Re: [PATCH 4/7] [media] ir-rx51: add DT support to driver

[Ivaylo Dimitrov <ivo.g.dimitrov.75@gmail.com>]

On 10.05.2016 00:07, Rob Herring wrote:
> On Mon, May 9, 2016 at 3:53 PM, Ivaylo Dimitrov
> <ivo.g.dimitrov.75@gmail.com> wrote:
>> Hi,
>>
>> On  9.05.2016 23:06, Rob Herring wrote:
>>>
>>> On Sat, May 07, 2016 at 06:21:45PM +0300, Ivaylo Dimitrov wrote:
>>>>
>>>> With the upcoming removal of legacy boot, lets add support to one of the
>>>> last N900 drivers remaining without it. As the driver still uses omap
>>>> dmtimer, add auxdata as well.
>>>>
>>>> Signed-off-by: Ivaylo Dimitrov <ivo.g.dimitrov.75@gmail.com>
>>>> ---
>>>>    .../devicetree/bindings/media/nokia,lirc-rx51         | 19
>>>> +++++++++++++++++++
>>>>    arch/arm/mach-omap2/pdata-quirks.c                    |  6 +-----
>>>>    drivers/media/rc/ir-rx51.c                            | 11 ++++++++++-
>>>>    3 files changed, 30 insertions(+), 6 deletions(-)
>>>>    create mode 100644
>>>> Documentation/devicetree/bindings/media/nokia,lirc-rx51
>>>>
>>>> diff --git a/Documentation/devicetree/bindings/media/nokia,lirc-rx51
>>>> b/Documentation/devicetree/bindings/media/nokia,lirc-rx51
>>>> new file mode 100644
>>>> index 0000000..5b3081e
>>>> --- /dev/null
>>>> +++ b/Documentation/devicetree/bindings/media/nokia,lirc-rx51
>>>> @@ -0,0 +1,19 @@
>>>> +Device-Tree bindings for LIRC TX driver for Nokia N900(RX51)
>>>> +
>>>> +Required properties:
>>>> +       - compatible: should be "nokia,lirc-rx51".
>>>
>>>
>>> lirc is a Linux term. Also, nokia,rx51-... would be conventional
>>> ordering.
>>>
>>
>> I used the driver name ("lirc_rx51") to not bring confusion. Also, it
>> registers itself through lirc_register_driver() call, so having lirc in its
>> name somehow makes sense.
>>
>> I am not very good in inventing names, the best compatible I can think of is
>> "nokia,rx51-ir". Is that ok?
>
> Sure, but...
>
>>> Is this anything more than a PWM LED?
>>>
>>
>> It is an IR LED connected through a driver to McSPI2_SIMO pin of OMAP3,
>> which pin can be configured as PWM or GPIO(there are other configurations,
>> but they don't make sense). In theory it could be used for various things
>> (like uni-directional serial TX, or stuff like that), but in practice it
>> allows N900 to be act as an IR remote controller. I guess that fits in
>> "nothing more than a PWM LED", more or less.
>
> There's already a pwm-led binding that can be used. Though there may
> be missing consumer IR to LED subsystem support in the kernel. You
> could list both compatibles, use the rx51 IR driver now, and then move
> to pwm-led driver in the future.
>

I looked at the pwm-leds (and related) code and couldn't see how it will 
do the job of controlling IR TX LED as a remote controller. So yeah, it 
seems CIR support in LEDS subsystem is non existent.

Could you elaborate on "list both compatibles", I don't really 
understand what I should do.

Ivo