[PATCH 1/2] char: PC rtc: replace blacklist with whitelist

[PATCH 1/2] char: PC rtc: replace blacklist with whitelist

[Arnd Bergmann]

Every new architecture has to add itself to the growing list of those
that do not support the legacy PC RTC driver.

This replaces the long list of architectures that don't support it
with a shorter list of those that do.

The list is taken from those architectures that have a non-empty
asm/mc146818rtc.h header file and were not explicitly blacklisted.

Signed-off-by: Arnd Bergmann <arnd@arndb.de>
---
 drivers/char/Kconfig | 3 +--
 1 file changed, 1 insertion(+), 2 deletions(-)

diff --git a/drivers/char/Kconfig b/drivers/char/Kconfig
index a043107da2af..9716bc36495a 100644
--- a/drivers/char/Kconfig
+++ b/drivers/char/Kconfig
@@ -279,8 +279,7 @@ 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 && !BLACKFIN && !UML
+	depends on ALPHA || M32R || M68K || MIPS || MN10300 || PPC || X86
 	---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
-- 
2.7.0

[PATCH 2/2] char: genrtc: replace blacklist with whitelist

[Arnd Bergmann]

Every new architecture has to add itself to the growing list of those
that do not support the old "generic" RTC driver.

This replaces the long list of architectures that don't support it
with a shorter list of those that do.

The list is taken from those architectures that have a non-empty
asm/rtc.h header file and were not explicitly blacklisted.

Signed-off-by: Arnd Bergmann <arnd@arndb.de>
---
 drivers/char/Kconfig | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/drivers/char/Kconfig b/drivers/char/Kconfig
index 9716bc36495a..629f1ff389b6 100644
--- a/drivers/char/Kconfig
+++ b/drivers/char/Kconfig
@@ -327,7 +327,8 @@ config JS_RTC
 
 config GEN_RTC
 	tristate "Generic /dev/rtc emulation"
-	depends on RTC!=y && !IA64 && !ARM && !M32R && !MIPS && !SPARC && !FRV && !S390 && !SUPERH && !AVR32 && !BLACKFIN && !UML
+	depends on RTC!=y
+	depends on ALPHA || M68K || MN10300 || PARISC || PPC || X86
 	---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
-- 
2.7.0

Re: [PATCH 1/2] char: PC rtc: replace blacklist with whitelist

[Alexandre Belloni]

On 02/03/2016 at 10:48:50 +0100, Arnd Bergmann wrote :
> Every new architecture has to add itself to the growing list of those
> that do not support the legacy PC RTC driver.
> 
> This replaces the long list of architectures that don't support it
> with a shorter list of those that do.
> 
> The list is taken from those architectures that have a non-empty
> asm/mc146818rtc.h header file and were not explicitly blacklisted.
> 
> Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>

> ---
>  drivers/char/Kconfig | 3 +--
>  1 file changed, 1 insertion(+), 2 deletions(-)
> 
> diff --git a/drivers/char/Kconfig b/drivers/char/Kconfig
> index a043107da2af..9716bc36495a 100644
> --- a/drivers/char/Kconfig
> +++ b/drivers/char/Kconfig
> @@ -279,8 +279,7 @@ 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 && !BLACKFIN && !UML
> +	depends on ALPHA || M32R || M68K || MIPS || MN10300 || PPC || X86
>  	---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
> -- 
> 2.7.0
> 

-- 
Alexandre Belloni, Free Electrons
Embedded Linux, Kernel and Android engineering
http://free-electrons.com

Re: [PATCH 2/2] char: genrtc: replace blacklist with whitelist

[Alexandre Belloni]

On 02/03/2016 at 10:48:51 +0100, Arnd Bergmann wrote :
> Every new architecture has to add itself to the growing list of those
> that do not support the old "generic" RTC driver.
> 
> This replaces the long list of architectures that don't support it
> with a shorter list of those that do.
> 
> The list is taken from those architectures that have a non-empty
> asm/rtc.h header file and were not explicitly blacklisted.
> 
> Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>

> ---
>  drivers/char/Kconfig | 3 ++-
>  1 file changed, 2 insertions(+), 1 deletion(-)
> 
> diff --git a/drivers/char/Kconfig b/drivers/char/Kconfig
> index 9716bc36495a..629f1ff389b6 100644
> --- a/drivers/char/Kconfig
> +++ b/drivers/char/Kconfig
> @@ -327,7 +327,8 @@ config JS_RTC
>  
>  config GEN_RTC
>  	tristate "Generic /dev/rtc emulation"
> -	depends on RTC!=y && !IA64 && !ARM && !M32R && !MIPS && !SPARC && !FRV && !S390 && !SUPERH && !AVR32 && !BLACKFIN && !UML
> +	depends on RTC!=y
> +	depends on ALPHA || M68K || MN10300 || PARISC || PPC || X86
>  	---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
> -- 
> 2.7.0
> 

-- 
Alexandre Belloni, Free Electrons
Embedded Linux, Kernel and Android engineering
http://free-electrons.com

Re: [PATCH 1/2] char: PC rtc: replace blacklist with whitelist

[Geert Uytterhoeven]

On Wed, Mar 2, 2016 at 10:48 AM, Arnd Bergmann <arnd@arndb.de> wrote:
> Every new architecture has to add itself to the growing list of those
> that do not support the legacy PC RTC driver.
>
> This replaces the long list of architectures that don't support it
> with a shorter list of those that do.
>
> The list is taken from those architectures that have a non-empty
> asm/mc146818rtc.h header file and were not explicitly blacklisted.

M68K was blacklisted...

> Signed-off-by: Arnd Bergmann <arnd@arndb.de>
> ---
>  drivers/char/Kconfig | 3 +--
>  1 file changed, 1 insertion(+), 2 deletions(-)
>
> diff --git a/drivers/char/Kconfig b/drivers/char/Kconfig
> index a043107da2af..9716bc36495a 100644
> --- a/drivers/char/Kconfig
> +++ b/drivers/char/Kconfig
> @@ -279,8 +279,7 @@ 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 && !BLACKFIN && !UML
> +       depends on ALPHA || M32R || M68K || MIPS || MN10300 || PPC || X86

... so please drop it here.

Gr{oetje,eeting}s,

                        Geert

--
Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@linux-m68k.org

In personal conversations with technical people, I call myself a hacker. But
when I'm talking to journalists I just say "programmer" or something like that.
                                -- Linus Torvalds

Re: [PATCH 2/2] char: genrtc: replace blacklist with whitelist

[Geert Uytterhoeven]

On Wed, Mar 2, 2016 at 10:48 AM, Arnd Bergmann <arnd@arndb.de> wrote:
> Every new architecture has to add itself to the growing list of those
> that do not support the old "generic" RTC driver.
>
> This replaces the long list of architectures that don't support it
> with a shorter list of those that do.
>
> The list is taken from those architectures that have a non-empty
> asm/rtc.h header file and were not explicitly blacklisted.
>
> Signed-off-by: Arnd Bergmann <arnd@arndb.de>

Reviewed-by: Geert Uytterhoeven <geert@linux-m68k.org>

Gr{oetje,eeting}s,

                        Geert

--
Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@linux-m68k.org

In personal conversations with technical people, I call myself a hacker. But
when I'm talking to journalists I just say "programmer" or something like that.
                                -- Linus Torvalds

Re: [PATCH 1/2] char: PC rtc: replace blacklist with whitelist

[Alexandre Belloni]

Arnd,

On 02/03/2016 at 11:22:04 +0100, Geert Uytterhoeven wrote :
> On Wed, Mar 2, 2016 at 10:48 AM, Arnd Bergmann <arnd@arndb.de> wrote:
> > Every new architecture has to add itself to the growing list of those
> > that do not support the legacy PC RTC driver.
> >
> > This replaces the long list of architectures that don't support it
> > with a shorter list of those that do.
> >
> > The list is taken from those architectures that have a non-empty
> > asm/mc146818rtc.h header file and were not explicitly blacklisted.
> 
> M68K was blacklisted...
> 
> > Signed-off-by: Arnd Bergmann <arnd@arndb.de>
> > ---
> >  drivers/char/Kconfig | 3 +--
> >  1 file changed, 1 insertion(+), 2 deletions(-)
> >
> > diff --git a/drivers/char/Kconfig b/drivers/char/Kconfig
> > index a043107da2af..9716bc36495a 100644
> > --- a/drivers/char/Kconfig
> > +++ b/drivers/char/Kconfig
> > @@ -279,8 +279,7 @@ 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 && !BLACKFIN && !UML
> > +       depends on ALPHA || M32R || M68K || MIPS || MN10300 || PPC || X86
> 
> ... so please drop it here.
> 

Do you plan to resend that one?

-- 
Alexandre Belloni, Free Electrons
Embedded Linux, Kernel and Android engineering
http://free-electrons.com

Re: [PATCH 1/2] char: PC rtc: replace blacklist with whitelist

[Arnd Bergmann]

On Sunday 10 April 2016 17:43:52 Alexandre Belloni wrote:
> > >  config RTC
> > >         tristate "Enhanced Real Time Clock Support (legacy PC RTC driver)"
> > > -       depends on !PPC && !PARISC && !IA64 && !M68K && !SPARC && !FRV \
> > > -                       && !ARM && !SUPERH && !S390 && !AVR32 && !BLACKFIN && !UML
> > > +       depends on ALPHA || M32R || M68K || MIPS || MN10300 || PPC || X86
> > 
> > ... so please drop it here.
> > 
> 
> Do you plan to resend that one?
> 

Yes, it's in my queue for resending, together with some other RTC patches.

	Arnd

Re: [PATCH 1/2] char: PC rtc: replace blacklist with whitelist

[Arnd Bergmann]

On Wednesday 02 March 2016 11:22:04 Geert Uytterhoeven wrote:
> On Wed, Mar 2, 2016 at 10:48 AM, Arnd Bergmann <arnd@arndb.de> wrote:
> > Every new architecture has to add itself to the growing list of those
> > that do not support the legacy PC RTC driver.
> >
> > This replaces the long list of architectures that don't support it
> > with a shorter list of those that do.
> >
> > The list is taken from those architectures that have a non-empty
> > asm/mc146818rtc.h header file and were not explicitly blacklisted.
> 
> M68K was blacklisted...

I never got back to you on this topic, sorry about that. I've fixed
up the patch to leave out m68k now.

On a semi-related note, I see that m68k is one of the few architectures
still using the (other) genrtc driver. It would be nice to reduce that
list and change m68k to use its own rtc driver (ideally one per
platform), but the q40 platform is the only one providing
get_rtc_pll()/set_rtc_pll() for the RTC_PLL_GET/RTC_PLL_SET ioctl
commands.

If we do this change on top of the other m68k patch I have, the
rtc-generic driver should be usable as a full replacement for
genrtc.c on m68k and we can remove all the set_rtc_pll/get_rtc_pll
handling from genrtc.

diff --git a/arch/m68k/kernel/time.c b/arch/m68k/kernel/time.c
index 773b2187210d..f4781d612c37 100644
--- a/arch/m68k/kernel/time.c
+++ b/arch/m68k/kernel/time.c
@@ -100,7 +100,32 @@ static int rtc_generic_set_time(struct device *dev, struct rtc_time *tm)
 	return 0;
 }
 
+static int rtc_ioctl(struct device *dev, unsigned int cmd, unsigned long arg)
+{
+	struct rtc_pll_info pll;
+	struct rtc_pll_info __user *argp = (void __user *)arg;
+
+	switch (cmd) {
+	case RTC_PLL_GET:
+		if (!mach_get_rtc_pll || mach_get_rtc_pll(&pll))
+			return -EINVAL;
+		return copy_to_user(argp, &pll, sizeof pll) ? -EFAULT : 0;
+
+	case RTC_PLL_SET:
+		if (!mach_set_rtc_pll)
+			return -EINVAL;
+		if (!capable(CAP_SYS_TIME))
+			return -EACCES;
+		if (copy_from_user(&pll, argp, sizeof(pll)))
+			return -EFAULT;
+		return mach_set_rtc_pll(&pll);
+	}
+
+	return -ENOIOCTLCMD;
+}
+
 static const struct rtc_class_ops generic_rtc_ops = {
+	.ioctl = rtc_ioctl,
 	.read_time = rtc_generic_get_time,
 	.set_time = rtc_generic_set_time,
 };


	Arnd 

Re: [PATCH 1/2] char: PC rtc: replace blacklist with whitelist

[Geert Uytterhoeven]

Hi Arnd,

cc linux-m68k

On Sun, Apr 17, 2016 at 11:37 PM, Arnd Bergmann <arnd@arndb.de> wrote:
> On Wednesday 02 March 2016 11:22:04 Geert Uytterhoeven wrote:
>> On Wed, Mar 2, 2016 at 10:48 AM, Arnd Bergmann <arnd@arndb.de> wrote:
>> > Every new architecture has to add itself to the growing list of those
>> > that do not support the legacy PC RTC driver.
>> >
>> > This replaces the long list of architectures that don't support it
>> > with a shorter list of those that do.
>> >
>> > The list is taken from those architectures that have a non-empty
>> > asm/mc146818rtc.h header file and were not explicitly blacklisted.
>>
>> M68K was blacklisted...
>
> I never got back to you on this topic, sorry about that. I've fixed
> up the patch to leave out m68k now.
>
> On a semi-related note, I see that m68k is one of the few architectures
> still using the (other) genrtc driver. It would be nice to reduce that
> list and change m68k to use its own rtc driver (ideally one per

We do have hp_sdc_rtc (HP9000/300; why is that under drivers/input/misc/?),
and rtc-msm6242 and rtc-rp5c01 (both for Amiga).

> platform), but the q40 platform is the only one providing
> get_rtc_pll()/set_rtc_pll() for the RTC_PLL_GET/RTC_PLL_SET ioctl
> commands.

Do you mean this is a problem?

> If we do this change on top of the other m68k patch I have, the
> rtc-generic driver should be usable as a full replacement for
> genrtc.c on m68k and we can remove all the set_rtc_pll/get_rtc_pll
> handling from genrtc.
>
> diff --git a/arch/m68k/kernel/time.c b/arch/m68k/kernel/time.c
> index 773b2187210d..f4781d612c37 100644
> --- a/arch/m68k/kernel/time.c
> +++ b/arch/m68k/kernel/time.c
> @@ -100,7 +100,32 @@ static int rtc_generic_set_time(struct device *dev, struct rtc_time *tm)
>         return 0;
>  }
>
> +static int rtc_ioctl(struct device *dev, unsigned int cmd, unsigned long arg)
> +{
> +       struct rtc_pll_info pll;
> +       struct rtc_pll_info __user *argp = (void __user *)arg;
> +
> +       switch (cmd) {
> +       case RTC_PLL_GET:
> +               if (!mach_get_rtc_pll || mach_get_rtc_pll(&pll))
> +                       return -EINVAL;
> +               return copy_to_user(argp, &pll, sizeof pll) ? -EFAULT : 0;
> +
> +       case RTC_PLL_SET:
> +               if (!mach_set_rtc_pll)
> +                       return -EINVAL;
> +               if (!capable(CAP_SYS_TIME))
> +                       return -EACCES;
> +               if (copy_from_user(&pll, argp, sizeof(pll)))
> +                       return -EFAULT;
> +               return mach_set_rtc_pll(&pll);
> +       }
> +
> +       return -ENOIOCTLCMD;
> +}
> +
>  static const struct rtc_class_ops generic_rtc_ops = {
> +       .ioctl = rtc_ioctl,
>         .read_time = rtc_generic_get_time,
>         .set_time = rtc_generic_set_time,
>  };

Gr{oetje,eeting}s,

                        Geert

--
Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@linux-m68k.org

In personal conversations with technical people, I call myself a hacker. But
when I'm talking to journalists I just say "programmer" or something like that.
                                -- Linus Torvalds

Re: [PATCH 1/2] char: PC rtc: replace blacklist with whitelist

[Arnd Bergmann]

On Monday 18 April 2016 09:09:55 Geert Uytterhoeven wrote:
> Hi Arnd,
> 
> cc linux-m68k
> 
> On Sun, Apr 17, 2016 at 11:37 PM, Arnd Bergmann <arnd@arndb.de> wrote:
> > On Wednesday 02 March 2016 11:22:04 Geert Uytterhoeven wrote:
> >> On Wed, Mar 2, 2016 at 10:48 AM, Arnd Bergmann <arnd@arndb.de> wrote:
> >> > Every new architecture has to add itself to the growing list of those
> >> > that do not support the legacy PC RTC driver.
> >> >
> >> > This replaces the long list of architectures that don't support it
> >> > with a shorter list of those that do.
> >> >
> >> > The list is taken from those architectures that have a non-empty
> >> > asm/mc146818rtc.h header file and were not explicitly blacklisted.
> >>
> >> M68K was blacklisted...
> >
> > I never got back to you on this topic, sorry about that. I've fixed
> > up the patch to leave out m68k now.
> >
> > On a semi-related note, I see that m68k is one of the few architectures
> > still using the (other) genrtc driver. It would be nice to reduce that
> > list and change m68k to use its own rtc driver (ideally one per
> 
> We do have hp_sdc_rtc (HP9000/300; why is that under drivers/input/misc/?),
> and rtc-msm6242 and rtc-rp5c01 (both for Amiga).

fwiw, the hp_sdc_rtc driver does not actually implement the RTC ioctls
(they are there, but commented out).

The other ones are good, you just have two incompatible ways of doing
it because the drivers/rtc subsystem is can not be built into the
kernel at the same time as the old gen_rtc driver for the q40.

> > platform), but the q40 platform is the only one providing
> > get_rtc_pll()/set_rtc_pll() for the RTC_PLL_GET/RTC_PLL_SET ioctl
> > commands.
> 
> Do you mean this is a problem?

Not a big one, assuming that either nobody actually needs these ioctls
(very likely), or they don't care about having a single kernel for
q40 and the other platforms.

The main issue I see is migrating architectures over from gen_rtc to
rtc-generic over time, but this effort has been going on for at least
a decade and there is no rush, but it would still be nice.

	Arnd