On Mon, Aug 26, 2019 at 03:00:22PM -0700, Dmitry Torokhov wrote: > 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. Acked-by: Rob Herring <robh@xxxxxxxxxx>
