Hi, I'm having some trouble getting the USB OTG port to appear as a usb serial port when connected to a PC.
- I.MX6DL custom board based on the SabreSD
- Android kk4.4.3_2.0.0 bsp
- USB OTG works for ADB with CONFIG_USB_G_ANDROID=y in my kernel config.
My understanding is that removing CONFIG_USB_G_ANDROID and setting CONFIG_USB_G_SERIAL=y should enable the serial mode. The device /dev/ttyGS0 appears in my device's file system but no computer sees the device when I plug in the usb otg port. What else should I be doing?
Device Tree Settings
Regulator
reg_usb_otg_vbus: usb_otg_vbus {
compatible = "regulator-fixed";
regulator-name = "usb_otg_vbus";
regulator-min-microvolt = <5000000>;
regulator-max-microvolt = <5000000>;
gpio = <&gpio3 22 0>;
enable-active-high;
};
USB OTG
&usbotg {
vbus-supply = <®_usb_otg_vbus>;
pinctrl-names = "default";
pinctrl-0 = <&pinctrl_usbotg_2>;
disable-over-current;
status = "okay";
};
Hi,
Are you trying to configure the USB OTG port to work as a CDC device?
I just tried it out with L3.14.52 and it worked I just had to modprobe g_serial
Best Regards,
Alejandro
Yeah I'd like it to be a CDC device. I'm trying to get the device to show up as a COM port on my windows PC.
I built the driver statically in the kernel and it appears to be getting loaded on boot:
root@sabresd_6dq:/ # ls -l /sys/module/g_serial
drwxr-xr-x root root 1970-01-01 00:00 parameters
--w------- root root 4096 1970-01-01 00:00 uevent
I think it is something to do with the USB port not being set up correctly. On my old 3.0.35 kernel I used to get messages for each USB port:
ehci_hcd: USB 2.0 'Enhanced' Host Controller (EHCI) Driver
fsl-ehci fsl-ehci.0: Freescale On-Chip EHCI Host Controller
fsl-ehci fsl-ehci.0: new USB bus registered, assigned bus number 1
fsl-ehci fsl-ehci.0: irq 75, io base 0x02184000
fsl-ehci fsl-ehci.0: USB 2.0 started, EHCI 1.00
hub 1-0:1.0: USB hub found
hub 1-0:1.0: 1 port detected
add wake up source irq 72
fsl-ehci fsl-ehci.1: Freescale On-Chip EHCI Host Controller
fsl-ehci fsl-ehci.1: new USB bus registered, assigned bus number 2
fsl-ehci fsl-ehci.1: irq 72, io base 0x02184200
fsl-ehci fsl-ehci.1: USB 2.0 started, EHCI 1.00
hub 2-0:1.0: USB hub found
hub 2-0:1.0: 1 port detected
On the new kernel only one is initialized:
ci_hdrc ci_hdrc.1: doesn't support gadget
ci_hdrc ci_hdrc.1: EHCI Host Controller
ci_hdrc ci_hdrc.1: new USB bus registered, assigned bus number 1
ci_hdrc ci_hdrc.1: USB 2.0 started, EHCI 1.00
usb usb1: New USB device found, idVendor=1d6b, idProduct=0002
usb usb1: New USB device strings: Mfr=3, Product=2, SerialNumber=1
usb usb1: Product: EHCI Host Controller
usb usb1: Manufacturer: Linux 3.10.53-dirty ehci_hcd
usb usb1: SerialNumber: ci_hdrc.1
hub 1-0:1.0: USB hub found
hub 1-0:1.0: 1 port detected
Although it is weird that the Android ADB driver will still work with no mention of the port during the boot log. Any ideas?
Here are the usb related items from the boot log:
usbcore: registered new interface driver asix
usbcore: registered new interface driver ax88179_178a
usbcore: registered new interface driver cdc_ether
usbcore: registered new interface driver net1080
usbcore: registered new interface driver cdc_subset
usbcore: registered new interface driver zaurus
usbcore: registered new interface driver cdc_ncm
ehci_hcd: USB 2.0 'Enhanced' Host Controller (EHCI) Driver
usbcore: registered new interface driver cdc_acm
cdc_acm: USB Abstract Control Model driver for USB modems and ISDN adapters
usbcore: registered new interface driver usb-storage
usbcore: registered new interface driver usbserial
usbcore: registered new interface driver option
usbserial: USB Serial support registered for GSM modem (1-port)
ci_hdrc ci_hdrc.1: doesn't support gadget
ci_hdrc ci_hdrc.1: EHCI Host Controller
ci_hdrc ci_hdrc.1: new USB bus registered, assigned bus number 1
ci_hdrc ci_hdrc.1: USB 2.0 started, EHCI 1.00
usb usb1: New USB device found, idVendor=1d6b, idProduct=0002
usb usb1: New USB device strings: Mfr=3, Product=2, SerialNumber=1
usb usb1: Product: EHCI Host Controller
usb usb1: Manufacturer: Linux 3.10.53-dirty ehci_hcd
usb usb1: SerialNumber: ci_hdrc.1
hub 1-0:1.0: USB hub found
hub 1-0:1.0: 1 port detected
mousedev: PS/2 mouse device common for all mice
usbcore: registered new interface driver xpad
usbcore: registered new interface driver usb_acecad
usbcore: registered new interface driver aiptek
usbcore: registered new interface driver gtco
usbcore: registered new interface driver hanwang
usbcore: registered new interface driver kbtab
usbcore: registered new interface driver wacom
usbcore: registered new interface driver uvcvideo
USB Video Class driver (1.1.1)
...
hidraw: raw HID events driver (C) Jiri Kosina
usbcore: registered new interface driver usbhid
usbhid: USB HID core driver
...
usb_otg_vbus: disabling