Re: [PATCH v5 2/3] tty: serial: qcom_geni_serial: Wakeup over UART RX

Stephen Boyd
2019-11-22T18:24:20Z

Quoting Akash Asthana (2019-11-21 22:46:32)
>
> On 11/16/2019 1:11 AM, Stephen Boyd wrote:
> > Quoting Akash Asthana (2019-11-15 02:00:44)
> >> On 11/14/2019 11:10 PM, Stephen Boyd wrote:
> >>> Quoting Akash Asthana (2019-11-13 02:48:56)
> >>>> Add system wakeup capability over UART RX line for wakeup capable UART.
> >>>> When system is suspended, RX line act as an interrupt to wakeup system
> >>>> for any communication requests from peer.
> >>> How does the RX line get remuxed as a GPIO interrupt here? Is that
> >>> through some pinctrl magic in DT or just via enabling/disabling the
> >>> interrupt?
> >> Yes, For wakeup capable UART node, we have registered UART RX line with
> >> TLMM interrupt controller in DT file . Example: if GPIO48 is UART RX line
> >>
> >> interrupts-extended =  <&intc GIC_SPI 607 IRQ_TYPE_LEVEL_HIGH>,  <&tlmm
> >> 48 IRQ_TYPE_EDGE_FALLING>;
> > Right. So is gpio48 muxed as 'uart' function forever and the interrupt
> > logic in tlmm is connected to that pad regardless of the function
> > selected? I thought that gpios through TLMM had to be muxed as function
> > 0, i.e. gpio function, so that interrupts worked. But maybe that's wrong
> > and it can work without that.
>
> Yes, gpio48 is muxed as "uart' function function forever. There is no
> need to mux gpio48 to
>
> gpio function, interrupts can work without that.
>

Ok thanks for confirming.