From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.1 (2015-04-28) on archive.lwn.net X-Spam-Level: X-Spam-Status: No, score=-5.8 required=5.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,RCVD_IN_DNSWL_HI autolearn=unavailable autolearn_force=no version=3.4.1 Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by archive.lwn.net (Postfix) with ESMTP id EA0E27D062 for ; Wed, 27 Jun 2018 07:20:52 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752680AbeF0HUw convert rfc822-to-8bit (ORCPT ); Wed, 27 Jun 2018 03:20:52 -0400 Received: from mail.bootlin.com ([62.4.15.54]:58542 "EHLO mail.bootlin.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752741AbeF0HUu (ORCPT ); Wed, 27 Jun 2018 03:20:50 -0400 Received: by mail.bootlin.com (Postfix, from userid 110) id A8BA12079C; Wed, 27 Jun 2018 09:20:47 +0200 (CEST) Received: from bbrezillon (AAubervilliers-681-1-87-188.w90-88.abo.wanadoo.fr [90.88.29.188]) by mail.bootlin.com (Postfix) with ESMTPSA id E60E8206D8; Wed, 27 Jun 2018 09:20:36 +0200 (CEST) Date: Wed, 27 Jun 2018 09:20:36 +0200 From: Boris Brezillon To: Randy Dunlap Cc: Wolfram Sang , linux-i2c@vger.kernel.org, Jonathan Corbet , linux-doc@vger.kernel.org, Greg Kroah-Hartman , Arnd Bergmann , Przemyslaw Sroka , Arkadiusz Golec , Alan Douglas , Bartosz Folta , Damian Kos , Alicja Jurasik-Urbaniak , Cyprian Wronka , Suresh Punnoose , Rafal Ciepiela , Thomas Petazzoni , Nishanth Menon , Rob Herring , Pawel Moll , Mark Rutland , Ian Campbell , Kumar Gala , devicetree@vger.kernel.org, linux-kernel@vger.kernel.org, Vitor Soares , Geert Uytterhoeven , Linus Walleij , Xiang Lin , linux-gpio@vger.kernel.org, Sekhar Nori , Przemyslaw Gaj Subject: Re: [PATCH v5 02/10] docs: driver-api: Add I3C documentation Message-ID: <20180627092036.605dbf12@bbrezillon> In-Reply-To: <4898e391-f954-a399-0bca-7588942280b9@infradead.org> References: <20180622104930.32050-1-boris.brezillon@bootlin.com> <20180622104930.32050-3-boris.brezillon@bootlin.com> <4898e391-f954-a399-0bca-7588942280b9@infradead.org> X-Mailer: Claws Mail 3.15.0-dirty (GTK+ 2.24.31; x86_64-pc-linux-gnu) MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8BIT Sender: linux-doc-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-doc@vger.kernel.org Hi Randy, On Tue, 26 Jun 2018 14:07:49 -0700 Randy Dunlap wrote: > > + > > +I3C Private SDR transfers > > +------------------------- > > + > > +Private SDR (Single Data Rate) transfers should be used for anything that is > > +device specific and does not require high transfer speed. > > + > > +It is the equivalent of I2C transfers but in the I3C world. Each transfer is > > +passed the device address (dynamic address assigned during DAA), a payload > > +and a direction. > > + > > +The only difference with I2C is that the transfer is much faster (typical SCL > > what is SCL? It's not used anywhere else in this doc. It's an acronym used by I²C, it means Serial Clock Line. I'll just replace that by "typical clock frequency is 12.5MHz". > > > +frequency is 12.5MHz). > > + > > +I3C HDR commands > > +---------------- > > + > > +HDR commands should be used for anything that is device specific and requires > > +high transfer speed. > > + > > +The first thing attached to an HDR command is the HDR mode. There are currently > > +3 different modes defined by the I3C specification (refer to the specification > > +for more details): > > + > > +* HDR-DDR: Double Data Rate mode > > +* HDR-TSP: Ternary Symbol Pure. Only usable on busses with no I2C devices > > +* HDR-TSL: Ternary Symbol Legacy. Usable on busses with I2C devices > > + > > +When sending an HDR command, the whole bus has to enter HDR mode, which is done > > +using a broadcast CCC command. > > +Once the bus has entered a specific HDR mode, the master sends the HDR command. > > +An HDR command is made of: > > + > > +* one 16-bits command word > > +* N 16-bits data words > > I supposed the I3C spec will tell me the byte order of these words on the bus? > or this doc could tell us here. It's big endian. I'll make it clear in this doc. I'll also fix all the other mistakes you pointed out. > > and you can add (if you want to): > Reviewed-by: Randy Dunlap I'll definitely add your R-b. Thanks for the review. Boris -- To unsubscribe from this list: send the line "unsubscribe linux-doc" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html