• Jose Ignacio Tornos Martinez's avatar
    net: usb: ax88179_178a: fix failed operations during ax88179_reset · 0739af07
    Jose Ignacio Tornos Martinez authored
    Using generic ASIX Electronics Corp. AX88179 Gigabit Ethernet device,
    the following test cycle has been implemented:
        - power on
        - check logs
        - shutdown
        - after detecting the system shutdown, disconnect power
        - after approximately 60 seconds of sleep, power is restored
    Running some cycles, sometimes error logs like this appear:
        kernel: ax88179_178a 2-9:1.0 (unnamed net_device) (uninitialized): Failed to write reg index 0x0001: -19
        kernel: ax88179_178a 2-9:1.0 (unnamed net_device) (uninitialized): Failed to read reg index 0x0001: -19
        ...
    These failed operation are happening during ax88179_reset execution, so
    the initialization could not be correct.
    
    In order to avoid this, we need to increase the delay after reset and
    clock initial operations. By using these larger values, many cycles
    have been run and no failed operations appear.
    
    It would be better to check some status register to verify when the
    operation has finished, but I do not have found any available information
    (neither in the public datasheets nor in the manufacturer's driver). The
    only available information for the necessary delays is the maufacturer's
    driver (original values) but the proposed values are not enough for the
    tested devices.
    
    Fixes: e2ca90c2 ("ax88179_178a: ASIX AX88179_178A USB 3.0/2.0 to gigabit ethernet adapter driver")
    Reported-by: default avatarHerb Wei <weihao.bj@ieisystem.com>
    Tested-by: default avatarHerb Wei <weihao.bj@ieisystem.com>
    Signed-off-by: default avatarJose Ignacio Tornos Martinez <jtornosm@redhat.com>
    Link: https://lore.kernel.org/r/20231120120642.54334-1-jtornosm@redhat.comSigned-off-by: default avatarJakub Kicinski <kuba@kernel.org>
    0739af07
ax88179_178a.c 48.5 KB