[PATCH 3/4] include: dt-bindings: Add more GPIO bank and index definition for rockchip pinctrl
Andy Yan
andy.yan at rock-chips.com
Tue Sep 6 02:33:53 PDT 2016
Hi Heiko:
On 2016年09月06日 06:10, Heiko Stuebner wrote:
> Am Montag, 5. September 2016, 18:22:46 CEST schrieb Andy Yan:
>> Hi Heiko:
>>
>> On 2016年09月05日 17:33, Heiko Stuebner wrote:
>>> Hi Andy,
>>>
>>> Am Sonntag, 4. September 2016, 16:35:30 CEST schrieb Andy Yan:
>>>> There are 8 gpio banks on RK3288, so add the missing
>>>> RK_GPIO7 and RK_GPIO8. Also add gpio index definition
>>>> to make it easier to description GPIO in dts.
>>>>
>>>> Signed-off-by: Andy Yan <andy.yan at rock-chips.com>
>>> I tend to disagree here.
>>>
>>> I consider the bank defines RK_GPIOx to be deprecated and highly
>>> discourage
>>> them being used in new boards. They only encode the same number again (2
>>> ->
>>> RK_GPIO2 etc) and therefore don't bring any useful addition over using the
>>> bank number directly.
>>>
>>> Slightly similar argument for the per-pin defines. While the external pins
>>> are described in the A/B/C/Dx notation for pinmux purposes, the gpio
>>> controllers on top use a regular 0-31 numbering. Also you cannot name
>>> constants generic GPIO_x, simply because that may conflict with other
>>> overly generic constant names.
>>>
>>> So I'm not yet convinced that these improve readability, but they would
>>> definitly need a RK_* prefix to make them specific.
>>>
>>>
>>> Heiko
>> I consider for a people who doesn't familiar with rockchip
>> pinctrl, He
>> may don't know what does these number 2/4/17....stands for in the dts
>> like
>> rockchip,pins = <2 17 RK_FUNC_GPIO &pcfg_pull_up>.
> That person shouldn't work on devicetrees anyway :-) ... or simply read the
> dt-binding for the pinctrl at first ... which should normally really be the
> first step, otherwise we wouldn't need the binding documentation.
It's true that people who wants to develop in the kernel should
know the technical detail as much as possible.
But I still thinks it's a good thing if we can write code more clearly
to let people know what it stands for at first sight.
>> But if we use meaningful macro here like : rockchip,pins =
>> <RK_GPIO2 RK_GPIO_C0 RK_FUNC_GPIO &pcfg_pull_up>, I think it easier to
>> tell people this GPIO is GPIO_C0 of BNAK2.
> I definitly don't agree for the gpio-bank number, see above .
>
>> Especially all the GPIOs in rockchip based schematic are described as
>> GPIOn_A/B/C/Dx. And it is also easier for people to directly use a macro
>> stands for 0~32 than translating A/B/C/Dx from the schematic to 0~32.
> But the pins might in fact really be helpful, but definitly need a prefix and
> maybe even distinguish between pin and gpio, aka RK_PIN_A0 etc?
>
Anyway, very glad to see you think the pin definition is helpful,
so let's move on.
I'll send a new version with the prefix as your suggested like
RK_PA/B/C/Dx.
Thanks.
> Heiko
>
>>>> ---
>>>>
>>>> include/dt-bindings/pinctrl/rockchip.h | 35
>>>>
>>>> ++++++++++++++++++++++++++++++++++ 1 file changed, 35 insertions(+)
>>>>
>>>> diff --git a/include/dt-bindings/pinctrl/rockchip.h
>>>> b/include/dt-bindings/pinctrl/rockchip.h index 743e66a..fd35350 100644
>>>> --- a/include/dt-bindings/pinctrl/rockchip.h
>>>> +++ b/include/dt-bindings/pinctrl/rockchip.h
>>>> @@ -24,6 +24,41 @@
>>>>
>>>> #define RK_GPIO3 3
>>>> #define RK_GPIO4 4
>>>> #define RK_GPIO6 6
>>>>
>>>> +#define RK_GPIO7 7
>>>> +#define RK_GPIO8 8
>>>> +
>>>> +#define GPIO_A0 0
>>>> +#define GPIO_A1 1
>>>> +#define GPIO_A2 2
>>>> +#define GPIO_A3 3
>>>> +#define GPIO_A4 4
>>>> +#define GPIO_A5 5
>>>> +#define GPIO_A6 6
>>>> +#define GPIO_A7 7
>>>> +#define GPIO_B0 8
>>>> +#define GPIO_B1 9
>>>> +#define GPIO_B2 10
>>>> +#define GPIO_B3 11
>>>> +#define GPIO_B4 12
>>>> +#define GPIO_B5 13
>>>> +#define GPIO_B6 14
>>>> +#define GPIO_B7 15
>>>> +#define GPIO_C0 16
>>>> +#define GPIO_C1 17
>>>> +#define GPIO_C2 18
>>>> +#define GPIO_C3 19
>>>> +#define GPIO_C4 20
>>>> +#define GPIO_C5 21
>>>> +#define GPIO_C6 22
>>>> +#define GPIO_C7 23
>>>> +#define GPIO_D0 24
>>>> +#define GPIO_D1 25
>>>> +#define GPIO_D2 26
>>>> +#define GPIO_D3 27
>>>> +#define GPIO_D4 28
>>>> +#define GPIO_D5 29
>>>> +#define GPIO_D6 30
>>>> +#define GPIO_D7 31
>>>>
>>>> #define RK_FUNC_GPIO 0
>>>> #define RK_FUNC_1 1
>
>
>
>
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