On Wed 16 Jan 22:10 PST 2019, Balakrishna Godavarthi wrote:
> Hi Anderson,
>
> On 2019-01-17 10:10, Bjorn Andersson wrote:
[..]
> > +&qup_uart6_default {
> > + pinmux {
> > + pins = "gpio45", "gpio46", "gpio47", "gpio48";
> > + function = "qup6";
> > + };
> > +
> > + ctsrx {
> > + pins = "gpio45", "gpio48";
> > + drive-strength = <2>;
> > + bias-no-pull;
> > + };
> > +
> > + rts {
> > + pins = "gpio46";
> > + drive-strength = <2>;
> > + bias-pull-down;
> > + };
> > +
> > + tx {
> > + pins = "gpio47";
> > + drive-strength = <2>;
> > + bias-pull-up;
> > + };
> > +};
> > +
> > &qup_uart9_default {
> > pinconf-tx {
> > pins = "gpio4";
>
>
> [Bala]:
> GPIO 45 is CTS
> GPIO 46 is RTS
> GPIO 47 is Tx
> GPIO 48 is Rx.
>
> Tx & RTS are inputs to APPS processor, bias should be disable as the
> source i.e. BT chip will pull them up.
> CTS & RX are outputs from APPS processor, where as CTS is GPIO which
> need to toggled, so the default state should be pull down.
> RX is should be pulled up.
> when TX & RX are pulled high it indicates that the lines are ideal
> i.e. no data.
>
> Above is just my assumption, not sure whether they work on MTP.
>
I will update and verify.
Thanks,
Bjorn
