On Tue Mar 10, 2026 at 7:02 PM CET, Conor Dooley wrote:
> On Fri, May 12, 2023 at 03:58:26PM +0200, Luca Weiss wrote:
>
>> +&qup_uart1_cts {
>> + /*
>> + * Configure a bias-bus-hold on CTS to lower power
>> + * usage when Bluetooth is turned off. Bus hold will
>> + * maintain a low power state regardless of whether
>> + * the Bluetooth module drives the pin in either
>> + * direction or leaves the pin fully unpowered.
>> + */
>> + bias-bus-hold;
>> +};
>> +
>> +&qup_uart1_rts {
>> + /* We'll drive RTS, so no pull */
>> + drive-strength = <2>;
>> + bias-disable;
>> +};
>> +
>> +&qup_uart1_rx {
>> + /*
>> + * Configure a pull-up on RX. This is needed to avoid
>> + * garbage data when the TX pin of the Bluetooth module is
>> + * in tri-state (module powered off or not driving the
>> + * signal yet).
>> + */
>> + bias-pull-up;
>> +};
>> +
>> +&qup_uart1_tx {
>> + /* We'll drive TX, so no pull */
>> + drive-strength = <2>;
>> + bias-disable;
>> +};
>
> I recently made some changes to pincfg-node.yaml to detect if there's
> conflicting properties used, and these got detected. Should these not
> do what has been done on the msm8998-xiaomi-sagit, and delete the
> inherited bias-foo from the dtsi?
> &blsp1_i2c5_sleep {
> /delete-property/ bias-pull-up;
> bias-disable;
> };
Yes, you're completely right.
In the final dtb qup-uart1-{cts,rts,rx,tx}-default-state contain two
bias-* properties, this must be wrong.
Thanks for pointing this out, I'll prepare a patch soon!
Regards
Luca
