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Date:   Fri, 14 Apr 2023 16:12:01 +0200 (CEST)
From:   Jiri Kosina <jikos@kernel.org>
To:     Rahul Rameshbabu <rrameshbabu@nvidia.com>
cc:     Benjamin Tissoires <benjamin.tissoires@redhat.com>,
        linux-input@vger.kernel.org, linux-kernel@vger.kernel.org
Subject: Re: [PATCH v2 1/1] HID: shield: Initial driver implementation with
 Thunderstrike support
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References: <20230410170840.16119-1-rrameshbabu@nvidia.com> <20230410170840.16119-2-rrameshbabu@nvidia.com> <nycvar.YFH.7.76.2304131705350.29760@cbobk.fhfr.pm> <87a5zbhrdf.fsf@nvidia.com>
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On Fri, 14 Apr 2023, Rahul Rameshbabu wrote:

> The reason why I disable interrupts is because I call
> thunderstrike_update_haptics from the play_effect callback I pass to
> input_ff_create_memless. From there, it is used in ml_effect_timer
> drivers/input/ff-memless.c, which is a timer interrupt context so we
> should disable interrupts when taking haptics_update_lock.
> 
>   static void ml_effect_timer(struct timer_list *t)
>   {
>     struct ml_device *ml = from_timer(ml, t, timer);
>     struct input_dev *dev = ml->dev;
>     unsigned long flags;
> 
>     pr_debug("timer: updating effects\n");
> 
>     spin_lock_irqsave(&dev->event_lock, flags);
>     ml_play_effects(ml);
>     spin_unlock_irqrestore(&dev->event_lock, flags);
>   }

Ah, right, I missed that, it indeed runs in softirq context. Please 
disregard my comment.

Thanks,

-- 
Jiri Kosina
SUSE Labs