On Tue, Mar 26, 2019 at 12:31:46PM +0200, Tomi Valkeinen wrote: > Add DT properties needed for IRQ and HPD support. > > Signed-off-by: Tomi Valkeinen <tomi.valkeinen@xxxxxx> > Cc: devicetree@xxxxxxxxxxxxxxx > Cc: Rob Herring <robh@xxxxxxxxxx> > --- > > A quick summary of tc358767's HPD/GPIO support: > > tc358767 has two pins that can be used as GPIOs. Those can be used for > HPD by configuring the pin as input. tc358767 supports HW detection of a > "short" HPD pulse (programmable length) which can be used to detect > DisplayPort IRQ from the monitor. Afaik, this kind of short pulse > detection is not possible with common GPIOs found in SoCs. > > While I think the HPD support works ok, I'm unsure about the DT binding. > I first tried implementing the HPD as a gpiochip, but for interrupts I > then needed irqchip, and the amount of code started to increase a lot. > > I decided that gpiochip + irqchip just isn't worth the effort and > complexity here, as most likely the pins will ever be used for HPD. > > So, here I have a simple 'hpd-num' DT property to mark which (if any) of > the two GPIO pins is used for HPD. There's similar properties for other chips where some signal has a selectable pin assignment. > > Suggestions welcome. > > > .../devicetree/bindings/display/bridge/toshiba,tc358767.txt | 3 +++ > 1 file changed, 3 insertions(+) > > diff --git a/Documentation/devicetree/bindings/display/bridge/toshiba,tc358767.txt b/Documentation/devicetree/bindings/display/bridge/toshiba,tc358767.txt > index e3f6aa6a214d..79c71e7eb71f 100644 > --- a/Documentation/devicetree/bindings/display/bridge/toshiba,tc358767.txt > +++ b/Documentation/devicetree/bindings/display/bridge/toshiba,tc358767.txt > @@ -12,6 +12,9 @@ Optional properties: > (active high shutdown input) > - reset-gpios: OF device-tree gpio specification for RSTX pin > (active low system reset) > + - interrupt-parent: phandle of the parent interrupt controller Drop this, it is implied or in the parent. > + - interrupts: interrupt specifier for the bridge's interrupt > + - hpd-num: TC358767 GPIO pin number to which HPD is connected to (0 or 1) ti,hpd-pin > - ports: the ports node can contain video interface port nodes to connect > to a DPI/DSI source and to an eDP/DP sink according to [1][2]: > - port@0: DSI input port > -- > Texas Instruments Finland Oy, Porkkalankatu 22, 00180 Helsinki. > Y-tunnus/Business ID: 0615521-4. Kotipaikka/Domicile: Helsinki >
