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Date: Thu, 07 Aug 2014 09:49:49 +0200
From: Javier Martinez Canillas <javier.martinez@collabora.co.uk>
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To: Dmitry Torokhov <dmitry.torokhov@gmail.com>
CC: Tomasz Figa <tomasz.figa@gmail.com>, Nick Dyer <nick.dyer@itdev.co.uk>,
        Stephen Warren <swarren@nvidia.com>,
        Yufeng Shen <miletus@chromium.org>, Benson Leung <bleung@chromium.org>,
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        linux-input@vger.kernel.org, devicetree@vger.kernel.org,
        linux-samsung-soc@vger.kernel.org, linux-kernel@vger.kernel.org
Subject: Re: [PATCH 1/2] Input: atmel_mxt_ts - Get IRQ edge/level flags on
 DT booting
References: <1407372486-25881-1-git-send-email-javier.martinez@collabora.co.uk> <53E2D2F8.7010606@gmail.com> <53E2DAAC.1060602@collabora.co.uk> <20140807060926.GA651@core.coreip.homeip.net>
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Hello Dmitry,

On 08/07/2014 08:09 AM, Dmitry Torokhov wrote:
>> 
>> > irq_of_parse_and_map() already sets up IRQ trigger type based on DT
>> > data, by calling irq_create_of_mapping() which in turn calls
>> > irq_set_irq_type().
>> >
>> 
>> Right but somehow when the IRQ is actually requested the type is overwritten by
>> the value passed to request_threaded_irq() and interrupts are not being
>> generated by the device without this patch.
>> 
>> Do you think that this is a bug in the "interrupt-parent" irqchip driver or the
>> IRQ core? I'm not that familiar with the IRQ subsystem.
> 
> No, this is clearly driver fault - it smashed previously done setup with new
> flags.
>

Thanks a lot for the clarification. That was my understanding as well but wanted
to be sure.

>> > 
>> > It might be a bit cleaner to just assign the flags to pdata->irqflags in
>> > mxt_parse_dt() instead. That would also account for the fact that pdata,
>> > if provided, should have priority over DT.
>> > 
>> 
>> You are totally right, also this will break if CONFIG_OF is not enabled since
>> dev.of_node will not be defined. While this already is taken into account for
>> mxt_parse_dt() by defining an empty function.
>> 
>> I'll change it in v2 if getting the flags from the driver is the right approach
> 
> Yes, please.
> 

Just posted a v2 [0] with Tomasz suggestion and the patch is indeed a lot cleaner.

Best regards,
Javier

[0]: https://lkml.org/lkml/2014/8/7/82