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Message-ID: <f8d71acb-5c8b-ac4e-0c32-38eb66af04c3@redhat.com>
Date:   Tue, 1 Feb 2022 12:31:44 +0100
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Subject: Re: [PATCH 0/4] drm/tiny: Add driver for Solomon SSD1307 OLED
 displays
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To:     Andy Shevchenko <andriy.shevchenko@linux.intel.com>,
        Sam Ravnborg <sam@ravnborg.org>
Cc:     linux-kernel@vger.kernel.org, linux-pwm@vger.kernel.org,
        linux-fbdev@vger.kernel.org,
        Thomas Zimmermann <tzimmermann@suse.de>,
        David Airlie <airlied@linux.ie>,
        Daniel Vetter <daniel.vetter@ffwll.ch>,
        Mark Brown <broonie@kernel.org>,
        dri-devel@lists.freedesktop.org,
        Liam Girdwood <lgirdwood@gmail.com>,
        =?UTF-8?Q?Noralf_Tr=c3=b8nnes?= <noralf@tronnes.org>,
        Geert Uytterhoeven <geert@linux-m68k.org>,
        Maxime Ripard <maxime@cerno.tech>,
        =?UTF-8?Q?Uwe_Kleine-K=c3=b6nig?= <u.kleine-koenig@pengutronix.de>,
        Thierry Reding <thierry.reding@gmail.com>,
        Lee Jones <lee.jones@linaro.org>
References: <20220131201225.2324984-1-javierm@redhat.com>
 <YfhM97cVH3+lJKg0@ravnborg.org> <Yfj/XGRRDNABsLPm@smile.fi.intel.com>
From:   Javier Martinez Canillas <javierm@redhat.com>
In-Reply-To: <Yfj/XGRRDNABsLPm@smile.fi.intel.com>
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On 2/1/22 10:37, Andy Shevchenko wrote:
> On Mon, Jan 31, 2022 at 09:56:23PM +0100, Sam Ravnborg wrote:
>> On Mon, Jan 31, 2022 at 09:12:20PM +0100, Javier Martinez Canillas wrote:
> 
> ...
> 
>>> Patch #3 adds the driver. The name ssd1307 was used instead of ssd130x
>>> (which would be more accurate) to avoid confusion for users who want to
>>> migrate from the existing ssd1307fb fbdev driver.
>> Looking forward the name ssd130x would make more sense. There is only so
>> many existing users and a potential of much more new users.
>> So in my color of the world the naming that benefits the most users
>> wins.
> 
> It depends if the binding is going to be preserved. Also this series doesn't
> answer to the question what to do with the old driver.
>

I don't plan to remove the old driver (yet). My goal here is to have an answer
for Fedora users that might complain that we disabled all the fbdev drivers.

So I wanted to understand the effort involved in porting a fbdev driver to DRM.

> If you leave it, I would expect the backward compatibility, otherwise the
> series misses removal of the old driver.
> 

I don't see how those two are correlated. You just need different compatible
strings to match the new and old drivers. That what was usually done for DRM
drivers that were ported. To give an example, the "omapfb" vs "omapdrm".

Since the current binding has a compatible "ssd1305fb-i2c", we could make the
new one "ssd1305drm-i2c" or better, just "ssd1305-i2c".

Best regards,
-- 
Javier Martinez Canillas
Linux Engineering
Red Hat