USB link to the board

Legato Linux distribution (Yocto project)
1

Hello.
I use wp7502 + legato 20.04

how to understand that USB is connected?
i want to see the USB cable is plugged in or unplugged.

2

how about this?

root@swi-mdm9x28-wp:/sys/bus/platform/drivers# cat /sys/devices/78d9000.usb/power_supply/usb/online
1
root@swi-mdm9x28-wp:/sys/bus/platform/drivers# cat /sys/devices/78d9000.usb/power_supply/usb/online
0
3

When i connect through USB.

root@swi-mdm9x15:~# ls /sys/devices/ -ls
0 drwxr-xr-x 3 root root 0 Jul 6 06:38 breakpoint
0 drwxr-xr-x 6 root root 0 Jan 1 1970 i2c-0
0 drwxr-xr-x 3 root root 0 Jul 6 06:38 msm_def_fab
0 drwxr-xr-x 3 root root 0 Jul 6 06:38 msm_sys_fab
0 drwxr-xr-x 136 root root 0 Jul 6 06:08 platform
0 drwxr-xr-x 3 root root 0 Jul 6 06:38 slimbus
0 drwxr-xr-x 3 root root 0 Jul 6 06:38 software
0 drwxr-xr-x 7 root root 0 Jul 1 10:23 system
0 drwxr-xr-x 3 root root 0 Jul 6 06:38 tracepoint
0 drwxr-xr-x 22 root root 0 Jul 6 06:08 virtual
root@swi-mdm9x15:~#

i not see usb.

5

I am using wp76 …
Can you have a search like

find / -name “power_supply”

6

root@swi-mdm9x15:~# find / -name “power_supply”
/sys/devices/platform/msm_otg/power_supply
/sys/class/power_supply
root@swi-mdm9x15:~#

7

does it work for this path?

/sys/devices/platform/msm_otg/power_supply

8

how to understand that USB is connected?

root@swi-mdm9x15:/sys/devices/platform/msm_otg/power_supply/usb# ls -al
drwxr-xr-x 3 root root 0 Jan 1 1970 .
drwxr-xr-x 3 root root 0 Jan 1 1970 …
-r–r–r-- 1 root root 4096 Jan 1 1970 current_max
lrwxrwxrwx 1 root root 0 Jan 1 1970 device → …/…/…/msm_otg
-r–r–r-- 1 root root 4096 Jan 1 1970 online
drwxr-xr-x 2 root root 0 Jan 1 1970 power
-r–r–r-- 1 root root 4096 Jan 1 1970 present
-r–r–r-- 1 root root 4096 Jan 1 1970 scope
lrwxrwxrwx 1 root root 0 Jan 1 1970 subsystem → …/…/…/…/…/class/power_supply
-r–r–r-- 1 root root 4096 Jan 1 1970 type
-rw-r–r-- 1 root root 4096 Jan 1 1970 uevent

9

alwase “0”
root@swi-mdm9x15:/sys/devices/platform/msm_otg/power_supply/usb# cat online
0

  1. even if I connect via usb
    i see “0”

  2. even if i connect via GSM.
    whith out usb.
    i see “0”

10

I have just made a test with WP8548.

// if USB is connected, /dev/usb_link will be shown in “cat /sys/power/wake_lock”
root@fx30:~# cat /sys/power/wake_lock
/dev/usb_link legato_wakeup_App_wakeup_app

// if USB disconnect, /dev/usb_link will not be shown in “cat /sys/power/wake_lock”
root@fx30:~# cat /sys/power/wake_lock
legato_wakeup_App_wakeup_app

root@fx30:~# cm info
Device:                        WP8548
IMEI:                          359377060004735
IMEISV:                        2F
FSN:                           LL537500110203
Firmware Version:              SWI9X15Y_07.13.07.00 92cfd2c jenkins 2018/08/22 19:18:52
Bootloader Version:            SWI9X15Y_07.13.07.00 92cfd2c jenk[  801.199297] qup_i2c qup_i2c.0: QUP: I2C status flags :0x1363c8, irq:187
ins 2018/08/22 19:18:39
[  801.211750] qup_i2c qup_i2c.0: I2C slave addr:0x3a not connected
MCU Version:                   002.004
PRI Part Number (PN):          9904889
PRI Revision:                  01.11
Carrier PRI Name:              ATT
Carrier PRI Revision:          001.036_000
SKU:                           1102621
Last Reset Cause:              Unknown
Resets Count:                  Expected: 0      Unexpected: 0
root@fx30:~#
1 Like
11

Ok.
path
/sys/power/wake_lock
it work

12

Small question.
On one of my devices, I read the log

root@swi-mdm9x15:/sys/power# cat wake_unlock
/dev/usb_link qcsi qmuxd_port_wl_0 qmuxd_port_wl_1 qmuxd_port_wl_2 qmuxd_port_wl_3 qmuxd_port_wl_4 qmuxd_port_wl_5 qmuxd_port_wl_6 qmuxd_port_wl_7

Why so much qmuxd_port_wl_X ?
for some reason in this file the path /dev/usb_link ?
Is there something wrong?

13

I don’t see this on my wp8548, how to reproduce?

Btw, you should use “cat wake_lock”

1 Like