From mboxrd@z Thu Jan 1 00:00:00 1970 From: Grant Likely Subject: Re: [PATCH V2 2/2] spi/bcm63xx: work around inability to keep CS up Date: Tue, 05 Feb 2013 17:14:49 +0000 Message-ID: <20130205171449.8CD873E1499@localhost> References: <1359900913-4472-1-git-send-email-jogo@openwrt.org> <1359900913-4472-3-git-send-email-jogo@openwrt.org> <20130205143530.1F00D3E1265@localhost> <20130205160004.2817a8b08ba7bb8c2de9a382@openwrt.org> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Cc: spi-devel-general-5NWGOfrQmneRv+LV9MX5uipxlwaOVQ5f@public.gmane.org, Kevin Cernekee , Mark Brown , Florian Fainelli , Maxime Bizon To: Jonas Gorski Return-path: In-Reply-To: <20130205160004.2817a8b08ba7bb8c2de9a382-p3rKhJxN3npAfugRpC6u6w@public.gmane.org> List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: spi-devel-general-bounces-5NWGOfrQmneRv+LV9MX5uipxlwaOVQ5f@public.gmane.org List-Id: linux-spi.vger.kernel.org On Tue, 5 Feb 2013 16:00:04 +0100, Jonas Gorski wrote: > On Tue, 05 Feb 2013 14:35:30 +0000 > Grant Likely wrote: > > > On Sun, 3 Feb 2013 15:15:13 +0100, Jonas Gorski wrote: > > > This SPI controller does not support keeping CS asserted after sending > > > a transfer. > > > Since messages expected on this SPI controller are rather short, we can > > > work around it for normal use cases by sending all transfers at once in > > > a big full duplex stream. > > > > > > This means that we cannot change the speed between transfers if they > > > require CS to be kept asserted, but these would have been rejected > > > before anyway because of the inability of keeping CS asserted. > > > > > > Signed-off-by: Jonas Gorski > > > > Are you checking the state of transfer->cs_change when merging > > transfers? If cs_change is set, then the transfers cannot be merged. > > Yes, I do; I "flush" on each cs_change and after the last transfer: Okay, applied. Thanks. g. ------------------------------------------------------------------------------ Free Next-Gen Firewall Hardware Offer Buy your Sophos next-gen firewall before the end March 2013 and get the hardware for free! Learn more. http://p.sf.net/sfu/sophos-d2d-feb