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Date:   Sun, 27 Feb 2022 20:50:38 +0200
From:   Aaro Koskinen <aaro.koskinen@iki.fi>
To:     Dmitry Torokhov <dmitry.torokhov@gmail.com>,
        Oleksij Rempel <o.rempel@pengutronix.de>,
        linux-input@vger.kernel.org, linux-kernel@vger.kernel.org
Subject: [BISECTED] input: ads7846: touchscreen broken on Nokia 770
Message-ID: <20220227185038.GA3016@darkstar.musicnaut.iki.fi>
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Hi,

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@pengutronix.de>
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?

A.