[PATCH linux dev-4.10 v6 1/2] ARM: dts: aspeed: Witherspoon add gpio-keys-polled for fan presence

[Cédric Le Goater]

On 08/02/2017 04:33 AM, Christopher Bostic wrote:
> 
> 
> On 7/31/17 2:48 AM, Cédric Le Goater wrote:
>> On 07/29/2017 08:36 PM, Christopher Bostic wrote:
>>> Add gpio-keys-polled  node for pca955x fan presence lines.
>>> Add GPIO details to pca955x for the presence lines as well.
>>>
>>> Polling period of 1 second determined to be the max acceptable
>>> value based on discussions with Brad Bishop and Matt Spinler.
>>> Tested with gpiomon program - verified.
>>>
>>> Signed-off-by: Christopher Bostic <cbostic at linux.vnet.ibm.com>
>>> ---
>>> v6 - Add gpio pin details for fan presence to pca955x node
>>> v5 - Fix gpio-keys-polled driver probe errors.  Missing pca955x
>>>       gpio cells property and wrong format for poll-interval.
>>> v4 - Add details regarding polling period to commit message.
>>> v3 - Remove 'autorepeat'
>>>     - Increase polling period to 1 second.
>>>     - Remove GPIO specifiers from pca955x in dev tree
>>> v2 - Change 'linux,code' from a unique global value to a local one
>>>       for all the gpio-keys-polled devices.
>>> ---
>>>   arch/arm/boot/dts/aspeed-bmc-opp-witherspoon.dts | 52 ++++++++++++++++++++++++
>>>   1 file changed, 52 insertions(+)
>>>
>>> diff --git a/arch/arm/boot/dts/aspeed-bmc-opp-witherspoon.dts b/arch/arm/boot/dts/aspeed-bmc-opp-witherspoon.dts
>>> index 5afc03a..70328668 100644
>>> --- a/arch/arm/boot/dts/aspeed-bmc-opp-witherspoon.dts
>>> +++ b/arch/arm/boot/dts/aspeed-bmc-opp-witherspoon.dts
>>> @@ -56,6 +56,37 @@
>>>           };
>>>       };
>>>   +    gpio-keys-polled {
>>> +        compatible = "gpio-keys-polled";
>>> +        #address-cells = <1>;
>>> +        #size-cells = <0>;
>>> +        poll-interval = <1000>;
>>> +
>>> +        fan0-presence {
>>> +            label = "fan0-presence";
>>> +            gpios = <&pca0 4 GPIO_ACTIVE_LOW>;
>>> +            linux,code = <4>;
>>> +        };
>>> +
>>> +        fan1-presence {
>>> +            label = "fan1-presence";
>>> +            gpios = <&pca0 5 GPIO_ACTIVE_LOW>;
>>> +            linux,code = <5>;
>>> +        };
>>> +
>>> +        fan2-presence {
>>> +            label = "fan2-presence";
>>> +            gpios = <&pca0 6 GPIO_ACTIVE_LOW>;
>>> +            linux,code = <6>;
>>> +        };
>>> +
>>> +        fan3-presence {
>>> +            label = "fan3-presence";
>>> +            gpios = <&pca0 7 GPIO_ACTIVE_LOW>;
>>> +            linux,code = <7>;
>>> +        };
>>> +    };
>>> +
>>>       leds {
>>>           compatible = "gpio-leds";
>>>   @@ -277,6 +308,7 @@
>>>           reg = <0x60>;
>>>           #address-cells = <1>;
>>>           #size-cells = <0>;
>>> +        #gpio-cells = <2>;
>> you should also add a :
>>
>>         gpio-controller;
>>
>> if you want to use the lines as GPIOs
>>
>> C.
> Hi Cedric,
> 
> If I add 'gpio-controller' here are you indicating that would not 
> require any modifications I made to the leds-pca955x.c file?  

yes.

> I've tried that and found I still need that leds-pca955x.c change 
> even if I add 'gpio-controller' attribute to get gpio-keys-polled 
>  device driver to properly probe the pca955x lines.

OK. I will give it a try on a QEMU. Maybe there are some incompatibilities 
with the gpio-keys driver bindings

C.

> Thanks
> Chris
> 
>>>             fan0: led at 0 {
>>>               label = "fan0";
>>> @@ -302,6 +334,26 @@
>>>               reg = <3>;
>>>               type = <PCA955X_TYPE_LED>;
>>>           };
>>> +        fan0_pres_gpio: gpio at 4 {
>>> +            label = "fan0_presence";
>>> +            reg = <4>;
>>> +            type = <PCA955X_TYPE_GPIO>;
>>> +        };
>>> +        fan1_pres_gpio: gpio at 5 {
>>> +            label = "fan1_presence";
>>> +            reg = <5>;
>>> +            type = <PCA955X_TYPE_GPIO>;
>>> +        };
>>> +        fan2_pres_gpio: gpio at 6 {
>>> +            label = "fan2_presence";
>>> +            reg = <6>;
>>> +            type = <PCA955X_TYPE_GPIO>;
>>> +        };
>>> +        fan3_pres_gpio: gpio at 7 {
>>> +            label = "fan3_presence";
>>> +            reg = <7>;
>>> +            type = <PCA955X_TYPE_GPIO>;
>>> +        };
>>>           front_fault: led at 13 {
>>>               label = "front-fault";
>>>               default-state = "keep";
>>>
>