[PATCH] drivers/char/rtc: disable legacy RTC driver on Blackfin systems

[PATCH] drivers/char/rtc: disable legacy RTC driver on Blackfin systems

[Mike Frysinger]

Blackfin platforms do not support the hardware which this driver drives.

Signed-off-by: Mike Frysinger <vapier@gentoo.org>
---
 drivers/char/Kconfig |    2 +-
 1 files changed, 1 insertions(+), 1 deletions(-)

diff --git a/drivers/char/Kconfig b/drivers/char/Kconfig
index 735bbe2..2f7363d 100644
--- a/drivers/char/Kconfig
+++ b/drivers/char/Kconfig
@@ -794,7 +794,7 @@ if RTC_LIB=n
 config RTC
 	tristate "Enhanced Real Time Clock Support (legacy PC RTC driver)"
 	depends on !PPC && !PARISC && !IA64 && !M68K && !SPARC && !FRV \
-			&& !ARM && !SUPERH && !S390 && !AVR32
+			&& !ARM && !SUPERH && !S390 && !AVR32 && !BLACKFIN
 	---help---
 	  If you say Y here and create a character special file /dev/rtc with
 	  major number 10 and minor number 135 using mknod ("man mknod"), you
-- 
1.6.3.1

Re: [PATCH] drivers/char/rtc: disable legacy RTC driver on Blackfin systems

[Christoph Hellwig]

On Tue, May 26, 2009 at 06:10:33AM -0400, Mike Frysinger wrote:
>  	tristate "Enhanced Real Time Clock Support (legacy PC RTC driver)"
>  	depends on !PPC && !PARISC && !IA64 && !M68K && !SPARC && !FRV \
> -			&& !ARM && !SUPERH && !S390 && !AVR32
> +			&& !ARM && !SUPERH && !S390 && !AVR32 && !BLACKFIN

Maybe it's better to have a positive dependency for those that actually
support it these days?  Based on the above list that would be:

	depends on ALPHA || CRIS || H8300 || M32R || MICROBLAZE ||
		   MIPS || MN10300 || SH || X86 || XTENSA

and I would not be surprised if some of the above don't actually support
it either..

Re: [rtc-linux] Re: [PATCH] drivers/char/rtc: disable legacy RTC driver on Blackfin systems

[Mike Frysinger]

On Tue, May 26, 2009 at 06:25, Christoph Hellwig wrote:
> On Tue, May 26, 2009 at 06:10:33AM -0400, Mike Frysinger wrote:
>>       tristate "Enhanced Real Time Clock Support (legacy PC RTC driver)"
>>       depends on !PPC && !PARISC && !IA64 && !M68K && !SPARC && !FRV \
>> -                     && !ARM && !SUPERH && !S390 && !AVR32
>> +                     && !ARM && !SUPERH && !S390 && !AVR32 && !BLACKFIN
>
> Maybe it's better to have a positive dependency for those that actually
> support it these days?  Based on the above list that would be:
>
>        depends on ALPHA || CRIS || H8300 || M32R || MICROBLAZE ||
>                   MIPS || MN10300 || SH || X86 || XTENSA
>
> and I would not be surprised if some of the above don't actually support
> it either..

it was my understanding that this driver was destined to be dropped
down the line ... easier to extend the cruft for now than try to ping
arch maintainers for confirmation ...
-mike

Re: [PATCH] drivers/char/rtc: disable legacy RTC driver on Blackfin systems

[Paul Mundt]

On Tue, May 26, 2009 at 06:25:02AM -0400, Christoph Hellwig wrote:
> On Tue, May 26, 2009 at 06:10:33AM -0400, Mike Frysinger wrote:
> >  	tristate "Enhanced Real Time Clock Support (legacy PC RTC driver)"
> >  	depends on !PPC && !PARISC && !IA64 && !M68K && !SPARC && !FRV \
> > -			&& !ARM && !SUPERH && !S390 && !AVR32
> > +			&& !ARM && !SUPERH && !S390 && !AVR32 && !BLACKFIN
> 
> Maybe it's better to have a positive dependency for those that actually
> support it these days?  Based on the above list that would be:
> 
> 	depends on ALPHA || CRIS || H8300 || M32R || MICROBLAZE ||
> 		   MIPS || MN10300 || SH || X86 || XTENSA
> 
> and I would not be surprised if some of the above don't actually support
> it either..

SH shouldn't be included it, we've never supported it. Out of the ones
that do support this interface, I would guess that they should require
little to no modification to work with drivers/rtc/rtc-cmos.c.

Out of the ones that don't actually support this interface but never
bothered updating the Kconfig bits.. none of h8300/microblaze/xtensa
define any of the CMOS_READ/WRITE() accessors, so this has no chance at
all of working there.

Now to narrow that list down a bit more, both m32r and cris primarily use
this interface for their ds1302 RTC, which I added a stub driver for in
drivers/rtc/rtc-ds1302.c some time ago. With a bit of cleanup on the
driver side and a bit of a push from the architecture side, they should
also be able to just use the drivers/rtc version directly. I've offered
to help with the conversion for these platforms before, but neither
maintainer seemed terribly responsive.

Which basically leaves just alpha, mips, mn10300, and x86. I would be
surprised if these don't work with rtc-cmos already today.

Re: [PATCH] drivers/char/rtc: disable legacy RTC driver on Blackfin systems

[Andrew Morton]

On Tue, 26 May 2009 06:25:02 -0400
Christoph Hellwig <hch@infradead.org> wrote:

> On Tue, May 26, 2009 at 06:10:33AM -0400, Mike Frysinger wrote:
> >  	tristate "Enhanced Real Time Clock Support (legacy PC RTC driver)"
> >  	depends on !PPC && !PARISC && !IA64 && !M68K && !SPARC && !FRV \
> > -			&& !ARM && !SUPERH && !S390 && !AVR32
> > +			&& !ARM && !SUPERH && !S390 && !AVR32 && !BLACKFIN
> 
> Maybe it's better to have a positive dependency for those that actually
> support it these days?

yeah, we do this rather a lot and it's pretty stupid.

>  Based on the above list that would be:
> 
> 	depends on ALPHA || CRIS || H8300 || M32R || MICROBLAZE ||
> 		   MIPS || MN10300 || SH || X86 || XTENSA
> 
> and I would not be surprised if some of the above don't actually support
> it either..

It would be better to make this driver depend on simply CONFIG_WANT_RTC
or similar and then select CONFIG_WANT_RTC in the relevant
arch/foo/Kconfig files.