Re: [PATCH 00/23] Nokia N950 display support
From: Tomi Valkeinen
Date: Wed Mar 09 2016 - 02:11:03 EST
On 08/03/16 22:45, Sebastian Reichel wrote:
> On Tue, Mar 08, 2016 at 08:39:08PM +0200, Aaro Koskinen wrote:
>> On Tue, Mar 08, 2016 at 05:39:32PM +0100, Sebastian Reichel wrote:
>>> This series adds support for the Nokia N950 display.
>>> Since the panel is using DSI command mode, it involves
>>> adding support for manually updated displays to
>> Works OK, but the picture seems to be upside down?
> vertical, upside down is the native panel orientation.
>> Also shouldn't the default orientation be landscape?
> The N950 vendor kernel contains some code adding DSI
> rotation support with half-frame update mechnism to
> avoid tearing. It's quite complex and as far as I
> understand it also error-prone. Tomi knows more about
It needs support in both the panel driver and the dispc driver, and is
quite intrusive. Or, at least it was with omapfb, I can't say if it
could somehow be implemented more cleanly with omapdrm. It's definitely
not something I will be working on.
> I have a simpler patch without the half-frame update
> stuff, which works fine for me. I didn't notice any
> tearing, but I haven't done any really fast image
You will see diagonal tearing with that rotation. But maybe that's not
an issue. I think it's the best option available if landscape mode is
> updating. Also omapdrm has rotation support using
> the DSS hardware, which also seems to work ok. I'm
> still checking out what method is most suitable for
Hmm there's only so called DMA rotation, which shouldn't work. It's only
meant for really small displays, when the framebuffer is in SRAM. So I'm
a bit baffled as to what rotation you are using and why is it working =).
There is also VRFB rotation on omap3, but that's not supported by omapdrm.
> But yeah, we probably want to change the default
> rotation. Especially since touchscreen should have
> the same default rotation as the screen. (TS is
> horizontal, correct orientation for keyboard usage)
I don't know much about touchscreens, but I'm guessing that it's easier
to rotate the coordinates from touch than achieve good panel rotation on
Description: OpenPGP digital signature