AM3352: USB on peripheral without PMIC like beagelbone black, what I have to do with the VBUS IRQ

doing it this way does not work too

pin 135 (PIN135): 47401300.usb-phy (GPIO UNCLAIMED) function usb_pins_default group usb_pins_default


root@pxc4:~# dmesg | grep usb
[ 2.541726] device: '47401300.usb-phy': device_add
[ 2.541769] bus: 'platform': add device 47401300.usb-phy
[ 2.542009] device: 'platform:44e10800.pinmux--platform:47401300.usb-phy': device_add
[ 2.542129] platform 47401300.usb-phy: Linked as a sync state only consumer to 44e10800.pinmux
[ 2.542530] device: '47401400.usb': device_add
[ 2.542563] bus: 'platform': add device 47401400.usb
[ 2.542798] device: 'platform:47401300.usb-phy--platform:47401400.usb': device_add
[ 2.542901] platform 47401400.usb: Linked as a sync state only consumer to 47401300.usb-phy
[ 2.543535] device: '47401b00.usb-phy': device_add
[ 2.543570] bus: 'platform': add device 47401b00.usb-phy
[ 2.544811] device: 'platform:47400000.dma-controller--platform:47401400.usb': device_add
[ 2.544917] platform 47401400.usb: Linked as a sync state only consumer to 47400000.dma-controller
[ 3.332068] bus: 'platform': add driver am335x-control-usb
[ 3.332397] bus: 'platform': driver_probe_device: matched device 44e10620.control with driver am335x-control-usb
[ 3.332421] bus: 'platform': really_probe: probing driver am335x-control-usb with device 44e10620.control
[ 3.332459] am335x-control-usb 44e10620.control: no pinctrl handle
[ 3.332559] driver: 'am335x-control-usb': driver_bound: bound to device '44e10620.control'
[ 3.332645] bus: 'platform': really_probe: bound device 44e10620.control to driver am335x-control-usb
[ 3.333040] bus: 'platform': driver_probe_device: matched device 47401300.usb-phy with driver am335x-phy-driver
[ 3.333108] bus: 'platform': really_probe: probing driver am335x-phy-driver with device 47401300.usb-phy
[ 3.333230] am335x-phy-driver 47401300.usb-phy: no init pinctrl state
[ 3.333257] am335x-phy-driver 47401300.usb-phy: no sleep pinctrl state
[ 3.333268] am335x-phy-driver 47401300.usb-phy: no idle pinctrl state
[ 3.334127] am335x-phy-driver 47401300.usb-phy: supply vcc not found, using dummy regulator
[ 3.343199] device: 'regulator:regulator.0--platform:47401300.usb-phy': device_add
[ 3.343342] devices_kset: Moving 47401300.usb-phy to end of list
[ 3.343361] am335x-phy-driver 47401300.usb-phy: Linked as a consumer to regulator.0
[ 3.343388] driver: 'am335x-phy-driver': driver_bound: bound to device '47401300.usb-phy'
[ 3.343410] am335x-phy-driver 47401300.usb-phy: Dropping the link to 44e10800.pinmux
[ 3.343421] device: 'platform:44e10800.pinmux--platform:47401300.usb-phy': device_unregister
[ 3.343601] bus: 'platform': really_probe: bound device 47401300.usb-phy to driver am335x-phy-driver
[ 3.343742] bus: 'platform': driver_probe_device: matched device 47401b00.usb-phy with driver am335x-phy-driver
[ 3.343797] bus: 'platform': really_probe: probing driver am335x-phy-driver with device 47401b00.usb-phy
[ 3.343830] am335x-phy-driver 47401b00.usb-phy: no pinctrl handle
[ 3.344632] am335x-phy-driver 47401b00.usb-phy: supply vcc not found, using dummy regulator
[ 3.353755] device: 'regulator:regulator.0--platform:47401b00.usb-phy': device_add
[ 3.353895] devices_kset: Moving 47401b00.usb-phy to end of list
[ 3.353914] am335x-phy-driver 47401b00.usb-phy: Linked as a consumer to regulator.0
[ 3.353938] driver: 'am335x-phy-driver': driver_bound: bound to device '47401b00.usb-phy'
[ 3.354022] bus: 'platform': really_probe: bound device 47401b00.usb-phy to driver am335x-phy-driver
[ 3.367050] bus: 'platform': add driver musb-hdrc
[ 3.367180] bus: 'platform': add driver musb-dsps
[ 3.367466] bus: 'platform': driver_probe_device: matched device 47401400.usb with driver musb-dsps
[ 3.367533] bus: 'platform': really_probe: probing driver musb-dsps with device 47401400.usb
[ 3.367572] musb-dsps 47401400.usb: no pinctrl handle
[ 3.368105] Registering platform device 'musb-hdrc.0'. Parent at 47401400.usb
[ 3.368126] device: 'musb-hdrc.0': device_add
[ 3.368172] bus: 'platform': add device musb-hdrc.0
[ 3.368529] bus: 'platform': driver_probe_device: matched device musb-hdrc.0 with driver musb-hdrc
[ 3.368551] bus: 'platform': really_probe: probing driver musb-hdrc with device musb-hdrc.0
[ 3.370009] device: 'musb-hdrc.0': device_add
[ 3.370290] driver: 'musb-hdrc': driver_bound: bound to device 'musb-hdrc.0'
[ 3.370374] bus: 'platform': really_probe: bound device musb-hdrc.0 to driver musb-hdrc
[ 3.370441] driver: 'musb-dsps': driver_bound: bound to device '47401400.usb'
[ 3.370463] musb-dsps 47401400.usb: Dropping the link to 47401300.usb-phy
[ 3.370475] device: 'platform:47401300.usb-phy--platform:47401400.usb': device_unregister
[ 3.370601] musb-dsps 47401400.usb: Dropping the link to 47400000.dma-controller
[ 3.370615] device: 'platform:47400000.dma-controller--platform:47401400.usb': device_unregister
[ 3.370738] bus: 'platform': really_probe: bound device 47401400.usb to driver musb-dsps
[ 3.405355] bus: 'usb': add driver usbhid
[ 3.405422] usbcore: registered new interface driver usbhid
[ 3.411278] usbhid: USB HID core driver

at power up at host the gadget is avaliable

Bus 001 Device 020: ID 0525:a4a2 Netchip Technology, Inc. Linux-USB Ethernet/RNDIS Gadget

but after plug event it is lost .. interrupt type / level to add ?

USB0_VBUS is an analog pin with mux mode 0 only.
T19 could not be muxed as GPIO with IRQ !

so what should be added for vbus irq in interruts-extended = <&intc 18 ? ?>

Kernel 4.4 dts didnt has this new "interrupts-extended" gimmick and gadget worked !

Hi Boris,

The VBUS IRQ (as that on BBB) is optional. If you check the AM335x GP EVM schematics and its board dts, there is no VBUS IRQ defined.

I talk not about kernel 4.4.y  without interrupt-extended
I talk about kernel 5.10.y (mainline from kernel.org) with "new" interrupt-extended

Without interrupt-extended for interupt-names "vbus" driver does not work at power up (warning vbus missing)
Without interrupt-extended for interupt-names "mbus" driver does not start (error)
Without interrupt-extended and  interupt-names usb driver does not start (error)

This way RNDIS Gadget works a power up.. but plug event does not work... after unplug you will never see RNDIS again at USB host (Bus 001 Device 020: ID 0525:a4a2 Netchip Technology, Inc. Linux-USB Ethernet/RNDIS Gadget)

If you look at https://elixir.bootlin.com/linux/v5.10.35/source/arch/arm/boot/dts/am33xx.dtsi#L368

mc IRQ is 18 but what IRQ does vbus requires to wake up at plug event.
vbus is analog pin and has Bit 7 in Table 16-116. USB1IRQSTAT1 Register Field Descriptions

how is the VBUS (analog pin) plug event working correctly with interrupt-extended. We have 5V at VBUS if cable is connected and 0 V if not. Was working with 4.4 now 5.10 we have no plug detection

How "vbus" &intc ? is mapped to Bit 7 in Table 16-116. USB1IRQSTAT1 Register Field Descriptions ?

We do not have a PMIC with interrupt-extended = <&intc 18 &tps 0> for "vbus"

Where does the DT screenshot come from? The Beaglebone board DTS or your board? Like I said, the interrupts-extended for VBUS is optional, it is only used in mainline kernel Beaglebone but not other AM335x boards.

Line #844-846 in musb_dsps.c driver checks if VBUS interrupt is defined. The driver does nothing if it is not defined. Also the function name is called dsps_setup_optional_vbus_irq() which suggests the vbus interrupt is opitonal.

https://elixir.bootlin.com/linux/v5.10.35/source/drivers/usb/musb/musb_dsps.c#L844

Boris Schmidt said:

If you look at https://elixir.bootlin.com/linux/v5.10.35/source/arch/arm/boot/dts/am33xx.dtsi#L368

Line 368 in am33xx.dtsi defines the usb register locations, it doesn't talk about interrupts-extended. What do you want to tell with Line 368 here?

Bin Liu said:

Where does the DT screenshot come from?

dts is from our AM3352 module

Bin Liu said:

VBUS is optional, it is only used in mainline kernel Beaglebone but not other AM335x boards.

do you have a link for 5.10 dts where VBUS is not used at &usb0 with dr_mode ="peripheral" ?

I used this as example
elixir.bootlin.com/.../am335x-osd3358-sm-red.dts

Bin Liu said:

The driver does nothing if it is not defined.

Yes - In theory if not defined not Gadget on my real hardware. May you can remove the option on BBB and check if still plug event is working.

Bin Liu said:

Line 368 in am33xx.dtsi defines the usb register locations, it doesn't talk about interrupts-extended. What do you want to tell with Line 368 here?

2 lines below 368 I can see mc and 18 .. both part of interrupts-extends section in dts .. see example

elixir.bootlin.com/.../am335x-osd3358-sm-red.dts

BBB not working RNDIS with default device tree and defconfig, is there a kernel module missing i have to load ?

I use the sato image with modules.dep

root@beaglebone-yocto:/lib/modules/5.10.63-yocto-standard/kernel/drivers/net/usb# lsmod
Module Size Used by
cdc_eem 16384 0
cdc_subset 16384 0
cdc_ncm 28672 0
usb_f_ncm 20480 0
libcomposite 57344 1 usb_f_ncm
configfs 36864 3 usb_f_ncm,libcomposite
rndis_host 16384 0
cdc_ether 16384 2 rndis_host,cdc_ncm
usbnet 36864 5 rndis_host,cdc_eem,cdc_ether,cdc_ncm,cdc_subset
u_ether 24576 1 usb_f_ncm
snd_soc_simple_card 20480 0
snd_soc_simple_card_utils 20480 1 snd_soc_simple_card
snd_soc_davinci_mcasp 28672 2
snd_soc_ti_udma 16384 1 snd_soc_davinci_mcasp
snd_soc_ti_edma 16384 1 snd_soc_davinci_mcasp
snd_soc_ti_sdma 16384 1 snd_soc_davinci_mcasp
snd_soc_hdmi_codec 16384 1
snd_soc_core 200704 7 snd_soc_davinci_mcasp,snd_soc_hdmi_codec,snd_soc_simple_card_utils,snd_soc_ti_sdma,snd_soc_ti_edma,snd_soc_ti_udma,snd_soc_simple_card
snd_pcm_dmaengine 16384 1 snd_soc_core
snd_pcm 102400 4 snd_soc_davinci_mcasp,snd_pcm_dmaengine,snd_soc_hdmi_codec,snd_soc_core
snd_timer 32768 1 snd_pcm
snd 65536 4 snd_soc_hdmi_codec,snd_timer,snd_soc_core,snd_pcm
soundcore 16384 1 snd
root@beaglebone-yocto:/lib/modules/5.10.63-yocto-standard/kernel/drivers/net/usb# uname -a
Linux beaglebone-yocto 5.10.63-yocto-standard #1 PREEMPT Thu Sep 9 02:58:22 UTC 2021 armv7l GNU/Linux

How do you enable the ethernet (RNDIS) gadget on BBB?

I do see u_ether module in 'lsmod', but I expect to see 'g_ether' module as well if the ethernet gadget driver is loaded from command 'modprobe g_ether'.

At 5.10 there is no g_ether.ko and there is no CONFIG for g_ether. only CONFIG_USB_U_ETHER.
Is there a module missing in default omap2plus_defconfig ?

Correct, omap2plus_defconfig has many modules (not limited to USB) not enabled.

To enable USB gadget drivers, including g_ether, you can do it in kernel make menuconfig:

make menuconfig

Device Drivers --->
    USB support --->
        USB Gadget Support --->
            USB Gadget precomposed configurations  --->
               ...

Boris Schmidt said:

yes  an option in dts and can be removed  .. the vbus warning is normal

 &usb0 {
        dr_mode = "peripheral";
-       interrupts-extended = <&intc 18 &tps 0>;
-       interrupt-names = "mc", "vbus";
 };

Yes, this interrupts-extended shouldn't be defined for your board, which doesn't have a PMIC. This VBUS interrupt doesn't exist on your board.