From mboxrd@z Thu Jan 1 00:00:00 1970 From: Baruch Siach Subject: Re: [PATCH 1/6] spi-imx: add CSPI and eCSPI support for i.MX51 MCU Date: Thu, 2 Sep 2010 20:29:09 +0300 Message-ID: <20100902172908.GD2464@tarshish> References: <1283413924-14210-1-git-send-email-jason77.wang@gmail.com> <1283413924-14210-2-git-send-email-jason77.wang@gmail.com> <20100902145357.GL14214@pengutronix.de> <19583.48828.125104.712979@ipc1.ka-ro> Mime-Version: 1.0 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable Cc: Jason Wang , s.hauer@pengutronix.de, grant.likely@secretlab.ca, amit.kucheria@canonical.com, Uwe =?iso-8859-1?Q?Kleine-K=F6nig?= , spi-devel-general@lists.sourceforge.net, linux-arm-kernel@lists.infradead.org To: Lothar =?iso-8859-1?Q?Wa=DFmann?= Return-path: Content-Disposition: inline In-Reply-To: <19583.48828.125104.712979@ipc1.ka-ro> List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: linux-arm-kernel-bounces@lists.infradead.org Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=m.gmane.org@lists.infradead.org List-Id: linux-spi.vger.kernel.org Hi Lothar, On Thu, Sep 02, 2010 at 05:11:56PM +0200, Lothar Wa=DFmann wrote: > > > - if (cpu_is_mx25() || cpu_is_mx31() || cpu_is_mx35()) { > > > + /* i.MX51 has two eCSPI and one CSPI controllers, eCSPI controllers= are > > > + * not compatible with existing SPI controllers on other i.MX platf= orms, > > > + * while CSPI controller is 100% compatible with the one on the i.M= X35. > > > + * We set the platform device id to 2 for this CSPI at i.MX51 board= init > > > + * level to distinguish it from two eCSPI controllers. > > > + */ > > This comment is missing in Sascha's driver. I like it. > > BTW, I'd like to make use of platform ids in this driver. This would > > make this ugly "on imx51 id2 is a cspi" distinction unnecessary. > > = > > > + if (cpu_is_mx25() || cpu_is_mx31() || cpu_is_mx35() || > > > + (cpu_is_mx51() && (pdev->id =3D=3D 2))) { > I'd prefer a flag in the platform_data that tells the driver to act as > an eCSPI driver. This way the information about eCSPI or not would be > where it belongs (in the arch specific code). But this also increases the size of driver code, since the compiler can = resolve cpu_is_* at compile time, and drop the dead code. Maybe an is_ecspi = macro will make the above code clearer. baruch -- = ~. .~ Tk Open Systems =3D}------------------------------------------------ooO--U--Ooo------------= {=3D - baruch@tkos.co.il - tel: +972.2.679.5364, http://www.tkos.co.il -