diff mbox

tty/serial: atmel_serial: Fix device tree documentation

Message ID 1397487482-3816-1-git-send-email-richard.genoud@gmail.com (mailing list archive)
State New, archived
Headers show

Commit Message

Richard Genoud April 14, 2014, 2:58 p.m. UTC
RTS pin is an active low pin.
For now, this doesn't change anything as the ACTIVE_LOW flag is not
handled in atmel_serial, but it will be in 3.16.

Signed-off-by: Richard Genoud <richard.genoud@gmail.com>
---
 Documentation/devicetree/bindings/serial/atmel-usart.txt | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

Comments

Ludovic Desroches April 14, 2014, 3:22 p.m. UTC | #1
Hi Richard,

On Mon, Apr 14, 2014 at 04:58:02PM +0200, Richard Genoud wrote:
> RTS pin is an active low pin.
> For now, this doesn't change anything as the ACTIVE_LOW flag is not
> handled in atmel_serial, but it will be in 3.16.
> 
> Signed-off-by: Richard Genoud <richard.genoud@gmail.com>
> ---
>  Documentation/devicetree/bindings/serial/atmel-usart.txt | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/Documentation/devicetree/bindings/serial/atmel-usart.txt b/Documentation/devicetree/bindings/serial/atmel-usart.txt
> index 17c1042b2df8..2f7aad71b3c9 100644
> --- a/Documentation/devicetree/bindings/serial/atmel-usart.txt
> +++ b/Documentation/devicetree/bindings/serial/atmel-usart.txt
> @@ -35,7 +35,7 @@ Example:
>  		clock-names = "usart";
>  		atmel,use-dma-rx;
>  		atmel,use-dma-tx;
> -		rts-gpios = <&pioD 15 0>;
> +		rts-gpios = <&pioD 15 GPIO_ACTIVE_LOW>;

I was told we should not use macros here. If it is still the truth:

rts-gpios = <&pioD 15 1>;


Ludovic

>  	};
>  
>  - use DMA:
> -- 
> 1.8.5.5
> 
> 
> _______________________________________________
> linux-arm-kernel mailing list
> linux-arm-kernel@lists.infradead.org
> http://lists.infradead.org/mailman/listinfo/linux-arm-kernel
Richard Genoud April 15, 2014, 7:14 a.m. UTC | #2
2014-04-14 17:22 GMT+02:00 Ludovic Desroches <ludovic.desroches@atmel.com>:
> Hi Richard,
>
> On Mon, Apr 14, 2014 at 04:58:02PM +0200, Richard Genoud wrote:
>> RTS pin is an active low pin.
>> For now, this doesn't change anything as the ACTIVE_LOW flag is not
>> handled in atmel_serial, but it will be in 3.16.
>>
>> Signed-off-by: Richard Genoud <richard.genoud@gmail.com>
>> ---
>>  Documentation/devicetree/bindings/serial/atmel-usart.txt | 2 +-
>>  1 file changed, 1 insertion(+), 1 deletion(-)
>>
>> diff --git a/Documentation/devicetree/bindings/serial/atmel-usart.txt b/Documentation/devicetree/bindings/serial/atmel-usart.txt
>> index 17c1042b2df8..2f7aad71b3c9 100644
>> --- a/Documentation/devicetree/bindings/serial/atmel-usart.txt
>> +++ b/Documentation/devicetree/bindings/serial/atmel-usart.txt
>> @@ -35,7 +35,7 @@ Example:
>>               clock-names = "usart";
>>               atmel,use-dma-rx;
>>               atmel,use-dma-tx;
>> -             rts-gpios = <&pioD 15 0>;
>> +             rts-gpios = <&pioD 15 GPIO_ACTIVE_LOW>;
>
> I was told we should not use macros here. If it is still the truth:
>
> rts-gpios = <&pioD 15 1>;
That's right !
I do not totally get why, but macros aren't used in the documentation
(maybe that macros names may change, whereas numbers wont').
I'll resend this.

Thanks !

Richard.
Richard Genoud April 15, 2014, 7:39 a.m. UTC | #3
On 14/04/2014 17:22, Ludovic Desroches wrote:
> Hi Richard,
> 
> On Mon, Apr 14, 2014 at 04:58:02PM +0200, Richard Genoud wrote:
>> RTS pin is an active low pin.
>> For now, this doesn't change anything as the ACTIVE_LOW flag is not
>> handled in atmel_serial, but it will be in 3.16.
>>
>> Signed-off-by: Richard Genoud <richard.genoud@gmail.com>
>> ---
>>  Documentation/devicetree/bindings/serial/atmel-usart.txt | 2 +-
>>  1 file changed, 1 insertion(+), 1 deletion(-)
>>
>> diff --git a/Documentation/devicetree/bindings/serial/atmel-usart.txt b/Documentation/devicetree/bindings/serial/atmel-usart.txt
>> index 17c1042b2df8..2f7aad71b3c9 100644
>> --- a/Documentation/devicetree/bindings/serial/atmel-usart.txt
>> +++ b/Documentation/devicetree/bindings/serial/atmel-usart.txt
>> @@ -35,7 +35,7 @@ Example:
>>  		clock-names = "usart";
>>  		atmel,use-dma-rx;
>>  		atmel,use-dma-tx;
>> -		rts-gpios = <&pioD 15 0>;
>> +		rts-gpios = <&pioD 15 GPIO_ACTIVE_LOW>;
> 
> I was told we should not use macros here. If it is still the truth:
> 
> rts-gpios = <&pioD 15 1>;

But I'd really like to know if macros are forbidden in DT documentation and why...
Because, IMHO, <&pioD 15 1> talks less that <&pioD 15 GPIO_ACTIVE_LOW>.
Which is a shame in a documentation.

Rob, any idea on that ?

(actually, I missed some uses of GPIO_ACTIVE_ macros in Documentation :)
git grep GPIO_ACTIVE Documentation/devicetree/bindings/
Documentation/devicetree/bindings/gpio/gpio-davinci.txt:                gpios = <&gpio 10 GPIO_ACTIVE_HIGH>;
Documentation/devicetree/bindings/gpio/gpio-davinci.txt:                gpios = <&gpio 11 GPIO_ACTIVE_HIGH>;
Documentation/devicetree/bindings/gpio/gpio-lp3943.txt:         gpios = <&gpioex 9 GPIO_ACTIVE_LOW>;
Documentation/devicetree/bindings/gpio/gpio-lp3943.txt:         gpios = <&gpioex 10 GPIO_ACTIVE_LOW>;
Documentation/devicetree/bindings/gpio/gpio-pcf857x.txt:    GPIO_ACTIVE_HIGH and GPIO_ACTIVE_LOW flags are supported.
Documentation/devicetree/bindings/gpio/gpio-tz1090-pdc.txt:      GPIO_ACTIVE_HIGH
Documentation/devicetree/bindings/gpio/gpio-tz1090-pdc.txt:      GPIO_ACTIVE_LOW
Documentation/devicetree/bindings/gpio/gpio-tz1090.txt:        GPIO_ACTIVE_HIGH
Documentation/devicetree/bindings/gpio/gpio-tz1090.txt:        GPIO_ACTIVE_LOW
Documentation/devicetree/bindings/gpio/renesas,gpio-rcar.txt:    GPIO_ACTIVE_HIGH and GPIO_ACTIVE_LOW flags are supported.
Documentation/devicetree/bindings/input/gpio-beeper.txt:                gpios = <&gpio3 23 GPIO_ACTIVE_HIGH>;
Documentation/devicetree/bindings/mmc/mmc.txt:also be specified using the OF_GPIO_ACTIVE_LOW flag. This creates an ambiguity
Documentation/devicetree/bindings/mmc/mmc.txt:OF_GPIO_ACTIVE_LOW flag clear and specifying the respective *-inverted
Documentation/devicetree/bindings/net/nfc/trf7970a.txt:         ti,enable-gpios = <&gpio2 2 GPIO_ACTIVE_LOW>,
Documentation/devicetree/bindings/net/nfc/trf7970a.txt:                           <&gpio2 5 GPIO_ACTIVE_LOW>;
Documentation/devicetree/bindings/net/wireless/ti,wl1251.txt:           ti,power-gpio = <&gpio3 23 GPIO_ACTIVE_HIGH>; /* 87 */
Documentation/devicetree/bindings/pinctrl/renesas,pfc-pinctrl.txt:    GPIO_ACTIVE_HIGH and GPIO_ACTIVE_LOW flags are supported.
Documentation/devicetree/bindings/pinctrl/renesas,pfc-pinctrl.txt:                      gpios = <&pfc 20 GPIO_ACTIVE_LOW>;
Documentation/devicetree/bindings/power/isp1704.txt:    nxp,enable-gpio = <&gpio3 3 GPIO_ACTIVE_LOW>;
Documentation/devicetree/bindings/sound/max98090.txt:   interrupts = <TEGRA_GPIO(H, 4) GPIO_ACTIVE_HIGH>;
Documentation/devicetree/bindings/sound/rt5640.txt:     interrupts = <TEGRA_GPIO(W, 3) GPIO_ACTIVE_HIGH>;
Documentation/devicetree/bindings/sound/rt5640.txt:             <&gpio TEGRA_GPIO(V, 3) GPIO_ACTIVE_HIGH>;
Documentation/devicetree/bindings/sound/tpa6130a2.txt:  power-gpio = <&gpio4 2 GPIO_ACTIVE_HIGH>;
Documentation/devicetree/bindings/usb/usb-nop-xceiv.txt:                reset-gpios = <&gpio1 7 GPIO_ACTIVE_LOW>;
Documentation/devicetree/bindings/video/backlight/gpio-backlight.txt:           gpios = <&gpio3 4 GPIO_ACTIVE_HIGH>;
Documentation/devicetree/bindings/video/panel-dsi-cm.txt:       reset-gpios = <&gpio4 6 GPIO_ACTIVE_HIGH>;
Documentation/devicetree/bindings/video/sony,acx565akm.txt:     reset-gpios = <&gpio3 26 GPIO_ACTIVE_HIGH>; /* 90 */
Documentation/devicetree/bindings/video/ti,omap-dss.txt:                gpios = <&gpio1 0 GPIO_ACTIVE_LOW>;     /* 0, power-down */
Documentation/devicetree/bindings/video/ti,omap-dss.txt:                gpios = <&gpio2 28 GPIO_ACTIVE_HIGH>,   /* 60, CT CP HPD */
Documentation/devicetree/bindings/video/ti,omap-dss.txt:                        <&gpio2 9 GPIO_ACTIVE_HIGH>,    /* 41, LS OE */
Documentation/devicetree/bindings/video/ti,omap-dss.txt:                        <&gpio2 31 GPIO_ACTIVE_HIGH>;   /* 63, HPD */
Documentation/devicetree/bindings/video/ti,tfp410.txt:  powerdown-gpios = <&twl_gpio 2 GPIO_ACTIVE_LOW>;
Documentation/devicetree/bindings/video/ti,tpd12s015.txt:       gpios = <&gpio2 28 GPIO_ACTIVE_HIGH>,   /* 60, CT CP HPD */
Documentation/devicetree/bindings/video/ti,tpd12s015.txt:               <&gpio2 9 GPIO_ACTIVE_HIGH>,    /* 41, LS OE */
Documentation/devicetree/bindings/video/ti,tpd12s015.txt:               <&gpio2 31 GPIO_ACTIVE_HIGH>;   /* 63, HPD */
Documentation/devicetree/bindings/watchdog/gpio-wdt.txt:                gpios = <&gpio3 9 GPIO_ACTIVE_LOW>;

Richard.
Ludovic Desroches April 15, 2014, 8 a.m. UTC | #4
On Tue, Apr 15, 2014 at 09:39:59AM +0200, Richard Genoud wrote:
> On 14/04/2014 17:22, Ludovic Desroches wrote:
> > Hi Richard,
> > 
> > On Mon, Apr 14, 2014 at 04:58:02PM +0200, Richard Genoud wrote:
> >> RTS pin is an active low pin.
> >> For now, this doesn't change anything as the ACTIVE_LOW flag is not
> >> handled in atmel_serial, but it will be in 3.16.
> >>
> >> Signed-off-by: Richard Genoud <richard.genoud@gmail.com>
> >> ---
> >>  Documentation/devicetree/bindings/serial/atmel-usart.txt | 2 +-
> >>  1 file changed, 1 insertion(+), 1 deletion(-)
> >>
> >> diff --git a/Documentation/devicetree/bindings/serial/atmel-usart.txt b/Documentation/devicetree/bindings/serial/atmel-usart.txt
> >> index 17c1042b2df8..2f7aad71b3c9 100644
> >> --- a/Documentation/devicetree/bindings/serial/atmel-usart.txt
> >> +++ b/Documentation/devicetree/bindings/serial/atmel-usart.txt
> >> @@ -35,7 +35,7 @@ Example:
> >>  		clock-names = "usart";
> >>  		atmel,use-dma-rx;
> >>  		atmel,use-dma-tx;
> >> -		rts-gpios = <&pioD 15 0>;
> >> +		rts-gpios = <&pioD 15 GPIO_ACTIVE_LOW>;
> > 
> > I was told we should not use macros here. If it is still the truth:
> > 
> > rts-gpios = <&pioD 15 1>;
> 
> But I'd really like to know if macros are forbidden in DT documentation and why...
> Because, IMHO, <&pioD 15 1> talks less that <&pioD 15 GPIO_ACTIVE_LOW>.
> Which is a shame in a documentation.

I don't remember who told me that but the reason was that device tree
should not depend on Linux and macros are relative to Linux.

> 
> Rob, any idea on that ?
> 
> (actually, I missed some uses of GPIO_ACTIVE_ macros in Documentation :)
> git grep GPIO_ACTIVE Documentation/devicetree/bindings/
> Documentation/devicetree/bindings/gpio/gpio-davinci.txt:                gpios = <&gpio 10 GPIO_ACTIVE_HIGH>;
> Documentation/devicetree/bindings/gpio/gpio-davinci.txt:                gpios = <&gpio 11 GPIO_ACTIVE_HIGH>;
> Documentation/devicetree/bindings/gpio/gpio-lp3943.txt:         gpios = <&gpioex 9 GPIO_ACTIVE_LOW>;
> Documentation/devicetree/bindings/gpio/gpio-lp3943.txt:         gpios = <&gpioex 10 GPIO_ACTIVE_LOW>;
> Documentation/devicetree/bindings/gpio/gpio-pcf857x.txt:    GPIO_ACTIVE_HIGH and GPIO_ACTIVE_LOW flags are supported.
> Documentation/devicetree/bindings/gpio/gpio-tz1090-pdc.txt:      GPIO_ACTIVE_HIGH
> Documentation/devicetree/bindings/gpio/gpio-tz1090-pdc.txt:      GPIO_ACTIVE_LOW
> Documentation/devicetree/bindings/gpio/gpio-tz1090.txt:        GPIO_ACTIVE_HIGH
> Documentation/devicetree/bindings/gpio/gpio-tz1090.txt:        GPIO_ACTIVE_LOW
> Documentation/devicetree/bindings/gpio/renesas,gpio-rcar.txt:    GPIO_ACTIVE_HIGH and GPIO_ACTIVE_LOW flags are supported.
> Documentation/devicetree/bindings/input/gpio-beeper.txt:                gpios = <&gpio3 23 GPIO_ACTIVE_HIGH>;
> Documentation/devicetree/bindings/mmc/mmc.txt:also be specified using the OF_GPIO_ACTIVE_LOW flag. This creates an ambiguity
> Documentation/devicetree/bindings/mmc/mmc.txt:OF_GPIO_ACTIVE_LOW flag clear and specifying the respective *-inverted
> Documentation/devicetree/bindings/net/nfc/trf7970a.txt:         ti,enable-gpios = <&gpio2 2 GPIO_ACTIVE_LOW>,
> Documentation/devicetree/bindings/net/nfc/trf7970a.txt:                           <&gpio2 5 GPIO_ACTIVE_LOW>;
> Documentation/devicetree/bindings/net/wireless/ti,wl1251.txt:           ti,power-gpio = <&gpio3 23 GPIO_ACTIVE_HIGH>; /* 87 */
> Documentation/devicetree/bindings/pinctrl/renesas,pfc-pinctrl.txt:    GPIO_ACTIVE_HIGH and GPIO_ACTIVE_LOW flags are supported.
> Documentation/devicetree/bindings/pinctrl/renesas,pfc-pinctrl.txt:                      gpios = <&pfc 20 GPIO_ACTIVE_LOW>;
> Documentation/devicetree/bindings/power/isp1704.txt:    nxp,enable-gpio = <&gpio3 3 GPIO_ACTIVE_LOW>;
> Documentation/devicetree/bindings/sound/max98090.txt:   interrupts = <TEGRA_GPIO(H, 4) GPIO_ACTIVE_HIGH>;
> Documentation/devicetree/bindings/sound/rt5640.txt:     interrupts = <TEGRA_GPIO(W, 3) GPIO_ACTIVE_HIGH>;
> Documentation/devicetree/bindings/sound/rt5640.txt:             <&gpio TEGRA_GPIO(V, 3) GPIO_ACTIVE_HIGH>;
> Documentation/devicetree/bindings/sound/tpa6130a2.txt:  power-gpio = <&gpio4 2 GPIO_ACTIVE_HIGH>;
> Documentation/devicetree/bindings/usb/usb-nop-xceiv.txt:                reset-gpios = <&gpio1 7 GPIO_ACTIVE_LOW>;
> Documentation/devicetree/bindings/video/backlight/gpio-backlight.txt:           gpios = <&gpio3 4 GPIO_ACTIVE_HIGH>;
> Documentation/devicetree/bindings/video/panel-dsi-cm.txt:       reset-gpios = <&gpio4 6 GPIO_ACTIVE_HIGH>;
> Documentation/devicetree/bindings/video/sony,acx565akm.txt:     reset-gpios = <&gpio3 26 GPIO_ACTIVE_HIGH>; /* 90 */
> Documentation/devicetree/bindings/video/ti,omap-dss.txt:                gpios = <&gpio1 0 GPIO_ACTIVE_LOW>;     /* 0, power-down */
> Documentation/devicetree/bindings/video/ti,omap-dss.txt:                gpios = <&gpio2 28 GPIO_ACTIVE_HIGH>,   /* 60, CT CP HPD */
> Documentation/devicetree/bindings/video/ti,omap-dss.txt:                        <&gpio2 9 GPIO_ACTIVE_HIGH>,    /* 41, LS OE */
> Documentation/devicetree/bindings/video/ti,omap-dss.txt:                        <&gpio2 31 GPIO_ACTIVE_HIGH>;   /* 63, HPD */
> Documentation/devicetree/bindings/video/ti,tfp410.txt:  powerdown-gpios = <&twl_gpio 2 GPIO_ACTIVE_LOW>;
> Documentation/devicetree/bindings/video/ti,tpd12s015.txt:       gpios = <&gpio2 28 GPIO_ACTIVE_HIGH>,   /* 60, CT CP HPD */
> Documentation/devicetree/bindings/video/ti,tpd12s015.txt:               <&gpio2 9 GPIO_ACTIVE_HIGH>,    /* 41, LS OE */
> Documentation/devicetree/bindings/video/ti,tpd12s015.txt:               <&gpio2 31 GPIO_ACTIVE_HIGH>;   /* 63, HPD */
> Documentation/devicetree/bindings/watchdog/gpio-wdt.txt:                gpios = <&gpio3 9 GPIO_ACTIVE_LOW>;
> 
> Richard.
> 
> 
> _______________________________________________
> linux-arm-kernel mailing list
> linux-arm-kernel@lists.infradead.org
> http://lists.infradead.org/mailman/listinfo/linux-arm-kernel
Richard Genoud April 15, 2014, 8:12 a.m. UTC | #5
On 15/04/2014 10:00, Ludovic Desroches wrote:
> On Tue, Apr 15, 2014 at 09:39:59AM +0200, Richard Genoud wrote:
>> On 14/04/2014 17:22, Ludovic Desroches wrote:
>>> Hi Richard,
>>>
>>> On Mon, Apr 14, 2014 at 04:58:02PM +0200, Richard Genoud wrote:
>>>> RTS pin is an active low pin.
>>>> For now, this doesn't change anything as the ACTIVE_LOW flag is not
>>>> handled in atmel_serial, but it will be in 3.16.
>>>>
>>>> Signed-off-by: Richard Genoud <richard.genoud@gmail.com>
>>>> ---
>>>>  Documentation/devicetree/bindings/serial/atmel-usart.txt | 2 +-
>>>>  1 file changed, 1 insertion(+), 1 deletion(-)
>>>>
>>>> diff --git a/Documentation/devicetree/bindings/serial/atmel-usart.txt b/Documentation/devicetree/bindings/serial/atmel-usart.txt
>>>> index 17c1042b2df8..2f7aad71b3c9 100644
>>>> --- a/Documentation/devicetree/bindings/serial/atmel-usart.txt
>>>> +++ b/Documentation/devicetree/bindings/serial/atmel-usart.txt
>>>> @@ -35,7 +35,7 @@ Example:
>>>>  		clock-names = "usart";
>>>>  		atmel,use-dma-rx;
>>>>  		atmel,use-dma-tx;
>>>> -		rts-gpios = <&pioD 15 0>;
>>>> +		rts-gpios = <&pioD 15 GPIO_ACTIVE_LOW>;
>>>
>>> I was told we should not use macros here. If it is still the truth:
>>>
>>> rts-gpios = <&pioD 15 1>;
>>
>> But I'd really like to know if macros are forbidden in DT documentation and why...
>> Because, IMHO, <&pioD 15 1> talks less that <&pioD 15 GPIO_ACTIVE_LOW>.
>> Which is a shame in a documentation.
> 
> I don't remember who told me that but the reason was that device tree
> should not depend on Linux and macros are relative to Linux.
> 
Well, that makes sense, but I thought that include/dt-bindings/ was more
DT relative.
Linus Walleij April 22, 2014, 6:42 p.m. UTC | #6
On Tue, Apr 15, 2014 at 10:00 AM, Ludovic Desroches
<ludovic.desroches@atmel.com> wrote:
> On Tue, Apr 15, 2014 at 09:39:59AM +0200, Richard Genoud wrote:
>> On 14/04/2014 17:22, Ludovic Desroches wrote:
>> > Hi Richard,
>> >
>> > On Mon, Apr 14, 2014 at 04:58:02PM +0200, Richard Genoud wrote:
>> >> RTS pin is an active low pin.
>> >> For now, this doesn't change anything as the ACTIVE_LOW flag is not
>> >> handled in atmel_serial, but it will be in 3.16.
>> >>
>> >> Signed-off-by: Richard Genoud <richard.genoud@gmail.com>
>> >> ---
>> >>  Documentation/devicetree/bindings/serial/atmel-usart.txt | 2 +-
>> >>  1 file changed, 1 insertion(+), 1 deletion(-)
>> >>
>> >> diff --git a/Documentation/devicetree/bindings/serial/atmel-usart.txt b/Documentation/devicetree/bindings/serial/atmel-usart.txt
>> >> index 17c1042b2df8..2f7aad71b3c9 100644
>> >> --- a/Documentation/devicetree/bindings/serial/atmel-usart.txt
>> >> +++ b/Documentation/devicetree/bindings/serial/atmel-usart.txt
>> >> @@ -35,7 +35,7 @@ Example:
>> >>            clock-names = "usart";
>> >>            atmel,use-dma-rx;
>> >>            atmel,use-dma-tx;
>> >> -          rts-gpios = <&pioD 15 0>;
>> >> +          rts-gpios = <&pioD 15 GPIO_ACTIVE_LOW>;
>> >
>> > I was told we should not use macros here. If it is still the truth:
>> >
>> > rts-gpios = <&pioD 15 1>;
>>
>> But I'd really like to know if macros are forbidden in DT documentation and why...
>> Because, IMHO, <&pioD 15 1> talks less that <&pioD 15 GPIO_ACTIVE_LOW>.
>> Which is a shame in a documentation.
>
> I don't remember who told me that but the reason was that device tree
> should not depend on Linux and macros are relative to Linux.

These macros are not Linux-specific.

They come from include/dt-bindings/* which is part of the OS-neutral
bindings, just in a machine-readable form.

Yours,
Linus Walleij
Richard Genoud April 23, 2014, 8:18 a.m. UTC | #7
2014-04-22 20:42 GMT+02:00 Linus Walleij <linus.walleij@linaro.org>:
> On Tue, Apr 15, 2014 at 10:00 AM, Ludovic Desroches
> <ludovic.desroches@atmel.com> wrote:
>> On Tue, Apr 15, 2014 at 09:39:59AM +0200, Richard Genoud wrote:
>>> On 14/04/2014 17:22, Ludovic Desroches wrote:
>>> > Hi Richard,
>>> >
>>> > On Mon, Apr 14, 2014 at 04:58:02PM +0200, Richard Genoud wrote:
>>> >> RTS pin is an active low pin.
>>> >> For now, this doesn't change anything as the ACTIVE_LOW flag is not
>>> >> handled in atmel_serial, but it will be in 3.16.
>>> >>
>>> >> Signed-off-by: Richard Genoud <richard.genoud@gmail.com>
>>> >> ---
>>> >>  Documentation/devicetree/bindings/serial/atmel-usart.txt | 2 +-
>>> >>  1 file changed, 1 insertion(+), 1 deletion(-)
>>> >>
>>> >> diff --git a/Documentation/devicetree/bindings/serial/atmel-usart.txt b/Documentation/devicetree/bindings/serial/atmel-usart.txt
>>> >> index 17c1042b2df8..2f7aad71b3c9 100644
>>> >> --- a/Documentation/devicetree/bindings/serial/atmel-usart.txt
>>> >> +++ b/Documentation/devicetree/bindings/serial/atmel-usart.txt
>>> >> @@ -35,7 +35,7 @@ Example:
>>> >>            clock-names = "usart";
>>> >>            atmel,use-dma-rx;
>>> >>            atmel,use-dma-tx;
>>> >> -          rts-gpios = <&pioD 15 0>;
>>> >> +          rts-gpios = <&pioD 15 GPIO_ACTIVE_LOW>;
>>> >
>>> > I was told we should not use macros here. If it is still the truth:
>>> >
>>> > rts-gpios = <&pioD 15 1>;
>>>
>>> But I'd really like to know if macros are forbidden in DT documentation and why...
>>> Because, IMHO, <&pioD 15 1> talks less that <&pioD 15 GPIO_ACTIVE_LOW>.
>>> Which is a shame in a documentation.
>>
>> I don't remember who told me that but the reason was that device tree
>> should not depend on Linux and macros are relative to Linux.
>
> These macros are not Linux-specific.
>
> They come from include/dt-bindings/* which is part of the OS-neutral
> bindings, just in a machine-readable form.

Thanks for this clarification !

Richard.
diff mbox

Patch

diff --git a/Documentation/devicetree/bindings/serial/atmel-usart.txt b/Documentation/devicetree/bindings/serial/atmel-usart.txt
index 17c1042b2df8..2f7aad71b3c9 100644
--- a/Documentation/devicetree/bindings/serial/atmel-usart.txt
+++ b/Documentation/devicetree/bindings/serial/atmel-usart.txt
@@ -35,7 +35,7 @@  Example:
 		clock-names = "usart";
 		atmel,use-dma-rx;
 		atmel,use-dma-tx;
-		rts-gpios = <&pioD 15 0>;
+		rts-gpios = <&pioD 15 GPIO_ACTIVE_LOW>;
 	};
 
 - use DMA: