[PATCH 1/3] rtc: stm32: remove __exit annotation on remove callback

[PATCH 1/3] rtc: stm32: remove __exit annotation on remove callback

[Arnd Bergmann]

The remove function can be called at runtime for a manual 'unbind'
operation and must not be left out from a built-in driver, as kbuild
complains:

`stm32_rtc_remove' referenced in section `.data.stm32_rtc_driver' of drivers/rtc/rtc-stm32.o: defined in discarded section `.exit.text' of drivers/rtc/rtc-stm32.o

This removes the extraneous annotation.

Fixes: 4e64350f42e2 ("rtc: add STM32 RTC driver")
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
---
 drivers/rtc/rtc-stm32.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/rtc/rtc-stm32.c b/drivers/rtc/rtc-stm32.c
index c4789b5a5d81..3513e052722f 100644
--- a/drivers/rtc/rtc-stm32.c
+++ b/drivers/rtc/rtc-stm32.c
@@ -657,7 +657,7 @@ static int stm32_rtc_probe(struct platform_device *pdev)
 	return ret;
 }
 
-static int __exit stm32_rtc_remove(struct platform_device *pdev)
+static int stm32_rtc_remove(struct platform_device *pdev)
 {
 	struct stm32_rtc *rtc = platform_get_drvdata(pdev);
 	unsigned int cr;
-- 
2.9.0

[PATCH 2/3] rtc: stm32: fix building without CONFIG_OF

[Arnd Bergmann]

The new driver has a stray #ifdef in it that causes a build error:

drivers/rtc/rtc-stm32.c:718:21: error: 'stm32_rtc_of_match' undeclared here (not in a function); did you mean 'stm32_rtc_pm_ops'?

As the #ifdef serves no purpose here, let's just remove it.

Fixes: 4e64350f42e2 ("rtc: add STM32 RTC driver")
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
---
 drivers/rtc/rtc-stm32.c | 2 --
 1 file changed, 2 deletions(-)

diff --git a/drivers/rtc/rtc-stm32.c b/drivers/rtc/rtc-stm32.c
index 3513e052722f..8c599f52124c 100644
--- a/drivers/rtc/rtc-stm32.c
+++ b/drivers/rtc/rtc-stm32.c
@@ -490,13 +490,11 @@ static const struct rtc_class_ops stm32_rtc_ops = {
 	.alarm_irq_enable = stm32_rtc_alarm_irq_enable,
 };
 
-#ifdef CONFIG_OF
 static const struct of_device_id stm32_rtc_of_match[] = {
 	{ .compatible = "st,stm32-rtc" },
 	{}
 };
 MODULE_DEVICE_TABLE(of, stm32_rtc_of_match);
-#endif
 
 static int stm32_rtc_init(struct platform_device *pdev,
 			  struct stm32_rtc *rtc)
-- 
2.9.0

[PATCH 3/3] rtc: stm32: use 32-bit cast for BIT() macro

[Arnd Bergmann]

Using the ~ operator on a BIT() constant results in a large 'unsigned long'
constant that won't fit into an 'unsigned int' function argument on 64-bit
architectures, resulting in a harmless build warning in x86 allmodconfig:

drivers/rtc/rtc-stm32.c: In function 'stm32_rtc_probe':
drivers/rtc/rtc-stm32.c:651:51: error: large integer implicitly truncated to unsigned type [-Werror=overflow]
  regmap_update_bits(rtc->dbp, PWR_CR, PWR_CR_DBP, ~PWR_CR_DBP);

This works around the warning by adding an explict cast to 'u32', but
that is unfortunately a bit ugly and I feel there should be a better
way to do this, possibly with some changes to either the bitops.h
header or the regmap API.

Cc: Mark Brown <broonie@kernel.org>
Fixes: 4e64350f42e2 ("rtc: add STM32 RTC driver")
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
---
 drivers/rtc/rtc-stm32.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/rtc/rtc-stm32.c b/drivers/rtc/rtc-stm32.c
index 8c599f52124c..05d3dc89e55f 100644
--- a/drivers/rtc/rtc-stm32.c
+++ b/drivers/rtc/rtc-stm32.c
@@ -92,7 +92,7 @@
 /* STM32_PWR_CR */
 #define PWR_CR				0x00
 /* STM32_PWR_CR bit field */
-#define PWR_CR_DBP			BIT(8)
+#define PWR_CR_DBP			(u32)BIT(8)
 
 struct stm32_rtc {
 	struct rtc_device *rtc_dev;
-- 
2.9.0

Re: [PATCH 3/3] rtc: stm32: use 32-bit cast for BIT() macro

[Russell King - ARM Linux]

On Fri, Jan 13, 2017 at 04:32:53PM +0100, Arnd Bergmann wrote:
> -#define PWR_CR_DBP			BIT(8)
> +#define PWR_CR_DBP			(u32)BIT(8)

Shouldn't that have parens around it as it's no longer a simple expression.

-- 
RMK's Patch system: http://www.armlinux.org.uk/developer/patches/
FTTC broadband for 0.8mile line: currently at 9.6Mbps down 400kbps up
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Re: [PATCH 3/3] rtc: stm32: use 32-bit cast for BIT() macro

[Alexandre Belloni]

On 13/01/2017 at 15:52:29 +0000, Russell King - ARM Linux wrote :
> On Fri, Jan 13, 2017 at 04:32:53PM +0100, Arnd Bergmann wrote:
> > -#define PWR_CR_DBP			BIT(8)
> > +#define PWR_CR_DBP			(u32)BIT(8)
> 
> Shouldn't that have parens around it as it's no longer a simple expression.
> 

Yes, at least checkpatch complains about it.

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

Re: [PATCH 3/3] rtc: stm32: use 32-bit cast for BIT() macro

[Amelie DELAUNAY]

Hi Arnd,

On 01/13/2017 04:32 PM, Arnd Bergmann wrote:
> Using the ~ operator on a BIT() constant results in a large 'unsigned long'
> constant that won't fit into an 'unsigned int' function argument on 64-bit
> architectures, resulting in a harmless build warning in x86 allmodconfig:
>
> drivers/rtc/rtc-stm32.c: In function 'stm32_rtc_probe':
> drivers/rtc/rtc-stm32.c:651:51: error: large integer implicitly truncated to unsigned type [-Werror=overflow]
>   regmap_update_bits(rtc->dbp, PWR_CR, PWR_CR_DBP, ~PWR_CR_DBP);
I thought I would fix this warning by replacing all ~PWR_CR_DBP by 0, 
because the mask PWR_CR_DBP prevents other bits to be cleared.
In this way, I avoid the ugly cast...
>
> This works around the warning by adding an explict cast to 'u32', but
> that is unfortunately a bit ugly and I feel there should be a better
> way to do this, possibly with some changes to either the bitops.h
> header or the regmap API.
>
> Cc: Mark Brown <broonie@kernel.org>
> Fixes: 4e64350f42e2 ("rtc: add STM32 RTC driver")
> Signed-off-by: Arnd Bergmann <arnd@arndb.de>
> ---
>  drivers/rtc/rtc-stm32.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/drivers/rtc/rtc-stm32.c b/drivers/rtc/rtc-stm32.c
> index 8c599f52124c..05d3dc89e55f 100644
> --- a/drivers/rtc/rtc-stm32.c
> +++ b/drivers/rtc/rtc-stm32.c
> @@ -92,7 +92,7 @@
>  /* STM32_PWR_CR */
>  #define PWR_CR				0x00
>  /* STM32_PWR_CR bit field */
> -#define PWR_CR_DBP			BIT(8)
> +#define PWR_CR_DBP			(u32)BIT(8)
>
>  struct stm32_rtc {
>  	struct rtc_device *rtc_dev;
>

Regards,
Amelie

Re: [PATCH 3/3] rtc: stm32: use 32-bit cast for BIT() macro

[Arnd Bergmann]

On Fri, Jan 13, 2017 at 4:56 PM, Amelie DELAUNAY <amelie.delaunay@st.com> wrote:
> On 01/13/2017 04:32 PM, Arnd Bergmann wrote:
>>
>> Using the ~ operator on a BIT() constant results in a large 'unsigned
>> long'
>> constant that won't fit into an 'unsigned int' function argument on 64-bit
>> architectures, resulting in a harmless build warning in x86 allmodconfig:
>>
>> drivers/rtc/rtc-stm32.c: In function 'stm32_rtc_probe':
>> drivers/rtc/rtc-stm32.c:651:51: error: large integer implicitly truncated
>> to unsigned type [-Werror=overflow]
>>   regmap_update_bits(rtc->dbp, PWR_CR, PWR_CR_DBP, ~PWR_CR_DBP);
>
> I thought I would fix this warning by replacing all ~PWR_CR_DBP by 0,
> because the mask PWR_CR_DBP prevents other bits to be cleared.
> In this way, I avoid the ugly cast...

Good idea, much nicer than mine! Can you send that patch?

    Arnd

Re: [PATCH 1/3] rtc: stm32: remove __exit annotation on remove callback

[Alexandre Belloni]

On 13/01/2017 at 16:32:51 +0100, Arnd Bergmann wrote :
> The remove function can be called at runtime for a manual 'unbind'
> operation and must not be left out from a built-in driver, as kbuild
> complains:
> 
> `stm32_rtc_remove' referenced in section `.data.stm32_rtc_driver' of drivers/rtc/rtc-stm32.o: defined in discarded section `.exit.text' of drivers/rtc/rtc-stm32.o
> 
> This removes the extraneous annotation.
> 
> Fixes: 4e64350f42e2 ("rtc: add STM32 RTC driver")
> Signed-off-by: Arnd Bergmann <arnd@arndb.de>
> ---
>  drivers/rtc/rtc-stm32.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
> 
Applied, thanks.

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

Re: [PATCH 2/3] rtc: stm32: fix building without CONFIG_OF

[Alexandre Belloni]

On 13/01/2017 at 16:32:52 +0100, Arnd Bergmann wrote :
> The new driver has a stray #ifdef in it that causes a build error:
> 
> drivers/rtc/rtc-stm32.c:718:21: error: 'stm32_rtc_of_match' undeclared here (not in a function); did you mean 'stm32_rtc_pm_ops'?
> 
> As the #ifdef serves no purpose here, let's just remove it.
> 
> Fixes: 4e64350f42e2 ("rtc: add STM32 RTC driver")
> Signed-off-by: Arnd Bergmann <arnd@arndb.de>
> ---
>  drivers/rtc/rtc-stm32.c | 2 --
>  1 file changed, 2 deletions(-)
> 
Applied, thanks.

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