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Message-ID: <c7818782-ab41-b526-9e81-e769259baa52@redhat.com>
Date:   Tue, 1 Feb 2022 00:21:41 +0100
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Subject: Re: [PATCH 0/4] drm/tiny: Add driver for Solomon SSD1307 OLED
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To:     Simon Ser <contact@emersion.fr>
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>,
        Andy Shevchenko <andriy.shevchenko@linux.intel.com>,
        Lee Jones <lee.jones@linaro.org>
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From:   Javier Martinez Canillas <javierm@redhat.com>
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Hello Simon,

Thanks for your feedback.

On 1/31/22 21:39, Simon Ser wrote:
> On Monday, January 31st, 2022 at 21:36, Simon Ser <contact@emersion.fr> wrote:
> 
>> This driver only advertises XRGB8888 in ssd1307_formats. It would be nice to
>> expose R8 as well so that user-space can directly produce suitable buffers.
>> It would also be nice to have some kind of preferred format, so that user-space
>> knows R8 is preferred over XRGB8888.
> 
> Hm, since the format used by the hw is actually R1, adding that to drm_fourcc.h
> would be even better.
> 

Yes, agreed that would be nice. We discussed this already with Thomas and my
suggestion was to land the driver as is, advertising XRGB8888. Which is also
what the other driver using monochrome does (drivers/gpu/drm/tiny/repaper.c):

https://www.spinics.net/lists/dri-devel/msg331328.html

As a follow-up we can wire up al the needed bits to have a DRM/KMS driver that
could expose a R1 format.

> Let me know if you want me to type up any of the user-space bits.
> 

Thanks! I also could help to add the needed support in the user-space stack.

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