Re: [PATCH v1 3/4] serial: qcom-geni: Enable PM runtime for serial driver

[Dmitry Baryshkov]

On 31/12/2025 07:49, Praveen Talari wrote:
> Hi Dmitry,
>
> On 12/31/2025 8:30 AM, Dmitry Baryshkov wrote:
> > On 31/12/2025 05:00, Praveen Talari wrote:
> > > Hi Dmitry,
> > >
> > > On 12/30/2025 11:53 PM, Dmitry Baryshkov wrote:
> > > > On Mon, Nov 10, 2025 at 03:40:42PM +0530, Praveen Talari wrote:
> > > > > The GENI serial driver currently handles power resource management
> > > > > through calls to the statically defined geni_serial_resources_on() and
> > > > > geni_serial_resources_off() functions. This approach reduces 
> > > > > modularity
> > > > > and limits support for platforms with diverse power management
> > > > > mechanisms, including resource managed by firmware.
> > > > >
> > > > > Improve modularity and enable better integration with platform- 
> > > > > specific
> > > > > power management, introduce support for runtime PM. Use
> > > > > pm_runtime_resume_and_get() and pm_runtime_put_sync() within the
> > > > > qcom_geni_serial_pm() callback to control resource power state
> > > > > transitions based on UART power state changes.
> > > > >
> > > > > Signed-off-by: Praveen Talari <praveen.talari@xxxxxxxxxxxxxxxx>
> > > > > ---
> > > > >   drivers/tty/serial/qcom_geni_serial.c | 24 ++++++++++++++++++++++--
> > > > >   1 file changed, 22 insertions(+), 2 deletions(-)
> > > >
> > > > This breaks BT support on the Qualcomm RB2 platform. With this patch
> > > > applied, I'm getting the following:
> > > >
> > > > root@qcom-armv8a:~# dmesg | grep tty\\\|hci0
> > > > [    0.000000] Kernel command line:  ignore_loglevel 
> > > > console=ttyMSM0,115200n8 earlycon root=PARTLABEL=rootfs rootwait 
> > > > systemd.mask=pd-mapper.service -- 
> > > > androidboot.bootdevice=4744000.sdhci androidboot.serialno=2b89b520 
> > > > androidboot.baseband=apq 
> > > > msm_drm.dsi_display0=qcom,mdss_dsi_ext_bridge_1080p:
> > > > [    4.074354] 4a8c000.serial: ttyHS1 at MMIO 0x4a8c000 (irq = 140, 
> > > > base_baud = 0) is a MSM
> > > > [    4.099410] serial serial0: tty port ttyHS1 registered
> > > > [    4.131200] Bluetooth: hci0: setting up wcn399x
> > > > [    4.149847] 4a90000.serial: ttyMSM0 at MMIO 0x4a90000 (irq = 142, 
> > > > base_baud = 0) is a MSM
> > > > [    4.229099] printk: legacy console [ttyMSM0] enabled
> > > > [    6.499519] Bluetooth: hci0: command 0xfc00 tx timeout
> > > > [    6.514347] Bluetooth: hci0: Reading QCA version information 
> > > > failed (-110)
> > > > [    6.559933] Bluetooth: hci0: Retry BT power ON:0
> > > > [    8.016330] systemd[1]: Created slice Slice /system/getty.
> > > > [    8.066194] systemd[1]: Created slice Slice /system/serial-getty.
> > > > [    8.148389] systemd[1]: Expecting device /dev/ttyMSM0...
> > > > [    8.956804] Bluetooth: hci0: command 0xfc00 tx timeout
> > > > [    8.962447] Bluetooth: hci0: Reading QCA version information 
> > > > failed (-110)
> > > > [    8.976917] Bluetooth: hci0: Retry BT power ON:1
> > > > [   11.296715] Bluetooth: hci0: command 0xfc00 tx timeout
> > > > [   11.302340] Bluetooth: hci0: Reading QCA version information 
> > > > failed (-110)
> > > > [   11.309534] Bluetooth: hci0: Retry BT power ON:2
> > > > [   13.660078] Bluetooth: hci0: command 0xfc00 tx timeout
> > > > [   13.665814] Bluetooth: hci0: Reading QCA version information 
> > > > failed (-110)
> > >
> > > Sure, will check and update.
> > >
> > > If possible, can you share what is DT filename for RB2.
> >
> > qrb4210-rb2.dts
>
> Can you please try below change on target since i didn't get target yet?

Yes, I have this patch too. It didn't help.

> diff --git a/arch/arm64/boot/dts/qcom/qrb4210-rb2.dts b/arch/arm64/boot/ 
> dts/qcom/qrb4210-rb2.dts
> index 0cd36c54632f..5f8613150bdd 100644
> --- a/arch/arm64/boot/dts/qcom/qrb4210-rb2.dts
> +++ b/arch/arm64/boot/dts/qcom/qrb4210-rb2.dts
> @@ -694,7 +694,7 @@ sdc2_card_det_n: sd-card-det-n-state {
>
>   &uart3 {
>          interrupts-extended = <&intc GIC_SPI 330 IRQ_TYPE_LEVEL_HIGH>,
> -                             <&tlmm 11 IRQ_TYPE_LEVEL_HIGH>;
> +                             <&tlmm 11 IRQ_TYPE_EDGE_FALLING>;
>          pinctrl-0 = <&uart3_default>;
>          pinctrl-1 = <&uart3_sleep>;
>          pinctrl-names = "default", "sleep";
>
> Thanks,
> Praveen Talari
>
> > > Earlier I had validated on RB1 and Kodiak.
> > >
> > > Thanks,
> > > Praveen
> > >
> > > > After reverting the next and this patches, BT is back to normal:
> > > >
> > > > [    4.067201] 4a8c000.serial: ttyHS1 at MMIO 0x4a8c000 (irq = 140, 
> > > > base_baud = 0) is a MSM
> > > > [    4.082426] serial serial0: tty port ttyHS1 registered
> > > > [    4.106122] 4a90000.serial: ttyMSM0 at MMIO 0x4a90000 (irq = 142, 
> > > > base_baud = 0) is a MSM
> > > > [    4.108647] Bluetooth: hci0: setting up wcn399x
> > > > [    4.125371] printk: legacy console [ttyMSM0] enabled
> > > > [    4.445205] Bluetooth: hci0: QCA Product ID   :0x0000000a
> > > > [    4.450927] Bluetooth: hci0: QCA SOC Version  :0x40020150
> > > > [    4.456470] Bluetooth: hci0: QCA ROM Version  :0x00000201
> > > > [    4.462006] Bluetooth: hci0: QCA Patch Version:0x00000001
> > > > [    4.509408] Bluetooth: hci0: QCA controller version 0x01500201
> > > > [    4.515656] Bluetooth: hci0: QCA Downloading qca/apbtfw11.tlv
> > > > [    5.488739] Bluetooth: hci0: QCA Downloading qca/apnv11.bin
> > > > [    5.671740] Bluetooth: hci0: QCA setup on UART is completed
> > > > [    7.993368] systemd[1]: Created slice Slice /system/getty.
> > > > [    8.045612] systemd[1]: Created slice Slice /system/serial-getty.
> > > > [    8.125418] systemd[1]: Expecting device /dev/ttyMSM0...


--
With best wishes
Dmitry