On Tue, Aug 27, 2019 at 12:00 AM Dmitry Torokhov <dmitry.torokhov@xxxxxxxxx> wrote: > > 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. Yeah this is something that has been discussed recently as Harish is suggesting to add an actual inverter to the device tree model. As the description of reality in the device tree is incomplete, these flags, which should nominally be consumer flags and indicate the behavior of the consumer, becomes a panacea for solving shortcomings in the device tree model. I am in favor of introducing explicit inverters in device tree, as it makes the descriptions more consistent: e.g. regulators are consumer oriented, they even model rails to make things very clear on where a voltage applies, whereas GPIO polarity is defined as "trial-and-error until whatever makes the system run" more or less. > 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. Sure, this is not the place for hashing out DT design issues, can you fix when applying or should I send a new version? Yours, Linus Walleij
