Re: [PATCH v6 3/6] drm: Add driver for Solomon SSD130x OLED displays

On 3/8/22 17:30, Geert Uytterhoeven wrote:

Hi Javier,

On Mon, Feb 14, 2022 at 2:37 PM Javier Martinez Canillas
[off-list ref] wrote:

quoted

This adds a DRM driver for SSD1305, SSD1306, SSD1307 and SSD1309 Solomon
OLED display controllers.

It's only the core part of the driver and a bus specific driver is needed
for each transport interface supported by the display controllers.

Signed-off-by: Javier Martinez Canillas <javierm@redhat.com>

Thanks for your patch, which is now commit a61732e808672cfa ("drm:
Add driver for Solomon SSD130x OLED displays") in drm/drm-next

Sorry for the delay, but finally I gave it a try on my Adafruit
FeatherWing 128x32 OLED.
Some of the weird issues (cursor disappears after printing some text,
more text also doesn't appear until I clear the display) are still there.

I see. Thought that I tested using it as a console and it did work
correctly for me. I'll do more tests again.

Unfortunately a regression was introduced since your v3: printed
text is mirrored upside-down. I.e. "E" is rendered correctly, but "L"
turns into "Γ" (Greek Gamma).
I suspect something went wrong with the display initialization
sequence.

Could you please try Chen-Yu's fix for the COM scan direction mask ?

https://lists.freedesktop.org/archives/dri-devel/2022-March/345915.html

I made a mistake when converting to use the GENMASK() and FIELD_PREP()
macros in v4 as suggested by Andy. The SSD130X_SET_COM_SCAN_DIR_MASK
wasn't correct which would explain the output to be vertically flipped.

-- 
Best regards,

Javier Martinez Canillas
Linux Engineering
Red Hat