Re: [PATCH 2/3] drm/tiny: ili9486: Do not assume 8-bit only SPI controllers

From: Carlo Caione
Date: Fri Nov 18 2022 - 14:04:19 EST


On 18/11/2022 16:44, Mark Brown wrote:

The problem arrives when your controller does support 16-bits, so your data is not swapped, but you still put the data on the bus with 8-bit transfers.

Why would you need to use 8 bit transfers if the controller supports
16 bits?

No idea why this driver is forcing 8-bit transfers when the controller
supports 16-bits (this is what this patch is fixing).

My theory is that this driver was written with the Raspberry Pi HATs in
mind and (AFAICT) the RPi has an 8-bit only SPI controller so the driver
author didn't bother with anything different.

--
Carlo Caione