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Message-ID: <049fae0ebe5521d4bb92d7d0f66cd2a54a1a2d22.camel@linux.intel.com>
Subject: Re: [PATCH v3 1/2] dt-bindings: at24: Add address-width property
From:   Andy Shevchenko <andriy.shevchenko@linux.intel.com>
To:     Sakari Ailus <sakari.ailus@linux.intel.com>,
        Bartosz Golaszewski <brgl@bgdev.pl>
Cc:     alanx.chiang@intel.com, linux-i2c <linux-i2c@vger.kernel.org>,
        andy.yeh@intel.com, Rajmohan Mani <rajmohan.mani@intel.com>,
        Andy Shevchenko <andy.shevchenko@gmail.com>,
        tfiga@chromium.org, jcliang@chromium.org,
        Rob Herring <robh+dt@kernel.org>,
        Mark Rutland <mark.rutland@arm.com>,
        Arnd Bergmann <arnd@arndb.de>,
        Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
        Linux Kernel Mailing List <linux-kernel@vger.kernel.org>,
        devicetree <devicetree@vger.kernel.org>
Date:   Wed, 27 Jun 2018 14:41:35 +0300
In-Reply-To: <20180627094013.e42crqqufo2jqra6@paasikivi.fi.intel.com>
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         <20180627094013.e42crqqufo2jqra6@paasikivi.fi.intel.com>
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On Wed, 2018-06-27 at 12:40 +0300, Sakari Ailus wrote:
> On Wed, Jun 27, 2018 at 10:19:38AM +0200, Bartosz Golaszewski wrote:
> > 2018-06-27 7:46 GMT+02:00  <alanx.chiang@intel.com>:
> > > From: Alan Chiang <alanx.chiang@intel.com>
> > > 
> > > The AT24 series chips use 8-bit address by default. If some
> > > chips would like to support more than 8 bits, the at24 driver
> > > should be added the compatible field for specfic chips.
> > > 
> > > Provide a flexible way to determine the addressing bits through
> > > address-width in this patch.
> > > 
> > > Signed-off-by: Alan Chiang <alanx.chiang@intel.com>
> > > Signed-off-by: Andy Yeh <andy.yeh@intel.com>
> > > 
> > > ---
> > > since v1:
> > > -- Remove the address-width field in the example.
> > > since v2:
> > > -- Remove redundant space.
> > > 
> > > ---
> > >  Documentation/devicetree/bindings/eeprom/at24.txt | 2 ++
> > >  1 file changed, 2 insertions(+)
> > > 
> > > diff --git a/Documentation/devicetree/bindings/eeprom/at24.txt
> > > b/Documentation/devicetree/bindings/eeprom/at24.txt
> > > index 61d833a..aededdb 100644
> > > --- a/Documentation/devicetree/bindings/eeprom/at24.txt
> > > +++ b/Documentation/devicetree/bindings/eeprom/at24.txt
> > > @@ -72,6 +72,8 @@ Optional properties:
> > > 
> > >    - wp-gpios: GPIO to which the write-protect pin of the chip is
> > > connected.
> > > 
> > > +  - address-width: number of address bits (one of 8, 16).
> > > +
> > >  Example:
> > > 
> > >  eeprom@52 {
> > > --
> > > 2.7.4
> > > 
> > 
> > Rob,
> > 
> > we only have two possibilities here and the default is 8 bits.
> > 
> > What do you think about introducing a boolean property here called:
> > 'address-width-16' instead of an integer?
> 
> I'd have thought the same, but it turns out address-width is already
> being
> used by the at25 bindings:
> 
> Documentation/devicetree/bindings/eeprom/at25.txt
> 

Agree with Sakari, there is no need to evolve a chaos in DT bindings. We
have too many semi-hemi-duplications in bindings. Especially in this
case we have already established property by a similar driver.

-- 
Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Intel Finland Oy