From mboxrd@z Thu Jan 1 00:00:00 1970 From: Shawn Guo Subject: Re: [PATCH v2 5/5] ARM: dts: ls1021a-tsn: Use the DSPI controller in poll mode Date: Wed, 11 Sep 2019 14:33:51 +0800 Message-ID: <20190911063350.GB17142@dragon> References: <20190822211514.19288-1-olteanv@gmail.com> <20190822211514.19288-6-olteanv@gmail.com> <20190827180502.GF23391@sirena.co.uk> <20190827181318.GG23391@sirena.co.uk> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Cc: Mark Brown , linux-spi@vger.kernel.org, lkml , devicetree@vger.kernel.org, netdev , Rob Herring To: Vladimir Oltean Return-path: Content-Disposition: inline In-Reply-To: Sender: linux-kernel-owner@vger.kernel.org List-Id: linux-spi.vger.kernel.org On Tue, Aug 27, 2019 at 09:16:39PM +0300, Vladimir Oltean wrote: > On Tue, 27 Aug 2019 at 21:13, Mark Brown wrote: > > > > On Tue, Aug 27, 2019 at 09:06:14PM +0300, Vladimir Oltean wrote: > > > On Tue, 27 Aug 2019 at 21:05, Mark Brown wrote: > > > > On Mon, Aug 26, 2019 at 04:10:51PM +0300, Vladimir Oltean wrote: > > > > > > > I noticed you skipped applying this patch, and I'm not sure that Shawn > > > > > will review it/take it. > > > > > Do you have a better suggestion how I can achieve putting the DSPI > > > > > driver in poll mode for this board? A Kconfig option maybe? > > > > > > DT changes go through the relevant platform trees, not the > > > > subsystem trees, so it's not something I'd expect to apply. > > > > > But at least is it something that you expect to see done through a > > > device tree change? > > > > Well, it's not ideal - if it performs better all the time the > > driver should probably just do it unconditionally. If there's > > some threashold where it tends to perform better then the driver > > should check for that but IIRC it sounds like the interrupt just > > isn't at all helpful here. > > I can't seem to find any situation where it performs worse. Hence my > question on whether it's a better idea to condition this behavior on a > Kconfig option rather than a DT blob which may or may not be in sync. DT is a description of hardware not condition for software behavior, where module parameter is usually used for. Shawn