Hi Linus, On Fri, Aug 23, 2019 at 09:10:21AM +0200, Linus Walleij wrote: > This switches the TSC2007 to use a GPIO descriptor to read > the pendown GPIO line. > > As this will make the gpiolib start to respect polarity > inversion flags on the GPIO lines, drop the inversion when > reading the line with gpio_get_value(), fix two offenders > in the i.MX device trees, and also emphasize the importance > of marking the polarity right in the device tree bindings. > > Cc: Denis Carikli <denis@xxxxxxxxxx> > Cc: Pengutronix Kernel Team <kernel@xxxxxxxxxxxxxx> > Cc: NXP Linux Team <linux-imx@xxxxxxx> > Cc: H. Nikolaus Schaller <hns@xxxxxxxxxxxxx> > Cc: devicetree@xxxxxxxxxxxxxxx > Signed-off-by: Linus Walleij <linus.walleij@xxxxxxxxxx> > --- > ChangeLog v1->v2: > - Drop inversion on the GPIO descriptor value, rely on the > gpiolib to handle polarity inversion. > - Comb through device trees, identify two offenders, fix > them as part of the patch for a clean cut. > - Also fix the device tree bindings. > --- > .../bindings/input/touchscreen/tsc2007.txt | 5 +++-- > arch/arm/boot/dts/imx35-eukrea-cpuimx35.dtsi | 3 ++- > arch/arm/boot/dts/imx51-eukrea-cpuimx51.dtsi | 3 ++- > drivers/input/touchscreen/tsc2007.h | 4 +++- > drivers/input/touchscreen/tsc2007_core.c | 14 +++++++------- > 5 files changed, 17 insertions(+), 12 deletions(-) > > diff --git a/Documentation/devicetree/bindings/input/touchscreen/tsc2007.txt b/Documentation/devicetree/bindings/input/touchscreen/tsc2007.txt > index ed00f61b8c08..b08b54d49699 100644 > --- a/Documentation/devicetree/bindings/input/touchscreen/tsc2007.txt > +++ b/Documentation/devicetree/bindings/input/touchscreen/tsc2007.txt > @@ -7,7 +7,8 @@ Required properties: > > Optional properties: > - gpios: the interrupt gpio the chip is connected to (trough the penirq pin). > - The penirq pin goes to low when the panel is touched. > + The penirq pin goes to low when the panel is touched, so make sure to tag > + the GPIO line with GPIO_ACTIVE_LOW. I think this is too strong. I am sure that one can come up with a way to connect the attention signal though polarity inverter and then one would have to specify GPIO_ACTIVE_HIGH in the DT. Can we say: The penirq pin goes to low when the panel is touched, so GPIO line should normally be tagged with GPIO_ACTIVE_LOW. Thanks. -- Dmitry
