Re: [PATCH v2 1/7] mfd: add atmel-hlcdc driver

[Boris BREZILLON <boris.brezillon@free-electrons.com>]

On 16/06/2014 19:03, Lee Jones wrote:
> On Mon, 16 Jun 2014, Boris BREZILLON wrote:
>> On 16/06/2014 14:50, Lee Jones wrote:
>>>> The HLCDC IP available on some Atmel SoCs (i.e. at91sam9n12, at91sam9x5
>>>> family or sama5d3 family) exposes 2 subdevices:
>>>> - a display controller (controlled by a DRM driver)
>>>> - a PWM chip
>>>>
>>>> Add support for the MFD device which will just retrieve HLCDC clocks and
>>>> create a regmap so that subdevices can access the HLCDC register range
>>>> concurrently.
>>>>
>>>> Signed-off-by: Boris BREZILLON <boris.brezillon@free-electrons.com>
>>>> ---
>>>>  .../devicetree/bindings/mfd/atmel-hlcdc.txt        |  41 ++++++++
>>>>  drivers/mfd/Kconfig                                |  11 ++
>>>>  drivers/mfd/Makefile                               |   1 +
>>>>  drivers/mfd/atmel-hlcdc.c                          | 116 +++++++++++++++++++++
>>>>  include/linux/mfd/atmel-hlcdc.h                    |  78 ++++++++++++++
>>>>  5 files changed, 247 insertions(+)
>>>>  create mode 100644 Documentation/devicetree/bindings/mfd/atmel-hlcdc.txt
>>>>  create mode 100644 drivers/mfd/atmel-hlcdc.c
>>>>  create mode 100644 include/linux/mfd/atmel-hlcdc.h
>>>> diff --git a/Documentation/devicetree/bindings/mfd/atmel-hlcdc.txt b/Documentation/devicetree/bindings/mfd/atmel-hlcdc.txt
>>>> new file mode 100644
>>>> index 0000000..f5b69cb
>>>> --- /dev/null
>>>> +++ b/Documentation/devicetree/bindings/mfd/atmel-hlcdc.txt
> [...]
>
>>>> +		hlcdc-display-controller {
>>>> +			compatible = "atmel,hlcdc-dc";
>>>> +			interrupts = <36 IRQ_TYPE_LEVEL_HIGH 0>;
>>> I assume you're using the 3rd parameter for flags.  If so, please use
>>> the defines.
>> No, the third parameter encodes the irq priority (from 0 to 7 IIRC).
> Ah okay.  Can you point me to the documentation for this IRQ
> controller please?  I'd like to have a quick peek.  It might be worth
> defining the priority to prevent confusion, also you definitely should
> document it in your binding.

Here's Atmel's irq chip DT bindings documentation:

http://lxr.free-electrons.com/source/Documentation/devicetree/bindings/arm/atmel-aic.txt

I'll describe interrupt fields in the HLCDC DT bindings doc.



>
> [...]
>
>>>> +static struct platform_driver atmel_hlcdc_driver = {
>>>> +	.probe = atmel_hlcdc_probe,
>>>> +	.remove = atmel_hlcdc_remove,
>>>> +	.driver = {
>>>> +		.name = "atmel-hlcdc",
>>>> +		.owner = THIS_MODULE,
>>>> +		.of_match_table = atmel_hlcdc_match,
>>> Is this driver DT only?
>> Yes it is.
> So it should depend on OF in the Kconfig entry.
>
Absolutely, I'll add the dependency.

Thanks,

Boris

-- 
Boris Brezillon, Free Electrons
Embedded Linux and Kernel engineering
http://free-electrons.com