From mboxrd@z Thu Jan 1 00:00:00 1970 From: Heiko Schocher Date: Wed, 18 Feb 2009 08:23:01 +0100 Subject: [U-Boot] [PATCH] 7/12 Multiadapter/multibus I2C, drivers part 4 In-Reply-To: References: <499548C2.7060305@denx.de> <49967FAC.6090905@denx.de> <4997CAAE.60401@denx.de> <20090216221606.344FD832E893@gemini.denx.de> Message-ID: <499BB755.3030003@denx.de> List-Id: MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: u-boot@lists.denx.de Hello ksi, ksi at koi8.net wrote: > On Mon, 16 Feb 2009, Wolfgang Denk wrote: > >> Dear ksi at koi8.net, >> >> In message you wrote: >>>> Yes, good point. But do we need more then one i2c adapter when running >>>> from flash? I see only one reason to use i2c when running from flash: >>>> accessing SPD EEprom ... and this "bus" could always be the first >>>> hw adapter. All other accesses to i2c should be moved to run when >>>> we are in ram. >>> You can have, e.g. TWO SPD EEPROMs on different busses. And please remember >>> that infamous "640K ought to be enough for anybody..." >> This is a very unlikely hypothetical case. Based on such assumptions >> you can design any arbitrary complexity in any code. >> >> For now, please lets assume that there is no such usage mode, and >> that we do not add complexity to support it. >> >> >>> I don't think there is a viable reason to object unless somebody came up >>> with something better. >> Well, complex code that is difficult to read and difficult to >> understand is a very viable reason to object, me thinks. > > The code is not all that complex. Most of the code is the same, there is > just a thin HAL over it. And it is _NOT_ for reading two SPDs on different > busses, it is for consistency and uniformity. Reading two SPDs is a free > bonus, there is no a single line of additional code for this. If the current pointer is writeable, this is also possible ... bye Heiko -- DENX Software Engineering GmbH, MD: Wolfgang Denk & Detlev Zundel HRB 165235 Munich, Office: Kirchenstr.5, D-82194 Groebenzell, Germany