On Mon, Nov 20, 2023 at 11:05:04PM +0100, Paul Menzel wrote:
> [Cc: +Rocky Liao as Qualcomm developer]
> Am 20.11.23 um 19:10 schrieb Alan Stern:
> > Again, nothing out of the ordinary. Maybe dynamic debugging will give
> > us a clue. Try doing this:
> >
> > Unload the btusb module.
> >
> > echo module usbcore +p >/sys/kernel/debug/dynamic_debug/control
> >
> > Load the btusb module
> >
> > Make sure that Bluetooth is turned off in Gnome
> >
> > Wait a few seconds
> >
> > echo module usbcore -p >/sys/kernel/debug/dynamic_debug/control
> >
> > Then let's see what the dmesg log contains for that time period.
>
>
> ```
> $ sudo modprobe -r btusb
> $ sudo dmesg | tail -1
> [340309.272439] usbcore: deregistering interface driver btusb
> $ echo module usbcore +p | sudo tee /sys/kernel/debug/dynamic_debug/control
> module usbcore +p
> $ sudo modprobe btusb
> $ /sbin/rfkill
> ID TYPE DEVICE SOFT HARD
> 1 wlan phy0 unblocked unblocked
> 36 bluetooth hci0 blocked unblocked
> $ echo module usbcore -p | sudo tee /sys/kernel/debug/dynamic_debug/control
> module usbcore -p
> $ sudo modprobe -r btusb
> $ sudo dmesg | tail -1
> [340608.761313] usbcore: deregistering interface driver btusb
> $ sudo dmesg
> […]
> [340309.272439] usbcore: deregistering interface driver btusb
> [340560.326182] xhci_hcd 0000:00:14.0: hcd_pci_runtime_resume: 0
> [340560.326214] usb usb1: usb auto-resume
> [340560.326258] hub 1-0:1.0: hub_resume
> [340560.326381] usb usb1-port3: status 0107 change 0000
> [340560.326418] usb usb1-port4: status 0107 change 0000
> [340560.326451] usb usb1-port5: status 0507 change 0000
> [340560.326650] hub 1-0:1.0: state 7 ports 12 chg 0000 evt 0000
> [340560.326807] hub 1-0:1.0: state 7 ports 12 chg 0000 evt 0000
> [340560.373988] usb 1-3: usb auto-resume
> [340560.373998] hub 1-0:1.0: state 7 ports 12 chg 0000 evt 0008
> [340560.441936] usb 1-3: Waited 0ms for CONNECT
> [340560.441957] usb 1-3: finish reset-resume
> [340560.570940] usb 1-3: reset full-speed USB device number 2 using xhci_hcd
Those two lines are unexpected. Why does the device need to be reset?
While the btusb module is loaded, does anything show up in
/sys/bus/usb/devices/1-3/quirks?
> > Also, please post the output from "lsusb -v" for the Bluetooth device.
>
> ```
> $ sudo lsusb -d 0cf3:e300 -v
>
> Bus 001 Device 002: ID 0cf3:e300 Qualcomm Atheros Communications QCA61x4
> Bluetooth 4.0
> Device Descriptor:
> bLength 18
> bDescriptorType 1
> bcdUSB 2.01
> bDeviceClass 224 Wireless
> bDeviceSubClass 1 Radio Frequency
> bDeviceProtocol 1 Bluetooth
> bMaxPacketSize0 64
> idVendor 0x0cf3 Qualcomm Atheros Communications
> idProduct 0xe300 QCA61x4 Bluetooth 4.0
> bcdDevice 0.01
> iManufacturer 0
> iProduct 0
> iSerial 0
> bNumConfigurations 1
> Configuration Descriptor:
> bLength 9
> bDescriptorType 2
> wTotalLength 0x00b1
> bNumInterfaces 2
> bConfigurationValue 1
> iConfiguration 0
> bmAttributes 0xe0
> Self Powered
> Remote Wakeup
That's what I was interested in. The device does support remote wakeup.
> PPS: Looking through the commit log/history for `drivers/bluetooth/btusb.c`,
> I found commit 7ecacafc2406 (Bluetooth: btusb: Disable runtime suspend on
> Realtek devices) [1] authored on December 5th, 2019. This is for Realtek
> devices though, and not Qualcomm.
Furthermore the driver has changed considerably since 2019. See
commits 8274db0776d1, 895915226a59, 7bd9fb058d77, and 34ec58b9fd1c.
Alan Stern