Subject: Re: [PATCH 13/14] Blackfin SPI driver: Move cs_chg_udelay to
	cs_deactive to fix bug when some SPI LCD driver needs delay after
	cs_deactive
From: Bryan Wu <bryan.wu@analog.com>
Reply-To: bryan.wu@analog.com
To: David Brownell <david-b@pacbell.net>,
       Cameron Barfield <cbarfield@cyberdata.net>
Cc: Bryan Wu <bryan.wu@analog.com>, spi-devel-general@lists.sourceforge.net,
       linux-kernel@vger.kernel.org
In-Reply-To: <200710301319.00071.david-b@pacbell.net>
References: <1193735885-8202-1-git-send-email-bryan.wu@analog.com>
	 <1193735885-8202-14-git-send-email-bryan.wu@analog.com>
	 <200710301319.00071.david-b@pacbell.net>
Content-Type: text/plain
Content-Transfer-Encoding: 7bit
Organization: Analog Devices, Ltd.
Date: Wed, 31 Oct 2007 14:30:04 +0800
Message-Id: <1193812204.6971.14.camel@roc-laptop>
Mime-Version: 1.0
Sender: linux-kernel-owner@vger.kernel.org
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On Tue, 2007-10-30 at 13:18 -0700, David Brownell wrote:
> On Tuesday 30 October 2007, Bryan Wu wrote:
> > @@ -211,6 +211,10 @@ static void cs_deactive(struct driver_data *drv_data, struct chip_data *chip)
> >         flag |= (chip->flag << 8);
> >  
> >         write_FLAG(drv_data, flag);
> > +
> > +       /* Move delay here for consistency */
> > +       if (chip->cs_chg_udelay)
> > +               udelay(chip->cs_chg_udelay);
> >  }
> >  
> 
> By the way, if this is something needed very often, that mechanism
> should be moved into the SPI framework.  It wouldn't be polite if
> such LCD drivers could only work on Blackfin boards.  :)

I am not sure whether this LCD needs cs_chg_udelay on other boards.
It is found by Cameron Barfield. Maybe it is some timing requirement for
specific hardware.

-Bryan Wu
-
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