -			of_platform_device_create(node, "of-display", NULL);
>>> +			ret = snprintf(buf, "of-display-%d", display_number++);

Platform devices use a single dot (.) as separator before the index. 
Counting starts at zero. See /sys/bus/platform/ for examples. Can we 
please stick with that scheme? Generated names would then be 
of-display.0, of-display.1, etc.

Best regards
Thomas



>>> +			if (ret >= sizeof(buf))
>>> +				continue;
>>> +			of_platform_device_create(node, buf, NULL);
>>>   		}
>>>   
>>>   	} else {
>>> -- 
>>> 2.35.3
>>>
>>
>> Thank you for the patch Michal!
>>
>> It applies on 6.2-rc4 but I get this build error with my config:
> 
> Indeed, it's doubly bad.
> 
> Where is the kernel test robot when you need it?
> 
> It should not be that easy to miss this file but clearly it can happen.
> 
> I will send a fixup.
> 
> Sorry about the mess.
> 
> Thanks
> 
> Michal

-- 
Thomas Zimmermann
Graphics Driver Developer
SUSE Software Solutions Germany GmbH
Maxfeldstr. 5, 90409 Nürnberg, Germany
(HRB 36809, AG Nürnberg)
Geschäftsführer: Ivo Totev

Michal Suchánek Jan. 19, 2023, 9:01 a.m. UTC | #5

On Thu, Jan 19, 2023 at 09:00:44AM +0100, Thomas Zimmermann wrote:
> Hi Michal,
> 
> thanks for fixing this issue. But the review time was way too short. Please
> see my comments below.
> 
> Am 18.01.23 um 22:46 schrieb Michal Suchánek:
> > On Wed, Jan 18, 2023 at 09:13:05PM +0100, Erhard F. wrote:
> > > On Tue, 17 Jan 2023 17:58:04 +0100
> > > Michal Suchanek <msuchanek@suse.de> wrote:
> > > 
> > > > Since Linux 5.19 this error is observed:
> > > > 
> > > > sysfs: cannot create duplicate filename '/devices/platform/of-display'
> > > > 
> > > > This is because multiple devices with the same name 'of-display' are
> > > > created on the same bus.
> > > > 
> > > > Update the code to create numbered device names for the non-boot
> > > > disaplay.
> > > > 
> > > > cc: linuxppc-dev@lists.ozlabs.org
> > > > References: https://bugzilla.kernel.org/show_bug.cgi?id=216095
> > > > Fixes: 52b1b46c39ae ("of: Create platform devices for OF framebuffers")
> > > > Reported-by: Erhard F. <erhard_f@mailbox.org>
> > > > Suggested-by: Thomas Zimmermann <tzimmermann@suse.de>
> > > > Signed-off-by: Michal Suchanek <msuchanek@suse.de>
> > > > ---
> > > >   drivers/of/platform.c | 8 +++++++-
> > > >   1 file changed, 7 insertions(+), 1 deletion(-)
> > > > 
> > > > diff --git a/drivers/of/platform.c b/drivers/of/platform.c
> > > > index 81c8c227ab6b..f2a5d679a324 100644
> > > > --- a/drivers/of/platform.c
> > > > +++ b/drivers/of/platform.c
> > > > @@ -525,6 +525,7 @@ static int __init of_platform_default_populate_init(void)
> > > >   	if (IS_ENABLED(CONFIG_PPC)) {
> > > >   		struct device_node *boot_display = NULL;
> > > >   		struct platform_device *dev;
> > > > +		int display_number = 1;
> > > >   		int ret;
> > > >   		/* Check if we have a MacOS display without a node spec */
> > > > @@ -561,10 +562,15 @@ static int __init of_platform_default_populate_init(void)
> > > >   			boot_display = node;
> > > >   			break;
> > > >   		}
> > > > +
> > > >   		for_each_node_by_type(node, "display") {
> > > > +			char *buf[14];
> > > >   			if (!of_get_property(node, "linux,opened", NULL) || node == boot_display)
> > > >   				continue;
> > > > -			of_platform_device_create(node, "of-display", NULL);
> > > > +			ret = snprintf(buf, "of-display-%d", display_number++);
> 
> Platform devices use a single dot (.) as separator before the index.
> Counting starts at zero. See /sys/bus/platform/ for examples. Can we please
> stick with that scheme? Generated names would then be of-display.0,
> of-display.1, etc.

Yes, there was surprisingly no bikeshedding.

Do we also want to change the name of the device that did manage to
instantiate before?

This scheme changes the name only for those that did not in the past,
hence "of-display" and "of-display-%d", starting from 1.

Sure, replacing '-' with '.' is easy enough, and using the same format
for both as well.

Thanks

Michal

> 
> Best regards
> Thomas
> 
> 
> 
> > > > +			if (ret >= sizeof(buf))
> > > > +				continue;
> > > > +			of_platform_device_create(node, buf, NULL);
> > > >   		}
> > > >   	} else {
> > > > -- 
> > > > 2.35.3
> > > > 
> > > 
> > > Thank you for the patch Michal!
> > > 
> > > It applies on 6.2-rc4 but I get this build error with my config:
> > 
> > Indeed, it's doubly bad.
> > 
> > Where is the kernel test robot when you need it?
> > 
> > It should not be that easy to miss this file but clearly it can happen.
> > 
> > I will send a fixup.
> > 
> > Sorry about the mess.
> > 
> > Thanks
> > 
> > Michal
> 
> -- 
> Thomas Zimmermann
> Graphics Driver Developer
> SUSE Software Solutions Germany GmbH
> Maxfeldstr. 5, 90409 Nürnberg, Germany
> (HRB 36809, AG Nürnberg)
> Geschäftsführer: Ivo Totev

Thomas Zimmermann Jan. 19, 2023, 9:18 a.m. UTC | #6

Hi

Am 19.01.23 um 10:01 schrieb Michal Suchánek:
> On Thu, Jan 19, 2023 at 09:00:44AM +0100, Thomas Zimmermann wrote:
>> Hi Michal,
>>
>> thanks for fixing this issue. But the review time was way too short. Please
>> see my comments below.
>>
>> Am 18.01.23 um 22:46 schrieb Michal Suchánek:
>>> On Wed, Jan 18, 2023 at 09:13:05PM +0100, Erhard F. wrote:
>>>> On Tue, 17 Jan 2023 17:58:04 +0100
>>>> Michal Suchanek <msuchanek@suse.de> wrote:
>>>>
>>>>> Since Linux 5.19 this error is observed:
>>>>>
>>>>> sysfs: cannot create duplicate filename '/devices/platform/of-display'
>>>>>
>>>>> This is because multiple devices with the same name 'of-display' are
>>>>> created on the same bus.
>>>>>
>>>>> Update the code to create numbered device names for the non-boot
>>>>> disaplay.
>>>>>
>>>>> cc: linuxppc-dev@lists.ozlabs.org
>>>>> References: https://bugzilla.kernel.org/show_bug.cgi?id=216095
>>>>> Fixes: 52b1b46c39ae ("of: Create platform devices for OF framebuffers")
>>>>> Reported-by: Erhard F. <erhard_f@mailbox.org>
>>>>> Suggested-by: Thomas Zimmermann <tzimmermann@suse.de>
>>>>> Signed-off-by: Michal Suchanek <msuchanek@suse.de>
>>>>> ---
>>>>>    drivers/of/platform.c | 8 +++++++-
>>>>>    1 file changed, 7 insertions(+), 1 deletion(-)
>>>>>
>>>>> diff --git a/drivers/of/platform.c b/drivers/of/platform.c
>>>>> index 81c8c227ab6b..f2a5d679a324 100644
>>>>> --- a/drivers/of/platform.c
>>>>> +++ b/drivers/of/platform.c
>>>>> @@ -525,6 +525,7 @@ static int __init of_platform_default_populate_init(void)
>>>>>    	if (IS_ENABLED(CONFIG_PPC)) {
>>>>>    		struct device_node *boot_display = NULL;
>>>>>    		struct platform_device *dev;
>>>>> +		int display_number = 1;
>>>>>    		int ret;
>>>>>    		/* Check if we have a MacOS display without a node spec */
>>>>> @@ -561,10 +562,15 @@ static int __init of_platform_default_populate_init(void)
>>>>>    			boot_display = node;
>>>>>    			break;
>>>>>    		}
>>>>> +
>>>>>    		for_each_node_by_type(node, "display") {
>>>>> +			char *buf[14];

Another issue here: This should simply be buf[14]; not a pointer. Is 14 
chars enough for the string plus a full number?

>>>>>    			if (!of_get_property(node, "linux,opened", NULL) || node == boot_display)
>>>>>    				continue;
>>>>> -			of_platform_device_create(node, "of-display", NULL);
>>>>> +			ret = snprintf(buf, "of-display-%d", display_number++);

The second argument to snprintf() is sizeof(buf); the number of 
characters in buf.

>>
>> Platform devices use a single dot (.) as separator before the index.
>> Counting starts at zero. See /sys/bus/platform/ for examples. Can we please
>> stick with that scheme? Generated names would then be of-display.0,
>> of-display.1, etc.
> 
> Yes, there was surprisingly no bikeshedding.
> 
> Do we also want to change the name of the device that did manage to
> instantiate before?
> 
> This scheme changes the name only for those that did not in the past,
> hence "of-display" and "of-display-%d", starting from 1.

I find that very confusing. It is is better to count all devices from 0. 
I don't expect this to be an issue for userspace. But if necessary, 
devfs can create softlinks to of-display.0.

Best regards
Thomas

> 
> Sure, replacing '-' with '.' is easy enough, and using the same format
> for both as well.
> 
> Thanks
> 
> Michal
> 
>>
>> Best regards
>> Thomas
>>
>>
>>
>>>>> +			if (ret >= sizeof(buf))
>>>>> +				continue;
>>>>> +			of_platform_device_create(node, buf, NULL);
>>>>>    		}
>>>>>    	} else {
>>>>> -- 
>>>>> 2.35.3
>>>>>
>>>>
>>>> Thank you for the patch Michal!
>>>>
>>>> It applies on 6.2-rc4 but I get this build error with my config:
>>>
>>> Indeed, it's doubly bad.
>>>
>>> Where is the kernel test robot when you need it?
>>>
>>> It should not be that easy to miss this file but clearly it can happen.
>>>
>>> I will send a fixup.
>>>
>>> Sorry about the mess.
>>>
>>> Thanks
>>>
>>> Michal
>>
>> -- 
>> Thomas Zimmermann
>> Graphics Driver Developer
>> SUSE Software Solutions Germany GmbH
>> Maxfeldstr. 5, 90409 Nürnberg, Germany
>> (HRB 36809, AG Nürnberg)
>> Geschäftsführer: Ivo Totev
> 
> 
> 

-- 
Thomas Zimmermann
Graphics Driver Developer
SUSE Software Solutions Germany GmbH
Maxfeldstr. 5, 90409 Nürnberg, Germany
(HRB 36809, AG Nürnberg)
Geschäftsführer: Ivo Totev

diff mbox series

Patch

diff --git a/drivers/of/platform.c b/drivers/of/platform.c
index 81c8c227ab6b..f2a5d679a324 100644
--- a/drivers/of/platform.c
+++ b/drivers/of/platform.c
@@ -525,6 +525,7 @@  static int __init of_platform_default_populate_init(void)
 	if (IS_ENABLED(CONFIG_PPC)) {
 		struct device_node *boot_display = NULL;
 		struct platform_device *dev;
+		int display_number = 1;
 		int ret;
 
 		/* Check if we have a MacOS display without a node spec */
@@ -561,10 +562,15 @@  static int __init of_platform_default_populate_init(void)
 			boot_display = node;
 			break;
 		}
+
 		for_each_node_by_type(node, "display") {
+			char *buf[14];
 			if (!of_get_property(node, "linux,opened", NULL) || node == boot_display)
 				continue;
-			of_platform_device_create(node, "of-display", NULL);
+			ret = snprintf(buf, "of-display-%d", display_number++);
+			if (ret >= sizeof(buf))
+				continue;
+			of_platform_device_create(node, buf, NULL);
 		}
 
 	} else {