Re: [PATCH 1/4] dt-bindings: sc16is7xx: Add flag to activate IrDA mode

[Maarten Brock <m.brock@vanmierlo.com>]

On 2020-05-18 20:41, Daniel Mack wrote:
> On 5/18/20 8:08 PM, Rob Herring wrote:
>> On Fri, May 08, 2020 at 04:37:54PM +0200, Daniel Mack wrote:
>>> From: Pascal Huerst <pascal.huerst@gmail.com>
>>> 
>>> This series of uart controllers is able to work in IrDA mode.
>>> This adds a flag to the device tree to enable that feature if needed.
>>> 
>>> Signed-off-by: Pascal Huerst <pascal.huerst@gmail.com>
>>> ---
>>>  Documentation/devicetree/bindings/serial/nxp,sc16is7xx.txt | 4 ++++
>>>  1 file changed, 4 insertions(+)
>>> 
>>> diff --git 
>>> a/Documentation/devicetree/bindings/serial/nxp,sc16is7xx.txt 
>>> b/Documentation/devicetree/bindings/serial/nxp,sc16is7xx.txt
>>> index c1091a923a89..9317c320c82c 100644
>>> --- a/Documentation/devicetree/bindings/serial/nxp,sc16is7xx.txt
>>> +++ b/Documentation/devicetree/bindings/serial/nxp,sc16is7xx.txt
>>> @@ -21,6 +21,8 @@ Optional properties:
>>>    the second cell is used to specify the GPIO polarity:
>>>      0 = active high,
>>>      1 = active low.
>>> +- linux,irda-mode-port-0: Use IrDA mode on port #0
>>> +- linux,irda-mode-port-1: Use IrDA mode on port #1 (for dual-port 
>>> devices only)
>>> 
>>>  Example:
>>>          sc16is750: sc16is750@51 {
>>> @@ -55,6 +57,8 @@ Optional properties:
>>>    the second cell is used to specify the GPIO polarity:
>>>      0 = active high,
>>>      1 = active low.
>>> +- linux,irda-mode-port-0: Use IrDA mode on port #0
>>> +- linux,irda-mode-port-1: Use IrDA mode on port #1 (for dual-port 
>>> devices only)
>> 
>> How about an array of 1 or 2 entries instead?

I like this idea.

> Yes, that would be an alternative. We just weren't sure what type the
> elements of the array would have. Could you point to an existing 
> example?

I think you need device_property_read_u8_array(). I can only find
device_property_read_u32_array() used in the serial drivers tree in 
serial_core.c,
but that should be similar.

Maarten