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Date:   Sun, 1 Sep 2019 19:23:23 +0200
From:   Pavel Machek <pavel@ucw.cz>
To:     Akinobu Mita <akinobu.mita@gmail.com>
Cc:     linux-leds@vger.kernel.org, linux-kernel@vger.kernel.org,
        Jacek Anaszewski <jacek.anaszewski@gmail.com>,
        Dan Murphy <dmurphy@ti.com>
Subject: Re: [PATCH] leds: remove PAGE_SIZE limit of
 /sys/class/leds/<led>/trigger
Message-ID: <20190901172323.GB1005@bug>
References: <1567090164-6819-1-git-send-email-akinobu.mita@gmail.com>
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Hi!

> Reading /sys/class/leds/<led>/trigger returns all available LED triggers.
> However, the size of this file is limited to PAGE_SIZE because of the
> limitation for sysfs attribute.
> 
> Enabling LED CPU trigger on systems with thousands of CPUs easily hits
> PAGE_SIZE limit, and makes it impossible to see all available LED triggers
> and which trigger is currently activated.
> 
> This converts /sys/class/leds/<led>/trigger to bin attribute and removes
> the PAGE_SIZE limitation.
> 
> Cc: Jacek Anaszewski <jacek.anaszewski@gmail.com>

Nothing obviously wrong from a quick look...

Acked-by: Pavel Machek <pavel@ucw.cz>

Thanks a lot for doing this!

I believe we should cc Greg here.

BTW if you care about cpuled trigger... it would be cool to turn it into one trigger and pass
a cpu number as a parameter. It is good to see this limit fixed, but real solution is to
register one trigger per driver.

Best regards,
										Pavel

-- 
(english) http://www.livejournal.com/~pavelmachek
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