Re: [BISECTED] input: ads7846: touchscreen broken on Nokia 770

From: Aaro Koskinen
Date: Sat Mar 19 2022 - 11:13:54 EST


Hi,

On Sun, Feb 27, 2022 at 08:50:39PM +0200, Aaro Koskinen wrote:
> I noticed touchscreen does not work anymore on Nokia 770:
>
> [ 2.131011] ads7846 spi2.0: touchscreen, irq 175
> [ 2.200622] input: ADS7846 Touchscreen as /devices/platform/omap_uwire/spi_master/spi2/spi2.0/input/input0
>
> (then touching the screen:)
>
> [ 52.316894] ads7846 spi2.0: spi_sync --> -22
> [ 52.336944] ads7846 spi2.0: spi_sync --> -22
>
> bisected this to:
>
> commit 9c9509717b53e701469493a8d87ed42c7d782502
> Author: Oleksij Rempel <o.rempel@xxxxxxxxxxxxxx>
> Date: Wed Nov 11 16:39:05 2020 -0800
>
> Input: ads7846 - convert to full duplex
>
> It seems it's failing on SPI_CONTROLLER_HALF_DUPLEX check in
> __spi_validate(). The controller used on this board (spi-omap-uwire)
> sets that flag. How ads7846 is now supposed to work in that case after
> this conversion?

Any comments?

The touchscreen works after reverting the following patches:

6965eece2a89 ("Input: ads7846 - convert to one message")
9c9509717b53 ("Input: ads7846 - convert to full duplex")

A.