From mboxrd@z Thu Jan 1 00:00:00 1970 From: Maxime Ripard Subject: Re: [PATCH 2/3] spidev: Add DT binding example. Date: Mon, 27 Apr 2015 12:05:37 +0200 Message-ID: <20150427100537.GQ5627@lukather> References: <20150426110144.GK22845@sirena.org.uk> <553CCABA.3090504@redhat.com> <12F80B18-7418-430E-94F7-5A20C133BA9A@martin.sperl.org> <20150426125113.GF5627@lukather> <20150426143359.GI5627@lukather> <553CF8F2.6070204@redhat.com> <20150426154728.GK5627@lukather> Reply-To: maxime.ripard-wi1+55ScJUtKEb57/3fJTNBPR1lH4CV8@public.gmane.org Mime-Version: 1.0 Content-Type: multipart/signed; micalg=pgp-sha1; protocol="application/pgp-signature"; boundary="ZqRzwd/9tauJXEMK" Cc: Hans de Goede , Martin Sperl , Mark Brown , linux-sunxi , Jonathan Corbet , linux-spi , linux-doc , Linux Kernel Mailing List To: Michal Suchanek Return-path: Content-Disposition: inline In-Reply-To: List-Post: , List-Help: , List-Archive: , List-Unsubscribe: , List-Id: linux-spi.vger.kernel.org --ZqRzwd/9tauJXEMK Content-Type: text/plain; charset=UTF-8 Content-Disposition: inline On Mon, Apr 27, 2015 at 08:51:12AM +0200, Michal Suchanek wrote: > On 26 April 2015 at 17:47, Maxime Ripard > wrote: > > On Sun, Apr 26, 2015 at 04:40:50PM +0200, Hans de Goede wrote: > >> Hi, > >> > >> I've a feeling everyone in this thread is ignoring the > >> raspberry pi use-case. Where the board is specifically > >> designed for educational purposes and used with lots of > >> peripherals which are usually programmed from userspace > >> using e.g. python bindings for i2c-dev or spidev, for > >> such a setup we really want spidev to be loaded on the > >> spibus by default and we really do not have a proper > >> compatible for a child device. > > > > I'm not sure we're ignoring it, it just is the exact same use case > > than the whole spidev use case: people want to write SPI userspace > > drivers, the rpi really is not special here, except maybe for its user > > space code base, but it really boils down to the same issue. > > > >> And no having to use per device devicetree overlays > >> for this is not the answer, this needs to be really > >> really easy. With pre device-tree kernels this just > >> works, we should be able to match that ease of use > >> with devicetree. > > > > We do agree on that. We repeatedly told that the DT was not a good > > solution, overlays or not, and this is exactly one of the reasons. > > > > Ok, so how about skipping the bindings altogether. > > Just instantiate a spidev for each SPI bus and each CS the SPI core > knows of once spidev is loaded. Which is exactly what my patch did but didn't seem like good enough for you at the time... Maxime -- Maxime Ripard, Free Electrons Embedded Linux, Kernel and Android engineering http://free-electrons.com --ZqRzwd/9tauJXEMK--