From mboxrd@z Thu Jan 1 00:00:00 1970 From: Uwe =?iso-8859-1?Q?Kleine-K=F6nig?= Date: Thu, 02 Jul 2015 07:42:43 +0000 Subject: Re: [RFC PATCH 00/15] pwm: add support for atomic update Message-Id: <20150702074243.GE11824@pengutronix.de> List-Id: References: <1435738921-25027-1-git-send-email-boris.brezillon@free-electrons.com> <20150702070343.GD11824@pengutronix.de> <5594E56C.3010908@ti.com> In-Reply-To: <5594E56C.3010908@ti.com> MIME-Version: 1.0 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable To: linux-arm-kernel@lists.infradead.org On Thu, Jul 02, 2015 at 10:17:00AM +0300, Tomi Valkeinen wrote: >=20 >=20 > On 02/07/15 10:03, Uwe Kleine-K=F6nig wrote: > > Hello Boris, > >=20 > > On Wed, Jul 01, 2015 at 10:21:46AM +0200, Boris Brezillon wrote: > >> This series adds support for atomic PWM update, or ITO, the capability > >> to update all the parameters of a PWM device (enabled/disabled, period, > >> duty and polarity) in one go. > > on first reading the subject of your series I thought it was about > > asserting that the newly set config is active before the call to > > pwm_config (et al) returns. That's a problem I addressed a few times in > > the past. I wonder if it's only me or if a different wording should be > > used for "update all parameters with a single function call". >=20 > In my vocabulary "blocking" means that the work is done before the > function returns, and "atomic" means the work is done in one step. blocking is IMHO something slightly different, maybe "synchronous" is a good term for "done when the call returns". For write(2) I'd say - blocking means to only return when the write request has reached the kernel, but not necessarily the medium. I.e. the caller doesn't need to care further; and - atomic means that the contents of two concurrent writers don't mix in the resulting file content; and - synchronous means that once write() returns the data is on the medium. So atomic seems to be fine to use here. Best regards Uwe --=20 Pengutronix e.K. | Uwe Kleine-K=F6nig | Industrial Linux Solutions | http://www.pengutronix.de/ |