Interfacing (DSI, CSI, I2C, etc.) • Re: SPI display for RPI5 with dtoverlay?

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I would be willing to fund it though, if anyone would care to take it on? I know 6by9 doesn't - so not asking but if either of you know someone who might be interested I 'd appreciate a contact by PM.
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there is no PM feature on this forum!

'Willing to fund'? Sorry, but do you think other peoples time is priceless?
If you want that you will have to do it yourself or pay someone to do it for you - will be more than 16bucks for sure!
If you need advice which LCD manufacturer to use you may be in need of some consultant as well.

@Bugsworstnightmare - I am more than happy to pay someone to do this - that is exactly what I meant by "willing to fund". Sorry I wasn't a little clearer in articulating that and caused you to misunderstand. I very much do value the skill and expertise engineers like yourself have. It takes many years to acquire those levels and I very much do appreciate the generosity you show by sharing your know how and experience on these forums with folk like myself, who must sometimes appear to be as thick as a brick or lazy or just naive. I wasn't aware there is no PM feature so thank you for pointing that out. Not sure what is the best way to put my hand up to ask if someone with the right skill set would be interested in tackling this as a paid work item. Suggestions welcome.

@6by9 Thank you for your encouragement and the how to! However I know my limitations and as an old dog (76 last week), new tricks are becoming increasingly hard to learn and retain. I do enjoy trying though! Re-reading the Viewtopics on SPI LCD overlays that you and Bugsworstnightmare have contributed a considerable amount of time and effort to has helped me get something working at last and with a bit of trial and error I now have one of the target SPI LCDs (Waveshare SKU18366) fired up and displaying the command line. That's the good news - and it confirms my wiring is OK. The bad news is I can only get this to work on Pi4 by using the fbtft driver, I haven't been able to get anything working on the same DUT using the mipi-dbi-spi driver. My OP stated the objective was to be able to connect these two LCDs to a Pi4 or Pi5 and get them running on the current mainstream Raspberry Pi OSs with nothing more than an appropriately written config.txt and cmdline.tx. No recompiling kernels or other black magic. This of course requires there to be a kernel driver and the right overlay/s in the current OS for these two Waveshare LCDs SKU18366 (ili9341) and SKU27479 (st7789v). That would appear to be the case for fbtft and I am hoping it is also true for mipi-dbi-spi and that the problem I have is is related to overlays and params.
I know there has been and maybe there still is an ongoing effort to migrate fbtft drivers across to mipi-dbi-spi. Am I wrong in thinking that is NOT yet the case for these two LCDs? Or should they work with mipi-dbi-spi if the overlays and params are correclty expressed in config.txt?

Here is what I have tried so far...

DUT

Raspberry Pi 4 running 64 bit Bookworm Desktop from SD Card, booting to command line.
SPI LCD SKU18366 Waveshare connected to GPIO and HDMI monitor on HDM! 0

fbtft driver boots to SPI LCD display but mipi-dbi-spi boots to HDMI monitor with no output on LCD.
startx launches Desktop as expected.

Fresh clean installation on 32GB SD Card Aug 1 2024
Only changes made are to config.txt and cmdline.txt

viota@raspberrypi:~ $ uname -a
Linux raspberrypi 6.6.31+rpt-rpi-v8 #1 SMP PREEMPT Debian 1:6.6.31-1+rpt1 (2024-05-29) aarch64 GNU/Linux

Latest eeprom firmware
viota@raspberrypi:~ $ sudo rpi-eeprom-update
BOOTLOADER: up to date
CURRENT: Mon Apr 15 01:12:14 PM UTC 2024 (1713186734)
LATEST: Mon Apr 15 01:12:14 PM UTC 2024 (1713186734)
RELEASE: default (/lib/firmware/raspberrypi/bootloader-2711/default)
Use raspi-config to change the release.

VL805_FW: Using bootloader EEPROM
VL805: up to date
CURRENT: 000138c0
LATEST: 000138c0


Extract from config.txt
#Waveshare 2.4inch SPI LCD SKU18366 - the fbtft overlay works and boots to LCD cli screen

dtoverlay=fbtft,spi0-0,ili9341
dtparam=width=240,height=320
dtparam=reset_pin=27,dc_pin=25,led_pin=18
dtparam=rotate=270
#NB width and height transposed to get LCD screen format correct.
--------------------------------------

#Waveshare 2.4 inch SPI LCD SKU18366 - the mipi-dbi-spi overlay does not show anything on LCD although it has reset and is no backlight. #DUT boots to HDMI cli.

dtparam=spi=on
dtoverlay=spi0-2cs
dtoverlay=mipi-dbi-spi,spi0-0,speed=32000000
dtparam=compatible=ili9341\0panel-mipi-dbi-spi
dtparam=width=240,height=320
dtparam=reset-gpio=27,dc-gpio=25,backlight-gpio=18
dtparam=rotate=270
------------------------------------

#Same LCD with mipi-dbi-spi overlay variation, does not show anything on LCD although it has reset and is no backlight. Boots to HDMI cli.
#Waveshare 2.4inch SPI LCD SKU18366

dtoverlay=fbtft,spi0-0,ili9341
dtparam=width=240,height=320
dtparam=reset_pin=27,dc_pin=25,led_pin=18lsmod
dtparam=rotate=270
-----------------------------------

#Same LCD with mipi-dbi-spi driver variation, does not show anything on LCD although it has reset and is no backlight. Boots to HDMI cli
dtparam=spi=on
dtoverlay=spi0-2cs
dtoverlay=mipi-dbi-spi,spi0-0,speed=32000000,ili9341
#dtparam=compatible=ili9341\0panel-mipi-dbi-spi
dtparam=width=240,height=320
dtparam=reset-gpio=27,dc-gpio=25,backlight-gpio=18
dtparam=rotation=270
#trying rotation as rotate is ignored

Statistics: Posted by peter.arq — Fri Aug 09, 2024 5:57 pm

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