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Message-ID: <b8eb7111-43aa-cc8a-a1bc-f08e0f2987ed@redhat.com>
Date:   Wed, 26 Jan 2022 14:46:08 +0100
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Subject: Re: [PATCH v1 1/4] fbtft: Unorphan the driver
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To:     Andy Shevchenko <andriy.shevchenko@linux.intel.com>,
        Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc:     Andy Shevchenko <andy@kernel.org>, linux-fbdev@vger.kernel.org,
        Michael Hennerich <michael.hennerich@analog.com>,
        Helge Deller <deller@gmx.de>, linux-staging@lists.linux.dev,
        linux-kernel@vger.kernel.org, dri-devel@lists.freedesktop.org,
        Phillip Potter <phil@philpotter.co.uk>,
        Carlis <zhangxuezhi1@yulong.com>,
        Lee Jones <lee.jones@linaro.org>,
        Heiner Kallweit <hkallweit1@gmail.com>
References: <20220125202118.63362-1-andriy.shevchenko@linux.intel.com>
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 <YfFIpBb7lL4ukWjm@smile.fi.intel.com>
From:   Javier Martinez Canillas <javierm@redhat.com>
In-Reply-To: <YfFIpBb7lL4ukWjm@smile.fi.intel.com>
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On 1/26/22 14:12, Andy Shevchenko wrote:
> On Wed, Jan 26, 2022 at 12:26:36PM +0100, Greg Kroah-Hartman wrote:
>> On Wed, Jan 26, 2022 at 12:17:08PM +0100, Helge Deller wrote:
>>> On 1/26/22 11:31, Daniel Vetter wrote:
> 
> ...
> 
>>> You are describing a transitioning over to DRM - which is Ok.
>>> But on that way there is no need to ignore, deny or even kill usage scenarios
>>> which are different compared to your usage scenarios (e.g. embedded devices,
>>> old platforms, slow devices, slow busses, no 3D hardware features,
>>> low-color devices, ...).
>>
>> All of those should be handled by the drm layer, as Daniel keeps
>> pointing out.  If not, then the tinydrm layer needs to be enhanced to do
>> so.
>>
>> Anyone have a pointer to hardware I can buy that is one of these fbtft
>> drivers that I could do a port to drm to see just how much work is
>> really needed here?
> 
> I have bought myself (for other purposes, I mean not to convert the driver(s))
> SSD1306 based display (SPI), SSD1331 (SPI), HX88347d (parallel).
>

I've just bought a SSD1306 (I2C) based one and will attempt to write a DRM
driver using drivers/staging/fbtft/fb_ssd1306.c as a reference.

I didn't find one with a SPI interface but we can later add a transport for
that if I succeed.

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