From mboxrd@z Thu Jan 1 00:00:00 1970 From: Stas Sergeev Subject: Re: [PATCH v2 0/3] leds: blink resolution improvements Date: Tue, 28 Apr 2015 13:12:15 +0300 Message-ID: <553F5CFF.9090601@list.ru> References: <553E6CF5.4030601@list.ru> <553F4B60.20204@samsung.com> Mime-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: QUOTED-PRINTABLE Return-path: Received: from smtp34.i.mail.ru ([94.100.177.94]:53480 "EHLO smtp34.i.mail.ru" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S933106AbbD1KMb (ORCPT ); Tue, 28 Apr 2015 06:12:31 -0400 In-Reply-To: <553F4B60.20204@samsung.com> Sender: linux-leds-owner@vger.kernel.org List-Id: linux-leds@vger.kernel.org To: Jacek Anaszewski Cc: linux-leds@vger.kernel.org, Linux kernel , Stas Sergeev 28.04.2015 11:57, Jacek Anaszewski =D0=BF=D0=B8=D1=88=D0=B5=D1=82: > Hi Stas, >=20 > 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.