From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([208.118.235.92]:35357) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1SFBAl-0005c5-Gb for qemu-devel@nongnu.org; Tue, 03 Apr 2012 17:21:53 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1SFBAj-0005h1-A3 for qemu-devel@nongnu.org; Tue, 03 Apr 2012 17:21:51 -0400 Received: from relay1.mentorg.com ([192.94.38.131]:34155) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1SFBAj-0005gb-41 for qemu-devel@nongnu.org; Tue, 03 Apr 2012 17:21:49 -0400 From: Paul Brook Date: Tue, 3 Apr 2012 22:22:21 +0100 References: <201204031845.09827.paul@codesourcery.com> In-Reply-To: MIME-Version: 1.0 Content-Type: Text/Plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Message-Id: <201204032222.21836.paul@codesourcery.com> Subject: Re: [Qemu-devel] [RFC PATCH v1 1/4] SPI: initial support List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: Peter Maydell Cc: Peter Crosthwaite , edgar.iglesias@gmail.com, qemu-devel@nongnu.org, john.williams@petalogix.com > 2012/4/3 Paul Brook : > >> > I'm no SPI expert, but a bit of googling suggests that it's > >> > a synchronous duplex bus, so you always send a byte of data > >> > to the slave and get one back in return (even if for some slaves > >> > it might be random garbage). > > > > Waitaminute. So this is just basic synchronous serial? > > > > We already have an API for this. hw/spi.c. > > Er, no we don't, not in upstream QEMU. You'll notice that > the patch we're discussing creates hw/spi.c as a new file... Sorry, I mean hw/ssi.c Synchronous serial is something that pretty much every vendor has their own name for, but in practice they're actually all the same. Paul