Hi Dmitry, On Tue, 29 Jan 2013 17:16:29 -0800 Dmitry Torokhov <dmitry.torokhov@xxxxxxxxx> wrote: ... > On Tue, Jan 29, 2013 at 01:25:24PM +0100, Anatolij Gustschin wrote: > > On hardware with limited gpios one column select gpio can select > > two different rows when using some additional hardware logic: > > high value selects one row, low value selects another row. Add > > support for such matrix keyboards and document device tree > > bindings used to describe them. > > > > Since half of the columns is always not selected, interrupts won't be > > generated for press events on these columns. To generate interrupts > > for not selected columns we need to periodicaly switch to these columns > > in order to catch the potential press events. This is done by additional > > work function. > > So this effectively switches the driver from interrupt driven to polled > model, right? The device does not really need an interrupt anymore... Yes, partially. I do not need to scan the state of the rows right after column switching. The interrupts for press events will only be generated if a key in the affected row was actually pressed. So the device is still interrupt driven and the row state read-out happens in the work scheduled from the interrupt handler. Thanks, Anatolij -- To unsubscribe from this list: send the line "unsubscribe linux-input" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
