From mboxrd@z Thu Jan 1 00:00:00 1970 From: Marcel Ziswiler Subject: Re: [PATCH 2/3] arm: tegra: enable igb, stmpe, i2c chardev, spidev, lm95245, pwm leds Date: Tue, 10 Jun 2014 00:16:13 +0200 Message-ID: <5396322D.6030003@ziswiler.com> References: <39a8704a4c8170d6b0620a1e5e44042eae6d8810.1401665237.git.marcel@ziswiler.com> <538CA24B.1010602@wwwdotorg.org> <538CA635.4050502@ziswiler.com> <20140602221627.GP31751@sirena.org.uk> <538D64FD.2010909@ziswiler.com> <20140603094537.GQ31751@sirena.org.uk> <538EBACB.70100@ziswiler.com> <20140604111755.GG2520@sirena.org.uk> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <20140604111755.GG2520-GFdadSzt00ze9xe1eoZjHA@public.gmane.org> Sender: linux-tegra-owner-u79uwXL29TY76Z2rM5mHXA@public.gmane.org To: Mark Brown Cc: Stephen Warren , thierry.reding-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org, linux-lFZ/pmaqli7XmaaqVzeoHQ@public.gmane.org, devicetree-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, linux-arm-kernel-IAPFreCvJWM7uuMidbF8XUB+6BGkLq7r@public.gmane.org, linux-kernel-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, linux-tegra-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, stefan-XLVq0VzYD2Y@public.gmane.org List-Id: devicetree@vger.kernel.org On 06/04/2014 01:17 PM, Mark Brown wrote: > You're saying you're controlling it from userspace. This is a > particular detail of what you are doing in your system. You happen to > want to control the devices you are hanging off the system with > userspace drivers but that's just what you're doing right now. Sorry, I don't get it. Yes, spidev is to control stuff from user space just like i2c-dev however bad that might sound. > No, that's in the controller node - the chip selects are described > there. The child node references a chip select number that the master > has and describes what's connected to that chip select. Well, unfortunately SPI without any chip select is just plain simply useless. It won't work. > It's a perfectly fine way of controlling things from userspace if that's > a sensible way of controlling devices but that does not mean you should > describe it in the device tree in that fashion. Only that without describing such a chip select in the device tree spidev won't ever work. I don't see us reaching any consensus here therefore I retreat. I will re-submit the whole thing without spidev however sad having to see that useful feature being dropped.