Message-ID: <553F5CFF.9090601@list.ru>
Date: Tue, 28 Apr 2015 13:12:15 +0300
From: Stas Sergeev <stsp@list.ru>
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To: Jacek Anaszewski <j.anaszewski@samsung.com>
CC: linux-leds@vger.kernel.org, Linux kernel <linux-kernel@vger.kernel.org>,
        Stas Sergeev <stsp@users.sourceforge.net>
Subject: Re: [PATCH v2 0/3] leds: blink resolution improvements
References: <553E6CF5.4030601@list.ru> <553F4B60.20204@samsung.com>
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28.04.2015 11:57, Jacek Anaszewski пишет:
> Hi Stas,
> 
> Have you tested it?
Of course I did.
Works with gpio driver and provides up to 10usec precision on
armada-xp board.
This is 1000 times better than without my patch - the precision
was 10ms (jiffy).

> I tried it with Samsung M0 board and
> my leds-aat1290 driver. It didn't work well. And for small delay
> intervals it will not have a chance to work reliably with all drivers,
> especially the ones which use mutex in their brightness_set op,
> since mutex can sleep.
OK, I can remove the nsec resolution.
I added it for the future, it doesn't work for me either, but
hrtimer has an API for it, so I thought it may work on another hw.
I don't see why it can't stay, but if it bothers you that much,
I'll remove it.

> I am afraid that we have to stay with what we have currently.
This is a counter-productive conclusion.
My patch does 1000 times precision improvement with gpio driver.
If you only want nsec to be removed as it doesn't work - that's
fine with me.
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