From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from moutng.kundenserver.de (moutng.kundenserver.de [212.227.126.186]) by ozlabs.org (Postfix) with ESMTP id 684CDDDE23 for ; Thu, 27 Sep 2007 19:21:43 +1000 (EST) From: Arnd Bergmann To: linuxppc-dev@ozlabs.org Subject: Re: [PATCH 5/7] Celleb: Supports VFD on Celleb 2 Date: Thu, 27 Sep 2007 11:07:33 +0200 References: <20070927.165631.-1300533671.kouish@swc.toshiba.co.jp> In-Reply-To: <20070927.165631.-1300533671.kouish@swc.toshiba.co.jp> MIME-Version: 1.0 Content-Type: text/plain; charset="iso-8859-1" Message-Id: <200709271107.33696.arnd@arndb.de> Cc: paulus@samba.org List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , On Thursday 27 September 2007, Ishizaki Kou wrote: > This is a patch to support VFD on Celleb 2. > VFD is a small LCD to show miscellaneous messages. > > Signed-off-by: Kou Ishizaki The implementation looks fine, but I'm not sure if /proc/ppc64/rtas is the right way to do it. The two problems I have with this are: * /proc files are generally not a good idea for new stuff. We carry around the existing /proc/ppc64/rtas files because we can't change the interface for existing stuff. My feeling is that your interface should better be implemented as a character device, or be integrating into some other existing message interface, if we can find one. * The firmware seems to implement the generic rtas interface for display-character and set-indicator, but your driver is celleb specific. I'd be feel more comfortable if we could come up with a driver that also works on other systems that implement the same rtas calls. Arnd <><